Technogenic emissions into the atmosphere: impact on the environment and neutralization by catalytic methods: monograph 9786010434400

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AL-FARABI KAZAKH NATIONAL UNIVERSITY

L. R. Sassykova

TECHNOGENIC EMISSIONS INTO THE ATMOSPHERE: IMPACT ON THE ENVIRONMENT AND NEUTRALIZATION BY CATALYTIC METHODS Monograph

Almaty «Qazaq university» 2018

UDC 541.128, 547.261, 665.612.3, 662.767, 66.023:088.8, 66.093.673 LBC 20.1, 28. 080.1 я73, 35.514 S 23

Recommended for publication by the decision of the Academic Council of the al-Farabi KazNU (Protocol № 7 dated 26.02.2018) and RISO of the al-Farabi KazNU (Protocol № 5 dated 06.03.2018) Reviewers: Doctor of Chemistry, Professor B.S. Selenova Doctor of Chemistry, Professor S.M. Tazhibayeva

Sassykova L.R. S 23 Technogenic emissions into the atmosphere: impact on the environment and neutralization by catalytic methods: Monograph / L.R. Sassykova. – Almaty: Qazaq university, 2018. – P. 322. ISBN 978-601-04-3440-0 In the monograph issues of environmental impact of sources of technogenic emissions (the industry and motor transport) into the atmosphere are considered. Various methods of purification from technogenic emissions into the atmosphere are described. Catalytic cleaning methods are considered in detail. The material is based on the systematization of data published in modern domestic and foreign sources. In the monograph there are also materials of the multi-year researches of the author on catalytic purification of off-gases of the industry and motor transport. The monograph contains a detailed glossary and necessary illustrative material. The monograph is intended for researchers working in the field of ecology, catalysis, oil and gas business, chemical technology of organic and inorganic substances, oil refining, petrochemistry; bachelors, masters and doctoral students studying in the chemistry specialties. Publishing in authorial release

UDC 541.128, 547.261, 665.612.3, 662.767, 66.023:088.8, 66.093.673 LBC 20.1, 28. 080.1 я73, 35.514 ISBN 978-601-04-3440-0

© Sassykova L.R, 2018 © Al-Farabi KazNU, 2018

TERMS AND ACRONYMS ACEA ACS Abs Ads AF APG ASC AVT BFLH (or WFLH) CCh CDM CED-92

– European Automobile Manufacturers Association – Automated Control System – Absorption – Adsorption – Aftertreatment System – Associated Petroleum Gas – Catalyst for the Oxidation of Residual Ammonia – Atmospheric-Vacuum Tube – Broad (Wide) Fraction of Light Hydrocarbons

– Combustion Chamber – The Clean Development Mechanism – Conference on Environment and Development, held in 1992 in Rio de Janeiro CFR – Code of Federal Regulations CHT – Trap of CH °С – Degree Celsius DEF – Diesel Exhaust Fluid (Urea) Des – Desorption DOC – Diesel Oxidation Catalyst DPF – Diesel Particulate Filter DRT – Decomposition Reaction Tube DSG – Dry Stripped Gas EDP – Electrical Desalting Plant EG – Exhaust Gases EGR – Exhaust Gas Recirculation EFNPF – Elastic fine-pored polyurethane foams EHC – Electrically Heating Catalyst EPA – United States Environmental Protection Agency GHG – Greenhouse Gases GPP – A Gas Processing Plant GTL – Gas-to-Liquid Technology FCC – A Fluid Catalytic Cracking FL – Flammable Liquids HAPs – Hazardous Air Pollutants HC – hydrocarbons HC-SCR – Hydrocarbons-Selective Catalytic Reduction HPCM – High Porous Cellular Materials ICE – Internal Combustion Engines IPCC – The Intergovernmental Group of Experts on the UN Climate Change IR Spectroscopy – Infrared Spectroscopy K – Degree Kelvin KPO – Karachaganak Petroleum Operating LG – Liquefied Gases LMEHMC – Low Mass Electrically Heated Metal Catalytic

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LNT – Lean NOx trap LOC – Light Off Converter MAC (MPC) – The Maximum Allowable (Permissible) Concentrations of Substances in the Air of the Working Area MEA – Monoethanol Amine MHPCM – Metal High Porous Cellular Materials Mi – Miles MIC – Methylisocyanate MSC – Metal Supported Catalyst NCOC – North Caspian Operating Company NEDC – New European Driving Cycle – Selective Catalytic Reduction of NOx with Ammonia NH3-SCR NMOG – Non-Methane Organic Gases NSR – The NOx storage and reduction system ORC – Oxygen Retention Capacity PAH – Polycyclic Aromatic Hydrocarbons PCBs – Polychlorinated Biphenyls PJI – Projects of Joint Implementation PM – Particulate matter PVA – Polyvinyl Alcohol PVM – Paint and Varnish Material REE – Rare Earth Elements RSPM – Respirable Suspended Particulate Matter SAE – Society of Automotive Engineers SCR – Selective Catalytic Reduction SEM – Scanning Electron Microscopy SNG – Stable Natural Gasoline – Ambient Temperature Tamb TOF – Turnover Frequency TPD – Temperature-Programmed Desorption TPP – Thermal Power Plants TPR – Temperature-Programmed Reduction TPSR – Temperature-Programmed Surface Reaction TTB – Temporary Technological Bundle TWC – Three-Way Catalyst UCC – Union Carbide Corporation UCIL – Union Carbide India Limited UHCs – Unburned Hydrocarbons UNEP – United Nations Environment Program UNFCCC – United Nations Framework Convention on Climate Change VOCs – Volatile Organic Compounds WHO – World Health Organization WSSD-2002 – World Summit on Sustainable Development, held in 2002 in Johannesburg XAS – X-ray absorption spectroscopy λ – Coefficient of air excess, expressing the ratio between the actual and theoretically necessary amount of air

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I dedicate this book to the bright memory of my beloved father

INTRODUCTION  In recent decades, natural conditions on the surface of the Earth began to change markedly. Their causes are both natural fluctuations of various natural processes under the influence of heliocosmic and tectonic factors, and the growth of activity in human activity. Our reality is that the unity of man with Nature has become illusory, as the natural course of the evolution of the biosphere has disrupted. The man on our planet became the cause of the most significant changes in the biosphere. Anthropogenic impact began to be felt at the global level. 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 groundwaters, soil cover, changes in moisture exchange between the Earth’s surface and the atmosphere. Chemical substances created by man are accumulating in an increasing amount on the earth's surface, in the atmosphere and in the water environment, exerting a detrimental effect on the terrestrial biota. There is an increase in the rate of loss of biodiversity. Today, as never before, is very relevant F. Engels’s warning that «one should not be seduced by victories over nature, for nature avenges each person in revenge, that each of these victories has also very different, unforeseen consequences». Technical progress is the most important geoecological factor, the whole complex of processes for processing natural resources and the use of life support systems for the Earth. Humanity annually processes about 100 billion tons of raw materials, all the 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; produced products are thrown out to landfills in a relatively short time, causing environmental pollution.

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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. It is obvious that humanity needs to ensure in the near future a transition to new, less harmful and more manageable technologies. Today’s strategy for the development of civilization is primarily based on the technocratic approach that places man and his technology above all 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 typical for most people, including people with power-holders and politicians. These people do not understand that the progress of civilization is limited by the ecological imperative – the unconditional dependence of man on the state of living nature. The enormous scale of the economic activities of the countries of the world, the colossal amount of extraction and processing of natural resources require significant environmental costs in modern conditions. Although the size of the air basin of our planet is enormous, mankind is concerned about the problem of air pollution for the following reasons: – over time, the amount of air polluting substances accumulates; – the substances polluting the atmosphere are distributed unevenly, and in some places their concentration is now unacceptably high; – even very small concentrations of certain substances are dangerous. Industrial enterprises and transport are the main sources of air pollution. Heating and industrial boiler houses pollute the city air to a large extent. The enterprises of the fuel and energy complex, including the oil refining and petrochemical industries, are the largest source of environmental pollution in the industry. Ferrous metallurgy is a source of air pollution due to the content of toxic carbon monoxide in the off-gas (waste gases are a valuable fuel that is purified and used in metallurgical plants, but because of the large volume of obsolete fixed assets, metallurgy continues to pollute the environment). In addition, iron ores contain sulfur compounds, 6

therefore sulfur dioxide SO2 is contained in the off-gases of iron and steel enterprises. Any metallurgical industry, as a rule, is the industrial center around which large settlements with a high population density grow. The problem of atmospheric pollution in such localities is always unavoidable, the environmental hazards of metallurgical enterprises are usually aggravated by a large volume of production. Enterprises of the petrochemical industry, working in the regular mode, inevitably pollute the atmospheric air and natural waters. 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. Many industrial enterprises, in the absence of appropriate cleaning methods, pollute the air with odorous or combustible compounds. So, for example, waste gas in the production of bitumen or asphalt contains impurities used in the process of aldehydes and odorous substances. When formaldehyde is obtained, some combustible materials remain in the off-gases. In lithographic and printing shops, air is polluted with solvent vapors and resinous substances. In the production of phthalic anhydride, small amounts of the initial compounds remain in the exhaust gas. 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 total amount of emission of greenhouse gases fall to the share of the petrochemical enterprises. 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. All the 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 1 kg of gasoline absorbs from the air 3.5 kg of oxygen, the reaction of oxidation of products of world oil production during the year absorbs about 12 billion tons of oxygen from the atmosphere. Combustion of natural gas produced per year absorbs from the atmosphere more than 11 billion tons of oxygen. It is no accident that 7

in the air of megacities only 17% of oxygen is contained in place of natural 21%. Therefore, air pollution causes much more concern than any other type of environmental destruction. In 1972 in Stockholm (Sweden) for the first time the United Nations Conference on the problems of the environment concerning the relationship between economic development and environmental degradation was held. After the Conference, the governments established the United Nations Environment Program (UNEP), which remains the world’s leading agency on environmental issues. International, intergovernmental and in-country scientific conferences and symposia, meetings and seminars on scientific principles of rational use and conservation of nature are held all over the world. Countries unite their efforts and begin to cooperate in the field of the environment. The enormous scale of the economic activities of the countries of the world, the colossal amount of extraction and processing of natural resources require significant environmental costs in modern conditions. The concept of sustainable development proclaimed by the international community is a conceptual base for development the international and national politician in the field of the environmental management and environmental protection considering close interrelation of nature protection activity with economy and the social sphere now. 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). The monograph deals with the environmental impact of sources of technogenic (man-made) emissions into the atmosphere. From year to year, the content of carbon dioxide in the atmosphere increases. This leads to the so-called «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. The pollution of the atmospheric air is of great concern, than any other kind of destruction of the natural environment. The proposed monograph discusses the problems of global warming, the efforts of the world community to reduce the impact of technogenic emissions on flora, fauna and human health, the 8

chemistry of the processes of transformation of pollutants. Various methods of purification from technogenic emissions into the atmosphere are described. Among the known methods of utilization and neutralization of harmful emissions of industry and vehicles, the most effective is the deep catalytic oxidation of organic substances to carbon dioxide and water. The cost of produced gas cleaning catalysts in the world is more than 2.2 billion dollars a year, catalysts for refining ~ 2.0 billion dollars a year, and catalysts for the chemical industry – 3.9 billion dollars per year. Most of the world’s platinum (100 tons/year) is used for the preparation of gas cleaning catalysts. That’s why the monograph describes in detail the catalytic methods of purification. The author collected and systematized the data published in modern domestic and foreign sources. In the monograph there are also materials of the multi-year researches of the author on catalytic purification of off-gases of the industry and motor transport. The monograph is intended for researchers working in the field of ecology, catalysis, oil and gas, chemical technology of organic substances, oil refining, petrochemistry; bachelors, masters and doctoral students studying in the specialties «Chemistry», «Petrochemistry», «Chemical Technology of Organic Substances», «Chemical Technology of Inorganic Substances», students, undergraduates and doctoral students.

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Chapter 1. THE BASIC CONCEPTIONS AND TERMS     1.1. Technogenic impact on the environment 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 favor by nature, take them from it is our task». 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 activity of 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 [1-4]. Anthropogenic impact began to be felt at the global level. So, today for every inhabitant of our planet there are about 400 tons of annually moved rock and 2 m2 of the newly disturbed earth’s surface. The total mass extracted and processed by mankind of mineral raw materials 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 exceeds the volume of matter entering the surface by the same amount 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 groundwaters, soil cover, changes in moisture exchange between the Earth’s surface and the atmosphere. The chemicals created by the person in increasing number collect on the land surface, in the atmosphere and the water environment, exerting harmful impact on a terrestrial biota. There is also an increase in speed of loss of a biodiversity. Today F. Engels’s warning that «it isn't necessary to be under a delusion with victories over the nature because for each such victory the nature revenges the person that each 10

of these victories has, besides those prime consequences on which the person expects as well absolutely other, unforeseen consequences which often destroy value of the first» is very relevant. The enterprises of the fuel and energy complex, including the oil refining and petrochemical industries, are the largest source of the environmental pollution in the industry. Enterprises of the petrochemical industry, working in the regular mode, inevitably pollute the atmospheric air and natural waters. 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. 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 total amount of emission of greenhouse gases fall to the share of the petrochemical enterprises. 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 production 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 [5-9]. 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 11

shafts, reservoir breathing valves, open surfaces of treatment plants. Refining related to the production and use of substances with a number of specific properties (explosiveness, flammability, toxicity), which is often caused by 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. All the 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 1 kg of gasoline absorbs from the air 3.5 kg of oxygen, the reaction of oxidation of products of world oil production during the year absorbs about 12 billion tons of oxygen from the atmosphere. Combustion of natural gas produced per year absorbs from the atmosphere more than 11 billion tons of oxygen. It is no accident that in the air of megacities only 17% of oxygen is contained in place of natural 21%. Therefore, air pollution causes much more concern than any other type of environmental destruction [8-12]. Modern environmental problems of the Republic of Kazakhstan are complex, diverse and territorially differentiated. On emissions of harmful substances from stationary sources into the atmosphere Kazakhstan is among the three leaders after Russia and Ukraine (amongst CIS countries). In the industry of Kazakhstan, the level of use of toxic substances is at a low level. Pollution of the air basin by toxic emissions of enterprises leads to high incidence of the population, low life expectancy and degradation of the surrounding nature. The level of air pollution due to the development of industry and vehicles has increased dozens of times from year to year. The greatest threat to the health of the population is the exhaust gases of road transport, which contain a number of toxic components (carbon monoxide, nitrogen oxides, carcinogenic substances, etc.), the concentration of which in the streets with heavy traffic exceeds the sanitary standards many times over. This is especially harmful for cities with poor natural ventilation, such as Los Angeles, Almaty, Pavlodar, Istanbul. Smogues are a common phenomenon over London, Paris, Los Angeles, New York and other cities in Europe and America. By their physiological effects on the human body, they are 12

extremely dangerous for the respiratory and circulatory system and often cause premature death of urban residents with weakened health. A quarter of the generated smog-forming nitric oxides and half of the highly dispersed soot are accounted for by road machinery, airplanes, cars [13-17]. In Kazakhstan, on a national scale, the share of motor vehicles in total emissions of pollutants into the atmosphere by all technogenic sources reaches on average 40%, in the mass of industrial waste – 2%. The increased content of toxic components in exhaust gases creates serious obstacles to the use of equipment with diesel drive in underground mines. The experience of operating diesel engines abroad indicates the significant advantages of trackless selfpropelled equipment in comparison with the electric drive (labor productivity is increased, the cost of ore extraction is reduced, etc.). The main direction of a solution of the problem of ecological safety should be considered greening of chemical productions, i.e. creation of environmentally friendly, waste-free, more precisely, lowwaste technological productions in which all components of raw materials and energy are most rationally and in a complex used and normal functioning of the environment and natural balance aren’t broken. 1.2. The major technogenic catastrophes of XX-XXI centuries The technogenic catastrophe is a major accident at an industrial site, entailing a massive loss of life and even an ecological catastrophe. One of the features of man-made disasters is their accident, randomness (in this they differ from terrorist acts). Usually technogenic are opposed to natural disasters. However, like natural, man-made disasters can cause panic, traffic collapse, and lead to an upsurge or loss of authority [18-21]. Every year in the world dozens of technogenic disasters of different scale occur. We list here a few of the largest technogenic disasters that occurred in the 20-21 centuries. December 6, 1917 there was an explosion in the bay of the Canadian city Halifax. The French military ship «Mont Blanc», bound for France, collided with the Norwegian ship «Imo». The problem was that the «Mont Blanc» was filled with explosives to the brim, and the force of the explosion was enough to destroy half the town. Died two thousand, nine thousand injured. 13

The explosion at the chemical plant in Oppau, Germany was on September 21, 1921 (fig.1). At the plant where the disaster happened, a month earlier, an explosion had already erupted, killing a hundred people. But the measures were not taken, and the next accident claimed the lives of 600 employees and random people, wounding several thousand. 12 tons of a mixture of sulfate and ammonium nitrate exploded with the force of 5 kilotons of TNT, literally wiping the town off the face of the earth [22]. The accumulation of toxic components of exhaust gases of motor vehicles and tail gases of chemical plants and heating systems in moist air causes catastrophic disasters for the population. For example, in Belgium in 1930, mass damage of the respiratory tract and mucous membranes of the inhabitants was noted; the mortality rate in this period was 10.5 times higher than expected in normal conditions. A similar phenomenon was also observed in Pennsylvania, in the eastern part of the United States (Donora) in 1948. Within five days, smoke from coal burning and factory emissions in London (December, 1952) covered a territory with a dense layer. The fact is that the cold weather has come and the inhabitants have begun to heat the stoves with coal in order to warm the houses. The combination of industrial and public emissions into the atmosphere resulted in thick fog and poor visibility, and 12,000 people died from inhalation of toxic fumes. The same accident was in the Ruhr area in 1962. Frequent smog affects the inhabitants of Los Angeles. Very often, as a result of the release of large amounts of hydrocarbons, fogs are formed, especially in places with a high content of soot and moisture in the air. For the same reason, in deep quarries of open-cast mining (depth up to 200 m and above), vehicles sometimes stand idle for 10-12 shifts. In the case of a violation of natural air exchange, the pollution exceeds the permissible sanitary standards, for example, aldehydes at the bottom of the quarry 30-40 times. April 26, 1942 there was an explosion in the coal mine Benxihu (China). The Chinese mine of Benxihu during the Second World War was under Japanese rule, and the miners were treated like slaves. Because of the extensive leakage of gas, an explosion was blown up, killing 1,500 people. The workers needed a week to take out all the dead from the mine.

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Figure 1 – An accident at the chemical plant in Oppau, Germany, September 21, 1921

On March 25, 1947, an explosion occurred in a coal mine in Centralia, Illinois, USA. It was then that at the local mine an explosion of coal dust buried more than a hundred people – one instantly died under the rubble, others – from toxic smoke. The United States in March 1954 carried out a test explosion of nuclear weapons in the Bikini Atoll, located near the Marshall Islands. It was a thousand times more powerful than the explosion on Hiroshima, Japan. This was part of the experiment of the US government. The damage caused by the explosion in Castle Bravo (March 1, 1954) was disastrous for the environment on the area of 11,265.41 km2. 655 representatives of the fauna were destroyed. June 21, 1957 at the plant in Karaganda (Kazakhstan) there was an explosion at the plant number 4D. The reason was a violation of the production technology, there was a fire in the mixing workshop of the components of the future explosive. As a result of the ensuing explosion, 33 people were killed. Industrial catastrophe near Milan, Italy, occurred as a result of the release of toxic chemicals into the environment (fig.2). During the production cycle in the production of trichlorophenol, a hazardous cloud of harmful compounds entered the atmosphere. The release immediately acted fatal to the flora and fauna of the territory adjacent 15

to the plant. The company for 10 days hid the fact of the leakage of chemicals. Cases of cancer have increased, which was subsequently proven by studies of dead animals. The inhabitants of the small town of Seveso began to develop frequent cases of cardiac pathologies, respiratory diseases [23].

