Energy from Toxic Organic Waste for Heat and Power Generation 9780081025284, 9780081025291, 1511511591, 0081025289

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Energy from Toxic Organic Waste for Heat and Power Generation

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Energy from Toxic Organic Waste for Heat and Power Generation

Edited by

Debabrata Barik

An imprint of Elsevier

Woodhead Publishing is an imprint of Elsevier The Officers’ Mess Business Centre, Royston Road, Duxford, CB22 4QH, United Kingdom 50 Hampshire Street, 5th Floor, Cambridge, MA 02139, United States The Boulevard, Langford Lane, Kidlington, OX5 1GB, United Kingdom © 2019 Elsevier Ltd. All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or any information storage and retrieval system, without permission in writing from the publisher. Details on how to seek permission, further information about the Publisher’s permissions policies and our arrangements with organizations such as the Copyright Clearance Center and the Copyright Licensing Agency, can be found at our website: www.elsevier.com/permissions. This book and the individual contributions contained in it are protected under copyright by the Publisher (other than as may be noted herein). Notices Knowledge and best practice in this field are constantly changing. As new research and experience broaden our understanding, changes in research methods, professional practices, or medical treatment may become necessary. Practitioners and researchers must always rely on their own experience and knowledge in evaluating and using any information, methods, compounds, or experiments described herein. In using such information or methods they should be mindful of their own safety and the safety of others, including parties for whom they have a professional responsibility. To the fullest extent of the law, neither the Publisher nor the authors, contributors, or editors, assume any liability for any injury and/or damage to persons or property as a matter of products liability, negligence or otherwise, or from any use or operation of any methods, products, instructions, or ideas contained in the material herein. Library of Congress Cataloging-in-Publication Data A catalog record for this book is available from the Library of Congress British Library Cataloguing-in-Publication Data A catalogue record for this book is available from the British Library ISBN: 978-0-08-102528-4 ISBN: 978-0-08-102529-1 For information on all Woodhead publications visit our website at https://www.elsevier.com/books-and-journals

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CONTENTS Contributors ix

1. Introduction to Energy From Toxic Organic Waste For Heat and Power Generation

2. Toxic Waste From Municipality

1

Debabrata Barik

7

Aravind Sam, Debabrata Barik

2.1 Introduction 7 2.2 Methods of Energy Recovery From Wastes 9 2.3 Conclusions 15 References 16

3. Energy Extraction From Toxic Waste Originating From Food Processing Industries

17

Debabrata Barik

3.1 Introduction 17 3.2 Properties of Food Processing Waste 18 3.3 Food Waste and Its Associated Problem 19 3.4 Food Waste Within the Food-Energy-Water Nexus: A Proposed Conceptual Model 20 3.5 Reducing Food Waste: A Problem of Human Behavior 21 3.6 Conclusions 39 References 39 Further Reading 42

4. Toxic Waste From Textile Industries

43

N.M. Sivaram, P.M. Gopal, Debabrata Barik

4.1 Introduction 43 4.2 Global Textile Scenario 44 4.3 Pollution in Textile Industry 44 4.4 Toxic or Hazardous Wastes 46 4.5 Contaminated Textile Effluents With Chemicals 46 4.6 Chlorinated Solvents 46 4.7 Hydrocarbon Solvents—Aliphatic Hydrocarbons 47 v

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4.8 Hydrocarbon Solvents—Aromatic Hydrocarbons 47 4.9 Oxygenated Solvents (Alcohols/Glycols/Ethers/Esters/ Ketones/Aldehydes) 47 4.10 Grease and Oil Impregnated Wastes 48 4.11 Used Oils 49 4.12 Dyestuffs and Pigments Containing Dangerous Substances 49 4.13 Heat and Energy Generation From Textile Industry Waste 50 4.14 Microbial Fuel Cells 50 4.15 Conclusion 52 References 52

5. Toxic Waste From Leather Industries

55

N.M. Sivaram, Debabrata Barik

5.1 Leather Industry 55 5.2 Leather Production Processes 56 5.3 Pollution From Leather Industry 56 5.4 Toxic Chemicals Used in Leather Industry 59 5.5 Heat and Energy Generation From Leather Processing Waste 61 References 64

