Actual ecological aspects of petrochemical manufactures: educational manual 9786010440968

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AL-FARABI KAZAKH NATIONAL UNIVERSITY

L.R. Sassykova Y.A. Aubakirov Zh.Kh. Tashmukhambetova

ACTUAL ECOLOGICAL ASPECTS OF PETROCHEMICAL MANUFACTURES Educational manual

Almaty «Qazaq University» 2019

UDC 665.6/7 LBC 35.514 S 23 Recommended for publication by the decision of the Academic Council of the Faculty of Chemistry and Chemical Technology and Editorial and Publishing Council of al-Farabi KazNU (Protocol No.4 dated 16.04.2019) Reviewer Doctor of Chemistry, Professor S.M. Tazhibayeva

Sassykova L.R. Actual ecological aspects of petrochemical manufacS 23 tures: educational manual / L.R. Sassykova, Y.A. Aubakirov, Zh.Kh. Tashmukhambetova. – Almaty: Qazaq University, 2019. – 352 p. ISBN 978-601-04-4096-8 The educational manual is constructed in accordance with the requirements of the credit technology program for masters studying in the specialty “Petrochemistry”. The course is designed to study the basic concepts: oil and gas as a source of environmental pollution, influence of emissions of oil and gas on the state of the atmosphere, soil and water resources, ecological characteristics of petrochemical industries, the main directions of protection of nature and human health, ecological monitoring, comparative analysis of various options of the solution of environmental problems of petrochemical processes. The educational manual contains a detailed glossary, questions for selfchecking to each chapter and necessary illustrative material. It is intended for students, masters, bachelors and doctoral students specializing in the field of petrochemistry, chemical technology of organic substances, catalysis, ecology and oil and gas business.

UDC 665.6/7 LBC 35.514 ISBN 978-601-04-4096-8

© Sassykova L.R., Aubakirov Y.A., Tashmukhambetova Zh.Kh., 2019 © Al-Farabi KazNU, 2019

TERMS AND ACRONYMS

ACS – Automated Control System Abs – Absorption Ads – Adsorption AF – Aftertreatment System AIS – Automated Information System APG – Associated Petroleum Gas ASC – Catalyst for the Oxidation of Residual Ammonia ASC – Absorption and Stripping Column AVP – Atmospheric Vacuum Pipe AT – Atmospheric Tube AVT – Atmospheric-Vacuum Tube BСO – Biochemical Consumption of Oxygen BFLH (or WFLH) – Broad (Wide) Fraction of Light Hydrocarbons CCh – Combustion Chamber CСO – Chemical Consumption of Oxygen CDM – The Clean Development Mechanism CED-92 – Conference on Environment and Development (Rio de Janeiro, 1992) CEN – European Committee for Standardization CFR – Code of Federal Regulations CHG – Catalytic Heat Generators CHT – Trap of CH CNPC – China National Petroleum Corporation COPD – Chronic Obstructive Pulmonary Disease 3

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Actual ecological aspects of petrochemical manufactures

°С ChWT DEF Des DOC DPF DRT DSG EIP EDP EG EGR EFNPF EHC EIP EDP EMS EPA EPR GHG GLC GPP GTL FCC FL HAPs HC HC-SCR HPCM ICE IPCC IR Spectroscopy ITLF

– Degree Celsius – Chemical Water Treatment – Diesel Exhaust Fluid (Urea) – Desorption – Diesel Oxidation Catalyst – Diesel Particulate Filter – Decomposition Reaction Tube – Dry Stripped Gas – Eco-Industrial Park – Electrical Desalting Plant – Exhaust Gases – Exhaust Gas Recirculation – Elastic Fine-Pored Polyurethane Foams – Electrically Heating Catalyst – Eco-Industrial Park – Electrical Desalting Plants – Environmental Monitoring Stations – United States Environmental Protection Agency – Electronic Paramagnetic Resonance – Greenhouse Gases – Gas-Liquid Chromatography – A Gas Processing Plant – Gas-to-Liquid Technology – A Fluid Catalytic Cracking – Flammable Liquids – Hazardous Air Pollutants – Hydrocarbons – Hydrocarbons-Selective Catalytic Reduction – High Porous Cellular Materials – Internal Combustion Engines – The Intergovernmental Group of Experts on the UN Climate Change – Infrared Spectroscopy – Installation for Trapping Light Fractions

Terms and acronyms

K KPO LG LOT MAC MEA MHPCM Mi MIC MPC MPE MSC NCOC NEDC NH3-SCR NMOG NSR ORC PAH PCBs PEHP PELP PJI PKOP PM PR PSE PVA PVM REE RFG RP

– Degree Kelvin – Karachaganak Petroleum Operating – Liquefied Gases – Liquid Off Take System – Maximum Allowable Concentrations of Substances in the Air of the Working Area – Monoethanol Amine – Metal High Porous Cellular Materials – Miles – Methylisocyanate – Maximum Permissible Concentration – Maximum Permissible Emission – Metal Supported Catalyst – North Caspian Operating Company – New European Driving Cycle – Selective Catalytic Reduction of NOx with Ammonia – Non-Methane Organic Gases – The NOx Storage and Reduction System – Oxygen Retention Capacity – Polycyclic Aromatic Hydrocarbons – Polychlorinated Biphenyls – Polyethylene of the High Pressure – Polyethylene of the Low Pressure – Projects of Joint Implementation – PetroKazakhstan Oil Products LLP – Particulate Matter – Public Relations – Protection of the Surrounding Environment – Polyvinyl Alcohol – Paint and Varnish Material – Rare Earth Elements – Reformulated Gasoline – Rubber Products

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RSPM RUVW RVW SCA SCR SEM SNG SS Tamb TEL TMCP TOF TPC TPD TPP TPR TPSR TTB TTB TWC UHCs UNEP UNFCCC UV VOCs VT WHO WMB WSSD-2002 XAS λ

– Respirable Suspended Particulate Matter – Rubber Unvulcanized Waste – Rubber Vulcanized Waste – Specific Catalytic Activity – Selective Catalytic Reduction – Scanning Electron Microscopy – Stable Natural Gasoline – State Standard – Ambient Temperature – Tetraethyl Lead – Technical Means of Control of Pollution – Turnover Frequency – Territorial Production Complex – Temperature-Programmed Desorption – Thermal Power Plants – Temperature-Programmed Reduction – Temperature-Programmed Surface Reaction – True Temperatures of Boiling – Temporary Technological Bundle – Three-Way Catalyst – Unburned Hydrocarbons – United Nations Environment Program – United Nations Framework Convention on Climate Change – Ultraviolet – Volatile Organic Compounds – Vacuum Tube – World Health Organization – Water Management Balance – World Summit on Sustainable Development (Johannesburg, 2002) – X-ray Absorption Spectroscopy – Coefficient of Air Excess

INTRODUCTION

A variety of technical systems: mining, chemical, metallurgical complexes, main gas and oil pipelines, represent a real environmental threat. The difference between man-made (technogenic) and natural systems is that their stability and safety decrease as the number of their constituent elements increases (in the case of natural systems, these indicators, on the contrary, raise). The number of manmade accidents in the world is steadily increasing. The consequences of such man-made disasters can affect not only individual regions, but also the globe as a whole, such as, for example, Chernobyl (USSR), Bhopal (India) or Fukushima (Japan). The oil and gas industry is one of the most environmentally hazardous sectors of the economy. It is characterized by its great earthiness, considerable polluting level, and high explosion and fire hazard of industrial facilities. Chemical reagents used in the drilling of wells, extraction and preparation of oil, as well as produced hydrocarbons and their impurities are harmful substances for the plant and animal world, as well as for humans. Oil and gas production is dangerous due to the increased accident rate; the main production processes occur under high pressure. Field equipment and piping systems operate in aggressive environments. 7

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The determining factors of the global oil and gas industry technogenesis are: – scale oil and gas; – the level of their loss in natural and processed form. With modern development methods, about 40–50% of proven oil reserves and 20–40% of natural gas remain unreached and 1–17% of oil, gas and oil products are lost in the processes of extraction, preparation, processing, transportation and use. The loss of oil in the world during its production, processing and use exceeds 45 million tons a year (this is about 2% of the annual production), 22 million tons of them are lost on land, about 7 million tons – in the sea and up to 16 million tons enters the atmosphere due to incomplete combustion of petroleum products during operation of automobile, aircraft and diesel engines. Large complexes of the oil and gas industry and settlements transform almost all components of nature (air, water, soil, flora and fauna, etc.). Every year more than 3 billion tons of solid industrial waste, 500 km3 of sewage, are discharged into the atmosphere, reservoirs and soil in the world. The nomenclature composition of toxic contaminants contains about 800 substances, including mutagens (affect heredity), carcinogens, nervous and blood poisons (functions of the nervous system), allergens, etc. Unregulated, from the point of view of ecology, growth of development of oil, gas and other fuel and energy resources has caused dangerous degradation processes in the lithosphere: landslides, earthquakes, dips, local crustal movement, which negatively affects the distribution of the Earth’s geomagnetic and gravitational fields. The greatest amount of emissions of substances polluting the atmosphere, accounted for torches, especially in emergency situations. Calculations showed that 75% of emissions are emissions of carbon monoxide, CO. In case of incomplete combustion of petroleum gas, it enters the upper atmosphere, where it is oxidized to CO2 and participates in creation of the “greenhouse” effect. Emission of pollutants from oil production facilities creates zones in the field, where surface concentrations 3-10 times exceed the MPC (MAC).

Introduction

At present, the scale of the impact on nature has begun to exceed its regenerative potential. The volume of pollutants in the air, water and soil is constantly growing. The natural environment is irreversibly and dangerously changing. Industrial facilities are sources of emissions of sulfur oxides and nitrogen oxides into the atmosphere and cause an increased risk of the so-called acid rain. The natural environment not only changes itself, but also changes a large variety of biological species (biocenoses). With regard to the oil and gas region, when solving environmental problems, it is necessary to take into account that people must manage the earth, extract and process oil, gas and other minerals in order to survive, and at the current stage of science and technology development there are no such technologies of extraction, transportation and refining, which could be realized without a negative impact on nature. The rational nature management is a compromise between the need for action to ensure economic activities and the corresponding state of the environment (in other words, it is necessary to combine 1 and 2 factors optimally: extract oil and develop fields minimizing negative consequences, restoring disturbed areas as much as possible, avoiding accidental spills of oil). Careful attitude to the objects of nature, the concept of sustainable development of the world community implies consideration of man in unity with all the evolutionary processes taking place on Earth. There is no doubt that creation of favorable conditions for the reduction of environmental pollution is possible only through the combined efforts of the government, legislative bodies, national producers and the entire world community.   Addressing the issues of environmental management in the field of oil and gas processing, legal regulation and state control and examination of the environment at oil and gas enterprises should be one of the priorities of environmental activities of any country. Obviously, the master course students studying in the specialty “Petrochemistry” must know ecological aspects of modern petrochemical productions for search of the correct solution of acute environmental problems

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in their future work activities in the production and in petrochemical laboratories. This manual will allow the master course students with the English language of learning to study the content of the discipline “Actual ecological aspects of petrochemical manufactures” in one semester. The educational manual is constructed in accordance with the requirements of the credit technology program for master course students studying in the specialty “Petrochemistry”. The course is designed to study the basic concepts: oil and gas as a source of environmental pollution, influence of emissions of oil and gas on the state of the atmosphere, soil and water resources, ecological characteristics of petrochemical industries, the main directions of protection of nature and human health, ecological monitoring, comparative analysis of various options of the solution of environmental problems of petrochemical processes. The educational manual is intended for students, masters, bachelors and doctoral students specializing in the field of petrochemistry, chemical technology of organic substances, catalysis, ecology and oil and gas business.

Chapter 1

THE MAIN PROBLEMS OF NATURE MANAGEMENT AND HUMAN IMPACT ON THE BIOSPHERE

1.1. Basic concepts and definitions

At present, mankind is in a period of over-intensive use of environmental resources – the consumption of resources exceeds their restoration, which inevitably leads to the exhaustion of resources. The current ecological state of nature in most countries of the world can be defined as critical. Until recent decades, the culture was mainly developed under the motto “How to do it”. It was believed that the interaction of man with the biosphere is in the plane of conquering nature and is reduced only to a chain of continuous victories over it. I.V.Michurin’s expression is widely known: “We can’t wait for favors from nature, our task is to take them from it”. As a result, the natural conditions on the Earth’s surface began to change noticeably, being clearly traced in the litho-, atmo-, hydro– and biosphere. Their causes are both natural fluctuations of various natural processes under the influence of heliocosmic and tectonic factors, as well as an increase in the human activity. Our reality is that the unity of man with Nature has become illusory, because the natural course of the evolution of the biosphere has disrupted. The man on our planet caused the most significant changes in the biosphere. Anthropogenic impact began to be felt at the global level. So, today for every inhabitant of our planet there are about 400 tons of 11

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annually moved rock and 2 m2 of the newly disturbed earth’s surface. The total mass of mineral raw materials extracted and processed by mankind is 100 gt/year, which is only 10 times less than the mass of organic matter synthesized by the biota (~ 1000 gt/year in live weight), and by the same amount exceeds the volume of matter entering the surface as a result of volcanic activity. As a result, practically everywhere on the globe, traces of human activity are revealed that are manifested in changes in the chemical composition of the atmosphere, land and ocean waters, the regime of surface and groundwater, soil cover, changes in moisture exchange between the Earth’s surface and the atmosphere. The chemicals created by people in increasing quantities are accumulated on the land surface, in the atmosphere and water environment, exerting harmful impact on the terrestrial biota. There is also an increase in the speed of loss of biodiversity. Today F. Engels’s words “We should not live under a delusion of our victories over nature. For each such victory it takes revenge on us, each of such victories has, besides its prime consequences which we expect, absolutely different, unforeseen consequences, which often destroy the value of the first” are very important. The deterioration of the natural environment is explained by the following reasons: • lack of knowledge about ecological systems and the boundaries of their sustainable functioning (ability to withstand the load); • inability to predict changes in the biosphere and their impact on human health; • industry-based and narrowly professional limitations in solving economic and engineering issues, underestimation of measures to prevent degradation and protection of the biosphere; • insignificance of developments or lack of scientific technological schemes, and economic research directed on the development of criteria of development of production for the purpose of maintaining balance of the environment;

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• unpreparedness of production – not all enterprises are equipped with treatment facilities, the available ones often are low-power, etc.; • low qualification of personnel working at treatment plants; • mentality of staff and inertia of thinking. In connection with a sharp and continuous increase in the volume of various emissions from anthropogenic sources, the problem of environmental management and environmental protection at the planetary level has become extremely important. It is also necessary to define a stable and optimal form of interaction between human society and nature, which is an inertial self-regulating mechanism that was previously aimed at preserving, maintaining and increasing the productivity and diversity of the biosphere. D. Meadows developed the basic principles of the concept of sustainable joint development of man and the biosphere: • the rate of consumption of renewable resources should not exceed the rate of their restoration; • the intensity of pollutant emissions should not exceed the capacity of the environment to absorb them; • all resources should be used with maximum efficiency. Therefore, knowledge of the bases of modern environmental management, science about interaction of the person with the biosphere for sustainable development, is necessary for the correct solution of the acute environmental problems realized recently, thus, for the possibility of preservation of mankind. This approach presupposes consideration of a person in the mainstream of the evolutionary process taking place on the Earth, definition of its biosphere function and a scientifically based forecast of future development, based on a retrospective base – the path already traversed by Nature. Thus, favorable opportunities of the evolutionary process and the strategy of coevolution of human society and the biosphere in modern conditions are determined. The public relations concerning protection of the surrounding environment (PSE) are classified depending on the nature of harmful effects.

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1. Public relations (PR) on the chemical impact on nature: the pollution of atmospheric air as a result of pollutant emissions, pollution of water by sewage, soil contamination with chemical fertilizers and pesticides. 2. Public relations (PR) on the deterioration of the PSE state as a result of exposure to harmful physical effects: noise, vibration, electromagnetic fields, radiation pollution. 3. Public relations on the prevention of harmful biological effects in connection with the use of biotechnology, environmental pollution by harmful microorganisms. 1.2. Ecology. Global ecology

In some regions of the world the extent of the negative anthropogenic impact on the PSE has reached such a level that there it is necessary to call these territories as zones of ecological catastrophe. Ecology is a synthetic science which is divided into a set of sections, among which the main three are: • general ecology or bioecology studies the relationship of living systems with the environment and with each other; • geoecology studies the dynamics of geospheres, including the biosphere, their interaction and geophysical conditions of life; • applied ecology studies aspects of engineering and social protection of human environment. The term “ecology” was proposed by E. Haeckel in 1886 and originally designated one of the branches of biology, which studies the interrelationship of the species of living beings and their habitat. The task of ecology as a science is to study human activity in the environment, as well as to study the processes of restoring the environment disturbed by man. Ecology is also a scientific basis for the rational use of natural resources, including minerals. The anthropogenic landscape is the natural landscape transformed by human activity. Usually operating (acting) and thrown objects of subsurface use look depressing.

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For 100 years, the technosphere has increased to 40 million km2, and the biosphere of land decreased by 15%: the area of degraded land reached 2 billion hectares, the forest area fell to 38 million km2. Annually 16 million new cars appear on the roads of the world. New types of weapons of mass destruction have appeared. Moreover, the person has moved technosphere borders far away from the biosphere: space, subsoil, oceans, microcosm. The main tasks of environmental protection are: 1) conservation of natural landscapes and their biocenosis; 2) scientifically based land use; 3) restoration of cleanliness of water and air pools; 4) greening of technological processes related to the use of nature. Global ecology is a complex scientific discipline that studies the biosphere as a whole. The fundamentals of global ecology are formulated by M.I.Budyko, who considers it a central problem of the cycle of substances in the biosphere. The study of this problem is necessary for solving the main task of the global ecology – developing forecasts of possible changes in the biosphere in the future under the influence of human activities. Since this forecast will substantially depend on long-term economic planning and it is associated with large capital investments, it is obvious that it must have a high degree of reliability. Global ecology as a scientific discipline is in the formation stage, its boundaries are not exactly defined. Some scientists consider it to be a division of the general ecology, others are identified with nature protection, human ecology, and others (including M.I. Budyko, I.I. Dedyu) consider it an independent scientific discipline. The human impacts on the natural environment consist of three groups of factors: 1) the population; 2) consumption; 3) technical progress.

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The population is the most important geoecological factor, as it predetermines the needs of society for food, clothing and other services and resources. The population continues to grow and is projected to stabilize at the level of 10 billion people. There is a danger that the needs of the world’s population will exceed the available resources, which can lead to a geoecological crisis and bloody conflicts. In some African countries, the population is already involuntarily regulated due to inter-tribal clashes and civil wars. Consumption is the second most important geoecological factor. The needs of people are growing faster than the population. The difference in consumption levels of different countries is very high. Developed countries are more likely to use Earth’s life support systems, dumping much more pollutants into the water and air than developing countries. Since 1900 the volume of world industrial production has increased almost 25 times. Anthropogenic pressure on the Earth’s ecosphere can be regulated by means of management of population or the magnitude of world consumption, or both at once. Technical progress is the third major geoecological factor. This term is understood as all complex of industries for processing natural resources and use of life support systems of Earth. The mankind annually processes about 100 billion tons of raw materials, using huge power capacities. All these processes are anthropogenic and not characteristic of nature: raw materials are extracted from non-renewable resources; energy is produced by burning fossil fuels not involved in the natural cycles of matter; manufactured products are dumped through rather short time, causing environmental pollution. It is technological progress that causes degradation of the ecosphere. At the same time, technological progress is considered as a basis, thanks to which it is possible to solve the same underlying geoecological problems. Obviously, in the near future humanity needs to ensure the transition to new, less harmful and more controllable technologies.

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Geoecology is a scientific direction that studies the Earth as a system of geospheres in the process of their interaction with the whole aggregate of living matter. If we give a shorter definition, we can say that geoecology is the science of integrating geospheres and society. 1.2.1. Laws of ecology

The basic laws of ecology, which are directly related to the geoecology of subsoil use, include: • limitation of natural resources and a decline in natural and resource potential; • internal dynamic balance of ecological systems; • decrease in energy efficiency of subsoil use: optimality or rationality in geoecology. The law of limitation of natural resources and the decline in the natural resource potential is only valid at the present stage of human activity. At present, the exhaustibility of certain types of mineral resources is an objective reality. Here we mean the limited nature of those natural resources that are involved in the sphere of human activity and cannot be restored in the future. This provision applies primarily to energy carriers, especially oil and natural gas. In fact, the Earth’s energy potential and the amount of solar energy received by the Earth are inexhaustible. The law of reducing the energy efficiency of subsoil use is a consequence of the limited natural resources. Long-developed deposits of minerals have lower production rates. Complicated geographic and mining-geological conditions of occurrence of new deposits of minerals require higher energy and economic costs. The law of optimality and rationality in geoecology exerts impact on the production capacity of an object of subsurface use. The imbalance between the level of development of productive forces and

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a mineral and resource potential of subsurface objects causes social tension. Non-compliance with this law leads to negative social-andecological consequences. Today’s strategy for the development of civilization is mainly based on a technocratic approach, placing man and his technology above everything else. Supporters of this approach believe that the laws of nature cannot and should not interfere with the economic growth and progress of mankind. Unfortunately, this approach is characteristic of most of the people, including high-powered people – business executives and politicians. These people don’t understand that progress of a civilization is limited by an ecological imperative – unconditional dependence of the person on the state of wildlife. Most concisely the laws of ecology were stated by B. Comenar in the following laconic formulas: • everything is connected with everything (reflects the property of generality of ties); • everything has to disappear somewhere (option of conservation laws); • nature knows better (human knowledge of natural processes is limited); • nothing is given by a gift, nothing is free (the use of any resource needs to be compensated). The evolution of the biosphere is due to three groups of factors: – the development of the planet as a cosmic body; – biological evolution of living organisms and human development. V.I. Vernadsky concluded that the biosphere would change to a new state – the noosphere. The noosphere is a new geological envelope of the Earth created by human society on a scientific basis.

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1.2.2. Industrial ecology

Industrial ecology is a scientific basis of rational nature management. The enormous scale of man’s production activity led to great positive changes in the world – creation of a powerful industrial and agricultural potential, wide development of all types of transport, reclamation of large land areas, and creation of artificial climate systems. At the same time the state of the environment has sharply deteriorated. Air pollution, reservoirs and soil solid, liquid and gaseous waste reach the menacing values, there is exhaustion of non-renewable natural resources, first of all, of minerals and fresh water. Further deterioration of the state of the ecosphere can lead to farreaching negative consequences for mankind (an increase in morbidity and infant mortality, a reduction in life expectancy, etc.). Therefore, the protection of nature from pollution has become one of the most important global problems. The modern industrial ecology is an independent science studying influence of industrial activity on the biosphere and its evolution into a technosphere and defining ways of transition of a technosphere, rather painless for a human civilization, to a noosphere. The methodical basis of the course of industrial ecology is the scientific analysis of ecological characteristics of production (technological processes, hardware, raw and auxiliary materials, their possible impact on the environment). On the basis of the detailed analysis, the real impact of production (production complexes) on the biosphere is evaluated, a forecast of the state of the environment is given, and measures to minimize the impact of economic entities on nature are planned. The purposes of industrial ecology are: – solution of problems of rational use of natural resources; – prevention (at the first stage – restriction) of environmental pollution, combination of technogenic and biogeochemical circulations of substances. In other words, industrial ecology is a means for the sustainable functioning of ecological and economic systems.

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The most important tasks facing the industrial ecology are: 1. Control of environmental pollution (and monitoring as the highest form of control). 2. Analysis of the environmental situation (in a broad sense, control includes the inventory of material and energy resources, a qualitative and quantitative assessment of the human impact on the environment and search for the ways to reduce the negative impact of industry on the environment). 3. Identification of polluting industries and sources of pollution. 4. Finding ways to reduce harmful emissions by sources of pollution, taking into account the reduction of material costs for environmental activities. 5. Forecasting the consequences of economic activity. 6. Ecologization of industrial technologies. 7. Purification of air and water. 8. Solution of problems of use or burial of solid industrial and household waste. 9. Ecological-economic examination of technical solutions. Means for solution of the tasks facing industrial ecology include: 1. Modern achievements of science and technology. 2. Economic levers (taxation, stimulation). 3. The nature protection legislation. Complex solution of environmental problems required creation of territorial and industrial complexes and ecological-industrial parks, in which the following tasks are to be solved: – prevention of negative influence of production on the environment; – effective use of raw material and energy resources, including secondary material and energy resources; – accounting of consequences of made decisions; – planning taking into account ecological restrictions; – quality management of the environment; – observation of all technological processes (from processing of raw materials to waste disposal);

Chapter 1. The main problems of nature management and human impact ...

– application of low-waste processes; – recirculation of resources. From the ecological point of view, material flows in nature are closed, while in industry they are open and characterized by small concentrations of useful substances in waste, which hampers their effective use. Currently, the main areas of industrial ecology are: – greening of technologies; – creation of low-waste processes; – cleaning the atmosphere and water resources from harmful impurities; – processing of solid waste (or their burial); – use of economic and legal levers for environmental protection. 1.3. Basic principles of environmental management and low-waste technologies

Waste-free production In the process of development of modern production with its scale and growth rates, the problems of development and deployment of small and waste-free technologies acquire an increasing importance. Their fastest solution in a number of the countries is considered as the strategic direction of rational use of natural resources and environmental protection. The waste-free technology represents such a method of production in which all raw materials and energy are used most efficiently in a complex and in a cycle: raw material resources – production – consumption – secondary resources, and any impacts on the environment do not disturb its normal functioning. This formulation should not be perceived absolutely, i.e. it is not necessary to think that production is possible without waste. It is simply impossible to imagine absolutely waste-free production, it does not exist in nature. However, waste should not break normal functioning of natural systems. In other words, we have to elaborate criteria of undisturbed state of nature.

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The creation of non-waste (waste-free) production refers to a very complex and lengthy process, the intermediate stage of which is a low-waste production. Low-waste production is such production, the results of which under the influence of the environment do not exceed the level allowed by the sanitary hygiene standards, i.e. MAC (maximum allowable concentrations). At the same time, for technical, economic, organizational or other reasons, some of the raw materials and materials can be transferred to waste and sent to long-term storage or disposal. Criteria of wastelessness According to the legislations acting in the countries, the enterprises violating sanitary and environmental standards, do not have right for existence and must be reconstructed or closed, i.e. all modern enterprises must be low-waste and waste-free. The waste-free technology is an ideal model of production which in most cases is implemented now not fully, but only partially. Already there are examples of completely non-waste production. For example, in Russia, for many years, the Volkhov and Pikalev alumina plants process nepheline into alumina, soda, potash and cement using practically non-waste technological schemes. Moreover, the operating costs for the production of alumina, soda, potash and cement, obtained from nepheline raw materials, are 10-15% lower than the costs for production of these products by other industrial methods. 1.3.1. Principles of waste-free technologies

The basic principle is the principle of systemic nature (systemacity). Each individual process or production is considered as an element of a dynamic system – all industrial production in the region (Territorial and Production Complex (TPC)) and as an element of the ecological-economic system in general including not only production of goods and other economic activity of people, but also the environment (populations of live organisms, the atmosphere, the hydrosphere,

Chapter 1. The main problems of nature management and human impact ...

lithosphere, biogeocenoses, landscapes) as well as people and their living environment. Territorial production complex (TPC) is an economic (interdependent) combination of enterprises in one industrial point or in the whole region, where a certain economic effect is achieved due to a successful (planned) selection of enterprises in accordance with the natural and economic conditions of the area, with its transport and economic-geographical position. The principle of systemic nature underlying creation of non-waste production should take into account the existing and growing interconnection and interdependence of production, social and natural processes. Another important principle of creating a non-waste (waste-free) production is the complexity of resource use. This principle requires the maximum use of all components of raw materials and the potential of energy resources. As is known, almost all raw materials are complex, and on average more than a third of their amount is associated elements that can be extracted only by complex processing. Thus, even at the present time almost all silver, bismuth, platinum and platinum group metals as well as more than 20% of the gold are produced simultaneously with the processing of complex ores. The principle of integrated economical use of raw materials in developed countries has been raised to the status of a state task and is clearly formulated in a number of government regulations. One of the general principles of creation of waste-free production is the cyclicity of material flows. It is possible to provide the simplest examples of cyclic material flows: closed water- and gas-reverse cycles. Finally, consecutive use of this principle should lead to formation, at first, in certain regions, and subsequently in all technosphere of consciously organized and adjustable technogenic circulation of substance and related transformations of energy. As effective ways of forming cyclical material flows and rational use of energy, one can point to the combination and cooperation of industries, creation of TPC, as well as the development and produc-

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tion of new types of products, taking into account the requirements for their re-use. It is necessary to refer the requirement of restriction of impact of production on the surrounding natural and social environment, taking into account the systematic and purposeful growth of its volumes and ecological perfection, to not less important principles of creation of waste-free production. This principle first of all is connected with preservation of such natural and social resources as atmospheric air, water, the Earth’s surface, recreational resources, health of the population. The general principle of creation of waste-free production is also the rationality of its organization. The requirement of reasonable use of all components of raw materials, the maximum reduction of energy-, material– and labor– intensity of production and search of new ecologically reasonable raw and energy technologies are defining here. The ultimate goal in this case should be simultaneous optimization of energy, economic and environmental parameters of production. The main way to achieve this goal is to develop new and to improve existing technological processes and industries. One example of this approach to the organization of waste-free production is the utilization of pyrite cinders (pyritic candle ends) – a waste of sulfuric acid production. At present, pyritic cinders are completely used for the production of cement. However, the most valuable components of pyritic cinders – copper, silver, gold, not to mention iron, are not used. However, an economically advantageous technology for processing pyritic cinders (for example, chloride) with extraction of copper, noble metals and subsequent use of iron has been proposed. 1.3.1.1. Directions of creating low– and non-waste (waste-free) production

The main directions of creating low– and non-waste (waste-free) production: – complex use of raw material and energy resources; – improvement of existing and developments of essentially new technological processes and productions and the corresponding equipment;

Chapter 1. The main problems of nature management and human impact ...

– introduction of water – and gas-reverse cycles (on the basis of effective gas-and water treatment methods); – cooperation of production with use of waste of one productions as raw materials for others and creation of waste-free TPC. Requirements for non-waste production: – implementation of production processes with the minimum possible number of technological stages (apparatus), as waste is generated in each of them, and raw materials are lost; – application of continuous processes that allow the most efficient use of raw materials and energy; – increase (up to optimum) of unit capacity of units; – intensification of production processes, their optimization and automation; – creation of energy-technological processes. The combination of energy with technology makes it possible to make fuller use of the energy of chemical transformations, to save energy resources, raw materials and other materials and to increase productivity of aggregates. An example of such production is the large-tonnage production of ammonia by the energy technology scheme.

1.3.1.2. The main directions of development of wasteless and low-waste technology in selected industries

At the current level of development of science and technology, it is practically impossible to do without losses. As the technology of selective separation and interconversion of various substances improves, the losses will constantly decrease. Industrial production without uselessly accumulated material losses and waste already exists in the whole industries, however, its share is still small. The mankind is obliged to deal with the problem of waste-free and low-waste production because at the increasing rates of accumulation of waste the population can be filled up with dumps of industrial and household wastes and be left without drinking water,

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rather clean air and fertile lands. Fuel and industrial complexes of the world can extend further and turn the globe into the territory lowadapted for life. Modern technology is sufficiently developed to stop the growth of waste in a number of industries and productions. And in this process, the state should assume the role of the leader and, in a planned manner, develop and implement a comprehensive state program for introducing non-waste production and processing the accumulated waste. The main directions of development of wasteless and low-waste technology in the industries: 1. Power Engineering It is necessary: – to provide greater use of new methods of fuel combustion, for example, such as fluidized bed combustion, which helps to reduce the content of pollutants in waste gases; – to implement developments for purification of gas emissions from sulfur and nitrogen oxides; – to achieve the operation of dust-cleaning equipment with the highest possible efficiency, with the efficient use of the resulting ash as raw material in the production of building materials and in other industries. 2. Mining It is necessary: – to introduce the developed technologies for the complete utilization of waste, both in open and underground mining of minerals; – to make more extensive use of geotechnological methods for the development of mineral deposits, while striving to extract only target components to the earth’s surface; – to use waste-free methods of enrichment and processing of natural resources in the place of their production; – to use hydrometallurgical methods of ore processing more widely. 3. Metallurgy It is necessary: – to process gaseous, liquid and solid waste of production, reduce emissions and dumpings of harmful substances with flue gases and sewage;

Chapter 1. The main problems of nature management and human impact ...

– to provide widespread use of large-tonnage dump solid waste of mining and concentrating production as building materials for laying mines, pavements, wall blocks etc., instead of specially mined resources; – to process in full all blast-furnace and ferro-alloy slags, as well as to significantly increase in scale of processing steel smelting slags and non-ferrous metallurgy slags; – to provide sharp reduction of fresh water costs and a decrease in wastewater through further development and introduction of anhydrous technological processes and drainless water supply systems; – to increase the efficiency of existing and newly created processes for capturing by-products from waste gases and sewage; – to provide wide introduction of dry methods of gas purification from dust for all types of metallurgical productions and the search for improved methods for cleaning off-gases; – to utilize weak (less than 3.5% sulfur) sulfur-containing gases of variable composition by introducing an efficient method at the nonferrous metallurgy enterprises – oxidation of sulfur dioxide in the nonstationary regime of double contacting; – to accelerate introduction of resource-saving autogenous processes, including melting in a liquid bath, at the enterprises of nonferrous metallurgy, which will allow them not only to intensify the process of processing raw materials, and reduce energy consumption, but also to significantly improve the air pool in the area of operation of enterprises due to a sharp reduction in the volume of waste gases and to obtain highly concentrated sulfur-containing gases used in the production of sulfuric acid and elemental sulfur; – to develop and widely introduce the highly effective cleaning equipment and also devices supervisory of different parameters of impurity of the environment at metallurgical enterprises; to introduce fast development and deployment of new progressive low-waste and waste-free processes, meaning direct reduction and cokeless processes of steel production, powder metallurgy, autogenous processes in nonferrous metallurgy and other perspective technological processes directed on reduction of emissions to the environment;

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– to expand application of microelectronics, ACS (automated control system) by technological processes in metallurgy in order to save energy and materials, as well as control the formation of waste and reduce it. 4. Chemical and petroleum industry It is necessary to use in technological processes: – oxidation and reduction using oxygen, nitrogen and air; – electrochemical methods, membrane technology of separation of gas and liquid mixtures; – biotechnology, including production of biogas from residues of organic products; – methods of radiation, ultraviolet, electropulse and plasma intensification of chemical reactions. 5. Mechanical engineering In the field of galvanic production: – it is necessary to direct research activity and developments to water purification; – to proceed to the closed processes of recirculation of water and extraction of metals of sewage; – in the field of processing of metals to wider introduce obtaining details from press powders. 6. Paper industry In the first place, it is necessary: – to implement developments to reduce consumption of fresh water per unit, giving preference to creation of closed and drainage industrial water supply systems; – to maximize the use of extractive compounds: contained in wood raw materials to produce the desired products; – to improve bleaching of cellulose with oxygen and ozone; – to improve processing of logging waste by biotechnological methods into targeted products; – to ensure creation of capacities for processing of paper waste, including waste paper. The economic development of the TPC provides for creation of an efficient structure for the production of basic types of products, in-

Chapter 1. The main problems of nature management and human impact ...

frastructure for ensuring production of these products, protecting the environment and rational use of natural resources. When allocating the productive forces, it is necessary: – to provide maximum conservation of natural conditions in protected areas; – to introduce low-waste and non-waste or clean processes and industries that consume a minimal amount of raw materials and materials; – to economically use available land and, first of all, fertile; – to redistribute natural resources and industrial raw materials in order to create conditions for preservation of favorable natural environment; – to restrict or even stop individual production in some areas (resort or tourist zones, reserves, zones of intensive residential development, etc.), and in some cases, on the contrary, create new ones (for example, enterprises producing building materials where the majority of waste can be used). Of great importance in the protection of the environment are the development and construction in settlements of enterprises processing industrial and municipal waste, planting trees, creating sanitary protection zones and conducting some other sanitary and hygienic measures. Special attention should be paid to the enterprises producing construction materials as they can use a large amount of waste that gives a chance not only to improve economic indicators of the enterprises and the region in general, but also to considerably reduce harmful effects of the industry on the environment. Processing of large-tonnage waste of chemical metallurgical, power generation and other productions into valuable construction materials and products allows us to free the scarce land grounds, which are taken away under dumps, it is very essential to reduce environmental pollution and to raise the degree of safety of the national economy of the country with construction materials at the minimum costs of production. Use of waste promotes an increase in profitability of the enterprises making waste and the enterprises processing it, cuts costs for exploration works and economy of natural raw materials in

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general i.e. increases the efficiency of capital investments in the national economy. Eco-Industrial Park (EIP) is an association of producers of goods and services wishing to improve the economic and environmental situation through joint management of natural resources (energy, water and materials) and the environment. Working together, manufacturers hope to get a collective effect more than they would have individually. The goal of Eco-Industrial Park is to improve the economic status of participating producers and to reduce environmental pollution. This approach includes planning (or re-planning) of the park infrastructure, prevention of environmental pollution, increasing the efficiency of the use of raw materials and energy resources and the partnership between the producers of goods and services. Through mutual cooperation these enterprises become an industrial ecosystem. Questions for self-checking: 1. Justify the reasons for the deterioration of the natural environment. 2. List the statements of I.V. Michurin and F. Engels on the relationship of man to nature. 3. What are the conclusions of D. Meadows? 4. List and explain the laws of geoecology. 5. What are the main objectives of environmental protection of nature? 6. What is “global ecology”? Who and when first proposed this term? 7. What is the ecological imperative? 8. What is the eco-centric approach? 9. List the laws of B. Comenar. 10. What is an anthropogenic landscape? Tell us about the conditions of its formation. 11. What are the characteristics of public relations regarding the protection of the natural environment? 12. What is the dynamics of the use of secondary raw materials in developed countries? 13. What is the scale of the negative impact of industrial production on the environment? 14. What does the industrial ecology study? 15. What are the goals and objectives of industrial ecology? 16. What is “wasteless (waste-free) technology”? 17. What are the principles of waste-free technologies? 18. What are the requirements for non-waste production? 19. Give examples of the implementation of non-waste technology in various industries. 20. What is TPC? 21. What is an eco-industrial park?

Chapter 2

GENERAL CONCEPTS OF OIL AND OIL REFINING

2.1. General information and some facts from history

Oil is a mineral that is an oily liquid. It is a combustible substance, often black in color, although the colors of oil vary from region to region. It can be brown, and cherry, green, yellow, and even transparent. From the chemical point of view, oil is a complex mixture of hydrocarbons mixed with various compounds, for example, sulfur, nitrogen and others. Its odor can also be different, since it depends on the presence of aromatic hydrocarbons and sulfur compounds in its composition. The hydrocarbons that make up oil are chemical compounds consisting of carbon (C) and hydrogen (H) atoms. In general, the hydrocarbon formula is CxHy. The simplest hydrocarbon, methane, has one carbon atom and four hydrogen atoms, its formula is CH4. Methane is a light hydrocarbon, always present in oil. Depending on the quantitative ratio of the various hydrocarbons that make up oil, its properties also differ. Oil can be transparent and fluid like water. And it can be black and so viscous and slow-moving that it does not flow out of the vessel, even if it is turned over. Oil (and its accompanying hydrocarbon gas) lies at depths from several tens of meters to 5-6 kilometers. At that, only gas is found at depths of 6 km and below, and at the depths of 1 km and above only oil is found. Most productive reservoirs are at a depth between 1 and 31

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6 km, where oil and gas are found in various combinations. Oil is found in mountain reservoir rocks. The formation of oil is a very long process. It passes in several stages and takes, according to some estimates, 50-350 million years. According to the theory of the organic origin of petroleum (biogenic theory), oil was formed from the remains of microorganisms that lived millions of years ago in extensive water basins (mainly in shallow water). Dying off, these microorganisms formed at the bottom layers with the high content of organic substance. Layers, gradually plunging more and more deeply (this process takes millions of years), were affected by the increasing pressure of the top layers and temperature increase. As a result of the biochemical processes proceeding without oxygen access, organic substance was transformed into hydrocarbons. Some part of the formed hydrocarbons was in the gaseous state (the lightest), the other was in the liquid (heavier) and still other was in the solid form. Respectively, mobile mixture of hydrocarbons in gaseous and liquid state under the influence of pressure gradually moved through permeable rocks towards smaller pressure (as a rule, upward). The movement continued until a thickness of impenetrable layers was met on their way and further movement was impossible. It is the so-called trap formed by reservoir-layer and the impenetrable layer-cover covering it. In this trap a mixture of hydrocarbons gradually accumulated, forming what is called the oil field. Thus, the oil field actually is not the birthplace of oil, but the place of its congestion. Oil is known to people since the most ancient times. The term “oil” comes from the Persian language through the Turkish word “neft”. There are the data that 6,500 years ago the people living in the territory of modern Iraq added oil to the construction and cementing material at construction of houses to protect the dwellings from moisture penetration. Ancient Egyptians collected oil from the water surface and used it in construction and for lighting. Oil was also used for sealing boats and as a component of the mummifying substance. At the time of ancient Babylon in the Middle East quite intensive business on the base of this “black gold” was done. Some

Chapter 2. General concepts of oil and oil refining

cities already then literally grew on trade in oil. One of the Seven Wonders of the World, the well-known Hanging gardens of Seramida (according to other version – Hanging gardens of Babylon), also used oil as a sealing material. Not everywhere oil was collected only from the surface. In China more than 2000 years ago small boreholes were drilled using bamboo trunks with a metal tip. Initially wells were intended for extraction of salty water from which salt was extracted. But when drilling deeply, oil and gas were also extracted from wells. It is unknown whether oil found application in ancient China, it is known only that the gas was ignited for evaporation of water and salt extraction. Approximately 750 years ago, the famous traveler Marco Polo in his description of his travels to the East mentioned the use of oil by the inhabitants of the Absheron peninsula as a remedy for skin diseases and fuel for lighting. The first mentions of oil in the territory of Russia belong to the 15th century. Oil was collected from the water surface on the river Ukhta. Just like other peoples, the local population used it as a medicine and for economic needs. Russia is the birthplace of industrial oil refining (about Kazakhstan’ oil and gas fields see Chapter 9). Fedor Pryadanov built the first oil refinery on the basis of Ukhta oil in 1745, giving annually up to a thousand poods of “pure transparent oil”. It represented a broad fraction in the amount of up to 60% of crude oil, similar to kerosene. This liquid was used for medical purposes and as lamp oil. Up to now original drawings of the plant of pioneers of oil processing – brothers Vasily, Gerasim and Makar Dubinins, serfs of the countess Panina, have remained (Fig. 1). The plant was constructed in 1823 in Mozdok and successfully used the Grozny oil. The distillation cube of periodic action with a capacity of 40 buckets (about 500 liters) was a basis of the plant. The yield of kerosene was about 40 % of oil. At those primitive plants from oil only lighting kerosene was separated, and lighter fractions – gasoline and heavy – fuel oil was burnt in “black oil” pits as not finding applications.

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Figure 1. Oil refining cube of Dubinin brothers

The first installations abroad were built in England in 1848, and in the USA in 1860. The first units for primary oil refining were made in the form of periodic batch cubes. The target product of these units was the lighting kerosene. The rest of the products were burned. But already in the 80s of the XIX century the cubes were replaced by batteries of cubes, which ensure the continuity of distillation of oil. They were created by famous Russian engineers A.F. Inchik, V.G. Shukhov and N.I. Elin (Fig. 2). A great contribution to the technology of oil refining was made by the eminent Russian scientist D.I. Mendeleyev. According to its scheme, oil refining cubes were combined into a so-called cubic battery and were connected to each other by overflow pipes, through which oil was gradually poured from one boiler to the next. Each boiler was heated by a separate firebox and was equipped with a refrigerator and a receiver for collecting the fraction. Crude oil was fed to the top section of the bottom battery. Gasoline was distilled off in the first section, kerosene in the next section, and then fuel oil (Fig. 3, 4). “There is nothing Russian to learn from Americans”, wrote D.I. Mendeleyev on his return from the United States, where he traveled to get acquainted with the methods of oil production and refining. Indeed, D.I. Mendeleyev’ method of refining oil in the United States began to be used only in 1899. D.I. Mendeleyev stressed the importance of oil as a valuable raw material for the synthesis of various products and said at a conference

Chapter 2. General concepts of oil and oil refining

of Russian chemists in Moscow in 1887: “Burning oil and gas in furnaces is tantamount to burning banknotes in the furnace”.

Figure 2. Oil refining device of continuous action designed by V.G. Shukhov

Figure 3. The oil refining device of continuous action designed by D.I. Mendeleyev

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Figure 4. Cubic battery for continuous distillation of oil according to D.I. Mendeleyev at one of the Nobel Brothers plants in Baku

According to some sources, the world’s first oil well was drilled in 1847 near the city of Baku on the shore of the Caspian Sea. Soon after, numerous oil wells were drilled in Baku, which was a part of the Russian Empire at that time, and this city was called the Black City. Nevertheless, the year 1864 is considered to be the birth of the Russian oil industry. In the autumn of 1864 in the Kuban region, a transition was made from a manual method of drilling oil wells to a mechanical shock-rod with the use of the steam engine as a drive of the drilling rig. With the invention of nozzles for liquid fuel in 1876, fuel oil was found to be used as fuel for boiler units. Another application of fuel oil was found by D.I. Mendeleyev, who suggested using it as a lubricant instead of vegetable and animal fats. The starting date of commercial world oil production, according to the majority of sources, is considered to be August 27, 1859. It is the day when in the USA the first oil well was drilled by “colonel” Edwin Drake and an inflow of oil with the fixed yield was obtained.

Chapter 2. General concepts of oil and oil refining

This well of 21.2 meters in depth had been drilled by Drake in the city of Taytusvil, State of Pennsylvania where drilling of water wells was often followed by oil presence. Although oil has been known since ancient times, it has found rather limited use. The modern history of oil begins in 1853, when the Polish chemist Ignaty Lukasevich invented a safe and easy-to-use kerosene lamp. He, according to some sources, discovered a way to extract kerosene from oil on an industrial scale and founded in 1856 an oil refinery in the vicinity of the Polish city Ulaszowice. In 1846 the Canadian chemist Abraham Gössner invented a method of obtaining kerosene from coal. But oil allowed to obtain cheaper kerosene and in much bigger amounts. The growing demand for the kerosene used for lighting generated a high demand for initial material. The second half of the 19th century was called in history of oil industry as the “kerosene” period. Virtually, the first two places in the entire period from the beginning of the oil industry (since 1859) were almost always taken by the USA and Russia. Until 1913, when the world’s first thermal cracking unit was launched in the United States, only the primary distillation of oil was produced in oil refineries, whose products – gas, gasoline, kerosene, diesel fuel, fuel oil and others – were the marketable products. From that time the epoch of secondary processes in oil refining started. The raw material for the newly introduced unit was the gas oil fractions of the primary distillation of oil, cracking of which was carried out at elevated temperatures and pressures. In connection with ever increasing requirements to the quality of motor fuels, primarily to the detonation properties, in the 20-30s of the XX century there was a rapid development of secondary processes of oil refining. Industrial processes of catalytic cracking of middle distillates, alkylation of alkenes, polymerization of lower alkenes were mastered. In the USSR, the first refineries were built after the Civil War in the late 1920s.

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The rapid growth of oil refining was observed all over the world after the 2nd World War. The main milestones in the history of the world oil processing are briefly given in table1. Table 1

Brief history of world oil refining No Years 1 2 1 1862 2

1870

Name of the process 3 Atmospheric distillation Vacuum distillation

3

1913

Thermal cracking

4 5 6 7 8

1916 1930 1932 1932 1933

Desulfuration Thermal reforming Hydrogenation Coking Solvent extraction

9 1935 10 1935 11 1937

Solvent dewaxing Catalytic polymerization Catalytic cracking

12 1939 13 1940

Visbreaking Alkylation

14 1940

Isomerization

15 1942 16 1950 17 1952 18 1954

The process aim 4 To produce kerosene

By-products 5 Naphtha, tar

To produce lubricants (original) and cracking feedstocks To i������������������������ ncrease gasoline�������� producing To reduce sulfur and odor To increase octane number Sulfur removal Base gasoline production To improve lubricant viscosity index To improve pour point To improve gasoline yield and octane number To obtain gasoline with higher octane number To reduce viscosity To increase octane number and yield of gasoline

Asphalt, residual coker feedstocks Residual, bunker fuel Sulfur Residual Sulfur Coke Aromatics

To produce alkylation raw materials Fluid catalytic To increase octane number cracking and yield of gasoline Deasphalting To increase cracking feedstock Catalytic reforming To convert low-quality naphtha Hydrodesulfurization Sulfur removal

Waxes Petrochemical raw materials Petrochemical raw materials Distillate, tar High-octane aviation gasoline Naphtha Petrochemical raw materials Asphalt Aromatics Sulfur

Chapter 2. General concepts of oil and oil refining 1 2 19 1956 20 1957 21 1960 22 1974 23 1975

3 Desulfuration, demercaptanization Catalytic isomerization Hydrocracking Catalytic dewaxing Residual hydrocracking

4 Removal of mercaptans

5 Disulfides

To produce molecules with high octane number To improve quality and to reduce sulfur content To improve pour point To increase gasoline yield from residual

Alkylation feedstocks Alkylation feedstocks Waxes Heavy residuals

2.1.1. Organization of countries – exporters of oil (OPEC)

In September, 1960 at a conference in Baghdad the international organization of the countries – exporters of petroleum (OPEC) was created. Initially OPEC consisted of five countries – Iran, Iraq, Kuwait, Saudi Arabia and Venezuela, and then the other six – Qatar (1961), Indonesia and Libya (1962), UAE (1967), Algeria (1969) and Nigeria (1971) joined it. The supreme body of OPEC is the Conference consisting of the delegations representing the member states, headed by ministers of oil mining industry or power engineering. Meetings of the Conference are held two times a year, in the OPEC headquarters located in Vienna (Austria). General Secretary (from August 01, 2016) is Mohammed Barkindo. The purpose of OPEC is carrying out the coordinated policy for establishment of the accepted oil prices for producers, ensuring efficient, regular and profitable supply with oil of consuming countries; ensuring fair receipt of income from investments by investors in the oil industry; environmental protection; cooperation with the countries – not members of OPEC for realization of initiatives of stabilization of the world oil market. For the members of the cartel, high prices are the vital necessity, as the export of oil is not only a significant share of their budget revenues, but also the gross national product of these countries. All OPEC countries are deeply dependent on the income of their oil industry. Perhaps the only country that represents the excep-

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tion is Indonesia, which receives substantial revenues from tourism, forests, gas and other raw materials. For other OPEC countries, the level of dependence on oil exports varies from the lowest – 48% in the case of the United Arab Emirates – to 97% in Nigeria. The countries members of OPEC control about 2/3 of world reserves of oil. About 35% of the global production or a half of the world oil export fall to their share. Now the proved reserves of oil of the OPEC countries make 1199.71 billion barrels. Today OPEC consists of 14 countries: Algeria, Angola, Venezuela, Gabon, Iran, Iraq, Congo, Kuwait, Libya, United Arab Emirates, Nigeria, Saudi Arabia, Equatorial Guinea and Ecuador. In 1992, Ecuador left OPEC (entered in 1973) due to disagreements over the allocation of quotas for oil production. In November 2007, the membership was restored. In January 1995, Gabon left OPEC (entered in 1975). The reason was too high a membership fee (in OPEC, all member countries pay the same amount to the budget, which is set at the conference annually and averages $ 2 million). Gabon once again became a full member of the cartel on July 1, 2016. On January 1, 2009, Indonesia left the organization (entered in 1962) because it lost the status of an oil exporter (its production volume dropped sharply, and the country was faced with the task of increasing supplies to the domestic market). Indonesia returned to OPEC on January 1, 2016. However, already on November 30, 2016, the membership was again suspended, since it could not provide the necessary volumes of oil production. Qatar, which joined OPEC in 1961, left the organization on January 1, 2019 in connection with the decision to concentrate on increasing natural gas production (from 77 million to 110 million tons annually). Currently, Qatar provides almost 30% of the world gas production, while in OPEC it is not a leading player. The country accounts for just over 2% of OPEC’s proven oil reserves and about 2% of its daily production. Production of liquefied natural gas is planned to increase from 77 to 110 million tons per year. Earlier, Qatar announced plans to launch four new LNG production lines until 2024. Already, it is the largest exporter of this type of raw material. In Doha it was underlined

Chapter 2. General concepts of oil and oil refining

that the country would continue to fulfill all international agreements, and the decision to withdraw was purely economic in nature and not due to disagreements with the other members of the organization. 2.2. Oil refining

Today oil, as well as natural gas, is the main and almost an unalternative source of energy, and its reserves are irretrievable. Thus, only 10% of extracted crude oil are subjected to further processing, and the remaining 90% – are incinerated. The reserves of petroleum and gas amount to several billion tons. In the list of countries with the largest reserves of oil are: Saudi Arabia, Iran, Iraq, Kuwait, Venezuela, the United Arab Emirates, Russia, Libya, Kazakhstan, Nigeria, the United States, Canada, Qatar, China, Angola. Consumption of petroleum in the world will grow according to forecasts to about 5.335 million tons by 2030. More than 80.0% of the growth in oil consumption from the total are the share of the developing countries of Asia and the Middle East, in which higher economic growth rates are expected. The main consumer of oil is the transport sector (80%). The greatest growth in oil consumption is expected in the developing countries in Asia: in China and India. By the increased volume of consumption of fluid hydrocarbons China wins the first place in the world. China is the leading country of the world in use of oil in the chemical and petrochemical industry. Today China is the second largest importer of petroleum from the USA. As the USA, China has huge production of its own oil. After China the second place in terms of increasing oil consumption occupies the Middle East, especially Saudi Arabia, Iran and Turkey. In Latin America: Brazil (more than half), Argentina (agricultural sector), and Venezuela (more than 60% of its oil will be spent on transport). Regardless of the forecast, the oil is to be the dominant source of energy. The main importers of oil in the medium term will be the countries of South-East Asia, Central and Eastern Europe.

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If we look at geography of oil and gas fields, it is easy to notice that many of them are located in the sea. It is considered that potential marine resources of hydrocarbon raw materials make more than half of the world. Today extraction of the offshore oil reaches about one third of its total extraction. The main part of initial explored reserves and the modern extraction of hydrocarbon raw materials on the shelf belong to five regions: The Persian Gulf, the lake Maracaibo (belongs to Venezuela and Colombia), the Gulf of Mexico, the Caspian and North Sea. Oil industry is the branch of the heavy industry which includes exploration of oil and gas fields, oil and petroleum gas production, processing, transportation and sale of petroleum and gas. The purpose of petroleum refining (oil processing) is production of oil products, first of all, various fuels (automobile, aviation, boiler etc.) and raw materials for the subsequent chemical processing. Oil products (Fig. 5) are the mixtures of hydrocarbons and some of their derivants; individual chemical compounds obtained at petroleum refining and used as fuels, lubricants, insulant environments, solvents, road surfaces, petrochemical raw materials. A considerable proportion of oil products is the mixes of individual hydrocarbon components containing various additives improving properties of oil products and increasing stability of their production characteristics. Fuel (gaseous and liquid) is one of the main oil product groups. Hydrocarbon oils (petroleum oils) is the second by volume and by value group of oil products. Oil technical asphalts – bitumen (road, structural asphalts) is the third by volume production group of marketable oil products, widely used in the national economy. So-called solid hydrocarbons belong to oil products: paraffins, ceresines, vaselines, petrolatum, ozokerite, etc. Marketable oil products are also various solvents, refinery coke, soot, emulsion breakers (demulsifiers) and so forth. Oil products obtained by separation of fractions of a pyrolysis of petroleum (benzene, toluene, a xylol, naphthalene, green oil, etc.), are applied generally as petrochemical feedstocks. As chemical raw materials also the oil-refinery gases are used.

Chapter 2. General concepts of oil and oil refining

Figure 5. The oil products Questions for self-checking: 1. Tell the history of use of oil and gas by mankind since the most ancient times. 2. Describe the history of the global oil industry until now. 3. What are the world’s recoverable reserves of oil and natural gas? 4. What countries are in the list of countries with the largest reserves of oil and gas? 5. Tell about the OPEC countries. 6. Tell about the history of OPEC. 7. What were the main purposes for OPEC creation? 8. How many countries were included into OPEC at the beginning of creation of this organization? 9. Explain the role of oil in the fuel and energy balance. 10. What is oil industry? What are the oil products? 11. Tell about oil and gas as valuable raw materials for petrochemistry.

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Chapter 3

PHYSICOCHEMICAL PROPERTIES OF OIL AND GAS

3.1. Physical properties of oil

Physical and chemical properties of oil in reservoir conditions considerably differ from the properties of the degassed crude. The differences are due to the high reservoir pressures, temperatures and dissolved gas content. 1. Density ρ is a ratio of mass to volume, measured by hydrometer, the device for determining the depth of immersion density of the liquid of the float. Oil density ranges from 730 to 980 kg /m3 (density less than 800 kg/m3 has gas condensates. Usually density of the separated oil ranges within 820-950 kg /m3. By the value of density, the oil is conventionally divided into three groups: – light (820-860); – medium (860-900); – heavy with a density of 900-950 kg/m3. Density determines the quality of oil. At the initial stage of development of the oil industry the main indicator of the quality of oil was density. Light oils are the most valuable. The light oil contains more gasoline and kerosene fractions, and comparatively little sulfur and tar. From the same oils it is possible to produce high quality grease oils. Heavy petroleums, by contrast, are characterized by a high content of resin-asphaltene substances of het44

Chapter 3. Physicochemical properties of oil and gas

eroatomic compounds and therefore are not very suitable for production of oils and give a relatively small yield of fuel fractions. 2. Viscosity is the property of liquid or gas showing resistance to movement of one of its particles with respect to others. It depends in most interactions between liquid molecules. Viscosity is changed over a wide range and depends on chemical and fractional composition of oil and resinousness (gummosity, content of asphaltene-resinous substances in it). The more cyclic (aromatic or naphthenic) compounds contained in the oil molecule, the higher its viscosity. The viscosity of oil is significantly reduced with an increase in its light fractions. According to G.F.Trebin, viscosity of oil at reservoir conditions of different fields varies from hundreds of mPa⋅s to tenths of mPa⋅s (about 25% of deposits), from 1.0 to 7.0 mPa (about 50% of deposits) and from 5.0 to 30.0 mPa⋅s (about 25% of deposits). The viscosity affects the rheological properties of oils (their flowability). 3. Fluorescence is the glow of the substance directly by initiating or continuing in no more than 10-77 s after stopping of stimulation. If after cessation of excitation the substance continues to glow for a while (more than 10-77 s), we speak about phosphorescence. Oil and majority of oil products, except for the lightest distillates, fluoresce themselves, and in the majority of organic solvents at their irradiation, even by daylight. Colour of luminescence in ultraviolet rays of highgravity oils is intensively blue, of heavy resinous – the colours are yellow-brown and brown. 4. Oil and oil products are dielectrics, i.e. they do not conduct electric current. 5. The molecular weight of oil is arithmetically averaged molecular weight of its fractions. The molecular weight of the crude oil varies from 240 to 290. With a significant content of resinous substances it exceeds the specified maximum. 6. The amount of gas dissolved in oil depends on the composition of oil and gas as well as on the temperature and pressure at which dissolution occurs. According to Ya.D. Savina and A.S. Velikovsky, the number of atoms of carbon in a molecule of liquid hydrocarbon (at otherwise equal conditions) decreases in the series: methane hydrocarbons ˃ naphthenic hydrocarbons ˃ aromatic hydrocarbons.

