Solid Waste Management
The common man’s perception about solid waste management suffer “not in my backyard” syndrome and leave waste to be taken care by other people only. The active participation of the common people in India is essential to manage the difficulties of source segregation, storage, collection, relocation, carry-age, processing and reutilization of burgeoning solid waste. It is urgent need to promote, awareness towards safe disposal of waste, public-private partnership, and selection of appropriate technology according to waste characteristics for resource recovery as well as energy generation in near future. Planning Commission Report (2014) reveals that 377 million people residing in urban area generate 62 million tons of municipal solid waste per annum currently and it is projected that by 2031 these urban centers will generate 165 million tons of waste annually and by 2050 it could reach 436 million tons. To accommodate this amount of waste generated by 2031, about 23.5 × 107 cubic meter of landfill space is required and in terms of area it would be 1,175 hectare of land per year. The area required from 2031 to 2050 would be 43,000 hectares for landfills piled in 20 meter height and could be an acute challenge for agricultural based Indian economy, health and sustainable environment. To confront this gigantic issue, some remedies have already recommended by the scientist and environmentalist. At first the source of waste generation, disposal and characterization followed by collection and storage has to be achieved and then the solid waste has to be segregated according to their composition. The two leading innovative mechanisms of waste disposal being adopted in India include composting (aerobic composting and vermi-composting) and waste-to-energy (WTE) (incineration, pelletisation, biomethanation). WTE projects for disposal of municipal waste management are a relatively new concept in India. Although these have been tried and tested in developed countries with positive results, these are yet to get off the ground in India largely because of the fact that financial viability and sustainability are still being tested. Composting is the decomposition of organic matter by microorganism in warm, moist, aerobic and anaerobic environment. Composting of municipality solid waste is, therefore, the most simple and cost effective technology for treating the organic fraction of solid waste. It is suitable for organic biodegradable fraction of waste, containing high proportion of lignocelluloses materials, which do not readily degrade under anaerobic conditions, waste from slaughterhouse and dairy waste. Vermicomposting is a system for turning organic waste into nutrient rich soil as it is processed by worms. It cannot really be described as a type of composting, which is a heat producing process that would actually kill worms; whereas vermicomposting should establish environment in which worms can thrive and reproduce. The worms process organic waste excreting them as organic material rich, stable, and plant-available nutrients that look like fine textured soil. Nutrients in vermicompost are often much higher than traditional garden compost. Bio-methanation is the process (two stage: acidification and methanation) of conversion of organic matter in wastes to methane and manure by microbial action in the absence of air through a process called anaerobic digestion. The solid wastes from agro-based industries have high organic content and hence its treatment by the process of bio-methanation is most viable as it produces useful products like biogas and enriched manure. Other useful techniques such as, incineration, pyrolysis etc will be discussed in the future to get rid from this demon. At the end of day the entire civilization should try to minimize nondegradable waste generation because higher the solid waste means more negative environmental impact. Therefore, to protect our Mother Earth 'Think Wise: Wastewise!
Dr. Kaushik Misra,
Dr. Arunava Sengupta
(Ex. Senior Research Fellow, IIT Kharagpur and IIT Kanpur),
Professor, Department of Chemistry
Techno India University, West Bengal