6. Toxic Waste From Biodiesel Production Industries and Its Utilization

69

G. Vignesh, Debabrata Barik

6.1 Introduction 69 6.2 Biodiesel Production 70 6.3 Waste From Biodiesel Production 76 6.4 Utilization of Waste From Biodiesel Production 79 6.5 Conclusions 79 References 81 Further Reading 82

7. Paper Industry Wastes and Energy Generation From Wastes

83

P.M. Gopal, N.M. Sivaram, Debabrata Barik

7.1 Introduction 83 7.2 Paper Making 84 7.3 Wastes 86 7.4 Production of Energy Products From Paper Mill Wastes 89 7.5 Conclusions 93 References 95



Contents

8. Health Hazards of Medical Waste and its Disposal

vii

99

K.K. Padmanabhan, Debabrata Barik

8.1 Introduction 99 8.2 Fundamental Principles of a Waste Management Program 99 8.3 Categories of Health-Care Waste 101 8.4 Minimization, Recycling 106 8.5 Minimum Approach to Overall Management of Health-Care Waste 107 8.6 The Way Forward 113 8.7 Parameters to Be Monitored by the Waste-Management Officer 114 8.8 Financial Aspects of Health-Care Waste Management 116 8.9 National Plans for Health-Care Waste Management 116 Further Reading 117

9. Hazardous Waste and Its Treatment Process

119

R. Prakash, M. Gowtham

9.1 Introduction 119 9.2 Hazardous Wastes Management in India 121 9.3 Hazardous Waste: Identification and Classification 123 9.4 Hazardous Waste Treatment 129 References 137

10. Cracking of Toxic Waste

139

R. Prakash, R. Siddharth, N. Gunasekar

10.1 Introduction 139 10.2 Toxic Waste Worldwide—Status 139 10.3 Toxic Waste: Identification and Classification 140 10.4 Cracking of Toxic Waste 143 10.5 Other Methods 146 10.6 Conclusions 148 References 148

11. Power Generation From Renewable Energy Sources Derived From Biodiesel and Low Energy Content Producer Gas for Rural Electrification

151

N.R. Banapurmath, V.S. Yaliwal, S.Y. Adaganti, Sushrut S. Halewadimath

11.1 Introduction 151 11.2 Present Work 159 11.3 Development of Reactor Shell for LDPE 160 11.4 Down Draft Gasifier for Production of Producer Gas 164

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11.5 Properties of HOME, Fuel Oil, and Producer Gas 165 11.6 Experimental Setup 167 11.7 Results and Discussions 175 11.8 Performance, Combustion, and Emission Characteristics of Dual Fuel Engine 178 11.9 Conclusions 191 References 192

12. Economic Factors for Toxic Waste Management

195

Debabrata Barik

12.1 Introduction 195 12.2 Waste and Its Management for Economic Growth 196 12.3 Economic Assessment 198 12.4 Urbanization Environmental Degradation and Economic Growth 198 12.5 Energy From the Waste 200 12.6 Conclusions 202 References 202

13. Comprehensive Remark on Waste to Energy and Waste Disposal Problems

205

Debabrata Barik

Index 211

CONTRIBUTORS S.Y. Adaganti

Department of Mechanical Engineering, SDM College of Engineering and Technology, Dharwad, India

N.R. Banapurmath

Department of Mechanical Engineering, BVB College of Engineering and Technology, Hubli, India

Debabrata Barik

Department of Mechanical Engineering, Karpagam Academy of Higher Education, Coimbatore, India

P.M. Gopal

Department of Mechanical Engineering, Karpagam Academy of Higher Education, Coimbatore, India

M. Gowtham

School of Mechanical Engineering,Vellore Institute of Technology (VIT),Vellore, India

N. Gunasekar

Department of Mechanical Engineering, Sri Ramakrishna Engineering College, Coimbatore, India

Sushrut S. Halewadimath

Department of Mechanical Engineering, KLE Institute of Technology, Hubballi, India