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Actual ecological aspects of petrochemical manufactures

A.S.Velikovsky noted that the more petroleum gasoline contains, the richer it is in methane hydrocarbons and the poorer in aromatic, especially polycyclic, hydrocarbons, the more gas it can dissolve. In gas-oil deposits, about 1,000 m3 of gas can be contained per 1.0 m3 of petroleum. For gas condensate deposits on 1.0 m3 of condensate can be contained about 900-1,100 m3 of gas (a gas condensate factor). In the earth subsoil at increase of pressure a part of gas is liquefied, and at further increase in pressure the formed liquid can pass into a gas phase again. The phenomena of transition of gas mixture at increase of pressure through a liquid phase into vapour and at pressure drop into liquid again are called retrograde. Retrograde condensation is observed on many oil fields. Deposits in which petroleum is in a vaporous state are called condensate. 7. Photocolorimetry is one of the research methods of changing properties of oil on a deposit. The method is based on the solution’s ability to absorb light. The degree of absorption of light flux (colorimetric properties of oil) depends on the content of asphalt-resinous substances. Along with the change in the content of petroleum, its viscosity, density and other properties are changed, and therefore one can see the dependence of the change of other parameters on the change of colorimetric properties of oil. 8. Crystallization temperature of hydrocarbons increase in the process of increase of their molecular mass and boiling point. The highest temperature of crystallization is observed for hydrocarbons with the symmetric structure of molecules. Highly branched alkanes, as well as alkanes containing multiple alkyl substituents (monocyclic cycloalkanes, arenes and naphthalene homologs) are not crystallized and turn into an amorphous state. Usually crystallization of paraffin and ceresines occurs at higher temperatures, than those at which oil product loses mobility. For the operational purposes it is important to know not only the pour point but also the temperature when the wax crystallization starts. 9. Crystallization of paraffin is followed by oil product opacification. Emergence of “clouds” of fine crystals in the mass of the

Chapter 3. Physicochemical properties of oil and gas

oil product is the moment of opacification. Temperature recorded at the same time is called the cloud point (opacity temperature). It is a production characteristic. It is defined visually by comparison of the cooled oil product to the transparent standard. 10. Temperature of solidification (freezing) is a temperature at which the fraction cooled in a test tube does not change the level at the test tube inclination to 45 °C. Physical properties and petroleum composition within the same layer not always remain constant. Change of properties of petroleum depends generally on the layer depth (depth of bedding of the reservoir). For the separation of hydrocarbon gases their sorption by different adsorbents is used. As the sorbent carbon, silica gel and others are often used. The chromatographic methods of separate determination of hydrocarbons are based on the ability of these adsorbents adsorb hydrocarbons. Questions for self-checking: 1. Describe oil classification according to density. 2. What oils are the most valuable? 3. What is viscosity? 4. What oil properties does the viscosity affect? 5. Explain the terms fluorescence and phosphorescence. 6. Do gases and petroleum conduct electric current? 7. What determines the amount of dissolved gas in oil? 8. Tell about A.S. Velikovsky’s conclusions about hydrocarbon gas solubility. 9. What is the phenomenon “retrograde”? 10. Tell about photocolorimetry. 11. Explain the property of oil – crystallization. 12. What is opacification? 13. Describe the term “temperature of solidification (freezing)”. 14. What method for the separation of hydrocarbon gases is used? 15. What sorbents for the separation of hydrocarbon gases are used?

3.2. The elemental composition of oil

Oil is a combustible oily liquid, mainly, dark color, represents a mixture of various hydrocarbons. The color of oil varies from light brown to dark brown and black. The elemental composition of the

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oil and natural gas is quite simple. In their structure, mainly, biogenic elements – the main substances in the structure of any substance of organic origin, are present. Such elements include carbon (C), hydrogen (H), oxygen (O), sulfur (S) and nitrogen (N). Thus, the basic elements of petroleum composition are: – carbon (83.5-87.0%) and hydrogen (11.5-14.0%). Besides, oil contains: – sulfur – in amount from 0.1 to 1.0-2.0% (its contents can sometimes reach 5.0-7.0%, in many oils, sulfur does not practically present); – nitrogen – in amount from 0.001 to 1.0 (sometimes to 1.7%); – oxygen (does not occur in the pure form but in various compounds) – in an amount from 0.01 to 1% or more but less than 3.6%. Compared with the elementary composition of organic matter, the oxygen role in oils and natural gas is negligible. From other elements oil contains iron, magnesium, aluminum, copper, tin, sodium, cobalt, chrome, germanium, vanadium, nickel, hydrargyrum, gold and others. However, their contents are less than 1.0%. Oil, by its elementary composition, is close to other combustible minerals which organic origin is not in doubt. The following groups of hydrocarbons are encountered in oil: – methane (paraffin) СnН2n+2; – naphthenic – СnН2ni; – aromatic – СnH2n-6. Predominant hydrocarbons of the methane series. The important place in petroleum composition is occupied by microminerals, and among them metals. By now more than 30 metal elements and 20 nonmetal elements were revealed in oils, the average concentration of microminerals in petroleums decreases in such sequence: Cl, V, Fe, Ca, Ni, Na, K, Mg, Si, Al, I, Br, Hg, Zn, P, Mo, Cr, Sr, Rb, Co, Mn, Ba, Se, As, Ga, Cs, Ge, Ag, Sb, U, Hf, Eu, Re, La, Sc, Pb, Au, Be, Ti, Sn. The greatest attention should be paid to transitional and alkaline earth metals capable to form complexes: V, Ni, Fe, Zn, Sa, Hg, Cr, Cu, Mn.

Chapter 3. Physicochemical properties of oil and gas

The organic components (mainly polynuclear arene and heteroatomic compounds) can act as complexing agents, extractants in which the donor-acceptor bond is localized on their collective n-systems, and also on the heteroatoms N, S, O. The source of the metals in oils, presumably, can be oil-forming organisms, as well as adsorbed or trapped (in the process of migration from the rocks or water), microelements, and there is a straightforward correlation between the content of certain elements. For example, concentration of the V is associated with the content of sulfur, and Ni – with the content of nitrogen. And in general – it is associated with the content of atom ligand. A part of metals in oils is in the form of salts of organic acids of the R-COOM type or the chelate complexes in which the atom of the metal is placed in the coordination center of a porphyrinic cycle or in the condensed aromatic fragments (Fig. 6). The main mass of metal is in the form of complex multidentate complexes, many of which can enter into an ion exchange with the metals which are present in M+ solutions A– or on the surface of the rocks (MA) of X which are immediately adjoining petroleum. Such elements as V, Ni, Mo, Co, Cr, Sb, Ga, Ge, La and others, are concentrated mainly in the asphalt-resinous fractions in which they are present in the form of metal-porphyrins (V, Ni), salts of metals (Mo, Ge et al.), or complexes with hetero systems of asphaltene polyaromatic structures (Co, Ni, Cr, and others.) and other compounds. Group of metals Pb, Zn, Cu, Hg, Se, As is found in high-boiling oil fractions and prevails in the oil bitumen components.

Figure 6. Metals in the structure of oils placed in the coordination center of a porphyrinic cycle or in the condensed aromatic fragments

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Actual ecological aspects of petrochemical manufactures

These metals form organometallic compounds, such as mercury Hg alkyl (Alk)2, alkyl and aryl lead Pb (Alk)4, or complexes with various organic ligands (Fig. 7). The compounds of the non-porphyrin nature can be divided into two major groups: 1) containing ligands of pseudo porphyrin structure (they are characterized by higher aromaticity, lack of conjugation in the macrocycle, highly resistant to demetallization under the influence of acids); 2) vanadium complexes with tetradentate ligands having mixed donor atoms (they are characterized by a complete lack of aromaticity and easy acidic demetalization).

Figure 7. The scheme of the structure of vanadyl porphyrin complexes containing the most common metal of oil – vanadium

The content of an element, such as vanadium, in petroleum products can be compared with its content in the ores. In the oil tars and fuel oils, for example, the vanadium concentration can reach tenths of a percent. The petroleums enriched with metals are usually oils of those fields in which the average content of both V, and Ni reaches

Chapter 3. Physicochemical properties of oil and gas

10-2 %. The richest with vanadium is the petroleum of Venezuela where the concentration of this metal can reach 1.38∙10-2 % (in the desalinated oil). All metal elements (except for Na, Sa, Al, V, Ni) are uniformly distributed in higher-boiling and residual fractions of oil. The prevailing part of vanadium (to 98%) in petroleum crude oil is concentrated in the heavy petroleum residues obtained after distillation. During the extraction and adsorption-extraction separation the largest concentrations of vanadium and nickel are typical for the enriched fractions of aromatic fragments extracted with benzene-containing solvents. There is a certain regularity in the ratio of nickel and vanadium in crude oils; this ratio is fairly constant and is considered as one of the common indicators of oil. The tendency of decrease in the values of the ratio of V/Ni from ancient to young oils and the boundary value of this index (between paleozoic and mesocainozoic petroleums) equal to unit, has global distribution. Vanadium and nickel complexes found in all acidic, basic and neutral fractions are characterized by a wide molecular weight distribution. The models of non-porphyrin compounds are very conjectural; they are based on EPR, UV and mass spectroscopy, chromatographic methods, and on spectroscopic studies. Close attention to the vanadium-containing compounds of oil is not so much due to the problem of vanadium extraction from the alternative (petroleum) raw materials, but also due to the fact that the corrosive properties of the metal and its compounds damage the refinery equipment and oil combustion plants, put petroleum refining catalysts out of action, reduce endurance of turbojet, diesel, gas-turbine and boiler installations. Formed in this process inorganic vanadium compounds (sodium vanadate) are one of the main reasons for intensive ash drift and high-corrosion of surfaces. Vanadium-organic compounds reduce the performance of the finished oil products, and the vanadyl porphyrins present in oils are also a major oil emulsion stabilizers, complicating their destruction. Porphyrins are the typical examples of native oil complex compounds. Due to the possibility to obtain significant amounts of elements from petroleum feedstock, demetallization processes are becoming in-

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creasingly important. At present, almost no such methods of refining, which would be seen as a process of transformation of only organic components of petroleum, exist. Therefore, one of the important directions of modern petrochemical industry has become the new, environmentally clean, technology of extraction of metallic components from the oil. The refining methods proposed for industrial use, among others, should take into account such an important factor as the prevention of waste and emissions into the atmosphere of the resulting highly toxic V2O5 oxide. To capture vanadium from ash the electrostatic method is offered. This method of cleaning is used in power stations, but it can also be useful in the petrochemical industry. If the ash contains large amounts of metals (0.5-1.0% of Ni and 1.9-3.4% of V), suche metals can be leached efficiently under mild acidic reducing conditions. Today, leaching of heavy oil residues is the most common and effective method of extracting oil microelements concentrated in these residues. As extractants, it is possible to use not only the alkali, but also acids and some oxides as additives. It is hardly expedient to extract iron from oils, which is distributed on all intervals of boiling points of fractions, and its content is many orders lower than the content in ores. This can be attributed to aluminum, copper, cobalt, manganese and other metals. Rare-earth metals in oils may have deserved attention by the purpose of their selection. Toxic elements, like mercury, should be identified mainly in order to avoid getting into the atmosphere in the refining processes. Large quantities of chlorine are present (about 10-2%) in the oils, fluorine is not detected in them. Iodine is available in low-boiling and bromine – in the high-boiling fractions. In the countries with a highly developed petrochemical industry, strict laws against oil waste, toxic metals are adopted. However, there are still a number of unresolved issues: – still unknown contamination of previous years, when no appropriate actions are accepted; – further development of the petrochemical industry is associated with the introduction of new metal-containing catalysts, reforming, cracking, etc., and some of them with toxic properties;

Chapter 3. Physicochemical properties of oil and gas

– the synergy phenomena of two or more different heavy metals with respect to the environment is unclear. 3.3. Hydrocarbon composition of oil. Oil fractions. The group composition

A.A.Petrov, the author of a series of well-known monographs devoted to chemical composition of oils, claimed that in oils about one thousand of individual hydrocarbons of composition С1-С40 are identified. The oil systems differ in variety of the components capable to be in a molecular or dispersible state depending on external conditions. In terms of substances oil consists mainly of hydrocarbons and hetero compounds. Among the latter, the focus should be on the resin asphaltene substances (RAS), which can be regarded as a concentrate of compounds most prone to intermolecular interactions. Oil generally contains the following hydrocarbon classes. Alkanes or paraffin hydrocarbons – saturated hydrocarbons (HC) with the general formula CnH2n+2. Its oil content is from 2.0 to 30-70%. There is the normal structure of alkanes (n-alkanes – pentane and its homologs), branched chain (isoalkanes -. Iso-pentane, etc.) and the structure of isoprenoid (isoprene – pristane, phytane et al.). Oil contains gaseous alkanes from C1 to C4 (in the form of dissolved gas), liquid alkanes C5-C16, which form the bulk of the liquid fraction of oil and solid alkanes composition of C17-C53 and more, which are included in heavy petroleum fractions and are known as solid paraffins. Solid alkanes are present in all crude oils, but usually in small amounts – from a few tenths up to 5% (wt.), in rare cases – up to 7-12% (wt.). For example, in the Tomsk region, Chkalovsky oil field contains up to 18% of hard paraffin. Oils may also contain various isomers of alkanes: mono-, di-, and more– substituted. Among them mono-substituted isomers with one branching predominate. Methyl-substituted alkanes in descending order are arranged sequentially: 2-methyl-substituted alkanes > 3-methyl-substituted alkanes > 4-methyl-substituted alkanes.

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Thus, in various proportions alkanes are part of all natural mixtures and petroleum products, and their physical state in the mixture – in the form of molecular solution or dispersion system – is determined by the composition, the individual physical properties of the components and thermobaric conditions. Cycloalkanes or naphthenic hydrocarbons are saturated alicyclic HC. These include monocyclic having the general formula CnH2n, bicyclic – CnH2n-2, tricyclic – CnH2n-4, tetracyclic – CnH2n-6. According to the total contents, cycloalkanes in many oils prevail over other classes of HC: their content ranges from 25 to 75% (wt.). They are present in all oil fractions. Typically, their content increases in the process of weighting of fractions. The total content of naphthenic hydrocarbons in oil increases with increasing of its molecular weight. The only exception is the oil fraction in which the content of cycloalkanes decreases with increasing number of aromatic hydrocarbons. From the monocyclic HC, five– and six-term series of naphthenic HC are mainly present in oil. Arenes or aromatic hydrocarbons can be compounds in whose molecules cyclic hydrocarbons having π-conjugate systems are present. Their oil content ranges from 10-15 up to 50% (wt.). They are representatives of monocyclic benzene and its homologues (toluene, o-, m-, p-xylene, etc.), Bicyclic: naphthalene and its homologues, tricyclic: phenanthrene, anthracene, and their homologues, tetracyclic: pyrene and its homologues and others. The common regularity is an increase in the contents of arenes with an increase in the boiling point. Monoarenes of oils are presented by alkylbenzenes. The most important representatives of high oil alkylbenzenes are hydrocarbons containing benzene ring up to three methyl and one long linear substituent, α-metilalkyl or isoprenoid structure. The large alkyl substituents in the molecules of alkylbenzenes may contain more than 30 carbon atoms. The main place among oil arenes of a bicyclic structure (diarenes) belongs to naphthalene derivatives which can make up to 95% of the sum of diarenes and contain up to 8 saturated rings in a molecule, and

Chapter 3. Physicochemical properties of oil and gas

the minor – a derivative of diphenyl and diphenylalkanes. All individual alkylnaphthalenes C11, C12 and C13 isomers of many-C15 are identified in oils. The content of biphenyls in oils is an order lower than the content of naphthalene. From nafteno-diarenes in oils acenaphthene, fluorene and a number of its homologues containing methyl substituents in the positions 1-4 are found. Triarenes are presented in oils by derivants of phenanthrene and anthracene (with a sharp dominance of the first) which may contain up to 4-5 saturated cycles in molecules. Oil tetraarenes include series of chrysene, pyrene, 2,3-benzo and 3,4-phenanthrene and triphenylene. Heteroorganic compounds (sulfur-, oxygen- and nitrogen-containing) of different structure and molecular weight are present in various proportions in distillate and residual oil fractions. Sulfur-containing compounds are the most representative group of heteroatomic components of gas condensate and oil systems. The total sulfur content in the oil and gas systems varies widely: from a few hundredths of percent to 6-8% (wt.) or more. The content of sulfur compounds in the oils is up to 40% (wt.), and higher, in some cases oil is composed almost entirely of them. Oxygen-containing compounds make from 0.1-1.0 to 3.6% (wt.) in oil systems. With increasing boiling point of distillate fractions their contents increase, and the main part of oxygen is concentrated in the asphaltene resin. As a part of oils and distillates, oxygen-containing compounds make about 20% and more. Substances of acidic and neutral character are traditionally distinguished from them. Carboxylic acids and phenols belong to acidic components. Neutral oxygen-containing compounds are presented by ketones, acid amides and anhydrides, esters, furan derivatives, alcohols and lactones. Nitrogen-containing compounds are contained in petroleum (by the data for 500 oils) in the range of 0.02-0.40% (wt.), although in some cases may reach even 0.8-1.5%. All nitrogen compounds of oil are usually functional derivatives of arenes, therefore they have a similar molecular weight distribution. However, unlike the arenes nitrogen containing compounds are concentrated in high-boiling oil fractions.

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Pyridine derivatives are more often found in crude oil and straightrun distillates. With increasing boiling temperature of the fraction, generally increases the content of nitrogen compounds, thus changing their structure: in light and middle fractions predominate pyridines, in heavier – their polyaromatic derivants prevail, and in the products of thermal processing at elevated temperatures there are more anilines. In the light fractions nitrogenous bases dominate, and heavy fractions, usually – neutral nitrogen compounds. The fraction is the share of petroleum which is boiling away in a particular interval of temperatures. Fractional composition is an important indicator of the quality of petroleum. It is determined in laboratory distillation, in the course of which at gradually increasing temperature parts – fractions differing from each other by the range of boiling are distillated from petroleum. Fractional composition of petroleum shows the content of various fractions, which are boiling away in particular temperature intervals, and the content of substances in them. Oils boil over in a very wide temperature range, generally from 28 to 520-540 °C. Fractional composition of oil is determined by the standard method (SS 2177-82) by the results of the laboratory tests on separation of compounds by the boiling point using the method of fractionation (distillation) of crude oil, distillate, or a mixture of compounds in AVP (atmospheric vacuum pipe) plants. The beginning of the boiling temperature of the faction is considered the fall of the first drops of condensed vapour. The end of boiling fraction is considered the temperature at which evaporation of fraction is terminated. In table 2 the list of the main fractions of oil is presented. Group petroleum composition (fractions) is a quantitative ratio of separate groups of hydrocarbons, heteroatomic compounds in it. The analytical methods developed in the sixties of the 20th century allowed us to change the idea of composition and structure of oil hydrocarbons and to specify the principles and methods of oil analyses. In oils, the large number (over 500) of relict hydrocarbons (hemofossiliya) was revealed. By the results of analyses it was offered to di-

Chapter 3. Physicochemical properties of oil and gas

vide all petroleum hydrocarbons into two basic groups conditionally: the transformed hydrocarbons and the relict hydrocarbons. The relict hydrocarbons: these are normal and isoprenoid alkanes, cyclic isoprenoids – steranes, triterpans and others. In turn, the relict hydrocarbons of oils can be divided into isoprenoid hydrocarbons and non-isoprenoid type. The group of relict isoprenoid hydrocarbons in crude oils consists of a much larger number of different compounds than the group of non-isoprenoid hydrocarbons. The relict hydrocarbons of non-isoprenoid type are generally presented by aliphatic compounds, and hydrocarbons of isoprenoid type – by aliphatic and alicyclic hydrocarbons with the number of cycles in a molecule from one to five. The most important property of relict petroleum hydrocarbons is their homology. Homologous series of 2-methylalkanes, 3-methylalkanes, 4-methyl-alkanes, 1-methyl-2-alkylcyclo-hexanes, 1-methyl-3-alkylcyclohexa­nes were defined. A.A. Petrov by GLC and mass spectrometry investigated about 400 oils from almost all major oil and gas basins of the former Soviet Union. All the investigated oils (table 3) were assigned to the categories A and B. Table 2

The oil fractions The boiling points of fractions, °C

The oil fractions

28-180

wide gasoline fraction

140-200

white spirit

180-320

wide kerosene fraction

150-240

lamp oil (lighting kerosene)

180-280

jet fuel

140-340

diesel fuel (summer)

180-360

diesel fuel (winter)

350-500

wide oil fraction

380-540

vacuum gas oil

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The category A is petroleum if on chromatograms of fraction 200-430°C in analytical amounts n-alkanes peaks are shown. On chromatograms of fractions of oils of category B peaks of n-alkanes are absent. Depending on the relative content of normal and isoprenoid hydrocarbons in the oils of the category A and the presence or absence of isoprenoid hydrocarbons in petroleum of category B, the oils of each category are divided into two subtypes: A1, A2, B1, B2. The group composition of oils of different chemical types (fraction 200-430 °C) Type А1 А2 B1 B2

Total 15-60 (25-50) 10-30 (15-25) 4-10 (6-10) 5-30 (10-25)

Alkanes n-structure 5-25 (8-12) 0.5-5 (1-3) 0.5

branched 0.05-6.0 (0.5-3) 1.0-6.0 (1.5-3) 0.5-6.0 (0.2-3)

Table 3

Cycloalkanes

Arenes

15-45 (20-40) 20-60 (35-55) 20-70 (50-65) 20-70 (35-55)

10-70 (20-40) 15-70 (20-40) 25-80 (25-50) 20-80 (20-45)

Figures in parentheses refer to the predominantly occurring hydrocarbons. The oils of the A1 type correspond to the oils of the paraffin and naphthene-paraffinic basis. The maintenance of the sum of alkanes in fraction 200– 430 °C is equal to 15 – 60%. It usually has a high content of n-alkanes (5-25% per studied fraction). The total content of cycloalkanes in the A1-type oils is slightly less than that of alkanes. Cycloalkanes are mainly represented by mono– and bicyclic compounds, and monocycloalkane content is often equal to or greater than the content of bicyclanes. Type A1 of oil is the most widespread in nature and occurs in all oil and gas basins of the former Soviet Union in the sediments of any geological age, usually at a depth of over 1,500 m (Romashkino, Samotlor).

Chapter 3. Physicochemical properties of oil and gas

The oils of type A2 by group composition correspond to naphthene-paraffin and paraffin-naphthenic. The alkanes content as compared to oil type A1 is slightly lower and reaches values of 25-40%. The alkanes content is in the range of 0.5-5% and that of isoprenoids is 1.6%. A distinctive feature of most oils of type A2 is the predominance of branched alkanes over normal. The total content of cycloalkanes reaches 60%. Among cycloalkanes prevail mono – and bicyclic hydrocarbons, although the maintenance of tricyclanes is slightly higher, than in A1 oils. The oils of the South Caspian (Surakhani, Oil Rocks, Duvanny sea), Western Siberia (Soleninskoye), Caspian (Koshkar, Kalamkas, Kara-Tube) belong to the A2 type. Oils of type B2 are the oils of paraffin-naphthenic and particularly naphthenic bases. Among the saturated hydrocarbons cycloalkanes are predominant (60-75%), and among them – the mono-, bi- and tricyclic hydrocarbons. Alkane hydrocarbons (5-30%) are mainly presented by branched structures. A distinctive feature of oils of type B2 is the absence of peaks on the chromatograms of monomethyl alkanes. Oils of type B2 are more common than type A2, and are distributed mainly in the Cenozoic sediments at depths of 1000-1500 m. Oils of type B2 are the oils from the North Caucasus (the Old-Grozny, Trinity-Anastasievskoy), Georgia (Norio, Mirzaani) and others. Petroleums of the B1 type by the group composition are petroleums of the naphthenic or naphthene-aromatic basis. They contain few light distillates. A characteristic feature of this type of oils is total absence of normal and isoprenoid alkanes and low content of other branched alkanes (4-10%). Among cycloalkanes, prevalence of bicyclic hydrocarbons over monocyclic is observed. The oils of the B1 type are more widespread in Cainozoic deposits of many oil and gas bearing basins at depths of 500-1000 m – oils of the Southern Caspian Sea and the North of Western Siberia – the Mud Hill, Surakhana, Balakhana, Russian, etc. Questions for self-checking: 1. What classes of hydrocarbons are in petroleum? 2. Tell about A.A.Petrov’ research.

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Actual ecological aspects of petrochemical manufactures 3. Give the examples of alkanes in the composition of oils. 4. List the examples of di, tri- and tetra-arenes in oils. 5. What heteroorganic compounds of different structure and molecular weight can be in oils? 6. List the sulfur-containing compounds of oils. 7. Describe the oxygen-containing compounds of oils. 8. Tell about nitrogen-containing compounds of oils. 9. What is a group petroleum composition (fractions)? 10. Give two basic groups of all petroleum hydrocarbons. 11. Tell about the relict hydrocarbons. 12. Describe hydrocarbons of isoprenoid type. 13. Tell about hydrocarbons of non-isoprenoid type. 14. What is the most important property of relict petroleum hydrocarbons? 15. What types of oil were described by A.A.Petrov? 16. What features do the oils of A type have? 17. Tell about the oils of the B type.

3.4. Analysis of oil and oil fractions

There are the following types of analyses of oil and oil fractions: elemental, individual, group, structural-group. Data on the element composition of oil and oil products are necessary for calculation of processes of burning, gasification, and coking. Data of the elemental and structural-group composition of narrow fractions and heavy oil residues can significantly extend understanding of the structure of substances in these fractions, and build a model of their “middle” molecule. Elemental analysis of carbon and hydrogen is based on nonresidual combustion of the organic mass of oil in a stream of oxygen to carbon dioxide and water. They were collected and according to their number the content of these elements is calculated. Burning should be complete (forming CO is oxidized to CO2), and the combustion products must be free of sulfur oxides, halogens and other contaminants. Determination of sulfur is carried out by various methods. For light oil products, the lamp method, or the combustion in a quartz tube is used. For medium and heavy oils, the method of washout of condensate at burning of the sample in calorimetric bomb is used.

Chapter 3. Physicochemical properties of oil and gas

The content of nitrogen is determined by Dumas or Kyeldal’s method. In Kyeldal’s method the oil product is oxidized with the concentrated sulfuric acid. Dumas’s method is based on oil product oxidation by a solid oxidizer – copper (II) oxide – in the carbon dioxide current. The percentage of oxygen is determined most often by the difference between 100 and the total content of all other elements as a percentage. This method is inaccurate: errors of definition of all other elements affect its results. The gravimetric method of pyrolysis of oil products in the inert gas current in the presence of platinized graphite and copper oxide is a direct method of dedermination of the amount of oxygen. The content of O2 can be determined by the mass of released CO2. Determination of group composition Even narrow fractions of oil are complex mixtures of hydrocarbons and heteroatomic compounds. Narrow gasoline and kerosene fractions can even be divided into individual hydrocarbons by gasliquid chromatography. Despite the relative speed of the chromatographic analysis, interpretation and calculation of chromatograms of complex mixtures is very time-consuming. For industrial purposes, there is often no need for such a detailed analysis. It is enough to know the total hydrocarbon content of the classes. Methods for determination of the composition of petroleum products by the content of one or other classes of hydrocarbons can be divided into the following types: chemical, physico-chemical, combined and physical. Chemical methods include interaction of the reagent with hydrocarbons of a certain class (arenes or alkenes) by the existence of which, we can judge about the change of volume or quantity of the formed reaction products. Such methods include nitration and sulfonation. Physico-chemical methods: extraction and adsorption (extraction of arenes with sulfur dioxide, dimethyl sulfate, aniline, these hydrocarbons on silica gel).

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The combined methods are the most accurate, widely distributed and are based on the combined use of any of the two methods: remove arenes by chemical or physico-chemical methods and measure physical properties of the oil (density, refractive index, change of the critical temperature of dissolution in other liquids, and others) before and after removal of the arenes. Physical methods are primarily based on the determination of optical properties. Mass spectrometry was first used for the analysis of low-boiling oil fractions in 1940. It is possible to use this method for the analysis of medium and heavy oil fractions. The mass spectrometer contains the following main blocks: – a source of ions in which molecules of the analyzed substance are ionized; – the analyzer where the division of ions proceeds; the system of input of substance into the ion source; – the system of registration of mass spectrum; the pumping system providing necessary vacuum. The masses of the fragment ions formed during the dissociative ionization can be predicted on the basis of the molecular structure. On the contrary, by the mass of the formed fragmental ions it is possible to judge what structural elements were a part of the studied compounds. The influence of the structural features of the molecules of the analyzed compounds on the directions of molecular ion decomposition can be characterized by ion intensity curves for a number of carbon atoms. In mass spectra of complex mixes it is possible to determine the groups ions (for alkanes – peaks of ions of СпH2п+1, for alkylbenzene – СпH2п-7), which are defined by some structural fragments of molecules. In gasoiline fractions the content of n-alkanes and isoalkanes, the cyclopentane and cyclohexane hydrocarbons, alkylbenzenes is determined by the method of mass spectrometry. In kerosene-gasoil and oil fractions alkanes, mono-, di- and tricyclanes, alkyl benzenes, the indanes and the tetralins, alkyl naphthalenes, diphenyls and acenaphthenes, acenaphthylene and fluorenes, phenanthrenes and anthracenes, benzothiophenes are determined. Us-

Chapter 3. Physicochemical properties of oil and gas

ing mass spectrometry it is possible to estimate the degree of condensation of rings, the average length of the substituent, the average degree of substitution. The method of chromato-mass spectrometry is a combination of a gas or liquid chromatography, allowing to divide the analyzed fraction into components with mass spectrometric identification. Ultraviolet and infrared spectroscopy are widely used in the analysis of oils. Absorption of energy in the ultra-violet area is connected with changes in the energy of external electrons. In organic compounds such absorption is associated with transition of valent σ- and π- electrons from the connecting orbitals to the corresponding disintegrating orbitals, and also with transitions of electrons of not divided couples of heteroatoms (n-electrons) of type n → π* and σ → n*. Due to the high sensitivity, the UV spectroscopy is used to define traces of arenes in the non-aromatic products. In order to determine the group composition of complex mixtures usually characteristic, i.e., intense bands practically retaining the general form and intensity independent of the structure of the remainder of the molecule are used. The position of the characteristic bands is changed within a small range – up to half-width. IR spectra can be used to determine the type of oils. Measure of the content of arenes is an area (S1) of band ν = 1,610 cm-1 which is caused by the vibrations of bonds C = C of the aromatic ring, and the measure of the content of alkanes – the area (S2) of band ν = 725 cm-1, which characterizes the oscillation of C-C bonds in the long chains. The ratio of А = S1/S2 is taken as an indicator of aromatizing oils. Naphthenic structures are not detected by the IR spectra. For methane oils A 500 °С). 3. Higher-boiling and residual fractions of oil contain a significant amount of heteroorganic-resin-asphaltene compounds and metals, and their penetration by distillation into distillates sharply worsens their performance and significantly complicates their subsequent processing. This fact shows the importance of organization of distinct phase separation. 4.1.3. Preparation and processing of gas

The following indicators are used to assess the quality of natural gas: Moisture contents. Moisture promotes corrosion of pipes and equipment, as well as formation of crystalline hydrates. To avoid this,

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Actual ecological aspects of petrochemical manufactures

the gas dew point on moisture must be a few degrees below the lowest temperature during transportation. For example, at a pressure of 5.5 MPa the dew point should be equal to 270 K during the summer period and to 263 K during the winter period in the moderate and hot climatic zone. Hydrogen sulfide content. The presence of hydrogen sulfide in the natural gas causes corrosion of pipes, fittings and equipment and air pollution. The amount of hydrogen sulfide in the gas should be not more than 0.02 per 1 m3. There are dry (hydrate of iron oxide and absorbent coal) and wet (ethanolamines) methods of gas purification from hydrogen sulfide. Carbon dioxide. In the dry gas COgaseous forms a ballast mixture, reducing the heat of combustion. The content of COgaseous in the gas should not exceed 2%. Content of oxygen. In natural gases oxygen is absent, but it can appear in the gas at a pipe purge. The presence of oxygen in the gas can lead to formation of explosive mixtures. No more than 1% of Ogaseous is allowed in the gas. The presence of sulfur. The introduction of mercaptan sulfur in an amount of 16 g per 1000 m3 of gas gives smell to the gas. The maintenance of mechanical impurities in gas is admissible no more than 0.1 g on 100 m3. Impurities contribute to wear and tear of pipes, equipment and clog the instrumentation. Hydrocarbon gases are subjected to a pre-preparation for processing. They are purified from mechanical impurities (dust, sand, and the corrosion products of pipelines), dried, purified from hydrogen sulfide and carbon dioxide. Specific features of gas preparation and processing: 1. A decrease in the formation pressure during operation reduces the raw gas pressure at the entrance to the installation of its preparation. 2. To maintain the required pressure, auxiliary equipment (boos­ ter – compressors, pumps, separators) is required. 3. As a result of decreasing the reservoir pressure, the composition of the extracted gas changes considerably: the concentration of

Chapter 4. Basic concepts of oil and gas processing. Methods of crude oil ...

light hydrocarbons increases and the concentration of hydrocarbons with C5 and higher increases. The composition of condensate in gas condensate fields also changes. 4. As a result of changes in the composition of the crude gas and condensate during operation, the material flows in the main technological devices and thus the mode of operation (pressure, temperature) change. Therefore the choice of the scheme and technology of the gas conversion process is a very complicated problem. Technical and economic analysis of the situation is needed. The general principle of training schemes for gas processing is two steps. 1 step – Gas from the wells is directed to the installation of complex gas preparation (ICPG). 2 step – Gas passes through a complex of technological installations for separation of harmful (sulfur compounds) and undesirable (nitrogen, carbon dioxide, moisture) impurities, gas condensate (hydrocarbons from propane and higher), for stabilization of separation of a broad fraction of light hydrocarbons (BFLH) and natural gasoline, and isolation helium from dry gas. BFLH is a product of processing of associated petroleum gas and gas condensate. It is a mixture of liquefied petroleum gas (propane + butane) and heavier hydrocarbons (C5 and higher). The ratio of normal and iso-hydrocarbons in the BFLH corresponds to the composition of the feedstock. The main difficulties of the choice of the scheme are associated with the second stage where the sequence of technological stages is determined by the following parameters: – composition of the initial gas; – requirements to quality and range of the finished products of its processing; – requirements of minimum energy consumption; – width of range of operational stability at changes of quantity and composition of the initial gas.

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Actual ecological aspects of petrochemical manufactures

The problem of gas preparation also includes removal of gas condensate, water and shallow particles of rock and products of corrosion. Purification of gases from mechanical impurities is carried out by a dry and wet dust cleaning. For dry cleaning cyclones, precipitation devices and baghouse filters are used. For wet gas cleaning scrubbers, wet cyclones, rotary washers are used. Drying is carried out by absorption by means of glycols and adsorption on silica gels or zeolites. Cleaning from carbon dioxide and compounds of sulfur is carried out by the absorptive methods with amines (monoethanol amine, diethanol amine). From the gases condensates gasoline is removed, i.e. topping is carried out. 4.2. General description of the refinery processes

Refinery is an enterprise for production, based on the transformation of oil, fractions and petroleum gases into marketable petroleum products and raw materials for the petrochemical industry (Fig. 11).

Figure 11. General view of the oil refinery

This production enterprise represents a set of physicochemical and technological processes and operations including preparation of raw materials, their primary and (or) secondary processing.

Chapter 4. Basic concepts of oil and gas processing. Methods of crude oil ...

The main function of the refinery is petroleum refining into gasoline, aviation kerosene, fuel oil, solar oil, lubricating oils. In addition, 12 – 16 more principal components are produced from petroleum at modern oil refineries. In general, the refinery is characterized by the following key indicators: – Processing volume (in thousands tons a year). – Depth of processing, the product range and its quality. Territorial position of the oil refinery The choice of the territorial arrangement of a future oil refinery is determined by the following criteria: – proximity to large-scale deposits (for future increase in production capacities); – a developed infrastructure (proximity to power lines, a little distance from the industrial centers, a large distance from the specially protected natural territories); – climatic conditions of the territory; – road location for product sales; – geographical location of competing companies. The production cycle of the oil refinery usually consists of preparation of raw materials, primary distillation of petroleum and secondary processing of oil fractions. Prices of oil products at various oil refineries differ from each other. The oil refinery represents a set of basic petrotechnological processes (installations, shops, blocks), and also the auxiliary and serving services providing normal functioning of the production enterprise (commodity and raw materials, mechanical-repair shops, the instrumentation and automated control systems shop, vapor-, water – and power supply, shop and factory laboratories, etc.). A distinctive feature of the refinery is production of a variety of products from the same source of petroleum feedstock. In most processes mainly only components or intermediates are produced. The final marketable oil products are usually obtained by compounding several components produced at this refinery and additives and dopants.

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Actual ecological aspects of petrochemical manufactures

Oil refining is a continuous production, and the working period of production enterprise between major overhauls in modern plants is about 3 years. At a design stage of the oil refinery the second group of indexes defines the choice of technologies for producing the corresponding products. The complete structure of the refinery comprises the sequence of basic processes: – supply of petroleum crude; – fractional distillation; – chemical treatment; – cleaning and mixing; – storage of finished products; – transportation of products. Currently, the following products are manufactured at the refinery (Table 7): 1) Gasoline; 2) Diesel fuel; 3) Fuel oil (masut); 4) Construction bitumen; 5) Technological fuel; 6) Gases; 7) Sulfur; 8) Lubricating oils; 9) Petroleum coke; 10) Petrochemical feedstocks. Table 7 Classification of the refineries depending on the produced oil products Classification

Fuel and petrochemical oil refineries

Output products combustible gases, motor oil, bitumen, petroleum coke petroleum oils, lubricants, solid paraffins different types of fuels, hydrocarbon materials, production of petrochemistry – polymers, reagents, and so forth.

Refinery (Petrochemical Complex) of fuel and oil-petrochemical profile

different types of fuels, oils, lubricants, products of petrochemistry

Fuel refinery Fuel and oil refinery

Chapter 4. Basic concepts of oil and gas processing. Methods of crude oil ...

There are two methods of oil refining: primary (separation) and secondary (conversion). In modern refineries the basic primary process is separation of crude oil into fractions, i.e., its distillation. Raw materials for processes of secondary petroleum refining (conversion) are the oil products obtained in primary petroleum refining (separation processes). The sources of raw materials for conversion processes are presented in table 8. Products of primary petroleum refining (separation processes) Name 1 Stabilization reflux

Boiling intervals Where it is selected (composition), ºC 2 3 Propane, butane, Stabilization unit isobutane

Stable straightrun gasoline (naphtha) Stable light gasoline

b.b.*-180

Gasoline redistillation

b.b.-62

Stabilization unit

Benzene

b.b.-62-85

Gasoline redistillation

Toluene

85-105

Gasoline redistillation

Xylene

105-140

Gasoline redistillation

Raw materi85-180 als of catalytic reforming Heavy gasoline 140-180

Gasoline redistillation

Kerosene component

Atmospheric distillation

180-240

Gasoline redistillation

Table 8

Application (in the preference order) 4 Gas fractionation, commercial products, technological fuel Gasoline mixing, commercial products Isomerization, gasoline mixing, commercial products Production of the corresponding aromatic hydrocarbons Production of the corresponding aromatic hydrocarbons Production of the corresponding aromatic hydrocarbons Catalytic reforming Mixing of kerosene, winter diesel fuel, catalytic reforming Mixing of kerosene, diesel fuels

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Actual ecological aspects of petrochemical manufactures 4 Hydrotreating, mixing of diesel fuels, fuel oils Fuel oil 360– f.b.** Atmospheric Vacuum distillation, distillation (residue) hydrocracking, mixing of fuel oils Vacuum gasoil 360-520 Vacuum distillation Catalytic cracking, hydrocracking, commodity products, mixing of fuel oils Tar 520– f.b. Vacuum distillation Coking, (residue) hydrocracking, mixing of fuel oils * – b.b.– boiling beginning, **– f.b.– final boiling point Diesel

1

2 240-360

3 Atmospheric distillation

The basis of the petrochemical plants is the installations on manufacturing of hydrocarbon gases – ethylene, propylene, butane, as well as the complexes for production of aromatic hydrocarbons – benzene, xylenes. Productions of oxygen-containing substances – alcohols, esters (methyl, t-butyl) are also a part of petrochemical productions. An important place in the structure of petrochemical productions is occupied by productions of high-molecular compounds: polyethylene, polypropylene. Processes of destructive petroleum refining intended for changing of its chemical composition by thermal and catalytic methods refer to the second types (conversion processes): catalytic cracking, reforming, an isomerization, hydrotreating, etc. According to their directions, all the conversion refining processes can be divided into 3 types (table 9): The deepening processes: catalytic cracking, thermal cracking, delayed coking, hydrocracking, bitumen production, etc. The ennobling (upgrading) processes: reforming, hydrotreating, isomerization, etc. Other processes: processes for the production of oils, MTBE, alkylation, aromatic hydrocarbons production, etc.

Chapter 4. Basic concepts of oil and gas processing. Methods of crude oil ... Table 9

Processes of petroleum refining Process title

Method

1 2 Fractioning processes Atmospheric Thermal distillation Vacuum distillation

Thermal

Aim 3 Fractions separation Separation without splitting

Initial raw materials 4

Products 5

Desalinated Gas, gasoline, petroleum crude distillate and the residue Rest of a Gasoil, oil distilcolumn of late, the residue atmospheric distillation

The conversion process – decomposition Catalytic crack- Catalytic For gasoline Gasoil, distillate Gasoline, feed ing improving of coke stock of oil products Coking Thermal For the The residue, Naphtha, gas oil, vacuum heavy oil, tar coke residues conversion Hydrocracking Catalytic Convertion Gasoil, oil after The lighter and to lighter cracking and higher quality hydrocarresidues products bons Steam reforming Thermal/ Hydrogen Desulfonated  Hydrogen, СО, of hydrogen catalytic production gas, O2, steam CO2  The steam Thermal For splitting Heavy fuel / The crackinged cracking of large distillate of naphtha, coke molecules a column of residues atmospheric distillation Light cracking Thermal For the The residue The distillate, the viscosity from cracking residue  reducing atmospheric distillation column Conversion processes – Combining Alkylation Catalytic To combine Isobutane / ole-  Isooctane the olefins fins of cracking (alkylate) and isopar- unit affins

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Actual ecological aspects of petrochemical manufactures 1 Preparation of the lubricant grease Polymerization

2 Thermal Catalytic

3 To combine soaps and oils To combine two or more olefins

4 A lubricating oil, a fatty acid

5 The lubricant grease

Olefins of crack- High-octane ing unit naphtha, components of petroleum products

The conversion process – Change / regrouping Catalytic Catalytic To imNaphtha of reforming prove the installation of a low-octane coking/ naphtha hydrocracking plants Isomerization Catalytic To transButane, pentane, form hexane a straight chain of hydrocarbons to branched Treatment processes (purification) Cleaning with Absorption To remove Sulphur dioxide, amine acid hydrocarbons pollutants with CO2 and H2S Desalting Absorption To remove Crude oil (pretreatment) pollutants Drying and Absorption / To remove Liquid hydrocleaning from thermal H2O and carbons, liquethe active sulfur sulfur com- fied petroleum pounds gas, the alkylated feedstock Extraction by Absorption To improve Circulating gas furfurol the middle oil and a feeddistillate stock of oils and oils Hydrodesulphu- Catalytic To remove High-sulphurous risation sulfur and residue / gasoil pollutants Hydrotreating Catalytic To remove The residues, impurities the hydrocar/ saturated bons of cracking hydrocarbons

High-octane product of reforming/ aromatic compound Isobutane/pentane/ hexane

Acid-free gas and liquid hydrocarbons Desalinated crude oil Purified from sulfur and dried hydrocarbons High-quality diesel and lubricating oil Desulphurisationed olefins Raw materials for the cracking installation, distillate, lubricating oil

Chapter 4. Basic concepts of oil and gas processing. Methods of crude oil ... 1 Extraction by phenol

2 3 Absorption / To improve thermal an indicator of viscosity of oils, color Deasphalting by Absorption Asphalt solvent removal Dewaxing by solvent



Cooling / filtering

For removing wax from the lubricating oil Extraction by Absorption / Separasolvent precipitation tion of unsaturated aromatics Cleaning from Catalytic For removal the active sulfur H2S, mercaptans transformation

4 5 The basic comHigh-quality ponents of the oil lubricating oil feedstock The residue of vacuum distillation column, propane Lubricating oil of vacuum distillation tower

Heavy component of lubricating oil, asphalt Dewaxed lubricant base components

Gasoil, reforming High-octane product (reforgasoline mate), distillate Crude distillate / gasoline

High-quality distillate / gasoline

Questions for self-checking: 1. List the features of gas preparation and processing. 2. Name the general principle of training schemes for gas processing. 3. Tell about two steps of gas processing. 4. What is the broad fraction of light hydrocarbons (BFLH)? 5. What parameters influence the sequence of technological stages on the second step of gas processing? 6. Explain the features of gas purification from mechanical impurities. 7. Name two stages of oil preparation for processing. Explain the features of every stage. 8. What is the main purpose of oil and condensate stabilization? 9. Explain the features of stabilization of gas condensate. 10. Explain the concepts «big breath» and «small breath». 11. List the methods of dealing with hydrocarbons loss. 12. What is degassing? Explain the stages of degassing. 13. Explain the schematic diagram of the installation of the oil stabilization and of BFLH distillation. 14. Tell about changes in petroleum composition after stabilization. 15. What is distillation? 16. Explain the features of the different types of distillation.

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Actual ecological aspects of petrochemical manufactures 17. What is the essence of distillation with dephlegmation and distillation with rectification? 18. Explain the key diagram of the block of atmospheric distillation of petroleum of AT. 19. Describe the VT installation. 20. Explain the features of oil as a raw material of distillation processes. 21. What is a refinery? 22. List the main processes of the refinery. 23. Tell about classification of refineries. 24. Tell about a territorial position of oil refinery. 25. What is the production cycle of oil refinery? 26. Explain the purpose of petroleum refining. 27. Give the definition of the primary and secondary methods of refining. Compare these methods of oil refining. 28. List the products of primary petroleum refining (separation processes). 29. List the secondary refining processes (conversion processes). 30. List the conversion processes of oil (decomposition and change/regrouping): aim, raw materials, products. 31. List the treatment processes (purification): aim, raw materials, products. 32. List the deepening processes, the ennobling processes of the refinery.

Chapter 5

OIL AND GAS EMISSIONS TO THE ATMOSPHERE, SOIL AND WATER

5.1. Impact of oil and gas emissions on the state of nature and human health

Enterprises of the fuel and energy complex, including the oil refining and petrochemical industries, are the largest source of environmental pollution in the industry. Enterprises of the petrochemical industry, working in the regular mode, inevitably pollute the atmospheric air and natural waters. About 48% of emissions of harmful substances in the atmosphere, 27% of dumping of the polluted sewage, over 30% of the formed solid waste and up to 70% of the total amount of emission of greenhouse gases fall to the petrochemical enterprises. The most vulnerable environmental object in this case is the atmospheric air polluted by huge masses of toxic compounds and greenhouse gases. The largest are the emissions of hydrocarbons into the atmosphere. Oil and petroleum products are among the most harmful chemical pollutants, as indicated in the International Convention for the Prevention of Marine Pollution by Dumping of Wastes, adopted in late 1972. In the modern world, the consumption of oil in all its forms costs an astronomical sum of $ 740 billion annually. And the cost of oil pro91

92

Actual ecological aspects of petrochemical manufactures

duction is only 80 billion dollars. Hence, the desire of the oil monopolies to acquire at their disposal new and new deposits of black gold. In connection with the growth of production, transportation, processing and consumption of oil and oil products, the scale of environmental pollution is expanding. Existing refineries are designed to process millions of tons of oil and are therefore an intense source of environmental pollution. The air pollution zone of powerful refineries extends over a distance of 20 km or more. The amount of released harmful substances is determined by the capacity of the refinery and is (percentage of the plant’s capacity): hydrocarbons 1.5 -2.8; hydrogen sulphide 0.0025 – 0.0035 for 1% sulfur in oil; carbon monoxide, 30 – 40% by wt. of combusted fuel; sulfurous anhydride – 200% of the mass of sulfur in the combustible fuel. Most of the losses of hydrocarbons enter the atmosphere (75%), water (20%) and soil (5%). Sources of harmful substances in the oil refining industry are technological installations, apparatuses, units, pipes, ventilation shafts, reservoir breathing valves, open surfaces of treatment plants. Refining related to the production and use of substances with specific properties (explosiveness, flammability, toxicity) often creates situations, the consequences of which negatively affect the human health and the environment. The vast majority of substances used in oil refining and petrochemicals have fire and explosive, harmful (toxic) and carcinogenic properties. The main feature of the enterprises for processing hydrocarbon raw materials is the presence of fire and explosion hazardous products and raw materials that create the danger of major accidents. To assess the fire and explosion hazard of technological installations, a statistical analysis of major accidents, fires and explosions occurring at hazardous enterprises is required. Note that, despite the improvement of fire and explosion safety systems, the number of accidents is constantly increasing. In tables 10, 11 statistical data on the major accidents in the oil refining and petrochemical industries of various countries are given as an example. It has been established that major accidents and accompanying fires and explosions in industries associated with the

Chapter 5. Oil and gas emissions to the atmosphere, soil and water

processing of hydrocarbon feedstock are in most cases due to leaks of combustible liquid or hydrocarbon gas. The impact of use of hydrocarbon systems on megacities is manifested in two ways. Firstly, the motor transport – contamination with combustion products of motor fuels, fuel spills, lubricating oils, etc. In addition to pollution of the city’s atmosphere, the automobile complex contributes significantly to the pollution of water and soil (suspended particles, petroleum products, organic solvents, heavy metals and their salts). Secondly, there is a powerful impact on the part of enterprises for processing hydrocarbon systems. The development of cities and industrial regions, as well as urban policy of the last decades, led to the fact that most of the enterprises for processing hydrocarbon systems, including oil refining and petrochemical industries, were located in the urban metropolitan areas. The negative role of technogenic pollution considerably affects human health. According to statistical data, owing to technogenic air pollution, health of the population has worsened by 43-45%. Therefore for such productions environmental protection and increase in industrial safety should become priority activities. Enterprises of the oil refining industry emit significant amounts of gases and vapors (sulfur oxides, carbon monoxide (II), nitrogen oxides, hydrogen sulfide, ammonia, hydrocarbons, oxygen and nitrogen containing organic compounds, organic and inorganic dust, resinous substances) into the atmosphere. Systematic leaks and emergency spills of oil products on the territories of oil refineries and oil depots contribute to soil contamination and formation of technogenic lenses of petroleum products in the soils of the aeration zone and on the surface of groundwater. Volatile components of petroleum and petroleum products, sulfur oxides, nitrogen and carbon, formed during combustion of oil residues, as well as products of incomplete combustion – soot, polycyclic aromatic hydrocarbons (PAH), etc., enter the atmosphere from petrochemical facilities.

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By the degree of ecological danger, the pollutants, which are most often found in the sources of pollutant emissions in the objects of oil industry, can be arranged in the following decreasing sequence (1): H2S → CnH2n+2→ SO2→ SO3→ NO → NO2→ CO → NH3→ CO2 (1) Control of such emissions is hampered by the fact that they come from a huge number of sources distributed over a large area, therefore, the use of any treatment facilities is excluded and the task of reducing emissions must be addressed by technological measures, for example: – replacement of tanks with hipped roofs by the tanks with floating roofs or pontoons; sealing of technological equipment and communications; – application of automatic control of technological processes, which does not allow violation of parameters that regulate pressure and therefore prevents the activation of safety valves; – use of a safety valve monitoring system; application of a developed flare system with full collection and use of waste gases; – sealed discharge-filling in railway tanks; – replacement of open oil traps with sealed and others. Table 10 Major accidents at the enterprises for processing of hydrocarbon raw materials Substance, nature of accident 1 2 Germany, Explosion of a cloud of Ludwigshafen butadiene and butylene Germany, Explosion of a cloud of Ludwigshafen dimethyl ether Explosion of the France, Faisen storage of liquefied petroleum gas Explosion of the United States, Port storage of liquefied Hudson petroleum gas Place

Emission, Number of Number of t deaths injured 3 4 5 20

57

439

30

207

300

200

18

81

70

0

7

Chapter 5. Oil and gas emissions to the atmosphere, soil and water 1 South Africa, Potchefstroom United States, Decatur Netherlands, Beck England, Fliksborough USA Colombia, Catagena Colombia, SantaCruz Spain, San Carlos Mexico, Mexico City Brazil, Cubatão Russia, Yaroslavl Russia, Krasnoyarsk Russia, Ufa

2 Leakage of liquid ammonia from the storage

3

4

5

-

18

64

Propane leak

63

7

152

3-5

14

107

30-50

28

89

5.5

14

45

Ammonia leak

-

30

22

Explosion of methane

-

52

-

38

215

780

-

452

5,250

-

500

7,000

3.3

6

13

-

4

5

-

2

8

Explosion of a cloud of propane Explosion of a cloud of cyclohexane Propylene emissions

Explosion of a cloud of propylene Explosion of the tank (liquefied gas) Explosion of gasoline Explosion������������� of���������� ������������ hydrocar��������� bon gases Explosion of hydrocarbon gases Emission and explosion of hydrocarbon gases

Table 11 Direct economic losses from major accidents at the US refineries City, state 1 Linden, New Jersey Billing, Montana Avon, California Avon, California Baton Rouge, Louisiana Texas City, Texas Texas City, Texas Borger, Texas

Installation, process 2 Hydrocracking Alkylation Coking Coking Catalytic cracking Alkylation Alkylation Alkylation

Direct losses, mln. USD 3 94.6 14.5 22.9 13.9 18.2 99.6 40.3 53.8

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Actual ecological aspects of petrochemical manufactures 1 Avon, California Torrance, California Norco, Louisiana Richmond, California Martinez, California Warren, Pennsylvania Chalmette, Louisiana Port Arthur, Texas Lake Charis, Louisiana Sweeny, Texas Beautmont, Texas Wilmington, California

2 Catalytic cracking Alkylation Catalytic cracking Hydrocracking Catalytic cracking Catalytic cracking Hydrocracking Atmospheric-vacuum tube (AVT) Catalytic cracking Hydrotreating Atmospheric-vacuum tube (AVT) Hydrotreating

3 60.7 16.9 327.0 100.7 53.0 26.3 15,8 27.5 23.5 51.0 15.3 72.7

Fire and explosion hazard of individual blocks of external process units is determined by the nature of the raw materials and finished products, the parameters of the process and the features of the equipment. Separate plant elements, for example, open tube furnaces, are sources of not only formation of explosive mixtures, but also of their ignition (Fig. 12).

Figure 12. The fire at oil refinery

Chapter 5. Oil and gas emissions to the atmosphere, soil and water

The distribution of the number of accidents by certain types of technological equipment is presented in Table 12. A very important factor is the detection of the gassed air environment of the territory of enterprises in the early stages of the accident. Table 12 Distribution of the number of accidents by types of process equipment Equipment Technological pipelines Pump stations Capacitive apparatus (heat exchangers, dehydrators) Furnaces Rectification, vacuum and other columns Industrial sewerage system Tank farms

Number of accidents, % 31.2 18.9 15.0 11.4 11.2 8.5 3.8

Similar is the situation with emissions into the atmosphere of combustion products from process units and flare facilities. And here technological measures should be provided to protect the atmosphere from carbon monoxide (II) and sulfur dioxide. Emissions of carbon monoxide (II) can be reduced by ordering the combustion process, as well as catalytic afterburning to carbon dioxide. Reduction of sulfur dioxide emissions can be achieved by preliminary desulfurization of the fuel burnt. By the accepted technology of processing sulfur oil, in the course of catalytic hydrotreating hydrogen sulfide and other sulfur compounds are extracted in the form of commodity products – sulfur or sulfuric acid, and emission of hydrogen sulfide in the atmosphere is considerably reduced. Release of hydrogen sulfide from barometric condensers can be eliminated with their replacement by superficial condensers. Other sources of emission of hydrogen sulfide can be reduced by sealing improvement. Dust emissions are more local than gas and are easier to catch. Dust is formed during transportation of catalysts and adsorbents, their regeneration, grinding, drying, etc. In the processes in fluidized bed reactors (catalytic cracking, dehydrogenation of butane), the catalyst

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particles in case of repeated use are reduced in size and are taken out with the gas flow. In oil refineries to remove dust particles, dust precipitation chambers, cyclones, and rotary apparatuses are used. Measures taken in oil refineries to protect the air basin should be aimed at increasing the production culture, strict adherence to the technological regime, improving technology to reduce gas generation, maximizing the use of generated gases, reducing hydrocarbon losses at the facilities of the general plant, reducing emissions of harmful substances during adverse weather conditions, development and improvement of methods for monitoring and cleaning emissions into the atmosphere. The chemical, oil refining and petrochemical industries are among the most water-intensive sectors of the national economy. The complexity of solving the problem of rational use of water resources and preventing pollution of reservoirs by sewage is due to the peculiarities of these sectors: – huge water quantities involved in production of material resources and manufactured products; – diversity of applied technologies, manufactured products and resulting wastes; – widespread use of water for production purposes and lack of technological solutions for its replacement. The composition of production sewage depends on the nature of water use in technological process. Sewage formed at modern oil refineries (oil refinery) contains impurities that don’t refer to the category of strongly toxic: chlorides, sulfates, nitrates and phosphates of sodium, potassium, calcium, ammonium, magnesium, iron, copper, organic products, suspended substances, oil products, surfactants, oils, etc. Wastewater from oil refining, petrochemical and chemical industries, in addition to dissolved organic and inorganic substances, may contain colloidal impurities, as well as suspended substances, the density of which may be more or less than the density of water. In some cases, the wastewater contains dissolved gases. Sewage may contain in their composition fire-hazardous and explosive substances, and also compounds, aggressive in relation to

Chapter 5. Oil and gas emissions to the atmosphere, soil and water

pipelines, collectors, and cleaning equipment. In certain cases sewage contains substances possessing a pungent unpleasant smell or surfactants leading to foaming, etc. Today, the most traditionally applied approach in the organization of reduction of environmental pollution is the construction of treatment facilities. However, this is expedient only for adapting existing production facilities to new environmental requirements, since it leads to a significant increase in capital and operating costs and reduces real waste. The main direction in the solution to the problem of ecological safety should be considered as greening of chemical productions, i.e. creation of environmentally friendly, waste-free, more precise, lowwaste technological productions in which all components of raw materials and energy are most rationally and completely used, and normal functioning of the environment and natural balance are not violated. It is necessary to distinguish the following main directions in the implementation of environmentally friendly technological processes, including petrochemical processes: 1. Complex use and deep processing of raw materials. Production should be as resource-consuming as possible (resource-saving technologies), carried out with a minimum of raw material and reagent costs per unit of output. The resulting semi-finished products should be transferred as raw materials to other industries and completely processed. An example of this approach is the technology of deep oil refining. 2. Optimal use of energy and fuel. Production should use minimum energy and fuel per unit of output (energy-saving technologies) and, consequently, thermal pollution of the environment should be also minimal. Energy saving is promoted by integration and energy-technological combination of processes; transition to continuous technologies; improvement of separation processes; use of active and selective catalysts allowing us to carry out processes at the lowered temperature and pressure; rational organization and optimization of thermal schemes and schemes of recovery of energy potential of the waste streams; decrease in hydraulic resistance in systems and losses

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of heat to the environment, etc. Petroleum refineries and petrochemical enterprises are major consumers of fuel and energy. In their energy balance, direct fuel accounts for 43-45%, heat energy – 40-42% and electric – 13-15%. The useful use of energy resources does not exceed 40-42%, which leads to over-consumption of fuel and formation of thermal emissions to the environment. 3. Creation of fundamentally new low-waste technological processes. This can be achieved by improving catalysts, machinery and technology production. Low-waste processes are more efficient than processes with expensive wastewater treatment plants. It is more economical to obtain a small amount of very concentrated waste, which can be recycled or disposed by a special technology, than a large volume of highly diluted waste discharged into the biosphere. 4. Creation and implementation of closed water use systems, including (or minimizing) fresh water consumption and wastewater discharge into water bodies. 5. Assurance of high operational reliability, tightness and durability of functioning of equipment and all systems of productions. Minimization or exception of probability of accidents, explosions, fires and emissions of toxic agents in environment. Development of the automated systems of productions and complexes ensuring ecological safety. 6. Assurance of high quality of targeted products used in the national economy. Ecologically clean should be not only the technological processes themselves, but also the products produced in them. Thus, motor fuels must satisfy the increased environmental requirements for the content of sulfur compounds, aromatic hydrocarbons, harmful additives, for example, ethyl liquid, etc. 7. Use of new environmentally friendly products from alternative sources of raw materials, for example, oil and natural gas, oxygen-containing hydrocarbons (alcohols, ethers) and hydrogen in road transport. The transfer of a part of vehicles to alternative fuels is considered in many countries of the world as a radical measure of reducing harmful emissions of cars, improving the air basin of large cities, while simultaneously significantly expanding the resources of motor fuels.