Figure 2 – Disaster in Seveso (July 10, 1976)

The Bhopal catastrophe (fig.3) was the largest in terms of the number of victims of a technogenic catastrophe in modern history that occurred as a result of an accident at a chemical plant owned by the American chemical company Union Carbide and located in the Indian city of Bhopal (the capital of the state of Madhya Pradesh) early in the morning December 3, 1984 year. This catastrophe resulted in the death of at least 18 thousand people, of which 3 thousand died directly on the day of the accident, and 15 thousand – in subsequent years. In 1970, the Government of India began to pursue a policy of attracting foreign investment in local industry. Union Carbide Corporation (UCC) received permission to build a plant in Bhopal for the production of pesticides for agriculture. The plant was built by a subsidiary of Union Carbide India Limited (UCIL). Initially, it was 16

planned that for the production of pesticides the plant will import part of the chemicals produced by UCC. But, trying to compete with other chemical plants, the plant in Bhopal moved to more complex and dangerous production. Crop failures in India in the 1980s reduced the demand for factory products and it was prepared for sale in July 1984. However, the buyer was not found and work at the plant continued on equipment that by that time already did not comply with safety standards [24-30]. Plant Union Carbide produced a popular at that time insecticide Sevin (carbaryl, 1-naphthyl-N-methylcarbamate). This insecticide is produced by the reaction of methyl isocyanate with α-naphthol in the carbon tetrachloride medium. Methylisocyanate (hereinafter MIC) was stored at the plant in three partially buried in the tanks, each of which could hold about 60,000 liters of liquid.

Figure 3 – The Bhopal catastrophe

The immediate cause of the tragedy was the accidental release of methyl isocyanate vapor, which in the factory tank was heated above the boiling point (39°C), it led to an increase in pressure and rupture of the emergency valve. As a result, from 0:30 to 2:00 on December 3, 1984, about 42 tons of toxic fumes were thrown into the atmosphere. A cloud of methyl isocyanate covered the nearby slums and the railway station (located 2 km from the enterprise). A large number of victims is due to the high population density, untimely information of the population, shortage of medical staff, and unfavorable weather conditions – a cloud of heavy vapors was carried by the wind. Residents of the areas closest to the plant woke up from a disgusting smell. Then was started burning in their eyes. Then some of them told 17

the BBC correspondent that the feeling was as if «someone burned a lot of hot pepper». In just a few minutes, the burning sensation became more painful, and the stink intensified. People began to complain of shortness of breath, many started vomiting. People fell to the ground, foam came from their mouth. Many could not open their eyes. Then, more than 30 years ago, the BBC reported that panic began in the city and surrounding areas, tens of thousands of people tried to leave the contaminated quarters as soon as possible. According to various reports, the total number of victims is estimated at 150,000600,000 people, of which 3,000 died directly at the time of the disaster, another 15,000 – in subsequent years died from the effects of chemicals on the body. These figures give grounds to consider the Bhopal tragedy as the world’s largest man-made disaster by the number of victims [31-34]. The largest accident in the history of nuclear energy, which became a kind of symbol of man-made disasters was the Chernobyl accident, April 26, 1986 (fig. 4). The destruction was explosive, the reactor was completely destroyed, and a large number of radioactive substances were emitted into the environment. The accident is regarded as the largest in its kind in the history of nuclear energy, both in terms of the estimated number of people killed and affected by its consequences, and economic damage. During the first three months after the accident, 31 people died; the long-term effects of irradiation, identified over the next 15 years, have caused the deaths of 60 to 80 people [35, 36]. 134 people suffered radiation sickness of one degree or another. More than 115,000 people from the 30-kilometer zone were evacuated [35]. To eliminate the consequences, significant resources were mobilized, more than 600,000 people participated in the elimination of the consequences of the accident. The highest radiation doses were received by emergency workers and personnel on site, some of the workers, emergency and recovery workers («liquidators») [36-38]. Unlike the bombing of Hiroshima and Nagasaki, the explosion resembled a very powerful «dirty bomb» – the main damaging factor was radioactive contamination. The cloud formed from the burning reactor carried various radioactive materials, primarily radionuclides of iodine and cesium, for the most part in Europe. The largest fallout was recorded in significant areas in the Soviet Union located near the reactor and now referring to the 18

territories of the Republic of Belarus, the Russian Federation and Ukraine [39, 40]. So, hundreds and thousands of people suffered from the effects of irradiation, and huge areas on the territory of Ukraine and Belarus became unfit for life for many years.

Figure 4 – Chernobyl accident, April 26, 1986

In Atyrau oblast (Kazakhstan, USSR) in 1985, a fire broke out in an oil field, which was extinguished with great effort. «This accident occurred on June 25, 1985. During the passage of well No. 37, laid down to refine the Tengiz field and assess oil and gas reserves, an accident occurred at a depth of 4,467 meters and oil and gas were released into the atmosphere. A few hours later, an open fountain of oil and gas caught fire», recalled academician Muftah Diarov [41]. As a result of the accident, a giant fire pillar broke out of the earth, 300 meters high and 50 meters wide. The temperature around the borehole reached 1,500 ºC, the surrounding soil turned from colossal heating into vitreous mass. Eyewitnesses who participated in the extinguishing of the 37th well, described what they saw as a terrible apocalyptic picture. «A terrible roar and stench was almost a kilometer away from the well, the fire devoured everything: tons of water, metal, 19

the technology melted like plastic, periodically the masses of fried meat fell from the sky – there were killed the flocks of migratory birds attracted by fire», eyewitnesses recalled. To extinguish a burning well, the Soviet Union threw the best minds, forces and equipment. The fire was extinguished for 398 days – from June 23, 1985 to July 27, 1986. When the accident was eliminated, there were human casualties. It was tried many ways to extinguish the flame – from the air, from under the earth. They offered to throw it off the sky or drag it along the ground to the mouth of a burning bore hole, like a lid, a multi-toned steel naslepka. As a result, after a year, well No37 was able to be damped by a directed explosion from the inside. The accident at Tengiz disrupted the plans to increase oil production in Kazakhstan from 18.7 million tons in 1981 to 25 million tons in 1985 and exacerbated the continued decline in 1985 oil production in the USSR. «As a result of the accident in Tengiz, 3.4 million tons of oil, 1.7 billion flammable gases, 850 tons of mercaptans and 900,000 tons of soot were thrown into the atmosphere. The morbidity of the population of the Atyrau region has grown by 50 %, and similar accidents are quite expected and also dangerous, especially when oil tanks are opened, which are at great depth and under extreme conditions», academician Muftah Diarov wrote. Explosions and the fire at the plant of the PEPCON company is a large technogenic catastrophe which happened in the city of Henderson, State of Nevada, USA, on May 4, 1988. The fire and the subsequent explosions led to death of two and wounds of 372 people, at the same time damage approximately for 100 million dollars was caused. The majority of the valley of Las Vegas in a radius of 16 km (10 miles) from the plant was treated to explosion action (it is broken out by 10 thousand). Power of explosions was 250 tons in a trotyl equivalent [42, 43]. The PEPCON plant, located in Henderson, Nevada, 10 miles from Las Vegas, was one of two American manufacturers of ammonium perchlorate used as an oxidizer in solid-propellant rocket engines installed in including the Space Shuttle. In addition to the production of ammonium perchlorate, the plant also produced other chemicals. A gas pipeline of high pressure gas and a transmission line under it also ran along the territory of the plant. 20

Due to the suspension of the Space Shuttle program in January 1986 due to the Challenger shuttle disaster, the surplus product that was to be used to launch space shuttles and that was owned by the US government or its contractors was to be stored at the PEPCON plant. In view of this, PEPCON had a stock of ammonium perchlorate stored right on site. In addition, the plant also had current reserves of ammonium perchlorate produced, totaling about 4,500 tons of finished products in plastic and steel containers. Near the plant there were also some auxiliary manufactures. The nearest residential buildings were 3 km from the factory. The fire at the plant arose between about 11:30 and 11:40 on May 4, 1988. Then the fire spread to 55-liter plastic containers inside the warehouse containing products of production. Initially, the factory employees tried in vain to extinguish the fire inside the building, pouring them from the hoses with water. The first of a series of explosions, occurred about 10-20 minutes after the outbreak of fire, and the staff began to flee or leave on the machines from what was happening. Then the chain reaction of explosions and fires began at the plant. In the process, the main gas pipeline was also damaged, and the whole area was enveloped in flames. The fire and explosions lasted several hours. Two of the most powerful of the explosions occurred were seismic waves with a strength of 3.0 and 3.5 points on the Richter scale. According to subsequent estimates, the total energy of the explosions was approximately 1.0 kilotonnes in TNT equivalent. The release of oil from the Exxon Valdez tanker is a crash of the Exxon Exxon tanker Exxon Valdez. The accident occurred on March 23, 1989 off the coast of Alaska [44]. As a result of the disaster, about 10.8 million gallons of oil (about 260 thousand barrels or 40.9 million liters) spilled into the sea, forming an oil spill of 28,000 square kilometers. In total, the tanker carried 54.1 million gallons of oil. It was contaminated with oil about 2,000 kilometers of coastline. This accident was considered the most destructive for the ecology of the catastrophe that ever occurred at sea until the accident of the drilling rig DH in the Gulf of Mexico on April 20, 2010. The area of the accident was hard to reach (it can only be reached by sea or helicopters), which made it impossible for the service and rescuers to react quickly. This area was inhabited by salmon, sea otter, seal and

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many sea birds. During the first days after the accident, oil covered a huge area in the Strait of Prince Wilhelm. On May 20, 1989, at the «Alma-Ata-2» railway station in Almaty Kazakhstan, the USSR two manned cargoes collided at maneuvers. In one of them was a liquefied gas. Gas flowing out of the broken tank broke out. The explosion shook the metropolis. 13 residential houses flared up. A huge gas burner gradually began to heat the next tank. The fighters of the local fire brigade who fought against the fire killed almost everything. But they did not let the rest of the team explode. They were able to cool the neighboring tanks and drive them to a safe place. The number of victims in that fire was estimated in dozens – mostly local residents [45]. The railway accident near Ufa is the largest railway accident in the history of Russia and the USSR that took place on June 4, 1989 in the Iglinsky district of the Bashkir ASSR, 11 km from the city of Asha (Chelyabinsk region, Russia) on the Asha-Ulu-Telyak stretch. At the moment of passing the two passenger trains No. 211 NovosibirskAdler and No. 212 Adler-Novosibirsk, a powerful explosion of a cloud of light hydrocarbons occurred as a result of an accident on the nearby pipeline Siberia-Ural-Povolzhye (fig.5). About 600 people died, 181 of them were children, more than 600 were wounded. Another of the known technogenic disasters is an explosion at the Phillips Petroleum Company's chemical plant, October 23, 1989, in Pasadena, Texas, USA (fig.6). Due to oversight of the employees, there was a larger leak of combustible gas, and there was a potent explosion that is equivalent to two and a half tons of dynamite. The firemen took more than ten hours to extinguish the flames. 23 people died, another 314 were injured. During the military conflict in the Persian Gulf in 1991 in Kuwait, Saddam Hussein set fire to 600 oil wells to create a poisonous smoke screen for as long as 10 months (fig.7). It is believed that 600 to 800 tons of oil burned daily. About 5% of Kuwait’s territory was covered with soot, livestock was dying of lung disease, and the number of cancer cases increased in the country [47].

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Figure 5 – The railway accident near Ufa, Russia, 1989 [46].

Figure 6 – An explosion at the Phillips Petroleum Company’s chemical plant, October 23, 1989, in Pasadena, Texas

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Figure 7 – Oil fires in Kuwait (January/February 1991)

In July 2000, more than a million gallons of oil flowed into the Iguazu River in Brazil as a result of the catastrophe on the oil refinery platform (about 3,180 tons). The resulting spot moved along the river, threatening to poison the drinking water at once for several cities. The liquidators of the accident built several barriers, but the oil could not be stopped until the fifth. One part of the oil was collected from the surface of the water, the other went through specially constructed drainage ducts. The company Petrobrice paid $ 56 million in fine to the state budget and 30 million to the state budget. September 21, 2001 in the French city of Toulouse at the chemical plant AZF (fig.8) there was an explosion, the consequences of which are considered one of the largest man-made disasters. Exploded 300 tons of ammonium nitrate (salt of nitric acid), which were in the warehouse of finished products. According to the official version, the leadership of the plant is guilty, which did not ensure the safe storage of an explosive substance. The consequences of the disaster were enormous: 30 people died, the total number of wounded was more than 3,000; thousands of houses and buildings were destroyed or damaged, including almost 80 schools, 2 universities, 185 kindergartens, 40,000

24

people without a roof over their head 130 enterprises actually ceased their activities. The total amount of damage is 3 billion euros. On November 13, 2002, near the coast of Spain, the Prestige oil tanker fell into a heavy storm, in its holds there were more than 77,000 tons of fuel oil. As a result of the storm, a crack in the ship’s hull formed about 50 meters long. On November 19, the tanker broke in half and sank. As a result of the disaster, 63,000 tons of fuel oil fell into the sea. Purification of the sea and shores from fuel oil cost $ 12 billion, complete damage to the ecosystem cannot be estimated. On August 26, 2004, near the city of Cologne in the west of Germany, a petrol tanker carrying 32,000 liters of fuel fell from a Wiehltal bridge 100 meters high. After the fall, the petrol tank exploded. The culprit of the accident was a sports car, which skidded on a slippery road, which caused the drift of a gasoline tank truck. This accident is considered one of the most costly man-made disasters in history – temporary repair of the bridge costs $ 40 million, and a complete reconstruction – $ 318 million.

Figure 8 – An explosion in Toulouse (France) at the chemical plant AZF in 2001

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On November 13, 2005, several powerful explosions thundered at the Zilin Chemical Plant, China (fig.9). A huge amount of benzene and nitrobenzene was released into the environment, which has a harmful toxic effect. The disaster led to the death of six people and wounding seventy [47].

Figure 9 – Explosion at the Ziulin Chemical Plant (November 13, 2005)

On March 19, 2007, due to a methane explosion at the mine «Ulyanovskaya» in the Kemerovo region (Russia), 110 people were killed. After the first explosion in 5-7 seconds followed by four more, which caused extensive collapses in the workings in several places at once. The chief engineer and almost all management of the mine died. This accident is the largest in the Russian coal mining for the last 75 years. On July 16, 2007, a phosphorous accident occurred near Lviv, Ukraine. The railway accident was not far from the village of Ozhidov in the Busk district of the Lviv region of Ukraine (fig.10). At the 12th kilometer of the Ozhidov-Krasnoe Passage, a train derailed from Kazakhstan to Poland, 15 wagons with yellow phosphorus rolled over, six of them caught fire, and the fire was extinguished at 11:29 pm

26

Moscow time on the day of the accident. About 500 firefighters and 220 police officers were involved in extinguishing the fire [48-52].

Figure 10 – A phosphorous accident occurred near Lviv, Ukraine, 2007

As a result of the fire, 16 people were poisoned with combustion products, 13 of which were seriously and severely hospitalized in the military medical clinical center of the Western Operational Command in Lviv. There were no dead people. In the morning of the next day, residents of the Bus district began to contact medical institutions complaining of nausea and headache. Residents of the nearest villages were temporarily evicted. July 17, in connection with the reaction of phosphorus with air, the fire continued in small foci not covered with foam. Firefighters continued to pour foam on the crash site. On July 19, they began to lift and ship the surviving cisterns with phosphorus. In total, 152 people (of them 27 children) were hospitalized since the beginning of the emergency [53]. The explosion of the Deepwater Horizon oil platform is an accident (explosion and fire) that occurred on April 20, 2010, 80 kilometers from the coast of Louisiana in the Gulf of Mexico on the Deepwater Horizon oil platform at the Macondo field (fig.11). The oil 27

spill following the accident became the largest in the history of the United States and turned an accident into one of the largest man-made disasters due to the negative impact on the ecological situation. At the time of the explosion at the Deepwater Horizon installation, 11 people were killed and 17 of the 126 people on board were injured [54]. At the end of June 2010, there were reports of the death of two more people in the aftermath of the disaster [55]. Through the damage to the well pipes at a depth of 1,500 meters, about 5 million barrels of oil spilled into the Gulf of Mexico in 152 days, the oil slick reached 75,000 km2 [56], which is about 5% of the area of the Gulf of Mexico.

Figure 11 – Explosion of the oil platform Horizon Oil (April 20, 2010)

On October 4, 2010, a major environmental disaster occurred in western Hungary. At the aluminum plant, the explosion destroyed the reservoir dam with poisonous waste – the so-called «red mud». About 1.1 million m3 of caustic substance was flooded with a 3-meter flow of the city of Kolontar and Dechever, 160 kilometers west of Budapest. Red mud is a precipitate that forms during the production of aluminum oxide. Upon contact with the skin, it acts on it as an alkali. As a result of the disaster, 10 people were killed, about 150 received various injuries and burns. On March 11, 2011 in the north-east of Japan at the Fukushima1 nuclear power plant, after the strongest earthquake, the biggest accident in the last 25 years after the Chernobyl catastrophe occurred (fig.12). Following the tremors in magnitude 9.0 on the coast came a huge wave of tsunami that damaged 4 of the 6 reactors of the nuclear power plant and disabled the cooling system, which led to a series of hydrogen explosions, melting the core.

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Total emissions of iodine-131 and cesium-137 after the accident at the Fukushima-1 nuclear power plant amounted to 900,000 terabekkereles, which does not exceed 20% of the emissions from the Chernobyl accident in 1986, which amounted to 5.2 million terabekkereles. The total damage from the accident at the NPP «Fukushima-1» experts estimated at 74 billion dollars. Complete elimination of the accident, including the dismantling of reactors, will take about 40 years. July 11, 2011 at a naval base near Limassol in Cyprus there was an explosion that took 13 lives and put the island state on the brink of economic crisis, because of destroying the island’s largest power plant. The investigators accused the President of the Republic Dimitris Christofias that he neglected the problem of storing ammunition confiscated in 2009 from the Monchegorsk vessel on suspicion of smuggling weapons to Iran. In fact, ammunition was stored right on the ground in the territory of the naval base and detonated because of the high temperature.

Figure 12 – Accident in Fukushima (March 11, 2011)

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On February 28, 2012, an explosion took place at a chemical plant in the Chinese province of Hebei, killing 25 people. The explosion occurred in the workshop for the production of nitroguanidine (it is used as a rocket fuel) at the Hebei Keer Chemical Plant in Shijiazhuang City. April 18, 2013 in the American city of West Texas fertilizer factory was a powerful explosion (fig.13). Almost 100 buildings in the district were destroyed, from 5 to 15 people were killed, about 160 people were injured, and the town itself looked like a war zone [57]. July 6, 2013 there was a collapse of the composition with oil in Lak-Megantik (Canada). The catastrophe occurred in the east of the Canadian province of Quebec. The train, carrying seventy tanks with crude oil, fell off the rails, and the tanks exploded. More than half of the buildings in the city center were destroyed by an explosion and a subsequent fire, about fifty people were killed (fig.14).

Figure 13 – Explosion at the plant of fertilizers in the city of West (USA), 2013

On August 12, 2015, as a result of a security breach in the storage of explosives in the Chinese port, two explosions of great power were thundering, which led to a large number of casualties, to hundreds of destroyed houses and to thousands of destroyed vehicles.

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Figure 14 – The collapse of the composition with oil in Lak-Megantik (Canada), July 6, 2013

1.3. Ecological consequences of the activities of enterprises for processing hydrocarbon-containing raw materials The main feature of the enterprises for processing hydrocarbon raw materials is the presence of fire and explosion hazard 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 tab.1, 2 statistical data on 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 processing of hydrocarbon feedstock are in most cases due to leaks of combustible liquid or hydrocarbon gas [58].

