(426f) Exergy Analysis of Solid Waste Management Opportunities in Indian Context

Increase in population, urbanization, economic growth, Industrialization, and change in the lifestyle in India had resulted in to increase use of the resources. Increased use of the material resources and its inefficient conversion in to useful work results in generation of waste. A huge quantity of Municipal Solid Waste (MSW) gets generated each year.  Most of the MSW generated is usually disposed of unscientifically in open dumps and landfills, creating problems to public health and the environment.  As per the 2001 census around 1billion India’s population lives in urban areas.  MSW generation in cities in India is found toincrease from 6 to 48 million tons from year 1947 to 1997 with an annual growth rate of 4.25%.  The present generation rate of MSW in Mumbai is estimated to be about 7500 tons while the state of Maharashtra as a whole generates about 16000 tons per day as estimated by a Planning commission report. In many cities more than half of the solid waste generated remains unattended.  It was estimated that the MSW generation and disposal resulted in the emissions of 12.69 million tons of CO2 eq. in 2007. Management of Municipal Solid Waste generated in cities of India is a cause of worry as far as environmental degradation is concerned. On the other hand the MSW contains high exergy content materials, which makes MSW as a potential energy source. The traditional way of management of these MSW is by dumping these wastes in a low-lying area called a landfill. Various energy recovery treatment methods are used for treatment of MSW, such as incineration, gasification, plasma treatment etc. Incineration includes direct combustion of waste while gasification includes converting the waste into a combustible gas by a gasification agent. Exergy analysis has been found to be an appropriate measure for material resource accounting as well as for accounting of the waste generated. Exergy gets lost in all real processes in the form of heat or physically, chemically or Nuclear radiation reactive substances.  Exergy lost in the form of chemically/physically reactive substances is found to have major role in the degradation of the environment.  The aim of this work is to analyze the MSW management in India using exergy analysis. In this work we will compare the various MSW treatment methods (Incineration, gasification, landfill, plasma treatment, etc.) on the basis of the exergy of all resource consumption, the exergy of the product output (in the form of electricity, methane gas, etc.) and the emissions. This assessment will provide the exergetic improvement potential in each of the disposal methods used which will lead to minimization of losses, emission and hence the environmental degradation. Outcome of the this work is expected to provide the insights in the exergetic potential of the MSW in India, its potential to harm the environment as well as the potential to energy conversion which may help to frame the future policies for MSW management in the country.