Chapter 5. Oil and gas emissions to the atmosphere, soil and water

Improvement of the environment is also promoted by constructive improvement and ecologization of the mobile equipment thanks to preferential use of diesels, in comparison with petrol cars; increase in fuel efficiency of vehicles – preferential production of cars of small and especially very small classes, mini-tractors. If to consider the adverse effect of oil, gas and coal on the living conditions on Earth, it is possible to conclude that in ecological terms the atomic energy is the cleanest form of energy. But after the accident in Chernobyl such an approach would be a little lightweight. Even a partial liquidation of its consequences in Belarus alone will cost, according to expert estimates, 16 annual budgets of the country. There are problems of ensuring nuclear and radiation safety, neutralization of radioactive waste, conversion in the field of nuclear weapons. 5.2. Climate change on earth 5.2.1. Impact of reduction of the number of forests on ecology

Let us consider in some detail such a manifestation of global technogenesis as a mass reduction of forests on the planet. Their disappearance and degradation are associated with the following factors: a) industrial wood cutting in big scales seldom followed by the corresponding works on reforestation; b) expansion of scales and areas of preparations of wood fuel, especially in developing countries; c) strengthening of the demographic press, “expansion” of urban and rural settlements; d) displacement in the vast areas of natural forests by monocultural artificial plantations – plantations of rubber plants, oil palm trees, etc.; e) conservation of peri-urban farming in the underdeveloped countries (primarily in the states of tropical Africa); f) transformation of large forest areas into pasture lands for largescale commercial livestock (especially in South America);

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g) overgrazing of livestock in tropical dry forests, xerophilous light forests and stony-lenticular formations; h) strengthening the impact of factors of industrial origin; i) strengthening the recreational use of forests, as well as expanding the scale of hunting. It is quite obvious that these factors influence differentially depending on the type of the country and territories. Some of them are inherent only to developing countries (overgrazing, practice of slash of fire agriculture, etc.), while in industrially developed countries the main factor of forest degradation is undoubtedly the industrial factor (logging of commercial wood, acid rain, etc.). A very specific role in the modern world is played by tropical forest formations. It is known that the Earth’s forest cover is one of the most important accumulators of living matter, which keeps a number of chemical elements and water in the biosphere; it actively interacts with soils, hydrosphere and atmosphere, determines the oxygen and carbon balance. All these functions are most clearly associated with tropical forests. This is one of the most complex ecological systems on the planet, where the climate, soils, vegetation and fauna are components of a single, exceptionally complicated, natural complex. Many scientists argue that the rainforest is non-renewable and irreplaceable (and dies as a single organism, as “a huge magnificent animal”). Wet tropical forests are the richest biome in the world, containing about half of all terrestrial fauna and flora species – a huge stock of genetic resources (there are about 5 thousand species of tree species alone, while in the forests of Western Europe there are only about 250 species). It is the forest formations of the tropics that are recognized as the center of evolutionary activity on Earth and with their disappearance a huge sphere of potential human knowledge can disappear. Meanwhile, recent space surveys have shown that the belts of tropical rainforests on the globe have almost disappeared! They broke up into separate arrays, the main of which are in the basins of the Amazon and Congo rivers. It is possible to speak specifically about the geoecological, socioecological and economic functions of tropical forests:

Chapter 5. Oil and gas emissions to the atmosphere, soil and water

1. Absorption, accumulation and release of CO2, O2 and other chemical elements. 2. Absorption of aerosols and noise. 3. Absorption, accumulation and release of water. 4. Absorption and conversion of radiation and heat energy. 5. Climate regulation. 6. High quality tropical wood with beautiful texture, wide color range, comparative ease of processing. Assessment of socioecological functions is ambiguous due to the climatic discomfort of rainforests, which does not always contribute to the “habitation” of this environment. Thus, the mass data on rainforests is one of the most eloquent indicators of the characteristics of technogenesis. Specific energy production can serve as the other generalizing indicator. By the roughest estimates, during the development of humanity, since the new Stone Age, it has grown not less, than by 5,000 times. A less impressive but a more objective picture of the dynamics of one aspect of technogenesis is given by the characteristic of changes in the world land use. Virtually, all countries of the world increase the area of built-up land, expanding man-made areas. From the point of view of atmospheric emissions, chemical compounds of carbon (primarily carbon monoxide and carbon dioxide) are of greatest interest for the characterization of technogenesis. Since these compounds are formed mainly as a result of fuel combustion, the amount of their emissions is closely correlated with the level of industrial development of countries. It is also necessary to note the reduction of biological diversity. 5.2.2. Global warming. Greenhouse gases

The aggravation of the global environmental crisis is connected with the demographic explosion and the need to meet the growing material needs of people, which causes expansion of the scale of economic activity and leads to an increase in the anthropogenic pres-

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sure on the environment. As a result, the problems of global environmental pollution, global climate change, destruction of stratospheric ozone are exacerbated, the planet’s natural resources are depleted, the number of man-made disasters increases, the probability of a loss of stability in the biosphere, the economic capacity of which is finite, is increasing. In 1990, 49 Nobel Prize laureates recognized the threat of climate change as the most serious global problem associated with the survival of modern civilization. The Intergovernmental Group of Experts on the UN Climate Change (IPCC), which is a forum of many thousands of scientists of the world, provides a systematic assessment of the problem of global warming and develops approaches to its solution. The climatic system of Earth includes the atmosphere, the ocean, the land and the biosphere. The conditions of the environments entering this complex system are described by such parameters as temperature, pressure, density, speed of movement, etc. The “behavior” of the climate system, which is characterized by cyclic processes, can be characterized by more complex parameters: – the dynamics of large-scale circulation of the atmosphere and the ocean; – the frequency and strength of extreme meteorological phenomena; – the boundaries of habitats of living organisms and a number of other parameters. Climate is defined by a set of states passed by a climatic system over a characteristic period of several decades and frequency of their recurrence. Climate change at the global level or on this geographical terrain consists in the change of the long-term type of weather. Global climatic, biological, geological, chemical processes and natural ecosystems are closely related: changes in one process can affect others. An important factor is the interaction between the atmosphere and the ocean, which is the main source of extreme weather events. As the World Ocean occupies most of the planet, its currents and circulation of waters that determine the climate of many densely populated regions of the world. Potentially very dangerous is the change in the

Chapter 5. Oil and gas emissions to the atmosphere, soil and water

circulation of such powerful ocean currents as the Gulf Stream. There is often a feedback between the components of the climate system. With a positive feedback, there is an accelerated growth of the primary disturbance. Global climate change (warming) is associated with an abnormal increase in the natural atmospheric phenomenon, called the greenhouse effect. In the absence of this effect, the average global temperature of the Earth’s surface would be 18 °C. The Ministry of Energy, the Global Environment Facility and UNDP presented a national communication on the climate change in Kazakhstan. If we believe the presented data, climate warming in Kazakhstan is faster than the world average. Thus, for example, in 2016 the temperature anomaly was +1.66 °C in comparison with the average temperatures of 1961-1990. According to the calculations presented in the national communication, it is clear that if the climate change until 2050 will be in accordance with even the most extreme scenario, the water resources in the mountain basins of Kazakhstan can increase by an average of 7%, and in the lowland rivers decrease by 3.8 %. Thus, in the south and east of Kazakhstan, where rivers are fed by glaciers, an increase in water content can lead to increased mudflow and landslide processes. Increased floods and mudslides are a direct consequence of warming. And, most likely, they will happen more often from year to year. The main components of the air – nitrogen, oxygen and inert gases – are transparent both for visible sunlight and infrared rays. However, the energy of the Earth’s radiation, corresponding to the infrared region of the spectrum, is effectively absorbed by other components of the atmosphere – greenhouse gases (GHG), raising the temperature of the surface layers of the atmosphere. The main greenhouse gases include: – water vapor; – carbon dioxide; – methane; – N2O; – a number of technogenic gases.

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Greenhouse gases are stored in the atmosphere for quite a long time, the period of their life is estimated by many decades. The total content of greenhouse gases in the atmosphere is less than 0.5%, but this is enough to create a natural greenhouse effect. Due to this effect, the average global temperature rises to +15 °C. An abnormal increase in the concentration of greenhouse gases in the atmosphere, observed in recent decades, is due to the excess of the inflow over the outflow of these gases and is caused by anthropogenic reasons, that is, related to human economic activity, emissions of greenhouse gases. At present, the contribution of carbon dioxide to the greenhouse effect is about 80%, methane – 18-19%, the remaining 1-2% fall on N2O, some industrial gases and ozone. Although the contribution of water vapor to the greenhouse effect is even greater than the contribution of CO2, no significant deviation of air humidity from the average value was observed. Combustion of coal, oil and natural gas leads to the release of carbon at unprecedented rates encased in these fossil fuels. The current annual anthropogenic emissions amount to more than 23 million tons of carbon dioxide or almost 1% of the total mass of carbon dioxide in the atmosphere. The carbon dioxide caused by economic activity of people joins the natural carbon cycle. Additional anthropogenic intake of carbon dioxide in the atmosphere could be compensated as a result of the biotic regulation by the ecological systems of the biosphere (for example, to be absorbed by the woods). But due to disturbances in the structure of terrestrial biota and the global biochemical cycle of carbon in general, this excess anthropogenic part of carbon dioxide in the atmosphere is constantly increasing. Even with half of the carbon dioxide emissions from anthropogenic activities being absorbed by the oceans and vegetation, atmospheric levels continue to grow by more than 10% every 20 years. Over the past 150-250 years, due to changes in the land use, the amount of biomass and soil carbon has significantly decreased, and, therefore, the carbon stock accumulated in terrestrial ecosystems as a whole. As a result, a large amount of CO2 has entered the atmosphere. The area of forests decreased sharply, especially in the tropics. Graz-

Chapter 5. Oil and gas emissions to the atmosphere, soil and water

ing more and more livestock in developing countries, especially in Africa, has led to the degradation of pastures. All this not only affected the local climate, but also made its negative contribution to the global processes. According to UN experts, the anthropogenic greenhouse effect is 57% due to fuel production and energy production, 20% to industrial production, not related to the energy cycle but consuming fuel, 9% to forest disappearance, and 14% to agriculture. In addition to the anomalous increase in the absolute values of the mean global temperature, a very significant fact is a sharp increase in the rate of its growth. The urgency of the problem of climate change is not so much in the warming, as in the imbalance and destabilization of the climate system. A powerful release of CO2 is a kind of a chemical impulse, quite a strong perturbation for the climate system. The long-term process of the natural evolution of the global climate is imposing ever more tangible changes in the climate system caused by anthropogenic activities. 5.2.3. The effects of climate change

The consequences of global warming can be catastrophic. An increase in the level of the world’s oceans by 0.5-1.0 m as a result of intensive thawing of polar ice will cause flooding of coastal densely populated areas. An increase in the number and intensity of extreme climatic phenomena is expected. The regime of precipitation will change, the number of abnormally hot and humid years will increase, more often and more intensively, hurricanes, storms, tsunamis, floods and droughts will occur. The predicted rates of warming are tens of times higher than the natural rates of temperature growth, which does not correspond to the adaptive capabilities of many species of living organisms, and will lead to the destruction of some ecosystems. The above tendencies quite clearly manifest themselves today. The last two decades are the warmest years since 1866 (the beginning of systematic observations). The increasing damage is caused by natural disasters and is estimated in billions of dollars.

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Food The Intergovernmental Group of Experts on the UN Climate Change (IPCC) connects the most serious negative consequences with the threat of ensuring food security. Climate changes will lead to a decrease in the potential productivity (yields) in the majority of tropical and subtropical regions. With an increase in the average global temperature by a few degrees, there will be a decrease in yields in the mid-latitudes that cannot be compensated by changes in high latitudes. In the first place, drylands will suffer. An increasing CO2 concentration can potentially be a positive factor, but it is likely to have more secondary negative effects, especially where agriculture is conducted extensively. Lack of water resources Climate change leads to an unfavorable redistribution of precipitation. In the northern and middle latitudes with a fairly good regime of precipitation, their number will increase. Central continental regions are likely to become even drier. The interannual variability of rainfall will increase sharply. The unfavorable redistribution of precipitation will exacerbate the acute problem of providing a number of regions with fresh water. Health of the population The direct impact of heat stress will be felt in the cities where the most vulnerable and poor groups of the population (old people, children, people suffering from cardiological diseases, etc.) will be in the worst situation. Climate change will have far-reaching side effects: the spread of vectors of disease, the decline in water quality, and the deterioration of food quality in developing countries. Ecosystems Some natural systems (glaciers, coral reefs and mangroves, tropical forests, polar and alpine areas) are likely to undergo significant changes, which can cause irreversible losses in their ecosystems. A significant disturbance of ecosystems is expected as a result of fires,

Chapter 5. Oil and gas emissions to the atmosphere, soil and water

droughts, floods, landslides and mudflows, parasite infestations, and appearance of new species for the locality. The general impact on wildlife is twofold: a number of the most numerous species will begin to develop intensively, and rare and vulnerable species will be on the verge of extinction. In general, climate change certainly leads to the loss of biodiversity. For many species of animals and plants, the required migration rate will be higher than their adaptive capacity. As a result, a mean global warming of 30 °C can lead to the loss of biodiversity (for example, for mammals of taiga and mountain ecosystems, losses will amount to 10 to 60% of the number of species). Climate change in the Arctic In the Arctic, climate change is particularly intense. Compared with the rest of the world, the growth rate of the average temperature in this region is twice as high. The ice sheet melts with an unprecedented speed: now it is twice as thin as 30 years ago. If the rate of melting continues, the Arctic ice may not remain in summer 2070. The unprecedented speed with which the Arctic ice melts can lead to the flooding of significant areas, disappearance of certain species and destruction of urban infrastructure. 250 scientists from different countries, working under the aegis of the Arctic Council came to such conclusions. Questions for self-checking: 1. List the characteristic features of oil and gas production 2. Tell about the types of pollution sources in oil and gas production. 3. Explain the role of forests in ecology. 4. Explain the term “greenhouse gases” 5. What is “global warming”? Name the main signs of it. 6. Describe the changes of climate on the Earth during the last decades. Name their causes.

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Chapter 6

CONCEPT OF SUSTAINABLE DEVELOPMENT

6.1. Conclusions of the World experts

The Intergovernmental Group of Experts on the UN Climate Change (IPCC) assessed the risks and consequences for different scenarios. In general, the risks were considered for the lower (1.5-2 °C) and upper (4-5 °C) range of temperature rises by the end of the 21st century. The risk of extinction with relatively little warming will affect only some unique and now endangered ecosystems. In any case, there is a risk of an increase in the number of extreme events, but with significant warming it will multiply. With a smaller change in the average global temperature, only part of the regions on the planet will be affected, while the economic consequences can combine negative and positive factors. In the worst case, warming will affect the vast majority of regions, and the results will be extremely negative. Conclusions of the World Meteorological Organization In the composite report “Our future climate”, the World Meteorological Organization recognizes the very phenomenon of climate change and its largely anthropogenic causes as an established fact. Unambiguously, the danger for mankind of future changes is indicated. Despite the fact that these changes are short-lived on the geological scale, many ecosystems can suffer irreversible damage, and mankind will have to incur huge economic and social costs. To date, the inter110

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national level documents do not specify critical indicators for global warming, that is, the temperature value and the corresponding concentration of carbon dioxide (the main greenhouse gas), which will lead to irreversible catastrophic changes in the world. These may include large-scale agricultural and food problems, water scarcity, drought, morbidity, sea level rise, destruction of the biosphere ecosystems, natural disasters, accelerated melting of the Arctic ice, and disruption of the Gulf Stream flow. Unlike normalized pollutants, greenhouse gases in those concentrations that are observed in the atmosphere and lead to an increase in the greenhouse effect do not have a direct harmful effect on human health and natural systems. Therefore, the traditional normative method of environmental management based on environmental quality standards MPC (Maximum Permissible Concentration) and establishing the maximum permissible emission of toxic or harmful substances MPE (Maximum Permissible Emission) is not adequate to the problem being solved. In the case of greenhouse gases, the determining parameter is the absolute value of emissions for a long time, usually a year. At the same time, it does not matter whether it was a volley or a long-term routine emission, nor does the place of ejection matter. It is the amount of greenhouse gas emissions over a typical period that determines the contribution of the source to the global greenhouse effect, which is due to the very nature of this physical phenomenon. It should be noted that the effect of individual greenhouse gases is summarized and the resultant greenhouse effect is defined by their total action with individual coefficients of global warming. Therefore, the inventory data are expressed in units of CO2 equivalent, and the net effect of all the gases emitted is obtained as the weighted sum of emissions of individual gases with weights reflecting their greenhouse effect. For the unit, the effect of CO2 is adopted, and the emissions of the remaining gases are multiplied by certain global warming coefficients. Also, the greenhouse effect is cumulative and inertial in nature. Cumulation is manifested in the fact that the current intensity of the greenhouse effect is determined not only by the current level of greenhouse gas emissions, but also by their quantity accumulated over the

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previous long period of time. Accordingly, the current reduction in greenhouse gas emissions will not lead to an immediate weakening of the greenhouse effect, but will manifest gradually over a relatively long period of time as the life cycle of the gases having entered the atmosphere is completed. It is obvious that the world community has to provide a timely and proper response to the increasingly pressing problem of the global climate change. For this purpose it is very important: – to provide purposeful influence within the world system, i.e. to start global management of emissions of greenhouse gases; – to create the corresponding institutional environment (“global rules of the game”) supporting standard and legal base and structures of management, scientific, information, financial security, etc. The concept of sustainable development proclaimed by the international community is a conceptual base for the development of international and national policy in the field of the environmental management and environmental protection considering close interrelation of nature protection activity with the economy and the social sphere. 6.2. The documents of the concept of sustainable development

The most important documents of the concept of sustainable development were adopted at the United Nations Conference on Environment and Development, held in 1992 in Rio de Janeiro (CED-92) and at the World Summit on Sustainable Development, held in 2002 in Johannesburg (WSSD – 2002). CED-92 has become one of the most significant events of our time. The World Forum focused attention of statesmen and the world community on the key issue of the inextricable interrelation of the problems of development of modern civilization and preservation of the natural environment. The documents of the Conference state that human civilization is experiencing a turning point in its history. Mankind makes a choice in favor of a balanced approach to the solution

Chapter 6. Concept of sustainable development

of global problems, ensuring the improvement of the living standards of the entire population of the planet, without destroying the environment at the same time. Crucial to this task are the strategies of sustainable development for most countries of the international community, whose responsibility lies on the national governments. The development of a strategy for sustainable development and the mechanism for its implementation should be a key issue on the agenda of the world community for the twenty-first century. WSSD-2002 confirmed the commitment of the world community to sustainable development. The Johannesburg political declaration contains a provision on collective responsibility for strengthening the foundations of sustainable development. The need to strengthen the interrelation between socio-economic development and environmental protection at the local, regional, national and global levels is underlined. The priority objectives of sustainable development are identified: poverty eradication and human development, changing production and consumption patterns, meeting people’s needs for clean water, sanitation, energy, health, food security, and protecting biodiversity and sustainable use of natural resources. The most important document of the summit was the Plan of Implementation of the World Summit, which sets out the timetable for achieving the goals in the socio-economic and environmental areas. CED-92 adopted the United Nations Framework Convention on Climate Change (UNFCCC). The Convention is an important political document in the system of efforts of the world community to ensure sustainable development and action to address the problem of global climate change. UNFCCC is laying the foundations for a policy on greenhouse gas emissions management. 6.2.1. United Nations Framework Convention on Climate Change

The UNFCCC was opened for signature by the Parties in 1992 in Rio de Janeiro and entered into force in March 1994. More than 190 countries of the world are parties to the UNFCCC, including all

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industrialized countries and most developing countries. The countries of the former USSR are also parties to the UNFCCC. The Convention sets the framework for international cooperation in the solution of the climate problem and contains general basic provisions. It provides a detailed justification for the need of an international agreement on the problem of global climate change. In particular, the Convention states: – That as a result of human activities there has been a significant increase in the concentration of greenhouse gases in the atmosphere, which increases the natural greenhouse effect and can have an adverse effect on natural ecosystems and mankind. – It is established that it is necessary to protect the climate system for the benefit of present and future generations of mankind on the basis of justice and in accordance with common but differentiated responsibilities. – The largest share of global greenhouse gas emissions falls on developed countries, which should play a leading role in combating climate change and its negative consequences. The ultimate goal of the UNFCCC is “to stabilize the concentration of greenhouse gases in the atmosphere at a level that would prevent a dangerous anthropogenic impact on the climate system, a level that must be reached in a time sufficient for natural adaptation of ecosystems to climate change that do not jeopardize food production and ensuring further economic development on a sustainable basis”. The sphere of regulation of the Convention is only anthropogenic emissions and sinks of greenhouse gases. The Convention establishes a set of guiding principles for the achievement of the stated goal. The precautionary principle provides that insufficient scientific data certainty should not be used as a reason for delaying the adoption of preventive measures if there is a threat of serious or irreversible damage. The principle “the general, but the differentiated responsibility” assigns to the developed countries the leading role in a solution of the problem of climate change. Other principles concern special problems

Chapter 6. Concept of sustainable development

of developing countries and importance of assistance to sustainable development. Developed and developing countries undertake the general obligations. All Parties to the UNFCCC: – prepare and submit “national communications” containing inventories (results of inventory) of anthropogenic emissions by sources and removals by sinks of all greenhouse gases; – adopt national programs containing measures to mitigate the effects of climate change and develop strategies for adequate adaptation to these changes; – cooperate on scientific and technical issues and promote education, public awareness and exchange of information related to climate change, etc. 6.2.2. Kyoto Protocol to the UN Framework Convention

The Kyoto Protocol to the UNFCCC was adopted in 1997 at the Third Conference of the Parties (COP-3) in Kyoto. The Protocol, like the UNFCCC, is an international political and legal document adopted on the basis of consensus reached by all parties to the UNFCCC. The main objective of the Protocol is to develop and test effective mechanisms that are acceptable to the participants of the Kyoto process to achieve the ultimate goal of the UNFCCC and to obtain a real result, from which it will be possible to accelerate further progress towards the ultimate goal. The scientific validity of the provisions of the Protocol is ensured by the Convention itself and the results of large-scale international scientific activities conducted by the Intergovernmental Group of Experts on the UN Climate Change (IPCC) and other research groups. The existence of a serious threat to the global climate system was recognized as a sufficient basis for the development of the Kyoto Protocol. The highest commitments to reduce emissions were assumed by the countries of the European Union (8%). It is enough for CIS coun-

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tries to keep greenhouse gas emissions at the 1990 base level. The Protocol does not provide for emission limitation commitments for developing countries. The protocol does not aim to achieve stabilization of the concentration of greenhouse gases in the atmosphere during the time of its obligations. Commitments for the period beyond 2012 are not regulated by the Kyoto Protocol and will be determined by additional international agreements. A list of greenhouse gases (GHG) has been established, the total emissions of which will be taken into account when assessing the achievement of emission reduction or limitation targets. It included: – carbon dioxide (CO2); – methane (CH4); – nitrous oxide (N2O); – three groups of long-lived industrial gases. It is recommended to carry out policy “for encouragement of sustainable development” and to take a number of measures on decreasing emissions, such as an increase in the efficiency of energy use, and assisting in reproduction of forest resources and also encouragement of steady forms of agriculture. The Kyoto Protocol provides for flexible mechanisms for its implementation, which make it possible to increase the economic efficiency of the actions of the world community in achieving its goals through international cooperation in the field of reducing greenhouse gas emissions using market mechanisms. Between the countries, the following mechanisms of cooperation can be used: trade in quotas for the emissions of GHG, the projects of joint implementation (PJI) directed to reduction of emissions of GHG and/or to increase in their absorption works in developing countries – the clean development mechanism (CDM) including only financing of projects on reduction of emissions. The transfer of rights to greenhouse gas emissions in the Clean Development Mechanism for carbon trading is a market-oriented regulatory mechanism. Joint implementation of obligations is also possible when Parties that have reached an agreement on joint imple-

Chapter 6. Concept of sustainable development

mentation of their obligations are considered to have fulfilled these obligations provided that their total aggregate anthropogenic greenhouse gas emissions do not exceed the assigned amounts. In practice, these provisions of the Kyoto Protocol are already being used by the European Union, redistributing commitments among its member countries. The Kyoto Protocol and UNFCCC provide for the following conditions, the creation of which is necessary in the countries to participate in the Kyoto mechanisms: – fulfillment of quantitative emission limitation commitments; – adoption of a national action plan and measures to reduce greenhouse gas emissions in accordance with the quantitative commitments taken; – creation of a national system for recording greenhouse gas emissions and sinks; – organization of the national register of registration units of emissions of greenhouse gases; – establishment of quantitative value of a quota for emissions on the basis of data of inventory for 1990; – providing reports in the Secretariat of UN FCCC in the form of National communications; – passing of consideration of reports by the international group of experts and so forth. Compliance with obligations under the Kyoto Protocol is legally binding for each of the Parties. The question of imposition of sanctions on the Parties in the event of their failure to fulfill their obligations has not been finally resolved and is being discussed at international negotiations. To manage the activities under the Kyoto Protocol, a special Implementation Protocol Committee is created, which provides countries with advice and technical assistance in the implementation of the Protocol, and has the authority to apply certain measures to countries that are not fulfilling their obligations. In the case of noncompliance, sanctions are envisaged, the most important of which is a ban on participation in the mechanisms of flexibility of the Protocol. The Implementation Committee of the Protocol can mobilize financial

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and technical resources to help those countries that have difficulties in meeting their commitments. The supreme body of the Protocol is the Meeting of the Parties. 6.2.3. Marrakech Accords. Verification at the international level At the 7th Conference of the Parties to the Convention, in Marrakech, Morocco, in 2001, by-laws, regulations and rules for the implementation of the provisions of the Kyoto Protocol were developed and unanimously agreed. They should be adopted at the first conference of the countries participating in the Kyoto Protocol after its entry into force. The adoption of these agreements paves the way for the launch of large-scale practical actions to reduce greenhouse gas emissions. The adopted package of agreements establishes all the requirements that are necessary to participate in the mechanisms of flexibility under the Kyoto Protocol, as well as the principles and rules for their application. According to the requirements of the Kyoto Protocol, all national communications and annual national inventories undergo an in-depth verification procedure for compliance with the UNFCCC and IPCC Guidelines, organized by the UNFCCC Secretariat. A group of experts is sent to the country to get acquainted with the primary data and the processing process, verify the correctness of the principles of inventory and use of the methodology. After this, the group draws up an official report, which is agreed with the government of the country being audited. The reports are published on the UNFCCC website www. unfccc.int. Questions for self-checking: 1. Tell about the conclusions of the world’ experts about the global warming and measures for its reduction. 2. Explain the term “the concept of sustainable development”. 3. List the most important documents of the concept of sustainable development.

Chapter 6. Concept of sustainable development 4. Describe the United Nations Framework Convention on Climate Change. 5. Describe the United Nations Conference on Environment and Development, held in 1992 in Rio de Janeiro (CED-92). 6. Describe the World Summit on Sustainable Development, held in 2002 in Johannesburg (WSSD-2002). 7. Tell about the Kyoto Protocol to the UN Framework Convention. 8. Describe Marrakech Accords.

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Chapter 7

ECOLOGICAL CHARACTERISTIC OF OIL AND GAS EXTRACTION AND OIL PROCESSING PRODUCTIONS

Exploration, drilling and development of oil fields should be carried out in full and strictest compliance with the measures on the protection of mineral resources and the environment (Fig. 13).

Figure 13. Oil spills on the soil on the oil field

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Chapter 7. Ecological characteristic of oil and gas extraction and oil ...

Environmental protection includes measures aimed at ensuring safety of human settlements, rational use of land and water, prevention of pollution of surface and groundwater, air basin, preservation of forest areas, nature reserves, protected zones, etc. Subsoil protection envisages a complex of measures aimed at preventing loss of oil in the ground due to the low quality of sinking wells, violations of the technology of development of oil deposits and operation of wells, leading to premature flooding or layer degassing, fluid exchange between the productive and the adjacent horizons, destruction of oil-containing rocks, upsetting columns and cement behind them. By the level of negative effects on the environment oil and gas industry occupies the first place among the industries. It pollutes almost all spheres of the environment – the atmosphere, hydrosphere, and not only the surface but also groundwater. The first characteristic feature of the oil and gas production is a high danger of its products. These products have a fire hazard for all living organisms and are dangerous by their chemical composition, hydrophobicity, possibility in high-pressure streams of gas to diffuse through the skin into the body by high-pressure jets of abrasiveness. Gas mixing with air in certain proportions forms explosive mixtures. The second feature of the oil and gas production is that it can cause a profound transformation of natural objects of the Earth’s crust at great depths – up to 10 – 12 ths. meters. The process of oil and gas production is accompanied by the extensive and very significant impact on the reservoirs (oil, gas, aquifers, etc.). Thus, the intense extraction of oil on a large scale from the highly porous sand reservoirs results in a significant reduction in formation pressure, i.e. pressure of reservoir fluid – oil, gas and water. Reduction in the reservoir pressure causes a redistribution of load – the pressure on the pore walls reduces and hence the pressure in the rock skeleton formation rises. These processes reach such a large scale that can lead to earthquakes. Oil & gas production can affect not only the deep structures in an individual layer, but also several different by depth layers simultaneously. The balance of the lithosphere is distorted, i.e., the geological

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environment is disturbed. The modern technology of fastening wells during the drilling process is imperfect and does not provide a reliable isolation of formations behind the casing string. The above mentioned processes have led to contamination of drinking water in those areas where oil and gas are extracted. Inhabitants in many localities are compelled to use the drinking water from the other regions. The third feature of the oil and gas production is that almost all of its objects, applied materials, equipment and technology are the source of increased danger. This includes all transport and special machines. Pipelines with liquids and gases under high pressure, all the power lines are dangerous, many chemicals and materials are toxic. Toxic gases can come from the wells and the same toxic gases such as, for example, hydrogen sulphide, can be separated from the solution. Environmentally hazardous are the torches, in which the unused by-product gas is burned. The system of collection and transport of oil and gas must be sufficiently hermetic. The accidents on these objects lead to severe environmental consequences. The fourth feature of oil and gas production is that for its objects it is necessary to withdraw the land areas from the agricultural, forestry or other use. In other words, the oil and gas industry requires the removal of large areas of land (often in the highly productive lands). The objects of oil and gas occupy a relatively small area in comparison with, for example, coal mines, occupying a very large area (careers and overburden). However, the number of objects of oil and gas is very large. Due to a very large dispersion of oil and gas production, its objects need a distributed network for communications. The total area of land allocated under the oil and gas production – the arable lands, forests, hayfields, pastures, reindeer moss, etc. is quite large. The fifth feature of the oil and gas production is a huge number of vehicles, particularly of automotive vehicles. All this technique somehow or other contaminates the environment: air – by exhaust gases, water and soil – by oil (diesel fuel and oil). Sources of contamination of water objects and the oil fields are presented in one way or another on any part of the technological scheme: from the well to the oil tanks of oil refineries.

Chapter 7. Ecological characteristic of oil and gas extraction and oil ...

The main pollutants of the environment in the technological processes of oil production are: – oil and oil products; – sulfur and hydrogen sulfide gases; – saline reservoirs and waste waters of the oil fields and drilling of wells; – drilling sludge; – oil, water and chemicals used to intensify the processes of oil extraction, drilling and oil treatment, gas and water. By the spatial feature the pollution sources are divided into: – the point sources (wells, pits); – linear (pipes, water lines); – area (oil fields, field). Depending on the duration they are divided into systematic and temporary sources of pollution. The level of pollution of the environment by the waste production is estimated by the multiplicity of excesses of the maximum permissible (allowable) concentration (MPC or MAC) of substances entering the natural objects. The biggest part of hydrocarbon pollution, 75%, goes to the atmosphere, 20% to the surface and ground waters, and 5% – to the soil. Environmental pollutants at the drilling of wells and equipment are numerous chemical reagents which are used for the preparation of drilling fluids. During the construction of the drilling site, pollution of the atmosphere is mainly limited to atmospheric emissions of exhaust gases from the engines of vehicles. In the period of penetration of wells, the adverse effects on soil, surface and groundwater have drilling fluids. During well testing the hydrocarbon pollution is predominant, and at the stage of dismantling of the drilling equipment, the contamination of the territory occurs because of using of exhaust technical materials and equipment which cannot be recovered. The sources of pollution during drilling can be divided into permanent and temporary. The first group includes filtering and leakage of liquid wastes of drilling from the sludge pits. The second group – violation of tightness of the cemented area behind columns and the

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casing leading to manifestations and inter-sheeting overflows; absorption of boring solution during drilling; emissions of formation fluid on a day surface; boring flood watersor from melting snow and spills, in this case with its content. Intensive long-term exploration and exploitation of oil fields causes crustal deformation, accompanied by vertical and horizontal displacements of rocks. An essential contribution to air pollution gives petroleum gas burnt in torches every year in the amount of tens of billions of cubic meters. Air protection in the oil industry is mainly directed against the loss of oil by reducing its evaporation during its gathering, transportation, preparation and storage. Questions for self-checking: 1. Explain the term “environmental protection”. 2. What is “subsoil protection”? 3. Describe the features of negative effects on the environment caused by exploration, drilling and development of oil fields. 4. List the characteristic features of the oil and gas exploration, drilling and production. 5. Tell about the types of the pollution sources during oil and gas production.

Chapter 8

SOURCES OF ENVIRONMENTAL IMPACT OF OIL COMPONENTS FROM OIL PRODUCTION AND REFINERIES

All technical power of modern civilization is based on the use of energy, which is based on the removal of oxygen from the air. All technologies for obtaining energy by oxidation destroy the Earth’s atmosphere, irreversibly bind atmospheric oxygen to water. Burning of 1 kg of gasoline absorbs 3.5 kg of oxygen from the air. Combustion of natural gas produced per year absorbs more than 11 billion tons of oxygen from the atmosphere. It is no accident that only 17% of oxygen is contained in the air of megacities, instead of natural 21%. Drilling rigs, oil and gas fields are technological objects that release various pollutants into the atmosphere. Contamination of the atmosphere during testing of productive horizons can be quite intense despite their short-term period. The amount of flared oil and associated gas depends on the flow rate of fluids and may be hundreds of tons by weight. The combustion process itself can take several weeks. During drilling of wells, the main sources of air emissions are diesel plants. When drilling wells, the sources of atmospheric pollution are: – volley emissions from oil and gas occurrences; – combustion of hydrocarbons in flare units; – cleaning of the bottomhole formation zone; – thermal detoxification of drilling sludge; 125

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– long tests of drilled wells, diesel drives and boiler installations on drilling rigs. Every year, for example, in Russia, in the areas of oil and gas production, one uncontrolled release per 1,000 wells occurs. In case of accidental oil spills, atmospheric pollution occurs due to evaporation of low-molecular hydrocarbons. At all oil refineries there are considerable emissions of hydrocarbons in the atmosphere. This evaporation of oil and oil products takes place from open surfaces of treatment facilities. There are the leaks of liquids and vapors coming from pumps and compressors. Usually safety valves dump gases on a torch, but at an overload of a gas torch it is dumped in the atmosphere. Reverse waters from ablation and evaporation from coolers also pollute the atmosphere. Sources of environmental pollution from petrochemical productions are conditionally subdivided into envisaged and unorganized (casual). Organized pollutions are caused by investigation, drilling, production, transportation, processing of primary and secondary oil refining. Unorganized pollutions are caused by leakage of oil and oil products due to leakage of equipment, emergency emissions, accidents during transportation, oil spills during fountains from wells, seepage of hydrocarbons through soil into reservoirs and other unforeseen circumstances that may also arise during drilling, production, pumping oil at pumping stations, operation of processing, oil-loading and pipeline transport equipment, etc. Among the organized sources of pollution from the primary processes of oil processing, the most environmentally significant are the processes of desalting and dehydration of oil in the electrical desalting plants (EDP), separation and rectification separation of petroleum associated gas, direct distillation of oil, stabilization of oil emulsions with the use of surfactants. The largest contribution to the environmental pollution is made by the organized sources from secondary processes of oil and petroleum products processing: vacuum distillation, thermal cracking (py-

Chapter 8. Sources of environmental impact of oil components. ...

rolysis, vapor phase and liquid phase cracking), catalytic cracking, reforming, hydrocracking, hydrodesulfurization, visbreaking, coking, bitumen production, alkylation, isomerization, as well as processes of basic organic synthesis and polymerization. A large share of the contribution to the overall pollution of the environment belongs to the processes of deep processing of oil and waste of oil production – vacuum distillates from the processing of fuel oil, tar, oil sludge, barn oil; heavy residues of hydrocracking, reforming, visbreaking, dewaxing, deasphalting, etc. More than 70% of gasoline is produced by catalytic cracking of petroleum distillates obtained from pre-processed oil waste. The processes of deep oil processing are considered to be the most environmentally harmful production, since they are associated with air emissions of carcinogenic polynuclear hydrocarbons of aromatic series, olefins, acetylenes and other hydrocarbons (CnHm), greenhouseforming (CO2, CO, NOx) and acid-forming (SO2, H2S) gases. In the upper atmosphere they are involved in chain processes that lead to the formation of smogs, acid precipitation, contribute to the destruction of the ozone layer and the penetration of UV radiation that causes a “greenhouse effect”. It is proved that the main contribution to global warming of the Earth as a result of the “greenhouse effect” is made not so much by carbon dioxide but by nitrogen oxides (nitrous oxide, N2O). Nitrogen makes up 78.084% of air and is contained in oil, mainly in heavy fractions, up to 1.3% in the form of porphyrin complexes, nitrogen bases, amines, pyrrolidones, pyridines and other organic derivatives. In the course of burning of fuel oil and boiler fuels on the basis of oil and oil products in the presence of air, not only CO2, CO, SO2, H2S, CnHm are released to the atmosphere, but also a large amount of nitrogen oxides (NOx), among which there is a high amount of N2O nitrous oxide, steady in air and able to collect in an upper atmosphere and then enter chain interactions. According to forecasts of specialists, over the past 100 years, the CO2 content in the atmosphere has increased by 10%, with the bulk of 360 billion tons formed as a result of fuel combustion and if the rate

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of growth of fuel combustion continues, in the next 20-30 years, the amount of CO2 in the atmosphere will double and can lead to global climate change. During the drilling of wells, the main sources of air emissions are diesel installations. A powerful source of environmental pollution by oil and oil products is the storage and transportation system involving rail, pipeline and sea transport. Railway transportation is carried out in special tanks – containers and tank wagons intended for storage and transportation of oil, which are equipped with safety-release and safety-inlet (vacuum) valves of the pontoon type. Depending on the external conditions (temperature, pressure), mode of transportation (shaking, mixing), they are able to release accumulated condensed gaseous hydrocarbons into the atmosphere during the day, and let in air at night when cooled. The release is carried out in the mode of “day breathing” and “night breathing”. This causes serious damage to the environment in the territories along the transport routes of oil transportation. There is also a likelihood of occurrence of emergency situation on the railways leading to oil spillage and, as a result, soil contamination, as well as of land-based and underground water sources. A threat to the environmental safety is caused by pipeline transportation, the length of which reaches several hundreds and thousands of kilometers. Temperature and pressure changes, corrosion and clogging of pipes, oil pump stations, oil pipeline junctions, breach of integrity of pipeline joints can lead to accidental oil spills and pollution of soils, their entry into the air by evaporation and into water bodies. The large length of oil pipelines contributes to the spread of pollution in large areas, which should be taken into account when arranging the transportation system for oil and oil products. As a result of oil bottling from ground transportation systems, uncontrolled release of hydrocarbons into the atmosphere, entry of heavy metals contained in the oils into the soil and water sources occurs. Since oil and products based on it are the most important energy carriers and the demand for them is expected to last for the next 2530 years, the problem of water basin pollution remains very important.

Chapter 8. Sources of environmental impact of oil components. ...

One of the main types of pollution is hydrocarbon contamination of the Earth’s water basin. In recent years, serious concern has been caused by the pollution of the oceans by oil as a result of the crash of tankers and oil emissions in boreholes located in the high seas. By estimates of experts from various sources as a result of activity of people from 5 to 10 million ton of oil get to the ocean (Fig. 14). As 1 g of oil, spreading on the surface of the ocean, occupies the space of 12 km, the World Ocean probably is covered for a long time with a thin superficial film of hydrocarbons.

Figure 14. Oil spills into the ocean. Oil pollution of the marine area

A big share of pollution is the share of oil transportation (tab. 13) as the main oil-extracting areas are located at a considerable distance from the areas of its consumption and processing. A part of this oil (up to 0.5%) is thrown out to the ocean as there is a practice of dumping of wash and ballast waters into the high sea that leads to serious pollution. Then empty tankers are filled with sea water which serves as the stabilizing ballast on their way back. Sea water forms an emulsion with oil products left in tankers. Water contaminated with oil is subsequently discharged in high sea areas, specifically stipulated by international agreements, but often these operations are carried out near the coast in violation of the existing laws. Many areas of the Mediterranean, as well as the English Channel and

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the North Sea are systematically polluted by such illegal discharge of ballast water by tankers. Table 13 Distribution of the contribution of various sources to the oil pollution of the World Ocean No 1

Source of pollution

Transportations (total) Usual transportations Catastrophe 2 Removal by rivers 3 Contact from the atmosphere 4 Natural sourses 5 Industrial waste 6 City waste 7 Waste from coastal oil refineries 8 Extraction of oil on the high seas: Conventional operations Marine accidents TOTAL

Total amount, Share, % million tons/year 2.13 34.9 1.83 30.0 0.3 4.9 1.9 31.1 0.6 9.8 0.6 9.8 0.3 4.9 0.3 4.9 0.2 3.3 0.08 1.3 0.02 0.3 0.06 1.0 6.11 100

About a half of losses of oil when transporting is the share of loading of ballast and cleaning of tankers. Though 80% of the world tanker fleet use the system of control actions of Liquid off Take System (LOT) for reduction of the amount of the oil products getting to the sea in the course of release from ballast, more than 70% of pollution of the sea are the share of 20% of the tankers which do not apply the LOT system. In the LOT system water and oil products are used as ballast. Less dense oil products settle down in the top part of tanks, and rather clean sea water discharges from the lower part to the sea. The oil products mixed with a small amount of sea water remain in tanks and then are overloaded to the next tanker at its filling except for some special cases when oil doesn’t contain admixture of sea water. Transportation of oil and petroleum products contributes to the pollution of water bodies in approximately the same scale as rivers

Chapter 8. Sources of environmental impact of oil components. ...

and urban drains. A significant share of oil hydrocarbons is deposited in the areas of large cities, getting here from different sources. These include heating systems that run on oil, car maintenance operations, landfills of expended lubricants, cooling emulsions, etc. Precipitation contributes to the washing out of contaminants in the drainage structures and then into the water. As light gasoline penetrates into the soil 7 times faster, than water, it gives unpleasant taste to drinking water even at such low concentration as 1 million-1. Besides, in the presence of oil hydrocarbons the toxicity of other pollutants, in particular metals and the chlorinated hydrocarbons, is more pronounced. It has been established that during deepening works on the bottom, part of the petroleum hydrocarbons passes from the bottom sediments into the water column in the form of emulsion particles or in a dissolved form, and their further fate largely depends on the initial state when entering the water. In water, petroleum products can be subjected to one of the following processes: 1) assimilation by marine organisms; 2) re-sedimentation; 3) emulsification; 4) the formation of oil aggregates; 5) oxidation; 6) dissolution and evaporation. A specific feature of oil pollution is the ability to capture and concentrate other contaminants, for example, heavy metals and pesticides. When the oil spreads over a large area, the probability of various reactions greatly increases, since substances soluble in oil participate in a variety of chemical processes. In light fractions of oil products of gasoline and kerosene, the surface tension at the boundary with water is higher and the spreading rate on the surface is lower than for petroleum products containing heavy fractions, such as fuel oil and oil. In this regard, petroleum products from light fractions (with the same amount) spread on a smaller surface area of the water.

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Spreading of oil pollution occurs mainly under the influence of the following factors: flow, wind and water level fluctuations, and has its own peculiarities. It has been established that one drop of oil forms a spot on the surface of the reservoir with an area of approximately 0.25 m2, and 1 ton of oil covers an area of about 500 hectares of the surface of the reservoir. Bottom sediments, adsorbing hydrocarbons, on the one hand, lead to a decrease in their content in water, and on the other, can serve as a source of repeated water pollution. Hydrocarbons as a result of adsorption on suspended particles settle to the bottom, and not always remain on the surface of the bottom sediments. Complex physical, chemical and biological processes occurring at the interface between water – dense bottom sediments or near it, can change the physical and chemical state of hydrocarbons. In addition, the hydrocarbons associated with the suspended particles can be recycled to the water column and recycled in successive stages of release, oxidation and precipitation. Observations in various regions of the Caspian (western coasts of the Middle and Southern Caspian), the Baltic (Riga Gulf), and the White Seas (Onega and Dvina Gulfs) have made it possible to establish high concentrations of oil hydrocarbons corresponding to the zones of the greatest sedimentation and low concentrations in the zones with active hydrodynamic regime. The most oil-polluted areas were the bottom sediments of the investigated areas of the Caspian Sea, and the least – the Baltic and White Seas, which is due to the uneven volume of hydrocarbons entering them. The low density of modern sediments and hydrodynamic activity contribute to the pollution of bottom sediments in depth. At the same time, in the presence of oil, binding of non-condensed sands and silt increases, dispersion and porosity, because of which some part of ground deposits will be transformed to a layer with the high content of oil hydrocarbons, decrease. There is a significant correlation between the granulometric composition of bottom sediments and the content of hydrocarbons in them (tab. 14). In case of a disturbance in the structure of bottom sediments

Chapter 8. Sources of environmental impact of oil components. ...

or other effects, the sorption values of each of the granulometric types can vary significantly under the influence of hydrometeorological factors (sea disturbance, flow), deepening the bottom and hydraulic engineering works. It is well known that oil, mixing with water, forms emulsions of two types: “oil in water” and “water in oil”. Emulsions “oil in water”, made up of oil droplets up to 0.5 microns in diameter, are less stable and are especially characteristic of oil-containing surfactants. After the removal of volatile and soluble fractions, the residual oil often forms viscous back emulsions that are stabilized by high-molecular compounds such as resins and asphaltenes and contain 50-80% of water – “chocolate mousse”. Under the influence of abiotic processes, its viscosity rises, and its coalescence into aggregates-oil clusters from 1 mm to 10 cm in size begins. The aggregates are a mixture of highmolecular hydrocarbons, resins and asphaltenes. The loss of oil on formation of aggregates is 5-10%. High-viscosity structured formations in the form of oil lumps can be thrown out for a long time by currents to the shore and settle to the bottom. Oil lumps are often populated with periphyton (blue-green and diatom algae, barnacles and other invertebrates). Hydrocarbon content in various types of bottom sediments No Type of sedimentary deposits at Average contents the bottom of hydrocarbons, mg/g of dry soil 1 Clay silt 6.6 2 Loamy silt 1.5 3 Sandy silt 0.9 4 Coarse sand 0.2 5 Medium sand 0.7 6 Fine sand 2.2 7 Dusty sand 6.4

Table 14

Range of fluctuations in hydrocarbon content, mg/g dry ground 1.0-17.1 0.5-2.0 0.3-2.2 0.1-0.2 0.1-0.7 3.8-8.9

The ratio of all processes promoting removal of oil hydrocarbons from the water environment was studied poorly. It is established that the activity of bacteria defines the final fate of oil in water.

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Some of the fractions contained in oil are highly toxic, and their toxicity increases as the concentration of these fractions increases when they are absorbed or dissolved in the aqueous system. Low boiling saturated hydrocarbons and some aromatic compounds (benzene and xylene) are toxic, but they are to varying degrees soluble in water. High-boiling fractions include carcinogenic substances represented by aromatic polycyclic compounds. Oil itself is also toxic, but there is little data on poisoning by oil entering the body. Oil is emulsified, emulsions with different contents of oil are toxic and can physically affect organisms, causing suffocation. The overall impact of petroleum products on the marine environment can be divided into five categories: – direct poisoning with a lethal outcome; – serious impairment of physiological activity; – the effect of direct envelopment of a living organism with oil products; – painful changes caused by penetration of hydrocarbons into the body; – changes in the biological characteristics of the habitat; – lethal poisoning is possible as a result of direct influence of hydrocarbons on some important processes in cells, especially on the processes of metabolism. Soluble aromatic hydrocarbons in water constitute the greatest danger to the marine environment. The influence of paraffin hydrocarbons of low molecular weight (C10 and less) can cause narcotic action, but the concentration necessary for this purpose is extremely high and is absent in oil slicks. The available data indicate that death of adult marine organisms can come after the contact within several hours with soluble aromatic hydrocarbons which content is 10-4-10-2%. The lethal concentrations of such components for roe and fry are lower and equal to 10-5%. Thus, roe and fry are 10-100 times more sensitive to the action of hydrocarbons than adult organisms. Lethal concentrations of aromatic hydrocarbons are possible in oil stains that have not yet been exposed to atmospheric effects, but after a long stay in water, oil loses many volatile and soluble components.

Chapter 8. Sources of environmental impact of oil components. ... Questions for self-checking: 1. What sources of environmental pollution by oil and oil products are classified as organized? 2 . What sources of environmental pollution by oil and oil products are classified as unorganized? 3. What primary processes of refining (processes of separation) are the most environmentally significant? 4. Which secondary refining processes are the most environmentally significant? 5. What is the environmental impact of the processes of deep processing of oil and petroleum wastes? 6. What is the contribution to the environmental pollution from rail transport of oil and oil products? 7. What is the contribution to the environmental pollution from pipeline transportation of oil and oil products? 8. What is the contribution to the environmental pollution from the sea transportation of oil and oil products? 9. What is the scale of pollution of the oceans with oil? 10. What is the impact of petroleum in seawater on humans and animals?

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Chapter 9

OIL AND GAS PROCESSING ENTERPRISES OF THE REPUBLIC OF KAZAKHSTAN – SOURCES OF HARMFUL EMISSIONS

The oil industry of Kazakhstan is one of the main branches of Kazakhstan’s economy. About 200 oil and gas fields are located on the territory of Kazakhstan (Fig. 15). The total amount of reserves is estimated at 11-12 billion tons. Almost 70% of these resources are located in the western regions of Kazakhstan. The Russian military, travelers and scientists noted the high probability of finding industrial oil reserves in this region. The first Kazakh oil was mined in November 1899 at the Karashungul deposit, in the Atyrau region. Further in the Emba area two deposits of high-quality oil – Dossor (since 1911) and Makat (since 1915) were discovered and developed. The geological conditions of the sedimentary basins of Kazakhstan favor the expansion of the resource base of the oil and gas industry. Kazakhstan by the volume of proven oil reserves occupies the 12-th place in the world. The country is a leading exporter of oil among the CIS countries. Nowday more than 3/5 of the country is occupied by oil and gas fields, and more than two hundred fields are known. Export of petroleum from Kazakhstan is one of important factors of expansion of world economic communications, inclusion of the country in the globalization processes, realization of not only economic interests. 136

Chapter 9. Oil and gas processing enterprises of the Republic of Kazakhstan ...

Figure 15. A map of the main oil and gas fields in Kazakstan

9.1. Oil and gas fields in Kazakhstan

The largest oil fields of Kazakhstan are Kashagan, Tengiz, Karachaganak and Kashagan (location – the north of the Caspian Sea) with the geological reserves, estimated as 4.8 billion tons of oil. Tengiz field (location – Western Kazakhstan) is one of the world’s deepest producing super giant fields. The Karachaganak field’s oil and liquid condensates are estimated at approx. 1.2 bln. tons. Let’s consider the largest oil fields in Kazakhstan. 1. Kashagan East and West Kashagan is a super-gigantic oil and gas field in Kazakhstan, located in the north of the Caspian Sea. It was opened on June 30, 2000. It is one of the largest deposits in the world, discovered over the past 40 years, as well as the largest oil field at sea. The deposit was discovered in the year of the celebration of the 150th anniversary of the famous Mangystau poet-zhyrau of the XIX century – Kashagan Kurzhinuly. The word “�������������������������������������������� қашаған������������������������������������� ” in translation from the Kazakh language means a character trait – “restive, strong-willed, elusive” (more often used about an animal).

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Stocks Geological stocks of Kashagan are estimated at 6.4 billion tons of oil. In Kashagan there are large reserves of natural gas more than 1 trillion m3. Oil production in Kashagan, according to ENI calculations, in 2019 should reach 75 million tons per year. With Kashagan, Kazakhstan will enter the Top-5 world’s oil producers. Project participants Partner companies for the Kashagan project: Eni, KMG Kashagan B.V. (a subsidiary of Kazmunaigas), Total, ExxonMobil, Royal Dutch Shell have 16.81% stake, ConocoPhillips – 8.4%, Inpex – 7.56%. They are part of the joint operating company North Caspian Operating Company (NCOC). 2. Tengiz Tengiz (Kazakh Teңіз, English Tengiz) is a giant oil and gas field in the Atyrau region of Kazakhstan, 160 km south-east from Atyrau. It refers to the Caspian oil and gas province. It was opened in 1979. April 6, 1991 was the beginning of industrial production at this field. Stocks The predicted volume of geological stocks is 3.1 billion tons of oil. Recoverable reserves of the field are estimated from 750 million to 1 billion 125 million tons of oil. Reserves of associated gas are estimated at 1.8 trillion m3. Project participants In 1993, the Government of Kazakhstan established JV Tengizchevroil LLP in cooperation with Chevron to develop the Tengiz oil field. Today the partners are already four companies: NC KazMunaiGas (20%), Chevron Overseas (50%), Exxon Mobil (25%) and LukArco (5%). 3. Uzen Uzen is an oil and gas field in the Mangistau region of Kazakhstan, on the Mangyshlak peninsula. It refers to South Mangystau oil and gas area. It was opened in 1961.

Chapter 9. Oil and gas processing enterprises of the Republic of Kazakhstan ...

Stocks Reserves of oil of 1.1 billion tons. The center of production – the town of Zhanaozen. The source of raw materials includes oil and gas fields “Uzen” and “Karamandybas”, gas-condensate fields “Tasbolat”, “The Western Tenge”, Aktas, “Youzhny of Zhetybay” and one gas field “East Uzen”. The general recoverable reserves are estimated at 191.6 million tons of oil. Project participants The operator of the deposit is JSC Exploration and Production of NC KazMunaiGaz. Oil production in 2008 amounted to 7 million barrels. The record level of oil production – 16.3 million tons was recorded in 1975, the minimum level – 2.7 million tons in 1994. 4. Karashyganak Karachaganak field (Karachaganak, Karashyganak, Қarashyғanaқ in Kazakh, Karachaganak in English) – Kazakhstan’s oil and gas field, located in the West Kazakhstan region, near the town of Aksai. It was opened in 1979. Stocks Initial field reserves made over 1 billion tons of oil and gas condensate. From the Karachaganak field a part of the extracted gas is delivered by the condensate drain line to Orenburg (for processing at the Orenburg gas processing plant). Project participants Currently, the field under the production sharing agreement is being developed by an international consortium of British Gas and Eni (32.5% each), ChevronTexaco (20%) and Lukoil (15%). To implement the Karachaganak project, these companies merged into a consortium Karachaganak Petroleum Operating BV. It is planned that KPO will manage the project until 2038. 5. Kalamkas Kalamkas is a gas and oil field in the Mangistau region of Kazakhstan, on the Buzachi peninsula. It refers to the North Buzashins-

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koy petroleum region. It was opened in 1976. The development began in 1979. Stocks Geological reserves of oil are equal to 510 million tons, the total geological reserves of oil are 1,000 million tons. The projected oil production should be from 3 to 15 million tons per year. Project participants The operator of the Kalamkas Severny deposit is JSC KazMunaiGas Exploration and Production. Currently, the development of the deposit is conducted by OJSC Mangistaumunaigas. 6. Zhanazhol Zhanazhol is a gas condensate field in the Mugalzhar district of the Aktyubinsk region of Kazakhstan. It refers to the Caspian oil and gas province. It was opened in 1978. Stocks Geological reserves of oil are estimated at 500 million tons. The Zhanazhol field has been under development since 1983, recoverable reserves have been estimated at more than 100 million m3 of oil, about a third of them have already been mined. In addition, the field contains 133 billion m3 of gas. Project participants Zhanazhol is being developed by CNPC-Aktobemunaigas, a Kazakh-Chinese joint venture. 7. Zhetybai Zhetybai is a gas-condensate-oil field in Mangistau region of Kazakhstan, on the Mangyshlak peninsula. It refers to South Mangystau oil and gas area. It was opened in 1961. Stocks Geological reserves of oil are 330 million tons, residual oil reserves are 68 million tons.

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Project participants Currently, the development of the field is being conducted by the oil company OJSC Mangistaumunaigas and its Jetybaymunaigas PU. 8. Aktoty Aktoty (Kazakh Aқtoty, English Aktote) is an offshore oil field in Kazakhstan. It is located 200 km to the south-east from the city of Atyrau. It was opened on September 2, 2003. Stocks Geological reserves amount to 269 million tons of oil, recoverable – 100 million tons. Project participants Currently, the deposit is included in the contract area of the North Caspian Operating Company (NCOC) consortium, which is developing the structures of Kashagan. 9. Kalamkas Sea Kalamkas Sea, in Kazakh Қаламқас-теңіз, англ. Kalamkas “A” offshore is a marine oil field in Kazakhstan. Located 150 km north-west from the Buzachi Peninsula. It was opened on September 3, 2002. Stocks Geological reserves are 156 million tons of oil, recoverable are 57 million tons. Project participants Currently, the deposit is included in the contract area of the North Caspian Operating Company (NCOC) consortium, which is developing the structures of Kashagan. 10. Kairan Kayran (Қaйрaн in Kazakh, Kairan in English) is an offshore oil field in Kazakhstan. It is located 150 km to the south-east from the city of Atyrau. It was opened on September 10, 2003.

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Stocks Geological reserves amount to 150 tons of oil, recoverable – 56 million tons. Project participants Currently, the deposit is included in the contract area of the North Caspian Operating Company (NCOC) consortium, which is developing the structures of Kashagan. 11. Kenkiyak Kenkiyak is an oil field in the Temir district of the Aktyubinsk region of Kazakhstan, 250 km south-west from Aktobe. It was opened in 1959. It refers to the East Emba oil and gas area. Stocks Geological reserves amount to 150 million tons of oil, the residual recoverable reserves of the field are estimated at 10.8 million tons of oil, the exploration block is estimated at 32.2 million tons of oil. Project participants The operator of the fields is the oil company CNPC-Aktyubemunaigaz. The most promising project for today is the development of the Karachaganak field, the total reserves of the field are 1.2 billion tons of oil and 1.35 trillion.m3 of gas. 9.2. Refineries of Kazakhstan

The first oil refining enterprise in Kazakhstan is the Atyrau refinery (Fig. 16). The construction of the plant started in 1943 under difficult wartime conditions, and in September 1945 the plant was put into operation. The technical design of the plant was developed by the American firm Badger and Sons, which supplied equipment for lendlease. The initial capacity of the plant on oil refining was 800 thousand

Chapter 9. Oil and gas processing enterprises of the Republic of Kazakhstan ...

tons per year and was based on oil of the Embinsky field and imported Baku distillate. From the very beginning the plant developed according to the fuel variant, with the production of aviation and automobile gasolines, various motor and boiler fuels. Today, Atyrau refinery is a large modern enterprise located in the oldest oil producing region of the country.