K.K. Padmanabhan

Department of Automobile Engineering, Karpagam Academy of Higher Education, Coimbatore, India

R. Prakash

School of Mechanical Engineering,Vellore Institute of Technology (VIT),Vellore, India

Aravind Sam

Department of Mechanical Engineering, Karpagam Academy of Higher Education, Coimbatore, India

R. Siddharth

School of Mechanical Engineering,Vellore Institute of Technology (VIT),Vellore, India

N.M. Sivaram

Department of Mechanical Engineering, National Institute of Technology Puducherry, Karaikal, U.T. of Puducherry, India

G. Vignesh

Department of Mechanical Engineering, Karpagam Academy of Higher Education, Coimbatore, India

V.S. Yaliwal

Department of Mechanical Engineering, SDM College of Engineering and Technology, Dharwad, India

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CHAPTER 1

Introduction to Energy From Toxic Organic Waste For Heat and Power Generation Debabrata Barik

Department of Mechanical Engineering, Karpagam Academy of Higher Education, Coimbatore, India

There are few things that are certain in life; one is death, second is change, and the other is a waste. No one can stop these things taking place in life. But, with improved management, it can be possible to reduce the waste. Everyone has a right to clean air, water, food, and environment. This right can be fulfilled by maintaining a clear and healthy ecosystem. Now, as a first question, what is waste? Anything which is not needed by the owner, producer, or processor is waste. Generally, waste is defined as at the end of the product life cycle and is disposed of in landfills. Most businesses define waste as “anything that does not create value.” In a common man’s eye, anything that is unwanted or not useful is garbage or waste. However, scientifically speaking, there is no waste as such in the world. Almost all the components of waste have some potential, if it is converted or treated in a scientific manner. Hence, we can define waste as organic or inorganic waste materials produced out of household, commercial activities, and industries that have lost their value in the eyes of the first owner, but which may be of great value to somebody else. Generation of waste is unavoidable in every habitation howsoever big or small. Since the dawn of civilization, humanity has gradually deviated from nature and today there has been a drastic change in the lifestyle of human society. A direct reflection of this change is noticed in the nature and the quantity of garbage that a civilized community generates. The waste can be disposed properly or can be reused to make money through proper management for the economic and environmental growth of individual and society. Many countries which are fast competing with global economies in their drive for faster economic development have so far failed to effectively manage the huge quantity of waste generated. There are 195 countries in the world today and approximately 2.5 million cities including small towns. Energy from Toxic Organic Waste for Heat and Power Generation https://doi.org/10.1016/B978-0-08-102528-4.00001-8

© 2019 Elsevier Ltd. All rights reserved.

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Energy from Toxic Organic Waste for Heat and Power Generation

About 80% of the world’s total population live in urban areas as per 2018 survey. Urbanization combined with the overall growth of the world’s population could add another 2.5 billion people to urban populations by 2050. The quantum of waste generated in the towns and cities are increasing day by day on account of its increasing population and increased GDP. Population explosion, coupled with improved lifestyle of people, results in increased generation of toxic wastes in urban as well as rural areas. However, due to ever increasing urbanization, fast adoption of use and throw concept, and equally fast communication between urban and rural areas, the gap between the two is diminishing. The waste from rural areas is more of a biodegradable nature and the same from urban areas contains more nonbiodegradable components like plastics and packaging. The objectionable attitude toward waste and its management is, however, common in both the sectors. Universally, “making garbage out of sight” is the commonly followed practice. Generally, in urban areas, local bodies, popularly known as the municipal corporations/councils, are responsible for the management of activities of wastes concern to public health. However, in the present era, with increasing public awareness as well as new possibilities for economic growth, waste management started to receive due attention. Various initiatives have been taken by government, NGOs, private companies, and local public in the past few decades to aware the public to understand the harmful effect of waste and its proper disposal methodologies based on organic, inorganic, hazardous, and nonhazardous nature. The waste can be classified as solid waste originating from vegetable waste, kitchen waste, household, etc.; e-waste originate from discarded electronic devices such as computer, television, music systems, etc.; liquid waste from water used for different industries, tanneries, distilleries, thermal power plants, plastic waste from plastic bags, bottles, bucket, etc.; metal waste from unused metal sheet, metal scraps, etc.; and nuclear waste from unused materials from nuclear power plants. Further, all these wastes can be grouped into wet waste (i.e., biodegradable) and dry waste (i.e., nonbiodegradable). The biodegradable wastes are kitchen waste including food waste of all kinds—cooked and uncooked, including the eggshells and bones, flower and fruit waste, including juice peels and house plant waste, garden sweeping or yard waste consisting of green/dry leaves, sanitary wastes, green waste from vegetable and fruit vendors/shops, waste from food and tea stalls/ shops, etc. Similarly, nonbiodegradable wastes are paper and plastic of all kinds, cardboard and cartons, containers of all kinds excluding those containing hazardous material, packaging of all kinds, glass of all kinds, metals