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Table 1 – Major accidents at the enterprises for processing of hydrocarbonic raw materials

Place

Substance, nature of accident

Germany, Ludwigshafen Germany, Ludwigshafen

Explosion of a cloud of butadiene and butylene Explosion of a cloud of dimethyl ether Explosion of the storage of France, Faisen liquefied petroleum gas United States, Port Explosion of the storage of Hudson liquefied petroleum gas South Africa, Leakage of liquid ammonia from Potchefstroom the storage United States, Propane leak Decatur Netherlands, Beck Explosion of a cloud of propane England, Explosion of a cloud of Fliksborough cyclohexane USA Propylene emissions Colombia, Catagena Ammonia leak Colombia, SantaExplosion of methane Cruz Explosion of a cloud of Spain, San Carlos propylene Mexico, Mexico Explosion of the tank (liquefied City gas) Brazil, Cubatão Explosion of gasoline Russia, Yaroslavl Explosion of hydrocarbon gases Russia, Explosion of hydrocarbon gases Krasnoyarsk Emission and explosion of Russia, Россия, Ufa hydrocarbon gases

Emission, t

Number Number of of deaths injured

20

57

439

30

207

300

200

18

81

70

0

7

-

18

64

63

7

152

3-5

14

107

30-50

28

89

5.5 -

14 30

45 22

-

52

-

38

215

780

-

452

5,250

3.3

500 6

7,000 13

-

4

5

-

2

8

The negative role of technogenic pollution considerably affects human health. According to statistical data, owing to technogenic air pollution health of the population worsens for 43-45%. Therefore for such productions environmental protection and increase in industrial safety should become priority activities [21].

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Table 2 – Direct economic losses from major accidents at the US refineries City, state Linden, New Jersey Billing, Montana Avon, California Avon, California Baton Rouge, Louisiana Texas City, Texas Texas City, Texas Borger, Texas 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

Installation, process Hydrocracking Alkylation Coking Coking Catalytic cracking Alkylation Alkylation Alkylation Catalytic cracking Alkylation Catalytic cracking Hydrocracking Catalytic cracking Catalytic cracking Hydrocracking Atmospheric-vacuum tube (AVT) Catalytic cracking Hydrotreating Atmospheric-vacuum tube (AVT) Hydrotreating

Direct losses, mln. USD 94.6 14.5 22.9 13.9 18.2 99.6 40.3 53.8 60.7 16.9 327.0 100.7 53.0 26.3 15,8 27.5 23.5 51.0 15.3 72.7

In fact the impact on megacities at application of hydrocarbon systems is manifested in two ways. First, from the motor transport side – 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, particulate (PM), 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

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systems, including oil refining and petrochemical industries, were in the urban metropolitan areas. 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 in the territories of oil refineries and oil depots contribute to soil contamination and the 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 the combustion of oil residues, as well as products of incomplete combustion – soot, polycyclic aromatic hydrocarbons (PAH), etc., enter the atmosphere from petrochemical facilities. On degree of ecological danger the pollutants which are most often found in sources of emissions pollutants in objects of oil industry may be arranged in the following decreasing sequence (1): H2S  CnH2n+2 SO2 SO3 NO  NO2 CO  NH3 CO2 (1) Fight with such emissions is hampered by the fact that they come from a huge number of sources dispersed 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 on 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.

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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 the formation of explosive mixtures, but also their ignition. The distribution of the number of accidents by certain types of technological equipment is presented in tab.3. Very topical is the detection of the gassed air environment of the territory of enterprises in the early stages of the accident [13]. 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. Table 3 – 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

On the accepted technology of processing sulphurous oil in the course of catalytic hydrotreating hydrogen sulfide and other sulphurous compounds are extracted in the form of commodity products – sulfur or sulfuric acid and emission of hydrogen sulfide in the atmosphere is considerably excluded. 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 trap. Dust is formed during the transportation of catalysts and adsorbents, their 35

regeneration, grinding, drying, etc. When carrying out processes in fluidized bed reactors (catalytic cracking, dehydrogenation of butane), the catalyst particles in case of repeated use are reduced in size and are taken out with the gas flow. In oil refineries for the removal of dust particles apply dust precipitation chambers, cyclones, rotary apparatus. Measures to protect the air basin in oil refineries 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 [59]. 1.4. Implementation of environmentally friendly technological processes It is necessary to distinguish the following main directions [21, 60] 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 be carried out with minimum energy and fuel consumption 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 processes of separation; – use of the active and selective catalysts allowing to carry out processes at the lowered temperature and pressure;

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– the 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 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 the formation of thermal emissions into 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 that can be recycled or disposed of by 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. Ensuring high operational reliability, tightness and durability of functioning of the equipment and all systems of productions. Minimizing or exception of probability of accidents, explosions, fires and emissions of toxic agents in environment. Development of the automated systems of ensuring ecological safety of productions and complexes. 6. Ensuring 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, oxygencontaining 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 37

cities, while simultaneously significantly expanding the resources of motor fuels. 1.4.1. Development of wasteless and low-waste technology in the selected industries The main directions for implementation of wasteless and lowwaste technologies on an example of selected industries [1-5, 18-21]: 1. Power Engineering It is necessary: – greater use of new methods of fuel combustion, for example, such as fluidized bed combustion, which helps to reduce the content of pollutants in the waste gases; – implementation of development for purification of gas emissions from sulfur and nitrogen oxides; – to achieve the operation of dust-cleaning equipment with the highest possible efficiency, while the resulting ash is effectively used as raw material in the production of building materials and in other industries. 2. Metallurgy – involvement in processing of gaseous, liquid and solid waste of production, decrease in emissions and dumpings of harmful substances with flue gases and sewage; – widespread introduction of use of large-tonnage dump solid waste of mining and concentrating production as building materials, laying the mines, pavements, wall blocks etc., instead of specially mined resources; – processing in full all blast-furnace and ferro-alloy slags, as well as a significant increase in the scale of processing steel smelting slags and non-ferrous metallurgy slags; – a sharp reduction in fresh water costs and a decrease in wastewater through the further development and introduction of anhydrous technological processes and drainless water supply systems; – increasing the efficiency of existing and newly created processes for capturing by-products from waste gases and sewage; – 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; 38

– utilization of weak (less than 3.5% sulfur) sulfur-containing gases of variable composition by introducing an efficient method at the non-ferrous metallurgy enterprises – oxidation of sulfur dioxide in the nonstationary regime of double contacting; – at the enterprises of non-ferrous metallurgy, acceleration of the introduction of resource-saving autogenous processes, including melting in a liquid bath, which will allow not only to intensify the process of processing raw materials, reduce energy consumption, but also 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; – development and widespread introduction at the metallurgical enterprises of the highly effective cleaning equipment and also devices supervisory of different parameters of impurity of the environment; – the fastest development and deployment of new progressive low-waste and waste-free processes, meaning direct reduction and cokeless processes of of steel production, powder metallurgy, autogenous processes in nonferrous metallurgy and other perspective technological processes directed to reduction of emissions in the environment; – expansion of the 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. 3. 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 the production of biogas from residues of organic products; – methods of radiation, ultraviolet, electropulse and plasma intensification of chemical reactions. 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; 39

– increase in fuel efficiency of vehicles – preferential production of cars of small and especially very small classes, mini-tractors. 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. 1.5. Global warming 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 the expansion of the scale of economic activity and leads to an increase in the anthropogenic pressure 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 is increased, the probability of a loss of stability in the biosphere 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 [61]. The climatic system of Earth includes the atmosphere, the ocean, the land and the biosphere. Conditions of the environments entering this complex system are described by such parameters as temperature, pressure, density, speed of the movement, etc. «Behavior» of the climate system, which is characterized by cyclic processes, can be characterized by more complex parameters: the dynamics of largescale 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. The climate is defined by a set of the statuses passed by climatic system for the characteristic period in several decades and frequency of their recurrence. Climate change at the global level or for this 40

geographical terrain consists in change of the long-term mode of weather. Global climatic, biological, geological, chemical processes and natural ecosystems are closely related: changes in one process can affect others. Important is the interaction between the atmosphere and the ocean, which is the main source of extreme weather events. Since the World Ocean occupies most of the planet, it is the 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 circulation of such powerful ocean currents as the Gulf Stream. There is often feedback between the components of the climate system. With 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 climate change of Kazakhstan. If we believe the presented data, climate warming in Kazakhstan is faster than the world average [62]. So, for example, in 2016 the temperature anomaly was +1.66ºC 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 on the flat 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 every year more often. The main components of the air – nitrogen, oxygen and inert gases – are transparent both for visible sunlight and for 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: 41

– water vapor, – carbon dioxide, – methane, – N2O, – a number of technogenic gases. Greenhouse gases are stored in the atmosphere for quite a long time, the period of their life is estimated for 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 excess inflow over the runoff of these gases and is caused by anthropogenic, 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, there has been no significant deviation of air humidity from the average value wasn’t observed [63]. 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 in a natural carbon cycle. Additional anthropogenic intake of carbon dioxide in the atmosphere could be compensated as a result of the biotic regulation which is carried out 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 land use, the amount of biomass and soil carbon has significantly decreased, and, therefore, the carbon stock accumulated in terrestrial ecosystems as a 42

whole. As a result, a large amount of CO2 has entered the atmosphere. The area of forests decreased sharply, especially in the tropics. Grazing 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 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 actually in the warming, as in the imbalance and destabilization of the climate system. The powerful release of CO2 is a kind of chemical impulse, quite a strong perturbation for the climate system. The longterm process of the natural evolution of the global climate is imposing ever more tangible changes in the climate system caused by anthropogenic activities [64]. 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). Increasing damage caused by natural disasters and estimated in billions of dollars. 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 43

rainfall will increase sharply. The unfavorable redistribution of precipitation will exacerbate the acute problem of providing a number of regions with fresh water. The direct impact of heat stress will be felt in 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 [65]. 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, 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 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 a loss of biodiversity (for example, for mammals of taiga and mountain ecosystems, losses will amount to 10 to 60% of the number of species). In the Arctic, climate change is particularly intense. Compared with the rest of the world in this region, the growth rate of the average temperature is twice as high. The ice sheet melts with unprecedented speed: now it is twice as thin as 30 years ago. If the rate of melting continues, Arctic ice may not remain in summer 2070. The unprecedented speed with which Arctic ice melts can lead to the flooding of significant areas, the disappearance of certain species and the destruction of urban infrastructure. To such conclusions came 250 scientists from different countries, working under the aegis of the Arctic Council [66]. 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 be 44

affected only by some unique and now endangered ecosystems. In any case, there is a risk of an increase in the number of extreme events, and with significant warming it will increase. With a smaller change in the average global temperature, only part of the regions of 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. Industry has to find ways to reduce greenhouse gas emissions, mainly carbon dioxide, to prevent global warming. Reductions in the production of carbon, NOx and particulate matter emissions must be made to comply with current, and new emission standards in order to keep levels within regulated thresholds. Concern for the environment continues to drive the development and application of exhaust aftertreatment wherever internal combustion engines operate [67-69]. 1.6. Principles of the concept of sustainable development The human impact on the state of the world's ecology has now become world-wide. The concept of sustainable development proclaimed by the international community is a conceptual base for development the international and national politician in the field of the environmental management and environmental protection considering close interrelation of nature protection activity with economy and the social sphere now. 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 (CED92) and at the World Summit on Sustainable Development, held in 2002 in Johannesburg (WSSD- 2002). 1.6.1. International Conferences on the environment In 1972 in Stockholm (Sweden) for the first time the United Nations Conference on the problems of the environment concerning the relationship between economic development and environmental degradation was held. After the Conference, the Governments established the United Nations Environment Program (UNEP), which remains the world's leading agency on environmental issues. In 1973, the United Nations Sudano-Sahelian Office (UNSO) was established, which led efforts to combat the spread of desertification 45

in West Africa. However, the decision-making process on this issue was moving very slowly. In addition, the state of the environment was deteriorating, moreover, problems such as global warming, depletion of the ozone layer and water pollution were exacerbated, and the rate of destruction of natural resources was accelerating. In the 1980s, negotiations among Member States on environmental issues were held, including negotiations on treaties for the protection of the ozone layer and control over the movement of toxic waste. Since the mid 80-ies of the last century, measures have been taken to protect the ozone layer of the Earth. In 1985, the Convention for the Protection of the Ozone Layer was adopted in Vienna (Austria). In 1987, the Convention was supplemented by the Montreal Protocol on Substances that Deplete the Ozone Layer [70-72]. The United Nations Conference on Environment and Development was held in Rio de Janeiro (Brazil) on June 3-14, 1992. At the meeting, a declaration was adopted that stated that "in order to achieve sustainable development, environmental protection must be an integral part of the development process and can not be considered in isolation from it. «The Declaration» includes 27 principles that determine the rights and duties of countries in ensuring development and human well-being. The United Nations Conference on Environment and Development, held in 1992 in Rio de Janeiro (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 the development of modern civilization and the 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 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 state sustainable development strategies for most countries of the international community, whose responsibility lies with 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. 46

World Summit on Sustainable Development, held in 2002 in Johannesburg (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; – protecting biodiversity; – 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. The FCCC is laying the foundations for a policy on greenhouse gas emissions management [73]. 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 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 for 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;

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– 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 emissions 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 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 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 emissions of all greenhouse gases; – adoption of national programs containing measures to mitigate the effects of climate change and develop strategies for adequate adaptation to these changes; – cooperation on scientific and technical issues and education and promote education, public awareness and exchange of information related to climate change, etc.

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1.6.2. Kyoto Protocol to the UN Framework Convention. Marrakech Accords 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 Kioto 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 [74]. The highest commitments to reduce emissions were assumed by the countries of the European Union (8%). It is enough for CIS countries 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 by the Kyoto Protocol are not regulated and will be determined by additional international agreements. A list of greenhouse gases 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) and nitrous oxide (N2O), as well as three groups of long-lived industrial gases. It is recommended to carry out «for encouragement of sustainable development» policy and a number of measures for decrease in emissions, such as increase in efficiency of use of energy and assistance to 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 49

the field of reducing greenhouse gas (GHG) emissions using market mechanisms. Between the countries treat such mechanisms of cooperation: 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 implementation 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 countries to participate in the Kyoto mechanisms [75-77]: – 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 the 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 50

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 non-compliance, 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 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. 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. 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. Verification at the international level 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 [78].

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Chapter 2. ENVIRONMENTAL IMPACT OF THE INDUSTRY    2.1. Classification of industries by the degree of environmental hazards As is known from history, the first industrial emission of waste gases into the atmosphere is associated with the emergence of metallurgy. For example, to produce 1 ton of cast iron, 8-10 tons of various loose materials are processed: sand, dry clay, coal dust, etc. The dust emission per 1 ton of pig iron is 4.5 kg, sulfur dioxide 2.7 kg, manganese – 0.5-1.0 kg. Together with the blast-furnace gas, As, P, Sb, Pb compounds, mercury and rare metal vapors, hydrogen cyanide and resinous substances are emitted into the atmosphere. Ferrous metallurgy is a source of air pollution due to the content of toxic carbon monoxide in the off-gas (waste gases are a valuable fuel that is purified and used in metallurgical plants, but because of the large volume of obsolete fixed assets, metallurgy continues to pollute the environment). In addition, iron ores contain sulfur compounds, therefore sulfur dioxide SO2 is contained in the off-gases of iron and steel enterprises. When loading metallurgical furnaces (blast-furnace, converter-open-hearth furnaces) with ore and coke, dust contamination with air is also possible. In addition, during the operation of metallurgical furnaces, sulphides, mercaptans (R-S-H) and other chemicals with an unpleasant odor are released into the air. Any metallurgical industry, as a rule, is the industrial center around which large settlements with a high population density grow. Sinter plants are a significant source of air pollution by sulfur dioxide. During the agglomeration of ore, sulfur burns out of pyrite. Emission of sulfur dioxide gas during agglomeration can be calculated in an amount of 190 kg per 1 ton of ore [8, 60, 79]. Emissions of openhearth and converter steelmaking shops play a significant role in atmospheric pollution. Non-ferrous metallurgy enterprises are also sources of air pollution, for example, sulfur dioxide, which is released during the preparation of raw materials. The problem of atmospheric pollution in such localities is always unavoidable, the environmental hazards of metallurgical enterprises are usually aggravated by a large volume of production. 52

Most industrial enterprises do not keep track of harmful emissions or perform it very inaccurately. In some case it is not known what harmful substances come from an industrial facility. The approximate composition of products in industrial gaseous emissions is given in Table. 4. For definition of the classification of industries by the degree of environmental hazards the following characteristics were considered: – variety of emissions of the enterprises of branch; – volumes of emissions; – class of toxicity of emissions. The coefficient of toxicity of emissions was calculated on the basis of the listed characteristics. For its calculation, the following formula is proposed (2):

,

(2)

where Tc is a toxicity coefficient Ci – MAC (Maximum Allowable Concentration) of the emitted ith substance by industry; Mi – the volume of emissions of a substance; n is the number of substances emitted. Analysis of these indicators allows to subdivide industries by the degree of emission toxicity (tab.5) into four groups [80]. In non-ferrous metallurgy, the main danger is the emissions of compounds highly toxic metals such as copper, lead, mercury, cadmium, zinc, and a large number of calcined gases containing sulfur compounds (predominantly SO2), fluorine and its derivatives. Table 6 presents data on the emission of certain elements in non-ferrous metallurgy.

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Table 4 – Types of production of technological products and chemical composition of gaseous waste No Type of production 1 Oil refining 2 3 4 5 6 7 8 9

Chemical composition of gaseous waste Mercaptans, hydrogen sulphide, ammonia, organic nitrogen compounds, carbon monoxide Production of gas from coal The sulfur compounds (hydrogen sulphide, carbon disulfide, thiophene, thiols, carbon sulphide) Natural gas processing Hydrogen sulphide, mercaptans Production of acids and alkalis Oxygen compounds of nitrogen and sulfur Production of mineral and Ammonia, sulfur compounds, hydrogen organic compounds fluoride, mercaptans, trimethylamine, etc. Chemical plants (for the Formaldehyde, amines, amides, solvents, production of resins, varnishes, sulfur compounds, acetylene, phenol, etc. plastics, fats, oils, etc.). Pharmaceutical factories, Amines, reduction of a sulfur compound, breweries (processes of furfural, methanol fermentation) Textile and paper mills Urea, decay products, starch, dimethyl sulphide Production of carbon black The steam-gas mixture of waste gases (Н2, (soot) CO, CH4, O2, СО2, N2, H2O)

Table 5 – The grouping of industries by the coefficient of toxicity of emissions into the atmosphere Industries Non-ferrous metallurgy, petrochemical industry, chemical industry Petrochemical industry, microbiological industry Ferrous metallurgy, timber industry, woodworking and pulp and paper industry The power industry, mechanical engineering and metal working, light industry, food industry

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Toxicity coefficient of pollutions 10.1-15 5.1-10 1.6-5.0 1.0-1.5

Estimation of emission toxicity Especially toxic emissions Very toxic emissions Toxic emissions Less toxic emissions

Table 6 – Emissions of chemical elements into the atmosphere in the production of non-ferrous metals, kg/t of metal Element Arsenic Cadmium Copper Mercury Nickel Lead Zinc

Copper-nickel 3.0 0.2 2.5 9.0 3.1 0.845

Manufacturing Zinc-cadmium 0.6 0.5 0.14 0.042 – 2.5 15.7

Lead 0.363 0.005 0.072 0.002 0.085 6.36 0.11

2.2. Impact of Thermal Power Plants (TPP) on the environment The following main types of negative impacts of Thermal Power Plants (TPP) for the environment can be identified [81]: – atmospheric pollution by suspended particles (soot, ash), particulates (PM) and chemical substances (SO2, NOx, CO, CO2, etc.); – «greenhouse effect»; – giant oxygen consumption, which reduces its concentration in atmosphere; – pollution of the lithosphere by solid waste (slag, ash dumps), deposition on the surface of the soil of harmful emissions and their migration into the depths lithosphere; – excessive increase in water consumption, pollution «by sewage waters»; – «acid rains»; – «thermal emissions»; – other negative impacts, including noise and electromagnetic. Thermal power is the source of more environmental 300 types of substances (fig.15), among which the major share is: – Sulfur dioxide; – Carbon oxides; – Nitrogen oxides; – dust of different origin. The main components emitted into the atmosphere during the combustion of various fuels are oxides of nitrogen, sulfur, carbon, soot 55

and ash. During combustion, especially when incomplete combustion, hydrocarbons (methane, ethane), polycyclic hydrocarbons (including benz (a) pyrene (C20H12)), formaldehyde (НСОН), vanadium oxide (V) are marked. The most ecologically imperfect type of fuel is coal, because When it is burned, a larger range of harmful emissions forms, compared with other types of fuel. But coal is the most common fossil fuel on our planet. Experts believe that its reserves will last for 400500 years. When natural gas is burned with significant air pollutants is nitrogen oxides and carbon monoxide (CO). Nitrogen oxides, however, are virtually excluded when using environmentally friendly technologies for its combustion.