Figure 16. Atyrau refinery

Atyrau refinery is the only one, completely independent of Russian raw materials. It is connected by pipelines with the deposits of Mangyshlak and Tengiz. The Atyrau oil refinery processes heavy oil from fields of the Western region of Kazakhstan with the high content of paraffin. In the assortment of products there are gasolines, white spirit, diesel fuel, boiler fuel, fuel oil, coke. The Shymkent oil refinery was put into operation in 1985 and the design capacity of the plant on oil refining was 6 million tons per year (Fig. 17). In 1994 the enterprise named JSC “Shymkentnefteorgsintez” (ShNOS) was privatized, in 2000 it was acquired by the Canadian company Hurricane. In 2000 reconstruction of the section of hydrotreating of diesel fuel and kerosene was carried out.

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Currently, the management of PetroKazakhstan Oil Products LLP (hereinafter – PKOP) is carried out on a parity basis: the National Company KazMunayGas represented by JSC KazMunayGas – Refining and Marketing, and the China National Petroleum Corporation (CNPC). The processed raw materials of PKOP are mainly Kazakhstan oil from the Kumkol and Kenkiyak fields (oil mixture from the Kumkol field (80%), as well as West Siberian oil (20%). Oil comes from Western Siberia through the Tyumen-Omsk-Pavlodar-Shymkent pipeline. Oil is low-sulfur, one of the best in quality among the CIS countries. The depth of oil refining is 60.4%. The plant produces 30% of the total current volume of petroleum products produced by three refineries in Kazakhstan. The assortment of petroleum products includes various grades of gasoline, diesel fuel, aviation kerosene, liquefied gas, vacuum gas oil and fuel oil. The products of PetroKazakhstan are of high quality due to the application of a professional and high-tech refining process and the exceptionally high quality of Kumkol oil. Shymkent Oil Refinery (LLP PetroKazakhstan Oil Products) in 2016, with a plan of 4, 444, 623 tons, actually processed 4, 501, 467 tons of oil, the execution of the plan was 101.28%.

Figure 17. Shymkent Oil Refinery

Chapter 9. Oil and gas processing enterprises of the Republic of Kazakhstan ...

The Shymkent oil refinery is the only oil refinery located in the south of Kazakhstan in the most densely populated part of the republic. Taking into account a favorable geographical location and high technical capabilities the enterprise has all prerequisites for implementation of deliveries to the internal and external markets. The design capacity of the Shymkent oil refinery is 5.25 million tons, or about 40.65 million barrels of oil a year. The Development Bank of Kazakhstan JSC (a subsidiary of Baiterek Holding) has opened a credit line for financing the modernization and reconstruction project of the Shymkent oil refinery of PetroKazakhstan Oil Products LLP. The total amount of loan for a term of up to 13 years is 932 million US dollars. The $1.9 billion project is funded under the State Program for Industrial and Innovative Development of the Republic of Kazakhstan for 2015-2019. Modernization and reconstruction of the Shymkent oil refinery was planned to be realized in two stages: at the first stage it was planned to launch the production of gasoline and diesel fuel of ecological classes in K4 and K5 (analogous to Euro-4 and Euro-5) adopted in the countries of the Customs Union; in the second stage, it was planned to increase the depth, as well as oil refining capacity up to 6 million tons from 5.250 million tons per year. The Pavlodar petrochemical plant (Fig. 18) was put into operation in 1978. In 1978-1994, it was called the Pavlodar Oil Refinery (POR), since 2009, JSC “POR” was included in the group of companies of the JSC National Company KazMunayGas, since March 2013 it is LLP “Pavlodar Petrochemical Plant”. The owner of the oil refinery is JSC National Company KazMunayGas. Pavlodar refinery is one of the best plants in terms of the ratio of primary (separation) and secondary (conversion) processes. The plant is one of the most modern in technology in the Republic of Kazakhstan. The plant processes oil into different types of fuel and provides a processing depth of up to 77-85%, which corresponds to the level of the best producers of petroleum products. According to the

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technology, the plant is oriented on processing West Siberian oil. Oil for processing at the plant comes from Western Siberia through the Omsk-Pavlodar pipeline. The plant produces only unleaded gasoline, fuel for jet engines, summer and winter diesel fuel, boiler fuel, fuel oil, bitumen, petroleum coke, liquefied gases.

a

b Figure 18. Pavlodar refinery (petrochemical plant)

Chapter 9. Oil and gas processing enterprises of the Republic of Kazakhstan ...

A distinctive feature of oil products produced in Kazakhstan is low quality and maximum load on the environment. At the refineries in Kazakhstan, only the line of atmospheric distillation, reforming straight-run gasoline and hydrotreatment of diesel fuel operate. At such a scheme of production it is not necessary to speak about complex processing, associated fat dry gases are burned in torches or in the best case in boilers. All this leads to formation of emissions of pollutants of waste of oil processing, their entry into the atmosphere, reservoirs, and oiling of soils. 9.3. Kazakhstan Gas Processing Plants

The main area of natural gas production is Aktobe, Atyrau, West Kazakhstan, Kyzylorda and Mangystau regions.    Most of all natural gas (about 60%) and condensate (about 80%) reserves are contained in the Karachaganak field – 1.2 billion tons of oil and condensate, 1.35 trillion. m3 of natural gas. The gas contains 57% of methane, 9% of ethane, 20% of hydrogen sulfide, etc. The reserves of the Imashev gas field (Atyrau region on the border with the Astrakhan region of the Russian Federation) amount to 128 billion m3 of natural gas. Forecast reserves of the Aral Sea basin are 2 trillion m3 of natural gas, the Aryskum Basin is 100 billion m3 of gas, Kumkol is 100 billion m3 of natural gas and 180 million m3 of by-product gas. The total reserves of the gas condensate fields of South Zhetybai, West Tengiz, East Uzen are 55 billion m3 of natural gas and 3 million tons of condensate. The reserves of the Amangeldy group of gas fields are 25 billion cubic meters of natural gas. The gas contains 63.2% of methane, 8.5% of ethane, 2% of propane, and others. Along with the refinery, Karachaganak and Mangistau oil and gas processing complexes operate on the territory of the republic. In Kazakhstan, there are also the gas processing plants (GPP). To date, the largest gas processing plants (GPP) in Kazakhstan are the Kazakh, Tengiz, Karachaganak and Zhanazholsky.

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Tengiz Gas Processing Plant (TGPP) Tengiz GPP is located in the Tengiz oil and gas field, the design capacity of the plant is 2.55 billion cubic meters of gas per year. It has two technological lines, the first was put into operation in 1991, the second in 1995. The associated gas from the Tengiz field is characterized by a high content of propane-butane fraction and hydrogen sulphide, the presence of carbon dioxide and associated components, which require purification and additional processing. It is assumed that after achieving full production capacity of the plant, about a third of the produced gas will be pumped back into the reservoir, and the remaining volumes will be used for production of commercial gas, propane, butane and sulfur. Kazakh Gas Processing Plant (KazGPP) The first phase was put into operation in 1973, the second in 1979. The factory is located in Zhana Ozen (Fig. 19). The Kazakh gas processing plant, located in Mangistau region, was built for the utilization of associated gas from the Mangyshlak fields and for providing the plastics plant with raw materials in Aktau. The raw materials are associated and natural gas from the deposits of Ozen and Zhetybai, as well as gas condensate produced by the Mangistau Gas Production Department. The plant’s capacity is 1.2 billion m3 per year.

Figure 19. Kazakh Gas Processing Plant (KazGPP)

Chapter 9. Oil and gas processing enterprises of the Republic of Kazakhstan ...

Zhanazhol Gas Processing Plant (ZHGPP) The Zhanazhol oil refinery (ZHGPP) was originally designed for processing 710 million cubic meters of gas per year. After the reconstruction of the plant, made by CNPC-Aktobemunaigas, its production capacity reached 800 million m3 gas per year. It has two technological lines that were put into operation in 1984. In September 2003, the second Zhanazhol gas processing plant with a capacity of 1.4 billion cubic meters of natural gas per year was put into operation, and in 2007 the first stage of the third Zhanazhol gas processing plant was commissioned. A significant event in the republic was the start-up to the full production capacity of the associated petroleum gas processing plant of Turgai Petroleum JSC in the Kumkol field (Kyzylorda region) in October 2009. The construction of the plant, in which the shareholders invested more than 13 billion tenge, allowed creating new jobs. The launch of the complex will lead to the improvement of the ecological situation in the region. It is equally important that the company took a worthy place among a number of enterprises that possess knowledge and technologies of gas utilization, and Kazakhstan specialists can work at the level of international standards. The gas plant at Kumkol has a high level of automation, modern software, providing the enterprise with the equipment of a leading engineering company and advanced technologies aimed at ensuring a high level of safety and labor protection. All this will allow it not only to produce associated gas, but also to produce high-quality products. When building the gas processing complex, the unique experience and knowledge of Exterran company, operating in 30 countries of the world, was used. In the future, when processing natural gas in Kazakhstan, in addition to the separation of ethane and liquefied gases, an important step towards deepening the integrated use of gas can be the extraction of helium. The importance of this inert gas in the national economy is extremely high. Since the only source of helium gas, and the resources of this product are not recoverable, its extraction from helium-bearing raw materials is vital. The extraction of helium from gas can be ef-

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fectively combined with the process of obtaining ethane and propanebutane fractions from it, since cryogenic equipment is used in these industries. In addition to the economic effect, this gives an additional benefit on technological specialization, especially if the complex includes such production as pyrolysis of ethane with low-temperature separation of gas into fractions. 9.4. Environmental issues in Kazakhstan associated with oil and gas production and processing

The annual increase in the production of hydrocarbon raw materials and its further processing raises serious concerns about the environmental situation in the republic. The explored deposits will inevitably be developed further, which will lead to an increase in the risk of accidents and major spills at sea. More dangerous is the development of the North Caspian fields, where annual production in the coming years will reach at least 50 million tons with forecast resources of 5-7 billion tons, and according to forecasts of specialists in the coming years, the resource potential of the republic will allow it to reach a production level of 100 million tons tons of oil. Increasing the pace of development of natural oil and gas fields contributes to an increase in the release of pollutants into the atmosphere (Fig. 20), the hydrosphere and the lithosphere of the earth. Therefore, monitoring of the state of the environment of oil and gas deposits is one of the priority tasks in the sphere of state environmental control and expertise. Interannual dynamics of registered pollutants in the Northern Caspian in the last 10 years was characterized by the following key figures for petroleum products: the average annual pollution from 1 to 4 MAC, the maximum content of 11 MAC. There is a tendency to increase in the content of oil and oil products in the sea, this is due to the intensive development of hydrocarbon resources in the basin of the Caspian Sea and the operation of existing

Chapter 9. Oil and gas processing enterprises of the Republic of Kazakhstan ...

offshore wells. In the Northern Caspian, pollution from oil development was insignificant up to recent years; this can be explained by a weak degree of prospecting and a special conservation regime in this part of the sea. The situation changed with the beginning of the development of the Tengiz field, and then with the discovery of the second giant, the Kashagan field. Changes have been made to the reserve the status of the Northern Caspian, which allows exploration and production of oil (Resolution No. 936 of the Council of Ministers of the Republic of Kazakhstan of September 23, 1993 and Government Decision No. 317 of March 14, 1998). However, exactly here the risk of pollution is maximum because of shallow water, high reservoir pressures, etc. In the Atyrau region resources more than 40 oil and gas fields including the unique Tengriz field are developed. In 2000 the largest East Kashagan oil and gas field located in 70 km to the southeast from Atyrau in a shallow zone of the sea was found. In 2001 the oil-and-gas content of the Kashagan West field was confirmed. In Mangistau region, more than 60 deposits have been explored, of which 27 are oil and gas deposites. Sites adjacent to existing and conserved oil fields, flooded old oil wells of the North and East coasts are especially prone to toxification by petroleum products and their derivatives due to the sea level rise and phenomena in which the coastal enterprises are subjected to underflooding and draining into the sea. To date, vast areas of oil fields are covered, as leprosy, with rusty spots – these are traces left by oil, which has thoroughly soaked the soil (Fig. 21). Currently, more than 20 deposits located in the Atyrau region are already exposed to the Caspian Sea. In Mangistau region there is a threat of flooding of 8 fields. All this creates a serious danger of oil pollution by oil products. There are more than 150 wells in the sea water (of which more than 100 in the Atyrau region), of which 120 productive wells are conserved, but not properly equipped to prevent oil spills into the marine environment. In winter, on the northern coast of the Mangistau region, during the descent of ice, the wellhead equipment of the canned and liquidated wells is destroyed. Due to the transgression of the Caspian

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Sea under the threat of flooding there are more than 40 oil fields, oil and gas fields among which the unique ones – Tengriz, Korolevskoe, Kalamkas, Karazhanbas.

Figure 20. Emissions of pollutants to the atmosphere as a result of operation of the oil refinery

Figure 21. Impact of production and oil refining on ecology of reservoirs

In the territory of the Mangystau and Atyrau regions there are about one thousand earth barns which aren’t provided with any iso-

Chapter 9. Oil and gas processing enterprises of the Republic of Kazakhstan ...

lation in which more than 100 thousand tons of oil are stored. The total area of oil-contaminated lands in the same areas is more than 700 hectares on which more than 200 thousand tons of oil are poured. From time to time there are emergency ruptures of oil pipelines with oil spill on a relief. About scales of accidents it is possible to judge by such figures – oil reserves in the dangerous region are estimated at 5 billion tons. Despite the existence of a huge source of raw materials, the petrochemical industry of Kazakhstan doesn’t use fully an opportunity for fuller loading of capacities of the available enterprises. One of the main problems of the oil industry is the prevalence of raw orientation and very poor development of closing stages of production. Over 80% of the total volume of products produced in the country does not have a closed technological cycle. The share of petrochemical and associated chemical industries operating on the consumer market is below 20%, whereas in the economically developed countries this figure reaches 50-60%. A strong destabilizing effect on the dynamics of economic processes is dominated by capital-, fund– and energy-intensive industries in the petrochemical industry in the absence of its own raw materials base. The remoteness of oil refineries from the oil-producing regions plays a negative role. The majority of oil refineries work on imported raw materials. Because of the high costs of its acquisition, most of the petrochemical products produced in Kazakhstan are unprofitable and uncompetitive not only in the external but also in the domestic market. Over 80% of the demand for petrochemical products is met through imports. Almost all enterprises of the republic’s petrochemical complex do not produce the main types of their products, such as polypropylene, polystyrene, chemical fibers, rubber products (including tires), lacquers, paints, resins, polymer composite materials, and consumer goods. In this regard, urgent measures should be taken to restore the existing and introduce modern oil production, subject to strict compliance with the environmental legislation of the Republic of Kazakhstan, timely control and expertise of the state of the environment in the industry.

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In order to improve oil refining and reduce harmful emissions into the atmosphere, Kazakhstan has set the task of modernizing existing oil refineries. The ultimate goal of modernization is to bring the quality to the standards of EURO-4 and EURO-5, and also generally improve the quality of gasoline and fuel. Naturally, modernization of the refinery can positively affect the environment: 1) emissions from the activities of the plants themselves will become less harmful; 2) the quality of gasoline will reduce the toxicity of exhaust gases from transport by half. The future of the oil and gas producing and oil refining industries in Kazakhstan is mainly related to the Kazakhstan sector of the Caspian Sea. Given the current global imbalance between the level of oil production and consumption, Kazakhstan has good potential to increase its oil production and, consequently, the export of hydrocarbon raw materials to the world markets every year. Oil and gas still have no real alternative, and, therefore, there remains a need to develop oil and gas and oil refining industries, to develop technology and technology based on modern standards, and also to preserve the priorities in training highly qualified specialists for these fields of science and technology. Questions for self-checking: 1. Tell about Kazakhstan reserves of oil and the features of Kazakhstan oil. 2. Compare crude oil of Kazakhstan with that of another countries. 3. Tell about Kazakhstan reserves of gas. What are the main fields? 4. Describe the history of discovery of Kazakhstan/s deposits. 5. List the main oil fields of the Republic of Kazakhstan. 6. List the main gas-bearing deposits of the Republic of Kazakhstan. 7. List the RK refineries. 8. Characterize the Kazakhstan refineries. 9. What gas processing plants work in Kazakhstan? 10. What is the influence of oil and gas fields on the ecological situation in the regions? 11. What types of petrochemical industries are predominant in the economy of Kazakhstan? 12. On the basis of which facts it is possible to judge about preferable orientation of petrochemical productions in Kazakhstan? 13. What measures are taken to improve the environmental situation in Kazakhstan? 14. Tell about the prospects for the development of oil and gas technology and petrochemistry in Kazakhstan.

Chapter 10

OIL GAS AS A SOURCE OF AIR POLLUTION. FLARE (TORCH) UNITS

Significant contribution to the pollution of the air basin is made by oil gas, which is annually burned in torches in the amount of tens of billions of cubic meters. In the photo of the Earth, made from a satellite at night, the oil and gas industries of Western Siberia, the Mexican and Persian Gulfs, the Caspian and North Seas are clearly visible, lit by burning torches. Combustion of associated gas in flares is direct contamination of the atmosphere. Burning torches pollute the atmosphere with sulphurous compounds, causing all vegetation to be completely destroyed in a radius of 250 m from torches, at a distance of 3 km the trees dry and discard leaves. In subsoil licenses, oil companies undertake to utilize up to 90% of associated gas. In reality, dozens of percent are utilized. Losses of oil gas in many countries are very significant, for example, these only in Russia make up more than 8% of the total world losses of this valuable hydrocarbon raw material. Utilization of oil gas resources, as a whole, does not exceed 75%, which is equivalent to a loss of 80 million tons of oil. Despite the fact that the maximum degree of use of oil gas resources in the old oil and gas producing regions of the Volga and Northern Caucasus reaches 90-96%, its negative impact on the biosphere in some cases is dominant among the existing sources of pollution. 155

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It is necessary to consider high migration activity of gaseous substances, which are fixed not only at a pollution source, but also at a considerable distance from it. The maximum aura of dispersion (up to 15 km) is characteristic of hydrocarbons, ammonia and carbon oxides; hydrogen sulfide migrates at a distance of 5-10 km, and nitrogen oxides and sulphurous anhydride are noted within 1 – 3 km from the pollution center. In addition to the chemical impact of gas combustion, thermal pollution of the atmosphere also occurs. At a distance of 4 km from the torch, signs of vegetation inhibition are observed, and in the radius of 50-100 m – a disturbance of the background vegetation cover. The level of contamination spread across the area during gas flaring (Fig. 22) depends on the rate and qualitative composition of the gas, its relative density, the time of year and the prevailing wind direction in the area of the field. Weak circulation in the ground layers of the atmosphere leads to the deposition of gas stream components on the surface of the soil and water bodies. In the new oil-producing regions there is a disproportion between the rates of extraction of hydrocarbon raw materials and the introduction of systems for collecting and processing associated gas. Thus, only in Western Siberia, more than 10 billion cubic meters of gas are flared annually in torches. At the same time, 7 million tons of toxic compounds enter the air basin.

Figure 22. General view of a flare unit

Chapter 10. Oil gas as a source of air pollution. Flare (torch) units

According to space monitoring of the USA, for example, in 2006 in Kazakhstan 5.8 billion cubic meters of gas were burned. According to official information, in Kazakhstan in 2008, 1.8 billion cubic meters of gas were burned (in 2007 – 2.5 billion cubic meters). However, apparently, this volume is in fact much higher. For example, according to the Ministry of Environmental Protection of the Republic of Kazakhstan, in 2010, 10.5 thousand inspections of compliance with environmental legislation of oil and gas companies were carried out. In the course of them, more than 8,500 violations were found, following the consideration of which 8,300 administrative fines were imposed for a total of 5,845,079 million tenge ($ 39.6 million). According to official data of the Ministry of Oil and Gas, in 2011 – 1.2 billion m3 were burned on torches (9.7% less than in 2010). Emissions resulting from the combustion of associated petroleum gases could reach up to 10% of Kazakhstan’s total atmospheric emissions (for comparison, in Russia it was less than 2%). According to some estimates, the annual damage from actual volumes of burned associated petroleum gas exceeded the penalty payments by an order of magnitude and amounted to at least $ 2.5-3 billion. A significant concern is the negative impact of torches on the environment, which provokes the pollution of the atmosphere by the products of combustion of the oil gas – nitrogen oxides, sulfur, carbon, hydrocarbons. Pollution of soil, vegetation, reservoirs, huge consumption of oxygen, thermal radiation, burning of associated petroleum gas contributes to the greenhouse effect, causes acid precipitation and climate change. The problem of utilization of the associated gas emitted when developing fields was raised long ago. But in the conditions of the world crisis it is extremely difficult to solve it. It is no wonder that the developed countries stake on rational use of gas and some, for example, Norway has achieved nearly 100% of utilization of associated gas. Kazakhstan’s petroleum legislation was amended to prohibit burning of gas in flares and its emissions into the atmosphere from July 1, 2006. the problem of utilization of associated petroleum gas (APG) seems to be particularly relevant on the background of Kazakhstan’s ratification of the Kyoto Protocol.

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Every year in the majority of oil-producing countries of the world when developing oil fields, a significant amount of associated gas in the volume equal to consumption of natural gas in the countries of Central and South America or France and Germany combined is burnt and released into the atmosphere. According to the World Bank, 110 billion cubic meters of associated gas, or 10–13 billion cubic feet a day, are annually burnt in the world, and it, for example, is more, than it is required for internal needs of Great Britain. The volume of gas burned only in Africa would be two times more than the volume of electric energy annually produced by hydroelectric power stations of Norway. At the same time all know that burning and emission in the atmosphere of “not being of value” by-product of oil production leads to environmental pollution and enhances global greenhouse effect. Air protection in oil industry is, mainly, directed on the reduction of oil losses due to reduction of its evaporation during collection, transportation, preparation and storage. The pressurized systems of collecting oil both anticorrosive external and internal coverings of pipelines and capacities are for this purpose projected, not freezing valves are installed, the use of tanks with pontoons or floating roofs and other technical solutions is extended. In order to reduce harmful emissions into the atmosphere, the burning of oil gas in flares is reduced. There are two main ways of utilizing associated petroleum gas (APG): 1) energy way; 2) petrochemical way. The energy sector dominates, because energy production has an almost unlimited market. Associated petroleum gas is a highly calorific and environmentally friendly fuel. Considering high power consumption of oil production, there is a worldwide practice of using it to generate electricity for commercial purposes. At constantly growing electricity rates and their shares in the product cost, use of APG for generating electricity can be considered economically quite justified. The most effective way of utilization of associated petroleum gas is its processing at gas process-

Chapter 10. Oil gas as a source of air pollution. Flare (torch) units

ing plants with production of the dry stripped gas (DSG), the wide (broad) fraction of light hydrocarbons (BFLH or WFLH), the liquefied gases (LG) and the stable natural gasoline (SNG). There are also other ways of utilizing associated petroleum gas, such as: gas conservation in liquid hydrocarbons (GTL), re-injection of gas into the oil reservoir to improve oil recovery, processing associated gas in chemical raw materials, highly efficient processing of associated petroleum gas into synthetic liquid hydrocarbons. Kazakhstan has gas reserves of 3.9 trillion m3 (about 2% of the world’s reserves). To a large extent, this is due to the fact that the oil and oil and gas condensate fields on its territory are characterized by a high gas factor. 90% of the gas produced in Kazakhstan is associated petroleum gas. Depending on the area of the field, per ton of recovered oil there can be from 25 to 1,000 m3 of associated gas, which, moreover, is characterized by a high content of sulfur dioxide and methane. About 30% of the produced associated petroleum gas is pumped back into the reservoir to maintain the reservoir pressure. About 15% is used for its own technological needs, electricity generation, including burning of a small part. Commodity gas accounts for about 55% of production. To collect and process the associated gas, an expensive special infrastructure is needed, which is why it has been easier for oil producers to burn it as waste for many years. And this despite the fact that the products of APG combustion (they contain up to 250 substances harmful to human health) are one of the main pollutants of the atmosphere. Thus, coordinated efforts on the part of the state, oil and gas producers, technology suppliers and the international community, which will result in economic, energy and environmental efficiency, are needed to solve the problem of rational use of APG. The main directions of state policy, which are necessary to solve the problem, should be as follows: – definition of APG as a mineral; – introduction of a pricing system, mutually beneficial for companies and subjects of natural monopoly; – development and implementation of requirements, including methodological ones, for the introduction and order of providing in-

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strumental records of the volumes of extraction, use, and burning of resources; – improvement of the order of access of oil companies to production capacities for APG processing and transportation; – development and implementation of state control and monitoring of APG utilization processes; – development of mechanisms, stimulation of investment projects for APG use, including infrastructure development, application of innovative technologies and equipment; – setting of quantitative indicators of APG use and the requirement of effective use in all licenses for the right to use subsoil; – the use of approaches adopted in international practice that contribute to the solution of the problem, in particular, the mechanisms of the Kyoto Protocol. To date, in accordance with the law of Kazakhstan, subsoil users are obliged to envisage programs for the development of associated gas processing, subject to approval by the authorized body in the field of oil and gas and coordination with authorized bodies for studying and using subsoil in the field of environmental protection. Programs should be updated every three years in order to manage associated gas efficiently and reduce the harmful impact on the environment by reducing the volume of its incineration or recycling (disposal). The effect of reducing carbon dioxide emissions caused by gas flaring would be equivalent to stopping the operation of about 70 million cars, which would mitigate the effects of climate change. 10.1. Flare (torch) units 10.1.1. Classification of flare plants

By the location of the flare torch, the flare units are divided into high-altitude (Fig. 23) and ground-based. In high-altitude flares, the torch burner is located at the top of the flare pipe; the products of combustion flow directly into the atmosphere. In land installations, the

Chapter 10. Oil gas as a source of air pollution. Flare (torch) units

burner is located at a short distance from the ground, and the combustion products are discharged into the atmosphere through a chimney.

Figure 23. The process of gas burning on a flare unit

Special safety measures must be taken when hydrocarbons are burnt in land-based flares. In this case, the torch burner is installed in a bowl with a height of about 2 m and the composition of the gas contained therein is constantly monitored to prevent hydrocarbons from escaping into the environment. To exclude the danger of ignition of gases and vapors released from safety valves and process installations, as well as the harmful effect of the thermal flame radiation on the personnel, a free zone is provided around the flare units. Typically, for ground flare installations, a zone of a radius not less than 50 m is required, and for high-altitude flares, a radius of 30-40 m is required. High-altitude flares can be divided into medium (4-25 m) and high (more than 25 m). In some torch installations, the height of the flare pipe is 80-120 m. At the facilities of the oil and gas industry torch installations are used: – low pressure – for maintenance of workshops and installations, working under pressure up to 0.2 MPa;

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Actual ecological aspects of petrochemical manufactures

– high pressure – for the maintenance of workshops and installations operating at pressures above 0.2 MPa. Flare gases from low and high pressure systems can (if possible) be collected in a gas tank for further targeted use (at a chemical plant). The following requirements are imposed on flare plants: – Completeness of combustion, excluding the formation of aldehydes, acids, smoke, soot and other harmful intermediates; – stability of the flame when the flow rate and composition of the discharged gases change; – safe ignition, noiselessness and no bright glow. In practice, various flare systems are used. Consider two of them: 1) a system with the discharge of gases into the flare pipe; 2) a system for high-pressure gases with flaring gases for processing or incineration in boiler plants. The vented gases pass a separator before entering the flare. Condensate from the separator is returned to production or disposed of in a different way or drained into the sewage system. The flare pipe is equipped with on-duty and pilot burners. Such a system is used when the gases are not disposed of (or are not recyclable) or when the pressure in the process units is not sufficient to supply the flare gas to the gas tank. In the systems of a different type, gases enter the separator, where they are separated from the condensate. The bulk of the gas is sent to the consumer, and the excess is discharged into the flare through the control valve. 10.1.2. Impact of flare installations on people, animals and the entire environment

The impact of thermal irradiation from torches is extremely dangerous for humans, animals and the entire environment. In a radius of 50-100 m from the torch, vegetation dies. The safety of operating the flare systems depends on the correct choice of the operating parameters:

Chapter 10. Oil gas as a source of air pollution. Flare (torch) units

– diameter of the barrel of the torch, which should provide a stable flame under conditions of variable load and composition; – the height of the trunk; – the distance around the barrel, where thermal radiation will be safe. The velocity of the gas in the flare pipe, regardless of the load oscillations, must always be greater than the velocity of the flame propagation, but less than a certain limiting value at which flame separation is possible. The experimental data on the rates of flame separation for flare pipes are absent. In practice, it is assumed that the flame will be stable at a gas velocity at the outlet of the pipe not exceeding 20-30% of the sound velocity in the same gas. Extensive experimental material was collected by American researchers for flare pipes of gas and oil refineries, d = 390 mm, H = 22.9 m, in particular, with respect to noise during flaring of gas. Noise at gas flaring Noise occurs when mechanical vibrations occur in solid, liquid, and gaseous media. Mechanical oscillations in the frequency range 20-20,000 Hz are perceived by the human ear as sound. After 6-7 hours of operation with a noise intensity of 80-90 dB, the functions of the autonomic nervous system and brain activity are disrupted. In Standard instructions there is the single mentioning of the allowed level of the sound in the workplaces concerning operation of the compressor. It is written that the sound level in the workplaces with a long continuous operation of the compressor should not exceed 85 dB. Noise in the discharge of gas through flare pipes with velocities exceeding the speed of sound for a given gas is due to expansion of the gas as it passes through the control valve and exits the tube. Noise during combustion (source – torch burner, high flare) is due to the non-uniform combustion process. The nonuniformity of the combustion process manifests itself in the form of separate flames. It is possible to reduce the noise level arising in case of gas expiration from a pipe by increasing the diameter of the pipe. However, at

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Actual ecological aspects of petrochemical manufactures

the same time expenditures on its mounting are increased and burning conditions are worsened. In large diameter pipes, a reset rate of at least 0.3-0.9 m/s should be maintained to exclude low-frequency oscillations. The noise created by ground flares, where the gas is burned inside the pipe, is approximately 10 dB less than the noise of high flares of the same capacity. The reason for this is probably that the flame inside the casing is protected from wind and periodic cooling. In addition, the heat from the refractory walls has a stabilizing effect on the combustion process. To reduce the noise level, whenever possible, try to increase the gas release time. To reduce the noise level on the waste pipes install silencers. Flare installations are characterized by an increased degree of danger compared to other process equipment. The maximum danger of an explosion occurs when a mixture of flammable gas and air is formed in the flare units. If an inert gas is added to such a mixture, the mixture becomes non-flammable at a certain content. The amount of inert gas is determined by its type and composition of the combustible gas and is 50-75%. The formation of explosive mixtures in flare plants is mainly due to the ingress of oxygen in them. The danger of atmospheric air penetration into flare systems arises first of all in the case of high wind, low flow rate of the discharged gas and the release of gases with a relative air density less than 1 or heated gases. Air in the flare system can get mainly through the flare pipe section or through leaks in case of leakage of the equipment. In the latter case, air is sucked into the unit due to vacuum in the flare pipe. Another factor contributing to the increased danger of flare installations is a constantly burning torch (open fire). To reduce the risk of explosion, the flare system is constantly purged with an inert or fuel gas. In addition, to limit the spread of the flame set hydraulic locks, labyrinth seals, flame arresters and other devices. One of the causes of accidents in flare plants is the clogging (freezing) of flare pipelines. Therefore, pipelines should be tilted and have

Chapter 10. Oil gas as a source of air pollution. Flare (torch) units

no pockets. In all cases where water can enter the system from outside (flushing, steaming), the pipelines should be checked for moisture. Condensate vapor (in winter) can quickly turn into ice. In addition, condensation of steam can lead to the creation of a vacuum in the flare system and air suction. Contact with a flare pipeline of crude oil can lead to plugging of the flare system. When assessing the real hazard, it should be borne in mind that an explosion is impossible if the oxygen content is below the so-called oxygen limit, which depends on the composition of the mixture: for alkanes, the oxygen limit is always above 10%, for carbon monoxide, it is 5-10%. In practice, it is assumed that with the discharge of alkanes, high flare pipes are safe if the oxygen content at a distance of 7.5 m from the top of the pipe does not exceed 6% vol. In the event of emergency discharge of large quantities of gas into the flare, personnel during the maintenance of equipment or evacuation should not be exposed to significant heat radiation. For this, the flare pipe should be sufficiently high, or, if this is not possible, protective measures should be taken. The torch can be considered as a point source of release and it is possible to calculate for it zones in which it is necessary to provide protection of the personnel and equipment. Questions for self-checking: 1. List two main ways of utilizing associated petroleum gas (APG). 2. List the main directions of state policy that are necessary to solve the problem of rational use of associated petroleum gas. 3. Describe the principle of flare (torch) units work. 4. Describe classification of flare plants. 5. List the requirements imposed on flare units. 6. Explain the nature of the impact of flare systems on vegetation. 7. Describe the influence of flare installations on humans, animals and the entire environment. 8. Tell about the influence of noise at flaring of gas on the environment. 9. Tell about the ways to reduce the noise impact of flare systems. 10. What is the reason for the occurrence of accidents on flare systems?

165

Chapter 11

THE MAIN AIR POLLUTANTS

11.1. Sulfur dioxide and hydrogen sulfide

Sulfur dioxide primarily affects the mucosa of the upper respiratory tract. Remains of gas can penetrate further into the lungs. Significant and chronic pollution with sulfurous anhydride can cause bronchial blockage, increased resistance to air flow in the airways, disruption of the function of the ciliary epithelium, and increase in the secretion of mucus. When the background contamination with sulfur dioxide and suspended particles is critical, the concentration of 0.1 mg/m3 should be considered. With this threshold is exceeded, one should expect a more frequent manifestation of symptoms of pulmonary diseases and even the appearance of pathologies, especially in infants and children. Despite the fact that the contribution of oil refineries and petrochemical plants to the overall release of sulfur compounds is relatively small (5% of total emissions of fuel and energy stations), a number of factors make it necessary to implement measures to reduce emissions already at medium-sized enterprises. These factors include, in particular, unfavorable terrain, meteorological conditions, etc. By quantity and composition the sources of emitted pollution of sulfur-containing gases can be subdivided into three basic groups: • flue gases of boiler units, process furnaces, furnaces for burning oil sludge, flare systems; • off-gases of regeneration of catalysts on cracking installations; 166

Chapter 11. The main air pollutants

• tail gases of installations of production of sulfuric acid and element sulfur (Claus’s installation). The main sources of sulfur dioxide emissions are (%): – furnace chimneys (56.9); – flare risers (19.9); – regenerators of catalytic cracking units. It should be noted that in the process of fuel combustion, along with dioxide, sulfur trioxide (1-5%) is formed by homogeneous oxidation of sulfur dioxide by molecular or atomic oxygen, as well as by heterogeneous catalytic oxidation of sulfur dioxide. In oil refineries, the main sources of hydrogen sulphide are: • crude gas from installations for utilization of torch gases; • saturated solutions of monoethanol amine (MEA); • hydrogen sulfide-containing gas from technological installations for cleaning and fractionating of gases. Hydrogen sulphide also enters the atmosphere through its evaporation from sulphurous alkaline wastewater and process condensates, through leakage of process equipment (pumps, compressors, fittings), from primary oil refining and hydrotreating, thermocracking, monoethanol cleaning and reservoirs together with petroleum products. A significant source of hydrogen sulfide emissions may be mixing barocondensators, as well as sulfur production plants.

11.2. Nitrogen oxides

Large amounts of nitrogen oxides are emitted by enterprises. Nitrogen dioxide and its photochemical derivatives affect not only the respiratory system, but also the organs of vision. At low doses, allergies and irritations are typical, with large doses – bronchitis and tracheitis. Starting at 0.15 mg/m3, prolonged exposure to nitrogen oxides causes an increase in the frequency of violations of respiratory functions and diseases of bronchitis. Nitrogen dioxide is toxic, and in sunlight it is converted into oxide with a release of ozone, which participates in the formation of photochemical smog. Simultaneous emissions of nitro-

167

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Actual ecological aspects of petrochemical manufactures

gen oxides and sulfur cause the precipitation of acid rain. Annually in industrialized countries up to 50 million tons of nitrogen oxides are emitted into the air basin, which exceeds their natural background in the air of settlements. The main sources of nitrogen oxide emissions are: – technological furnaces (72.6%), – gas engine compressors (14%), – flare risers (5.4%). In general, the NO formation reaction can be represented by the following equation (2): О2 + N2 ↔ 2NO – 180 kJ/mol

(2)

The formation of NO from fuel proceeds in two stages: • gasification of fuel oil droplets with the release of nitrogen-containing organic compounds in the form of vapors and gases; • reactions of oxidation of vapors and gases with the formation of NO. The effect of nitrogen-containing additives to methane was studied, on the basis of which it was established: – the rate of NO production from nitrogen is higher than that from air; – the formation of fuel nitric oxide occurs mainly in the initial zone of the flare; – conversion of fuel nitrogen into NO increases with an increase in the excess air ratio, and oxygen is the determining factor in the formation of fuel nitric oxide. The term “fast” NO has appeared recently due to the instantaneous formation of a large amount of nitrogen oxide in the flame. In the general sense, “fast” NO is called nitrogen oxide, formed in the flame by a mechanism different from the schemes for the formation of “air” and “fuel” NO through the intermediate combustion products of the CN-group according to the reactions (3)-(4): H• + C ↔ CH + N•  

(3)

Chapter 11. The main air pollutants

N• + O ↔ NO + H•

(4)

These reactions proceed at high speed even at temperatures when the formation of “air” NO practically does not occur. The latter reactions here are characterized by a relatively weak temperature dependence. 11.2.1. The N2O influence on the environment. Sources of N2O in the atmosphere

Over the past decades, the influence of “gay (or laughing) gas” (previously considered innocuous) in atmospheric processes leading to ozone depletion and creation of a greenhouse effect has been revealed. Studies have shown that the residence time of N2O in the lower layers of the atmosphere is ~ 120 years, as there are no conditions for its chemical transformation there. From the troposphere, N2O gradually passes into the stratosphere, where it is partially destroyed due to photolytic dissociation, in part because of the interaction with the reactive O and •ОН particles formed during photolysis. In turn, NOx (II) can react with O3, forming O2 and NO2. The latter undergoes disproportionation under the action of solar radiation with the formation of NO and O, then a similar cycle is repeated many times. N2O is the third most common minor component of the atmosphere after CO2 and CH4. They in the aggregate provide the heat balance of the Earth. The contribution of N2O to the greenhouse effect is estimated at 6%, but it is ~ 260 times more powerful “greenhouse gas” than CO2. A study of ice in Greenland showed that the concentration of N2O in it in the last 100 years was ~ 280 billion-1 (cm3 ∙ m-3). The growth of the industry led to the formation of ~ 314 billion-1 (cm3 ∙ m-3) and is growing at a rate of 0.5-0.9 billion-1 (cm3 ∙ m-3) per year. Thus, the content of N2O is increasing by 0.2-0.3% per year. The main sources of N2O emissions are: – some chemical industries; – petrochemicals (12%);

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Actual ecological aspects of petrochemical manufactures

– power plants, including those working on petroleum fuels; – motor transport (18%); – agriculture (70%). There is a need to reduce N2O emissions by 70-80%, on the one hand, through catalytic processing, on the other – its role as an oxidizer in the catalytic oxidation of ammonia. 11.3. Carbon monoxide (II)

Carbon monoxide is the most dangerous and widespread of gaseous air pollutants. Carbon monoxide (II) is dangerous in that it combines with hemoglobin of blood, resulting in the formation of carboxyhemoglobin. An increase in the level of carboxyhemoglobin in the blood can cause disruption of the functions of the central nervous system: vision, reaction, orientation in time and space weakens. This kind of pollution is especially dangerous for patients with cardiovascular diseases. Carbon monoxide is typical for cities and is formed mainly by motor vehicle exhaust (75-97% of all carbon monoxide (II) emissions. It is also formed in industrial enterprises and refers to the products of incomplete combustion of fuel (along with technical carbon, hydrocarbons, including carcinogenic) with a lack of oxidizer (oxygen), unsatisfactory mixing of fuel with air, imperfect design of burner devices, and so forth. The conditions and mechanism for the appearance of carbon monoxide (II) can occur, presumably, according to the following scheme. Combustion of a hydrocarbon gas, which is based on methane, undergoes successive transformations: methane → formaldehyde → carbon monoxide (II) → carbon monoxide (IV). Under unfavorable conditions (lack of oxygen, cooling of the combustion zone, quality of the preliminary preparation of the gas-air mixture), the chain reaction can break off and the combustion products will contain carbon monoxide (II) and aldehydes.

Chapter 11. The main air pollutants

The main sources of atmospheric air pollution with carbon monoxide (II) are: – tubular furnaces of process units (50% of total emissions); – reactors of catalytic cracking units (12%); – exhaust gas compressors (11%); – bitumen plants (9%); – torches (18%). 11.4. Hydrocarbons 

Emissions of hydrocarbons account for more than 70% of emissions of harmful substances from oil refining and petrochemical enterprises into the atmosphere. The toxicity of hydrocarbons is enhanced by the presence of sulfur compounds, carbon monoxide in the atmosphere, which is the reason for the lower MAC (MPC) value of hydrogen sulfide in the presence of hydrocarbons than in their absence. Depending on the structure, hydrocarbons enter into one or another photochemical reaction, thereby participating in the formation of photochemical smog. From a technological point of view, hydrocarbon emissions are direct losses of oil and petroleum products. The average branch level of hydrocarbon emissions is 5.36 kg per 1 ton of processed oil. The main sources of hydrocarbon emissions into the atmosphere are: • reservoir parks (hydrocarbons are released into the atmosphere from the reservoir breathing valves due to evaporation from open surfaces); • technological installations (emissions due to leakage of process equipment, piping equipment, oil pump seals, and also from operating valves in case of emergency situations, venting from work rooms); • circulating water supply systems (evaporation of hydrocarbons in oil separators and cooling towers); • treatment facilities (evaporation from the open surfaces of oil traps, settling ponds, flotators, slurry and sludge accumulators).

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The reason for significant emissions of light hydrocarbons from process plants is the lack of proper coupling of the capacities at the stages of atmospheric distillation of oil and the stages of deep stabilization of gasolines and gas separation of light and fatty hydrocarbon gases. Thus, in the absence of a scheme and conditions for the implementation of deep stabilization of straight-run gasolines, a significant evaporation of the gases of the propane-butane fraction takes place with the simultaneous carrying away of gasoline fractions. In the case of vacuum distillation, the choice of the scheme and arrangement of the vacuum-creating systems is important, it determines not only the extent of connection of the process with the environment, but also the amount of emission of harmful substances into the environment. The existing facilities of treatment plants and circulating water supply systems are also a powerful source of atmospheric pollution by hydrocarbons: – open traps; – various ponds; – biological treatment facilities; – cooling towers and industrial sewerage wells, in which hydrocarbons and other compounds evaporate from the sewage surface. The quantities of emissions of hydrocarbons and hydrogen sulfide with the exposed surfaces of these objects are presented in tab. 15. Significant air pollution by hydrocarbons in the factories occurs when loading with railroad tank cars and tankers filled with commercial petroleum products on loading racks and berths. Table 15

Gas emission from surfaces of treatment facilities Source of gas emission 1 Sandboxes Oil Traps The receiving reservoir (oil trap)

Average concentrations of gases in air flows, mg/m3 hydrocarhydrogen bons sulphide 2 3 314 0.153 582 0.302 221

0.306

Gross gas emissions, g/h hydrocarhydrogen sulphide bons 4 5 10,600 103.3 50,700 26.7 398

0.55

Chapter 11. The main air pollutants 1 Receiving well (oil trap) Ponds of additional sludge Quartz Filters

2

3

4

5

2,204

0.306

6,470

0.9

1,800

0.203

135,700

7.35

990.5

0.510

28,600

14.7

11.5. Particulate matter (PM) or suspended solids in the air

Emissions of solids are associated primarily with chemical methods of processing hydrocarbon raw materials, especially catalytic ones. These substances consist mainly of particles with a diameter of from 0.01 to 100 microns. The chemical composition of the resulting dust is very complex and can cause an increase in the risk of lung cancer, since the analyzes usually reveal the presence of carbon compounds, saturated, aromatic and polycyclic hydrocarbons, heavy metals. An unequivocal relationship was found between the concentration of dust in the air and chronic diseases of the respiratory tract, primarily asthma, bronchitis and pulmonary emphysema. At higher doses of heavy metals, penetrating into the body with dust, disruptions in the functioning of the bloodforming organs and the central nervous system can occur. The distribution of emissions of solid substances into the atmosphere by the main sources of their release is as follows (%): – sieving units and catalyst pneumatic transport (29.5); – catalytic cracking units regenerators (23.3); – flare risers (4.7); – ventilation systems (0.7). As can be seen from the presented data, the processes of catalytic processing of crude oil are one of the main sources of emissions of catalyst dust into the atmosphere. The low efficiency of separation of catalyst dust in catalytic cracking units leads to unreasonably high losses of expensive catalysts and significant environmental pollution by solid emissions. In other words, the problem of reducing emissions

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of solids is associated primarily with the development of projects for catalytic cracking units, and especially for higher capacity plants operating on weighted and residual types of oil feedstock. 11.6. Superecotoxicants

In recent years, out of the total number of harmful substances, those that in small doses have a strong inducing or inhibiting effect on enzymes, the so-called superecotoxicants, were revealed. The most common in the environment of superecotoxicants is benzo(a)pyrene. This substance is highlighted as an indicator for the entire group of carcinogenic polyaromatic hydrocarbons (PAH) and has a MAC of 1 ng/m3. In those objects where benzo(a)pyrene is found, as a rule, there are other PAHs, among which there is one of the strongest carcinogens produced as a result of pyrolytic reactions. The main condition for the formation of PAH is high temperature – 800-1,000 °C, therefore the main sources of PAH emissions are chimneys of process furnaces and bitumen production units. Questions for self-checking: 1. How are sources of air pollution classified? 2. What are the dangers of air pollution from polycyclic aromatic hydrocarbons and particulate carbon? 3. List the gaseous substances - the main pollutants of the air basin of oil refineries. 4. Indicate the hazardous properties of oxides of sulfur, carbon and nitrogen. 5. What is the formation of nitric oxide in the processing of hydrocarbons? 6. What are the sources of air pollution with CO, nitrogen oxides, polycyclic aromatic hydrocarbons, sulfur oxides and carbon particulate matter in hydrocarbon processing plants? 7. Describe the mechanisms of formation of electronically excited particles in the upper atmosphere. 8. What is the contribution of the “laughing gas” to the destruction of the ozone layer and global warming of the Earth? 9. What is the mechanism of N2O activation in the atmosphere? 10. List the main sampling operations used to determine the pollution in the atmosphere. 11. What methods of analysis are used to determine pollutants in the atmosphere? 12. Describe the principles of operation of devices for trapping dust and gases.

Chapter 12

HARMFUL EMISSIONS FROM VEHICLES WORKING ON HYDROCARBON FUELS

12.1. The main components of the exhaust gases of transport and their influence on the environment and population

The number of cars on Earth exceeds 1 billion. The main danger of the chemical components contained in the exhaust gases is that the components are so small that they are absorbed in the blood through the lung tissue and have a harmful effect on various human organs. Pollution of the atmosphere leads to a decrease in oxygen and an increase in carbon dioxide, which entails a number of stable weather changes. Research of scientists shows, that from year to year the content of carbonic gas in atmosphere increases. This leads to the socalled “greenhouse effect”, i.e. an increase in the average annual temperature on the planet by an average of 0.8-3%, which, in turn, will lead to significant climate changes. Pollution of the air basin creates a real danger to human health. The predominant symptoms are irritation of the upper respiratory tract and eyes, asthma or allergic rhinitis, bronchitis, lung cancer, respiratory tract cancer, leading to a sharp increase in rachitis and a delay in the normal development of children. First of all, the central nervous system of a person is affected. Unlike other environmental factors, air comes into direct and rapid contact with very large, physiologically active surfaces of the human body. Every day a person inhales 15,000175

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20,000 L of air, so even relatively small amounts of any harmful substances, long inhaled with contaminated atmospheric air, adversely affect his health and often cause various diseases. To date, quite convincing material has been accumulated on the direct dependence of diseases of the respiratory, vision, digestion, heart, and blood vessels on the pollution of the atmosphere by the exhaust gases of motor vehicles. In general, emissions of pollutants and greenhouse gases into the atmosphere from industrial activities and transport are formed from the emissions of stationary and mobile sources. Petroleum fuels are among the main sources of environmental pollution. So, with the products of combustion of fuels, the atmosphere annually receives (in million tons): about 80 – sulfur oxides, 30-50 – nitrogen oxides, 300 – carbon oxide, 10-15 billion tons – carbon dioxide. Adoption of new environmental standards affects so much the state of many industries, that it requires significant changes in the technology of production of motor fuels. Road transport emissions related to emissions from mobile sources are determined by emissions of vehicle pollutants during their transport operations. Exhaust gases (off-gases) are the waste substances released by the engine, they are products of oxidation and incomplete combustion of hydrocarbonic fuel. Emissions of exhaust gases are the main reason for excess of admissible concentration of toxic substances and carcinogens in the atmosphere of the large cities, formations of smogs which are the frequent reason of poisoning in closed spaces. The amount of pollutants released into the atmosphere by vehicles is determined by the mass emission of gases and the composition of the exhaust gases. It is necessary to note 3 main sources of air pollution with the toxic substances emitted by cars: – the fulfilled gases which are going out of the muffler; – the crankcase gases coming to the atmosphere from the engine case ventilation system; – the evaporating fuel getting to a surrounding medium from the fuel system of the engine and the fuel tank.

Chapter 12. Harmful emissions from vehicles operated on hydrocarbon fuels

The work carried out showed strong air pollution in the cities. The application of satellite imagery shows a significant heterogeneity in the distribution of NO in the atmosphere, with heavier NO2 concentrating in the lower and NO in the upper layers of the atmosphere. The most dangerous consequences, from the ecological point of view, for the person and nature caused by some products of combustion of fuels are given in table16. The quality of fuels has a significant effect on the formation of harmful emissions. Undesirable is the presence in the fuels of large quantities of olefinic and aromatic hydrocarbons, sulfur, ash components. Table 16 Combustion products of fuels and their environmentally harmful effect Name Carbon oxide Sulfur oxides

Ecologically harmful consequences Toxic effect on humans and animals

Irritation of respiratory system; acid rain formation; destruction of catalytic converters Nitrogen Irritation of respiratory system; oxide the formation of acid rains and smog; participation in the destruction of the ozone screen Hydrocar- Carcinogenic action; bons participation in the creation of the greenhouse effect; formation of ozone and smog Ozone Toxic effect on flora and fauna; participation in smog formation

Technical solutions Optimization of the combustion process of fuels. Application of additives Development of fuels with reduced sulfur content Catalytic reduction of nitrogen oxides in combustion products

Reduction of saturated vapor pressure of fuels; optimization of the combustion process, the use of additives Reducing emission of ozoneforming substances: hydrocarbons and nitrogen oxides Aldehydes Irritant effect on organisms; Improving the combustion participation in the formation of smog process ComToxic effect on flora and fauna; Development of fuels not conpounds violation of the balance of microele- taining metal compounds of lead ments in water and soil; and other poisoning of afterburning catalysts metals Particulate Carcinogenic action; Decrease in ash content of fumatter and participation in the formation of smog els, reduction of sulfur and arsoot and acid rain omatic hydrocarbons content

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The qualitative and quantitative indicators of the release of harmful pollutants with exhaust gases of vehicles during their transport work are ambiguous and depend on many factors: – on the type of the used fuel; – on the design, conditions and operating conditions of the engine; – on the amount of the done work; – on the type and characteristics of the car’s movement. Therefore real quantitative assessment of emissions of pollutants and greenhouse gases in the atmosphere from the motor transport is a difficult task. Growth of environmental pollution from the motor transport and growth of the number of vehicles were the reason for toughening the requirements to qualitative ecological characteristics of products of oil-processing industry. Prior to 1987, various national fuel specifications were in force. In 1987, the first European standard EN228 for unleaded petrol was developed. The European Committee for Standardization (CEN) approved the specifications EN228 (conventional and premium gasolines), EN590 (diesel) and EN589 (liquefied gas). The main consumer of motor fuels (the most common type of petroleum products) is road transport. The differentiation of pollutants emitted by different modes of transport in the countries of the European Commonwealth is shown in tables17 and18. Table 17 Amount of pollutants emitted by passenger (g/person-km) and freight (g/ton-km) transport No 1 a b c d 2 a b c

Name Passenger transport: Railways High-speed railways Motor transport Air transport Freight transport: Railways Motor transport Water transport

SOx

NOx

Particulate matter

0.27 0.16 0.14 0.09

0.15 0.09 3.35 0.66

0.09 0.05 0.07 0.03

0.009 0.005 60.9 0.005 0.003 35.8 5.01 0.77 160.3 1.42 0.23 234.1

-

0.40 1.96 0.58

0.08 0.04 0.04

0.06 2.2 0.2

-

СО

СН

0.02 0.97 0.08

СО2

-

Chapter 12. Harmful emissions from vehicles operated on hydrocarbon fuels Table 18

Structure of air pollution sources No Source of pollution 1 2 3 4 5

Industry Transport Heat-and-power engineering Fuel combustion plants Other

USA 17 60 14 3-5 6-4

Share in total emissions, % vol. GB Germany France Italy 13 35 35 30 60 50 23 25 12 12 23 15 1-2 14-13

1-3 2

1-2 18-17

2-5 28-25

Japan 40 25 20 1-2 4-3

As a rule, from all harmful emissions of different vehicles 8090% fall on cars, 5-8% on railways, 1-2% on air transport and 1% on water transport (figures may vary for different countries). Despite the constant improvement of engines and a significant reduction in the specific consumption of fuels (almost 2 times), the consumption of motor fuels over the past 20-30 years has increased several fold. The consequences of air pollution by gas emissions of cars are manifested primarily at the local level. This is due to the fact that motor transport is a specific source of pollution, which is characterized by the following features: – low altitude emission of harmful substances, which leads to direct contact and direct effects on the person; – a relatively low degree of dispersion and removal of harmful substances from the source; – a greater degree of localization and concentration of pollutants than from the other sources; – location in areas with a high population density and high degree of concentration of industrial production; – multicomponent and high emission toxicity; – mobility, which complicates and intensifies the effect of exposure to toxic substances; – the dependence of the composition of gas emissions not only on the quality of fuel, the operating mode of the engine, but also on the parameters of the environment (air temperature, altitude above sea level);

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– the possibility of transforming the components of emissions and the formation of secondary, more toxic products. It is rather easier to fight against industrial sources of emissions as they are stationary, are characterized by high concentration of harmful substances and a small number of devices by means of which harmful substances are released to the environment. It allows us to hold more effective measures for reduction and neutralization of industrial emissions, than those from numerous mobile sources. As a result, the share of vehicles in pollution of the surface layer of atmospheric air, the most important component of the biosphere, is significantly higher than from the other sources. Sources of toxic substances entering the atmospheric air from aggregates and vehicle systems are spent crankcase gases and fuel fumes. The composition of toxic emissions from various sources using petroleum fuels is presented in table 19. The bulk of pollutants (with the exception of sulfur oxides) is emitted when internal combustion engines (ICE) operate. The exhaust gases of the engine contain more than 200 toxic chemical compounds. Of these, the following most harmful substances are taken into account: – carbon monoxide, CO, harmful contaminant contained in the exhaust gases of the engine in the highest concentration; – hydrocarbons, HC, harmful pollutants and smog-forming substances contained in exhaust gases of the engine and in fuel evaporation of the car; – oxides of nitrogen, NOx, harmful pollutants and smog-forming substances contained in the exhaust gases of the engine; – oxides of sulfur, harmful pollutants contained in the exhaust gases of the engine; – solid particles and carbon black C, harmful polluting suspended particles contained in the exhaust gases of the engine; – lead compounds, Pb, harmful pollutants contained in engine exhaust gas when using leaded gasoline; – aldehydes, RCHO, harmful pollutants contained in the exhaust gases of the engine;

Chapter 12. Harmful emissions from vehicles operated on hydrocarbon fuels

– benz (a) pyrene, a harmful carcinogenic substance contained in the composition of soot in the exhaust gases of the engine. The composition of the exhaust gases of the internal combustion engine is given in table 20. Table 19 Emissions from various sources using petroleum fuels, kg/t of fuel Name СО NOx (per NО2) SOx (per S) Hydrocarbons (HC) Aldehydes, organic acids Particulate matter (PM)

Carburetor engines 40 20 1.5 24

Diesel engines

Thermal stations

9 33 6 20

0.05 14 21 0.4

1.4

6

0.08

2

16

1.3

Table 20 Composition of exhaust gases of internal combustion engines, vol %. Components Nitrogen Oxygen Water Carbon dioxide СО NOx SOx Hydrocarbons Aldehydes Soot, g/m3 Benz(a)pyrene

Gasoline engine 74-77 0.3-8 3,55 5-12 1-10 0.1-0.5 0-0.002 0.01-0,1 0-0.2 0-0.04 to 0.00002

Diesel engine 76-78 2-18 0,5-4 1-10 0.01-0.5 0.001-0.4 0-0.03 0.01-0.5 0-0.009 0.01-1.1 to 0.00001

Except direct negative impact on health of the person, emissions of the motor transport have greenhouse and ozone-depleting effect on the atmosphere of the earth. It is connected with the content in the fulfilled gases of the engine of the following substances:

181

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Actual ecological aspects of petrochemical manufactures

– carbon dioxide CO2, the main component in the exhaust gases of the engine, creating a greenhouse effect in the atmosphere (greenhouse gas); – methane CH4; – ammonia NH3; – nitrous oxide N2O – greenhouse and ozone-depleting substances contained in the exhaust gases of the engine. The sulfur dioxide, which is formed in the combustion of sulfur-containing fuel, even in small concentration creates off-flavor in a mouth and irritates mucosas of a nose, nasopharynx, tracheas and bronchial tubes that is expressed in attacks of dry cough, a hoarseness etc. Single-pass inhalation of very high concentrations of sulfur dioxide leads to short wind and quickly coming disorder of consciousness. Concentration of 0.05 mg/l causes irritation of a mucosa of eyes and cough. The most admissible concentration of sulfur dioxide in air of the production enterprises is 0.02 mg/l. One of the most common components of gas emissions of motor vehicles is nitrogen oxides. Their share, for example, in large cities of developed countries, accounts for 48-63% of total emissions from all available sources. Nitrogen oxides are especially hazardous because: – they destroy the ozone layer in the upper atmosphere; – they have a strong toxic effect on all living things; – they together with hydrocarbons participate in the formation of photochemical smog. In the presence of nitrogen oxides in the air, the toxicity of carbon monoxide increases, and the norm for its content in the air should be reduced by a factor of 1.5, since their combined presence aggravates the effect of gases. Another, no less dangerous and most massive component of gas emissions of cars is carbon monoxide. Thus, in most large cities of the United States, motor transport accounts for 85-97% of all carbon monoxide emissions, and its concentration in gas emissions of cars is 7%. An increase in carbon monoxide emissions is observed with a decrease in the excess air ratio, low speed and idling of engines,

Chapter 12. Harmful emissions from vehicles operated on hydrocarbon fuels

an increase in the proportion of heavy fractions in the composition of motor fuels. The extreme toxicity of carbon monoxide, the lack of smell and color make this gas especially dangerous. Its ability to displace oxygen from compounds with hemoglobin is explained by an increased affinity of hemoglobin to carbon monoxide (200-300 times greater than to oxygen), resulting in the formation of carboxyhemoglobin. Carbon monoxide affects nervous and cardiovascular systems. The MAC (MPC) of carbon monoxide in the air of industrial enterprises is 0.0016% (0.02 mg/ l). With a content of 0.1% carbon monoxide in the inspired air, death occurs in 30-60 minutes, with 1% or more – instantaneously. The most numerous, massive and dangerous components of gas emissions of cars are hydrocarbons, of which more than two hundred are: > 32% are saturated hydrocarbons; ~ 27% – unsaturated hydrocarbons; – up to 4% – aromatic hydrocarbons; ~ 2% – aldehydes. Substances that do not belong to aromatic hydrocarbons have an essentially irritating effect on the body, and aromatic hydrocarbons are carcinogens. Hydrocarbons enter the environment as a result of evaporation and incomplete combustion of fuel and during formation of new compounds during the combustion of fuel. The formation of some of them, for example, polycyclic hydrocarbons, aromatic hydrocarbons, largely depends on the following factors: – characteristics and operating mode of engines; – volume of consumed fuel; – environment parameters, – the type and quality of fuel used. – evaporation and entering the combustion zone of fuels of lubricating oils. The total emissions of hydrocarbons by road make up a significant part of the pollution in many countries of the world. They account for 55-75% of the total volume of hydrocarbons coming from various sources into the atmosphere.