Introduction to Energy From Toxic Organic Waste

3

of all kinds, rags, rubber, house sweeping (dust etc.), ashes, foils, wrappings, pouches, sachets and tetra packs (rinsed), discarded electronic items from offices, colonies viz. cassettes, computer diskettes, printer cartridges and electronic parts, discarded clothing, furniture, and other unused equipments. The United States Environmental Protection Agency (US EPA) incorporates hazardous waste into three categories. The first category is source-specific wastes, the second category is nonspecific wastes, and third, commercial chemical products. Generally, hazardous waste is waste that is dangerous or potentially harmful to health and the environment. Hazardous wastes can be liquids, solids, gases, or sludge. They can be discarded commercial products, like cleaning fluids or pesticides, or the by-products of manufacturing processes. Similarly, the nonhazardous waste is defined by the Department of Defense (DOD) and the EPA as the extravagant, careless, or needless expenditure of DOD funds or the consumption of DOD property that results from deficient practices, systems, controls, or decisions. In addition, abuse is the manner in which resources or programs are managed that creates or perpetuates waste and it includes improper practices not involving prosecutable fraud. The EPA defines solid nonhazardous waste as any garbage or refuse, sludge from a wastewater treatment plant, water supply treatment plant, or air pollution control facility and other discarded material, including solid, liquid, semisolid, or contained gaseous material resulting from industrial, commercial, mining, and agricultural operations, and from community activities. The definition of nonhazardous waste can also include financial waste. In 2009, the US Presidential Executive Order, Reducing Improper Payments and Eliminating Waste in Federal Programs was initiated to eliminate payment error, waste, fraud, and abuse in major Federal government programs due to public zero tolerance of fraud, waste, and abuse. This Executive Order is based upon a transparent, participatory, and collaborative, comprehensive framework between the government and public. There are common practices to dispose waste from ordinary people. But, disposal of waste is becoming a serious and vexing problem for any human habitation all over the world. Disposing solid waste out of sight does not solve the problem, but indirectly increases the same manifold and at a certain point it goes beyond the control of everybody. The consequences of this practice such as health hazards, pollution of soil, water, air, and food, unpleasant surroundings, loss of precious resources that could be obtained from the solid waste, etc. are well-known. That is why it is essential to focus on proper management of waste all over the world. Waste management has

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Energy from Toxic Organic Waste for Heat and Power Generation