Figure 15 – Emissions of TPP in the atmosphere [82-84].

2. 3. Kazakhstan oil and gas processing By the level negative effects on the environment oil and gas industry has the first place among the industries. It pollutes almost all

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spheres of the environment – the atmosphere, hydrosphere, and not only the surface but also groundwater [84]. 2.3.1. Features of oil and gas fields in Kazakhstan 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. 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 were discovered and developed two deposits of high-quality oil – Dossor (since 1911) and Makat (since 1915). 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 12-th place in the world. The country is a leading exporter of oil among the CIS countries (fig.16). 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 factor of expansion of world economic communications, inclusions of the country in globalization processes, realization not only economic interests [15, 85]. The largest oil fields of Kazakhstan are Kashagan, Tengiz, Karachaganak and Kashagan (location – the north of the Caspian Sea) with the geological reserves, estimated to amount to 4.8 billion tons of oil. Tengiz field (location – the 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. 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. It is on Karachaganak that for the first time in the world the technology of reverse injection of a large volume of sulfur-containing gas into the reservoir is applied. This allows maintaining reservoir pressure and producing more liquid hydrocarbons. Really, there is no 57

need to anneal of associated gas. The sulfur recovered from the hydrocarbon feedstock also returns to the formation. And this is also a favorable factor for the environmental situation.

Figure 17 – A map of the main oil and gas fields of Kazakstan

One of the indispensable requirements of the technological process is the exploration of wells. At the same time, ecologically safe, so-called «super green» burners are used. Air compressors supply additional air to the combustion zone, thereby ensuring non-carbon combustion of hydrocarbons and reducing the concentration of the main pollutants. To explore the wells, the innovative multiphase technology «Mega Flow» developed by the British company «Expro» is also used. Its essence lies in the fact that during testing hydrocarbon raw materials are not burned, but are sent back to the oil collection system for further processing. Another significant achievement is the certification of the environmental control system of KPO under the international standard ISO 14001. 2.3.2. The largest oil and gas 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 58

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 [15, 86]. The word қашаған in translation from the Kazakh language means a character trait – «restive, strong-willed, elusive» (more often about an animal). 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 Tor-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 Teңіz, English Tengiz.) is a giant oil and gas fields in the Atyrau region of Kazakhstan, 160 km south-east of 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 jointly 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. 59

Stocks Reserves of oil of 1.1 billion tons. The center of production is 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, Karashyganak Kazakh, English Karachaganak) – 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 on a 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 Buzashinskoy 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. 60

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 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. 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

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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, kazakh Қаламқас-теңіз, англ. Kalamkas «A» offshore is a marine oil field in Kazakhstan. Located 150 km northwest of the Buzachi Peninsula. It was opened on September 3, 2002. Stocks Geological reserves are 156 million tons of oil, recoverable – 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 (kazakh – Қayran, English Kairan) is an offshore oil field in Kazakhstan. It is located to 150 km to the south-east from the city of Atyrau. It was opened on September 10, 2003. 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 of 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 [15, 86, 87]. Project participants The operator of the fields is the oil company CNPCAktyubemunaigaz.

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2.3.3. Kazakhstan refineries The first-born of oil refining in Kazakhstan is the Atyrau refinery. The construction of the plant was 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. Initial capacity of plant on oil refining was 800 thousand 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, which is located in the oldest oil producing region of the country [15, 87]. 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 of fields of the Western region of Kazakhstan with the high content of paraffin. In assortment of products are gasolines, white spirit, diesel fuel, boiler fuel, fuel oil, coke. The Shymkent oil refinery is put into operation in 1985 and the design capacity of the plant on oil refining was 6 million tons per year. In 1994 the enterprise carrying the name of JSC «Shymkentnefteorgsintez» (ShNOS) was privatized, in 2000 was acquired by the Canadian company Hurricane. In 2000 reconstruction of section of hydrotreating of diesel fuel and kerosene was carried out. 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-OmskPavlodar-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 63

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 [86-88]. 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 implementation of the plan was 101.28%. 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 arrangement 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. 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 is realized in two stages: at the first stage it is 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 is 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 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 the primary (separation processes) and secondary processes (oil processing). The plant is one of the most modern in technology in the 64

Republic of Kazakhstan. The plant processes oil in a fuel variant 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 technology, the plant is oriented to 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 distinctive feature of oil products produced in Kazakhstan is low quality and maximum load on the environment. At the refineries available in Kazakhstan, only the line of atmospheric distillation, reforming straight-run gasoline and hydrotreatment of diesel fuel operate. At such scheme of production it isn’t necessary to speak about complex processing, associated fat dry gases are burned in torches or at best move 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. The main production of natural gas is carried out in Aktobe, Atyrau, West Kazakhstan, Kyzylorda and Mangystau regions. Most of all natural gas reserves (about 60%) and condensate (about 80%) contains 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 associated 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 [15, 86]. Along with the refinery, Karachaganak and Mangistau oil and gas processing complexes operate on the territory of the republic.

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2.3.4. Gas processing plants of Kazakhstan In Kazakhstan, there are also the gas processing plants (GPP). To date, the largest gas processing plants (GPP) in Kazakhstan are the Kazakhstan, Tengiz, Karachaganak and Zhanazholsky [89, 90]. 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 m3 of gas per year. It has two technological lines, the first was put into operation in 1991, the second in 1995. At the same time, associated gas from the Tengiz field is characterized by a high content of propane-butane fraction and is characterized by a high content of hydrogen sulphide, the presence of carbon dioxide and associated components that 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. 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. Zhanazhol Gas Processing Plant (ZHGPP) The Zhanazhol oil refinery was originally designed for processing 710 million m3 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 m3 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 66

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 carry out work at the level of international standards. The gas plant at Kumkol is distinguished by a high level of automation, modern software, equipping 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 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 exceptionally 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 effectively combined with the process of obtaining ethane and propane-butane 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 lowtemperature separation of gas into fractions. The annual increase in the production of hydrocarbon raw materials and its further processing raises serious concerns about the environmental situation in the republic. 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 to reach a production level of 100 million tons of oil. 67

Increasing the pace of development of natural oil and gas fields contributes to an increase in the release of pollutants into the atmosphere, the hydrosphere and the lithosphere of the earth. Therefore, monitoring 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 (maximum allowable concentration), the maximum content of 11 MAC. There is a tendency to increase 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 offshore wells. In the Northern Caspian, pollution from oil development to recent years has been insignificant; This was facilitated 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 status of the Northern Caspian, which allow exploration and production of oil (Resolution No. 936 of the Council of Ministers of the Republic of Kazakhstan on 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 Mangistau region, more than 60 deposits have been explored, of which 27 are extracted oil and gas. 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 sea level rise and phenomena in which the coastal enterprises are 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. Currently, more than 20 deposits located in the Atyrau region are already exposed to the Caspian Sea. In Mangistau region began to be subjected to 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 68

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 Sea under the threat of flooding there are more than 40 oil fields, oil and gas fields among which unique – Tengriz, Korolevskoe, Kalamkas, Karazhanbas. In the territory of the Mangystau and Atyrau regions there are about 1,000 earth barns which aren’t provided with any isolation 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 accident it is possible to judge by such figure – oil reserves in the dangerous region are estimated at 5 billion tons. Despite existence of a huge source of raw materials, the petrochemical branch of Kazakhstan doesn’t use fully an opportunity for more full load of capacities of the available enterprises. 2.3.5. Actual problems of Kazakhstan oil and gas processing One of the main problems of oil branch 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%, while 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 69

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 have not produced 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. 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. 2.4. Emissions of oil producing and refineries into the atmosphere Drilling rigs, oil and gas fields are technological objects that release various pollutants into the atmosphere. Contamination of the atmosphere during the testing of productive horizons can be quite intense despite their short-term nature. The amount of flared oil and associated gas depends on the flow rate of fluids and may be hundreds 70

of tons by weight. The combustion process itself can take several weeks. During the drilling of wells, the main sources of air emissions are diesel plants [91]. When drilling wells, the sources of atmospheric pollution are volley emissions during oil and gas occurrences, the combustion of hydrocarbons in flare units during the cleaning of the bottomhole formation zone, and the thermal detoxification of drilling sludge. Every year, in the areas of oil and gas production, one uncontrolled release per 1000 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 comes from pumps and compressors. Usually safety valves dump gases on a torch, but at an overload of a torch of gas it is dumped in the atmosphere. Reverse waters at ablation and evaporation from coolers also pollute the atmosphere. Sources of environmental pollution from petrochemical productions it is conditionally possible to subdivide on envisaged and unorganized (casual). Organized pollutions are caused by investigation, drilling, production, transportation, processes of primary and secondary oil refining. Unorganized pollution is 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 plant (EDP), separation and rectification separation of petroleum associated gas, direct distillation distillation of oil, stabilization of oil emulsions with the use of surfactants. 71

The largest contribution to environmental pollution is made by the organized sources from the main processes of oil and petroleum products processing: vacuum distillation, thermal cracking (pyrolysis, 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 [13, 15, 92]. 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), greenhouse-forming (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 as 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 in the presence of air of fuel oil and boiler fuels on the basis of oil and oil products in the atmosphere it is marked out, along with CO2, CO, SO2, H2S, CnHm, a large amount of nitrogen oxides (NOx), among them there is the greatest number of N2O nitrous oxide, steady in air and capable to collect in an upper atmosphere and then to 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 72

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 [92]. 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 the likelihood of occurrence on the railways of emergency situations leading to oil spillage and, as a result, soil contamination, as well as of land-based and underground water sources. A threat to environmental safety is caused by pipeline transport, the length of which reaches several hundred and thousand 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 25-30 years, the problem of water basin pollution remains very important. One of the main types of pollution is hydrocarbon contamination of the Earth’s water basin. In recent years, serious concern has been 73

caused by the pollution of the oceans by oil as a result of the crash of tankers and oil emissions in boreholes located on the high seas. The big share of pollution is the share of oil transportation (tab.7) as the main oil-extracting areas are located at considerable distance from areas of its consumption and processing. A part of this oil (up to 0.5%) is thrown out 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 [21, 79, 93]. Table 7 – Distribution of the contribution of various sources to the oil pollution of the World Ocean No

Source of pollution

1

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, million tons/year 2.13 1.83 0.3 1.9 0.6 0.6 0.3 0.3 0.2 0.08 0.02 0.06 6.11

Share, % 34.9 30.0 4.9 31.1 9.8 9.8 4.9 4.9 3.3 1.3 0.3 1.0 100

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 soluble in water to varying degrees. 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. 74

2.5. Oil gas as a source of air pollution. Flare 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 [15, 94]. 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 existing sources of pollution. It is necessary to consider high migration activity of gaseous substances which are fixed not only at a pollution source, but also on considerable removal from it. The maximum aura of dispersion (up to 15 km) is characteristic of hydrocarbons, ammonia and carbon oxides; hydrogen sulfide migrates at 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 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 75

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. So, only in Western Siberia, more than 10 billion m3 of gas are flared annually in torches. At the same time, 7 million tons of toxic compounds enter the air basin. 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 rises long ago. But in the conditions of 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, have achieved nearly 100% of utilization of associated gas. Kazakhstan’s petroleum legislation was amended to prohibit the burning of gas in flares and its emissions into the atmosphere from July 1, 2006. Particularly relevant at the same time, the problem of utilization of associated petroleum gas (APG) is seen against the background of Kazakhstan’s ratification of the Kyoto Protocol. Every year in the majority of oil-producing countries of the world when developing oil fields burn and release into the atmosphere 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. According to the World Bank, annually in the world burn 110 billion m3 of associated gas, or 10–13 billion cubic feet a day, and it, for example, is more, than it is required for internal needs of Great 76

Britain. There would be enough volume of the gas burned in only one Africa for production twice of bigger quantity of the electric power, than is annually developed 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 [15, 93, 95]. Air protection in oil industry is carried out, mainly, in the direction of fight against losses of oil due to reduction of its evaporation when collecting, transporting, 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): energy and petrochemical. The energy sector dominates, because energy production has an almost unlimited market. Associated petroleum gas is high-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 product cost, use of APG for generating electricity can be considered economically quite justified. The most effective way of utilization of associated petroleum gas – its processing at gas processing plants with obtaining 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 77

petroleum gas. Depending on the area of the field, per ton of recovered oil can be from 25 to 1,000 m3 of associated gas, which, moreover, is characterized by a high content of sulfur dioxide and methane. Some of the produced associated petroleum gas is about 30% pumped back into the reservoir to maintain reservoir pressure. About 15% is used for own technological needs, electricity generation, including a small part is burned. Commodity gas accounts for about 55% of production. To collect and process associated gas, an expensive special infrastructure is needed, which is why it has been easier for oil producers to burn 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) – 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 [96-98]. 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 instrumental records of the volumes of extraction, use, and burning of resources; – improvement of the order of access of oil companies to production capacities for processing and transportation of APG; – 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. 78

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. 2.6. Pollution of the atmosphere from the extraction of shale gas Slates (or shales) take the isolated place among solid combustible minerals because of high content in them mineral substances [15]. On content of organic mass they are the sapropel formations (but conditions of their origin are differed). Fields of slates are many and they are shared on low-sulphurous, to 2.0 % of sulfur (the Estonian slates) and sulphurous, 2.0-8.0% of sulfur (slates of Central and Lower Volga area). Organic mass of shale is called kerogen, its content is different: shales from light to dark brown in color – 35.0% (55.0%), brown and black shales – up to 35.0%. Ash content of shale by an average is 60.065.0%. Organic shale mass consists of carbon (66.0-77.0%), hydrogen (7.5-9.5%), sulfur (1.8-10%), oxygen (11.0-15.0%) and nitrogen (0.41.0%). Slates (or shales) are also valuable solid combustible minerals because of high content in them mineral substances. People have used shale from ancient times of prehistoric times and as a fuel and as decorative pieces. In the 10th century, a method of extracting oil from «oil shale» has been described by the Arab physician Al-Mardini (Mesue Jr.). In 1596 in the town of Zeefild (the territory of modern Austria) were first processed oil shale (of which began to obtain ichthyol). In the first decade of the twentieth century, mining of oil shale in 1910 reached 3 mln. tons. During the First World War, due to the shortage of liquid fuel, in many European countries

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(Sweden, Switzerland, Austria, Germany) as a raw material for production of synthetic motor fuels examined oil shale. Oil shale of the Baltic basin as technological raw materials have unique properties and allow to obtain at thermal processing such products, which cannot be obtained from oil, coal or oil shale of other deposits. Thanks to the fact that in organic matter of shales, kerogen there is the high content of oxygen (about 10.0%), at thermal processing is formed pitch most of which consists of oxygencontaining compounds, including, water-soluble phenols. Baltic shales – kukersites – are the combustible slates, best in the world, contain 20-60% of kerogen, 20-60% of carbonates and 15-50% of detrital material. In general, the majority of the chemicals produced from slates have unique, specific properties. The growing extraction of shale oil in the USA already allows to speak about the «shale revolution» which divided the world oil market on North American with the low prices of energy carriers and Euroasian where the prices are still high. Experts predict that due to improving of production from oil shale by 2035 the USA will come out on top on oil production, having left behind Saudi Arabia and Russia. Shale gas refers to natural gas that is trapped within shale formations, as different from conventional natural gas resources, such as associated (produced with crude oil), or non-associated (without crude oil) natural gas that is found mostly in sandstone formations [99]. Shales are fine-grained sedimentary rocks that can be rich sources of petroleum and natural gas. Over the past decade, the combination of horizontal drilling and hydraulic fracturing has allowed access to large volumes of shale gas that were previously uneconomical to produce. The production of natural gas from shale formations has invigorated the natural gas industry and the small inland refineries in the United States. Figure 17 shows the EIA data and projections on dry natural gas production in the U.S., indicating the surge in shale gas production, while the conventional associated and non-associated gas production are expected to decline [100]. Dry natural gas refers to natural gas that consists, essentially, of methane without any significant concentration

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of condensable hydrocarbons, such as propane and butane, that are present in natural gas liquids.

Figure 17 – History and projections of dry natural gas production in the U.S. [101-103]

Uzbekistan plans to develop shale Sangruntau in Navoi province and the successful implementation of the project will be the first of Uzbekistan in Central Asia, who masters the production of hydrocarbons from shale. Uzbek oil shale reserves are estimated at 47 billion tons. In Kazakhstan rich with petroleum and gas, according to the candidate of geological and mineralogical sciences, the employee of Institute of geological sciences of RK B. Tsirelson, «the total stocks of raw materials at the explored deposits of oil shale are equal to 5-6 billion tons. The large prospective deposits of oil shale in the Republic of Kazakhstan were opened in the middle of the XX-century. The largest of which – Kenderlykskoe (reserves are estimated at 4-4.5 billion tons), followed by – Baikhozhinski (South Kazakhstan) and the Ural group of fields in the west of the country. On all explored Kazakhstan fields shales come to a surface – at depths of the first tens of meters. During a research of these fields (in the 1950-1980th), it 81

was planned to carry out production by open-pit method. Now the topic of shale was raised in connection with the extraction of shale gas and oil; and to larger depths – up to several hundred meters – then stocks will increase significantly». B. Tsirelson noted that in Baykhozha in the oil shales there is also a large amount of rhenium – rare-earth metal, widely applicable in catalysts and refractory alloys [104]. As there are no precise informations about reserves of oil shales, none of experts undertake to claim how many slate hydrocarbons and in what prospect it would be possible to obtain in Kazakhstan. However at present methods of extraction and taking into account that layers of shales close lie to the land surface, it is possible to say with confidence that extraction of slate hydrocarbons in RK is potentially bound to small expenses and high environmental risks. Shale gas has undoubtedly already made very serious changes in the natural gas market in the US and as a result, in general, in the economy of this country, has an ever increasing impact on the world market. At the same time, outside of the United States, no one has succeeded in repeating this success yet. Nevertheless, many countries persistently consider «slate projects» as some sort of energy wand, a magic key to new large reserves of the energy source. But at the same time it is necessary to clearly understand, at what cost these resources will be extracted. Shale hydrocarbons are harmful not only because modern technologies for their production – hydraulic fracturing of a reservoir (fig.18) – have a multifaceted impact on the environment, they are also dangerous because they can inhibit the development of the renewable energy sector for many years, as in the case of a number of European countries at the present time. Projects for the extraction of shale gas have already begun in the territories of Ukraine and Poland. Taking into account the peculiarities of the technology of fracing (hydrofracturing), which is used in the production of these hydrocarbons, damage can be caused not only to the immediate shale gas production areas, but also to neighboring territories. In gas, which is extracted from shale deposits located around the world, the main component is methane, for which, in fact, the development of deposits is in progress. In addition to methane, shale hydrocarbons such as ethane, propane, and non-combustible gases 82

(CO2 and N2) can be found in shale gas. As a rule, the share of methane in shale gas is more than 80%, but there are deposits (for example, Antrim in the USA), where its share in some areas does not exceed 30%. When drilling, hydraulic fracturing, gas production, gas preparation, etc. part of these gaseous substances is in the ambient air.