183

184

Actual ecological aspects of petrochemical manufactures

The special danger to the person and the environment is represented by lead and its compounds which are contained in gas emissions of cars. Compounds of lead, mainly tetraethyl lead (thermal power plant) are added to gasolines to increase their octane numbers. Lead and its compounds, getting to the organism, cause the most serious diseases (mental deficiency, change of behavioural functions of the organism, etc.). With gas emissions of motor vehicles, 37-85% of lead and its compounds contained in leaded gasolines enter the atmosphere, and their concentration in emissions is 50-1,000 μg/m3. A significant amount of these compounds get to the environment as a result of evaporation of gasolines. The total proportion of lead and carbon monoxide compounds in gas emissions of cars exceeds 75%. It is also established that when lead is completely removed, the emissions of hydrocarbons and nitrogen oxides are reduced by 30%. Therefore, the removal of lead from commercial gasoline will allow us to advance in solving the problem of environmental pollution and significantly increase the service life of engines. To assess toxicity (along with the estimate of the Maximum Permissible (Allowable) Concentration-MPC or MAC), a concentration index, a dimensionless quantity that takes into account the amount of harmful emissions and the degree of its toxicity, is used. Numerically, the concentration index is equal to the multiplicity of the dilution of exhaust gases (EG) containing the harmful component by air before reaching the MPC. 12.1.1. Emissions of Nitrogen oxides

According to the degree of toxicological effects on the human body, nitrogen oxides are classified as hazard class 3 (moderately hazardous substances). Nitrogen monoxide is a colorless gas, without taste and odor. When inhaled, NO, like CO, binds to hemoglobin, promoting the formation of methaemoglobin and blocking the transport of oxygen from

Chapter 12. Harmful emissions from vehicles operated on hydrocarbon fuels

the lungs to the tissues. Nitrogen monoxide is easily oxidized in air (especially at low temperatures) to NO2, a red-brown gas with a pungent odor, the inhalation of which weakens the sense of smell, reduces the ability of the eye to adapt to darkness, and also makes a person more susceptible to pathogens that cause respiratory problems. Combining with atmospheric moisture, NOx form weak solutions of nitrous and nitric acids, which leads to the precipitation of so-called acid rain. Under the influence of acid rain, soil acidification and depletion of nutrients, acidification of surface water bodies, degradation and complete destruction of forest areas occur. In addition, nitrogen oxides contribute to an increase in the ozone concentration in the surface layer, and also participate in the formation of photochemical smog. Acidic oxides in the ground layer of air are strong oxidants, adversely affecting the respiratory system of living organisms and plant growth, causing acid rain. Thus, the annual damage to US agriculture from increased concentrations of oxides is estimated at $ 1.9-4.3 billion. More than 30% of the acid rains in the UK is due to the presence of nitric acid in them. Therefore, in the most developed countries, the emissions of these compounds are limited and strictly monitored for their reduction. Reduction of nitrogen oxide emissions is achieved mainly by improving the design of combustion chambers, reducing the compression ratio and the excess air factor, optimizing composition of the fuel by reducing the content of aromatic compounds. Nitrogen oxides are present in the composition of exhaust gases in the form of oxide and nitrogen dioxide. They are formed as a result of reaction between atmospheric nitrogen and oxygen or water vapor at a high pressure (28-35 atm) and a temperature of 540-650°C during each compression in the cylinders. The fuel does not participate directly in this reaction. Oxides of nitrogen are very toxic. In the most typical cases, poisoning with nitrogen oxides begins with a slight cough, which after a while passes. At relatively high concentrations, irritation of the respiratory tract increases: a strong cough, sometimes headache, vomiting, etc. When poisoning with nitrogen oxide, in addition to general symptoms, dizziness and weakness are noted, the face pales, the blood pressure decreases. Inhalation for 6-8 min. of

185

186

Actual ecological aspects of petrochemical manufactures

air containing approximately 6 mg/l of nitrogen oxide and 3 mg/l for 12 min. is lethal. Poisoning with nitrogen dioxide is characterized by pulmonary edema followed by bronchopneumonia. A concentration of 0.1 mg/l of nitrogen dioxide is lethal when inhaled for an hour. MAC (MPC) of nitrogen oxides in the air of industrial enterprises is 0.005 mg/l. Under certain weather conditions, a photochemical reaction is possible, which contributes to the formation of nitrogen oxide substances that damage the mucous membrane of the eyes, as well as plants and even rubber. According to American researchers, the maximum content of nitrogen oxides in the atmosphere is (in terms of nitrogen dioxide) 0.025 mg by volume. Nitrogen oxides by the action on the human body are the most toxic components of exhaust gases, and their neutralization by catalytic decomposition or reduction becomes especially important. The main contribution to the formation of nitrogen oxides is made by high-temperature processes (T> 1,100°C) of air nitrogen oxidation according to the mechanism of Ya. B. Zel’dovich (“thermal” NOx), reactions (5)-(6). According to this mechanism, O2 dissociates into atoms at high temperatures and interacts with N2 in accordance with the following reversible chain reactions: O + N2 ↔ NO + N

(5)

N + O2 ↔ NO + O

(6)

The share of “thermal” NOx is approximately 20-40% (depending on the type of fuel) of the total amount of nitrogen oxides emitted annually to the atmosphere, the rest being “fast” and “fuel” NOx. Reactions involving hydrocarbon constituents also play an important role in the formation of NO (“fast” NOx). CH radicals existing in the flame front can react with atmospheric nitrogen forming cyanic acid, which in turn reacts according to the scheme: CH + N2 ↔ HCN + N

(7)

Chapter 12. Harmful emissions from vehicles operated on hydrocarbon fuels

N + OH ↔ H + NO

(8)

Unlike “thermal”, “fast” NOx can form at lower temperatures (~ 700 °C). The source of NO can be not only atmospheric N2, but also nitrogen, which is part of the fuel components (“fuel” NOx). The mechanism of formation of nitrogen monoxide from bound nitrogen is presented in Fig. 24. According to this scheme, formation of NO is preceded by the conversion of fuel nitrogen to ammonia and cyanic hydrogen acid. There are three main causes of NOx emissions: 1. High temperature combustion of fuels where the temperature is hot enough (above about 1,300°C/2,370°F) to oxidize some of the nitrogen in air to NOx gases. This includes burning hydrogen, as it burns at a very high temperature. 2. Burning plant material releases nitrogen oxides, as all plants contain nitrogen. 3. Chemical and industrial processes which use nitric acid, nitrates or nitrites will release NOx gases. Annually about 180 million tons of nitrogen oxides are emitted in the atmospheric air. Approximately 120 million tons of NOx are formed naturally (forest fires, vital activity of soil bacteria, volcanic activity, lightning discharges, etc.) and are evenly distributed throughout the globe. Background concentrations of NO2 over continents range from 0.4 to 9.4 μg/m3, and for NO they range from 0 to 7.4 μg/m3.

Figure 24. Mechanism of NO production from fuel nitrogen

187

188

Actual ecological aspects of petrochemical manufactures

Unlike naturally occurring nitrogen oxides, anthropogenic emissions (60 million tons of NOx) per year are concentrated mainly in the areas of human economic activity. In this regard, the concentration of NOx in large settlements is usually several times higher than the natural background values. The main anthropogenic sources of nitrogen oxides are: – transport; – power plants; – nitric acid production; – explosives; – fertilizers; – agriculture, etc. Among the anthropogenic sources, motor transport contributes most to the pollution of atmospheric air with nitrogen oxides. Such a high figure is primarily associated with the constant expansion of the world’s automobile fleet, which today has about 1.5 billion units, and by 2030 could reach 2.7 billion units. This is evidenced by the statistics: for the last 15 years, sales of cars have grown by 40.5% (from 51.55 million in 2000 to 72.41 million in 2015). The exhaust gases of vehicles, depending on the type of engine (two- or four-stroke, gasoline or diesel), operating conditions, the speed they develop, etc., on the average contain from 11 to 13 g NOx per 1 liter of fuel (tab. 21). Thus, the average car with an annual mileage of 16.7 thousand km and a fuel consumption of 10 liters for every 100 km of the path emits about 20 kg of NOx into the atmosphere. Internal combustion engines can produce all three nitrogen oxides: N2O, NO, NO2. Nitrous oxide (N2O), also known as “laughing gas” It is a serious greenhouse gas, and is defined as being 298 times as bad as CO2 because of its radiative effect, and the time taken to break it down. It is used as an anaesthetic and generally considered to be non-toxic. It reacts with vitamin B12, which may be a problem for those who are deficient. It is broken down in the stratosphere, and catalyses the breakdown of ozone. Ozone in the upper atmosphere is vital for absorbing UV rays; at the earth’s surface it is harmful.

Chapter 12. Harmful emissions from vehicles operated on hydrocarbon fuels

Nitric oxide (NO) It is readily oxidized in the atmosphere to nitrogen dioxide. It is non-toxic in small amounts, in fact it serves a vital role as a regulator within the human body. Nitrogen dioxide (NO2) It is a major pollutant and component of smog. It has brown fumes, reacts with water to produce nitric acid, which is why it is so irritating to the eyes and respiratory tract. When fuel is burnt in an engine, any sulphur will be converted into sulphur dioxide (SO2) gas. This readily dissolves in water to produce an acid, which accounts for the irritation to your respiratory tract if you inhale it. It also affects the ecology. Table 21

Compositions of exhaust gasoline and diesel engines (in the absence of a catalyst) Components of exhaust gases

kg/l of fuel

Gas engine

1

2

Diesel engine

% wt.

kg/l of fuel

% wt.

3

4

5

Conditions Temperature, °С

Tamb – 1,100

Volumetric speed, h-1

30,000 – 100,000

Tamb -650 (Tamb -420) 30,000 – 100,000

λ (air / fuel)

1 (14.7)

1.8 (26)

CO2

2.019

17.0

2.612

7.1

H2O

0.990

8.3

0.917

2.6

O2

0.13

1.1

5.554

15.0

N2

8.568

7.2

27.838

75.2

H2

42·10-3

3.5·10-2

7.0·10-4

2.0·10-3

Sum

98.4

99.9

CO

0.167

1.4

1.1·10-2

3.0·10-2

HC

1.5·10

0.13

2.5·10

7.0·10-3

1

2

3

4

-2

-3

5

189

190

Actual ecological aspects of petrochemical manufactures 1

2

Sum

3

4

1.64

5 0.074

SO2

2.4·10-4

2.0·10-3

3.7·10-3

1·10-2

Solid particles

-

-

2.1·10-3

6.0·10-3

Note: Tamb is the ambient temperature, °С; λ is the coefficient of air excess, expressing the ratio between the actual and theoretically necessary amount of air.

12.2. Euro-fuel standards for fuels

The emission standards for nitrogen oxides applied to road transport were first introduced in the European Union in 1992. Despite the fact that modern automotive technologies can significantly reduce nitrogen oxide emissions by improving the engine design and its optimal adjustment, the NOx level still exceeds the legal norms. For this reason, an increasingly urgent task is the development of new methods for additional purification. Since the reduction of nitrogen oxides to an environmentally friendly molecular nitrogen is a thermodynamically advantageous process, cleaning the car’s exhaust gases is essentially a kinetic problem, and therefore the main method of neutralizing NOx is the installation of catalytic systems. The choice of catalyst depends directly on the air/fuel ratio, the composition and temperature of the off-gases, and therefore the catalytic purification schemes for cars with petrol and diesel engines differ significantly from each other. Euro-0 is an environmental standard that regulates the content of harmful substances in the exhaust gases. It was introduced in the territory of most countries of Europe in 1988. Replaced by the Euro-1 standard in 1992. It provides emission by petrol engines: – carbon monoxide (CO) – no more than 11.2 g/(kW·h) (grams per kilowatt-hour); – hydrocarbons (СxНy) – no more than 2.4 g/(kW·h); – nitrogen oxides (NOx) – not more than 14.4 g/(kWh);

Chapter 12. Harmful emissions from vehicles operated on hydrocarbon fuels

– solid particles (particulate matter) – not regulated; – smoke – not regulated. As for the emission by diesel engines, there is no information. Euro-1 was introduced in the European Union in 1992. Replaced by the Euro-2 standard in 1995. It provides emission by petrol engines: – carbon monoxide (CO) – no more than 2.72 g/km (grams per kilometer of track); – hydrocarbons (СxНy) – no more than 0.72 g/km; – nitrogen oxides (NO) – not more than 0.27 g/km. Euro-2 was introduced in the European Union as a replacement for Euro-1 in 1995; in turn, it was replaced by the Euro-3 standard in 1999. The Euro-2 standard was adopted by the Russian government in the fall of 2005. Sales of gasoline AI-95 in Russia are prohibited by Euro-2 from January 1, 2011. In Kazakhstan this standard was adopted on July 15, 2009. Euro-3 was introduced in the European Union in 1999 and replaced by the Euro-4 standard in 2005. All vehicles manufactured in Russia or imported into Russia, starting from January 1, 2008, must meet the requirements of the Euro-3 standard. In Kazakhstan, the standard was adopted on January 1, 2013, in Azerbaijan – on July 1, 2012. Euro-4 was introduced in the European Union in 2005 as a replacement for the previous standard, Euro 3. In 2009 it was replaced by a new standard – Euro-5. Conversion to Euro-4: the procedure for the completion of wheeled vehicles, self-propelled vehicles or small vessels under the ecological standard Euro-4. It is carried out by installing special catalytic converters or filters of technological purification (magnetic, ultrasonic, etc.), which allows them to reduce fuel consumption and significantly (more than 50%) to reduce harmful emissions. Such effects are achieved due to changes in fuel quality and a number of its physical parameters. In Kazakhstan, the Euro-4 ecological standard was introduced by the Decree of the Government of the Republic of Kazakhstan No. 97 of February 6, 2013 for imported cars from July 1, 2013 and for manufactured cars – from January 1, 2014.

191

192

Actual ecological aspects of petrochemical manufactures

Euro-5 – the standard is mandatory for all new trucks sold in the EU since October 2008. For passenger cars – from September 1, 2009. In Russia, the Euro-5 standard applies to all imported cars from January 1, 2016. Euro-6. It was originally assumed that this standard of environmental regulations will come into force in Europe on December 31, 2013. But later its introduction was postponed for 2015. According to its requirements, Euro-6 is close to the current environmental standard EPA10 in the US and the Japanese Post NLT. A new European standard will facilitate the coordinated development of future uniform standards. Table 22 shows the environmental standards for passenger cars (in units of g/km). Table 22 Environmental standards for passenger cars according to Euro standards (in units of g/ km)

Carbon Ecological monoxide standard (CO)

Euro-1 Euro-2 Euro-3 Euro-4 Euro-5 Euro-6 Euro-1 Euro-2 Euro-3 Euro-4 Euro-5 Euro-6

2.72 (3.16) 1.0 0.64 0.50 0.500 0.500 2.72 (3.16) 2.2 2.3 1.0 1.000 1.000

Hydrocarbons СxНy

Volatile organic c��� ompounds

Nitrogen oxide (NOx)

For diesel engine -

For gasoline engine

0.50 0.25 0.180 0.080

-

-

-

0.20 0.10 0.100 0.100

0.068 0.068

0.15 0.08 0.060 0.060

HC+NOx

Suspended particles, particulate matter (PM)

0.97 (1.13) 0.7 0.56 0.30 0.230 0.170

0.14 (0.18) 0.08 0.05 0.025 0.005 0.005

0.97 (1.13) 0.5 -

0.005 0.005

Chapter 12. Harmful emissions from vehicles operated on hydrocarbon fuels Questions for self-checking: 1. How is the quality of gasoline related to environmental issues? 2. What is the difference between automotive and industrial pollution? 3. Explain why it is relatively easier to deal with industrial sources of emissions than with automobile ones. 4. How are harmful hydrocarbon emissions from motor transport generated? 5. Explain the term “exhaust gases (off-gases)”. 6. Name the combustion products of fuels and their environmentally harmful effect. 7. Compare the amount of pollutants emitted by passenger and freight transport. 8. Explain the consequences of air pollution by gas emissions of cars. 9. Describe the composition of exhaust gases of internal combustion engines. 10. Specify the role of tetraethyl lead in environmental pollution. What is the danger of tetraethyl lead? 11. What methods of production of unleaded gasoline are known? 12. Tell about emissions of nitrogen oxides. 13. Name the main causes of NOx emissions. 14. Explain the mechanism of NO production from fuel nitrogen. 15. What are the main anthropogenic sources of nitrogen oxides? 16. Compare the compositions of exhaust gasoline and diesel engines. 17. Indicate the most hazardous products of combustion of motor fuels in ascending MAC. 18. What are the ways to reduce gasoline evaporation? 19. What do you think caused the difference in environmental standards in Kazakhstan, Russia, the United States and European countries? 20. What standards for the quality of motor fuels exist in Kazakhstan, the CIS countries and in the developed countries of the West? 21. Describe Euro-fuel standards for fuels.

193

Chapter 13

CHARACTERISTIC OF SOURCES OF EMISSIONS OF PETROLEUM PRODUCTIONS

Petrochemical production refers to enterprises with unpleasant smells of emissions, toxic substances and carcinogens, gases. Sources of air pollution are divided into: a) sources of harmful substances; b) sources of harmful emissions. Sources of separation are technological installations, apparatuses, units, treatment plants, circulating water supply facilities and others that release harmful substances during operation. Sources of emissions are pipes, ventilation shafts, reservoir breathing valves, open surfaces of treatment facilities through which harmful substances are emitted. Depending on the type of system from which harmful substances are emitted, emissions are divided into: a) technological (tail technological, with blowing, from aircrafts, leakage of equipment leaks), which have a high concentration of harmful substances; b) ventilation (emissions of mechanical and natural ventilation with a low content of harmful substances); c) local exhaust ventilation, emissions close to technological. According to the location in the flow of wind, the sources are divided into: 194

Chapter 13. Characteristic of sources of emissions of petroleum productions

a) high (pipes 3.5 times higher than the height of buildings); b) low (the effective height of the emissions is less than the height of the circulation zone that appears above and behind the building. Depending on the temperature, the emissions are divided into: a) strongly heated (flare gases, flue gas), Δt = τ of emission – τ of ambient atmosphere ˃ 100 °С; b) heated, 20 °С ˂ Δt ˂ 100 °С; c) slightly heated, 5 ˂ Δt ˂ 20 °С; d) isothermal, Δt = 0 °C; e) cooled, Δt ˂ 0 °С. According to the mode of operation of emission sources in time: a) constant with a uniform one-time ejection; b) changing according to certain laws; d) periodic; e) salvo (volley). In terms of concentration, emissions are divided into: a) centralized (gathering in one or two pipes); b) decentralized (self-release from each unit). Emissions may be: a) organized (they are diverted through a system of gas outlets, gas dust catchers, etc.); b) unorganized (chimneys of stoves, incinerators, CHP, boiler houses, catalyst regenerators, scrubbers, absorbers, etc.). Let us consider how the scheme of distribution of concentration of harmful substances in the atmosphere from an organized high source of emission (Fig. 25) looks. Along the distance from the pipe in the direction of the spread of industrial emissions, the concentration of harmful substances in the surface layer of the atmosphere (2 m from the ground) first increases, reaches a maximum and then slowly decreases, which allows us to speak about the presence of three zones of unequal air pollution: the flare emission zone, characterized by a relatively low content of harmful substances in the surface layer of the atmosphere; the smoke zone – a zone of maximum harmful substances content and a zone of gradual reduction of pollution level.

195

196

Actual ecological aspects of petrochemical manufactures

Figure 25. Distribution of harmful substances in the atmosphere from an organized source of emission of waste gases

At oil refineries and petrochemical enterprises, industrial waste contained in gas emissions, as a rule, is not utilized, but burned in torches and released into the atmosphere. The main sources of emissions at oil refineries are open process units (equipment leaks, emergency emissions, etc.). Emissions of volatile organic impurities during the processing of oil account for 44.2% of total emissions. Processes of manufacture of coke and soot and also cracking of higher-boiling products promote the release of polynuclear aromatic hydrocarbons into the atmosphere. The largest sources of atmospheric pollution are factory tanks for storing oil and oil products. The amount of hydrocarbon emissions (kg/day) in oil refining processes at a production capacity of 32 million L/day is shown in table 23. The vast majority of substances used in oil refining and petrochemicals have fire and explosive, harmful (toxic), and carcinogenic properties. To organize safe operation with hydrocarbonic systems, i.e. to decrease the contact of the service personnel working with these

Chapter 13. Characteristic of sources of emissions of petroleum productions

substances and to carry out a complex of actions for prevention of poisonings, fires, burning and explosions, it is necessary to know specific properties of individual substances, dangerous intermediate and final products of processing. Emissions of hydrocarbons in refineries Type of production Distillation of crude oil Reforming of crude oil Catalytic cracking Burning (СО) Hydrocracking Reforming and hydrocracking of heavy fractions Hydrogen production unit Storage Other sources TOTAL

Table 23

Amount of emissions, (kg/day) 242 131 82 13 489 130 153 5,759 27,777 34,836

From the indicators of fire and explosion hazard, in accordance with the State Standard, the most applicable are: the flammability group, flash point, ignition temperature, temperature limits of autoignition. Most hydrocarbon systems belong to the group of combustible substances, i.e. such that are capable of self-combustion in the air after removal of the ignition source. The hydrocarbon systems and industries in which they are used are classified according to the degree of hazard, the indicators of which have the following definitions. The flash point is the lowest temperature of a combustible substance, at which vapor or gases are generated above its surface that can flare in the air from the ignition source, but the rate of their formation is still insufficient for sustainable combustion. The ignition temperature is a temperature of combustible substance at which it emits combustible vapors and gases with such a speed that after their inflaming from a source of ignition there is a steady combustion.

197

198

Actual ecological aspects of petrochemical manufactures

Combustible liquids with a flash point in a closed crucible not above 61 °C refer to flammable liquids (FL). FL are subdivided into: – especially dangerous – having a flash point below -18 °C; – constantly dangerous – with a flash point from-18 to 23 °C; – dangerous at elevated temperature – with a flash point from 23 to 61 °C. The flammability group, depending on the flash point, is used in determining the category of production in case of fire. Most petroleum products, along with fire hazard, have harmful properties. Harmful substances are substances which at contact with a human body, in case of violation of safety requirements, can cause production injuries, professional diseases or deviations in the state of health found by the modern methods both in the course of work, and in the remote terms of life of this and subsequent generations. Harmfulness of the substance can be judged by its maximum allowable concentrations (MAC) in the air of the working area. MAC are concentrations that, with daily (except weekend) work for 8 hours or with a different working day, but not more than 41 hours a week, cannot cause diseases or abnormalities in the state of health during the whole working period. Working zone is the space up to 2 m high over the level of the floor or the platform, which are places of constant or temporary stay during the working process. In accordance with the accepted classification, by the degree of exposure to the human body, harmful substances used in industry are divided into four hazard classes: 1 – extremely hazardous substances; 2 – highly hazardous substances; 3 – moderately hazardous substances; 4 – low-hazard substances. Table 24 shows some characteristics of the hazardous properties of individual substances used or obtained in the processing of hydrocarbon systems. Accounting for the above characteristics is an indispensable element in the design of the relevant refineries and petrochemical enterprises and their subsequent work.

n-Dodecane Isobutane

n-Heptane

Butadiene n-Butane Buten-1 n-Hexadecane n-Hexane

Benzene

1 Acetylene

Substance

77 -

-4

-26

128

-11

-

2

Flash point, °С

Concentration volumetric ignition Combustibility, limits,% inflammability, explosion hazard Lower Upper Hydrocarbons 3 4 5 Explosive sub2.50 81.0 stance Highly flammable 1.43 6.7 liquid 2.02 12.5 Combustible gas 1.5 8.5 Combustible gas 1.81 9.6 Combustible gas 0.47   Flammable liquid Highly flammable 1.24 7.5 liquid Highly flammable 1.07 6.7 liquid 0.63   Flammable liquid 1.81 8.4 Combustible gas    

 

 

100      

5

 

6

MAC mg/m3

   

 

 

4      

2

 

7

Hazard Class

Indicators of hazardous properties of individual substances used or obtained in the processing of hydrocarbon systems

   

 

3.00

1.88 2.07    

2.77

0.91

8

Density of gases (vapors) by air

Table 24

Chapter 13. Characteristic of sources of emissions of petroleum productions

199

n-tetradecane Toluene

Propane Propylene Styrene

n-Pentadecane n-pentane

n-Octane

Methane n-Nonan

p-Xylene

m-Xylene

Isopropylbenzene o-Xylene

1 Isobutylene Isopentane

0.54

1.25

4

1.06

31

103

2.31 2.30

1.47

-44

-

0.50

115

0.94

0.84

31

14

5.28

1.00

-

25

1.00

1.00

32

25

0.93

1.36

-52

36

3 1.78

2 -

6.7

 

5.2

9.5 10.3

7.8

 

3.2

 

15.0

6.0

6.0

6.0

4.2

7.6

4 9.0

5 Combustible gas Highly flammable liquid Highly flammable liquid Highly flammable liquid Highly flammable liquid Highly flammable liquid Combustible gas Highly flammable liquid Highly flammable liquid Flammable liquid Highly flammable liquid Combustible gas Combustible gas Highly flammable liquid Flammable liquid Highly flammable liquid 50

 

5

   

 

 

 

 

 

50

50

50

50

 

6 100

3

 

3

   

 

 

 

 

 

3

3

3

4

 

7 4

3.20

6.83

3.58

1.56 1.45

2.50

 

 

 

0.55

3.66

3.66

3.66

4.14

2.5

8  

200 Actual ecological aspects of petrochemical manufactures

Ethylene

Ethane Ethylbenzene

1 n-Tridecan 2,2,4-Trimethylpen-tane n-Undekan Cyclohexane

-

3.11

1.03

1.31

-18

24

0.69

62

3.07

1.0

-10

-

3 0.58

2 90

32.0

3.9

15.0

10.6

 

3.2

4  

5 Flammable liquid Highly flammable liquid Flammable liquid Highly flammable liquid Combustible gas Highly flammable liquid Explosive substance  

 

 

80

 

 

6  

 

 

 

4

 

 

7  

0.97

3.60

1.05

2.9

 

 

8   Chapter 13. Characteristic of sources of emissions of petroleum productions

201

2 49 -38 -18 38 63 28 13 8 -6 23 38 112 13 40

73 58 12 -26 20 -

1 n-Amyl alcohol Adetaldehyde Acetone n-Butyl alcohol n-Hexyl alcohol Isobutyl alcohol Isopropyl alcohol Methyl alcohol Methyethyl ketone n-Propyl alcohol Acetic acid Formaldehyde Ethylene glycol Ethanol Acetic anhydride

Ammonia Aniline Dimethylformamide 1,2-Dichloroethane Diethylamine Pyridine Hydrogen sulfide

Alcohols, acids, aldehydes, ketones 3 4 5 1.48   Highly flammable liquid 4.00 55.0 Highly flammable liquid 2.10 13.0 Highly flammable liquid 1.81 12.0 Highly flammable liquid 1.23 5.4 Flammable liquid 1.81 7.3 Highly flammable liquid 2.23 12.0 Highly flammable liquid 6.7 34.7 Highly flammable liquid 1.8 9.5 Highly flammable liquid 2.34 13.5 Highly flammable liquid 3.33 22.0 Highly flammable liquid 7.0 13.6 Combustible gas 4.29 6.35 Flammable liquid 3.61 19.0 Highly flammable liquid 1.21 9.9 Highly flammable liquid Compounds containing nitrogen, sulfur, chlorine 15.5 28.0 Combustible gas 1.32 8.3 Flammable liquid 2.35   Highly flammable liquid 4.60 16.0 Highly flammable liquid 1.77   Highly flammable liquid 1.85 12.4 Highly flammable liquid 4.0 46.0 Combustible gas 20 0.1 10 10 30 5 10

6 100 5 200 10 10 200 200 5 200 10 5 0,5   1,000   4 2 2 2 4 2 2

7 4 3 4 3 3 4 4 3 4 3 3 2   4   0.59 3.30   3.40   2.70 1.19

8 3.04 1.52 2.00 2.60   2.56 2.10 1.11 2.51 2.10 2.0 1.04 2.15 1.60 3.50

202 Actual ecological aspects of petrochemical manufactures

2 -43 25 -

25 22 35 >40 >40 150

1 Carbon disulphide Chlorobenzene Chloroethane

n-Amyl acetate n-Butyl acetate Divinyl ether Dimethyl ether Dioxan-1,4 Diethyl ether Ethyl acetate Dimethyldioxane

Gasoline Normal 80 Gasoline Premium-95 Gasoline super-98 Hydrogen Diesel fuel winter Diesel fuel summer Kerosene lighting Transformer oil Carbon monoxide (as a by-product of combustion and cracking)

4 5 50.0 Highly flammable liquid   Highly flammable liquid   Combustible gas Ethers

12.5

75.0

Flammable liquid

1.08   Highly flammable liquid 1.43 15.0 Highly flammable liquid 2.00   Highly flammable liquid 3.49   Combustible gas 1.87 23.4 Highly flammable liquid 1.90 Highly flammable liquid 2.28 16.8 Highly flammable liquid 1.97 22.0 Highly flammable liquid Petroleum products and other substances 1.05 5.16 Highly flammable liquid 1.06 5.16 Highly flammable liquid 1.05 5.16 Highly flammable liquid 4.00 75.0 Combustible gas 0.61 Highly flammable liquid Highly flammable liquid 0.64 Highly flammable liquid 0.29 Flammable liquid

3 1.33 1.40 3.92

4

4

300 20

4 4 4 -

4 4     3 4 4 3

7 2 3  

100 100 100 -

100 200     10 300 200 3

6   50  

0.9

3.60 3.60 3.60 0.66

        3.10 2.60 3.04 4.00

8 2.60     Chapter 13. Characteristic of sources of emissions of petroleum productions

203

1 Solvent P-4 (n-butyl acetate 12% toluene 62%, acetone 26%) Tetrahydrofuran White Spirit Ethylene oxide

3 1.60 1.78 0.70 3.66

2

-9

-16 >33 -

80.0

4

Highly flammable liquid Highly flammable liquid Explosive substance

Highly flammable liquid

5

100 300 1.0

6

4 4 2

7

1.52

8

204 Actual ecological aspects of petrochemical manufactures

Chapter 13. Characteristic of sources of emissions of petroleum productions

The change in the state of the biosphere occurs under the influence of natural and anthropogenic influences. Unlike natural effects, irreversible changes in the biosphere under the influence of anthropogenic factors are intense, short-lived, but can also occur over a long period of time. One of the factors of anthropogenic impact is the impact of hydrocarbon systems. By energy saturation and by its effect on nature, the processes of processing hydrocarbon systems are comparable to natural processes that take place for thousands or even millions of years. At the same time, it becomes necessary to distinguish these environmental changes from the background of natural changes, to organize a system of observations of the state of the biosphere under the influence of production. To study and solve environmental problems, it is necessary to create information systems that characterize the actual state of the environment. The monitoring of the actual state of the environment is also a key to the development, implementation and evaluation of the effectiveness of environmental protection measures. These measures are undertaken to reduce the anthropogenic pressure on the natural environment and to take decisions on environmental protection. First of all, we need information about the actual state of the environment. The main source of information characterizing the state of the environment is the results of analytical measurements. Depending on the objectives the analytical measurements can be carried out in the following purposes: – monitoring of the changes in the surrounding medium and identification of the reasons which caused them; – obtaining the secondary information (statistical processing) based on the results of observations or monitoring; – predictions of tendencies of changes in an ecological situation at various levels. The issues of environmental protection for the oil refining and petrochemical industry are increasingly important. Intensification of the technology leads to critical values of pressure parameters, temperature, the content of hazardous substances, the appearance of new, sometimes difficult-to-recycle waste; production volumes outstrip the

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improvement of environmental protection measures. This indicates an increased environmental hazard of these enterprises. The rational use of natural resources and the protection of the environment from pollution is one of the most important problems of our time, on which the health and welfare of people depends. The existing regional and city systems of monitoring consider the production enterprises as pointwise (and it is very frequent, close located) sources that do not allow us to define a contribution of each of them to environmental pollution and to estimate the influence of sources of emissions of the harmful substances located in the industrial facilities. The solution to these questions requires creation of local systems of monitoring of the surrounding medium at the level of the production enterprises. At foreign enterprises automated atmospheric quality control systems are widely used, which provide on-line monitoring of emission sources and enable forecasting of environmental situations in large areas. Such systems include, as a rule, several stationary or mobile control stations; the results of measurements are transferred to the information processing center via radio and telephone communication channels. Thus, it is possible to solve the problem of reducing environmental tension in hazardous enterprises through creation of environmental monitoring systems, and the results obtained with the help of these systems in conjunction with technological measures on improving the environmental friendliness of production will effectively improve the quality of the environment. All monitoring systems operate on unified principles that allow for a comprehensive analysis and generalization based on the measurement data, assessing and forecasting the changes that occur in ecosystems. Air pollution occurs when harmful substances, including particles and biological molecules, are introduced into the Earth’s atmosphere. It can cause diseases, allergy or death of people; it can also harm other living organisms, such as animals and food crops, and can damage the natural or built environment. Human activity and natural processes can simultaneously cause air pollution. For example, according to the

Chapter 13. Characteristic of sources of emissions of petroleum productions

report of the World Health Organization in 2014, air pollution in 2012 caused the death of about 7 million people worldwide, a rough estimate from the International Energy Agency. “Cleaning up the air we breathe prevents non-communicable diseases as well as reduces disease risks among women and vulnerable groups, including children and the elderly” (Dr. Flavia Bustreo, An Assistant Director-General Family, Women and Children’s Health) Outdoor air pollution-caused deaths – breakdown by diseases: 40% – ischaemic heart disease; 40% – stroke; 11% – chronic obstructive pulmonary disease (COPD); 6% – lung cancer; 3% – acute lower respiratory infections in children. Questions for self-checking: 1. Give a general description of petrochemical production. 2. How are emissions classified according to the type of the system from which harmful substances are released? 3. How are emission sources categorized depending on the location in the wind flow? 4. How do emissions depend on temperature? 5. How are emission sources categorized by operation over time? 6. How are emission sources classified by the degree of concentration? 7. What are the main classes of flammable substances that are common in refining and petrochemicals. 8. What are the main classes of toxic hydrocarbon systems? List the most dangerous. 9. How are flash points, flames and flammability groups determined? 10. Give the definition of MPC (MAC). 11. Are all products of hydrocarbon processing plants dangerous for nature and human health? 12. What are the peculiarities of environmental pollution? 13. What caused the need for industrial monitoring? 14. What are the features of monitoring hazardous enterprises? 15. Describe the shortcomings of modern monitoring systems.

207

Chapter 14

FEATURES OF ENVIRONMENTAL ISSUES OF PETROCHEMICAL INDUSTRIES

Environmental problems of chemical industry carry in themselves one very unpleasant property. As a result of production of this branch of economic activity of the person, the substances which are for 100% artificial and aren’t food for any organism on Earth appear or are synthesized. They do not enter the food chain, and, therefore, are not processed naturally. They can either be accumulated, or disposed of or recycled in the same artificial industrial way. To date, their processing significantly lags behind their generation and accumulation. Obviously, it is the main environmental problem. The first enterprises, from which the birth of a new chemical industry began, were the plants for the production of sulfuric acid in 1736 in the UK and in 1766 in France, and later the plants for calcined soda were built. In the middle of the XIX century the chemical industry began to produce artificial mineral fertilizers for agriculture, plastic, synthetic rubber and artificial fibers. The chemical industry has its own sub-sectors: inorganic and organic chemistry, ceramics, oil and agrochemistry, polymers, elastomers, explosives, pharmaceutical chemistry and perfumery. Its main products are ammonia, acids and alkalis, mineral fertilizers, soda, 208

Chapter 14. Features of environmental issues of petrochemical industries

chlorine, alcohols, hydrocarbons, dyes, resins, plastics, synthetic fibers, household chemicals and much more. The world’s largest chemical companies: BASF AG (Germany), BayerAG (Germany), ShellChemicals (Holland and UK), INEOS (Great Britain) and DowChemicals (USA). The problems of the chemical industry associated with the environment are not only in the products obtained, but also in waste and harmful emissions arising in the process and the result of production. These substances are secondary or by-products, but independent and, possibly, the main sources of environmental pollution. Emissions and wastes of chemical production are, in the main, mixtures, and therefore, their qualitative purification or utilization is difficult. These are carbon dioxide, nitrogen oxides and sulfur, phenols, alcohols, ethers, fluorides, ammonia, petroleum gases and other dangerous and poisonous substances. In addition, the chemical industry produces the poisonous substances themselves: not only for agricultural needs, but also for the armed forces, the storage and disposal of which requires a special regime. The technology of chemical production requires increased water consumption. It is used here for various needs, but after use it is not sufficiently purified and in the form of drains gets back into rivers and water bodies. The application of mineral fertilizers and plant protection substances during agricultural work itself has a negative impact on the composition, structure and connections, developed in the territory of the biosystem. Some species of plant and animal life are oppressed, and at the same time, the growth and reproduction of others, often uncharacteristic, is stimulated. Some of the residues of poisonous substances penetrate deep into the soil and adversely affect the deeper layers of the earth and groundwater. The other part, with thawed snow and sediments, is washed from the surface of plowing and falls into rivers and reservoirs, where they affect the soils and flora of other regions. The leading place in the industry is occupied by enterprises using hydrocarbons as raw materials.

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Actual ecological aspects of petrochemical manufactures

The area pollution by petrochemical productions can be up to 20 km from a source of emissions. The volume of emissions depends first of all on the capacity of processing equipment and its quality and also on the systems of water purification, exhaust gases and the systems of recycling. Petrochemical synthesis is the main technological process of the petrochemical industry, including such processes as pyrolysis (splitting of hydrocarbon molecules of oil and gas at a temperature of 630700°C and elevated atmospheric pressure), hydration (the addition of water to the olefin molecule occurs with heating of the feedstock under pressure 70 atm), dehydrogenation (removal of hydrogen from hydrocarbons at temperatures up to 600 °C), alkylation, polymerization, etc. Many processes occur in the presence of catalysts (chromium, nickel, cobalt, etc.). Pollution of various environmental chemicals is the main unfavorable factor of oil refining. For example: production of synthetic ethyl alcohol by direct hydration of ethylene is a source of unsaturated hydrocarbons, ammonia vapors, ethyl alcohol; production of acetylene is a source of hydrocarbons, hydrocyanic acid, dimethylamine and formic acid, dimethylformamide; production of synthetic phenol and acetone is a source of phenol, acetone, benzene, olefinic hydrocarbons, acetone phenol, isopropylbenzene, etc. Main reasons for environmental pollution by petrochemical productions: – insufficient tightness of communications, omental consolidation of pumps; – thinnesses in flange connections; – high frequency of processes and manual operations; – devices working under excessive pressure with heating of the used initial raw materials; – unsatisfactory planning of buildings, small efficiency of means of cleaning. The growth in natural gas and oil production, as well as the large demand for them in the spheres of industry and household services, led to a sharp increase in the production of plastic products and, accordingly, to increased waste.

Chapter 14. Features of environmental issues of petrochemical industries

14.1. Environmental issues in the production of plastics. Methods of utilization and disposal of plastic waste

Plastics are materials based on natural or synthetic polymers, which, under the influence of heating and pressure, can be molded into products of complex configuration and then stably retain the given shape. The production of synthetic plastics is based on polymerization, polycondensation or polyaddition reactions of low molecular weight raw materials extracted from coal, oil or natural gas, such as benzene, ethylene, phenol, acetylene and other monomers. In this case, high-molecular bonds are formed with a large number of initial molecules (Fig. 26, 27).

Figure 26. Chains of polypropylene molecules.

Plastics are inexpensive, lightweight and durable materials, which can readily be moulded into a variety of products that find use in a wide range of applications. As a consequence, production of plastics has increased markedly over the last 60 years. However, current levels of their usage and disposal generate several environmental problems.

211

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Actual ecological aspects of petrochemical manufactures

a

b Figure 27. Appearance of various plastics

Around 4 % of the world oil and gas production, a non-renewable resource, is used as feedstock for plastics and a further 3–4% is expended to provide energy for their manufacture. A major portion of plastic produced each year is used to make disposable items of packaging or other short-lived products that are discarded within a year of manufacture. Because of the durability of the polymers involved, substantial quantities of discarded end-of-life plastics are accumulating as debris in landfills and in natural habitats worldwide (Fig. 28). Recycling is one of the most important actions currently available to reduce these impacts and represents one of the most dynamic areas in the plastics industry today. Recycling provides opportunities to reduce oil usage, carbon dioxide emissions and the quantities of waste requiring disposal.

Chapter 14. Features of environmental issues of petrochemical industries

While plastics have been recycled since the 1970s, the quantities that are recycled vary geographically, according to the plastic type and application. Recycling of packaging materials has seen rapid expansion over the last decades in a number of countries. Advances in technologies and systems for the collection, sorting and reprocessing of recyclable plastics are creating new opportunities for recycling, and with the combined actions of the public, industry and governments it may be possible to divert the majority of plastic waste from landfills to recycling over the next decades.

Figure 28. Reduction of garbage in oceans is a worldwide problem

Depending on the technological process of production, the applied filler and binding (resin) distinguish plastic composite, layered and cast, and by the nature of the applied pitch (resin) – thermoreactive and thermoplastic. Plastics are still badly used as secondary raw materials. This is due, first of all, to the variety of types of plastics and products manufactured from them, as well as the complexity of composition, which makes it difficult to sort and process plastic waste, especially domestic waste.

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Actual ecological aspects of petrochemical manufactures

Meanwhile, the release of all kinds of plastic products is constantly increasing. Plastics are primarily used in the industry for the manufacture of various kinds of semi-finished products, products and parts. In some cases, they are replaced by expensive and heavier metals. Of plastic materials, various film materials for packaging are manufactured, as well as pallets, pipes, glue compositions, etc. At the same time, plastic packaging causes significant pollution of the environment, since immediately after use it goes to waste. Other plastic products become waste as they wear out. The main directions of utilization and disposal of plastic waste: burial in landfills and dumps; processing of plastic waste by factory technology; co-incineration of plastics waste with municipal waste; pyrolysis and separate combustion in special furnaces; the use of plastics wastes as a ready-made material for other technological processes. Waste disposal of plastic on grounds and dumps which is still most widespread can be considered only as a temporary measure of their utilization as plastics are exposed to decomposition extremely slowly. By this method thousands of tons of valuable secondary raw materials are withdrawn from the sphere of possible useful use. Recycling of plastic waste by factory technology is the most optimal method of using them. With all the variety of processing methods, the general scheme of the process and the equipment used in this case can be represented as follows (Fig. 29). The first stage usually includes sorting of waste by appearance, separation of non-plastic components, such as rags, remnants of paper or wooden packaging, metal objects, etc. The second stage is one of the most important in the process. As a result of one– or two-stage grinding, the material acquires dimensions sufficient to allow its further processing. In the third stage, the crushed material is subjected to washing away of organic and inorganic impurities by various solutions, detergents and water, and also separation of non-metallic impurities. The fourth stage depends on the chosen method of waste separation by types of plastics. In case the preference is given to the wet method, the waste is first separated and then dried. When using dry methods, the crushed wastes are first dried and then classified.

Chapter 14. Features of environmental issues of petrochemical industries

Figure 29. Scheme of recycling of plastic waste

The fifth and sixth steps are that the dried crushed wastes are mixed with stabilizers, dyes, fillers and other ingredients, if necessary, and granulated. At the same stage, the waste is often mixed with the commercial product. The seventh, the final stage of the process is the processing of the granulate into products. This stage is practically not much different from the processing of a commodity product in terms of the equipment used, but often requires a specific approach to the selection of processing regimes. The full implementation of the described scheme in practice is an expensive and time-consuming process, so its implementation is rather limited. Nevertheless, installations operating under this scheme in the city of Funabashi (Japan) with a capacity of 1,000 tons/year and in England with a capacity of 2,000 tons/year are known. If it is possible to achieve a sufficiently high degree of purification and separation of individual waste from mixtures, and also if the waste is pre-sorted by type of plastics, their processing is largely similar to the processing of primary plastics. One of the most essential moments is the ability of polymers to keep or change properties in the course of repeated processing as the expediency of the processing of waste in many respects depends on it. The study of the effect of the multiplicity of processing of most polymers on their physicomechanical properties showed that the change in the latter is associated, as a rule, with a decrease in the molecular weight of plastics, the branching of their structure, and a number of other indicators. The decrease in the molecular

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Actual ecological aspects of petrochemical manufactures

weight of plastics during repeated processing leads to certain changes in their strength parameters, although qualitatively they are not large. Usually, the content of waste mixed with the commercial product should not exceed 20%, since otherwise the gloss of the products obtained during the processing of the granulate deteriorates sharply, and roughness appears on their surface. The granulate of the most common polymer – polyethylene, as a rule, is processed into a film, which is used in agriculture for various purposes, or goes to the manufacture of garbage bags. For the processing of waste by injection molding, as a rule, machines operating in the extrusion type with a constantly rotating screw are used. Its design is such that it ensures spontaneous capture and homogenization of waste. A feature of the recycling of polyvinyl chloride (PVC) is the need for its additional stabilization. Wastes of soft PVC are used mainly for the production of household film products (films, tablecloths, capes, aprons, etc.). To do this, 20% of the waste is crushed by mixing rollers, mixed with commercial PVC, stabilizers, dyes and lubricants, and then passed through a system of heating and finishing rollers. Stability of quality of materials from waste allows us to use them systematically for obtaining certain plastic products. Thus, waste of polyethylene of the high pressure (PEHP) is used to produce garbage bags, pipes for protection of a cable, the household buckets, gaskets and squares, sealing profiles, films applied in agriculture and construction. Wastes of injection molded polyethylene of the low pressure (PELP) are processed into elements of construction formwork, gaskets, buckets, light fixture frames, and polypropylene waste into textile spools, sanitary ware, door handles, suitcase handles, plant boxes. Another trend in recycling is to develop methods and appropriate process equipment for recycling the waste mixture without prior separation. This makes the recycling process cheaper, but the physical-mechanical properties of products obtained in this way are much lower. Increasingly widespread for the use of plastic waste is multi-component casting, in which the product has an outer and inner layers of

Chapter 14. Features of environmental issues of petrochemical industries

various materials. The outer layer is, as a rule, high quality commercial plastics, stabilized, painted, having a good appearance. To the inner layer, high requirements are not imposed either by physical-mechanical parameters or in appearance. The material may not be stabilized and not colored. This layer often includes such cheap fillers as talcum, barium sulfate, glass and ceramic balls, foaming agent. Combustion of plastic waste with household waste One of the simplest ways to eliminate plastic waste is to burn it with household rubbish. Various designs of combustion furnaces have been developed and are continuing to be improved: bottom, rotary, nozzle, fluidized bed, etc. Preliminarily fine grinding and spraying of waste ensure, at a sufficiently high temperature, practically its complete conversion into CO2 and H2O. However burning of some types of polymers is followed by formation of toxic gases: chloride of hydrogen, nitrogen oxides, ammonia, cyanic connections, etc., which causes the necessity of actions for protection of atmospheric air. In addition, despite a significant thermal energy of burning plastics, the cost-effectiveness of this process is very low in comparison with other processes of recycling plastic waste. Nevertheless, the comparative simplicity of the organization of combustion determines a rather wide spread of this process in practice. Pyrolysis Recently, for the recycling and processing of plastic waste, thermal methods have been increasingly used. They are particularly common in cases where waste is not used in practice and cannot be recycled by processing into products or various compositions. In addition to the above method of burning plastics in conjunction with urban garbage, in the industrialized countries of Western Europe, Japan and the United States plastics is increasingly becoming pyrolyzed. To this end, various direct heating systems for plastics are being developed: for example, in the United States, rotating furnaces, vertical shaft reactors, fluidized bed systems, movable furnace grids, etc. are being investigated.

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Separate incineration of plastic waste Plastic waste can be burned in industrial furnaces of various designs: drum, multi-hinged, fluidized bed, etc. In order to improve the burning conditions of plastic waste and reduce the heat of combustion, they are sometimes pre-treated. In the USA and Canada, before baking, plastic waste is briquetted with textile and paper waste. These briquettes with a calorific value of 14.3-1.7.8 MJ/kg are burned at city thermal power plants together with coal (the ratio “coal: briquettes” is 7:1), without introducing any changes in the design of the furnaces and the technological mode of combustion. Thermal decontamination of plastics by combustion is advisable to use only in cases where more rational methods of regeneration cannot be applied – by recycling or in compositions and pyrolysis. The use of plastics wastes as a ready-made material for other technological processes Wastes from synthetic materials of light industry and other industries that do not find use can be used as valuable raw materials for other technological processes, for example, for industrial sewage treatment. Many enterprises generate waste products in the form of synthetic fibers, yarns, scraps, and so on. It is known that synthetic materials and activated carbons are the most suitable for fine wastewater purification from petroleum products. However, the latter are expensive and scarce. When synthetic fibers come into contact with petroleum products, not only molecular adsorption of petroleum products occurs, but also pronounced adhesion due to the electrical uncompensated positive charges that a synthetic fiber has. The particles of oil products possessing in sewage a negative charge are well attracted to polypropylene. Scientists have investigated the properties, filtering and sorption abilities of polyurethane foam and it forms for purification of oil-containing sewage. Waste of polyurethane foam is formed in many industries. It is widely used for purification of oil-containing sewage.

Chapter 14. Features of environmental issues of petrochemical industries

In addition to recycling and neutralization of plastic waste, it should be noted their use in construction. In most asphalt pavements, the main binders are bitumen of various nature. Having a number of advantages as a binding stone base and having a low cost, bitumen, which includes polar compounds, is characterized by insufficient water resistance. Their strength indexes are also relatively low. All this significantly worsens the properties of asphalt coatings based on bitumen and shortens the period of their operation. The use of polyolefin waste in the composition with bitumen is one of the traditional ways to modify the properties of coatings. In construction, plastics wastes are used in compositions with traditional building materials in order to modify their properties, to produce soundproof plates and panels, as well as sealants used in the construction of buildings and hydraulic structures, etc. Creation of polymers with a controlled lifetime In countries with a developed industry, the waste of polymeric materials, which are extremely slowly decomposed under natural conditions, are a serious source of environmental pollution. A particular danger is created by a single-use plastic packaging, film and packaging materials, which, as a rule, do not fall into the general collection system, making up so-called plastic garbage. To reduce the time of disposal of plastics waste, special types of polymers with a regulated service life have recently been developed and manufactured. As a rule, these are photo- and / or biodegradable polymers, which under the influence of light, heat, air and microorganisms contained in the soil decompose to low molecular weight products and are assimilated in the soil, thus including in a closed biological cycle. A distinctive feature of these polymers is the ability to maintain consumer properties during the entire required period of operation and only after expiration of this period to undergo physicochemical and biological transformations leading to destruction. Photodegradable polymers Most of the polymers currently developed with a regulated lifetime are photo-degradable polymers that, due to the presence of spe-

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Actual ecological aspects of petrochemical manufactures

cial groups or compounds in them, can decompose naturally to low molecular weight polymers (molecular weight of 1,000 or less), which are subsequently absorbed by the microorganisms of the atmosphere and soil. As a rule, special additives or polymer molecular light-sensitive groups are used to make polymers able to disintegrate under the influence of light. In order that such polymers find practical application, they must meet certain requirements: – as a result of modification of a polymer its operational characteristics shouldn’t change significantly; – the additives inserted into a polymer shouldn’t be toxic as polymers are mainly intended for production of containers and packing; – polymers should be processed by conventional methods, without undergoing decomposition; – it is necessary that products obtained from such polymers can be stored and operated for a long time in the absence of direct ultraviolet rays; – the time from the manufacture of the polymer to its destruction should be known; it is necessary to vary it within wide limits; – the decomposition products of polymers should not be toxic. From the point of view of photochemistry, the possibility of creating photorefractive polymers is due to the fact that the dissociation energy of the main C-C bond of most polymers is 350 kJ/mol, while the energy of natural ultraviolet rays is in the range of 400-600 kJ/ mol. However, this energy will be directed to the destruction of the polymer only if, firstly, the polymer is capable of absorbing light with a wavelength of 400-100 nm and, secondly, the absorbed energy is transferred to other molecules in such a way that they undergo chemical transformations, as a result of which destruction occurs. Packaging polymers with adjustable service life are stable indoors, since the window glass absorbs ultraviolet radiation, which can cause destruction. The resistance of the material to the action of sunlight behind the glass 7 mm thick is 10 times higher than in the open air. One of the most known ways of creation of the photodestroyed polymers is introduction of the groups containing carbonyl groups to a

Chapter 14. Features of environmental issues of petrochemical industries

polymeric chain. The photodestructive polymers developed in Canada with the trade name “Ecolites” provide for the introduction of photosensitive ketone groups in the polymer during copolymerization. They provide absorption by polymer of ultraviolet rays with a wavelength about 335 nm and subsequent destruction by Norrish’s reaction. The rate of photodestruction is, as a rule, proportional to the concentration of ketone groups in the polymer. Thus, by changing the composition of the copolymer, it is possible to regulate the polymer destruction time (until brittleness) from 3 to 200 days. This fact was used by the Dutch company Van Leer in the development of commercial grades of ecolites based on polystyrene (Ecolit PS), polyethylene (Ecolit PE) and polypropylene (Ecolit PP). A certain convenience of ecolites is the possibility of using them as concentrates, which are mixed in various proportions with the unmodified polymer, thereby regulating the rate of photodegradation of the resulting materials. At almost identical initial physicomechanical indexes of the photodestroyed and unmodified polymers the speed of change of strength properties of ecolites in the course of a photoaging is much higher, which is determined by a sharp decrease in the molecular weight of these materials. Under the influence of ultraviolet irradiation under artificial or natural conditions, the photodegradable materials first crack, then they are scattered into pieces of various sizes, subsequently becoming a powder. Biodegradable polymers Most of the polymer materials currently manufactured by the industry are extremely resistant to microorganisms. This is one of the main reasons for the widespread use of such materials in the national economy. However, if we consider waste polymers as a source of environmental pollution, then their dignity – biostability – turns into a serious drawback. Polymeric wastes in natural conditions decompose extremely slowly and are practically not affected by microorganisms of air and soil. One of paths of creation of biodegradable polymers is already described above: the photo-destroyed compositions after endurance

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in atmospheric conditions are so strongly destructed that are easily absorbed by the microorganisms contained in the soil. For this reason the photodestroyed polymers are often called biodestroyed. Another way to create polymers that decompose under the influence of microorganisms is to add substances to the polymer matrix that are themselves easily destroyed and digested by microorganisms. Biodegradable materials can be obtained by modifying natural polymers that, by strength, often approach plastics. In Japan, for example, graft copolymers of starch and methyl acrylate, whose films are used in agriculture for mulching soil, have been put into practical use. Films made of copolymer have high physical-mechanical parameters for a certain period of time, but under natural conditions they undergo rapid destruction. There is also the other way to make polymers biodegradable – by means of action of microorganisms capable to destroy polymers. Thus, the Japanese scientists brought by out of the soil of a bacterium which produces the enzyme splitting poly(vinyl alcohol). After decomposition polymer fragments are completely absorbed by bacteria. Using it, the Japanese firm “Kurare” applied this enzyme as additives to the active ooze in water purifying constructions to more complete sewage disposal from poly(vinyl alcohol). 14.2. Environmental characteristics of production of elastomers. Ways of waste utilization

The production of elastomers (rubber products) is one of the most significant sources of harmful emissions into the atmosphere, not in quantitative but in qualitative composition. Emissions of enterprises producing rubber products are diverse in composition and aggregate state – vapors, gases, aerosols, solids. Rubber is a collective term for macromolecular substances of natural (natural rubber, NR) or synthetic (synthetic rubber, SR) origin. Natural rubber was already used by the Mayas but was recognized as technical material first in 1851 when Charles Nelson Goodyear presented a new material produced from the milk of rubber trees, which

Chapter 14. Features of environmental issues of petrochemical industries

was obtained with more or less amounts of sulfur and vulcanized. Years later, a number of reasons including political events were responsible for the development of alternatives for natural rubber. Synthetic Rubber In 1920, the German Hermann Staudinger succeeded in determining the structure of natural rubber which was the key to the subsequent development of synthetic rubber in many countries. In Germany, this was followed by a patent for a synthetic rubber in 1929 and by the first large-scale industrial production beginning in 1939. The respective product was called Buna, from Butadiene as raw material and Natrium (sodium) as catalyst. These days, process gas chromatographs are part of the standard instrumentation of most production plants for synthetic rubber. Their objective is to continuously monitor and control processing variables such as composition of the process streams. Measuring results are essential for plant efficiency and product quality. Siemens Process Analytics is well known worldwide for its excellent process analyzer technique, application know how, service competence and expertise in engineering and manufacturing turnkey solutions including those for synthetic rubber production. The composition of gas-air emissions of rubber products includes such harmful substances as carbon black (soot), sulfur, zinc oxide, phenylnaphthylamine (neozone D), tetramethylthiuram disulfite (thiuram), a-mercaptobenzothiazole (captax), bisdisulfide (altaks), talc, gasoline, acetone, acetophenol, acrolein, acrylonitrile, dimethylamine, caprolactam, hydrogen sulphide, turpentine, toluene, methanol, benzene, phenol and many other compounds. The complex composition of the released substances is explained by a large range of products produced and, accordingly, materials and ingredients used for their manufacture, as well as by the variety of processes for obtaining rubber products. In their manufacture about 30 kinds of rubbers, more than 100 ingredients, solvents and organic additives are used. Almost all technological operations of production of rubber products are sources of harmful substances.

