Basic Environmental Engineering That Covers the Syllabus of First Year Semester Scheme of the Rajasthan Technical University and Other Universities
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This page intentionally left blank Copyright © 2008, New Age International (P) Ltd., Publishers Published by New Age International (P) Ltd., Publishers All rights reserved. No part of this ebook may be reproduced in any form, by photostat, microfilm, xerography, or any other means, or incorporated into any information retrieval system, electronic or mechanical, without the written permission of the publisher. All inquiries should be emailed to [email protected] ISBN (13) : 978-81-224-2701-1 PUBLISHING FOR ONE WORLD NEW AGE INTERNATIONAL (P) LIMITED, PUBLISHERS 4835/24, Ansari Road, Daryaganj, New Delhi - 110002 Visit us at www.newagepublishers.com Dedicated to the Memories of My Beloved Brother Rajoo & Sister Mrs. Lata Sharma. This page intentionally left blank PREFACE Environmental engineering is one of the most popular, complex and fast growing disciplines in engineering. The scope of environment includes issues from public health, aesthetics, and impact of all development activities, pollution control legislation, standards, regulations, guidelines and their enforcement. Traditionally the application of engineering principles for the protection and enhancement of the quality of environment and protection of public health was called as sanitary engineering or public health engineering. Around 1968 this was changed to environmental engineering. For conceiving environmental engineering, one has to consider the definition of engineering itself. Engineering may be defined as the application, under limits of scientific principles for the planning, design, execution, operation and maintenance of structures, equipment and systems for the development and benefit of the society. Here the word benefit is more important than the development. The so-called development in some cases may not be in real benefit of the society. The environmental engineer plans, designs, executes, operates and maintains the water, wastewater and solid waste management plants. Clean, bacteriologically safe, potable drinking water protects and enhances public health. Liquid and solid waste management is a necessary step for healthy living. They also deal with air pollution control. The resulting pure cleaner air is conducive to people’s good health and prevents the building and other materials from the harmful effects of air pollution. The environmental engineer cares for the energy requirements of the society and the ways and means to protect the environment against the various pollutions created through the production and consumption of various goods and comfort conditions. It is the duty of environment engineer to assess the environmental impacts of the various development and other activities. In general one has to work to have sustainable and holistic development. Of course there are always constraints of resources, knowledge, human nature, social and racial considerations that limit the achievement of these goals. Therefore the environmental engineering is defined as the application of scientific and engineering principles, under limits, for the protection and enhancement of the environment that includes the biotic and abiotic both components. The environment exists in dynamic equilibrium of its biotic (living) and abiotic (non-living) elements. The solar energy induced photosynthesis synthesizes the carbon as the plant tissue and we get matter in various forms from the trees. The carnivores, humans and animals consume the edible matter. They convert it into the energy required to sustain their lives. Their excreta comes near to the nature and the natural scavengers, bacteria and others convert it into inorganic matter like nutrients due to the biological decomposition. The roots of the plants, to form the edible matter again, extract these nutrients. Like this the nutrient cycle, material cycle, energy cycle and other cycles like hydrological cycle keep on existing until there is a great shock given by the human beings. (viii) “Nature has enough for satisfying everybody’s need but not for anybody’s greed”. Human beings have lost their natural wisdom in want of power to overcome the nature. Since mid century the word has lost nearly one fifth of the topsoil from its cropland, a fifth of its tropical rainforests and animal species. Rapid industrialization and urbanization has increased carbon dioxide levels to the point where global climate is being affected. The protective ozone shield is being depleted because of the chlorofluorocarbons. The forest, which is a complete ecosystem, is being converted into dead forests. The biodiversity is reducing everywhere in the world. Biodiversity gives strength to the ecosystem against crisis. Only a well-diversified community can sustain against the extreme conditions. In quest of comfort conditions and well-secured life we have adopted a system, which is completely away from nature. We have made computers for paper less office work but the energy in making and running the computers is more than the