become a subject of concern globally and nationally. The more advanced the human settlements, the more complex the waste management. There is a continuous search for wide-ranging solutions for this problem, but it is increasingly realized that solutions based on technological advances without human intervention cannot sustain for long and this, in turn, results in complicating the matters further. Management of waste which generally involves proper segregation and scientific recycling of all the components is in fact the ideal way of dealing with toxic waste. Waste management is a commonly used name and defined as the application of techniques to ensure an orderly execution of the various functions of collection, transport, processing, treatment, and disposal of waste. It has developed from its early beginnings of mere dumping to a sophisticated range of options including reuse, recycle, incineration with energy recovery, advanced landfill design and engineering, and a range of alternative technologies. It aims at an overall waste management system which would be the best environmentally and economically sustainable for a socially acceptable method. This not only would avoid the above referred consequences, but give economic or monetary returns in some or the other forms. Nonetheless, land filling is still the dominant waste management option for the United States as well as many other countries around the world. Landfill releases biogas by the decomposition of garbage. Biogas is composed of methane and carbon dioxide. Methane is a by-product of the anaerobic digestion of waste by the bacterial community, and these bacteria thrive in landfills with high amounts of moisture. Methane concentrations can reach up to 50% of the composition of landfill gas at maximum anaerobic decomposition. In developing countries, few landfills have the facility for methane recovery as the required capital for methane recovery installations is lacking. The methane gas seeps into porous soil surrounding the waste and eventually migrates into basements, posing an explosion risk. Carbon dioxide buildup may cause asphyxiation. Carbon dioxide is readily absorbed for use in photosynthesis, but methane is less easily broken down and is considered 20 times more potent as a greenhouse gas. For every metric ton of unsorted waste (containing 0.3 Mt. carbon), 0.2 Mt. are converted to landfill gasses. Of this gas, carbon dioxide and methane each comprises 0.09 Mt. It is believed that landfill gasses supply 50% of human-caused methane emissions and 2%–4% of all worldwide greenhouse gasses; this is clearly an area of concern in global environmental issues. The capture of methane from landfill gas (biogas) and its filtration by adopting either cryogenic separation, membrane separation, or chemical separation may lead to



Introduction to Energy From Toxic Organic Waste

5

energy extraction, and this methane gas can be used as a substitute for CNG and LPG for heat and power generation. Biogas and the renewable energy production from waste are laborintensive and can provide employment to people. The additional employment will, however, vary with trends in the labor markets of the countries. The jobs created thereby may be low value jobs, but in periods of high unemployment the positive job creation will be viewed with less skepticism. These options suit the developing countries as most of them have a large work force. On the other hand, if the community is involved in the renewable energy generation, then the workers can be drawn from the community where the project serves. This can improve the income distribution among the rural population and different income brackets. A significant population shifting to urban centers, one of the typical issues the developing countries had to tackle in the past few years, can be reduced. This removes the additional burden on the resources at the urban centers. In the case of biogas use for heat and power application, the conventional fuels can be conserved for future. The employment effects of renewable energy projects can be such as the direct employment in construction, operation, and maintenance; indirect employment of job creation in the supply chain supporting the projects; and induced employment created, because of the wages earned through direct and indirect employment spent on goods and services, thus creating jobs. It is well-known that waste management policies, as they exist now, are not sustainable for the long term. Thus, waste management is undergoing drastic change to offer more options toward more sustainability. These options give the hope of offering the waste management industry a more economically viable and socially acceptable solution to the current waste management dilemma. This book outlines various advances in the area of waste management and possibilities to extract energy from the wastes in different forms. This book also focuses on current practices related to waste management initiatives taken by many countries, and it also highlights some initiatives taken by the US federal government, states, and industry groups. The main objective of this book is to depict the adoption of the waste management strategies, which may give certain benefits to the mankind in the form of economic sustainability and clean environment. The toxic wastes generated from various sources such as municipal, food processing industries, textile industries, leather industries, biodiesel production industries, paper industries, and health care industries, or hospital waste are given attention and

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Energy from Toxic Organic Waste for Heat and Power Generation

broadly discussed with its suitable disposal methodologies and possibilities of useful energy extraction from it. Also, this book deals with the advanced approaches adopted for the treatment of hazardous waste and its molecular cracking for non-contamination to the environment. In addition, this book gives in-depth knowledge on heat and electricity generation from the wastes. The effects of techno-economic aspects of toxic waste management were discussed in this book.