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This includes: – storage; – unloading; – hanging out; – transporting materials; – preparing mixtures; – molding blanks; – assembling products; – gluing with glue; – impregnating fabrics; – vulcanization and other operations. Methods of manufacturing rubber products: – assembly of separate pre-prepared parts or semi-finished products with subsequent vulcanization; – molding with simultaneous or subsequent vulcanization; – molding of rubber compound into mold by injection method fol­lo­wed by vulcanization. Preparation of details is the process of molding by injection or calendering of rubber stocks. These operations are followed by heating of a rubber stock when various gases as well as dust of talc, chalk and Kaolinum are emitted. Glue spreading, impregnation of fabrics and also processes of pasting of details at assembly of rubber goods are followed by the release of various solvents, for example, of GR-1 or GR-2 gasoline, ethyl acetate, into the atmosphere. At the enterprises producing general mechanical rubber goods, as a rule, hot vulcanization is used at a temperature of 140-170°C and elevated pressure. If during the previous technological operations the release of harmful substances into the atmosphere occurs evenly in time, during vulcanization it is not uniformly distributed. The maximum release of harmful substances occurs at the end of the vulcanization process when the lid of the vulcanization boiler is opened or when molds are opened. As the rubber products cool down, the release of vulcanization gases is significantly reduced. The quantity of harmful substances released during cooling down and the time

Chapter 14. Features of environmental issues of petrochemical industries

of their release are directly proportional to the mass of the products and their surface area. The list of hydrocarbons polluting the atmosphere is quite diverse. A significant proportion of volatile (over 50%) compounds is aromatic hydrocarbons (benzene, toluene, styrene and their derivatives); normal and isoparaffins (2,5-dimethylhexane, dodecane, 2,3,5-trimethylhexane) and olefins (octene-1, nonene-1, deten-3, etc.), most of which refer to volatile organic compounds (VOCs). To prevent contamination of the air basin, technological equipment for the production of rubber products must be sealed, equipped with standard suction and shelter. All sources of emissions are equipped with gas-dust-cleaning plants with the required degree of purification. Sewage from the production of rubber products is characterized by the presence of suspended solids, solvents and hydrocarbons in them. As a rule, they are subjected to local cleaning with subsequent post-treatment at factory or city sewage treatment plants. Rubber wastes are formed in the sphere of production – in the processes of manufacturing of rubber products (RP), consumer goods, in the tire industry and in the sphere of consumption (worn tires, rubber shoes, etc.). Burial and disposal of waste lead to contamination of soil and atmosphere by secondary pollutants. Therefore, modern RP factories provide sites or workshops for waste disposal. Rubber unvulcanized and vulcanized, rubberized non-vulcanized and vulcanized rubber, textile and rubber-metal waste are the most important compounds in the production of rubber goods. Rubber unvulcanized waste (RUVW) includes rubber compounds that are not suitable for their intended use, as well as the remains of rubber compounds. The most valuable component is rubber, the content of which reaches 90% or more. By quality, this type of waste is approaching the original rubber compounds. The RUVW processing technology consists of preparation of waste for use: sorting and purification from foreign inclusions, treatment of the treated waste on mixing rolls with the aim of averaging the physical and mechanical parameters. The heated mixture is cut from the rolls by calibrated sheets and fed to the blank site for the production of finished products.

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Rubber vulcanized waste (RVW) is a waste product of rubber compounds in the stages of vulcanization and finishing of finished products, as well as defective products. The content of rubber chemically related to other ingredients in these wastes reaches almost 50%. RVW is a valuable secondary raw material, although in quality it differs from the primary one. It is used in the manufacture of marketable rubber chips, used in enterprises as an additive to primary raw materials. Approximately 20-30% of rubber waste (among which 60% of non-vulcanized waste) is used in the enterprises themselves for the production of consumer goods (sheets of roofing fibrous, roll roofing, slabs for floors in livestock houses, slabs “Rezdor” to cover sports facilities; shock absorbers for railway sleepers; technical plate; packing rings; details of sanitary equipment; spare parts for cars: brake shoe, mud flaps, protective apron, front wings seal, protective covers, carpets; ski pads; rubber buckets; tents for baby carriages, bicycles, shopping bags, etc.). The products of vulcanized elastic and elastic rubber which lost the consumer value are processed with the production of a plastic product – regenerate, suitable for use in raw rubber compounds of rubber products. When regenerating automobile tires of a medium size, about 10 kg of rubber material can be returned. Currently, the volume of processing of worn tires is about 50% of the possible collection. It should be noted that not all worn rubber products can be used for the production of regenerate. Thus, products that have lost their elasticity and become brittle as a result of aging of rubber, articles with a low content of rubber substance, as well as products made from one regenerate, etc., are unsuitable for regeneration. At the same time, in recent decades, the production and consumption of regenerate for a number of reasons (a sharp increase in the requirements for the quality of regenerate, an increase in the costs of its production, etc.) throughout the world have been steadily declining. Metal-containing waste from regenerative industries (for example, on-board tire rings) can be used in the ferrous metallurgy. From textile waste it is possible to make plates for thermal and sound insulation, stuffing for furniture, etc.

Chapter 14. Features of environmental issues of petrochemical industries

Another direction of recycling rubber waste is their grinding in crumb. For such processing, in particular, large-sized tires without a metal cord are used. The resulting rubber chips can be processed into various building materials (bitumen-rubber mastics for anticorrosive protection of various structures, waterproofing and roofing roll materials, which can contain 10-40% of crumb), effectively used as a component of materials for pavements, used for manufacturing chemically resistant containers, certain technical materials and for other purposes. In general, despite a large scale of processing of rubber waste worldwide, their resources continue to be very significant. Therefore, the search for new ways of their utilization and processing continues. Currently, several methods for processing worn-out tires with a cord have been developed: 1. Low temperature recycling technology The results of experiments showed that crushing at low temperatures significantly improves separation of metal and textiles from rubber. In all known installations for cooling rubber, liquid nitrogen is used. But the complexity of its delivery, storage, high cost and high energy costs of its production are the main reasons restraining the introduction of low-temperature technology. To obtain temperatures in the range of 80ºC-120ºC the turborefrigerator machines are more effective as they allow to reduce the cost of obtaining cold by 3-4 times. This technology has not yet been implemented. 2. Baroestructure technology 3. Ozone processing On a significant scale, old tires are used to protect transport highways and port quays, strengthen coastal slopes, in loading and unloading operations, fish farming, etc. Rubber waste not used to produce regenerate and grind into crumb can be recycled by pyrolysis to produce various products. Such processing is applied, for example, to automobile tires with a metal cord. Thus, by thermal decomposition of rubber waste without air access at 400-450°C, a rubber oil can be obtained, which can be used as a softener in regenerative production and in rubber mixtures.

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As a result of a pyrolysis of the crushed car tires at 593-815°C, liquid hydrocarbons are produced, which are used as fuel and solid residual which can be applied instead of carbon black for production of rubber technical products. In the two-stage high temperature (900-1200°C) pyrolysis of automobile tires, carbon black can be produced for the needs of the rubber industry, tire coke with a high adsorption capacity (in particular, for heavy metal ions when extracted from industrial wastewater), combustible gas and raw materials for black. The process of pyrolysis of waste containing organic materials is now being given great attention all over the world. Semi-industrial and industrial installations of relatively low power are already operating. 14.3. Ecological characteristic of production of chemical fibers

At present, the industry produces chemical fibers in the form of monofilament (single fiber of great length), staple fibers (short cuts of single thin fibers) and filament yarns (bundles consisting of a large number of single thin fibers connected by twisting). Chemical fibers are divided into artificial and synthetic fibers. Artificial fibers are obtained by chemical processing of natural polymers (wood and cotton cellulose, proteins of vegetable and animal origin, etc.). These include viscose, copper-ammonia, acetate, protein and alginate fibers. Synthetic fibers are made from synthetic high-molecular compounds, obtained on the basis of products of processing of coal, oil and natural gas in the process of polymerization and polycondensation. For producing syntetic fibers polyamides, polyolefins, polyvinylchloride, polyacrylonitrile, poly(vinyl alcohol), fluoroplastics (fluorine-containing polymers) are used. These fibers include capron, anid, lavsan, nitron, wine, orlon, chlorine, polypropylene, polyphene, etc. The process of obtaining chemical fibers consists of the following operations: 1) preparation of spinning solutions or melts;

Chapter 14. Features of environmental issues of petrochemical industries

2) spinning the fiber; 3) finishing the molded fiber. Preparation of spinning solutions (melts) begins with transfer of initial polymer to a plastic state (solution or a melt). Then solution (melt) is purified from mechanical impurities and air bubbles and various additives are introduced for thermo – or light stabilizations of fibers, their matting, etc. The solution prepared thus or a melt is moved on a spinning apparatus for formation of fibers. Fiber molding consists in forcing the spinning solution (melt) through the small holes of the spinner cap into the medium, causing the polymer to solidify as fine fibers. Depending on the purpose and thickness of the fiber to be formed, the number of holes in the spinneret and their diameter may be different. Formation of threads is made in two ways. In the dry process the spinning solution is pressed through a spinneret into the mine where at evaporation of solvent in hot or cold air the threads are formed. In the wet method, the spinning solution is forced through the spinnerets into a precipitation bath filled with a mixture of water and solvents, where the threads solidifies. The speed of forming fibers from the solution by the “dry” method reaches 300600 m/min, by the “wet” method – 30-130 m/min. Spinning solution (melt) during transformation of jets of viscous liquid into thin fibers is simultaneously stretched (spinneret). In some cases, the fiber is additionally stretched directly after leaving the special machine, which leads to an increase in the strength of the chemical fibers and to the improvement of their textile properties. Finishing of chemical fibers consists in processing freshly formed fibers with various reagents. At the same time, low-molecular compounds, solvents are removed from the fibers, acids, salts and other substances, entrained by fibers from the precipitation bath, are washed away. To impart to the fibers such properties as softness, increased slip, surface adhesion of single fibers and others, after washing and cleaning, they are subjected to oiling. The fibers are then dried on drying rolls, cylinders or in drying chambers. After finishing and drying, some chemical fibers are subjected to additional heat treatment – ther-

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mofixing (usually in a stretched state at 100-180°C), which stabilizes the shape of the yarn, reduces the subsequent shrinkage of both the fibers themselves and their products during dry and wet treatments at elevated temperatures. The industry of chemical fibers consumes a large amount of water and various chemical products, such as sulfuric acid, sodium hydroxide, zinc sulfate, carbon disulfide, etc. For example, the consumption of fresh water in the production of viscose fibers is 300-1,000 m3 per 1 ton of products, depending on the range and used technological equipment. Water is applied to preparation of technological and liquid finishes, washing of fibers, threads, films, irrigation of spinning nests, cooling of an inventory, a sink of filtromaterial, devices, pipelines, capacities. The existing water handling in production of viscose rayons is, as a rule, unidirected and ineffective use of fresh water. The coefficient of water recirculation is 12-27%. The production of artificial fibers is associated with the release of hydrogen sulfide and carbon disulphide into the atmosphere. On the average, in the industry, 0.7-1.0 million m3 of air with a carbon disulfide concentration of 0.230.5 g/m3 is emitted per 1 ton of viscose fiber. In the production of viscose fiber emissions of carbon disulphide are about 27.5 kg/ton, and hydrogen sulfide – 3 kg/ton of product. Reduction of emissions of harmful substances can be achieved as a result of such activities as maximum sealing of spinning and finishing equipment, localization of gassing from process solutions and from freshly formed fiber, and also by transferring the by-products of xanthogenation to stable sulfur compounds (xanthate – a compound of carbon disulfide and cellulose). Ventilation emissions are cleaned at gas treatment plants where hydrogen sulphide is trapped and oxidized to elemental sulfur, and carbon disulphide is recovered. The degree of regeneration of carbon disulfide is about 95-96%. In this case, carbon disulfide returns to the production of viscose fiber, and is also used to produce carbon tetrachloride, optical glass and other products. Air after the gas cleaning devices and from local suction of spinning and finishing equipment with a small content of harmful impurities goes to the thermal and

Chapter 14. Features of environmental issues of petrochemical industries

thermocatalytic detoxification facilities, after which, passing through the high pipes, is dispersed in the atmosphere. To capture hydrogen sulphide and recover carbon disulfide from ventilation emissions, a two-stage gas purification is used. – At the first stage, hydrogen sulphide is captured, for example by a wet method (alkaline solution of hydroquinone or cobalt disulfophthalocyanine) to obtain colloidal sulfur and sodium thiosulfate in the form of marketable products. For this purpose, nozzle scrubbers of vertical and horizontal type are used. The degree of extraction of hydrogen sulfide is 95-100%. – At the second stage regeneration of carbon disulfide in adsorbers with a stationary layer of adsorbent is carried out. As an adsorbent, active carbons of the brands ART-2 and SKT-3 with a developed volume of micropores are used, which ensure a high degree of purification. One typical plant provides purification of 450-500 thousand m3/h of air to a residual carbon disulfide content of not more than 50 mg/m3. At present, filters based on chemisorption and activated carbon fiber materials are introduced to purify ventilation emissions. In the production of chemical fibers, more than 10 kinds of wastewater are formed, for example, acidic zinc-containing, slime, cellulose-containing wastewater, etc. For their purification, local installations are used with subsequent post-treatment at general and urban treatment facilities. Depending on the accepted technological scheme of wastewater treatment, three types of precipitation (sludges) are formed: cellulose, soda and lime. They are dumped and stored in sludge accumulators. 14.4. Ecological characteristic of production of artificial dyes. Manufacture of artificial mineral paints

The production of artificial mineral paints adversely affects the state of the atmosphere, the hydrosphere, and also the condition of people living near the centers of this production.

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The air emitted from the painting and drying equipment is contaminated with solvent vapor and a colorful aerosol. The greatest amount of harmful emissions is released into the air during spraying. For pneumatic manual spraying at a paint spraying capacity of 600 g/min, the amount of harmful emissions entering the air environment is 1,80 g/min in color dust, 150 g/min for dominant solvent vapors. For the electrostatic method of application with mechanical spraying at the output of paint and varnish material (PVM) of 100 g/min, the amount of harmful emissions entering the air is 0.3 g/min in color dust, 50 g/min for dominant solvent vapors. The coloring by dipping can reduce the loss of paint and varnish materials to a minimum, however, the pollution of the environment occurs due to toxic vapors of solvents released into the atmosphere. In this case, it is possible to achieve positive results when using coloring materials that emit fumes of less toxic solvents. In recent years, many paint materials have been created that have less harmful effects on the environment and its inhabitants. New technological processes of staining by the method of electrodeposition have been developed, which, with the use of membrane methods of wastewater treatment, make it possible to create practically non-waste technologies. The use of filters at the molecular level makes it possible to isolate the filtrate from the paint composition, which is used for flushing excess material that is not fixed on the product to be painted. Previously, this part of the paint composition was washed off with washing water and polluted the environment. With the use of membrane technology, the paint washed off by the filtrate returns to the paint bath and is fully used for painting. At present, technological processes for coloring powder materials and a number of other progressive methods are being intensively introduced into the industry. The harmful effects of industrial waste products of paint and varnish industries on water resources lead to serious consequences. In the production of PVM application, a large amount of water is used as a solvent for various chemicals used to pretreat the surface before painting, washing and hydrotreating air polluted with PVM aerosols and other technological needs.

Chapter 14. Features of environmental issues of petrochemical industries

In the process of using the paint equipment, waste water is periodically generated, which requires special cleaning before discharge into the sewage systems, as in the reservoirs of our country the content of toxic substances is limited. The methods of wastewater treatment depend on the composition of the contaminants in them. In the paint shops and departments, the wastewater has various impurities: the water from the preparation unit is contaminated with formulations for neutralization, phosphating; from chambers and staining installations – PVM and solvents. There are three main types of wastewater treatment plants – local, factory, district or city. The purpose of local or workshop treatment facilities is, first of all, in the decontamination of waste water or the recovery of valuable components immediately after technological installations and workshops. At local facilities, waste water is purified, which cannot be sent without prior treatment to the recycling and recycling water supply system, to general plant or district treatment facilities. These include installations for mechanical cleaning of water from coagulated paint, coagulation, filtration of washing water from electrodeposition plants, ultrafiltration, etc. Many large enterprises have general industrial wastewater treatment plants. The most modern ones include installations for mechanical, physicochemical and biological purification. District or city treatment facilities are designed for cleaning domestic and industrial wastewater. The latter regulates the content of soluble, suspended and floating substances, products that can destroy or clog communications, explosive and combustible substances, as well as temperature. The choice of cleaning method depends on the concentration of contaminants in the waste water and the amount of solid waste generated during the application of paint and varnish coatings. The problems of utilization of various PVM wastes, obtained in the processes of coloring and preparation of the surface before painting, are solved depending on the coloring technology, the type of production, its location and a number of other factors.

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The majority of PVM wastes are process losses, which depend on the coating process and the complexity of the parts to be coated. All waste to be utilized and recycled is collected and sent for disposal in a pasty or solid state. In general, waste PVM is burned in fires or with the help of special facilities, which cannot be considered rational and economical. Burning in bonfires is a laborious process that requires a lot of fuel consumption and is not harmful to the environment, so that a large number of products of incomplete combustion of substances are released into the atmosphere. The most harmless is combustion in installations of smokeless combustion of the flooded combustible wastage like “Whirlwind”. These installations are intended for local destruction of the combustible wastage containing up to 65% of water. In some cases, PVM wastes are disposed of at special sites or dumps with the permission of sanitary-epidemiological stations. However, the main direction of neutralizing industrial wastes is their use, processing and organization of low-waste production. The most rational is the recycling of PVM wastes into paintwork materials. The damage to land resources is mainly due to the emissions of PVM wastes, the drainage of chemical treatment and deactivation formations onto the soil. Waste paint and chemicals, merged on the soil, make it unsuitable for economic use for many years. Gradually, from day to day, new land plots are being alienated, where industrial waste is dumped, including PVM wastes. Questions for self-checking: 1. Name a negative feature of chemical industry which impacts the ecology. 2. Why is qualitative purification or utilization of emissions and wastes of chemical productionis very difficult? 3. Explain environmental issues in the production of plastics. 4. List the main directions of utilization and disposal of plastic waste. 5. Describe a scheme of recycling of plastic waste. 6. What are biodegradable polymers? 7. Explain why the production of elastomers (rubber products) is one of the most significant sources of harmful emissions into the atmosphere? 8. Give the environmental characteristics of the production of elastomers. 9. List the methods of manufacturing rubber products.

Chapter 14. Features of environmental issues of petrochemical industries 10. 11. 12. 13. 14. 15.

Explain specific features of sewage from the production of rubber products. Describe rubber wastes. Tell about methods for processing worn-out tires with a cord. Explain ecological characteristics of production of chemical fibers. Describe the types of chemical fibers. Give the examples. Tell about purification of ventilation emissions during production of chemical fibers. 16. Explain ecological characteristics of production of artificial dyes. 17. Name three main types of wastewater treatment plants.

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Chapter 15

METHODS OF AIR PURIFICATION FROM INDUSTRIAL EMISSIONS

15.1. General information

Industrial gas emissions can contain inorganic and organic substances toxic to biota. Among them, the most dangerous are oxides of sulfur, nitrogen, carbon (CO), ammonia, hydrogen chloride, hydrogen fluoride, chlorine, vapors of volatile organic compounds: acetone, benzene, toluene, xylene, phenol, methyl ethyl ketone, lower alcohols, heptane, carbon bisulphide, esters, halocarbons (fluorine and chlorine derivatives), gasoline. A common feature of all the contaminants in this group is that under normal atmospheric conditions (pressure, temperature) these substances are in the gaseous state in the stream of the gas being purified. These impurities differ in their solubility in water and in other physicochemical and chemical properties, which are used in the selection of the purification method. An environmentally clean process is a production or a combination of industries, as a result of the practical activities of which a negative impact on the environment does not occur or is minimized. Such low-waste technological systems provide the maximum and complex use of raw materials and energy. The methods for reducing atmospheric pollution are based on the application of specific techniques: – perfection of technological processes (work on a closed cycle, non-waste technologies); 236

Chapter 15. Methods of air purification from industrial emissions

– reduction to a minimum of the amount of waste by the integrated use of raw materials (at the petrochemical and metallurgical enterprises sulfuric acid shops using released sulfur dioxide are built); – introductions of progressive methods of combustion (smokeless suppression of coke); – use for gaseous emissions of high flues to reduce concentration of harmful substances at the Earth’s surface. But the use of high pipes leads to contamination of remote areas. The key solution of this issue is to effectively clean up harmful gases and dust before they are released into the atmosphere. Depending on the dispersed composition of dust, humidity and other factors, a suitable type of dust collector is used. At the same time, the main criterion is the degree of cleaning and economic costs (cost of equipment, installation, electricity, operating and depreciation costs). Industrial cleaning (or purification) is the purification of gases for the purpose of subsequent utilization or return to production of a separated gas or a product transformed into a harmless state. This type of purification is a necessary stage of the technological process with the technological equipment connected to each other by material flows in accordance with the strapping of the apparatus. When organizing any production, and especially low-waste and non-waste, industrial and sanitary cleaning of gas-air emissions is a necessary stage of the technological scheme. Sanitary cleaning is the purification of gas from the residual content of pollutants in the gas, which ensures compliance with the last MAC standards for the air of populated areas or industrial premises. This purification is carried out before the exhaust gases enter the atmospheric air. At this stage it is necessary to provide for the possibility of sampling gases in order to control them for the content of harmful impurities and to evaluate the efficiency of the treatment facilities. The choice of the method for purification of waste gases depends on the specific conditions of production and is determined by a number of the main factors: the volume and temperature of the exhaust gases, the aggregate state and physicochemical properties of impurities, the concentration and composition of impurities, the need to recover or

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return them to the process; capital and operating costs, environmental situation in the region. Reduction of harmful emissions by purification of industrial gaseous wastes containing toxic substances is now an indispensable requirement in all industries. In addition to mechanical, physicochemical and chemical methods for cleaning industrial waste, smoke gases of boiler rooms and all kinds of furnaces are widely used in thermal methods. 15.2. Air purification from industrial emissions

Methods of burning harmful impurities that are able to oxidize are increasingly used to clean up drainage and ventilation emissions. These methods favourably differ from the others (for example, wet cleaning in scrubbers) by a higher degree of purification, absence in most cases of corrosive media and the exclusion of waste water. As a rule, impurities are burned in chamber furnaces using gaseous or liquid fuels. Sometimes, in practice, it is possible to oxidize organic substances in gas emissions on the surface of the catalyst, which makes it possible to lower the temperature of the process. To neutralize the exhaust gases from gaseous and vaporous toxic substances, the following methods are used (tab. 25): a) mechanical (filters, electrostatic precipitators); b) physicochemical (adsorption, absorption (physical and chemisorption), membrane, electron beam, oxidative); c) biochemical; d) microbiological; e) condensation; f) compression; g) thermal; h) catalytic. Mechanical methods are designed to capture aerosols (for example, solid dust particles), but they do not provide purification from toxic gases.

Chapter 15. Methods of air purification from industrial emissions

Methods for cleaning industrial gas emissions from gaseous and vaporous contaminants Cleaning Methods Absorptive



Process type

Table 25

Devices (apparatus)

Absorption of impurities by a solvent (water) to form a solution

towers with nozzles, scrubbers, bubble-foam machines Chemisorp- Chemical interaction of impurities with towers with nozzles, tive liquid sorbents (absorbers) with the forma- scrubbers, spray devices tion of volatile or slightly soluble chemical compounds Adsorptive Adsorption of impurities on the surface of Adsorbers a solid Thermal Oxidation of pollution by air oxygen at Combustion chambers high temperatures with the formation of non-toxic (less toxic) compounds Catalytic Catalytic chemical reaction of contamina- Catalytic and thermotion with other impurities or added sub- catalytic reactors stances with the formation of non-toxic (less toxic) compounds Biochemical Transformation of impurities under the Biofilters, bioscrubbers influence of enzymes produced by microorganisms

The most suitable method for cleaning large volumes of air is adsorption. As adsorbents, silica gels, alumogels, active carbons, porous glasses, and zeolites are used. After desorption, the impurities are not disposed of, but are subjected to thermal or catalytic afterburning. The merit of this method is a high degree of purification (95-97%), and the disadvantages are the high cost of adsorbents and the process of their regeneration. The membrane (diffusion) method is based on the separation of gas mixtures using selectively permeable membranes due to the difference in permeability coefficients of the components through these membranes. Unlike filtration, where impurities are retained in front of a porous septum, in membrane methods they, under the action of some forces, pass through the partition to the other part of the apparatus.

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There are several options of the process of thermal neutralization of gases in furnaces with and without the use of catalysts. In Fig. 30 possible options of such a process are shown. According to scheme A, the waste gases are fed to the afterburner into the furnace. In the prechamber 2 they are heated by the heat generated when the fuel burns in the burner 1 and is sent to the furnace 3 where the oxidation of organic impurities ends. Flue gases are released into the atmosphere. According to scheme B, in contrast to scheme A, the gas used for cleaning is applied for fuel combustion. By Scheme B before afterburning, flue gases are preheated by the heat of the flue gases in the heat exchanger 4. Process Schemes D and E, respectively, are similar to the schemes B and C, but in the zone of the furnace 3 for the oxidation catalyst 5 is used.

Figure 30. Schemes of possible options of the process of chemical neutralization of gaseous wastes: I – gas for cleaning; II – purified gas; III – combustion air; IV – fuel; 1 – burner; 2 – prechamber; 3 – furnace; 4 – heat exchanger; 5 – catalyst.

Chapter 15. Methods of air purification from industrial emissions

15.2.1. Purification of gas emissions by the catalytic method

Among the known methods of utilization and neutralization of harmful industrial emissions, the most effective one is the deep catalytic oxidation of organic substances to carbon dioxide and water. In terms of the depth of neutralization (up to 95-100%) of harmful emissions, platinum and palladium catalysts supported on granular carriers are effective. Such catalysts are widely used in the processes of neutralizing harmful organic emissions of industry. By catalytic method, toxic components of industrial emissions are converted into substances that are harmless or less harmful to the environment by introducing catalysts into the system. The methods for selecting catalysts are very diverse, but they are all based mainly on empirical or semi-empirical methods. The activity of the catalysts is judged by the amount of the product obtained from a unit volume of the catalyst, or by the rate of the catalytic processes at which the required conversion is ensured. The rate of catalytic processes is expressed by the equation, generally accepted for all chemical reactions: ωk = kωCa1Cb2,

(9)

where С1, С2, etc., are the concentrations of substances participating in the reaction; kω is the reaction rate constant; a, b are the reaction orders for the corresponding component. The dependence of the reaction rate constant on temperature is described by the Arrhenius law: kω = ze-E / RT,

(10)

where T is the absolute temperature; R is the gas constant; E is the activation energy; z is the pre-exponential factor. The values of ​​ E and z are constants characteristic of a given chemical reaction and catalyst.

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In most cases, the catalysts can be metals or their compounds (platinum and metals of the platinum series, oxides of copper and manganese, etc.). To carry out the catalytic process, minor amounts of catalyst are required, arranged in such a way as to provide the maximum contact surface with the gas stream. Catalysts are usually made in the form of balls, rings or wire, coiled into a spiral. The catalyst can consist of a mixture of base metals with the addition of platinum and palladium, deposited in the form of an active film on a nichrome wire wound into a spiral. The volume of catalyst mass is determined on the basis of the maximum gas clearance rate, which in turn depends on the nature and concentration of harmful substances in the off-gas, the temperature and pressure of the catalytic process and the activity of the catalyst. The permissible rate of neutralization is in the range of 2,000-60,000 gas volumes per day, volume of catalytic mass per hour. Catalysts based on noble metals have become widespread in the purification of harmful emissions of industry, they have high activity at low temperatures, durability, heat resistance and ability to work stably at high volumetric velocities. Along with the platinum and palladium catalysts, oxide catalysts are known, which are also used in the purification of harmful emissions of industrial enterprises. Oxide catalysts are lower in efficiency than platinum and palladium catalysts and do not withstand long service life. The decrease in the activity of oxide catalysts is, first of all, due to surface carbonization and a change in the phase structure. Oxide catalysts are more prone to poisoning with catalysts, which include sulfur-containing compounds, especially when it comes to neutralizing refinery emissions, where sulfur-containing substances such as mercaptans, hydrogen sulphide, sulfur oxides are present. Therefore, in neutralizing harmful emissions of industrial enterprises, including refining, preference is given to catalysts containing platinum group metals in their composition. Catalytic combustion is usually used when the content of combustible organic products in the waste gases is small, and it is not advantageous to use the direct combustion method for their neutraliza-

Chapter 15. Methods of air purification from industrial emissions

tion. In this case, the process proceeds at 200-300°C, which is much less than the temperature required for complete neutralization with direct combustion in furnaces and equal to 950-1,100°C. Catalytic afterburning occurs at temperatures lower than the ignition temperature of organic substances, then cleaning is safer. Numerous studies carried out by a number of companies, in particular “Degussa” (Germany), have shown that alkaline materials and their compounds applied to various carriers (for example, metal oxides) are often more efficient and reliable, and also much cheaper than catalysts from precious metals. With such catalysts, the oxidation reaction begins at low temperatures (about 200°C), which greatly increases the possibility of their use for catalytic combustion of gases. Alumina, kieselguhr and silicates are recommended as the catalyst carrier. Flare incinerators are widely used for the destruction of toxic substances in the flue gases (see Chapter 10). To flare installations, high demands are placed on ensuring safe and reliable operation in the conditions of fire and explosion hazard of chemical plants. The fulfillment of these requirements is achieved by observing the following conditions: – the use of a special design of burner devices (burners), which ensures a stable flame regime for a wide range changes in the amount and composition of the gas to be burned; – strict adherence to the basic rules of safe operation. Depending on the height of the flare burner installation, low torches of about 4-25 m in height and high torches, which in some cases reach heights of 100 m and more, are used. At the Institute of the Catalysis of SB RAS (Novosibirsk, Russia) series of catalysts which are used in cleaning of combustion gases of various industries, including, oxide catalysts without noble metals in their compositions were developed. Over 50 years researchers of Kazakhstan have been creating and investigating (Fig. 31) efficient stable catalysts for cleaning of gas emissions of the industry and conversion of organic compounds. Thus, palladium containing catalysts were developed and tested in a

243

244

Actual ecological aspects of petrochemical manufactures

pilot installation of “Plasticsfuntitura”, Lviv, Ukraine, in the reaction of deep oxidation of styrene (225 mg/m3). At a temperature of 400°C the degree of oxidation of styrene on the catalyst reaches 94-96%. The developed palladium catalysts are not inferior in activity to the platinum catalyst. Catalysts were introduced in the Publishing House of Tashkent, Uzbekistan to neutralize the exhaust gases from toluene in place of adsorption purification, and also at the Polyester plant, “Plasticsfuntitura” (Lviv, Ukraine), to purify the ventilation emissions of the production of plastic fittings from styrene. Some samples of catalysts were introduced at the “Kuibyshev Cable” plant to neutralize tricresol and phenol in the production of enamel wires, where the oxidation degree was 97-99% at 400-400°C.

Figure 31. Installations for studying catalytic gas purification

On the pilot and experimental basis of JSC “D.V. Sokolsky IFCE” (Almaty, Kazakhstan) (Fig. 32) the full-size block catalysts on metal carriers with honeycomb channel structure were prepared and tested. The samples of catalysts were applied for pilot industrial-scale tests with JSC “Embamunaigas” (Kazakhstan) for exhaust gases on oil heating furnaces in order to reduce toxic emissions. The catalysts were prepared from the heat-resistant foil by winding a smooth and corrugated foil into a metal block of a cylindrical shape, followed by the application of active agents (based on metal compounds of Groups 7-8). The synthesized catalysts (Figs.33, 34) had high thermal and mechanical stability, developed surface area, which contributes to low pressure drop, and easiness with orientation in the reactor. Block catalysts were

Chapter 15. Methods of air purification from industrial emissions

cylindrical in shape and easy to place at the source of toxic emissions. The catalytic filters were installed directly on exhaust gas pipes of oil heating furnaces after before-the-catalyst samples were taken (Fig. 35) In order to reduce heat transfer the catalysts were wrapped with insulating mineral wool with reflective foil.

a

b

Figure 32. The equipment on the pilot and experimental installation of JSC “D.V. Sokolsky IFCE” for preparation of full-size catalysts on metal carriers: a – the centrifuge for impregnation of metal block carriers, b – the furnaces for creation full-size metal catalysts

Figure 33. Ready-to-operate full-size block catalysts on metal carriers for neutralization of industrial wastes

245

246

Actual ecological aspects of petrochemical manufactures

Figure 34. The block catalytic converter for neutralization of toxic emissions of oil heating furnaces PT 16/150 and PTB/10/64

Figure 35. Technological scheme of the installation and operation of the catalyst in the of oil heating furnace: 1 – the furnace for heating oil, 2 – a pipe, 3 – a catalytic neutralizer, 4,5 – a stream of off-gases (CO, CHx, NOx) to the catalyst, 6,7 – a stream of gases after the catalyst

Chapter 15. Methods of air purification from industrial emissions

15.3. Decrease in gas emissions of various components 15.3.1. Air purification from SO2 and H2S emissions

The main methods of protecting the air basin by reducing emissions of sulfur dioxide with flue gases: – averaging the composition of processed oils and, accordingly, residual fractions used as refinery fuel; – use of low-sulfur residual fuels; – increase in the share of gas in the fuel; – cleaning of fuel gases. Desulfurization of liquid fuels In liquid fuel (fuel oil) sulfur is found with the composition of sulfur-organic compounds (mercaptans, sulphides, etc.), as well as in the form of hydrogen sulphide and elemental sulfur; all these substances are highly soluble in hydrocarbons). Currently, two methods are used to purify liquid fuel from sulfur: – direct; – indirect. With a direct desulfurization, the liquid fuel is treated by catalytic hydrogenation, releasing sulfur in the form of hydrogen sulfide and further reducing it to elemental sulfur. The cost of processing depends on many factors (oil type, desulfurization depth, plant capacity, etc.). Such plants with a capacity of 6-10 Mt/year are operated in Japan, USA, Mexico, Venezuela and in a number of other countries. The method of indirect desulphurisation consists in distilling fuel under vacuum. The desulfurization depth reaches 0.3-0.5%. Such plants with a capacity of up to 18 Mt/year operate in some countries of the Caribbean Sea region and Japan. Desulfurization of solid fuels Coal contains sulfur in two forms: inorganic and organic. Inorganic sulfur is present in the form of pyrites, i.e. sulphides of metals, in partic-

247

248

Actual ecological aspects of petrochemical manufactures

ular, in the form of FeS2 iron sulphide, also called iron pyrites. Organic sulfur is chemically bonded to natural carbon. To remove inorganic sulfur, a special washing of coal is sufficient, carried out in several stages. Chemical removal is required to remove organic sulfur. Sulfur in the form of pyrite may constitute from 30 to 70% of the total sulfur content in coal, but usually organic and inorganic sulfur are present in equal quantities. In recent years, a large number of various methods of cleaning flue gases from sulfur based on various chemical and physical principles was developed: 1. Chemical bonding with the formation of recoverable and unregenerated waste. 2. Conversion of sulfur dioxide to trioxide in the gas phase by means of catalysts or special electrical discharges. 3. Sorption by solids (activated carbon, zeolites, resins) followed by regeneration of sorbents. 4. Sorption by liquid substances – special organic liquids (adipic acid). 5. Liquid-phase catalytic reduction of sulfur dioxide to elemental sulfur. In the industry, many industrial technologies for the removal of SO2 with acceptable technical and economic indicators have been developed. The most common method of wet cleaning of industrial gases from sulfur dioxide is the use of solutions and suspensions of compounds of alkali, alkaline earth metals, aluminum, organic substances (sulfite-bisulfite methods). When using 9.5-10% sodium hydroxide solution, 0.05-0.08% potassium permanganate is added to increase the absorption capacity. In the case of gas cleaning with the aid of soda solutions, the accumulation of sodium thiosulfate takes place. To avoid this, 1-3% of organic compounds (alcohols, aldehydes) are added to the solution. In such a solution, the rate of formation of thiosulphate is 8-9 times lower. An industrial absorption method for purifying gases from sulfur dioxide using sodium sulphite was tested. The cooled gas, purified

Chapter 15. Methods of air purification from industrial emissions

from solid particles, is sent to an absorber, irrigated with a solution of sodium sulfite. The spent solution is regenerated in the evaporator. The released concentrated sulfur dioxide is sent to produce sulfur or sulfuric acid, and the dry residue is dissolved in water and sent to the absorber for reuse. If potassium sulphite is used instead of sodium sulfite, the potassium sulfate formed as a result of gas purification can be used as a fertilizer. The main place in the world practice of desulfurization is occupied by the technology using calcite (limestone) – CaCO3 and lime – Ca (OH)2: – wet limestone; – wet calcareous; – wet-dry lime; – dry lime. To purify gases from SO2, it is proposed to use magnesium hydroxide, a calcareous suspension (20-30% CaCl2). The resulting gypsum can be used as building materials. The degree of purification is up to 98%. The purification of flue gases using a suspension of CaCO3 is proposed. For cleaning a column apparatus with a height of 36 m and a diameter of 14 m is used. The degree of purification is 90%. The factor determining the reliable operation of the column is the pH of the suspension. The highest efficiency is achieved at a pH of 3.5-4.5. To maintain the set pH value, solutions of succinic, acetic, lactic, sulfopropionic acids are introduced in the required amount. As components of the suspension, CaO + CaCO3, CaO + Ca (OH)2, CaO + MgSO4 are also used. To improve the efficiency of lime methods for cleaning gases from sulfur dioxide, various organic compounds, for example, dicarboxylic acids with dissociation constant values ​​between the values ​​of the sulfuric and carbonic acid constants, are added to the absorbent. The absorption capacity of the suspension with respect to SO2 is increased by a factor of 7-30. Cleaning of waste gases from acid impurities is possible using the ammonia method. Ammonia is injected into the gas mixture, which reacts with acidic substances to form ammonium compounds. The solid phase collected at the electrostatic precipitator is sent to regenerate ammonia, so that the flow rate of ammonia in the process is small.

249

250

Actual ecological aspects of petrochemical manufactures

A citrate method for desulfurization of flue gases containing up to 30% of wt. sulfur dioxide is proposed. The purified gas is contacted at 15-80 °C with an aqueous solution of mono- or tricalium citrate or with a mixture thereof. Desorption of sulfur dioxide is carried out by heating the solution. The gas is sent to produce sulfuric acid, elemental sulfur or liquid sulfur dioxide. To increase the effectiveness of the citrate method, citric acid is added to the solution. There are a number of effective ways to purify waste gases using waste (sludges) from various industries. For example, the purification of gases from sulfur dioxide is carried out by treating the gas stream with a suspension of red mud (Bayer process waste) consisting of oxides of silicon, iron, titanium, aluminum and sodium. The degree of gas purification from sulfur dioxide is ≥ 90%. Most dry chemisorption methods for purifying gases from acidic components are based on the chemical interaction of harmful impurities with bases, oxides and salts of alkaline and alkalineearth elements. To remove harmful impurities from gases with simultaneous drying, a mixture of sodium, potassium, ammonium and magnesium hydrogencarbonates, applied to silicon dioxide or bentonite, is used. Flue gas cleaning is carried out with powdered sodium hydrogen carbonate, calcium carbonate, calcium oxide, calcium hydroxide, which are injected directly into the combustion chamber or flue gas line. The degree of purification from sulfur dioxide reaches 85%. Solid particles are separated on filters, cyclones along with dust. As a carrier for the sour gas scavenger, wood shavings impregnated with a solution of alkali and sodium silicate in the amount of 0.13-0.78% are used. For more complete purification from sulfur dioxide, pre-cooled to 100°C flue gases are passed through the layers of sodium hydroxide, soda, limestone, activated carbon and porous glass. The degree of purification from sulfur dioxide is 90%.

Chapter 15. Methods of air purification from industrial emissions

15.3.2. Air purification from CO2

Significant progress has been achieved in the development of various adsorption materials for capturing CO2 through physical sorption at low temperatures (from 298 K up to 423 K) and high pressure. The investigated adsorbents include zeolites, structures based on carbon materials, and metal-organic framework structures. However, these materials also have insufficient adsorption capacity with respect to CO2 at atmospheric pressure and slightly elevated temperatures. Therefore, they are not suitable for conditions in the flue gas environment after combustion, where a high concentration of steam and air is observed. For processing after gas combustion, it has also been proposed to use CO2 capture by materials based on dry alkali metals. Capturing CO2 based on heterogeneous adsorption on solids can be an attractive approach with lower cost and energy consumption. Capture and conversion of CO2 into CH4 occur in the same reactor at flue gas temperatures. The surplus stock of renewable H2 is used for the methanation of trapped CO2, which can be recycled at the input to a power plant or introduced into an existing pipeline. The processes of CO2 adsorption and methanization are exothermic processes. This nanodispersed state (~3 nm) promotes chemisorption, rather than formation of carbonates. When deposited on γ-Al2O3, dispersed CaO adsorbs CO2 only as a reversibly bound structure, which differs from the monodentate carbonates, formed on volumetric CaO at the same temperature (573 K). These circumstances explain the rapid adsorption and regeneration of dispersed CaO/Al2O3 as an effective CO2 adsorbent in a bifunctional material. Hydrogenation (methanation) of CO2, also known as Sabatier reaction, is an exothermic process, which can be used for the selective catalytic methanation of H2, obtained from renewable resources.

251

252

Actual ecological aspects of petrochemical manufactures

15.3.3. Gases purification from NOx

Nitrogen oxides, like sour gas, are one of the main pollutants of the atmosphere. The most stable in the atmosphere is nitrogen oxide (IV). The maximum permissible concentration is established for all nitrogen oxides in terms of NO2 and is 0.085 mg/m3 in the air of settlements. Sources of atmospheric pollution with nitrogen oxides are the processes of fuel combustion, as well as production of nitric acid and mineral fertilizers. Common NOx absorbers are solutions of soda, caustic soda and ammonium carbonate, lime milk, etc. The process of purification of waste gases from nitrogen oxides proceeds in two stages: – first, nitrogen oxides react with water to form acids; – second stage – acid neutralization occurs. The solutions of nitrate salts formed in this way can be used in industry and agriculture. However, their processing, in particular concentrating and transporting, cause certain difficulties. A very important disadvantage of absorption methods with alkaline solutions is low efficiency (70-85%), therefore the concentration of nitrogen oxides in purified gases is much higher than MAC (MPC) and requires their repeated dilution. Adsorption methods have been used in the case of small volumes of gases. A good sorbent of nitrogen oxides is activated charcoal, but its use is hampered by light oxidizability, which can lead to strong heating and even to the ignition of coal. Silica gel adsorption properties are slightly inferior to coal, but it is more durable and not oxidized by oxygen. The carbamide method for purification of waste gases from nitrogen oxides has proven itself in various industries, but it should be noted that in the energy sector, the regulation of the combustion of fuels (due to which the amount of nitrogen oxides forming is reduced) and the ammonia-catalytic method are mainly used.

Chapter 15. Methods of air purification from industrial emissions

One of the main, well-mastered industrial methods for purification of waste gases from nitrogen oxides is their reduction on the catalyst to molecular nitrogen. If a non-selective catalyst is used, the reducing agent is consumed not only by the reduction of nitrogen, but also interacts with the oxygen normally contained in the gas stream. Hydrogen, natural gas, carbon monoxide, etc. are used as the reducing agent. Catalytic reduction to molecular nitrogen is the most environmentally friendly way to purify industrial gas emissions from nitrogen oxides. In this case, CO, H2, CH4, NH3, various gas mixtures can be used as reducing agents. The elements of the platinum subgroup on various carriers usually serve as catalysts. The process temperature ranges from 400ºC to 800ºC. In various processes, off-gases with different contents of nitrogen oxides can form. If their content is small, then relatively simple cleaning systems are used. For example, in the production of dilute nitric acid, exhaust gases with nitrogen oxides of 0.2-0.25%, oxygen up to 3%, and water vapor up to 2.0% are formed. The main component of such gases is nitrogen. To reduce nitrogen oxides, ammonia at a temperature of 120°C and a pressure of 0.3 MPa is used: 6 NO + 4 NH3 (excess) = 5 N2 + 6H2O

(9)

6 NO2 + 8 NH3 (excess) = 7 N2 + 12H2O

(10)

The remaining ammonia is oxidized by air oxygen: 4 NH3 + 3 O2 = 2 N2 + 6H2O

(11)

The gas purified from nitrogen oxides is released into the atmosphere. Since all chemical processes used in the purification scheme proceed at elevated temperatures, the gas emitted after purification is a source of energy pollution of the atmosphere. If the nitrogen oxide content in the off-gas is increased, multi-stage purification systems

253

254

Actual ecological aspects of petrochemical manufactures

are used, which are also based on the catalytic reduction of nitrogen oxides to molecular nitrogen. The catalytic reduction of NOx by ammonia, which is carried out at temperatures of 270-390°C (reactions 12-14), is worldwide used for purification of industrial gases and gases from power plants. 3N2O + 2NH3 = 4N2 + 3H2O

(12)

6NO + 4NH3 = 5N2 + 6H2O

(13)

6NO2 + 8NH3 = 7N2 + 12H2O

(14)

To increase the efficiency of the process in an oxidizing atmosphere, NH3 is taken in excess against the stoichiometric amount. At the same time, NH3 is partly spent on the side reactions of oxidation 2NH3 + 3/2O2 = N2 + 3H2O

(15)

Ammonia for toxicity is comparable to NOx: MAC (MPC) NH3 = = 20 mg/m3, MAC (MPC) NOx = 5 mg/m3. Therefore, the reduction of NOx with ammonia requires an accurate dosage of the reducing agent. For convenience of use, ammonium water or another N-containing reducing agent, for example, an aqueous urea solution, is sometimes used instead of gaseous NH3. Catalysts based on Pt, oxides of Fe, Cr, Cu, and V are used. The most studied and effectively used in the developed countries in power systems, at thermal stations and plants for the production of nitric acid are vanadium catalysts (V2O5) on granular ceramic carriers or complex oxide systems (VW-Ti-O) prepared in the form of honeycomb blocks. Reduction of emissions of nitrogen oxides in the atmosphere by controlling the combustion process Along with the installation of gas cleaning equipment at the end of the technological cycle of fuel combustion, a number of operational

Chapter 15. Methods of air purification from industrial emissions

and technological measures that significantly reduce the amount of nitrogen oxides formed during combustion are very effective. These measures include: – combustion with a low coefficient of excess air (α – alpha); – recycling of a part of flue gases to the combustion zone; – combustion of fuel in two and three stages; – use of burners, allowing us to reduce the output of NOx; – supply of moisture to the combustion zone; – intensification of radiation in the combustion chamber; – selection of the combustion chamber profile to which the lowest output corresponds NOx. Two– and multistage combustion of fuel is one of the promising methods of regulating the combustion regime and simultaneously a radical reduction of the amount of formed nitrogen oxides. Questions for self-checking: 1. What specific techniques are applied for reducing atmospheric pollution? 2. What is industrial cleaning (or purification)? 3. What is sanitary cleaning? 4. List the methods of air purification from industrial emissions. 5. Explain options for the process of thermal neutralization of gases in furnaces with and without catalysts. 6. Explain why purification of gas emissions by the catalytic method is the best method. Give examples, justify your answer. 7. Describe the successful results of Kazakhstan scientists in the field of catalytic purification of the industrial emissions. Give the examples. 8. Explain the features of air purification from SO2 and H2S emissions. 9. Tell about air purification from CO2. 10. Explain features of gases purification from NOx. 11. Which processes are sources of atmospheric pollution with nitrogen oxides? 12. Explain reduction of emissions of nitrogen oxides to the atmosphere by controlling the combustion process.

255

Chapter 16

SEWAGE OF OIL REFINERIES

16.1. Composition and characteristics of sewage

Modern oil refineries are divided into fuel and fuel-and-oil production with petrochemical production. The main technological processes of oil refining include: 1) preparation of oil, its dehydration and desalting; 2) atmospheric and vacuum distillation; 3) destructive processing (cracking, hydrogenation, isomerization); 4) purification and production of light products; 5) cleaning of oils. All these processes are accompanied by formation of sewage of different composition. The main characteristics of water drains from various installations of standard oil refinery of a fuel and petrochemical profile are presented in tables 26, 27. Table 26 Average volumes of sewage entering the treatment plant of a typical oil refinery

No 1 1 2 3

An object 2 Atmospheric and vacuum crude unit-3 EDP– Atmospheric and vacuum crude unit-6 Atmospheric distillation unit – Viscosity breaking

256

Wastewater volume % of m3/year the total dumping 3 4 64,927 1.2 235,214 4.5 104,032 2

Chapter 16. Sewage of oil refineries: composition and ways of neutralization 1 4 5 6 7 8 9 10 11 12

2 Unit 24/5 35/11-1000 24/2000 Equipment for degreasing tanks Gas-fractionation plant-2 Bituminous installation G-43-107 Chemical water treatment (ChWT) EDP-2 Plant for purification of process condensate and soil13 alkaline waste of oil refining and petrochemicals

3 534,012 27,391 17,169 10,491 9,012 47,405 1,187,292 1,627,499 284,458

4 10.4 0.5 0.3 0.2 0.1 0.9 23.1 31.7 5.5

52,751

1

Average data on wastewater pollution Wastewater Contaminant Petroleum products Hydrogen sulfide Phenol Chlorides Sulphates Suspended substances CСO * BСO5* Ammonium Nitrogen

Table 27

Concentration, mg/dm3 After cleaning Norm for Rate for ponds at the refinery bio-cleaning 7.9 Up to 4 Up to 0,05 3.2 Abs. Abs. 1.3 0.1 Up to 0.01 540 Up to 340 Up to 300 146 Up to 100 7.9 130 Up to 15 64 Up to 3 52 Up to 30 Up to 0.39

Note: *CСO and BСO are one of the important indicators of the level of pollution of sewage waters of enterprises by organic compounds. CСO is an indicator of the chemical consumption of oxygen. BСO is an indicator of biochemical consumption of oxygen.

During the storage and processing of oil and petroleum products, intermediate and by-products, there is an inevitable contamination of the used water by hydrocarbons, solid metal particles and other components (Fig. 36). The main sources of water pollution by oil products are leaks in various connections of technological chains, leaks from

257

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Actual ecological aspects of petrochemical manufactures

the stuffing boxes of pumps, process condensates, atmospheric precipitation, in contact with straits on technological platforms.

Figure 36. Sewage as a result of refinery operation

Let’s consider formation of sewage in the main processes of oil refining. 1. Electro-desalting and dehydration of oil. The greatest amount of water is consumed in the processes of preparation by dehydration and desalination. Oil contains up to 0.5% salts and 2% water. For processing, oil containing no more than 0.0005% salts and not more than 0.1% water is suitable. The process is carried out on the units of the EDP (electric desalting plant). For this aim, the washing water, demulsifier and alkali are injected into the oil; then the mixture is heated and an electrohydrator is introduced, where salt and water are separated. Sewage contains salts, oil and sulfur compounds. 2. Atmospheric and vacuum distillation of oil. Sewage from atmospheric and vacuum distillation of oil contains sulphurous alkaline components, as well as oil. 3. Destructive processing. Sewage from destructive oil processing is formed mainly during condensation of products during cooling (process condensates), they contain a large amount of hydrocarbons.

Chapter 16. Sewage of oil refineries: composition and ways of neutralization

4. Cleaning of petroleum products. Acidic and alkaline cleaning and washing are used to purify petroleum products. Sewage contains acidic wash waters, alkalis and oily neutral waters. 5. Preparation and purification of oils is carried out in the following ways: 1. Deasphalting of oils with propane. 2. Dewaxing of oils in acetone-benzene-toluene. 3. Hydrotreating (from sulfur-containing impurities). In these processes, formation of sewage with severe contamination is possible only in the event of a malfunction of the equipment. Depending on the sources of production, the wastewater is divided into the following groups: 1. Neutral oily wastewater. These include wastewater from condensation, cooling and water washing of petroleum products (except for barometric capacitors of atmospheric and vacuum crude unit), after cleaning the equipment, flushing the floors of the premises, from cooling the bushings of the stuffing boxes of the pumps, drainage water from the trays of technological devices, as well as stormwater from the sites of technological installations. 2. Saline-containing wastewater (effluent from EDP) with a high content of emulsified oil and a high concentration of dissolved salts (mainly sodium chloride). They come from electro-desalination plants and feed streams. These include rainwater from the territory of these objects. The content of salts in the waters of this group depends mainly on the quality of the oils coming in for processing. 3. Sulphide-alkaline wastewater obtained by alkalizing light oil products and liquefied gases. 4. Sour (acid) wastewater from sulfuric acid regeneration plants are formed as a result of poor connections in the equipment, acid losses due to corrosion of the equipment. 5. Hydrogen sulfide-containing sewage generally comes from the barometric condensers of mixture of the atmospheric and vacuum

259

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Actual ecological aspects of petrochemical manufactures

crude units, catalytic cracking, delayed coking, hydrotreating and hydrocracking. In addition to hydrocarbon systems, highly toxic products such as naphthenic acids and their salts, demulsifiers, resins, phenols can be water pollutants. Hydrocarbon contaminants include benzene, toluene, polycyclic compounds and other substances. When developing water treatment technologies, the content of suspensions of solid particles, as well as alkalis, acids and their salts should be taken into account. Substances that pollute the water basin, like air pollutants, are divided into four hazard classes according to the degree of exposure to the human body: 1) extremely dangerous; 2) highly hazardous; 3) moderately dangerous; 4) a little dangerous. The classification is based on the indicators characterizing different degrees of danger to human of chemical compounds polluting water, depending on the toxicity, cumulative action, the ability to cause long-term effects, limiting indicators of harmfulness. Limiting indicators of harmfulness are divided into: – sanitary-toxicological; – general sanitary; – organoleptic with decoding of character of change of organoleptic properties of water. The classes of hazard substances are taken into account: – when selecting compounds that are subject to priority control in water as indicator substances; – when establishing the sequence of water protection measures, for which additional capital investments are required; – when justifying recommendations on the replacement of highly hazardous substances in processes with less dangerous ones; – when determining the order in the development of sensitive methods of analytical determination in water. A specific feature of the enterprises of the oil-processing and petrochemical industry is that sewage is formed, as a rule, not from the

Chapter 16. Sewage of oil refineries: composition and ways of neutralization

isolated productions or units, but it is a set of streams collected from the enterprise in general. In accordance with the currently accepted standards, discharge of industrial wastewater containing oil and oil products must meet the following standard indicators: • when dumping into a reservoir for fishery use, the content of oil products must be not higher than 0.05 mg/l; • when dumping into the system of the city household sewerage, it must be not higher than 4 mg/l (in the long term – to 0.2 mg/l); • for sea dumpings – 25 mg/l. The main pollutants present in the waste waters of oil refineries are petroleum products, suspended solids, salts, organic compounds, phenols, ammonium nitrogen, dissolved hydrogen sulphide. Table 28 presents the averaged data on sewage contamination in several refineries. The data in table 28 prove a significant ecological load on the hydrosphere from oil refining processes. Typical rates of cooling water flow and waste water disposal for refineries without CHP

Water consumption, m3/t Plant profile

Table 28

Amount of sewage discharged into the reservoir, m3/t C����� ondiContaminated tionally Tosewage clean tal sewage

C�������� irculating water

Fresh water

Water losses

Fuel, with a shallow (non-deep) oil refining scheme

16.80

1.31

0.79

1.12

- 

1.12

Fuel, with a deep processing scheme

39.60

1.90

0.76

1.14

-

1.14

Fuel oil, with a shallow (non-deep) oil refining scheme

41.20

2.71

1.10

1.22

0.39

1.61

Fuel oil, with a deep processing scheme

68.50

4.98

2.00

2.52

0.44

2.96

261

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Actual ecological aspects of petrochemical manufactures

The main technological indicator of the quality of waste water discharged by the units of the plant is the content of petroleum products in it. The content of pollutants in the waste water of the refinery is determined by the quality of the processed oil, the technology of its processing and the quality of the final products of production. At the enterprises of transport and storage of oil and oil products, as well as at gas gathering points and gasoline plants, waste water is divided into domestic and industrial. Production waters of oil and gas enterprises are produced in industrial rainwater. These waters are mainly polluted with oil products (400-15,000 mg/l) and mechanical impurities (100-600 mg/l). For their cleaning, mechanical, physico-chemical, chemical and biological cleaning methods are used. The volume and quality of water consumed in the process and the composition of wastewater discharged into open water bodies depend on the technology of production, the type of products obtained, the level of the technical equipment of the enterprise and the intra- and extra-water treatment plants and installations. Sewage petrochemical industries first pass the primary local treatment and then are sent to general sewage treatment plants. In the formation of sewage, a large contribution is made by oil depots, which are designed for receiving, storing and delivering of various petroleum products to consumers and are a complex of technological, energy and auxiliary structures. By destination oil depots can be: – transshipment; – distribution; – transshipment and distribution; – storage bases. The characteristics of sewage of a typical fuel and petrochemical plant are shown in table 29. Identical names are assigned to wastewater treatment plants located on the territories of these bases.

Chapter 16. Sewage of oil refineries: composition and ways of neutralization

Table 29

Characteristics of sewage of a typical oil refinery Concentration of substances, mg/l SusSewage pended Petroleum SulDry Phenol types subproducts phides residue stances Oilcontai700100-300 1,000-8,000 ning 1,500 neutral Salinecontaining 1,00030,000- 30,00010-20 300-800 (efflu10,000 40,000 40,000 ent of EDP) Sulfur6,000800030,000Alka300 12,000 14,000 50,000 line Sour 2,500 (acid) Hydrogen 10,000sulfide4-5 300-400 300-500 15,000 containing

BСOtotal, CСO, рH mg О2/l mgО2/l

150-300 300-500

8001,500

7.27.5

2,000- 7.25,000 8.0

65,000- 100,000- 1395,000 150,000 14 -

-

2-4

2,5003,500

-

5-6

Transshipment oil depots are an intermediate link in the transportation of oil and petroleum products by various types of transport (water, sea, rail, pipeline). The distribution bases are designed to supply the direct consumers of oil and oil products located in the vicinity of these bases. The reloading and distribution oil depots perform the functions of transshipment and distribution at the same time. All bases represent a source of increased danger from the point of view of environmental pollution. In water, most of the petroleum products are in a coarse (drip) state, forming a floating film or a layer. The smaller part is in a finely dispersed state, forming an oil-in-water emulsion. This emulsion is very stable, it does not break down for a long time.

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According to S.L. Zakharov the oily sewage includes: 1. Sludge (from food tanks in which it was formed as a result of settling of watered oil products). 2. Washing (after washing barrels and tanks of rolling stock, closed production areas and drainage overpasses). 3. Contaminated condensate (from steam heaters for dark petroleum products). 4. Water used to seal the oil seals and cool bearings of oil pumps. The volume of sludge depends on the degree of water cut of oil products, which is determined by the conditions of their transportation and storage. Water seeps into the tank through the formed leaks during rains and during transportation in oil tankers, is condensed from the air during storage, falls into the steaming washing of the rolling stock, heating up the dark oil with a sharp steam. The average annual total volume of industrial wastewater (per 1,000 tons of turnover) at oil depots and pumping stations of oil products is given in table 30. Average annual total volume of industrial wastewater (per 1,000 tons of turnover) Enterprise Ttransshipment oil depots The distribution bases Pumping stations of main oil pipelines

Table 30

Volume of sewage, m3 49-198 27-68 7-11

16.2. The processes of sewage treatment. The ways of their neutralization

The processes of sewage treatment can be divided into primary, secondary and tertiary: 1. Primary treatment is removal of solid coarse particles, while in the water remaining colloidal and soluble substances. 2. Secondary treatment is removal of the bulk of organic and inorganic substances from water using special methods. After a secondary

Chapter 16. Sewage of oil refineries: composition and ways of neutralization

treatment, the effluents can be discharged into reservoirs where natural biochemical processes complete the purification. 3. Tertiary processing – after processing sewage is used for obtaining potable water. At refineries and enterprises of petrochemical synthesis, sewage treatment is usually limited to secondary processing. Mechanical wastewater treatment Mechanical treatment of wastewater is used primarily as a preliminary. Mechanical cleaning provides removal of suspended solids from domestic sewage by 60-65%, and from some industrial wastewater by 90-95%. The tasks of mechanical cleaning are to prepare water for physico-chemical and biological purification (table 31). Table 31 Permissible concentration of harmful substances in waste water and the degree of their removal in the process of complete biological purification Harmful substances

1 Oil and oil products Biologically soft (oxidized in biological treatment facilities) anionic Biologically soft (oxidized in biological treatment facilities) non-ionic Intermediate anionic Intermediate non-ionic Formaldehyde Sulphides Copper Nickel Cadmium Chromium (trivalent) Zinc Sulphurous dyes Arsenic

Permissible Degree of concentration of removal harmful during comsubstances in plete biological waste water, mg / l treatment, % 2 3 25 85-90 20 80 50

90

20 20 25 1 0.5 0.5 0.1 2.5 1 25 0.1

60 75 80 99.5 80 50 60 80 70 90 50

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Cyanides Mercury Lead Cobalt

1

2 1.5 0.005 0.1 1

3 50 50

Mechanical treatment of wastewater is to some extent the cheapest method of its cleaning, and therefore the most profound wastewater treatment by mechanical methods is always advisable. At present, great demands are made for cleaning. This leads to creation of highly effective methods of physico-chemical purification, intensification of biological purification processes, development of technological schemes with a combination of mechanical, physicochemical and biological methods of purification and reuse of purified water in technological processes. Mechanical cleaning is carried out for separation of undissolved coarsely dispersed impurities from the wastewater by straining, sedimentation and filtration. To detain large contaminants and partially suspended substances, strain the water through various grids and sieves. Sedimentation is used to separate suspended solids from the waste water, having a greater or lesser density with respect to the density of water. In this case, heavy particles settle, and light particles float up. Filtering is used to trap smaller particles. In the filters for these purposes, filter materials are used in the form of fabrics (mesh), a layer of granular material or chemical materials having a certain porosity. When the wastewater passes through the filter material, suspended matter from the waste water is suspended on its surface or in the pore space. Mechanical cleaning as an independent method is used when clarified water after this method of purification can be used in technological processes of production or discharged into water bodies without disturbing their ecological state. In all other cases, mechanical cleaning serves as the first stage of wastewater treatment.