Figure 18 – Water cannons used in the production of shale gas, for evaporation of water from the backflow fluid after hydraulic fracturing: another source of air pollution

In general, methane losses during the extraction of shale gas can make from 3.6 to 7.9% of the total production, which is much higher than when extracting natural gas from traditional reservoirs. In this case, in comparison with natural gas production, the stage of preparation for production, and, more precisely, loss of gas, which leaves after hydraulic fracturing of the formation with the backflow fluid, leads to the greatest losses. Most often, the outflow from wells with a return inflow varies from 2 to 8 million cubic feet (0.6 to 2.5 million m3), but in some cases they can reach 42 to 44 million cubic feet (about 13 million m3). On average, the emissions are 7.3 million cubic feet (about 2 million m3). Thus, we are talking about very significant atmospheric air pollution 83

with methane (and its accompanying gases) in the area of development of shale gas deposits. The water of the return influx was the cause of air pollution and other substances. In most cases, these waters, containing both the original chemicals used in hydraulic fracturing of the formation, and substances washed from the enclosing rocks, enter special ground storage facilities. As a result, volatile organic compounds, including benzene, toluene, cumene, formaldehyde, ethylene oxide, etc., can evaporate and enter atmospheric air. In addition, hazardous volatiles can enter atmospheric air and through the wellhead of the downhole equipment [105]. In 2010, the Commission for Environmental Quality (Texas Commission on Environmental Quality-TCEQ) published data on atmospheric air pollution near one of the gas wells located on the territory of the shale deposit Barnett. A total of 35 pollutants were found, and the maximum single benzene concentrations reached 15,000 ppb. Benzene was also detected at 64 points within the drilling site, and its concentration reached 180 ppb. It is clear that the further development of this industry in the world will depend heavily on the fact how successfully the environmental and social problems associated with the technologies for the production of shale hydrocarbons can be solved. In the meantime, «shale projects» imply that for the sake of increasing oil and gas production, irreparable damage to nature can be caused, or conflicts with local communities. Extraction of energy carriers at such a price is unacceptable and inadmissible! 2.7. Environmental impact of oil and gas extraction and drilling 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. Environmental protection includes measures aimed to ensure safety of human settlements, rational use of land and water, prevention of pollution of surface and groundwater, air basin, the preservation of the forest areas, nature reserves, protected zones, etc [106]. Subsoil protection envisages a complex of measures aimed to preventing loss of oil in the ground due to the low quality of sinking 84

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, the upsetting columns and cement behind it. The first characteristic feature of the oil and gas production is a heightened danger of its products. These products have a fire hazard for all living organisms is dangerous by the chemical composition, hydrophobicity, possibly in high-pressure streams of gas to diffuse through the skin into the body by high-pressure jets of abrasiveness. Gas at the mixing with air in certain proportions can form 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 10,000 – 12,000 m. In the process of oil and gas production the extensive and very significant influences on reservoirs (oil, gas, aquifers, etc.) are carried out. Thus the intense selection 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. By reducing reservoir pressure there is a redistribution of load – it is reduced pressure on the pore walls and hence the voltage rising in the rock skeleton formation. These processes reach such a large scale that can lead to earthquakes. Oil and gas production can affect not only the deep-seated in a separate layer, but also on several different by depth layers simultaneously. Balance of the lithosphere is distorted, ie, is disturbed the geological environment. The modern technology of fastening of wells during the drilling process is imperfect and does not provide the reliable formation isolation 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 another regions [15]. 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 gases under high pressure, all the power lines are dangerous, lot of chemicals and materials are toxic. From the wells can be come and from the solution the same toxic gases can be 85

separated such as, for example, hydrogen sulfide. Environmentally hazardous are the torches, in which the unused associated gas is burned. System of collection and transport of oil and gas must be sufficiently hermetic has. The accidents on these objects lead to serious environmental consequences. Fourth feature of oil and gas production is that for its objects it is necessary to withdraw from the agricultural, forestry or other use the relevant plots of land. In other words, the oil and gas industry requires the removal of large areas of land (often in the highly productive lands). Objects of oil and gas occupy a relatively small area in comparison with, for example, a coal mine, occupying a very large area (like itself careers and overburden). However, the number objects of oil and gas is very large. Due to the large dispersion of oil and gas production objects is very high extent of communications. The total area of land allocated under the oil and gas production – the arable lands, forests, hayfields, pastures, reindeer moss, etc. 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 – oil (diesel fuel and oil) [107]. 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 and water and chemicals used to intensification of the processes of oil extraction, drilling and oil treatment, gas and water. By the spatial feature the pollution sources are divided on the point sources (wells, pits), linear (pipes, water lines) and area (oil fields, field). Depending on the duration they are allocated on systematic and temporary sources of pollution. The level of pollution of the environment of the waste production is estimated by multiplicity of excess of maximum allowable (permissible) concentration, MAC(MPC) of entering substances in natural objects. The biggest part of hydrocarbon pollution of the atmosphere, account for 75%, 20% in the surface and ground waters, and 5% – in the soil. Environmental pollutants at the drilling of wells and equipment are numerous chemical reagents which used for the preparation of drilling fluids. 86

During the construction of the drilling 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 adverse effects on soil, surface and groundwater have drilling fluids. During well testing the hydrocarbon pollution is predominated, and at the stage of dismantling of the drilling occurs due to contamination of the territory because of using of the exhaust technical materials and equipment which cannot be recovered. Sources of pollution during drilling can be divided into 2 groups: 1) permanent – filtering and leakage of liquid wastes of drilling from the sludge pits; 2) temporary – a violation of the tightness of the cemented area behind columnes, the casing leading to manifestations and the intersheeted 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. 2.8. 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 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 the generation and accumulation [13, 15, 108]. And this 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 continued – plants for calcined soda. In the middle of the XIX century the chemical industry began to produce artificial mineral fertilizers for agriculture, plastic, synthetic rubber and artificial fibers.

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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, 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). Problems of the chemical industry associated with the environment – not only in the products produced, 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.

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The leading place in the industry is occupied by enterprises using hydrocarbons as raw materials. And this is quite natural. 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 630-700°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: – the production of synthetic ethyl alcohol by direct hydration of ethylene – a source of unsaturated hydrocarbons, ammonia vapors, ethyl alcohol; – production of acetylene – a source of hydrocarbons, hydrocyanic acid, dimethylamine and formic acid, dimethylformamide; – production of synthetic phenol and acetone – 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, the 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.

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2.8.1. Air pollution from the production of elastomers 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. 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 [13, 15, 109, 110]. The complex composition of the released substances is explained by the large range of products produced and, accordingly, the materials and ingredients used for their manufacture, as well as by the variety of processes for obtaining rubber products. At their manufacture are used about 30 kinds of rubbers, more than 100 ingredients, solvents and organic additives. Almost all technological operations of production of rubber products are sources of harmful substances. 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;

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– molding of rubber compound into mold by injection method followed by vulcanization. Preparation of details is carried out by molding through method of injection or calendering of rubber stocks. These operations are followed by heating of a rubber stock at which of it various gases and also dust of talc, a 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 into the atmosphere of various solvents, for example, of GR-1 or GR-2 gasoline, ethyl acetate. At the enterprises of 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, then during vulcanization they are 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 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 are 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. 2.8.2. Impact of the chemical fibers production on the atmosphere At present, the industry produces chemical fibers in the form of monofilament (single fiber of great length), staple fibers (short cuts of 91

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 [3, 15, 111]: 1) preparation of spinning solutions or melts; 2) spinning the fiber; 3) finishing the molded fiber. Preparation of spinning solutions (melts) is begun 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 enter into it various additives 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. On a dry process the spinning solution is pressed through a spinneret into the mine where at evaporation of solvent in hot or cold air the thread is formed. In a wet process, the spinning solution is fed through spinnerets into a precipitation bath filled with a mixture of water and solvents, where the filaments are solidified. 92

The speed of forming filaments from the solution by the «dry» method reaches 300-600 m/min, by the «wet» method – 30-130 m/min. Spinning solution (melt) during the 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 improve 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, which are 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 – thermofixing (usually in a stretched state at 100180°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. 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; – 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 is directed to the

93

thermal and thermocatalytic detoxification facilities, after which, passing through the high pipes, it 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. Degree of extraction of hydrogen sulfide 95-100%. – at the second stage regeneration of carbon disulfide in adsorbers with a stationary layer of adsorbent is carried out. As an adsorbent, which ensure a high degree of purification, active carbons of the brands ART-2 and SKT-3 with a developed volume of micropores are used,. One typical plant provides purification of 450,000-500,000 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. 2.8.3. Impact of manufacture of artificial mineral paints on the state of the atmosphere 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. 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 [15, 79, 112]. The coloring by dipping can reduce the loss of paint and varnish materials to a minimum, however, the pollution of the environment at the same time occurs due to the toxic vapors of solvents released into 94

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 applied to pretreat the surface before painting, washing and hydrotreating air polluted with PVM aerosols and other technological needs. In the process of using the paint equipment, waste water is periodically generated, which requires special cleaning before discharge into the sewage systems. 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. 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 can not be considered rational and economical. Burning in bonfires is a laborious process that requires a lot of fuel consumption and is harmful to the environment, because a large 95

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. 2.9. Characteristic of sources of emissions of petrochemical productions Petrochemical production refers to enterprises with unpleasant smells of emissions, toxic substances and carcinogens, gases. Sources of air pollution [3, 4, 8] 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), in which a high concentration of harmful substances; b) ventilation (emissions of mechanical and natural ventilation with a low content of harmful substances); 96

c) local exhaust ventilation, emissions close to technological. According to the location in the flow of wind, the sources are divided into: 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 ˃ 100ºС; b) heated , 20ºС ˂ Δt ˂100ºС; c) slightly heated, 5˂ Δt ˂ 20ºС; d) isothermal, Δt = 0ºC; e) cooled, Δt ˂0ºС. According to the mode of operation of emission sources in time: a) constants with a uniform one-time ejection; b) changing according to certain laws; d) are 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.). Emissions formed on the open surfaces of treatment facilities, leaks of technical equipment, in places of storage of bulk substances, conditionally organized emissions of tanks. Let’s consider how the scheme of distribution of concentration of harmful substances in the atmosphere from an organized high source of emission (fig. 19) looks. As far as 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 to speak about the presence of three zones of unequal air pollution: the flare emission zone, characterized by relatively low content of harmful substances in the surface layer of the 97

atmosphere; smoke zone – zone of maximum harmful substances content and a zone of gradual reduction of pollution level.

Figure 19 – Distribution of harmful substances in the atmosphere from an organized source of emission of waste gases [113]

At oil refineries and petrochemical enterprises, industrial waste contained in gas emissions, as a rule, is not utilized, but burned in torches and thrown 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 [13, 15, 21]. 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 tab.8.

98

Table 8 – 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

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

The vast majority of substances used in oil refining and petrochemicals have fire and explosive, harmful (toxic), and carcinogenic properties. For the organization of safe operation with hydrocarbonic systems, i.e. for decrease of contact of the service personnel working with these substances and for carrying out a complex of actions for the purpose of prevention of poisonings, the fires, burning and explosions it is necessary to know set of properties of individual substances, the intermediate and final products of processing, dangerous to activity. From the indicators of fire and explosion hazard, in accordance with State Standard, the most applicable: the flammability group, flash point, ignition temperature, temperature limits of autoignition. Most hydrocarbon systems belong to the group of combustible substances, i.e. such as 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 [13, 21, 112]. 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 99

speed that after their inflaming from a source of ignition there is a steady combustion. Combustible liquids with a flash point in a closed crucible not above 61°C belong to flammable liquids (FL). FL are subdivided on: – especially dangerous – having a flash point below -18°C; – constantly dangerous – with flash point from-18 to 23°C; – dangerous at elevated temperature – with 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 called 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. The harmfulness of the substance can be judged by the maximum allowable concentrations (MAC) of them 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, can not cause diseases or abnormalities in the state of health during the whole working period. Working zone is called the space up to 2 m high over the level of a floor or the platform at which places of constant or temporary stay working in process of work are. 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 9 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

100

indispensable element in the design of the relevant refineries and petrochemical enterprises and their subsequent work. 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 against the background of natural, organization of the system of observations of the state of the biosphere under the influence of production.

Acetylene Benzene Butadiene n-Butane Buten-1 n-Hexadecane n-Hexane n-Heptane n-Dodecane Isobutane Isobutylene

Lower Upper

-

2.50

-11

1.43

128

2.02 1.5 1.81 0.47

-26

1.24

-4

1.07

77 -

0.63 1.81 1.78

Hydrocarbons Explosive 81.0 substance Highly flammable 6.7 5 liquid 12.5 Combustible gas 100 8.5 Combustible gas 9.6 Combustible gas Flammable liquid Highly flammable 7.5 liquid Highly flammable 6.7 liquid Flammable liquid 8.4 Combustible gas 9,0 Combustible gas 100

101

Density of gases (vapors) by air

Combustibility, inflammability, explosion hazard

Hazard Class

Concentration volumetric ignition limits,%

MAC mg/m3

Substance

Flash point, °С

Table 9 – Indicators of hazardous properties of individual substances used or obtained in the processing of hydrocarbon systems [13, 112]

0.91 2

2.77

4

1.88 2.07

3.00

4

Isopentane

Highly flammable liquid Isopropylbenzene Highly flammable 36 0.93 4.2 liquid o-Xylene Highly flammable 32 1.00 6.0 liquid m-Xylene Highly flammable 25 1.00 6.0 liquid p-Xylene Highly flammable 25 1.00 6.0 liquid Methane 5.28 15.0 Combustible gas n-Nonan Highly flammable 31 0.84 liquid n-Octane Highly flammable 14 0.94 3.2 liquid n-Pentadecane 115 0.50 Flammable liquid n-pentane Highly flammable -44 1.47 7.8 liquid Propane 2.31 9.5 Combustible gas Propylene 2.30 10.3 Combustible gas Styrene Highly flammable 31 1.06 5.2 liquid n-tetradecane 103 0.54 Flammable liquid Toluene Highly flammable 4 1.25 6.7 liquid n-Tridecan 90 0.58 Flammable liquid 2,2,4Highly flammable -10 1.0 3.2 Trimethylpentane liquid n-Undekan 62 0.69 Flammable liquid Cyclohexane Highly flammable -18 1.31 10.6 liquid Ethane 3.07 15.0 Combustible gas Ethylbenzene Highly flammable 24 1.03 3.9 liquid Ethylene 3.11 32.0 Explosive substance Alcohols, acids, aldehydes, ketones n-Amyl alcohol Highly flammable 49 1.48 liquid Adetaldehyde Highly flammable -38 4.00 55.0 liquid Acetone Highly flammable -18 2.10 13.0 liquid -52

1.36

7.6

102

2.5 50

4

4.14

50

3

3.66

50

3

3.66

50

3

3.66 0.55

2.50 1.56 1.45 5

3

3.58 6.83

50

3

3.20

80

4

2.9 1.05 3.60 0.97

100

4

3.04

5

3

1.52

200

4

2.00

n-Butyl alcohol

Highly flammable 10 liquid n-Hexyl alcohol 63 1.23 5.4 Flammable liquid 10 Isobutyl alcohol Highly flammable 28 1.81 7.3 200 liquid Isopropyl alcohol Highly flammable 13 2.23 12.0 200 liquid Methyl alcohol Highly flammable 8 6.7 34.7 5 liquid Methyethyl ketone Highly flammable -6 1.8 9.5 200 liquid n-Propyl alcohol Highly flammable 23 2.34 13.5 10 liquid Acetic acid Highly flammable 38 3.33 22.0 5 liquid Formaldehyde 7.0 13.6 Combustible gas 0,5 Ethylene glycol 112 4.29 6.35 Flammable liquid Ethanol Highly flammable 13 3.61 19.0 1000 liquid Acetic anhydride Highly flammable 40 1.21 9.9 liquid Compounds containing nitrogen, sulfur, chlorine Ammonia 15.5 28.0 Combustible gas 20 Aniline 73 1.32 8.3 Flammable liquid 0.1 Dimethylformami Highly flammable 58 2.35 10 de liquid 1,2Highly flammable 12 4.60 16.0 10 Dichloroethane liquid Diethylamine Highly flammable -26 1.77 30 liquid Pyridine Highly flammable 20 1.85 12.4 5 liquid Hydrogen sulfide 4.0 46.0 Combustible gas 10 Carbon disulphide Highly flammable -43 1.33 50.0 liquid Chlorobenzene Highly flammable 25 1.40 50 liquid Chloroethane 3.92 Combustible gas Ethers n-Amyl acetate Highly flammable 25 1.08 100 liquid n-Butyl acetate Highly flammable 22 1.43 15.0 200 liquid 38

1.81

12.0

103

3

2.60

3 4

2.56

4

2.10

3

1.11

4

2.51

3

2.10

3

2.0

2

1.04 2.15

4

1.60 3.50

4 2

0.59 3.30

2 2

3.40

4 2

2.70

2

1.19

2

2.60

3

4 4

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

Highly flammable liquid 3.49 Combustible gas Highly flammable 11 1.87 23.4 10 liquid Highly flammable -43 1.90 300 liquid Highly flammable -3 2.28 16.8 200 liquid Highly flammable 18 1.97 22.0 3 liquid Petroleum products and other substances Highly flammable -36 1.05 5.16 100 liquid Highly flammable -36 1.06 5.16 100 liquid Highly flammable -38 1.05 5.16 100 liquid 4.00 75.0 Combustible gas Highly flammable >35 0.61 liquid Highly flammable >40 liquid Highly flammable >40 0.64 300 liquid 150 0.29 Flammable liquid

33

0.70

-

3.66

20

3.10

4

2.60

4

3.04

3

4.00

4

3.60

4

3.60

4

3.60

-

0.66

4

4

0.9

4

-

4

-

2

1.52

Highly flammable liquid

1.60 1.78

Flammable liquid

3

Highly flammable 100 liquid Highly flammable 300 liquid Explosive 80.0 1.0 substance -

To study and solve environmental problems, it is necessary to create information systems that characterize the actual state of the 104

environment. The monitoring of the actual state of the environment is also key in the development, implementation and evaluation of the effectiveness of environmental protection measures. These measures are carried out 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 happening in a surrounding medium and identification of the reasons which caused them; – obtaining the secondary information (statistical processing) based on results of observations or monitoring; – predictions of tendencies of change of an ecological situation at various levels. The issues of environmental protection for the oil refining and petrochemical industry are increasingly urgent. 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 improvement of environmental protection measures. This indicates an increased environmental hazard of these enterprises [109114]. 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 does not allow to define a contribution of each of them to environmental and to estimate influence of sources of emissions of the harmful substances located in the industrial facilities. The solution of these questions requires creation of local systems of monitoring of a 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 the forecasting of environmental situations in large areas. Such systems include, as a rule, several 105

stationary or mobile control stations; the results of measurements are transferred to the information processing center via radio and telephone communication channels. Thus, the solution of the problem of reducing environmental tension in hazardous enterprises is possible through the creation of environmental monitoring systems, and the results obtained with the help of these systems in conjunction with technological measures to increase the environmental friendliness of production will effectively manage 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 illness, 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. According to the report of the World Health Organization in 2014, air pollution in 2012 caused the death of about 7 million people worldwide [109, 112], a rough estimate from the International Energy Agency [113-114]. «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 disease [111, 115]: 40% – ischaemic heart disease; 40% – stroke; 11% – chronic obstructive pulmonary disease (COPD); 6% – lung cancer; 3% – acute lower respiratory infections in children.