CHAPTER 2

Toxic Waste From Municipality Aravind Sam, Debabrata Barik

Department of Mechanical Engineering, Karpagam Academy of Higher Education, Coimbatore, India

2.1 INTRODUCTION In general, anything which is not useful anymore are collectively given the name as wastes or garbage.The wastes are of different forms and are increasing at higher rate day by day due to the development of the world. The waste generation also depends on the population level of the region under consideration.The level of waste generated is higher even in low-populated regions due to the lack of waste management systems. The wastes are generated from all sorts of places, starting from residential, commercial, industrial, agricultural, institutional places, etc.; the wastes from such places are given names accordingly and each waste has its own characteristics. Their behavior in the environment also varies with the nature of its composition and based on what those wastes are made up of. Hence, it requires a proper understanding of wastes that are handled. In common practice, wastes are handled by the municipality of each region.Their work is to collect all sorts of waste and to dispose them properly. The wastes that are collected by the municipality are termed as the municipal wastes. These municipal wastes include wastes collected from residential areas. The wastes from residential areas are like spoiled food items, plastic covers or bags, dead batteries, glass bottles, tins, aluminum foils, broken electrical and electronic items, and garden wastes. The municipality also covers the handling of wastes generated by the hospitals, industries, and other commercial places. The wastes are classified in many ways. One such classification is like biodegradable wastes, recyclable wastes, inert wastes, e-wastes, composite wastes, hazardous wastes, toxic wastes, and biomedical wastes. The biodegradable wastes include green wastes and food and kitchen wastes. The recyclable wastes include materials like papers, cardboards, glass bottles, tin cans, aluminum cans and foils, metals, some type of plastics, clothes, tires, etc. The inert waste includes construction and demolition waste, dirt, rocks, d­ ebris, etc. The e-waste includes worn out electrical and electronic items such as washing machines, refrigerators, televisions, light bulbs, computers, mobiles, and clocks. The hazardous waste includes chemicals, batteries, aerosol cans, Energy from Toxic Organic Waste for Heat and Power Generation https://doi.org/10.1016/B978-0-08-102528-4.00002-X

© 2019 Elsevier Ltd. All rights reserved.

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Energy from Toxic Organic Waste for Heat and Power Generation

fluorescent lamps, wastes from chemical processing industries, fertilizers, etc. The toxic waste includes pesticides, herbicides, fungicides, etc. The biomedical waste includes used syringes, expired pharma products, human tissues, and all sorts of items that are used for human checkup in hospitals. As discussed above, each of the wastes is to be handled and treated accordingly to its nature of behavior. Almost all forms of wastes are handled by the municipality. The municipal waste management is the next scenario where they face many difficulties in handling such wastes. Most of the developed and developing countries are worried about the waste management, as the rate of waste generation is drastically increasing with increasing population. Each nation in the world has its own way of waste management system. The rate of generation of wastes is represented as kilogram per capita per day. This rate is increasing day by day. It reported that, people with low income are estimated to produce around 0.86 kg of municipal solid wastes on a daily basis. Current global municipal solid waste generation levels are approximately 1.3 billion tons per year and are expected to increase to approximately 2.2 billion tons per year by 2025. This represents a significant increase in per capita waste generation rates, from 1.2 to 1.42 kg per person per day in the next 15 years. However, global averages are broad estimates only as rates vary considerably by region, country, city, and even within cities. This level if goes on increasing, there will not be enough place to dump the wastes. Hence, effective waste management strategies are to be created and followed by the nations. Many nations have created their own strategies in handling the wastes. This led the nations in converting the wastes into some useful form. A variety of processes exist for waste conversions and management like recycling, composting, land filling, and energy recovery. In most of the developing and developed countries, the recycling process is carried out by humans, so called scavengers. But this method will not contribute much in reducing the wastes. This in turn might harm the humans involved in it, as the variety of wastes handled by them may be hazardous. Recycling is one of the way to reduce the waste to make valuable products. The other method is composting where the organic wastes are subjected to degradation and converted to compost. This is used as manure in the cultivation of plants. This method needs place, money, and some marketing strategies to sell them. But it does have some drawback as composting deals with bacteria; so health-related issues will arise if it is not properly handled. Landfilling is the other option which is followed in most of the  nation.