savings made. Of course there are other advantages of computers in computation, up keeping of data etc. But the materials used in making the computer and the disposal of the obsolete ones are drastically against the environment. The quest of more and more comfort has fetched us far away from natural environment. The input of energy in building sector is increasing day by day. The requirements of both heating and cooling are becoming more and more energy exhaustive. At present the energy requirement in whole world is mainly met by fossil fuels. Nature has created the coal and petroleum in millions of years and we have exhausted them in hundreds of years. In the last 300 years we have consumed most of the coal and almost all of the petroleum products. Out of the 1,30,000 MW installed capacity of electricity production in India about 66% is by fossil fuels (coal+ petroleum products), 24% by hydropower, 4% by nuclear means and only 6% by renewable energy resources like solar, wind, biomass including small hydropower plants. Still there is a very large potential of renewable energy resources unutilized but the present availability of fossil fuels and the present high cost of electricity production through R.E.S. has restrained their share to only 6%. With the advancement of technology and scarcity of fossil fuels the cost of RES will come down and there share shall increase, but is it the sustainable development? In modern context the idea of sustainable development immerged in the Earth Summit at Rio-De-Janeiro in June 1992 that let us plan a development in which the generations to come, may not become deprived of the resources which we are using today. To achieve this aim we have to control our present rate of consumption of the available resources like the fossil fuels, ground water and conserve the bio diversity and the natural cycles like the hydrological cycle. While considering the production, consumption or utilization we have also to consider the other part that is pollution. Mixing of unwanted hazardous elements in anything is known as pollution, like mixing of sewage in fresh body of water, mixing of gases, like oxides of nitrogen, oxides of sulphur etc. in the air, increase of noise level etc. Actually the present trend of living is a serious cause of creating pollution in all spheres of life. Today the prosperity, wealth or living standard of a country is measured in terms of the per capita electricity consumption per year. That way India with its per capita consumption of 350 Kwh per year is considered far behind the U.S. which has around 20 times more than this. The advancement of a society is measured in terms of the measures of comfort like air conditioners, or conveyance like bigger and bigger expensive luxury cars. Taller buildings, more and more precious artificial fabric and so on. Production and maintenance of all these has created so much land, water and noise pollution that has overcome the advantages of all these so called advancements. Thus the challenging aspect of environmental engineering is to make balance between the rapid changes in the field of science, technology, health etc. and the very existence (ix) of life. Though environmentalism or the environmental consciousness is ancient the environmentalism became an organized force only in 1960s. It started with the publication of the book Silent Spring by Rachel Carson on the pesticide DDT in 1962. Actually the exponential growth of population and the worldwide consumerism imposed a great load on earth’s natural resources and waste management systems. This text aims at the fundamental, primary knowledge for every one who has a concern about environment. The chapters have been designed to quench the thrust of knowledge of a person, let it be a scientist, an engineer or any one who is concerned about protection of environment and thus a well wisher of society. This book has been written after gaining 10 years experience of working in the public health engineering department of Rajasthan and 20 years experience of teaching civil engineering students, subjects like environmental engineering, ecology and environmental dynamics, solid waste management etc. Recently environmental engineering has been introduced as a primary course common to first year students of all branches who opt for it. This text is on basic environmental engineering that covers the syllabus of first year semester scheme of the Rajasthan Technical University and other universities. Some portion of the martial presented in this book has bean derived from the work of others, their contribution is greatly ackoweldged. The recommendation of manual of water supply and treatment, manual on Sewerage and Sewage Treatment and manual on Solid Waste Management prepared by the Central public Health and Environmental Engineering organization, Government of India, Ministry of urban development have been closely followed. I acknowledge my debts to my parents for their blessings, my wife Bharati for her constant support, my daughter Ruchira for her help on computer, my son Saurabh and daughter-in law Surabhi for encouragement. I express my deep sense of gratitude to my teacher Prof.