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Chapter 3. EMISSIONS OF HARMFUL SUBSTANCES   INTO THE ATMOSPHERE    3.1. General information The degree of atmospheric pollution depends on the amount of emissions of harmful substances and their chemical composition, and also largely on the characteristics of the source of emissions – the height of the source above ground level, the speed, volume and temperature of the gas discharge from the mouth of the pipe, the size of the unorganized source, the location of the source at the site etc. [13, 113]. In accordance with this, the sources of atmospheric pollution differ: on emission power:-powerful, – large, – small; emission height:- low, – medium height, – high, temperature of exhaust gases:- heated, – cold. There are also mobile and stationary, organized and unorganized, point and area sources of pollution. The peculiarity of the enterprise as an object of nature protection measures is the heterogeneity and dispersal of emission sources. Specific sources of atmospheric pollution in enterprises are fugitive emissions, evaporation of hydrocarbons during the storage and transportation of oil and petroleum products, as well as organized emissions emitted from the combustion of various types of fuels and gases in tube furnaces, flare plants, and off-gas regeneration from catalytic cracking units. Despite the fact that flares (see Chapter 2, p.2.5) are a very significant source of emissions, they perform important environmental functions. Flare units are designed to neutralize by combusting combustible (explosive) gases (vapors), the release of which into the atmosphere can lead, above all, to explosion and fire, as well as to harmful effects on humans. Flare installations allow to transfer harmful substances to less dangerous ones, for example, hydrogen sulfide during combustion turns into sulfur dioxide, carbon monoxide into carbon dioxide, etc. The operational characteristics of the flare systems should be characterized by flame stability, the completeness 107

of gas combustion, noise level, reliability of ignition, control efficiency when changing the volume or composition of the combusted gas, and smoke-free operation. Volumes of dumpings of gases on a torch at the enterprises average 0.14% (in some cases to 1%) from the volume of the processed oil. In the USA this index is estimated at 0.19% (0.6%). At the same time 90% of wt., cooperative dumpings on a torch are hydrocarbons, 1.6% of wt. – hydrogen 2.6% of wt. – a hydrogen sulfide, the rest – water vapor and nitrogen. The predominant part of hydrogen sulphide comes with hydrocarbon streams, making up a significant part of them. However the streams containing up to 50% of a hydrogen sulfide are dumped from installations of producing elemental sulfur on a torch. Typical emissions of harmful substances into the atmosphere by the refinery flares are shown in tab.10. It should also be taken into account that the main part of harmful substances is emitted for short periods of time (volley ejection). The amount of emissions into the atmosphere during salvo emissions is 4-5 times higher than the emissions of the entire enterprise. Thus, the protection of the environment depends to a large extent on properly designed and operated flares, which ensure reliable and economical combustion of gas emissions [116]. Table 10 – Emissions of harmful substances into the atmosphere from flare units Gas Hydrocarbons Carbon monoxide Sulfur Oxide Nitric oxide

Emissions for processed oil, kg/t 0.6 0.086 0.165 0.006

Content of this component for the whole refinery,% 11.6 7 17.8 6

To classify the technological processes in terms of their combined harmful impact on the environment, it is suggested to take into account the total toxicity of the emissions. The quantitative expression of the total toxicity of the emissions is the total toxicity index (G3), defined as the sum of the above-mentioned toxicity factors (G1i) of all harmful substances emitted to the atmosphere from sources of their release. Accounting for the index of total toxicity makes it possible to identify the priority of technological processes for their ecological hazard (tab. 108

11). As can be seen from tab. 11, the most environmentally hazardous are the production associated with the rectification of hydrocarbon systems – oils and heavy oil residues, cleaning oils with aromatic substances, elemental sulfur, and facilities for treatment plants. Table 11 – Classification of processes of processing of hydrocarbon systems on ecological danger [13, 79, 113] Priority number 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

Technological process Atmosphere-vacuum distillation of oil Contact cleaning of oils Vacuum distillation of fuel oil Syngas production Mechanical wastewater treatment Selective cleaning of oils with phenol Selective purification of oils by furfural Production of elemental sulfur Regeneration of sour tar Coking residue in cubes Catalytic cracking in a moving layer of a spherical catalyst Thermal cracking of residues Catalytic cracking for refining Combined unit for atmospheric distillation and thermal cracking Catalytic reforming Carbamide dewaxing of diesel fuels Gas desulfurization Gas separation combined Atmospheric distillation of oil Gas separation by rectification Secondary distillation of gasoline Hydrotreatment of oils Obtaining bitumen Flaring facilities Coking slowed down Drain loading overpass Hydrofining of diesel fuels Deasphalting of residual and distillate fuels Pyrolysis of gaseous raw materials Isomerization

109

G3 33,039 8,889 8,884 6,433 6,354 5,034 4,439 4,274 3,717 3,571 3,190 3,140 2,638 2,489 2,058 1,640 1,420 1,347 1,327 1,268 1,249 1,079 894 764 738 671 664 493 363 225

3.2. Characteristics of the main air pollutants 3.2.1. 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, increase resistance to air flow in the airways, disrupt the function of the ciliary epithelium, and increase the secretion of mucus. When background contamination with sulfur dioxide and suspended particles is critical, the concentration in 0.1 mg/m3 should be considered. With the increase of this threshold, 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. [13, 113]. 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; – 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: – the crude gas from installation of utilization of torch gases; – saturated solutions of monoethanol amine (MEA); 110

– hydrogen sulfide – containing gas from technological installations of cleaning and a 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. 3.2.2. Nitrogen oxides Mass emissions of enterprises are nitrogen oxides. 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 characteristic, with large doses of bronchitis and tracheitis. Starting at 0.15 mg/m3, prolonged exposure to an increase in the frequency of violations of respiratory functions and diseases of bronchitis. Nitrogen dioxide is toxic, and in sunlight it is converted to oxide with the release of ozone, which participates in the formation of photochemical smog. Simultaneous emissions of nitrogen 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 [3, 8, 13]. 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 (3): О2 + N2 ↔ 2NO – 180 kJ/mol

(3)

The formation of NO from fuel takes place in two stages: – gasification of fuel oil droplets with the release of nitrogencontaining organic compounds in the form of vapors and gases;

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– reactions of oxidation of vapors and gases with the formation of NO [8, 117]. 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 to 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 (4), (5): H• + C ↔ CH + N•

(4)

N• + O ↔ NO + H•

(5)

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. 3.2.2.1. The impact of N2O on the environment. Sources of N2O in the atmosphere Over the past decades, the influence of «gay gas» (previously considered innocuous) in atmospheric processes leading to ozone depletion and the 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, since there are no conditions for its chemical transformation in them. 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

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the reactive O and •ОН particles formed during photolysis [13, 117, 118]. 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. Those the content of N2O is increased by 0.2-0.3% per year. The main sources of N2O emissions are: – ome chemical industries; – petrochemicals (12%); – 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. 3.2.3. 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 113

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 [13, 117, 119]. 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. 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%). 3.2.4. 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 [21, 109, 114]. The main sources of hydrocarbon emissions into the atmosphere are:

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– 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). The reason for significant emissions of light hydrocarbons from process plants is the lack of proper coupling of the capacities of 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, on which not only the degree of the process’s connection with the environment depends to a large extent, 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 presented in tab.12. Significant air pollution by hydrocarbons in the factories occurs when filling with railroad tank cars and tankers filled with commercial petroleum products on loading racks and berths.

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Table 12 – Gas emission from surfaces of treatment facilities

Source of gas emission Sandboxes Oil Traps The receiving reservoir (oil trap) Receiving well (oil trap) Ponds of additional sludge Quartz Filters

Average concentrations of Gross gas emissions, g/h gases in air flows, mg/m3 hydrogen hydrogen hydrocarbons hydrocarbons sulphide sulphide 314 0.153 10,600 103.3 582 0.302 50,700 26.7 221

0.306

398

0.55

2,204 1,800 990.5

0.306 0.203 0.510

6,470 135,700 28,600

0.9 7.35 14.7

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Chapter 4. PURIFICATION OF THE ATMOSPHERE   FROM GAS EMISSIONS OF INDUSTRY   4.1. 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. Common to 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 is used in the selection of the purification method [1-6, 8, 13, 113]. 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); – reduce to a minimum the amount of waste by the integrated use of raw materials (in the petrochemical and metallurgical enterprises sulfuric acid shops are built using the sulfur dioxide released); – 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 root solution of this issue is to effectively clean up harmful gases and dust before they are released into the atmosphere. Depending on 117

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 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. 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 established for the last MAC in 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 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 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 thermal methods [3, 5, 7, 8]. 4.2. Methods of 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. 118

These methods favorably differ from others (for example, wet cleaning in scrubbers) with a higher degree of purification, the 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 [120]: a) mechanical (filters, electrostatic precipitators); b) physicochemical (adsorption, absorption (physical and chemisorption), membrane, electron beam, oxidative); c) biochemical, microbiological, condensation and compression; d) thermal; e) catalytic (tab. 13). Mechanical methods are designed to capture aerosols (for example, solid dust particles), but they do not provide purification from toxic gases. The most suitable method for cleaning large volumes of air is adsorption. As adsorbents are used silica gels, alumogels, active carbons, porous glasses, zeolites [121]. After desorption, the impurities are not disposed of, but are subjected to thermal or catalytic afterburning [122]. The merit of this method can be attributed to a high degree of purification (95-97%), and to disadvantages – 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 [123, 124]. 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 another part of the apparatus. There are several options for the process of thermal neutralization of gases in furnaces with and without the use of catalysts. In fig. 20 possible options for such a process are shown [125]. According to a scheme A, the waste gases are fed to the afterburner into the furnace. In the prechamber 2 they are heated by the heat 119

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. Table 13 – Methods for cleaning industrial gas emissions from gaseous and vaporous contaminants Cleaning Methods Absorptive Chemisorptive

Adsorptive Thermal

Catalytic

Biochemical

Process type absorption of impurities by a solvent (water) to form a solution chemical interaction of impurities with liquid sorbents (absorbers) with the formation of volatile or slightly soluble chemical compounds Adsorption of impurities on the surface of a solid Oxidation of pollution by air oxygen at high temperatures with the formation of non-toxic (less toxic) compounds Catalytic chemical reaction of contamination with other impurities or added substances with the formation of non-toxic (less toxic) compounds Transformation of impurities under the influence of enzymes produced by microorganisms

Devices (apparatus) towers with nozzles, scrubbers, bubble-foam machines towers with nozzles, scrubbers, spray devices Adsorbers Combustion chambers

Catalytic and thermocatalytic reactors

Biofilters, bioscrubbers

According to scheme B, in contrast to scheme A, 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, similar schemes B and C, but in the zone of the furnace 3 for the oxidation catalyst 5 is used.

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Figure 20 – Schemes of possible options for 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 – the furnace; 4 – heat exchanger; 5 – catalyst.

4.2.1. Gas emissions purification by the catalytic method Among the known methods of utilization and neutralization of harmful industrial emissions, the most effective 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 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 [126, 127]: 121

ωk = kωCa1Cb2

(6)

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

(7)

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. 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. Analysis of the literature shows that the oxidation of toluene, styrene, xylenes, α-methylstyrene and butadiene on the known industrial catalyst AP-56 (0.56% Pt%) reaches 94-97%. Along with platinum, palladium catalysts of the P-series (0.5%) are also used, whose activity in the deep oxidation reactions of organic emissions is close to that of platinum ones [128, 129]. At the polymer materials plant of Ukrplastic and EPKTB Selstroyplastic, the P-4 catalyst provided 97-100% purification of the gas emissions of decorative paper laminate production from phenol (up to 300 mg/m3), formaldehyde (up to 20 mg/m3), ethanol (up to 50 122

mg/m3) at a space velocity of 20,000 h-1 and an inlet temperature of 350°C. The catalyst was operated for 5 years without changing the efficiency. Also on the catalyst P-4 was achieved 95-100% purification of the gas emissions of the Syzran Plastics Plant (printing shop for polymer film) from methyl ethyl ketone (up to 2,350 mg/m3) and cyclohexanone (up to 20-400 mg/m3) in the presence of SO2 (up to 50 mg/m3), CO (up to 2%) and moisture (5%) at a volumetric rate of 12, 000 h-1 and a temperature of 350°C. To neutralize the gases of the drying chambers of the painting lines of the Minsk Motorcycle Plant from xylene, solvent and toluene the platinum-palladium catalyst was used. The degree of purification at 300-340°C and the space velocity up to 30,000 h-1 reached 90-100%. The catalyst worked for more than 2 years without reducing its activity. This catalyst also achieved 85-99% purification of waste gases produced by enameling wires on the «Moscable» software from solvents at 450°C [129]. Comparative tests of catalysts: platinum AP-56, NIIOGAZ-3D and 10D; palladium NIIOGAZ-10DA, P-4 in the oxidation reactions of a mixture of ammonia, ethanol, benzene, acrolein, formaldehyde, acetic aldehyde, methanol, ethanol, phenol, carbon monoxide, sulfur oxide, etc., formed in the foundry industry with a cold-hardening mixture allowed to establish that complete neutralization is achieved on NIIOGAZ-3D catalysts at 450°C, AP-56 at 300°C (volumetric rate of 10,000 h-1). These catalysts are recommended for further tests on real gas emissions of the foundry. In the production of phthalic anhydride, the degree of gas purification on the catalysts of the platinum (AP) and palladium (P) series was about 100% at volumetric rates of 10,000-20,000 h-1 and 200-280°C. Thus, catalysts based on noble metals have become widespread in the purification of harmful emissions of industry. Catalysts based on platinum metals have high activity at low temperatures, durability, heat resistance and the ability to work stably at high space 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 due, 123

first of all, 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. Catalysts developed at the Dzerzhinsk branch of NIIOGAZ, at the rate of neutralization of 30,000-60,000 volumes of neutralized gas per volume of catalyst mass per hour and at a temperature of 350-420°C, are active for neutralization of impurities of ethylene, propylene, butane, propane, acetaldehyde, alcohols (methyl, ethyl, propyl, allyl, etc.), acetone, ethyl acetone, benzene, toluene, xylene, carbon monoxide, etc. 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 neutralization. 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 [130134]. 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. On 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. A large spread for the destruction of toxic substances in the flue gases was obtained by flare incinerators (see Chapter 2, p.2.5). To flare installations, high demands are placed on ensuring safe and reliable operation in the conditions of fire and explosion hazard of chemical plants.

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The fulfillment of these requirements is achieved by observing the following conditions [135-137]: – 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 altitude of the flare burner installation, low torches about 4-25 m in height and high torches, which in some cases reach altitudes of 100 m and more. To ensure a stable and productive purification process, a catalyst of the brand SHPK-05 manufactured by the Redkinskii Plant [138] was chosen, which is produced on the basis of a special active aluminum oxide ball bearing and is a spherical shaped pellet with a diameter of 4 mm with a layer of the active component, palladium. The content of precious metal (Pd) is 0.5%. The bulk density of the catalyst is 0.8 kg/dm3. The productivity, or «activity», of the catalyst is associated not only with the presence of palladium in its composition, but also with a high specific surface area of 120-140 m2/g. 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 [139-154]. Researchers of Kazakhstan more than 50 years have been creating and investigating (fig.21) efficient stable catalysts of cleaning of gas emissions of the industry and conversion of organic compounds [16, 17, 60, 128, 155-183]. Thus, palladium containing catalysts P-4 and P-5 were developed. The P-4 catalyst was tested in a pilot installation of «Plasticsfuntitura», Lviv, Ukraine, in the reaction of deep oxidation of styrene (225 mg/m3). At a temperature of 400°C and a space velocity of 15,000-20,000 h-1, the degree of oxidation of styrene on the catalyst reaches 94-96%. The developed palladium catalysts P-4 and P-5 are not inferior in activity to the platinum catalyst AP-56. Catalyst P-4 was 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 [156-160]. The P-5 catalyst was introduced at the «Kuibyshev Cable» plant to neutralize tricresol and phenol in the 125

production of enamel wires, where the oxidation degree was 97-99% at 400-400°C with volumetric rates of 10,000-40,000 h-1.

Figure 21 – Installations for researches of catalytic gas purification

The synthesized polyoxide Ni-Cu-Cr catalyst supported on 2 % Ce/θ-Al2O3 provides 98.8% toluene conversion to CO2 at space 126

velocity of 5×103 h-1 and temperature 450-500ºC and content of toluene in the feed mixture equal to 320 mg/m3 [157]. On the pilot and experimental basis of JSC «D.V. Sokolsky IFCE» (fig.22) the full-size block catalysts on metal carriers with honeycomb channel structure were prepared and tested [171-175 ]. 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 the smooth and corrugated foil in the metal block of cylindrical shape, followed by the application of active agents (based on metal compounds of Groups 78). The synthesized catalysts (fig.23) 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 cylindrical in shape and easy to place at the source of toxic emissions. Three types of catalysts (on the basis of 0.2% Pd, 0.1% Pt and 0.1% Pt) promoted with manganese oxides and nickel were tested in the reaction of oxidation of CO and CH4 before and after prolonged exploitation. After that the prepared full-size catalysts were forwarded to assembly, where cylinders were made. There were pins for the catalysts in the cylinders (fig.24). The diameter of the block filter for the furnace PTB-10/64 was 410 mm, height – 400 mm. For PT-furnace 16/150 the diameter of the catalytic filter – 500 mm, height 400 mm, and the dimensions of the catalyst for 3.5-PT oven were 900 mm by 400 mm. The catalytic filters were installed directly on exhaust gas pipes of oil heating furnaces after before-the-catalyst samples were taken (fig.25) In order to reduce heat transfer the catalysts were wrapped with insulating mineral wool with reflective foil. On the oil-field «S.Balgimbaevo» (Kazakhstan) the concentration of toxic gases before the catalyst was 1,280 ppm as per carbon monoxide (CO), 49 ppm as per nitrogen oxide (NO), and 51 ppm as per total nitrogen oxides (NOx); after the catalyst there was 5 ppm of CO, 39 ppm for NO, and 41 ppm for NOx. Thus efficiency of the neutralization of toxic emissions was as follows CO-99.6%, NO20.4%, NOx-19.6%.

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a

b

Figure 22 – The equipment on the pilot and experimental basis 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 23 – Ready-to-operate fullsize block catalysts on metal carriers for neutralization of wastes of industry

Figure 24 – The block catalytic converter for neutralization of toxic emissions of oil heating ovens PT 16/150 and PTB/10/64

On the oilfield «Southwestern Kamyshitovoye» (Kazakhstan) efficiency of neutralization of toxic emissions in PT-3,5 furnace with the catalytic filter was as follows CO-66.8%, NO-20.6%, NOx-20% and SO2-100%. Reduction of toxic emissions in the furnaces PT16/150 after the catalyst was 100% for CO, 7.7% for NO, 7.7% for NOx, and 57.1% for SO2. During the pilot tests it was revealed that the catalytic filters worked effectively and reduce the content of toxic

128

gases from 7.7% as per nitrogen oxides and up to 100% as per carbon monoxide. In [171, 172, 174] the purpose was preparation of catalysts with various active phase on metal block carriers and test of their effectiveness on natural gases of the stationary diesel generator at various loadings. The active phase was prepared on the basis of the platinum group metals, oxides of nickel, manganese. For testing the efficiency of the catalysts the stand on the basis of diesel generator of brand 5GF-LDE with power of 5 kVA was used (fig.26, 27). The fullsize catalyst samples had a diameter of 30.0 mm, a height of 90.0 mm. The catalyst was loaded into the gas-abstersive offshoot of the diesel generator.

Figure 25 – Technological scheme of the installation and operation of the catalyst in the of oil heating furnace: 1 – the furnace of heating of oil, 2 – a chimney, 3 – catalytic neutralizer, 4,5 – stream of off-gases (CO, CHx, NOx) to the catalyst, 6,7 – a stream of gases after the catalyst

129

The experiments were carried out at all operating modes of the diesel engine generator (in the idle mode and for loadings 1.0-4.0 kVA). An analysis of exhaust gases before and after the catalyst showed that the lowest percentage of oxidation of harmful components is characteristic for engine power conditions – up to 5.0 kVA, rpm. – up to 490.0, when gases have a low temperature (up to 280°C). With increasing load on the engine, the degree of deep oxidation of harmful components increased and remained in the range of CO values from 40.0 to 90.0%, hydrocarbons from 35.0 to 100% for nitrogen oxides from 10.0 to 40.0%. Thus, synthesized catalysts at 200°C or higher provide high performance in testing on the bench.

Figure 26 – The catalytic unit (the stand) on the basis of diesel generator

The catalyst on base 0.1% of Pt at bench experiments worked on the diesel generator more than 100 h. without decrease of efficiency. At all engine operating conditions the most effective sample was catalyst containing 5% nickel and manganese oxides, activated by 0.1% of Pt. The catalytic samples on the basis of Ni and Mn promoted

130

by Pd (0.1%, 0.25%) and Pt (0.1%), provide high degree of transformation CO to CO2, СхНy into CO2 and H2O, NO to N2.