Toxic Waste From Municipality

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But  it has major environmental impacts like leachate formation, gas formation, and infections leading to health problems. Leachate is a liquid that contains all sorts of components that existed in the waste, which is very toxic and will affect the ground water. The wastes in the landfilling leads to decompose and other activities which produce gases like methane and ­carbon dioxide. Methane is highly flammable which is to be handled properly. Carbon dioxide is a greenhouse gas which is another major drawback. The landfilling is open to the environment, which in turn will cause infectious diseases for the people in and around those landfillings.

2.2  METHODS OF ENERGY RECOVERY FROM WASTES The other way of waste utilization is to recover energy they contain with them.The most used energy recovery methods are thermal conversions (incineration, fast and slow pyrolysis, gasification, production of refuse derived fuel (RDF)), biochemical (composting, vermicomposting, anaerobic digestion/biomethanation), and chemical conversions (trans-esterification and other processes to convert plant and vegetable oils to biodiesel). Choice of conversion process depends on the type, property and quantity of biomass feedstock, the desired form of the energy, end use requirements, environmental standards, economic conditions, and project-specific factors.

2.2.1  Thermal Conversions Combustion, gasification, and pyrolysis are the thermal conversion processes available for the thermal treatment of solid wastes. As shown in Fig.  2.1, different by-products are produced from the application of these processes and different energy and matter recovery systems can be used to treat these products. 2.2.1.1 Incineration Incineration is a general technique for management of waste, as it reduces waste by around 70% in mass and 90% in volume. This also recovers energy by utilizing the heat content in converting water into steam to run a steam power plant. Fig. 2.2 shows the layout of an incinerator [2]. This system comprises of a lined furnace, fire grate, and air blowers and ranges in capacities from 50 kg to 20 tons per hour. Incineration process takes places between 750°C and 1000°C and it is coupled with steam and electricity generation process. Mass incineration without pretreatment of the municipal solid waste with electricity generation is regarded as the most reliable

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Energy from Toxic Organic Waste for Heat and Power Generation

Conversion technology

Primary products

Product recovery Extraction

Char

Secondary products Chemicals

Upgrading

Pyrolysis

Gasoline Synthesis

Tars & oils Gasification Gas

Combustion

Heat

Energy recovery

Methanol

Gas turbine

Ammonia

Engine

Electricity

Boiler

Fig. 2.1  Thermal conversion process and its by-products [1]. Power export Air cooler Electricity

Imported electricity

Expanded steam

Superheated steam

Heat utilization

Combustion chamber

District heating

Catalytic filter Electrostatic precipitator

REMEDIA

Superheaters Waste

HRSG

Boiler Economizer

Natural gas Air preheating system Energy recovery from steam

Energy recovery from flue gas

Wet scrubber

S T A C K

Process steam Condensate Air

Ash

Fig. 2.2  The layout of an incinerator [2].

and economical option due to the following reasons. (i) Most of the wastes will burn without giving rise to noxious products of combustion (HCI, HF, SO2, and NOx) in significant quantities. (ii) The volume and mass occupied by the waste is greatly reduced. A small volume of incombustible residues is left. The heat of combustion is recovered in a waste heat boiler for steam



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generation. (iii) Waste in its initial form may be objectionable in nature, containing decaying organic matter and whatever [3]. The by-product from the incineration is used as supporting materials in the civil engineering constructions.Their granularity nature and dense characteristics make them a substitute for the aggregates used in road construction [4]. The residue also finds its application as a precursor of alkali-activated materials, as an adsorbent material for the removal of hazardous elements from wastewater and landfill gases, as a soil replacement in agricultural activities, as partial or complete substitute of raw materials for the manufacture of ceramic-based products, as landfill cover, and as a biogas production enhancer. The residue may contain hazardous components like lead, zinc, and other heavy metals. The fly ash can be recycled by hydro-cyclonating them to remove fine particles of such hazardous materials [5].The residue from the incinerator is mixed with cement and used in light weight constructions. The usage has shown increased strength in the constructed item [6]. 2.2.1.2 Pyrolysis Of the disposal methods, pyrolysis of wastes, a thermal method of treatment requiring the heating of wastes in an oxygen-free atmosphere, is of interest. Various advantages claimed of the pyrolysis process are: (a) significant reduction in volume of the waste(1000