Chapter 16. Sewage of oil refineries: composition and ways of neutralization

Physico-chemical cleaning In the physicochemical purification a reagent substance (coagulant or flocculant) is introduced into the water to be purified. By reacting chemically with the impurities present in the water, this substance contributes to a fuller isolation of insoluble impurities, colloids and part of the soluble compounds. At the same time, the concentration of harmful substances in wastewater decreases, soluble compounds become insoluble or soluble but harmless, the sewage water reaction changes (neutralization occurs), colored water is provided. Physicochemical purification makes it possible to intensify sharply the mechanical purification of sewage. Depending on the required degree of wastewater treatment, physico-chemical cleaning may be the final or second stage of purification before biological treatment. Chemical Cleaning: the processes of chlorination and ozonization of wastewater suitable for economic use are applied. Biological cleaning Biological purification is based on the vital activity of microorganisms that contribute to the oxidation or reduction of organic substances in sewage in the form of fine suspensions, colloids, in solution and are a source of nutrition for microorganisms, as a result of which the wastewater is purified from contamination. Biological treatment plants can be divided into two main types: 1) facilities in which purification occurs under conditions close to natural; 2) facilities in which purification takes place in artificially created conditions. The first type includes facilities in which the filtered wastewater is filtered through the soil (irrigation and filtration fields) and structures that are water bodies (biological ponds) with running water. In such structures, respiration of microorganisms by oxygen occurs due to direct absorption from the air. In structures of the second type, microorganisms breathe oxygen mainly by diffusing it through the water

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surface (reaeration) or by mechanical aeration. In artificial conditions, biological treatment is used in aerotanks, biofilters and aerofilters. Under these conditions, the purification process occurs more intensively, since better conditions are created for the development of the vital activity of microorganisms. At higher requirements for cleaning, biologically purified water is cleaned additionally. The most widely used as facilities for additional purification were sand filters, mainly twoand multi-layer, as well as contact clarifiers (microfilters are used less often). The concentration of hardly oxidizable substances can be reduced by the sorption method, for example, activated carbon and chemical oxidation or by ozonization. The concentration of salts can be reduced by desalination methods. A total of 0.2-0.3 m3 (oil production) of waste water is spent at the refinery for cleaning 1 ton of processed oil. At modern refineries, discharge and disposal of wastewater is carried out by two main sewerage systems: 1. It includes sewage after cooling equipment, pump oil seals, flushing trays, flushing the floors of industrial premises, after mixing condensers, scrubbers, rainwater, etc. It contains 3 g/l of petroleum products and 100-300 mg/l of suspended solids. 2. It consists of separate networks for collecting and discharging wastewater containing oil, mineral salts, sulfur compounds, alkaline-sulfur and acidic effluents. Here, too, sewage from petrochemical industries: synthetic ethyl alcohol, sulfonol, leaded gasoline are drained. It contains 5 g/l of petroleum products, 0.3-0.5 g/l of suspended matter. Petrochemical production is associated with the formation of technological liquid effluents. These are the products formed in the synthesis of monomers used to produce synthetic resins, fibers, rubbers, plastics, dyes, surfactants and other products. Each of the productions is associated with the formation of sewage of different composition. The main pollutants of waste water are organic substances of target and by-products, oil fractions of adsorption-desorption columns, solid-phase materials.

Chapter 16. Sewage of oil refineries: composition and ways of neutralization

For example, in the production of acetylene, sewage containing phenol, anthracene, naphthalene, soot and other substances are formed; in the production of butadiene – acetone, acetonitrile, alkali, with butane dehydrogenation – chromium and others; in the production of methanol – formic acid, from the synthesis of gas – a resinous residue and a number of other products; in the production of synthetic fatty acids by liquid phase oxidation of paraffin – dicarboxylic acids, aldehydes, ketones, lactones, ethers and other compounds. Sewage containing low-molecular compounds (acids, ketones, ethers, alcohols) are combined into a stream of “acidic” wastewater contaminated with low-molecular fatty acids of the composition C1-C4. They are extracted by azeotropic rectification with isoamyl formate. Sulfate effluents containing 12% Na2SO4 are fed to the sodium sulphite separation facilities. The most commonly used methods of wastewater treatment from pollutants of different nature and aggregate state: 1. For cleaning from suspensions and emulsions – sedimentation, filtration, flotation, clarification, centrifugation, coagulation, electrodeposition. 2. For purification from inorganic compounds – distillation, ion exchange, reverse osmosis, ultrafiltration, cooling methods, electrical methods. 3. For purification from organic substances – extraction, absorption, flotation, ion exchange, reagent methods, biooxidation, liquidphase oxidation, vapor-phase oxidation, ozonation, chlorination, electrochemical oxidation. 4. For cleaning from gases – blowing, heating. 5. For destruction of harmful substances – thermodecomposition. The problem of protecting the water basin from contamination by the waste of oil and gas complexes can be solved by creating treatment facilities, as well as creating in-depth industries – this is an urgent and complex task that can be solved by: 1. Complex processing of raw materials and products. 2. Creation of new anhydrous technological processes.

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3. Reducing the amount and contamination of sewage by improving technological processes and apparatuses, the use of anhydrous raw materials. 4. Implementation of air cooling systems. 5. Use of recycling water supply system. 6. Introduction of new technologies for wastewater treatment. 7. Use of all waters after treatment in recycled water supply. 8. Maintaining of a constant salt composition of circulating water supply. The main direction of reducing the discharge of sewage and their contamination of water bodies is the creation of closed water management systems. A closed water system of an industrial enterprise is a system in which water is used in production many times without treatment or after appropriate treatment, excluding formation of any waste and discharge of waste water into a body of water. A closed system of water management in a territorial industrial complex, district or center is a system that includes the use of surface water, treated industrial and municipal sewage in industrial plants, agricultural irrigation fields for growing crops, for watering forest lands, for maintaining the volume (level) of water reservoirs, excluding formation of any waste and the discharge of sewage into the reservoir. Feeding of closed systems with fresh water is allowed in cases when sewage is not enough purified for completion the losses of water in these systems, also it is used in technological operations in which the purified sewage cannot be used under the terms of technology or hygiene. Fresh water is spent only for drinking and economic and household purposes. The need to create a closed system of industrial water supply is caused by: – water shortage; – exhaustion of the diluting and self-cleaning ability of the water body receiving waste water; – economic benefits of wastewater treatment by the requirements of water protection control.

Chapter 16. Sewage of oil refineries: composition and ways of neutralization

A closed system should ensure rational use of water in all technological processes, maximum recovery of wastewater components, reduction of capital and operating costs, exclusion of environmental pollution. Closed water management systems should be introduced at newly constructed enterprises and at existing ones, subject to reconstruction. The choice of the cleaning method and selection of equipment must be made taking into account: 1) sanitary and technological requirements for the quality of treated waters, taking into account their further use; 2) the amount of waste water; 3) availability of energy and material resources (steam, fuel, compressed air, electric power, reagents, sorbents) necessary for the process of neutralization of the enterprise, as well as the necessary area for the construction of treatment plants; 4) the effectiveness of the process of neutralization. The effectiveness of neutralization of waste water for all methods is determined by a ratio: ɳ = (Cb-Ca)/Cb,

(16)

where Сb and Сa are concentrations of pollution in sewage before and after treatment, kg/m3. If the wastewater treatment from pollution is carried out in succession by several methods, the total degree of purification is: η = 1 – (1 – η1) · (1 – η2) · ... · (1 – ηn),

(17)

where η1, η2, ηn is the degree of wastewater treatment by the first, second and n-th methods. Questions for self-checking: 1. List the main technological refining processes at refineries that pollute wastewater. 2. Tell about the wastewater of a petrochemical (oil refinery) plant.

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Actual ecological aspects of petrochemical manufactures 3. Explain the peculiarity of wastewater treatment in the refining and petrochemical industries. 4. What is the purpose of the processes of electrical desalting and dehydration of oil? 5. Describe the wastewater from the processes of atmospheric and vacuum distillation of oil. 6. Describe the main processes for production and purification of oils based on petroleum and petroleum products. 7. What is technological liquid effluent from oil production? 8. Describe the groups of wastewater resulting from the action of a petrochemical (refinery) plant. 9. List four hazard classes into which substances polluting the water basin and air are divided according to the degree of their impact on the human body. Give examples. 10. What sewage systems are used in modern refineries for wastewater disposal? 11. Describe the primary, secondary, tertiary wastewater treatment processes. 12. What methods are used for wastewater treatment from pollutants of different nature and state of aggregation? 13. What measures are used to solve the problem of protecting the water basin from pollution by oil products? 14. What is the main direction of reducing the discharge of sewage and its contamination of water bodies? 15. What is a closed water system of an industrial enterprise? 16. What is a closed system of water management in a territorial industrial complex, district or center? 17. How is the choice of cleaning method and selection of equipment carried out? What indicators are taken into account? 18. How is the effectiveness of neutralization of waste water for all methods determined? 19. What equation is used to define the total degree of purification?

Chapter 17

PROTECTION OF THE ENVIRONMENT FROM HARMFUL EMISSIONS INTO THE AIR AND WATER BASINS. ENVIRONMENTAL MONITORING

Monitoring is a system of long-term observation, assessment, monitoring and forecasting of the state and change of the objects. At the present time the following methods are used for the elimination of oil pollution of water objects: mechanical, physicochemical, chemical, biological. In order to assess of effectiveness of recovery of land, the reclamation rate is used, reflecting the ratio of recultivated land to the total amount of the areas withdrawn from the turnover. An important direction in land protection is drilling by sectional method. Thus, specific capital investments on each well decrease, the norm of land branch is reduced and the extent of communications decreases. Environmental monitoring is a system for monitoring the environment from anthropogenic pollution associated with human activities. Since natural ecological systems closely interact with each other, this predetermines the complexity and necessity of taking into account various natural and chemical factors when controlling the quality of the environment. To assess the degree of negative impact of pollution, environmental monitoring is carried out as a system for observing and monitoring changes in the composition and functions of various ecological systems. 273

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Environmental monitoring can be carried out on a global, national, regional or local scale. There is background and impact (strong local pollution) monitoring, which involves the implementation of various chemical, physicochemical, physical and biological methods of analysis. The results of analytical definitions and measurements within the framework of environmental monitoring provide information on the pollution of the biosphere by various pollutants unusual for nature, which are collectively called xenobiotics. Environmental monitoring data are used to comprehensively analyze the state of the environment and determine its management strategy, to regulate its quality, to determine the so-called permissible environmental loads on natural systems. These factors can cause geophysical and geochemical changes: possible climate change, acidification of natural waters by acid rain, pollution of the World Ocean and disruption of carbon dioxide balance in it, disruption of the ozone layer. The main requirements for the implementation of environmental monitoring of air, water and soil at the enterprises of oil and gas processing and mining industries are: 1) continuity; 2) systematic character; 3) automation; 4) ensuring improved environmental conditions. Control should not be carried out “occasionally», it should be continuous and “systematic”. For this purpose it is necessary to create automation systems controlling hygienic norms established by the regulatory authorities. Sanitation and hygiene standards include the following activities: 1) the choice of the site for the construction of the enterprise; 2) sizes of sanitary protection zones around the enterprise; 3) requirements for the MPC (MAC) (or temporarily agreed issues), as well as the composition of air and water, ventilation and others. Sanitary and hygienic laboratories monitor dustiness and pollution of the atmosphere in the working area of enterprises. They also

Chapter 17. Control of the environment from harmful emissions into the air ...

track the effects of a number of physical factors (temperature, pressure, wind speed, and others). Hydrometeorological and medical services monitor the quality of atmospheric air and natural waters. However, these measures are not enough to ensure continuous monitoring of the environmental situation at industrial enterprises. To solve this problem, automated systems of environmental control and management are created. Environmental criteria are: 1) concentration of pollutants; 2) the dimensionless point scale – the index of purity. Pollution score is the ratio of the average annual concentration of the pollution to the average daily MAC. Point pollution is the ratio of the average concentration of pollution to the average MAC. The purity index is the ratio of the average daily MAC to the average annual concentration of this pollution. The point pollution and the index of purity can be applied both to an individual type of pollution, and to the generalized types, taking into account synergetic effects (imposing and strengthening of individual effects) or antagonistic interactions. Based on the generalized criteria, a comprehensive assessment can be made. Special models have been developed to evaluate the rate of environmental degradation, taking into account the economic factor. The ability to control the quality of the environment is presented in the block diagram of the monitoring system (Fig. 37).

Figure 37. Block diagram of the monitoring system

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17.1. Environmental Monitoring Instruments and Systems

The main types of automated systems for monitoring air pollution: 1. Industrial systems, including automatic analyzers that control emissions of certain industrial enterprises and the degree of air pollution in areas where enterprises are located. 2. Urban systems designed to measure the level of pollution of the air basin of the city by harmful emissions from industrial enterprises. 3. Regional systems designed for collection and statistical processing of measurement information on atmospheric pollution in a large area. 4. Global monitoring systems, the use of which is associated with the use of space stations. Regional and global monitoring systems use laser methods to measure environmental pollution. The laser-sensing method allows operational control of the degree of air pollution on a large scale. By recording and deciphering the traces of the interaction of laser pulses with atmospheric layers, one can extract information on pressure, density, temperature, concentration of various components of the atmosphere and other parameters. AIS (Automated Information System) is the basis of the organizational structure of monitoring ecological systems. Gas analyzers are devices for determining the qualitative and quantitative composition of gas mixtures contained in the atmosphere. Gas analyzers make it possible to obtain continuous air pollution characteristics and to identify maximum concentrations of impurities that may not be recorded during periodic sampling of air several times a day. Regional instrumental methods of analysis are based on an automated system for monitoring air pollution in an industrial region or in several enterprises. Information comes from automatic gas analyzers installed in various places in the region or around large industrial facilities, sometimes at specific technological installations.

Chapter 17. Control of the environment from harmful emissions into the air ...

Technical Means of Control of Pollution (TMCP) of the air basin are traditionally subdivided by the extent of their automation into: – automatic gas analyzers (instruments measuring the content of pollutants) and/or gas-signaling devices (means of indication of the level of pollution; – non-automated devices or other control devices of steam-air mixes and gas environment (for example, manual express gas-determinants). Among industrial gas analyzers (with the exception of vehicle emission analyzers, which we will not consider here), automatic devices are most commonly used to monitor the air in the working area, as well as emissions from various industries for the following pollutants (arranged in decreasing order of control frequency): 1) carbon monoxide (CO); 2) sulfur dioxide (SO2); 3) nitrogen oxides (NO); 4) nitrogen dioxide (NO2); 5) oxygen (О2); 6) hydrogen sulfide (H2S); 7) carbon dioxide (CO2); 8) amounts of nitrogen oxides (NOx); 9) chlorine (Cl2), ammonia (NH3); 10) organic and other substances. In addition, some industrial gas analyzers are capable of measuring the most important physical indicators of the air environment – temperature (T), pressure (P), gas flow rates, and others in parallel with measuring the concentrations of these substances. Air pollution observations are carried out at: 1) stationary; 2) route; 3) mobile posts. For the purpose of a comprehensive environmental impact assessment, stationary and mobile Environmental Monitoring Stations (EMS) are used.

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Environmental Monitoring Station (EMS) is a station (post) of environmental monitoring of air, an independent block design (blockbox), designed to monitor atmospheric air, working area air and air at the border of the sanitary protection zone. When choosing a station to work in the conditions of the oil field, in addition to economic indicators, it is necessary to take into account the fact that it must meet the following requirements: – autonomy; – ensuring the life of the staff at any time of the year in the area of operation; – patency in off-road conditions; – monitoring and evaluation of a large number of meteorological and environmental parameters of the atmosphere, water basin, soil in the industrial and residential areas; – possibility of maintaining an information database on the basis of the parameters obtained; – have certified equipment and devices that do not require large expenditures for calibration; – have high maintainability. None of the commercially available stations fully meets these requirements. For the convenience and speed of obtaining information about the environmental situation of a large area, including residential industrial facilities, the Incomp-Neft Engineering Company (Russia) has developed and manufactured a specialized vehicle EMS-1 (Environmental Monitoring Station) according to TU 452160-45213414-01. The station is a KAMAZ automobile (a variant was developed on the basis of the Ural motor vehicle), in the back of which a multi-purpose universal modular laboratory is installed, equipped with instruments and equipment for sampling and analysis of water, soil, air, meteorological parameters (Fig. 38). The EMS-1 instrument complex (Fig. 39) consists of separate functional blocks, which can be combined into the following groups: – a set of instruments and equipment for sampling and analysis of air, water, soil samples;

Chapter 17. Control of the environment from harmful emissions into the air ...

– meteorological station (measurement of temperature, air humidity, atmospheric pressure, wind speed and direction); – radiation monitoring unit.

Figure 38. General view of the specialized car EMS-1

The instrumentation of the station allows us to measure and monitor the following parameters: – hydrogen sulfide; – ammonia; – nitrogen dioxide; – carbon monoxide; – sulfur dioxide in the air; – hydrocarbon gas content in air samples; – phenol in water samples; – oil products in water and soil samples; – phosphates, chlorides, sulfides in water samples; – ionic composition and pH of water; – heavy metals in water and soil samples; – meteorological parameters; – gamma radiation intensity.

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Figure 39. Instrument EMS-1 complex

The water quality measurement unit provides measurements of the content of various ingredients in the following ranges: – sulfates 50-300 mg/l; – chlorides 11-3,500 mg/l; – nitrites 0.46-4,600 mg/l; – nitrates 0.31-6,200 mg/l; – oxygen 0-19 mg/l; – carbonates and bicarbonates 5.0-5,000 mg/l; – iron 0.1-1.5 mg/l; – petroleum products 2-500 mg/l. The process of environmental monitoring of the environment is carried out in several stages. First, samples are taken and prepared for analysis. For this, the laboratory is equipped with samplers, sample storage tanks, equipment for preparation for analysis (air cleaning and drying devices, filters and magnetic mixers for water, soil test sieves,

Chapter 17. Control of the environment from harmful emissions into the air ...

chemical dishes and reagents). Then the instrument analysis of the quality of water, air and soil is carried out. The readings of instruments connected to a personal computer are recorded and processed using a specially developed computer program for environmental monitoring. The result of the program is a general picture of the ecological status of the controlled spot or area. The mobility and autonomy of the station makes it possible to assess the state of the ecological situation in areas that are sufficiently distant from each other, and thus assess the situation in fairly large areas. Controlled areas may include cities, rural areas, industrial zones, oil and gas production facilities, a combined heat and power plant, areas surrounding oil and gas pipelines, oil collection and primary preparation (separation) facilities, etc. The EMS-1 station is equipped with an autonomous electric power generator and life support system, including heaters, air conditioning, fans, lighting, furniture, a refrigerator, a microwave oven. The body of the station, inside which the laboratory is located, is made of metal, insulated, with an entrance door and double windows. Questions for self-checking: 1. What are the requirements to carrying out environmental monitoring of the state of air and water at oil-producing enterprises? 2. What activities do sanitary and hygienic norms of environmental control include? 3. What are criteria of quality of the environment at implementation of the automated control and management of the environment? 4. What are the benefits of carrying out automated environmental quality control? 5. List the main types of monitoring. 6. How to carry out monitoring of air pollution in the posts? 7. What is the purpose of the EMS?

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Chapter 18

ECOLOGICAL EXPERTISE OF PETROCHEMICAL TECHNOLOGIES. ECOLOGICAL FORECASTING

18.1. Ecological expertise

Environmental expertise of chemical technologies is an estimate of the low-waste production in comparison with the developed standards or the best available samples. At the same time, the level of economic and ecological danger of the method of production and technological redistribution, and the release of anthropogenic pollutants into the environment, etc. are determined. Methods of environmental assessment of technology are as follows: – material balances and technological calculations; – technological alternative; – forecasting of technological risk; – assessment of the environmental hazards of technology; – registration of environmental consequences of the technology of production of a chemical product. The method of material balances and technological calculations makes it possible to identify sources of emissions and discharges of chemical products, to quantify man-made flows into the environment, to reveal the qualitative composition and aggregate state of pollutants 282

Chapter 18. Ecological expertise of petrochemical technologies. ...

and, in general, all channels of interconnection in the system “technology-environment”. Stages of carrying out environmental impact assessment: – formulation of goals and objectives of the examination; – assessment of sources and directions of negative impact of petrochemical products on the environment and consumption of natural resources; – determination of the compliance of the environmental characteristics of the projected products, technology with the existing norms and rules; – comparative ecological and economic analysis and assessment of the projected and basic version; – assessment of completeness and effectiveness of measures to prevent possible emergencies and elimination of their possible consequences. – assessment of the completeness, reliability and scientific validity of the predictions of the possible impact of new products, technology and technology of chemical compounds on the state of the environment and the use of natural resources; – assessment of the choice of means and methods for controlling the impact of chemical products on the state of the environment and the use of natural resources; – ecological assessment of a way of utilization or elimination of new chemical production after working off of a resource. The result of the environmental assessment is a conclusion of the departmental commission with recommendations on ecological expediency of the development of introduction of this chemical production, or the need for its replacement or further perfecting of the production technology. There are three types of expert indicators: 1) technogenic; 2) ecological and technogenic; 3) ecological and economic.

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Technogenic characteristics contain calculated integrated material and energy balances, including solid waste streams, emissions and discharges with determination by mass and volume, by hazard class, toxicity level, biostability, explosion hazard. All these characteristics are evaluated and compared with the regulatory parameters. Ecological and technogenic characteristics include: – principles and schemes of use of low-waste and non-waste resources and energy-saving technological solutions; – characteristics of systems for cleaning emissions and discharges; – ways of recycling and processing of chemical industry waste; – calculation of possible emergency situations, accompanied by emissions and discharges of harmful substances, taking into account time, mass and volume; – methods and schemes for the elimination of emergency situations and their consequences. 18.1.1. Principles of Environmental Expertise

1. The principle of presumption of a potential environmental hazard of any planned economic and other activities provides that any type of economic activity may lead to negative environmental consequences for the environment. Therefore, the duty of the project customer is to give its environmental justification and to prove the environmental safety of the future production of chemicals. It is necessary to predict: – on the one hand, the impact of a chemical object on the environment; – on the other hand, to justify the permissibility of such an impact and to provide in this connection the necessary environmental measures.

Chapter 18. Ecological expertise of petrochemical technologies. ...

2. The principle of obligation of carrying out the state environmental assessment before the acceptance of the project states that it is necessary to determine: – Whether the proposed activity contradicts the country’s environmental legislation. – Whether the planned chemical activity meets the requirements of normative acts on environmental protection and rational use of natural resources. – Whether the impact of the planned activity of the facility on the environment was sufficiently assessed. – Whether the planned activity of the chemical production facility is acceptable from the point of view of the safety of the environment and the population. – Whether the measures provided by the project for the protection of the environment and the rational use of natural resources are sufficient. The main question that ecological expertise should answer is the possibility of implementing the project (to recommend or not to recommend the project for implementation, to send the project for revision, etc.). The customer is obliged to carry out the state examination of the project prior to the start of its operations. 3. The principle of complexity of environmental impact assessment of economic or other activity and its consequences means that the customer and the developer-appraiser prepare “impact assessment materials” in which they define its influence, scale, the field of distribution, change in the environment, including the remote consequences of implementation of the project. 4. The principle of mandatory registration of environmental safety requirements during the examination provides for the obligation of the participants in the environmental expert process to comply with legal, environmental requirements for the design, placement, construction, operation of chemical expertise. Identify

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non-compliance with environmental quality standards in case of project implementation. 5. The principle of reliability and completeness of information submitted for environmental review obliges the customer of the chemical production project to provide reliable and complete information about the object of expertise to the state expertise, assess its impact on the environment, the current environmental situation in the region, the implementation of the project. 6. The principle of independence of environmental assessment at implementation of the powers in the field of environmental assessment means that nobody has the right to interfere with the work of the expert performed according to requirements of the legislation on environmental assessment, the requirement specification on conducting environmental assessment and the tasks set for the expert by the head of the commission of experts or the head of the group. It is illegal to put pressure upon the expert in any forms. 7. The principle of scientific validity, objectivity and legality of the conclusion of environmental expertise means that the judgments and conclusions contained in the conclusion must be scientifically substantiated. Criteria in this case are not only scientific statements, references to the works of authoritative scientists, but, mainly, the provisions of legislation in the field of environmental protection and nature management. 8. The principle of openness, participation of public organizations, public opinion accounting establishes the duty of subjects of the environmental and expert process to comply with the requirements of the legislation on informing interested parties about the environmental impact assessment, participation of public organizations, and public opinion accounting. Failure to comply with this principle is considered an offense and a reason for bringing the perpetrators to justice.

Chapter 18. Ecological expertise of petrochemical technologies. ...

9. The principle of responsibility of the participants of the environmental impact assessment and interested parties for the organization, carrying out and quality of the environmental impact assessment: in case that they fail to fulfill the requirements of the organization and make the examination, they will be held accountable under the current legislation. The positive conclusion of the environmental impact assessment is one of the mandatory conditions for the start of financing of a petrochemical production project. In the oil refining and petrochemical industry, the normative duration of construction of even a single stage of the enterprise sometimes exceeds a two-year period. In this case, a special permission is required from the relevant legislative bodies for its design and construction. 18.2. Ecological Forecasting

Ecological forecasting is carried out with the purpose of anticipating the results (consequences) of interaction of the planned economic activity, in this case the construction and operation of the projected facility (petrochemical or oil refinery), with environmental components. The process of environmental prediction is carried out in the following sequence: 1. Analysis of environmental parameters: – assessment of natural conditions; – working location of the projected object; – existing technological loads from the other types of economic activity. 2. Determination of the nature of the impact of the projected facility on the environment, taking into account the data on its purpose and specifics of operation, the type and intensity of discharge of pollutants, the parameters of the alleged violation of the natural conditions of the construction area. 3. Establishment of parameters and boundaries of the ecological system and its components that fall under the influence of the object

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(performed when assessing the impact on each component of the environment). 4. Determining the significance of individual natural components interacting with the projected object (depends on the influence of the environment on the object forming external impacts). 5. Development of the forecast of interaction of the projected object with the environment. 6. Verification, i.e., verification of the reliability of the developed forecast. During the process of construction and operation of industrial sites different components of the environment will be exposed. They include: a) violation of the territory and soil layer on the site allocated for construction, deforestation and shrubs; b) violation of the water regime of the territory during excavation and dumping, changing the conditions of surface runoff, and dehydration of the territory due to leaks from water-bearing communications; c) use of surface and groundwater for water supply of the facility; d) pollution of the air basin, territory, water environment by the company’s atmospheric emissions, as well as by suspended substances (dust) lifted by the wind from the surface of disturbed lands, quarries, ash dumps, tailing dumps; e) pollution of water bodies by wastewater discharge; f) radiation contamination of the environment; g) heat emissions, which lead to changes in the thawing time, flood regime, fog formation, etc.; h) the impact of noise, vibration, light, electromagnetic and other physical effects on the adjacent territory; i) activation of dangerous geological processes under the influence of loads from structures, changes in the hydrogeological regime and conditions of surface runoff of the territory; – violation of vegetation and habitat of the animal world. The main factors that reduce the reliability of environmental forecasts are:

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– the lack of precise data on the impact of the projected object on the environment and its response; – the discrepancy between the volumes of the engineering and ecological surveys to be given to the types of impact and parameters of the affected environment; – short-term environmental observations of predictive assessments of the consequences of the proposed activity. 18.2.1. Development of air pollution forecast

Pollution of the air basin during the construction and operation of an industrial enterprise is one of the main factors affecting the environment. Pollution of the air basin is determined by the concentration of pollutants in the ground layer of air with a capacity of 50-100 m. The development of the air pollution forecast is based on the results of calculation of pollutants (dust and gases) from the source of emission, taking into account the prospects for changing the cipher of the structure of the area and the conditions for the emission of pollutants by other industrial and civil-housing objects. To prepare a forecast of air pollution in the area of construction, the following information shall be determined: 1. Characteristics of the physico-geographical, natural climatic conditions of the construction area (locations, climatic and other parameters), which are compiled according to the form of table 37. 2. Data on the projected facility (enterprise capacity, list of the main production facilities, technological parameters and characteristics), prime cost of the main products, the number of employees, names of products, types of energy carriers. 3. The amount of background pollution of the air basin (list of controlled substances, their concentration, data on existing sources of air pollution, etc.) is determined according to the data of the local authorities of KazHydromet.

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4. Characteristics of emission sources of pollutants of the projected facility. They are made in the form of a table. 5. Data on the composition and quantity of emissions of pollutants entering the atmosphere after gas cleaning equipment and from unorganized sources of the facility. 6. Data on the composition and amount of emissions of pollutants entering the atmosphere from other infrastructure facilities in the area in the future. The data are compiled according to the local KazHydromet. Calculations are carried out according to the requirements of the “Methodology for determining emission standards in the environment” in accordance with the Resolution of the Minister of Environmental Protection of the Republic of Kazakhstan. Climatic characteristics of the location of the object Indicator Climatic characteristics Type of climate Temperature mode: average air temperature by month average temperature of the coldest month average maximum temperature of the hottest month duration of the period with positive air temperatures average amount of precipitation per year distribution of precipitation by months Wind mode: recurrence of wind directions average wind speed in the direction (wind rose) maximum wind speed the highest wind speed, the excess of which in a year is 5% Fogs (mists): Aeroclimatic characteristics Complex characteristics congestive (stagnation) situations situations favorable for smog formation

Unit

°С °С °С days mm ξ % m/s m/s m/s

Table 37

The value of the indicator

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18.2.2. Prediction of the state of surface and ground water

To develop a forecast of the impact of the facility on the state of surface and groundwater in the district, the following factors should be determined: – hydrological, hydrogeological and hydraulic characteristics of water bodies used for water supply or water disposal of the projected facility; – the existing level of pollution of surface and groundwater; – the volume of water consumption and wastewater disposal of the projected facility; – location of water intakes and sewage discharge of the facility; – the volume of water consumption of other water users in the region in a given time interval; – quantity, composition and characteristics of wastewater discharged, indicating the main pollutants, their concentration and hazard class; – location and technical characteristics of wastewater indicators of other enterprise facilities affecting the state of the aquatic environment; – changing the parameters of surface runoff of the territory under the impact of the projected facility; – data on the quantity and composition of sewage discharged into rivers and reservoirs of other objects of the district in a given time interval or a prospective level of background pollution of water bodies; – requirements of water authorities to the regime of water use in the region under consideration; – requirements of fish protection bodies to water users of water bodies that are of fishery importance. To make a forecast it is necessary to develop the water management balance (WMB), the perspective needs for water for a given time interval caused by the change of the mode of water use, bound to the operation of an object and change of infrastructure of the area.

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Actual ecological aspects of petrochemical manufactures Questions for self-checking: 1. What is ecological expertise? 2. Describe the methods of environmental assessment of technology. 3. List the stages of carrying out environmental impact assessment. 4. Tell about the three types of expert indicators in conducting environmental impact assessment. 5. What are technogenic characteristics? 6. List the principles of environmental impact assessment. 7. What is the main question that ecological expertise should answer? 8. Tell about environmental forecasting: goal, sequence. 9. Explain the essence of environmental forecasting. 10. List the main factors that reduce the reliability of environmental forecasts. 11. Tell about the environmental forecasting of air pollution. 12. List the characteristics that should be identified to predict air pollution of the construction area. 13. Explain the essence and objectives of predicting the state of surface and groundwater in the area of construction of a petrochemical (refinery) plant.

GLOSSARY

A Absolute humidity of the gas is the amount of water vapor located in the unit volume or mass of the gas (g/m3 or g/kg). Accident is a dangerous technogenic accident creating at the site, territory or waters a threat to life and health of people and leading to the destruction of buildings, equipment and vehicles, disruption of production or transport process, as well as damage to the environment. Events that occur unintentionally or are unexpected, unwanted, unforeseen, and causing damage, injury, etc. Accidents can result in pollutant discharges and physical effects on the environment (e.g., fire and explosions), which are neither expected nor allowed during the course of normal industrial operations. The basic differences between accidents and routine operations, in terms of their potential pressures on the environment and human populations, relate to the following general parameters: the toxicity of discharges, the volume and rate of the release, and flammability and explosiveness. Good planning, management and control of the routine activities is necessary to prevent accidents. Accidental pollution is an unexpected occurrence, losses at a plant or on a transportation route, resulting in a release of a potentially polluting material. ACEA (European Automobile Manufacturers Association) is an organization that develops and monitors the use of quality standards for lubricants for automotive engines in Europe. Acid-base catalysis is a catalytic reaction, where acids or bases are involved as catalysts. In general, this term can refer to both Brönsted and Lewis acids and bases. However, more specific terms for electrophilic and nucleophilic catalysis are also used for Lewis acids and bases. In the case of Brönsted acids and bases, the specific and general acid-base catalyses are distinguished, which are determined by the specific features of the mechanism of the catalytic process. Acidic center is the grouping of atoms in the structure of a macromolecule or on the surface of a solid body, which is capable of attaching a base with transferring it to a conjugated acid. Acidity is the ability of a substance to interact with a base. In this case, the base passes into the conjugate acid. The Act legal (statutory) on protection of the (person) environment is the international or government decision (the convention, the agreement, the pact, the

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Actual ecological aspects of petrochemical manufactures law, the resolution), decisions of local public authorities, the departmental instruction, etc. regulating legal relationship or setting restrictions in the field of protection of the environment surrounding the person. The activation energy, for an elementary chemical transformation, is the minimum energy of the reagents, sufficient to overcome the barrier at the surface of the potential energy that separates the reactants from the products. If the reaction is complex (consisting of several stages), this term usually indicates an effective (apparent) activation energy. Activation of the catalyst is a technological stage which prepares the catalyst for work with reactionary mixture. In some cases it is convenient to carry out activation of the catalyst after its loading into the reactor. At a stage of activation there is a final formation of necessary phase structure of the catalyst, for example, reduction, sulfonation, oxidation, dehydroxylation (removal of water), addition of the activator and other processes are carried out. Activation of chemical reactions is a phenomenon of increasing the rates of chemical reactions in the presence of acids or bases, accompanied by their consumption. Such processes are sometimes called pseudo-catalytic processes. For such reactions, the mechanism of intermediate reaction of the reactants with the acid or base is similar to the true catalytic reaction, however, catalyst regeneration does not occur at the end of the catalytic cycle. Example: hydrolysis of carboxylic acid esters is accelerated in the presence of acid and represents a true catalytic reaction. The hydrolysis of amides of carboxylic acids should be considered as a pseudo-catalytic reaction, since it is also accelerated in the presence of an acid, but at the end of the catalytic cycle, an ammonium ion is formed instead of H+. Activator is a substance which interacts with the catalyst and causes an increase in the speed of the catalytic reaction, but itself isn’t spent. For example, the rate of polymerization of α-olefins on metallocene catalysts increases significantly when methylaluminoxane is added to the system. Active phase – this term has the same meaning as the active component. It is used in those cases when it is required to specify the phase composition of the active component under catalytic process conditions. Example: the melt of potassium pyrosulfonadate is the active phase in the vanadium catalyst for the oxidation of SO2 into SO3. Active component is the substance which is a component of the multicomponent catalyst and direct catalytic transformation. Other components of the catalyst perform support functions, for example, are the carrier or the promotor. Example: for the put (deposited) catalyst of hydrogenation Ni/SiO2, an active component is metal nickel, while silicon oxide is the carrier. Additives are chemicals added to petroleum products in small amounts to improve quality or add special characteristics. They are non-hydrocarbon compounds added to or blended with a product to modify fuel properties (octane, cetane, cold properties, etc.). Examples: oxygenates: alcohols (methanol, ethanol), ethers such as MTBE (methyl tertiary butyl ether), ETBE (ethyl tertiary butyl ether), TAME (tertiary amyl methyl ether); esters (for example, rapeseed or dimethyl ether, etc.); chemical compounds (tetramethyl lead, tetraethyl lead and detergents). It must be remembered that the quantities of ethanol listed in this category should refer to amounts intended for fuel use.

Glossary Adhesion coefficient is the ratio of the number of adsorbed molecules per a unit of time to the frequency of concussions of molecules with the surface of adsorbent. The coefficient of adhesion depends on the filling factor of the surface, temperature, structure of the surface of the adsorbent and other parameters. Adhesive lubricants are lubricants with components that improve adhesion, which do not break from the surfaces by centrifugal forces. Agglomerates are particles of matter obtained by combining smaller particles, for example, associates from primary particles. Aging of the catalyst is a slow and irreversible decrease in the catalytic activity as a result of changes in the structure of the catalyst. Afterburn is the combustion of carbon monoxide (CO) to carbon dioxide (CO); usually in the cyclones of a catalyst regenerator. Aftertreatment system is a system that treats post-combustion exhaust gases prior to tailpipe emission. It differs from emission reduction techniques in the combustion process and allows for greater power from the engine without worrying about increasing emissions. Air is a physical mixture of gases that make up the atmosphere of the Earth, the most important ecological product. From the air plants draw carbon dioxide for photosynthesis, the vast majority of organisms – oxygen for breathing, biological nitrogen fixers – nitrogen. At the surface of the earth, dry and clean air contains 78.9% of nitrogen, 20.95% of oxygen, and 0.03% of carbon dioxide. Other gases account for less than 0.01%. Due to intensive mixing, the air composition in the horizontal and vertical direction up to a height of 80-100 km is constant. Air fin coolers is a radiator-like device used to cool or condense hot hydrocarbons. Air emissions are any substances (gases and particulate matter) emitted into the air from industrial processes or from households, such as carbon monoxide, nitrogen oxide, nitrogen dioxide, sulphur dioxide or any other mixture of particulates and air that are airborne. In many countries, emissions are regulated by countrywide emission standards. These can be either related to specific industries or to general emissions regulations. Air indoors is an atmospheric air, warmed (cooled) and partially filtered through wall coverings and glazed window openings. It is close in composition to the air of populated areas, but it has a higher content of carbon dioxide, lower oxygen and, usually, higher radioactivity, especially in houses of certain types of concrete and silica brick and in the presence of granites in the foundations. To maintain the normal air composition in such houses, the speed of its movement is about 0.1 m / s. The best material for the walls is a tree. Heating systems and kitchens, especially with gas stoves, have an important influence on the air quality of the rooms. Air pollutant is any substance in air that in high enough concentration could harm man, animals, vegetation, or material. Pollutants may include almost any natural or artificial composition of airborne matter capable of being airborne. They may be in the form of solid particles, liquid droplets, gases, or in combination thereof. Generally, they may be: 1) emitted directly from identifiable sources, 2) produced in the air by interaction between two or more primary pollutants, or by reaction with normal atmospheric constituents, with or without photo activation. Air pollution is the discharge of toxic gases and particulate matter introduced into the atmosphere, principally as a result of human activity.

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Actual ecological aspects of petrochemical manufactures Air quality index is a general air pollution index freely available to the public in major West European cities. This daily index, rated from 1 (excellent) to 10 (extremely polluted), takes into account ozone, sulphur dioxide and nitrogen dioxide levels, all of which are toxic for human health and are regulated at the European level. The concentrations close to the warning limit correspond to an index of 4 to 5. However, this daily index, which does give a general idea of the air quality, does not reveal which substance is causing the pollution. A traffic index characterizes the air quality in a dense traffic environment, taking into account the pollutants typical for traffic, nitrogen oxides and carbon monoxide. Any index greater than 6 corresponds to an abnormal situation, index 7 to strong air pollution caused by traffic, and the indices 8, 9 and 10 to increasingly heavy pollution up to an exceptionally high level. Air sweetening is a process in which air or oxygen is used to oxidize lead mercaptides to disulfides instead of using elemental sulfur. Alicyclic hydrocarbon is a compound containing carbon and hydrogen only, which has a cyclic structure (e.g., cyclohexane); also collectively called naphthenes. Aliphatic hydrocarbon is a compound containing carbon and hydrogen only, which has an open-chain structure (e.g., as ethane, butane, octane, butene) or a cyclic structure (e.g., cyclohexane). Alkanes (paraffins, saturated hydrocarbons) are a homologous series of noncyclic hydrocarbons that do not contain double or triple bonds. The simplest alkane is methane, the subsequent terms of the series (propane, butane, pentane, etc.) are obtained by adding to one ethylene one carbon atom – a methyl group. The general formula for the series is CnH2n+2. Alkenes (unsaturated hydrocarbons, olefins) is a homologous series of non-cyclic hydrocarbons containing double bonds. The simplest member of the series contains two carbon atoms – ethylene. Next followed by propylene, butylenes, etc. The general formula for the series is CnH2n. Alternative fuels are fuel types (compressed and liquefied gas, biogas, generator gas, biomass processing products, water-coal fuel, etc.), the use of which reduces or replaces the consumption of energy resources of more expensive and scarce species. Alumina (A12O3) is oxide of aluminium and it is used in separation methods as an adsorbent and in refining as a catalyst. Aniline point is the temperature, usually expressed in ºF, above which equal volumes of a petroleum product are completely miscible; a qualitative indication of the relative proportions of paraffins in a petroleum product which are miscible with aniline only at higher temperatures; a high aniline point indicates low aromatics. Antiknock is resistance to detonation or pinging in spark-ignition engines. Antiknock agent is a chemical compound such as tetraethyl lead which, when added in a small amount to the fuel charge of an internal-combustion engine, tends to reduce knocking. Antistripping agent is an additive used in an asphaltic binder to overcome the natural affinity of an aggregate for water instead of asphalt. Anthropogenic landscape is the natural landscape transformed by human activity. Anthropogenous pollution is pollution resulting from people’s activities, including their direct or indirect impact on the intensity of natural pollution.

Glossary Anthropogenic factor is an environmental factor associated with human exposure to the environment: pollution, depletion of resources, reduction of animal and plant species. API Gravity is an arbitrary scale expressing the density of petroleum products. Apparent density is the density of a solid porous substance, which is calculated as the ratio of the mass of the particle to its volume. Since part of this volume falls on the pores inside the particle, the apparent density of the porous substance is less than its true density. Aromatic hydrocarbons are organic compounds containing a cycle with conjugated double bonds in their structure. In the petrochemical industry, this name usually involves benzene, toluene and xylenes (ortho-, meta– and para-). Aromatics are organic compounds with one or more benzene rings. Aromatization is the conversion of nonaromatic hydrocarbons into aromatic hydrocarbons by: (1) rearrangement of aliphatic (noncyclic) hydrocarbons into aromatic ring structures; (2) dehydrogenation of alicyclic hydrocarbons (naphthenes). ART process is a process for increasing the production of liquid fuels without hydrocracking. Asphalt is a nonvolatile product obtained by distillation and treatment of an asphaltic crude oil with liquid propane or liquid butane; usually consists of asphaltenes, resins, and gas oil; a manufactured product. Asphaltene is a fraction of petroleum, heavy oil, or bitumen that is precipitated when a large excess (40 volumes) of a low-boiling liquid hydrocarbon (e.g., pentane or heptane) is added to (1 volume) of the feedstock; usually a dark brown to black amorphous solid that does not melt prior to decomposition and is soluble in benzene or aromatic naphtha or other chlorinated hydrocarbon solvents. Asphaltenes are the asphalt compounds soluble in carbon disulfide but insoluble in paraffin naphthas. They are the most high-molecular components of oil. Associated petroleum gas, APG is an oil product. In reservoir conditions, it is dissolved in oil and released when the fossil is extracted to the surface. The composition of associated gas varies greatly, but its main component is methane, as well as a certain amount of ethane, pentane and butanes, etc. ATF liquid is a special gear oil that has a liquid consistency and has a mineral or synthetic base. It is intended for cars operating on “automation”. ATF transmission fluid is responsible for performing many functions, for example: the smooth operation of the gearbox – its control and management; cooling and proper lubrication of parts that can be rubbed; transmission of torque, which through the torque converter passes from the motor to the box; friction disco operation Atmosphere is a gaseous shell of the Earth, held by gravity and taking part in its rotation, consisting of a mixture of different gases, extending for approximately 100 km (there is no strict upper boundary of the atmosphere). Dry atmospheric air consists of nitrogen (78.0 9%), oxygen (20.93%), argon (0.93%), carbon dioxide (0.03%), hydrogen, helium and other gases. The modern atmosphere is largely the result of the activity of living matter. Complete renewal of oxygen by living matter takes place over 5,200-5,800 years. All its mass is assimilated by living organisms for 2,000 years, all СО2 – for 300-400 years. Under the influence of economic human activity in the atmo-

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Actual ecological aspects of petrochemical manufactures sphere there are negative changes – an increase in the amount of greenhouse gases, the destruction of the ozone layer. This leads to negative consequences for the biosphere (warming of the climate, acid rains, etc.). Atmospheric air is a vital component of the natural environment, which is a natural mixture of atmospheric gases outside the residential, industrial and other premises. Audit of environmental management systems is a systematic and documented process for verifying objectively obtained and evaluated audit data to determine whether an organization’s environmental management system (or nonconformity) is in compliance with the audit criteria for such a system, and to communicate to the client the results obtained during this process. Auditor in the field of ecology (auditor-ecologist) is a person having the appropriate qualifications and a certificate for conducting environmental audits. Aviation gasoline is any of the special grades of gasoline suitable for use in certain airplane engines. It is motor spirit prepared especially for aviation piston engines, with an octane number suited to the engine, a freezing point of -60 °C and a distillation range usually within the limits of 30 °C and 180 °C. B Barrel is the unit of measurement of liquids in the petroleum industry; equivalent to 42 U.S. standard gallons or 33.6 imperial gallons. It is a unit of measure for volume equal to ≈ 159 l. Barium complex, lubrication is a grease based on barium complex and mineral and/or synthetic base oils, has the property of watertightness and good shear stability, often has a narrow operating temperature range. Base oils are light oil products or synthetic hydrocarbons, used together with additives for production of lubricating oils – motor and transmission oils and ATF liquids. Battery is a series of stills or other refinery equipment operated as a unit. Bentonite is montmorillonite (a magnesium-aluminum silicate); used as a treating agent. Benzo(a)pyrene is a compound from the group of polycyclic aromatic hydrocarbons, a widely spread carcinogen substance. It is present in gaseous industrial wastes, in automobile exhausts, in tobacco smoke, in food combustion products. Ferrous metallurgy accounts for up to 40%, heat-power engineering – 26%, the chemical industry – 16% of benzene(a)pyrene, supplied to the environment. Benzene is an unsaturated, a colorless, six-carbon ring, basic aromatic liquid compound (C6H6). BET is the method of determination of specific surface area of solid bodies based on the model of physical adsorption of molecules of gases (nitrogen, argon, etc.) using the accepted value of molecular cross section. The method has received the name by the names of three scientists (S. Brunauer, P. Emmett, E. Teller), who developed the corresponding model for polymolecular adsorption. Despite some shortcomings in the theoretical description, this method is widely used as a standard technique for determining the surface area of catalysts and adsorbents.

Glossary Bitumen is a solid, semi-solid or viscous hydrocarbon with a colloidal structure, brown to black in colour, obtained as a residue in the distillation of crude oil, by vacuum distillation of oil residues from atmospheric distillation. Bitumen is often referred to as asphalt and is primarily used for construction of roads and for roofing material. This category includes fluidised and cut back bitumen. Bituminous is containing bitumen or constituting the source of bitumen. Bituminous sand is a formation in which the bituminous material (see Bitumen) is found as a filling in veins and fissures in fractured rocks or impregnating relatively shallow sand, sandstone, and limestone strata; a sandstone reservoir that is impregnated with a heavy, viscous black petroleum-like material that cannot be retrieved through a well by conventional production techniques. Blending is the process of mixing two or more petroleum products with different properties to produce a finished product with desired characteristics. A block (honeycomb) catalyst is a heterogeneous catalyst in which a carrier is used in the form of a monolithic block. Usually the block has a set of the parallel not crossed channels and is manufactured of ceramic silicate or metal materials. The active component is applied to the surface of the channels. The block catalyst is used in such processes where a large pressure drop is undesirable, for example, in the neutralization of exhaust gases in automobiles. Boiling range is the range of temperature usually determined at atmospheric pressure in standard laboratory over which the boiling (or distillation) of a hydrocarbon liquid commences, proceeds, and finishes. Broad (wide) fraction of light hydrocarbons (BFLH or WFLH) is a product of processing of associated petroleum or natural gas. It is a mixture of volatile hydrocarbons with a number of carbon atoms from 2 to 5 and valuable petrochemical raw materials. Bulk density is the density of a solid-phase material calculated as a ratio of the mass of the sample to the volume occupied by the sample. At the same time, the volume considers the free space which is available in particles and between particles. Thus, bulk density depends both on porosity of individual particles, and on the density of their packing, which in turn depends on the geometrical form of particles (powder, granules, tablets, etc.). Butane dehydrogenation is a process of removing hydrogen from butane to produce butenes and, on occasion, butadiene. Butane vapor-phase isomerization is a process for isomerizing n-butane to isobutene using aluminum chloride catalyst on a granular alumina support and with hydrogen chloride as a promoter. Butane-butylene fraction (BBP) is a gaseous product of a catalytic cracking process containing normal (unbranched) alkanes and alkenes with 4 carbon atoms. C C1, C2, C3, C4, C5 fractions is a common way of representing fractions containing a preponderance of hydrocarbons having 1, 2, 3, 4, or 5 carbon atoms, respectively, and without reference to hydrocarbon type. A car is a common vehicle, the most important factor in the formation of an urbanized territory. The number of cars, especially in megacities, is very large and growing.

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Actual ecological aspects of petrochemical manufactures Carbene is the pentane– or heptane-insoluble material that is insoluble in benzene or toluene but which is soluble in carbon disulfide (or pyridine); a type of rifle used for hunting bison. Carboid is the pentane– or heptane-insoluble material that is insoluble in benzene or toluene and which is also insoluble in carbon disulfide (or pyridine). Carbon residue is the amount of carbonaceous residue remaining after thermal decomposition of petroleum, a petroleum fraction, or a petroleum product in a limited amount of air; also called the coke– or carbon-forming propensity. Carbonate washing is processing using a mild alkali (e.g., potassium carbonate) process for emission control by the removal of acid gases from gas streams. Carbonization is formation of coke on the surface of heterogeneous catalysts. Deposits of coke block the surface of the catalyst therefore its activity can significantly decrease and change selectivity of the catalyst. It is one of the main reasons for the deactivation of catalysts used in refining processes (cracking, reforming, dehydrogenation, etc.). It is the removal of all lighter distillable hydrocarbons that leave a residue of carbon in the bottom of units or as buildup or deposits on equipment and catalysts. Carrier is a solid phase component in the deposited (supported) catalyst, on the surface of which the active component is located. The main functions of the carrier are maintenance of an active component in a disperse state, creation of a porous system, ensuring mechanical durability of granules of the catalyst. Simple and complex oxides, and also materials on the basis of carbon are widely used as carriers. As a rule, the carrier in pure form doesn’t show catalytic activity in relation to reagents and is an inert substance. But many examples when the carrier enters into chemical interaction with the reactionary medium, or with an active component are known. Catalysis is the phenomenon of initiation of chemical reactions or change of their speed under the influence of substances – catalysts, which repeatedly enter into intermediate chemical interaction with the participants of the reaction and restore the structure after each cycle of intermediate interactions. At the same time, the catalyst doesn’t displace chemical balance of reactions. Catalyst is a substance that changes the rate of chemical reactions without shifting their chemical equilibrium, which repeatedly enters into an intermediate chemical interaction with reagents and regenerates its chemical composition after each cycle of such interactions. An important feature is that the catalyst is regenerated in each catalytic cycle, which allows conversion of large amounts of reagents in the presence of a relatively small amount of catalyst. As a rule, for each chemical reaction it is required to select a specific catalyst. Practical application as catalysts is found by extremely different substances – from solutions of acids and complexes of metals to complex solid-phase multicomponent compounds of strictly specified composition and a structure. Catalyst durability is ability of particles of the solid-phase catalyst to maintain mechanical loadings. There are various experimental techniques for determination of durability (for example, durability on attrition, durability on crush). For commercial catalysts high durability allows us to minimize losses during catalytic process, as well as during transportation the catalyst and its loading in the reactor. Catalyst plugging is deposition of carbon (coke) or metal contaminants that decreases flow through the catalyst bed.

Glossary Catalyst poisoning is deposition of carbon (coke) or metal contaminants that makes the catalyst nonfunctional. Catalyst selectivity is a relative activity of the catalyst with respect to a particular compound in a mixture, or the relative rate in competing reactions of a single reactant. Catalyst productivity is the amount of product produced per unit time, referred to the mass or volume of the catalyst. Catalyst stripping is the introduction of steam, at a point where spent catalyst leaves the reactor, in order to strip, i.e., remove deposits retained on the catalyst. Catalytic activity is the rate of a chemical reaction, referred to the number of active catalyst centers or to a unit of mass or volume of the catalyst. The activity of the catalyst is determined by the nature and strength of the chemical bonds that are formed when reactants and reaction intermediates are bound to the catalyst. For a correct measurement of the catalytic activity it is necessary to exclude the impact of mass and heat transfer. The catalytic center is the center in which catalytic chemical transformations occur. If the number of the catalytic centers is unknown, for example, in case of a heterogeneous photocatalysis, for determination of specific parameters BET surface measured on nitrogen adsorption is used. Catalytic combustion is a technology developed to produce thermal energy by oxidizing combustible compounds with oxygen in the presence of a catalyst. In the presence of catalysts, oxidation occurs at lower temperatures (without open flame). Multicomponent catalysts containing Cu, Cr, Pd, Mn and other components are used. Catalytic combustion is used in catalytic heat generators (CHG). The catalytic converter (neutralizer) of exhaust gases of the car engine is the device for neutralization of the exhaust gases of the car engine by a method of catalytic action. It is a catalyst that provides removal of a number of harmful substances from the exhaust gases in the internal combustion engines. The main catalytic processes are oxidation of CO, post-combustion of hydrocarbons to CO2 and reduction of nitrogen oxides. The most suitable are noble metal catalysts (Pt). The neutralization process is complicated due to temperature fluctuations in the exhaust gases (from 200 to 1,000°C) and changes in the composition of the gas mixture (from oxidizing with excess oxygen to reducing with oxygen deficiency). Catalytic cracking is a secondary process of oil refining (process of conversion), which consists in splitting of long hydrocarbonic molecules into shorter ones. It is the process of breaking up heavier hydrocarbon molecules into lighter hydrocarbon fractions by use of heat and catalysts and a source of petrochemical raw materials, such as propane-propylene fraction. Catalytic reforming is a secondary process of oil refining, the essence of which is the conversion of hydrocarbon chains into aromatic compounds – components of fuels and petrochemical raw materials. Catalytic cycle is a system of elementary reactions with participation of the catalyst at which the sequence is closed, a cyclic process of binding and regeneration of the catalyst occurs and the conversion of the starting materials to the products. An important feature is that after completion of the catalytic cycle, the catalyst passes to the initial chemical state and the catalytic cycle can be repeated many times with the same catalyst.

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Actual ecological aspects of petrochemical manufactures Catalytic erosion is the destruction of the catalyst in the dendritic mechanism of coke formation. Separate components of the catalyst are mechanically separated and carried away with the growth of primary dendrites, which can lead to the complete destruction of the catalyst. The catalytic reaction is a chemical reaction proceeding through a sequence of stages forming a catalytic cycle. The catalytic route of the reaction is proved by the fact that the catalytic cycle can be realized several times (the number of revolutions exceeds unity). Currently, more than 80% of all industrial chemical processes are carried out using catalytic reactions. Catalytic poison is a substance that forms strong chemical bonds (usually covalent) with atoms and ions entering the active sites of the catalyst to form catalytically inactive centers and, thus, leads to deactivation of the catalyst. In most cases, the catalytic activity and/or selectivity cannot be restored without a significant change in the reaction conditions. Special regeneration procedures are required, and most often the characteristics can only be partially recovered. The catalytic poison may be present as an impurity in a mixture of reagents, or it may enter the catalyst during the preparation stage. Typical poisons are sulfur and arsenic compounds, and also the compounds of transition metals contained in raw materials can act as catalytic poisons. CHP is a combined heat and power plant, a system in which steam produced in a power station as a byproduct of electricity generation is used to heat nearby buildings. Clay is silicate minerals that also usually contain aluminum and have particle sizes are less than 0.002 micron; used in separation methods as an adsorbent and in refining as a catalyst. Clay refining is a treating process in which vaporized gasoline or other light petroleum product is passed through a bed of granular clay such as fuller’s earth. Clay regeneration is a process in which the spent coarse-grained adsorbent clays from percolation processes are cleaned for reuse by de-oiling them with naphtha, steaming out the excess naphtha, and then roasting in a stream of air to remove carbonaceous matter. Clay wash is a light oil, such as kerosene (kerosine) or naphtha, used to clean fuller’s earth after using it in a filter. The Clean Development Mechanism (CDM) is the cooperation mechanism created in the framework of the Kyoto Protocol, which opens potential opportunities for the help to developing countries in ensuring sustainable development due to support the ecologically favorable investments of the governments and businesses of industrially developed countries. Closed pores are pores that do not communicate with the outer surface of the particle. Molecules from the surrounding space cannot penetrate into the closed pores, therefore, such pores cannot participate in adsorption and catalysis. Closed system of water management in a territorial industrial complex, district or center is a system that includes the use of surface water, treated industrial and municipal sewage in industrial plants, agricultural irrigation fields for growing crops, for watering forest lands, for maintaining the volume (level) of water reservoirs, excluding the formation of any waste and the discharge of sewage into the reservoir. Closed water system of an industrial enterprise is a system in which water is used in production many times without treatment or after appropriate treatment, excluding formation of any waste and discharge of waste water into the body of water.