Figure 27 – A schema of a stand on the basis of the stationary diesel generator: 1 – the diesel generator; 2 – the exhaust pipe; 3 – the catalytic reactor; 4 – the catalyst sample; 5 – the vapour sensor; 6, 7 – sampling valves before and after the catalyst; 8 – a gas analyzer.

A feature of the works [176, 180, 182, 183] is the use of cheap natural raw materials of Kazakhstan, clays, in the synthesis of catalysts. Authors used the samples prepared on the base of natural zeolites of Chankanai deposit (Kerbulak district of Almaty region) a Taizhuzgen deposit (Tarbagatai district of East-Kazakhstan region). The obtained data and the analysis of literature sources [184, 185] allow to authors to conclude that the structure of natural zeolite can be improved by using various modifiers in the corporation [186-190] and by means of a mode of setting thermal preparation samples. It has been shown that compositions of molding materials have been developed for the manufacture of a supporting structure for catalysts for purification of gases in the form of granules and premolds to satisfy the requirements for plastic properties and mechanical resistance. It was found that the optimum value of mechanical resistance is 27.6 MPa, when the ratio of zeolite/bentonite in molding materials is 60/40, and the heating temperature is 1,000°C per hour in air. Further on, the methods for cleaning up specific components of gas emissions will be described.

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4.3. Reduction of gas emissions of various components 4.3.1. Sulfur dioxide and hydrogen sulfide. Reduction of SO2 and H2S emissions The main methods of protecting the air basin for 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. 4.3.1.1. Removal of sulfur from fuel before its combustion 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 [191]. 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 are operated in a number of the countries of the region of the Caribbean Sea 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 particular, in the form of FeS2 iron sulphide, also called iron pyrites.

132

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. 4.3.1.2. Purification gases from sulfur compounds of combustion products of fuels (desulfurization flue gases) In recent years, a large number of various methods of cleaning flue gases from sulfur, based on various chemical and physical principles was developed [192]: 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 industrial gases from sulfur dioxide is the use of solutions and suspensions of compounds of alkali, alkaline earth metals, aluminum, organic substances (sulfitebisulfite 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 133

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. A large number of works are devoted to the study of gas purification from sulfur dioxide with the use of solutions and suspension of bases and salts of alkaline-earth elements [13, 21, 191194]. The main place in the world practice of desulfurization desulfurization is occupied by 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. The cleaning is carried out in a column apparatus with a height of 36 m and a diameter of 14 m. 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 134

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. A citrate method for desulfurization of flue gases containing up to 30% of mass, 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%. A significant amount of work is devoted to the purification of gases using organic sorbents. To purify gases from hydrogen sulphide, an absorbent solvent containing an organic base, dimethylformamide and cobalt phthalocyanine are proposed. The method for removing sulfur dioxide from gas streams by contacting with oxoalkanes is patented. The resulting adduct with sulfur dioxide is hydrolyzed to form sulfuric acid and the original absorbent, which is recycled. The process of desulfurization of flue gases with a high content of carbon dioxide using solvents such as methanol, N-methylpyrrolidone or dimethyl ether of polyethylene glycol is proposed. At the first stage of purification, the absorption of hydrogen sulphide and a portion of carbon dioxide takes place. In the second stage, the gas is further purified from CO2 and H2S. The solvent is regenerated by increasing the temperature of the impure solution. From the gas stream enriched with hydrogen sulfide, after Claus regeneration elemental sulfur is obtained [13, 195]. 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 alkaline-earth elements. To remove harmful impurities from gases with simultaneous 135

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 [13, 196]. 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%. 4.3.2. Purification of gases 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 [196, 197], structures based on carbon materials [198, 199], and metal-organic framework structures [200, 201]. 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 [202]. For processing after gas combustion, it has also been proposed to use CO2 capture by materials based on dry alkali metals [203-208]. 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 [209, 210]. A solid material that captures CO2 from the simulated flue gas using a bifunctional material containing the adsorbent and catalyst is described in the works [209, 210]. A bifunctional material consists of nanodispersed calcium oxide (CaO) and ruthenium (Ru) dispersed on 136

a high surface area carrier (Al2O3). It is a two-stage process involving the adsorption of CO2 in vapors containing wetted flue gas followed by H2 methanation at 593 K and 0.1 MPa. The methanization reaction takes place through a process in which adsorbed CO2 is poured into reconstructed sections of Ru, where the renewable stored H2 catalytically converts it to CH4. The processes of CO2 adsorption and methanization are exothermic processes. This nanodispersed state (~ 3 nm) and promotes chemisorption, rather than the formation of carbonates [211]. When deposited on γ-Al2O3, dispersed CaO adsorbs CO2 only as a reversibly bound structure, which differs from the monodentate carbonates [212215], formed on volumetric CaO at the same temperature state (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) 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 [216-218]. 4.3.3. Purification of gases from nitrogen oxides 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 the production of nitric acid, 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 137

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 [219-221]. 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 slightly inferior to coal, but it is more durable and not oxidized by oxygen. In the D.I. Mendeleev Technical University was developed a carbamide method that allows to purify flue gases from nitrogen oxides by 95% and almost completely remove sulfur oxides from them. The process does not require preliminary preparation of gases, as a result of purification, non-toxic products – N2, CO2, H2O and (NH4)2 are formed. The pH of the absorption solution fluctuates between 5 and 9, so there is no corrosion of the equipment. The efficiency of the method is practically independent of fluctuations in the inlet concentrations of nitrogen and sulfur oxides. To test the method in industrial conditions at Zmievskaya Hydroelectric Power Station (Ukraine), a pilot plant was constructed. 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. 4.3.3.1. Catalytic reduction 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. 138

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. Process temperature ranges from 400ºC to 800ºC [222, 223]. 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 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 is used at a temperature of 120°C and a pressure of 0.3 MPa: 6 NO + 4 NH3 (excess) = 5 N2 + 6H2O

(8)

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

(9)

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

(10)

Purified of nitrogen oxides gas is released into the atmosphere. Since all chemical processes used in the purification scheme are carried out 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 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 11-13), has become widespread worldwide for the purification of industrial gases and gases from power plants. 3N2O + 2NH3 = 4N2 + 3H2O

(11)

6NO + 4NH3 = 5N2 + 6H2O

(12)

6NO2 + 8NH3 = 7N2 + 12H2O

(13)

139

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 (14) 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 [224]. The catalyst of Shell V2O5/TiO2 is known in the form of granules or honeycomb blocks operating at a space velocity of 40,000 m3/m3 (cat.)H. The promoting effect is produced by tungsten oxide WO3, silicate additives are used as ligaments. The catalyst is not resistant to sulphation. At low concentrations of sulfur oxides in flue gases, the life of the catalyst is 16 years. However, this catalyst is active in a narrow temperature range of 300-400°C, at higher temperatures nitrous oxide is formed. The disadvantage of this catalyst is also its instability with an increase in temperature of 600-800°C [225]. Authors of [226] considered the mechanism of operation of the industrial V2O5 – WO3/TiO2 catalysts for reduction NOx by ammonia. They offered the following mechanism of reaction (15)-(17). NO2 is exposed to disproportionation and heterolytic chemosorption and then forms the adsorbed nitrite and nitrate: 2NO2+H2O ↔ HONO+HNO3

(15)

NO acts as a reducing agent, converts nitrates and nitrites: HNO3+NO ↔ HONO+NO2 140

(16)

NH3 reacts with nitrites, forming non-toxic nitrogen and H2O in the decomposition of intermediate unstable ammonium nitrite: HONO+NH3 → N2 +2H2O

(17)

If NO is deficient, ammonia can also react with nitrites to form ammonium nitrate, which, under certain conditions, is embedded in the catalyst. A similar mechanism is proposed based on studies of infrared spectroscopy of the reaction on the catalyst BA-NA-zeolite Y. In [227, 228] the temperature effect on interaction of nitrogen cotaining gases with Ru-black by method of the temperature programmed desorption was investigated. Authors wrote that Ru is the most selective catalyst in the reduction of nitrogen oxides. The chemisorption of NO on Ru is accompanied by its dissociation into nitrogen and oxygen. The authors studied this problem by thermal desorption. They found that the adsorption temperature significantly affects the amount of desorbed NO and its decomposition mechanism. Figure 28 shows the differential thermal desorption spectra. As can be seen from fig. 28, N2O is released in a narrow temperature range (55255°C with Tmax = 100ºC and Edes N2O = 13.9 kcal/mol (first order desorption). The amount of N2O decreased with increasing pretreatment temperature and completely disappeared at 150°C. After NO interaction with Ru black at 25-350ºC, gases transformation is revealed in two temperature ranges: 50-250ºC for NO, N2O, N2 and 250-500ºC for NO and N2. Desorption of oxygen was not revealed. X-ray phase analysis data shows, that it interacts with Ru and RuO2 forms. The energies of desorption of NO from Rublack, Edes= 66.5 kJ/mol and Edes= 82.8 kJ/mol in temperature ranges I and II, respectively, are close to the chemisorption of NO treats on «reduced» (62.8 kJ/mol) and «oxidized» (79.5 kJ/mol) Ru, defined by the method of interacting bonds. Authors suggested that NO desorbs in range I, NO(I) is a linear structure bonded to «reduced» Ru by a nitrogen atom. Reduction of emissions of nitrogen oxides in the atmosphere by controlling the combustion process 141

Along with the installation of gas cleaning equipment at the end of the technological cycle of fuel combustion, a number of regime and technological measures that significantly reduce the amount of nitrogen oxides formed during combustion are very effective.

Figure 28 – The influence of the interaction temperature of NO and Ru-black on NO desorption and formation of N2O and N2

These activities 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; – the use of burners, allowing 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 by a radical reduction of the amount of nitrogen oxides formed.

142

Chapter 5. EXHAUST GASES OF VEHICLES    5.1. The main components of the exhaust gases of transport. Impact of exhaust gases 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 into 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. Researches of scientists show, that from year to year the maintenance of carbonic gas in atmosphere increases. This leads to the so-called «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 [3, 13, 21, 117, 173-176, 229-234]. 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 15,000-20,000 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 is emitted annually (million tons): about 80 – sulfur 143

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, which requires significant changes in the technology of production of motor fuels. Road transport emissions relate to emissions from mobile sources and are determined by emissions of vehicle pollutants during their transport operations. Exhaust gases (off-gases) are the waste substances which are in the engine, they are products of oxidation and incomplete combustion of hydrocarbonic fuel [235-237]. 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 the smogs which are the frequent reason of poisoning in selfcontained 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 [173-176]: – 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. 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 the nature caused by some products of combustion of fuels are given in tab. 14. The quality of fuels has significant effect on formation of harmful emissions. Undesirable is the presence in the fuels of large quantities of olefinic and aromatic hydrocarbons, sulfur, ash components. 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; 144

– from 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. Table 14 – Combustion products of fuels and their environmentally harmful effect [245-249] Name Carbon oxide

Ecologically harmful consequences Toxic effect on humans and animals

Technical solutions

Optimization of the combustion process of fuels. Application of additives Sulfur oxides Irritation of respiratory system; Development of fuels with acid rain formation; destruction of reduced sulfur content catalytic converters Nitrogen oxide Irritation of respiratory system; Catalytic reduction of nitrogen the formation of acid rains and oxides in combustion products smog; participation in the destruction of the ozone screen Hydrocarbons Carcinogenic action; participation Reduction of saturated vapor in the creation of the greenhouse pressure of fuels; optimization effect, the formation of ozone and of the combustion process, the smog use of additives Ozone Toxic effect on flora and fauna; Reducing the emission of participation in smog education ozone-forming substances: hydrocarbons and nitrogen oxides Aldehydes Irritant effect on organisms; Improving the combustion participate in the formation of process smog Compounds of Toxic effect on flora and fauna; Development of fuels lead and other violation of the balance of containing no metal metals microelements in water and soil; compounds poisoning of afterburning catalysts Particulate Carcinogenic action, participation Decrease in ash content of matter and soot in the formation of smog and acid fuels, reduction of sulfur and rain aromatic hydrocarbons content

145

Growth of environmental pollution from the motor transport and growth of number of vehicle fleet were the reason of toughening of requirements to qualitative ecological characteristics of products of oil-processing industry [237-240]. Prior to 1987, various national fuel specifications were in force [240-244]. 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 tab.15 and tab.16 [13, 21, 117]. Table 15 – Number of pollutants emitted by passenger (g/person-km) and freight (g/ton-km) transport No Name 1 a Railways b High-speed railways c Motor transport d Air transport 2 a Railways b Motor transport c Water transport

SOx 0.27 0.16 0.14 0.09 -

NOx Particulate matter СО Passenger transport: 0.15 0.09 0.009 0.09 0.05 0.005 3.35 0.07 0.66 0.03 Freight transport: 0.40 0.08 1.96 0.04 0.58 0.04

СН

СО2

0.005 0.003

60.9 35.8

5.01 1.42

0.77 0.23

160.3 234.1

0.06 2.2 0.2

0.02 0.97 0.08

-

Table 16 – 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

146

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 80-90% fall on cars, 5-8% in railways, 1-2% in air transport and 1% in 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; – greater degree of localization and concentration of pollutants than from other sources; – the location in areas with a high population density and the 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); – 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 the small number of devices by means of which removal of harmful substances to the environment is carried out. It allows to hold more effective measures for reduction and neutralization of emissions, than from numerous mobile sources [250252]. 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 other sources. Sources of toxic 147

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 tab.17. The bulk of pollutants (with the exception of sulfur oxides) is emitted when internal combustion engines (ICE) operate. In 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; – 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 tab. 18. Table 17 – 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 1.4 2

148

Diesel engines 9 33 6 20 6 16

Thermal stations 0,05 14 21 0.4 0.08 1.3

Table 18 – 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 [3, 13, 21]. It is connected with the content in the fulfilled gases of the engine of the following substances: – 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 at combustion of sulfurcontaining fuel already 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. Irritation of a mucosa of eyes, cough concentration causes 0.05 mg/l. The most admissible concentration of sulfur dioxide in air of the production enterprises 0.02 mg/l are considered. One of the most common components of gas emissions of motor vehicles are nitrogen oxides. Their share, for example, in large cities of developed countries, accounts for 48-63% of total emissions from all available sources. 149

Nitrogen oxides are a particular hazard: – 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 mass 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%. The increase in carbon monoxide emissions is observed with a decrease in the excess air ratio, low speed and idling of the engines, 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 particularly dangerous. The ability to displace oxygen from compounds with hemoglobin is explained by the increased affinity of hemoglobin to carbon monoxide (200-300 times greater than to oxygen), resulting in the formation of carboxyhemoglobin. Carbon monoxide affects the 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 there are more than 200: > 32% are saturated hydrocarbons; ~ 27% – unsaturated hydrocarbons; – up to 4% – aromatic hydrocarbons; ~ 2% – aldehydes [253-255]. 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 the 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: 150

– 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. The special danger to the person and the environment is represented by the lead and its compounds which are contained in gas emissions of cars. Compounds of lead, mainly tetraethyl lead (thermal power plant), add to gasolines for the purpose of increase in octane numbers. Lead and its compounds, getting to an organism, cause the most serious illness (intellectual backwardness, change of behavioural functions of an 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 number of these compounds fall into 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% [8, 13, 21]. It is also established that when the lead is completely removed, the emissions of hydrocarbons and nitrogen oxides are reduced by 30%. Therefore, the removal of lead from commercial gasoline allowed 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), is used a concentration index, a dimensionless quantity that takes into account the amount of harmful emissions and the degree of its toxicity. 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.

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5.1.1. Nitrogen oxides emissions According to the degree of toxicological effects on the human body, nitrogen oxides are classified as hazard class 3 (moderately hazardous substances) [229]. 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 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 [230, 231]. 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 [232]. In addition, nitrogen oxides contribute to an increase in the ozone concentration in the surface layer [233], and also participate in the formation of photochemical smog [234]. 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 rain of 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 the 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 a 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 152

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, blood pressure decreases. After inhalation for 6-8 min. of air containing approximately 6 mg/l of nitrogen oxide and 3 mg/l for 12 min., death occurs. Poisoning with nitrogen dioxide is characterized by pulmonary edema followed by bronchopneumonia. A lethal concentration of 0.1 mg/l 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 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 (17)-(18): [235]). According to this mechanism, O2 dissociates into atoms at high temperatures and interacts with N2 in accordance with the following reversible chain reactions [236]: O + N2 ↔ NO + N

(18)

N + O2 ↔ NO + O

(19)

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) [237]. CH radicals existing in the flame front can react with atmospheric nitrogen to form cyanic acid, which in turn reacts according to the scheme: 153

CH + N2 ↔ HCN + N

(20)

N + OH ↔ H + NO

(21)

Unlike «thermal», «fast» NOx can form at lower temperatures (~ 700°C) [234]. 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.29 [117, 238.]. According to this scheme, the 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 [239]. Annually in the atmospheric air about 180 million tons of nitrogen oxides are emitted [240]. 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 [232]. Unlike naturally occurring nitrogen oxides, anthropogenic emissions (60 million tons of NOx per year [240]) 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; 154

– explosives; – fertilizers; – agriculture, etc.

Figure 29 – Mechanism of NO production from fuel nitrogen [238].

Among the anthropogenic sources, motor transport contributes most to the pollution of atmospheric air with nitrogen oxides [241]. 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 [242]. 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) [243]. 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.19) [244]. Thus, the average car with an annual mileage of 16.7 thousand km [245] 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[13, 117]. 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 155

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. 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 19 – Compositions of exhaust gasoline and diesel engines (in the absence of a catalyst) [240, 244] Components of exhaust gases Temperature, °С Volumetric speed, h-1 λ (air / fuel) CO2 H2O O2 N2 H2 Sum CO HC NOx Sum SO2 Solid particles

Gas engine kg/l of fuel % wt. Conditions Tamb – 1,100 30,000 – 100,000 1 (14.7) 2.019 17.0 0.990 8.3 0.13 1.1 8.568 7.2 42·10-3 3.5·10-2 98.4 0.167 1.4 1.5·10-2 0.13 1.3·10-2 0.11 1.64 2.4·10-4 2.0·10-3 -

Diesel engine kg/l of fuel % wt. Tamb -650 (Tamb -420) 30,000 – 100,000 1.8 (26) 2.612 7.1 0.917 2.6 5.554 15.0 27.838 75.2 7.0·10-4 2.0·10-3 99.9 1.1·10-2 3.0·10-2 2.5·10-3 7.0·10-3 1.1·10-2 3.0·10-2 0.074 3.7·10-3 1·10-2 2.1·10-3 6.0·10-3

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

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The emission standards for nitrogen oxides applied to road transport were first introduced in the European Union in 1992 (Euro1) (see Chapter 6). 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 [246]. 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 [247, 248]. 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. 5.2. Air pollution from road transport in the cities around the world 92% of the population on Earth lives in places with polluted air – these are the data of the World Health Organization. It is associated with about 3 million deaths per year. 90% of them occur in low- and middle-income countries. 2 out of 3 cases occur in South-East Asia and the West-Pacific region. 94% of the diseases that lead to death are non-contagious: mainly cardiovascular and lung diseases. Contaminated air can also become a breeding ground for acute respiratory infections. Vulnerable more often than others are children, women and the elderly. The cause of polluted air is the inefficient use of transport, incineration of waste, coal-fired power plants and industrial activities. Worldwide Implementation: Emission Regulation: US EPA, California Air Resources Board (CARB), European Standards (Euro), Japanese Standards (JMOE). Emerging Emission Regulation: Chinese Standard, India Bharat Stage Standard, Brazil CONAMA, Korean KMOE. Standards must be developed for specific regions of the world. The likelihood of developing cardiovascular diseases, cancer and stroke increases in areas with high levels of air pollution. Studies show 157

that the infant mortality rate is higher in countries with high air pollution. According to the World Health Organization (WHO), air pollution now poses a much greater health threat than Ebola or HIV, and 80% of all urban areas have air pollution levels above standard standards [256]. The cleanest air in the world is in New Zealand, Solomon Islands, Kiribati and Brunei Darussalam. The Middle Eastern countries, rich in oil, dominate the top ten places in the most polluted of PM places around the world (by level of PM): Saudi Arabia – 108, Qatar – 103, Egypt – 93, Bangladesh – 84, Kuwait – 75, Cameroon -65, Mauritania – 65, Nepal – 64, United Arab Emirates – 64, India – 62 [257]. Table 20 – Top-countries by PM Countries Libya Bahrain Pakistan Niger Uganda China Myanmar Iraq Butane Oman

Level of particulate matter 61 60 60 59 57 54 51 50 48 48

The United Kingdom took 159-th place on the list with the level of solid particles 12. The United States received the 173rd place with an impressive low level of particulate matter. The countries like China (fig.30) that are notorious for lack of clean air in their cities pollute the air, which amounts to 1/2 from the sum of Saudi Arabia. China scored 54 levels compared to the terrifying number of particles in Saudi Arabia, equal to 108. Saudi Arabia is the best offender in the most polluted city bets.