Glossary Coagulation is the process of combining (cohesion) of small particles in a dispersed system with the formation of larger particles. Example: as a result of coagulation, the sol passes into the suspension. Coalescence is the process of merging droplets or gas bubbles in disperse systems. Coke means the condensed aromatic hydrocarbons whose structure approximates to graphite. The formation of coke on the surface of catalysts is a harmful byproduct of hydrocarbon processing. Coking is formation of coke on the surface of heterogeneous catalysts. Deposits of coke block the surface of the catalyst therefore its activity can significantly decrease and change selectivity of the catalyst. Coking is one of the main reasons for the deactivation of catalysts used in refining processes (cracking, reforming, dehydrogenation, etc.). A colloidal solution is a dispersed system occupying an intermediate position between true solutions and coarsely dispersed systems. The particles of the dispersed phase in the colloidal solution have a size from 1 to 100 nm. Combustible gases are the natural gases having ability to burn. They usually consist of gaseous hydrocarbons (methane, ethane, etc.) and are satellites of oil, although purely gas fields are also known. If combustible gas contains a significant amount of vapors of natural gasoline (gasoline), such gas is called fat, at very small content of natural gasoline or at its absence gas is called dry. B. Comenar’ laws can be expressed in the following laconic formulas: • everything is connected with everything (reflects property of generality of ties); • everything has to disappear somewhere (option of conservation laws); • nature knows better (human knowledge of natural processes is limited); • nothing is given by a gift, nothing is free (the use of any resource needs to be compensated). Compounding is mixing of several components in a certain ratio to obtain a petroleum product of a given quality. The concept of sustainable development proclaimed by the international community is a conceptual base for the development of international and national policy in the field of environmental management and environmental protection considering close interrelation of the nature protection activity with economy and the social sphere now. Condensate is a natural mixture of mainly light hydrocarbon compounds that are in a dissolved gas and are converted into a liquid phase, with a decrease in pressure, below the condensing pressure. Condensation is transition of a substance from the gaseous state into a liquid or solid phase. In case of a disperse system this term designates formation of a heterogeneous system from a homogeneous one as a result of association of molecules, atoms or ions in units. Contaminant is a substance that causes deviation from the normal composition of the environment. Conversion is the ratio of the amount of reagent converted into products to the total amount of reagent fed to the reactor inlet. At the same time the amount of reagent can be measured in various units (mol number, weight, etc.). Cracking is the process of breaking C-C bonds in a hydrocarbon molecule to form fragments with a lower molecular mass. This is one of the most important pro-

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Actual ecological aspects of petrochemical manufactures cesses in oil refining, used to convert high-boiling oil fractions to components with a higher octane number. There are catalytic cracking and thermal cracking. Crude condensate is a liquid which is released from the gas directly in the field separators at the separation pressure and temperature. Crude oil is a naturally occurring mixture of hydrocarbons that usually includes small quantities of sulfur, nitrogen, and oxygen derivatives of hydrocarbons as well as trace metals. It exists in the liquid phase under normal surface temperature and pressure and its physical characteristics (density, viscosity, etc.) are highly variable. Crystallization is a process of formation of a crystal phase of solution, steam or other solid phase, usually by a decrease in temperature or evaporation of solvent. Cumene is a colorless liquid [C6H5CH(CH3)2] used as an aviation gasoline blending component and as an intermediate in the manufacture of chemicals. Curing (vulcanizing, vulcanization) is the process of rubber formation from rubber under the influence of vulcanizing agents, for example, sulfur. It consists in the cross-linking of polymer chains of rubber with each other into a single spatial grid. Cyclone is a device for extracting dust from industrial waste gases. It is in the form of an inverted cone into which the contaminated gas enters tangentially from the top; the gas is propelled down a helical pathway, and the dust particles are deposited by means of centrifugal force onto the wall of the scrubber. D Deactivation of the catalyst is a partial reduction or complete loss of catalytic activity during operation of the catalyst. This term unites a fairly wide range of different processes and phenomena responsible for reducing catalytic activity. The most frequent reasons for the deactivation of catalysts are the change in the chemical composition of the catalyst under the conditions of the reaction medium, volatility of the active component, interaction of the active component with the carrier to form new phases, change in the dispersion of the active component, poisoning, crystallization, sintering, coking and catalyst contamination. Dealkylation is the removal of an alkyl group from aromatic compounds. Deasphaltened oil is the fraction of petroleum after the asphaltenes have been removed using liquid hydrocarbons such as n-pentane and n-heptane. Deasphaltening is a removal of a solid powdery asphaltene fraction from petroleum by the addition of the low-boiling liquid hydrocarbons such as n-pentane or n-heptane under ambient conditions. Deasphalting is a process of removing asphaltic materials from reduced crude using liquid propane to dissolve nonasphaltic compounds. Debutanization is distillation to separate butane and lighter components from higher boiling components. Debutanizer is a fractionating column used to remove butane and lighter components from liquid streams. De-ethanization is distillation to separate ethane and lighter components from propane and higher-boiling components; also called de-ethanation. De-ethanizer is a fractionating column designed to remove ethane and gases from heavier hydrocarbons.

Glossary Degradation of the environment (from the French degradation – reduction, backward movement, deterioration, decline in quality): 1) general deterioration of the natural environment, joint deterioration of the natural and social environments (landscape degradation, soil degradation, etc.); 2) deterioration of the natural environment of human life as a result of natural phenomena (for example, volcanic eruptions, floods) or as a result of economic activities of man (destruction of natural ecosystems, pollution of natural waters, etc.). Degradation of the environment occurs due to the destruction or disturbance of the bonds that ensure the exchange of substances and energy within nature, between nature and man, which is caused by the activity of man, carried out without taking into account the laws of nature development. Dehydrogenation is the process of splitting off a hydrogen molecule from an organic compound. It is removal of hydrogen from a chemical compound; for example, removal of two hydrogen atoms from butane to make butene(s) as well as removal of additional hydrogen to produce butadiene. In industry it is used to convert ethane, propane, and butane into olefins (ethylene, propylene, and butenes). Dehydrocyclization is any process by which both dehydrogenation and cyclization reactions occur. Demethanization is the process of distillation in which methane is separated from the higher boiling components. The deposited catalyst is a heterogeneous catalyst in which the finely divided particles of the active component are located on the surface of the carrier. Example: in the Pt/Al2O3 hydrogenation catalyst, the dispersed particles of metallic platinum (the active component) are deposited on the surface of alumina (carrier). The deposition is a step of preparing the supported (put) catalysts, as a result of which the precursor of the active component passes from the solution or from the gas phase to the surface of the solid support. Different methods of application have their own names (for example, impregnation, deposition-precipitation, etc.). Desulfurization is a chemical treatment to remove sulfur or sulfur compounds from hydrocarbons. Detergent oil is a lubricating oil possessing special sludge-dispersing properties. Detoxication means: 1) destruction and neutralization of various toxic substances by chemical, physical or biological methods; 2) the process of neutralization within the biological system of harmful substances that have entered it. Detoxication of waste means their release from harmful (toxic) components on specialized installations. Dewaxing is the removal of wax from petroleum products (usually lubricating oils and distillate fuels) by solvent absorption, chilling, and filtering. Diesel engine (in common parlance – “diesel”) is a reciprocating internal combustion engine that operates on the principle of spontaneous ignition of sputtered fuel from the action of air heated by compression. It is used mainly on ships, diesel locomotives, buses and trucks, tractors, diesel power stations, and by the end of the 20th century it became common on passenger cars. The diesel engine is named by its inventor. The first compression-ignition engine was created by Rudolf Diesel in 1897.

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Actual ecological aspects of petrochemical manufactures The range of fuel for diesel engines is very wide, it includes all fractions of oil refining from kerosene to fuel oil and a number of products of natural origin – rapeseed oil, frying oil, palm oil and many others. The diesel engine can with some success work on crude oil. Diesel fuel is fuel used for internal combustion in diesel engines; usually that fraction which distills after kerosene. Differential selectivity is the ratio of the rate of formation of the target product to the total rate of consumption of the reagent due to all reactions. Unlike integral selectivity, differential selectivity depends only on the temperature and composition of the reaction mixture, and does not depend on the type of reactor. Differential mode of the reactor is the mode of operation of the ideal displacement reactor, in which the conversion of the initial reactants at the outlet from the reactor remains low. Under such conditions, it can be assumed that the entire volume of the catalyst interacts with the reaction mixture in which the concentration of the reactants is the same. Diseases ecological is disruption of the normal life of the human body, caused by negative changes in environmental factors. Examples of such diseases are “ita-ita”, “Minamata”, “Yusho”, etc. The disease “ita-ita” (literally translated – “oh-oh”) is the result of poisoning by cadmium, known from 1955, from sewage waters of the Japanese concern “Mitsui” in the irrigation system of rice fields. Eating poisoned rice caused apathy, pain in different parts of the body, damage to kidneys and softening of bones. The disease “Minamata” is poisoning with methylmercury. The name of the disease is connected with Minamata Bay (Japan), where in the 1950s mercury-containing wastewater from the Chisso campaign was discharged. Mercury accumulated in fish, which was eaten by local people. The consequence was severe damage to the nervous system in the population, mental and physiological anomalies in every third newborn. The disease “Yusho” is poisoning with polychlorinated biphenyls (PCBs). In 1968, in Japan, in the process of cleaning rice oil, PCBs got into the oil, which resulted in poisoning of the population, accompanied by loss of weight, development of malignant tumors, liver, spleen, kidneys, skin darkening. The dispersed phase is a finely divided substance in the composition of a dispersed system. Dispersing is crushing or grinding of macroscopic particles of matter. Dispersion is a quantity that is equal to the ratio of the number of surface atoms to the total number of atoms in the particle. Dispersion is inversely proportional to the particle size. The higher the dispersion of the particles, the smaller their size and, hence, the higher the fraction of surface atoms. The dispersion medium is a part of the disperse system, in the volume of which the disperse phase is distributed. The dispersion system is a heterogeneous system containing a finely divided substance (dispersed phase), which is distributed in the volume of some other substance and does not mix with it (dispersion medium). Distillation is a process of physical separation of oil and gas into fractions (components), different from each other and from the initial mixture by temperature limits (or temperature) of boiling. By way of the process a simple and a complex distillation are distinguished.

Glossary Doping is the formation of a solid solution when small amounts of foreign atoms are added to the crystal lattice of a nonmetallic catalyst. The term is generally applied to catalysts that are semiconductors. Doping changes the electronic properties of the catalyst, which can affect the rate of catalytic conversion. Dry gas is natural gas with so little natural gas liquids that it is nearly all methane with some ethane. Drying is the stage of preparation of catalysts, as a result of which excess solvent is removed from the catalyst. Typically, drying takes place at elevated temperatures, but without any chemical transformation in the catalyst structure. Dry stripped gas (DSG) is a product of processing associated petroleum or natural gas. It is a methane with minor impurities of other hydrocarbons. It is used mainly as a fuel. E Eco-Industrial Park (EIP) is an association of producers of goods and services wishing to improve the economic and environmental situation through joint management of natural resources (energy, water and materials) and the environment. Working together, manufacturers hope to get a better collective effect than they would have individually. The goal of Eco-Industrial Park is to improve the economic status of participating producers and to reduce environmental pollution. Ecology is a synthetic science, which comprises three main directions: • general ecology or bioecology studies the relationship of living systems with the environment and with each other; • geoecology studies the dynamics of geospheres, including the biosphere, their interaction and geophysical conditions of life; • applied ecology studies aspects of engineering and social protection of human environment. The term “ecology” was proposed by E. Haeckel in 1886 and originally designated one of the branches of biology, which studies the interrelationship of the species of living beings and their habitat. Ecology basic laws, which are directly related to the geoecology of subsoil use, include: • limitation of natural resources and a decline in natural and resource potential; • internal dynamic balance of ecological systems; • decrease in energy efficiency of subsoil use: optimality or rationality in geoecology. Ecology task as a science is to study human activity in the environment, as well as to study the processes of restoring the environment disturbed by man. Ecology is also a scientific basis for the rational use of natural resources, including minerals. Electrical Desalting Plants (EDP) are plants that are necessary to remove salt from crude oil in order to avoid corrosion of oil refining technology, increase its service life, reduce the cost of maintenance and repair of chemical reactors. EDP is the first installation through which the oil entering the plant must pass.

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Actual ecological aspects of petrochemical manufactures Effective density is the density of solid phase catalysts, determined on the basis of the volume of liquid that is displaced by the sample when it is placed in this liquid. The effective density values can differ significantly for different liquids due to the fact that a different degree of penetration of liquids into the pores of the catalyst is observed. The effective pore size is the diameter of the maximum circumference, which can be inscribed in a flat pore cross section. In this case, the plane section of the pore can have an arbitrary geometric shape. Efficiency of the catalyst is the number of molecules of the formed products referred to one molecule of the active centers of the catalyst. It is the cumulative characteristic of catalytic properties considering activity, selectivity and period of operation of the catalyst without loss of catalytic activity. Electrophilic catalysis is a catalytic reaction in which the catalyst is a Lewis acid. Example: Friedel-Crafts alkylation in the presence of aluminum chloride AlCl3. Emergency emission is unintentional release of pollutants into the environment (atmosphere, water, soil) as a result of an accident on technical systems. Emergency environment is an accident in which pollutants enter the environment in an amount that poses a threat to the environment, people and property. Emergency rescue works are actions to save people, material and cultural values, protect the natural environment in the emergency zone, localize emergencies and suppress or minimize the impact of specific hazards. They require special training, equipment and devices. Emissions are gas-dust substances to be discharged (released into the atmosphere) beyond production limits, including hazardous and / or valuable components that are trapped by the process gases and are disposed of in accordance with the requirements of national legislation and / or regulations. EMS-1 is a station, consisting of a KAMAZ automobile (a variant was developed on the basis of the Ural motor vehicle), in the back of which a multi-purpose universal modular laboratory is installed, equipped with instruments and equipment for sampling and analysis of water, soil air, meteorological parameters. The EMS-1 instrument complex consists of separate functional blocks, which can be combined into the following groups: – a set of instruments and equipment for sampling and analysis of air, water, soil samples; – a meteorological station (measurement of temperature, air humidity, atmospheric pressure, wind speed and direction); – a radiation monitoring unit. The instrumentation of the station allows to measure and monitor the following parameters: hydrogen sulfide, ammonia, nitrogen dioxide, carbon monoxide, sulfur dioxide in the air; hydrocarbon gas content in air samples; phenol in water samples; oil products in water and soil samples; phosphates, chlorides, sulfides in water samples; ionic composition and pH of water; heavy metals in water and soil samples; meteorological parameters; gamma radiation intensity. Environmental disaster is an extraordinary event caused by a change in the state of land, atmosphere, hydrosphere and biosphere under the influence of anthropogenic factors, and consists in the manifestation of a sharp negative impact of these changes on human health, their spiritual sphere, habitat, economy or gene pool.

Glossary Environmental disease (ecogenic) is a disease that belongs to a group of diseases associated with unfavorable ecological conditions of the vital activity of the population – first of all, high content of heavy metals, chemical toxicants, increased radiation. Environmental expertise of chemical technologies is an estimate of the lowwaste production in comparison with the developed standards or the best available samples. At the same time, the degree of economic and ecological danger of the method of production and technological redistribution into the environment, etc. is determined. Environmental impact is any negative or positive change in the environment, wholly or partly resulting from the activities of the organization, its products or services. Environmental monitoring is a system for monitoring the environment from anthropogenic pollution associated with human activities. Since natural ecological systems closely interact with each other, this predetermines the complexity and necessity of taking into account various natural and chemical factors when controlling the quality of the environment. To assess the degree of negative impact of pollution, environmental monitoring is carried out as a system for observing and monitoring changes in the composition and functions of various ecological systems. Environmental monitoring can be carried out on a global, national, regional or local scale. Environmental Monitoring Station (EMS) is a station (post) of environmental monitoring of air, an independent block design (block-box), designed to monitor atmospheric air, working area air and at the border of the sanitary protection zone. Environmental protection is a set of measures aimed at ensuring safety of human settlements, rational use of land and water, prevention of pollution of surface and groundwater, air basin, preservation of forest areas, nature reserves, protected zones, etc. EPA (The United States Environmental Protection Agency) is an agency of the US federal government established to protect the environment and human health, for which it develops and monitors compliance with the regulations based on laws, adopted by the Congress. The agency was proposed by Richard Nixon and began operating on December 2, 1970. The Agency is managed by an administrator appointed by the president and approved by the Congress. Since February 2017, this position has been occupied by Scott Pruitt. The administrator of the agency is a member of the US Cabinet. The EPA is headquartered in Washington, with regional offices in each of the 10 regions and 27 laboratories. The Agency conducts the environmental assessment, does research and engages in educational work. Its job is to monitor the implementation of the adopted standards and norms, some of these responsibilities are delegated to the states. The agency has about 15,000 full-time employees, and also works with many people on a contract basis. In March 2017, the Trump administration proposed to reduce by one-quarter the budget of the Environmental Protection Agency. By 2018, environmental spending will be reduced by 25% – to $ 6.1 billion. Each fifth employee will fall under the reduction. At the same time, Trump guarantees that the project will not endanger the safety of air and water. The cost of the program in 2018 will be $ 29 million. Priority will be the sewage treatment programs, including industrial wastewater, and the modernization of the water supply system. Ethane is a naturally gaseous straight-chain hydrocarbon (C2H6) extracted from natural gas and refinery gas streams.

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Actual ecological aspects of petrochemical manufactures Ethyl alcohol (ethanol or grain alcohol) is an inflammable organic compound (C2H5OH) formed during fermentation of sugars; used as an intoxicant and as a fuel. Exhaust gases (off-gases) are the spent substances in the engine, products of oxidation and incomplete combustion of hydrocarbon fuel. Emissions of exhaust gases are the main reason for exceeding the permissible concentrations of toxic substances and carcinogens in the atmosphere of large cities, the formation of smogs, which are a frequent cause of poisoning in confined spaces. Exhaust gas recirculation of the vehicle’s engine is restart-up of the fulfilled gases in the system of the car’s engine intake. Expanding clays are clays that expand or swell in contact with water, e.g., montmorillonite. Explosive limits are the limits of percentage composition of mixtures of gases and air within which an explosion takes place when the mixture is ignited. External surface is an external surface of particles of catalysts and adsorbents without their internal porous structure (an internal surface). Usually, superficial pores and cavities are also referred to the external surface if their width exceeds the depth. Extinction is disappearance of any systematic category of living species (from subspecies and higher) as a result of natural processes or human impact. In the epoch of extinction of dinosaurs, one species disappeared in 1000 years, from 1600 to 1950 – one species disappeared in 10 years, and now – 1 species per year. Extrudate is a product obtained by extrusion. Extrusion is a formation method in which a paste is extruded through a spinneret. The size of the holes in the spinneret determines the size and shape of the resulting particles. The quality of the product (extrudate) depends to a large degree on the water content and rheological properties in the initial paste, which are regulated by special additives. F Faujasite is a naturally occurring silica-alumina (SiO2-A12O3) mineral. Feedstock is petroleum as it is fed to the refinery; a refinery product that is used as the raw material for another process; the term is also generally applied to raw materials used in other industrial processes. Thus, it is a stock from which material is taken to be fed (charged) into a processing unit. The Fischer-Tropsch process is a catalytic process for production of liquid hydrocarbons from synthesis gas. Metal catalysts containing iron and cobalt are generally used. Due to exhaustion of world reserves of hydrocarbon raw materials this process was of particular importance for production of synthetic fuels and lubricant coal oils. The fixed catalyst is an immobilized catalyst in which the active site is attached to the carrier by a covalent chemical bond. Typically, this term refers to systems in which the surface functional group of a carrier is covalently bound to one of the ligands in the organometallic complex. Such a system retains the properties inherent in free metal complexes in solution, including, for example, the mechanism of catalytic conversion. The advantage of fixed catalysts compared with metal complexes in solution is the possibility to separate the catalyst from the reaction mixture by filtration.

Glossary Flame neutralizer of exhaust gases of the car engine is a device for neutralization of the exhaust gases of the engine by afterburning in an open flame. The flammability group is the term used in determining the category of production in case of fire and depending on the flash point. Flammable liquids (FL) are combustible liquids with a flash point in a closed crucible not above 61°C. FL are subdivided into especially dangerous – having a flash point below -18°C, constantly dangerous – with a flash point from-18 to 23°C and dangerous at elevated temperature – with a flash point from 23 to 61°C. The flash point is the lowest temperature of a combustible substance, at which vapor or gases are generated above its surface that can flare in the air from the ignition source, but the rate of their formation is still insufficient for sustainable combustion. The flowing and circulating reactor is the reactor used in laboratory research in which the catalyst is in a circulating contour with rapid circulation of reactionary mixture through the catalyst. Reagents are injected with a constant speed into the contour, and products with a constant speed are taken away from a contour. Due to rapid circulation of the mixture in the contour a number of advantages is reached (constant temperature is established, influence of external diffusion, etc. is eliminated). The flowing reactor is the reactor of continuous action having a constant stream of reagents at the entrance to the reactor and a constant stream of products at the exit from the reactor. The fluidized bed reactor is a reactor in which solid catalyst particles (0.01-0.1 mm in size) are suspended in an upward flow of gaseous reactants. The advantages of this type of reactor are the intensive heat exchange between the catalyst particles, the absence of external diffusion inhibition, and the ease of catalyst loading. The lack of a fluidized bed is an increased abrasion of the catalyst particles. Reactors of this type are suitable for reactions with very high heat release, or in cases where the catalyst needs frequent replacement. The fluidized bed reactor is a fluidized bed reactor containing a gas, liquid, and a solid phase. Forming is a stage of preparation of catalysts which is responsible for the external sizes and a form of particles of the ready catalyst. Forming can be carried out by various methods (spray drying, extrusion, tabletting, granulation, etc.). Fraction is one of the portions of fractional distillation having a restricted boiling range. It is the share of petroleum which is boiling away in a particular interval of temperatures. Fraction С2+ is a mixture of hydrocarbons with the number of carbon atoms from 2 and above. Most often, this term means light hydrocarbons with the carbon number of up to 5. Fractional composition is an important indicator of quality of petroleum. It is defined in the laboratory distillation in the course of which at gradually increasing temperature the parts – the fractions differing from each other by the range of boiling – are distillated from petroleum. Fractional composition of petroleum shows the content of various fractions in it which are boiling away in particular temperature intervals and the content of substances in them. Fractionating column is a process unit that separates various fractions of petroleum by simple distillation, with the column tapped at various levels to separate and remove fractions according to their boiling ranges.

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Actual ecological aspects of petrochemical manufactures Free sulfur is sulfur that exists in the elemental state associated with petroleum; sulfur that is not bound organically within the petroleum constituents. A free-dispersing system is a dispersed system in which the particles of a dispersed phase freely participate in Brownian motion, for example, sol. Fuel Gas is a refinery gas used for heating. Fuel oil is also called heating oil, it is a distillate product that covers a wide range of properties. Functional group is the part of a molecule that is characteristic of a family of compounds and determines the properties of these compounds. G Gallon is a unit of measurement of volume, equal to ≈ 3,785 l. Gas is a natural mixture of hydrocarbon, non-hydrocarbon compounds and elements that are in formation conditions in the gaseous phase, or dissolved in oil or water conditions, and under standard conditions – only in the gaseous phase. Gas analyzers are devices for determining the qualitative and quantitative composition of gas mixtures contained in the atmosphere. Gas analyzers make it possible to obtain continuous air pollution characteristics and to identify maximum concentrations of impurities that may not be recorded during periodic sampling of air several times a day. The gas cap is the accumulation of free oil gas in the most elevated part of the oil reservoir above the oil deposit. Gas cleaning is a set of measures and (or) technologies aimed at capturing solid, liquid or gaseous substances contained in the gas emissions of industrial enterprises in the atmosphere. The gas field – the term means one or several gas deposits, confined territorially to one area, or associated with a favorable tectonic structure (anticlinal fold, dome, etc.) or other type of trap. Gas factor is the amount of natural gas (in cubic meters) per 1t or 1m3 of oil. Gas flow is the amount of gas in volume or weight terms, released from a well or from any source per unit of time (per hour, per day, etc.). Gas-condensate deposit is a deposit in which hydrocarbons in the conditions of the existing reservoir pressure and temperature are in the gaseous state. At a decrease in pressure and temperatures the phenomenon of the so-called “return condensation” occurs, when hydrocarbons partially pass into a liquid phase and remain in pore channels of the layer from which it is difficult to extract them. The operation of the gas condensate deposit in order to avoid these losses must be done with maintaining the pressure above the reverse condensation point, for which the injection of extracted gas back into the formation after its topping is organized. Gas condensate factor is the amount of gas (m3) from which 1 m3 of condensate is extracted. The value of gas condensate factor can be for the various fields from 1, 500 до 25, 000 m3/m3. Gas hydrates are solid compounds (clathrates) in which the gas molecules under certain temperature and pressure fill the structure cavities of the crystal lattice formed by water molecules by means of hydrogen bonding. The water molecules are

Glossary moved apart by gas molecules – the density of water in hydrated state is increased to 1.26-1.32 cm3/g (ice density – 1.09 cm3/g). Externally, the hydrates look like snow. They are typically formed at temperatures below 30°C, at pressures greater than 0.5 MPa. Disintegration of gas hydrates is possible when the temperature rises with decreasing pressure, and by introducing the substances, which decompose hydrate, such as calcium bromide, into the reservoir. Gas mode (dissolved gas mode) is the mode of operation of the oil deposit in which oil is entrained to the bottom of the wells by more mobile masses of the expanding gas, which transforms from the dissolved to the free state, when the pressure in the reservoir decreases below the saturation point. Gas oil is middle-distillate petroleum fraction with a boiling range of about 175 – 400 ºC, usually includes diesel fuel, kerosene, heating oil, and light fuel oil. It is a petroleum distillate with a viscosity and boiling range between those of kerosine and lubricating oil. Gas-oil ratio is a ratio of the number of cubic feet of gas measured at atmospheric (standard) conditions to barrels of produced oil measured at stocktank conditions. Gaseous pollutants are gases released into the atmosphere that act as primary or secondary pollutants. Gasoline is a blend of naphthas and other refinery products with sufficiently high octane and other desirable characteristics to be suitable for use as fuel in internal combustion engines. It is fuel for the internal combustion engine that is commonly, but improperly, referred to simply as gas. The gas-oil reservoir is a reservoir in which free gas occupies the entire higher part of the structure and is directly in contact with oil occupying a reduced part of the structure in the form of a rim, and the volume of the oil part of the deposit is much smaller than the volume of the gas cap. At a large depth of bedding, the gas cap, regardless of its size, may contain petroleum hydrocarbons in the gas-condensate state. Gasoline type jet fuel (naphtha type jet fuel) includes all light hydrocarbon oils for use in aviation turbine power units, distilling between 100 °C and 250 °C. It is obtained by blending kerosenes and gasoline or naphthas by the method at which the aromatic content does not exceed 25% in volume, and the vapour pressure is between 13.7 kPa and 20.6 kPa. Gas processing plant (GPP) is an enterprise where drying, desulfurization (removal of sulfur compounds) and separation of associated oil or natural gas into components – methane and other hydrocarbons takes place. The gas saturation pressure is a pressure at which a certain volume of gas is in a dissolved state in the oil. Geoecology is a scientific direction that studies the Earth as a system of geospheres in the process of their interaction with the whole aggregate of living matter. Global warming is an increase in the average temperature of the atmosphere in the scale of the planet, caused by a combination of natural and / or technogenic factors. Granules are the substances in the form of unbound particles with a size of more than 1 mm. Granulation is a method for forming granules from powders. Usually, this procedure is performed when the powder is moistened in a rotating drum.

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Actual ecological aspects of petrochemical manufactures Global ecology is a complex scientific discipline that studies the biosphere as a whole. The fundamentals of global ecology are formulated by M.I. Budyko, who considers it a central problem of the cycle of substances in the biosphere. H Harmful substances are substances which at contact with a human body, in case of violation of safety requirements, can cause the production injuries, professional diseases or deviations in the state of health found by the modern methods both in the course of work, and in the remote terms of life of this and subsequent generations. They are chemical or biological substances or a mixture of such substances that are contained in the ambient air and which in certain concentrations have harmful effects on human health and the environment. Heterogeneous catalysis is a phenomenon of the change in the rates of chemical reactions under the influence of catalysts, which form a separate phase, while the reagents are in a different phase. The reactants are contacted with the catalyst at the interface. The most widespread systems are those in which reactants from a liquid or gaseous phase interact with a solid catalyst. The heterogeneous catalyst is a catalyst existing in the reaction mixture as a separate phase. A catalytic reaction involving a heterogeneous catalyst necessarily takes place at the phase boundary. Unlike a homogeneous catalyst, the advantage of a heterogeneous catalyst is the ease of separating the reaction products from the catalyst. High-boiling distillates are fractions of petroleum that cannot be distilled at atmospheric pressure without decomposition, e.g., gas oils. High-sulfur petroleum is a general term for petroleum having more than 1 wt % sulfur; this is a very rough definition and should not be construed as having a high degree of accuracy because it does not take into consideration the molecular locale of sulfur. With other equal parameters, there is little difference between petroleum having 0.99 wt% sulfur and petroleum having 1.01 wt% sulfur. Hydrocarbon compounds are chemical compounds containing only carbon and hydrogen. Hydrocarbon gasification process is a continuous, noncatalytic process in which hydrocarbons are gasified to produce hydrogen by air or oxygen. Hydrocarbon resources are resources such as petroleum and natural gas that can produce naturally occurring hydrocarbons without application of conversion processes. Hydrocarbon-producing resource is a resource such as coal and oil shale (kerogen), which produce derived hydrocarbons by application of conversion processes; hydrocarbons produced by this method are not naturally-occurring materials. Hydrocracking is a catalytic process, the cracking of heavy hydrocarbons in the presence of hydrogen H2. In addition to cracking reactions, hydrogenolysis, hydrogenation of aromatic hydrocarbons, the opening of cycles in naphthenes, hydrodealkylation of alkylaromatic compounds and naphthenes occur. Hydrocracking catalysts can be oxides and sulphides of Ni, Co and Mo. Hydrodenitrogenation is the removal of nitrogen by hydrotreating.

Glossary Hydrodemetallization is the removal of metallic constituents by hydrotreating. Hydrogeneration is the chemical addition of hydrogen to a material in the presence of a catalyst. Hydrodesulfurization is a catalytic process of the removal of sulfur from oil or its fractions by hydrogenation of sulfur-containing compounds to form hydrogen sulfide and convert to hydrocarbons and H2S. The process is carried out in the presence of hydrogen H2. The catalysts are supported oxides of Co and Mo, which under the process conditions become sulfides. Hydrogenolysis is a catalytic process of rupture of C-C or C-X bonds (X = N, S, O, etc.) in hydrocarbons under the action of hydrogen H2. It is carried out on catalysts of hydrogenation and dehydrogenation (for example, metal catalysts). Often, the hydrogenolysis reaction requires high temperatures and a strong binding of the reactants to the catalyst and is therefore difficult to implement. Hydrothermal synthesis is a method of obtaining carriers and catalysts in aqueous solutions at temperatures above 100°C and pressures above 1 atm. Under such conditions, water can dissolve many substances (oxides, silicates, sulfides), which under normal conditions are practically insoluble. Advantages of the method are the ability to synthesize large crystals of high quality, as well as the possibility of obtaining crystals of substances that are unstable near the melting point. The main parameters of hydrothermal synthesis are the initial pH of the medium, the duration and temperature of the synthesis, the pressure in the system. Hydrotreating is the removal of heteroatomic (nitrogen, oxygen, and sulfur) species by treatment of a feedstock or product at relatively low temperatures in the presence of hydrogen. I The ignition temperature is a temperature of combustible substance at which it emits combustible vapors and gases with such a speed, that after their inflaming from a source of ignition, a steady combustion is observed. The Ili-Ridil mechanism is a mechanism of a heterogeneous catalytic reaction, in which the compound adsorbed on the surface of a solid catalyst reacts with a molecule from the gas or liquid phase. Impact anthropogenic is the sum of direct and indirect effects of human activities on the environment, including human health and safety, flora, fauna, soil, air, water, climate, landscape and historical monuments or other physical structures or interaction among these factors. Impact on climate is changes in the global energy of the Earth as a result of accumulation of carbon dioxide and other “greenhouse gases”, changes in the density of the ozone screen, direct release of energy, etc. It is assumed that, while maintaining current trends in the climate, the average world air temperature by the middle of the 21st century can rise by 2-4.5°C. Impurities are substances that are present in small (trace) amounts in the feed, or in the catalyst. Usually this term implies that within the developed chemical technology it is difficult to control the composition of these substances and their quantity.

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Actual ecological aspects of petrochemical manufactures The inhibitor is a substance that slows down the chemical reaction. This term is applied to any reactions (catalytic, non-catalytic, chain). Sometimes for such substances the term negative catalyst is used, which is not recommended by IUPAC rules. The effect of inhibitors can be due to a variety of mechanisms. For example, some inhibitors are irreversibly consumed during the reaction. In case of enzymatic reactions chemical linkng of inhibitor with enzyme is the frequent reason for a delay of the reaction. Industrial cleaning (or purification) is the purification of gases for the purpose of subsequent utilization or return to production of a separated gas or a product transformed into a harmless state. This type of purification is a necessary stage of the technological process with this technological equipment connected to each other by material flows in accordance with the strapping of the apparatus. Industrial ecology is the scientific basis of rational nature management. It is the independent science studying the influence of the industrial activity on the biosphere and its evolution in the technosphere and defining the ways of transition of the technosphere, rather painless for the human civilization, to a noosphere. The methodical basis of the course of industrial ecology is a scientific analysis of the ecological characteristics of production (technological process, hardware, raw and auxiliary materials, their possible impact on the environment). On the basis of the detailed analysis, the real impact of production (production complexes) on the biosphere is evaluated, a forecast of the state of the environment is given, and measures to minimize the impact of economic entities on nature are planned. The main areas of industrial ecology are: – greening of technologies; – creation of low-waste processes; – cleaning the atmosphere and water resources from harmful impurities; – processing of solid waste (or their burial); – use of economic and legal levers for environmental protection. Industrial ecology purposes are solution of problems of rational use of natural resources, prevention (at the first stage – restriction) of environmental pollution, combination of technogenic and biogeochemical circulations of substances. In other words, industrial ecology is a means for the sustainable functioning of ecological and economic systems. Index group is a part of atoms of the reacting molecule which directly interacts with the surface of the catalyst at adsorption. The induction period is the initial stage of the chemical transformation, during which an increase in the reaction rate is observed (self-acceleration of the reaction). The induction period can be observed in catalytic processes due to various factors (for example, autocatalysis, heating of the system in the case of highly exothermic reactions, adsorption of interfering impurities from the reaction mixture onto the catalyst, etc.). The integrated mode of the reactor is an ideal operating mode of the reactor at which a considerable conversion of initial reagents at the outlet from the reactor is reached. The interface of the phases is the boundary separating the two neighboring phases. Sometimes this term refers to a surface layer thickness of a few atoms, which are different in energy from atoms in the bulk of each phase. For solid particles, this

Glossary is an external monolayer consisting of a regular matrix of surface atoms (or ions), as well as internal and external surface defects of various types. Internal surface is a part of an interface of phases which belongs to pores in particles of the catalyst or adsorbent. The other part of the surface belongs to an external (geometrical) surface of particles. At high porosity the internal surface can considerably (up to 106 times) surpass the external surface in the area. Isomerization is a catalytic process for obtaining high-octane components of commercial gasoline from low-octane oil fractions. As a result of the process, linear hydrocarbons are isomerized into branched hydrocarbons. Heterogeneous acid catalysts of various types are used: aluminoplatinum fluorinated catalysts (high-temperature isomerization, 360-440°C), zeolite catalysts (medium-temperature isomerization, 250-300°C); alumina promoted by chlorine, or sulfated zirconium oxide (low-temperature isomerization, 120-180°C). Isomerism is the phenomenon of the existence of compounds that have the same composition (the same molecular formula), but a different structure. K Kerosene (kerosine) is a fraction of petroleum that was initially sought as an illuminant in lamps; a precursor to diesel fuel. Kerosene type jet fuel is a distillate used for aviation turbine power units. It has the same distillation characteristics between 150°C and 300°C (generally not above 250°C) and flash point as kerosene. The kinetic mode is implementation of catalytic reaction in conditions when the kinetics of process isn’t complicated by diffusion processes (for example, the intra kinetic mode for the heterogeneous catalyst). L Laminar flow is the flow of a liquid or gas, in which particles of matter move in the direction of flow in an orderly and constant linear velocity. An increase in the flow rate or a decrease in the viscosity of the medium can lead to transition of a laminar flow into a turbulent flow. The Langmuir-Hinshelwood mechanism is the mechanism of a heterogeneous catalytic reaction, in which the slowest stage is the reaction between chemisorbed particles. In this case, the adsorption (chemisorption) of the reagents and the desorption of the products are considered as fast equilibrium processes. Leaching is the transition into a solution of one or more components of a solid substance when it interacts with a solvent. Selectivity of leaching of a particular component is determined by the solubility of the compounds, chemical properties of the solvent, and the structure of the solid. Leaded gasoline is gasoline containing tetraethyl lead or other organometallic lead antiknock compounds. Lean gas is the residual gas from the absorber after the condensable gasoline has been removed from the wet gas.

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Actual ecological aspects of petrochemical manufactures Lean oil is the absorption oil fed to absorption towers in which gas is to be stripped. After absorbing the heavy ends from the gas, it becomes fat oil. When the heavy ends are subsequently stripped, the solvent again becomes lean oil. The level of pollution of the environment by the waste production is estimated by multiplicity of excess of maximum permissible (allowable) concentration (MPC or MAC) of substances entering natural objects. The biggest part of hydrocarbon pollution, 75%, goes to the atmosphere, 20% to the surface and ground waters, and 5% – to the soil. The lifetime, τ, is the lifetime of the molecule, which is destroyed by the firstorder kinetics, the time of the molecule concentration decrease by 1/e from its initial value. The lifetime is equal to the reciprocal of the rate constants of the first-order reactions leading to the death of the molecule. The time of life of particles in the notfirst order reactions depends on the initial concentration of the substance. In this case it is called the “observed time of life” or the “death time”. In some cases the term “half-decay time” is used, which is the time of half reduction in the concentration of the substance from the initial one. Light hydrocarbons are hydrocarbons with molecular weights less than that of heptane (C7H16). Light oil is the products distilled or processed from crude oil up to, but not including, the first lubricating-oil distillate. Light petroleum is petroleum having the API gravity greater than 20º. Ligroine (Ligroin) is a saturated petroleum naphtha boiling in the range of 20 to 135 °C (68 to 275 °F) and suitable for general use as a solvent; also called benzine or petroleum ether. The limiting stage is the elementary stage in the complex process (consisting of several consecutive stages) which is characterized by the difference of chemical potentials, maximum for process, between the interacting reactionary groups. For simple and quite often for complex chemical processes the limiting stage can coincide with the speed – defining (speed – controlling) stage. Liquefied Hydrocarbon Gases (LHG) are the compressed hydrocarbon gases or their mixtures with boiling temperatures from -50 to 0 °C. The major LHGs are propane, butane, isobutane, butylene of various structures and their mixtures of different structures. They are generally made from associated petroleum gas, and also at oil refineries. Liquefied natural gas (LNG) is a natural gas cooled to about -160 °C under atmospheric pressure and condensed to its liquid form named LNG. LNG is odourless, colourless, non-corrosive and non-toxic. Liquefied petroleum gases (LPGs) are light paraffinic hydrocarbons derived from the refinery processes, crude oil stabilisation and natural gas processing units. They mainly consist of propane (C3H8) and butane (C4Hl0) or a combination of the two. They could also include propylene, butylene, isobutene and isobutylene. LPGs are normally liquefied under pressure for transportation and storage. The liquid neutralizer of exhaust gases of the car engine is a device for neutralization of the exhaust gases of the car engine by chemical binding by liquid reagents. Liquid Off Take System (LOT system) is an advanced concept in multi-cylinder installations. This system is widely used in commercial and industrial applications

Glossary only where high pressure is required, and not for domestic purposes. The LOT system picks up liquid LPGs using the LOT valves and turns into steam using an evaporator. LOT systems are compact, safe and economical, since the liquid is completely drawn out of the cylinder and has no residual losses. About a half of losses of oil when transporting is formed when loading of ballast and cleaning of tankers. Though 80% of the world tanker fleet uses the system of control actions of Liquid off Take System (LOT) for reduction of the amount of oil products getting to the sea during ballast release, more than 70% of pollution of the sea is the share of 20% of the tankers, which do not use the LOT system. The LOT system differs in the fact that as ballast in it water and oil products are used. Less dense oil products settle down in the top part of tanks, and rather clear sea water merges from the lower part in the sea. The oil products mixed with a small amount of sea water remain in tanks and then are overloaded to the next tanker at its filling except for some special cases when oil doesn’t contain admixture of sea water. Advantages of LOT systems: – less space is required than volumetric installations; – there are no residual losses; – constant pressure. Lubricants are hydrocarbons produced from distillate by-products; they are mainly used to reduce friction between bearing surfaces. They include all finished grades of lubricating oil, from spindle oil to cylinder oil, and those used in greases, including motor oils and all grades of lubricating oil base stocks. M Macrokinetics is the study of kinetic regularities of chemical reactions, under conditions when they are accompanied by heat transfer and mass transfer phenomena. Macropores are the pores with an effective size of more than 50 nm. A massive catalyst is a heterogeneous catalyst, consisting entirely of an active component, for example, Raney nickel. Mass transfer is the diffusion or convection of a substance caused by different concentrations or electric potentials in the considered initial and final states. The maximum allowable (permissible) concentrations (MAC or MPC) are concentrations of substances that, with daily (except weekend) work for 8 hours or with a different working day, but not more than 41 hours a week, cannot cause diseases or abnormalities in the state of health during the whole working period. Harmfulness of the substance can be determined by MAC in the air of the working area. The mechanism of the chemical process is a set of all intermediates and transition states of the chemical process, which explains transformation of the initial reagents into final products. Mercaptans are organic compounds having the general formula R-SH. Mercury porometry is a method of porometry based on the property of liquid mercury not to moisten (wet) the majority of solid bodies. The volume of mercury entering the pores is measured, depending on the applied pressure. The method can be used to determine the pore size in a wide range (from 3 nm to 400 μm). Mesopores are pores with an effective size of 2 nm to 50 nm.

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Actual ecological aspects of petrochemical manufactures Methanation is a catalytic process of removing small amounts of carbon monoxide from a gas stream. It leads to the production of methane by the reaction CO + 3H2 → CH4 + H2O. Nickel supported on alumina is used as the catalyst. The process can be carried out at any pressure, typical process temperatures are 200-370°C. Methyl alcohol (methanol; wood alcohol) is a colorless, volatile, inflammable, and poisonous alcohol (CH3OH) traditionally formed by destructive distillation of wood or, more recently, as a result of synthetic distillation in chemical plants. Micropores are pores with effective size less than 2 nm. Microspherical catalyst is a catalyst in the form of microspheres with a diameter from 20 to 200 microns used in a fluidized bed reactor. The moisture capacity of the carrier is the amount of solvent that is absorbed when the porous system is filled in a pre-dried carrier. Mineral oil is the older term for petroleum; the term was introduced in the nineteenth century as a means of differentiating petroleum (rock oil) from whale oil which, at the time, was the predominant illuminant. Mineral seal oil is a distillate fraction boiling between kerosine and gas oil. Mineral wax – from yellow to dark brown, solid substances that occur naturally and are composed largely of paraffins; usually found associated with bulk mineral matter, as a filling in veins and fissures or as an interstitial material in porous rocks. Mineralization is a process of complete conversion of organic matter into carbon dioxide, water and other simple inorganic substances, depending on the heteroatom in the starting material. A mixed catalyst is a catalyst consisting of two or more components, each of which is catalytically active with respect to the reaction. Usually, in mixed catalysts, the components are in commensurate amounts. An increase in the activity of such catalysts can be achieved through the interaction of the components with the formation of a new more active phase. Example: iron-molybdenum catalyst for the oxidation of methanol to formaldehyde has the highest activity at a ratio of iron and molybdenum oxides of 1.5: 1 (the phase of iron molybdate is formed). Modifier – this term is used in asymmetric catalysis and means a chiral substance, without which the catalyst cannot produce an optically active product. For example, the Raney nickel catalyst is capable of performing asymmetric hydrogenation reactions if an optically active isomer of tartaric acid is present on its surface. Monitoring is a system of long-term observation, assessment, monitoring and forecasting of the state and change of the objects. A monomer is a component of a polymer, its structural unit, a molecule capable of polymerization or polycondensation. It usually contains one (olefins) or two (dienes) double bonds involved in the polymerization. Morphology is geometrical features of the structure of solid substances, including a geometrical form and the degree of crystallinity of particles of the substance, and also a geometrical form of the agglomerates formed of primary particles and the presence of porous structure in them. Motor gasoline consists of a mixture of light hydrocarbons distilling between 35 °C and 215 °C. It is used as a fuel for land-based spark ignition engines. Motor gasoline may include additives, oxygenates and octane enhancers. Motor gasoline can be divided into two groups:

Glossary – unleaded motor gasoline: motor gasoline where lead compounds have not been added to enhance octane rating. It may contain traces of organic lead. – motor gasoline with Pb added to enhance octane rating. It includes motor gasoline blending components (excluding additives/oxygenates), e.g. alkylates, isomerate, reformate, cracked gasoline destined for use as finished motor gasoline. Motor octane method is a test for determining the knock rating of fuels for use in spark-ignition engines. Multifunctional (polyfunctional) catalysis is a difficult complex multistage catalytic reaction with participation of the multifunctional (polyfunctional) catalyst. Multifunctional (polyfunctional) catalyst is a catalyst containing active centers with different functions. Such catalysts are effective in reactions with several intermediate stages, each of which requires catalytic centers of their own type. N Naphtha is a generic term used for low boiling hydrocarbon fractions that are a major component of gasoline. Aliphatic naphtha refers to naphthas containing less than 0.1% benzene with carbon numbers from C3 through C16. Aromatic naphthas have carbon numbers from C6 through C16 and contain significant quantities of aromatic hydrocarbons such as benzene (> 0.1%), toluene, and xylene. Naphtha is a feedstock destined for petrochemical industry (e.g. ethylene manufacture or aromatics production). Naphtha comprises material in the 30 °C and 210 °C distillation range or part of this range. This term is also applied to refined, partly refined, or unrefined petroleum products and liquid products of natural gas, the majority of which distills below 240°C (464°F). Naphthenes are hydrocarbons (cycloalkanes, cycloparaffins) with the general formula CnH2n, in which the carbon atoms are arranged to form a ring. Natural gas comprises gases, occurring in underground deposits, whether liquefied or gaseous, consisting mainly of methane. It includes both “nonassociated” gas originating from fields producing hydrocarbons only in gaseous form, and “associated” gas produced in association with crude oil as well as methane recovered from coal mines (colliery gas). Natural gas liquids (NGLs) are hydrocarbon liquids condensed during processing of hydrocarbon gases produced from oil or gas reservoir; see also natural gasoline. Natural gasoline is a mixture of liquid hydrocarbons extracted from natural gas suitable for blending with refinery gasoline. Natural hydrocarbon gases are a mixture of saturated hydrocarbon type СnН2n+2. The main component is methane, CH4. Natural gasoline plant is a plant for extraction of fluid hydrocarbon, such as gasoline and liquefied petroleum gas, from natural gas. Neutralization is a decrease of toxicity of exhaust gases with the help of devices installed in the engine’s exhaust system. Negative catalyst – see inhibitor. The noosphere is a new geological envelope of the Earth created by human society on a scientific basis (according to ideas and conclusions of V.I. Vernadsky).

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Actual ecological aspects of petrochemical manufactures Normal hydrocarbons are hydrocarbons of unbranched, linear structure of the chain. NOx storage and reduction system (NSR) is a practical method for removing NOx in excess oxygen conditions. O Octane number is a measure of the detonation resistance of fuel, that is, the ability of the fuel to withstand self-ignition when compressed in the combustion chamber of a gasoline engine. It is the number indicating relative antiknock characteristics of gasoline. The name comes from the fact that in the conventional scale of detonation resistance the number 100 is assigned to a normal octane. Oil (petroleum) is an oily liquid, usually brown to almost black, less often brownish-red to light orange, with a specific odor. It is a mixture of hydrocarbons of methane, naphthenic and aromatic series with an admixture of (usually minor) sulfur, nitrogen and oxygen compounds. The specific gravity is seldom below 0.7 and above 1, fluctuating usually in the range 0.82-0.89. The low specific gravity of oils (light oils) can be due to their chemical character – the predominant content of methane hydrocarbons and the fractional composition – high content of gasoline. Heavy oils have a high specific gravity due to the high content of asphalt-resinous substances, the predominance of cyclic structures in the structure of hydrocarbons and a low content of easily boiling fractions (the initial boiling point sometimes exceeds 200 °C). The sulfur content of the oils is usually lower than 1%, but sometimes reaches 5 – 5.5%. The amount of paraffins varies from trace amounts to 10% or more. Oil with a high content of paraffin has increased freezing temperatures (from higher than 0 °C to + 20 °C), oil with a low content of paraffin sometimes stiffens at temperatures below – 20 °C. The maintenance of asphalt фnd resinous components and viscosity of heavy oil, as a rule, above, than that of light oil. Oil-bearing characteristics – 1) the direct separation of liquid oil, 2) the impregnation of rocks with oil; 3) deposits of solid bitumens (asphalt, ozocerite); 4) release of combustible gas; 5) the presence of mud volcanoes; 6) an oil or bituminous smell emitted by the rock, sometimes only after a strong heating of it; 7) coloring of the gasoline or benzene extract of the determined rock. Oil-bearing characteristics indicate the possible presence of oil in the rocks in the considered rocks of this area. Oil-bearing rocks are rocks impregnated with oil. Typically, oil impregnates well-porous rocks – sands, sandstones, fossilized limestones, etc., creating from such rocks the industrial-oil-bearing horizons to be developed. Oil-bearing rocks are also clays, etc., dense rocks, but the oil in them is dispersed and slightly concentrated only in bends and crushed parts. The oil-bearing region is a set of several adjacent genetically linked structures with signs of oil or a set of similar oil deposits with similar oil-bearing suites. Oil recovery is a degree of completeness of oil recovery. Oil reservoir is a layer of rock, more or less impregnated with oil. Oil saturation of layer is an amount of the oil which is available in layer in relation to the total volume of pores, cavities and cracks in oil-containing rock. In natural conditions, oil saturates a small part of the pores, and larger ones. Small pores,

Glossary due to the action of surface tension forces, are occupied by water. The smaller pores, the more “buried” water in the layer. In some layers, the amount of this water is quite significant – up to 40%. “Buried” water in the process of exploitation of the reservoir does not usually manifest itself, and the wells give waterless oil. Olefins is a family of unsaturated hydrocarbons with one carbon-carbon double bond and the general formula CnH2n. Open pores are channels or cavities that communicate with the outer surface of the particle. Molecules from the surrounding space can freely penetrate into the open pores by diffusion. Oxidation catalysts are catalysts that provide a quick solution to lowering emissions. Conversion of carbon monoxide, hydrocarbons and aldehydes into H2O and CO2 are the result of work of an oxidation catalyst. Products of incomplete combustion – HC and CO – are oxidized in the exhaust system by a catalyst that creates CO2 (carbon dioxide) and H2O (water). Oxygenate is an oxygen-containing compound that is blended into gasoline to improve its octane number and to decrease gaseous emissions. Ozone “hole” is a significant space in the ozonosphere of the planet with a markedly (up to 50%) reduced ozone content. In 1985 – 1988 years ozone “holes” were recorded over Antarctica, Australia and the Arctic. It is supposed that they have an anthropogenic origin, for example, freons (chlorofluorocarbons), oxides of sulfur and nitrogen are recognized as ozone destroyers. P Paraffins is a family of saturated aliphatic hydrocarbons (alkanes) with the general formula CnH2n+2. Paraffin waxes are saturated aliphatic hydrocarbons. These waxes are residues extracted when dewaxing lubricant oils. They have a crystalline structure which is more or less fine according to the grade. Their main characteristics are: colourless, odourless and translucent, with a melting point above 45°C. Particle size distribution is the statistical distribution of the number of particles, depending on their size. It is determined by microscopic methods. Passivation is a method of protecting metal catalysts by means of a small controlled oxidation of the surface in an oxygen medium. The resulting oxide layer on the surface of metal particles prevents further oxidation of the metal. Particulate matter (PM), also known as particle pollution, is a complex mixture of extremely small particles and liquid droplets that get into the air. Once inhaled, these particles can affect the heart and lungs and cause serious health effects. Petroleum (crude oil) is a naturally occurring mixture of gaseous, liquid, and solid hydrocarbon compounds usually found trapped deep underground beneath impermeable cap rock and above a lower dome of sedimentary rock such as shale; most petroleum reservoirs occur in sedimentary rocks of marine, deltaic, or estuarine origin. Petroleum coke is a black solid by-product, obtained mainly by cracking and carbonising petroleum-derived feedstock, vacuum bottoms, tar and pitches in processes such as delayed coking or fluid coking. It consists mainly of carbon (90% to 95%)

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Actual ecological aspects of petrochemical manufactures and has low ash content. It is used as a feedstock in coke ovens for the steel industry, for heating purposes, for electrode manufacture and for production of chemicals. Petroleum natural gases are gases consisting of a mixture of gaseous hydrocarbons of the paraffin series (СnН2n+2): methane CH4 (sometimes up to 99%), ethane C2H6, propane C3H8, butane C4H10, with an admixture of nitrogen, carbon dioxide, hydrogen sulfide and gasoline vapors. Distinguish dry gas (with a predominance of methane) and fatty gas (with a high content of heavy hydrocarbons). Pitch is the nonvolatile, brown to black, semi-solid to solid viscous product from the destructive distillation of many bituminous or other organic materials, especially coal; this term has been incorrectly applied to residua from petroleum processes where thermal decomposition may not have occurred. The plasticizer is a substance that is introduced into the material to give it plastic properties. Plastics are materials based on natural or synthetic polymers, which, under the influence of heating and pressure, can be molded into products of complex configuration and then stably retain the given shape. The production of synthetic plastics is based on polymerization, polycondensation or polyaddition reactions of low molecular weight raw materials derived from coal, oil or natural gas, such as benzene, ethylene, phenol, acetylene and other monomers. In this case, high-molecular bonds are formed with a large number of initial molecules. Plastics are inexpensive, lightweight and durable materials, which can readily be moulded into a variety of products that find use in a wide range of applications. As a consequence, the production of plastics has increased markedly over the last 60 years. Platforming is a reforming process using a platinum-containing catalyst on an alumina base. Point pollution is the ratio of the average concentration of pollution to the average MAC. Poisoning is a decrease in the activity of the catalyst, which is caused by the interaction of the active sites of the catalyst with the catalytic poison present in the reaction mixture. There are reversible poisoning and irreversible poisoning. In reversible poisoning, the catalytic activity is restored to its original level after removal of the poison from the reaction mixture. In case of irreversible poisoning, for example due to strong adsorption of the poison on the active centers of the catalyst, the catalytic activity remains low even after removal of the poison from the reaction mixture. In this case, the catalytic activity can be recovered by regenerating the catalyst, or by complete chemical processing of the poisoned catalyst. Pollution is introduction into the land water and air systems of a chemical or chemicals that are not indigenous to these systems or introduction into the land water and air systems of indigenous chemicals in greater-than natural amounts. Pollution (environment or surrounding medium) is the occurrence, introduction into the environment of usually not typical physical, chemical, or biological agents or their excess during the considered time of the natural background, often leading to negative consequences. Protection from pollution is ensured by a system of laws, rules and regulations, assessments of the impact of the projected facilities on the environment and environmental impact assessment. It is believed that the necessary protection against pollution is observed, if the maximum permissible concentration of harmful substances is not exceeded. Reducing pollution is an integral part of the

Glossary sustainable development society model. To overcome, evaluate and predict pollution, environmental monitoring is used, a system of environmental standards such as MPC (MAC) is developed. Pollution anthropogenic is pollution that has arisen as a result of people’s activities. Pollution of atmospheric air means entry into the air or formation in it of pollutants (particles of dust, smoke, acid droplets, exhaust combustion and automobile gases, etc.) in concentrations exceeding the hygienic and environmental quality standards for atmospheric air. The main polluters of air are industrial enterprises (the most toxic emissions are generated by the enterprises of non-ferrous and ferrous metallurgy, chemical, petrochemical industry), motor transport, heat and power engineering, agriculture. Pollution of atmospheric air leads to the destruction of the ozone layer, formation of smog, erosion of metal structures, cement stone and other building materials, causing degradation of ecosystems of soils and natural waters, increasing diseases of plants, animals, and people. Pollution of the catalyst is blocking of the active centers of the catalyst by the mechanical impurity which is contained in raw materials. In case of the heterogeneous catalyst mechanical impurity can also block porous system in granules of the catalyst and, thus, reduce the degree of use of the surface. Pollutions organized are pollutions caused by investigation, drilling, production, transportation, processes of primary (separation) and secondary (conversion) oil refining. Pollution prevention is a process of reduction or prevention of generation of pollutants. For example, pollution prevention may include changing a manufacturing process so that pollutants are no longer generated or greatly reduced. Alternatively, it may require installation of equipment that removes the pollutant before it is emitted or discharged to the environment so that it can be disposed of in a more appropriate manner. Pollution score is the ratio of the average annual concentration of this pollution to the average daily MAC. Pollutions unorganized are pollutions caused by leakage of oil and oil products due to leakage of equipment, emergency emissions, accidents during transportation, oil spills during fountains from wells, seepage of hydrocarbons through soil into reservoirs and other unforeseen circumstances that may also arise during drilling, production, pumping oil at pumping stations, operation of processing, oil-loading and pipeline transport equipment, etc. Pores are cavities (emptiness) or channels in solid particles. It is commonly believed that the depth of the pores exceeds their width. There are open pores and closed pores. Pore size distribution is a statistical distribution of pore volumes, depending on their size in the material under study. It is determined experimentally by the results of porosimetry or by calculation methods (by the adsorption isotherm). The pore size distribution affects the diffusion of the reactants and products in the solid-phase catalyst particles. The pore volume is the total volume of all pores present in the solid material. Porous structure of substance is the structure of porous space, i.e. a spatial arrangement and the sizes of pores in substance particles.

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Actual ecological aspects of petrochemical manufactures The predecessor is an initial or intermediate chemical compound which at the subsequent stages of synthesis passes into target substance. The pressure of the beginning of condensation is the pressure at which condensate in a layer is transformed from the gas into a liquid. Primary particles are particles of the smallest size, which can be identified as independent discrete constituents of the substance. Since the resolution of methods can depend strongly on a particular sample, usually when specifying the primary particles, it is also necessary to indicate the identification method (for example, transmission or scanning electron microscopy). The production rate of a well is the amount of production that is obtained from a well in a unit of time. Oil always has as its companion the oil gas released from the oil when it leaves the surface. Therefore, it is necessary to distinguish oil production and gas production. Some wells produce oil with water, sometimes in the form of an emulsion. For these wells, the water production rate and the emulsion discharge are distinguished in addition to the oil and gas production rate. In oil field practice, oil, emulsion and water flow rates are usually measured in tons per day, and gas production in cubic meters per day. Sometimes the water flow rate is expressed as a percentage of all the liquid produced by the well. Product yield is the relation of amount of the reagent which has turned into this product to the total of reagent given at a reactor entrance. The amount of reagent can be measured in various units (mol number, weight, etc.). A promoter is a substance added in small amounts to a catalyst in order to improve its activity, selectivity or stability. At the same time, the improvement in the properties of the catalyst is much greater than that which could be obtained as a result of the independent action of the promoter itself. Promoters can be a variety of substances. There are textural promoters (have a physical effect on the catalyst) and structural promoters (change the chemical properties of the catalyst). Propane-propylene fraction is a mixture of gaseous hydrocarbons with the number of carbon atoms 3, formed in the course of catalytic cracking during oil processing. Proved reserves are mineral reserves that have been positively identified as recoverable with current technology. The pulse reactor is a flow reactor operating in a pulsed mode. It is used in laboratory studies to study fast processes. In a pulsed reactor, a carrier gas stream is continuously fed through the catalyst, into which a stream of reagents is periodically added in the form of a short pulse. After each pulse, the reaction products can be analyzed, or the changes that have occurred to the catalyst are studied. The purity index is the ratio of the average daily MAC to the average annual concentration of this pollution. Pyrolysis is a thermal process of decomposition of hydrocarbon feedstock to produce ethylene, propylene, benzene, butadiene, hydrogen and a number of other products. Pyrolysis gasoline is a by-product from the manufacture of ethylene by steam cracking of hydrocarbon fractions such as naphtha or gas oil.

Glossary R Raffinate is the product resulting from a solvent extraction process and consisting mainly of those components that are least soluble in the solvents. The product recovered from an extraction process is relatively free of aromatics, naphthenes, and other constituents that adversely affect physical parameters. Rain acid means all types of precipitation (rain, hail, snow), in which the pH