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Figure 30 – Smog in Beijing, the capital of China

5.2.1. Ecological problems of Kazakhstan. Air pollution from road transport in the cities of Kazakhstan One of the most complicated environmental problems in Kazakhstan is the radiation contamination of the territory of Kazakhstan. Nuclear tests conducted since 1949 at the Semipalatinsk test site resulted in the infection of a huge territory in Central and Eastern Kazakhstan. There were several polygons in the republic where nuclear tests were conducted, in the immediate vicinity of the borders of Kazakhstan there is also the Chinese testing range Lob-Nor. The radiation background in the RK also increases as a result of the formation of ozone holes during the launch of spacecraft from the Baikonur cosmodrome [258]. A huge problem for the RK is radioactive waste. So, Ulba plant accumulated about 100,000 tons of waste contaminated with uranium, thorium, and waste storage facility located in the city of UstKamenogorsk. In Kazakhstan there are only 3 repositories for nuclear waste and all of them are located in the aquifer. Precisely the seriousness of the problem of radiation pollution led to the fact that one of the first laws of sovereign Kazakhstan was the Decree of 30.08.1991 on the prohibition of testing at the Semipalatinsk test site. 159

Depletion of water resources has become one of the most serious environmental problems in Kazakhstan. Expanding the scale of freshwater consumption, primarily for irrigated agriculture, has led to salinization and depletion of natural water sources. Especially disastrous was the shallowing of the Aral Sea due to the irrational use of the waters of the Amudarya and the Syr Darya. The sea level fell by 13 meters, the exposed seabed turned into a salt desert. Annual dust storms spread salt to the vast territories of Eurasia. Reduction of the sea has led to a change in the direction of winds and climatic characteristics of the region. A similar situation has developed on Lake Balkhash, the level of which declined by 2.8 -3 meters in 10-15 years. At the same time, the rise of the Caspian Sea continues, caused by an ill-conceived decision to drain the Gulf of Kara-Bogazgol. Large sections of coastal areas, pasture areas and promising oil-bearing areas have already been flooded. Zyryanovskiy lead and Ridder (Leninogorsk) metallurgical works caused contamination of the Irtysh. An alarming ecological situation has developed in the valley of the Ili and Ural rivers. The state priorities in the «Strategy-2030» of the Republic of Kazakhstan include: environmental safety, rational use of natural resources, environmental well-being of citizens and some problems of social ecology. The response to the first environmental crises and catastrophes was expressed in the «Environmental Law» of 1997 [259]. The territory of Kazakhstan due to its geographical position and climatic conditions is subject to many natural disasters – environmental risks affecting the economy of the republic. Serious is the problem of air pollution, especially in large industrial centers of Kazakhstan. According to the World Meteorological Organization, the destruction of the ozone layer over the past 25 years has been 10%. Over Kazakhstan, where observations of the total ozone content have been carried out since 1973 at five stations, the thickness of the ozone layer has been reduced by 5-7 %. On some days, lower values of ozone in the atmosphere may be observed, which causes an increase in the doses of ultraviolet radiation, which are extremely dangerous for humans. Kazakhstan ratified the Vienna Convention for the Protection of the Ozone Layer, and the Montreal Protocol to the Vienna 160

Convention. According to the «Strategy 2030», the Government of the Republic of Kazakhstan, the Concept for Environmental Safety takes possible measures to protect the ozone layer and limit consumption of ozone-depleting substances. An integrated approach is needed to develop a state system of measures to adapt to changing natural and climatic conditions, based on the achievements of advanced science and technology, on the experience of other states aimed at reducing the vulnerability of natural and human systems to existing and expected climate changes. The main pollution of the atmosphere is associated with emissions from non-ferrous metallurgy, heat power, ferrous metallurgy, oil and gas complex and transport. The reality of threats from air pollution affects the deterioration of public health and environmental degradation. The problem of atmospheric air pollution is inherent mainly in large cities and industrial agglomerations, where about half of the country's population lives. Pollution of the air basin is also associated with the development of old hydrocarbons and the development of new ones, which leads to an increase in air pollution by hydrogen sulphide and mercaptans. The flaring of associated gas is accompanied by the release of a large amount of greenhouse gases, sulfur and nitrogen oxides into the atmosphere, an increased thermal background forms around the deposit [13, 15]. As for air of Kazakhstan cities [258-264], high levels of pollution are characterized by the cities of Stepnogorsk, Ust-Kamenogorsk, Kostanay, Pavlodar, Temirtau, Karaganda and the village of Glubokoe. An increased level of pollution was recorded in the cities of Saran, Taraz, Shymkent, Uralsk, Petropavlovsk, Zhanatas, Shu, Aktobe, Balkhash, Karatau, Semey, Zhezkazgan, Atyrau, Akay, Karabalyk, Kordai, Yanvartsevo and Beineu. According to the data, the lowest level of atmospheric air pollution is in the cities of Aksu, Ridder, Kyzylorda, Zhanaozen, Ekibastuz, Kentau, Rudny, Kulsary, Kokshetau, Aktau, Sarybulak, Toretam, Berezovka, Borovoe and Shchuchinsk-Borovskaya resorts. Astana, Almaty, Taldykorgan and Turkistan are among the cities that have a very high (fourth) degree of air pollution, tengrinews.kz reports with reference to the design bureau Igraphickz.

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According to the research, in the air of Taldykorgan there are suspended particles of PM-10 and hydrogen sulphide. Suspended PM10 particles are formed by burning fossil and other fuels. Hydrogen sulphide arises from the decomposition of organic substances and is found in sewage waters of municipal and domestic, metallurgical, chemical, pulp and paper, tanneries in large concentrations. Suspended particles of PM-10 are also fixed in the air of Turkestan [13, 15]. «The basis is the greatest repeatability of exceeding MPC (MAC). Meteorological stations or meteorological stations «Kazhydromet» with varying frequency (for example, every 20 min. or 3 times a day – depending on the substance) measure the content of harmful substances in the atmosphere. Often these substances exceed the MPC (MAC) almost always or, for example, only in the daytime. All data are collected and the repeatability of the month is calculated, for example, 99.7 percent shows that every day any harmful substance in ozduhe exceeded the norm», – stated in the explanation to the statistical data. The cities of Temirtau, Balkhash and Karaganda occupy 4-6 places among the CIS cities and 1-3 in Kazakhstan in terms of gross emissions of harmful substances into the atmosphere. According to environmentalists, the most unfavorable ecological situation has developed in the cities of Temirtau and Balkhash, where the enterprises of JSC «ArcelorMittal Temirtau» and the corporation «Kazakhmys» are located. Stationary pollution sources located in the Karaganda region emit more than 800,000 tons of waste per year, which is more than 30% of all emissions in the republic. The development of industry in the region was carried out without taking into account the environmental consequences, and as a consequence, the quality of the environment in Central Kazakhstan is characterized as unfavorable. According to the data, in Astana, the main pollutants are sulfur dioxide, which is released into the atmosphere as a result of the operation of thermal power plants when burning brown coal and fuel oil, as well as sulfur-containing petroleum products and in the production of metals from sulfur-containing ores.

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Residents of Astana complain of smog in the city (fig.31). Mayor of Astana Aset Isekeshev told how the city authorities will solve the smog problem. There are three sources of air pollution in Astana now: CHP, private heating and transport. According to environmentalists, about 50% is air pollution from transport (gasoline quality, high level of motorization). Mayor of Astana plans to install additional equipment at CHP, it will take about two years to install. On furnace heating, of course, the main issue is the gasification of Astana, now there is a lot of work on this project. And the establishment of new requirements for the quality of coal and the quality of the fuel burned in the private sector. On transport, here is a difficult task, first, it’s need to tighten control over the quality of gasoline and diesel fuel. Secondly, Mayor of Astana added «We are now planning to switch at least the communal equipment to gas at the first stage». As Isekeshev noted, Nazarbayev University in Astana switched to gas [261, 262].

Figure 31 – Smog in Astana, the capital of Kazakhstan

5.2.1.1. Ecological problems of Almaty The southern capital of the Republic of Kazakhstan, Almaty, is a very unique city by its physico-geographical and natural climatic characteristics. Almaty is located in the north of the mountain spurs of the Tien Shan mountain system, at the northern foot of the Zailiysky Alatau, on the cones of the Ul’ken (Big) interfluve between Almaty 163

and Kishi (Malaya) of Almaty. In Almaty, the natural zones of the severe north and hot south are interbreeding [258-264]. The complex terrain and climatic features create unfavorable conditions for the dispersion of impurities from low emission sources, as a result of which harmful substances accumulate in high concentrations, which then take part in the formation of smog phenomena. The most polluted environment in Almaty, according to the Center for Monitoring the Environment, is the city’s atmospheric air (fig.32). The main source of atmospheric air pollution in Almaty is motor transport. As a result, in the atmospheric air of Almaty, an increased content of formaldehyde, nitrogen dioxide, phenols, carbon monoxide was noted. The most disadvantaged areas of the city are areas of CHP1, highway along the avenue Raiymbek District canning factory. In Almaty the amount of harmful emissions into the atmosphere is more than 200,000 tons per year, of which about 75% is motor transport. Almaty’s atmosphere is heavily polluted, and the concentration of impurities in a number of components far exceeds the MAC. The main harmful impurities in the air are dust, soot, carbon monoxide, nitrogen oxides, etc. In the Almaty air there is nitrogen dioxide, which is formed when fuel is burnt at very high temperatures and excess oxygen. The main sources are automobile exhaust fumes, CHP emissions, solid waste incineration and gas combustion. Comparison of data on atmospheric pollution in Almaty with concentrations of harmful impurities in other cities shows that Almaty is one of the most polluted cities in the CIS. The main reason for such high and persistent pollution of the atmosphere are climatic conditions of Almaty city that are unfavorable from the point of view of atmospheric pollution. These include, first of all, weak wind currents (average annual wind speed of 1.7 m/sec.) and a powerful temperature inversion that contribute to the accumulation of harmful components in the city’s atmosphere. Due to the disadvantageous location of the city in the alignment of the Almaty gorge, cold air draining from the mountains at night, stagnates in the streets and squares, causes stable temperature inversions in the winter for several days. In the cold period of the year, the concentration of dust, soot and carbon monoxide in the morning and evening hours is higher than in the daytime, which is due to the presence of surface 164

inversions during these periods. The concentration of nitrogen dioxide is higher in daytime (12 hours) and evening (18 hours) hours and is associated with the most intensive traffic. The concentration of sulfur dioxide increases by the end of the day. In the warm season, the concentration of all impurities is less than in the cold season, with a decrease towards the end of the day [13, 15].

Figure 32 – Smog in Almaty [263]

Astronauts of the International Space Station (ISS) have captured a smoke smog on the Nikon D4 camera over the city of Almaty (fig.33). The gray cloud is very clearly visible from outer space, Zakon.kz reports with reference to the site of Еarthobservatory.nasa.gov. Noteworthy is the fact that the photo was taken in winter – February 28, 2015. In addition, the picture also captures the Kapchagai reservoir and one of the largest lakes in the world – Issyk-Kul.

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Figure 33 – Smog over Almaty is visible even from outer space [264]

So, being one of the most beautiful cities of our country, Almaty remains one of the most disfunctional in the ecological plan.

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Chapter 6. NORMS OF EMISSIONS OF HARMFUL  SUBSTANCES BY CARS IN THE WORLD    The problem of environmental friendliness of cars arose in the middle of the twentieth century, when cars became a mass product. European countries, being in a relatively small area, before the others began to apply various environmental standards. They existed in separate countries and included various requirements for the content of harmful substances in the exhaust gases of cars [265]. Legislative norms for the emission of harmful gases are constantly being improved, norms are becoming more stringent. The test program varies among the three main legislators: in the US, in Japan and in Europe. In 1988, the UN Economic Commission for Europe introduced a single regulation (the so-called Euro-0) with requirements to reduce emissions of carbon monoxide, nitric oxide and other substances in cars. Once in several years, the requirements became tougher, other states also began to introduce similar standards. In tab.21 different levels of pollution are shown. Table 21 – Classification of Pollution by Level

Production level Low (L) Moderate (M) High (H) Critical (C)

Annual Mean Concentration Range (μg/m3) Industrial, residential, rural Ecological Sensitive Area and other areas SO2 NO2 PM10 SO2 NO2 PM10 0-25 0-20 0-30 0-10 0-15 0-30 26-50 21-40 31-60 11-20 16-30 31-60 51-75 41-60 61-90 21-30 31-45 61-90 ˃75 ˃60 ˃90 ˃30 ˃45 ˃90

6.1. Emission standards in the USA The mechanisms generating photochemical smog were elucidated in the United States at the beginning of the 1950s, at which point the need to control automobile exhaust was recognized. The American Clean Air Act (also called the Muskie Act) was passed in 1970, and even stricter emissions control legislation has followed. 167

Since 1990, the regulations of various countries and their subregions have become increasingly strict, ecpesially such as in California. The Federal Standard for Car Emissions in the US for passenger cars is divided into three categories: low-emission vehicles (LEV), ultra-low-emission vehicles (ULEV-hybrids) and vehicles with superlow emissions (SULEV-electric vehicles). There are separate requirements for each of the classes. In the US, there are two regulatory centers: the EPA Environment Agency and the California Air Resources Board. In California the norms are the toughest. In general, all manufacturers and dealers selling vehicles in the US adhere to the requirements for emissions into the atmosphere of the agency EPA (LEV II), tab.22: Table 22 – Requirements for emissions into the atmosphere of the agency EPA (LEV II)

Category

LEV ULEV SULEV

Mileage (miles) 50,000 120,000 50,000 120,000 120,000

NonMethane Organic Gases (NMOG), g/mi 0.075 0.090 0.040 0.055 0.010

Nitrogen oxides (NOx), g/mi 0.05 0.07 0.05 0.07 0.02

Carbon Formaldeh Particulate monoxide yde matter (CO), (HCHO), (PM) g/mi g/mi 3.4 4.2 1.7 2.1 1.0

0.015 0.018 0.008 0.011 0.004

– 0.01 – 0.01 0.01

In tab. 23 shows the standards adopted in California in different years [266, 267]. More recently, more economical engines have been developed that produce less CO2. So, regulations in US for diesel engines (fig.34): Clean Air Act of 1963 – Ist government look into stationary emissions. Clean Air Act 1970 – Regulation of 6 criteria pollutants such as CO, SOx, NOx, Hydrocarbons, ozone and Particulate Matter (PM). 168

Clean Air Act of 1990-Acid rain control plus 189 secondary pollutants. Since then, there are numerous periodic reductions. Ultra-Low Sulfur Diesel (ULSD) mandatory 2007. Table 23 – Standards for the emission of harmful gases, adopted in California, g/mile Years 1992 1994 2003 2004 2003 2005 2005

СН 0.25 0.25 0.25 0.125 0.075 0.040 0.010

СО 3.40 3.40 3.40 3.40 3.40 1.70 1.0

NOx 0.40 0.40 0.40 0.40 0.40 0.40 0.20

Soot 0.08 0.08 0.08 0.04

Figure 34 – Regulations in US on diesel engines [268]

Other countries have adopted either European or Japanese norms. For example, Korea and Brazil adopted American standards, and China and India are European.

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6.2. Euro-fuel standards on fuels In tab.24 are shown the European standards. Euro-0 – 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 [269]. 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) - solid particles (particulate matter) – not regulated - smoke – not regulated. As for the emission by diesel engines, there is no information. Table 24 – Standards for emissions of harmful gases in Europe, g/km Years 1993 1997 2000 2005

СН 0.2 0.1

СО 2.72 2.2 2.3 1.0

NOx 0.15 0.08

СН+NOx 0.97 0.5 -

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 [270]. Euro-2 was introduced into the European Union as a replacement for Euro-1 in 1995. In turn, it was replaced by the Euro-3 standard in 1999 [271]. Euro-3 was introduced in the European Union in 1999 and replaced by the Euro-4 standard in 2005 [272]. Euro-4 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 [273]. 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 170

catalytic converters or filters of technological purification (magnetic, ultrasonic, etc.), which allows 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. Euro-5 – the standard is mandatory for all new trucks sold in the EU since October 2008. For passenger cars – from September 1, 2009 [274]. 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 [275]. Table 25 shows the environmental standards for passenger cars (in units of g/km) [265, 269-276]. Table 25 – Environmental standards for passenger cars according to Euro standards (in units of g/ km) Volatile Carbon Hydrocarb Nitrogen Ecological organic monoxide ons oxide standard compound (CO) СxНy (NOx) s 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

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

2.72 (3.16) 2.2 2.3 1.0 1.000 1.000

For diesel engine 0.50 0.25 0.180 0.080 For gasoline engine 0.20 0.15 0.10 0.08 0.100 0.068 0.060 0.100 0.068 0.060 -

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HC+NOx

Suspended particles, particulate matter (PM)

0.97 (1.13) 0.14 (0.18) 0.7 0.08 0.56 0.05 0.30 0.025 0.230 0.005 0.170 0.005 0.97 (1.13) 0.5 -

0.005 0.005

6.3. Regulations in Japan In Japan, emissions regulations regarding carbon monoxide in car exhaust were first passed in 1966, and regulations similar to the Muskie Act were put in place in 1973 [277]. It’s clear that at the time, the Japan regulations were said to be the most severe in the world. Statistics from the Ministry of the Environment of Japan show that in 2011 transport accounted for 19.6% of CO2 emissions, and this NOx (g/km) continues to grow annually [278]. Figure 35 shows the tendencies in regulations of NOx norms (sum of the NO+NO2 amounts) during the period of years 1995-2020.

Figure 35 – Comparison of NOx norms in US, Europe and Japan during 1995-2020 y.y.

6.4. Emission standards in India In order to properly monitor the concentrations of pollutants, the Central Council for Pollution Control (KOPB) in 1984-1985 launched a national air quality monitoring network, which was subsequently renamed the National Air Monitoring Program (N.A.M.P.). The Central Pollution Control Board has identified and revised the National Ambient Air Quality Standards on April 11, 1994 which was notified in Gazette of India, Extra-ordinary Part-II Section 3, sub section (ii), dated May 20, 1994 [279-285]. The vehicle emissions standards were established for the first time in the 1990s when the government, in accordance with the Supreme Court order, introduced European standards in 1999. Later, this was 172

replaced by the Bharat Stage Emission standards. In 1990, the union government adopted a revised law on motor vehicles, according to which emission standards are regulated by the federal government. India has set limits on carbon monoxide emissions (idle) for cars, motorcycles and three-wheeled vehicles with a gasoline engine; emissions of diesel smoke are limited to 75 Hartridge units at full load. Central pollution control initiated the National Atmospheric Air Quality Monitoring Program (NAAQM) in 1984 with 7 stations in Agra and Anpara. Subsequently, the program was renamed the National Air Quality Monitoring Program (NAMP). Gradually, the air quality monitoring network was strengthened by increasing the number of monitoring stations from 28 to 365 during 1985-2009. The quality of air in the different cities was compared to the corresponding NAAQS (tab.26). Exceedence Factor is the ratio of annual mean concentration of a pollutant with that of a respective standard. The four air quality categories are: - Critical pollution (C): if EF is > 1.5; - High pollution (H): if EF is between 1.0 –