DECENTRALIZED INTEGRATED ORGANIC WASTE MANAGEMENT FOR URBAN AREAS IN THE DEVELOPING WORLD

摘要

Several urban municipal authorities in developing countries are increasingly opting for waste-to-energy projects for dealing with the increasing quantities of organic waste being generated in urban habitats. This involves raising awareness among residents about waste segregation or involvement of manual labor for segregation of collected waste, capital investment in space and infrastructure to convert a few tens of tons of organic waste into electricity, running expenses of waste transport and electricity supply to the point of use, etc. We have developed a decentralized integrated waste management system that allows organic waste to be managed at source, while providing an energy service to the local population. For a cluster of 100 houses, an above-ground floating-dome biogas plant is built on community-owned land to process about 50 kg organic waste. The 20-25 kg biogas produced is supplied to the kitchen of a local restaurant or canteen at a price less than the market price for the equivalent quantity of LPG. The effluent is used for organically fertilized intensive vegetable cultivation on community land, and the surplus slurry is supplied to local nurseries and individual terrace gardeners as liquid organic fertilizer. The operation can be managed by a group of waste pickers (already engaged in collecting and selling recyclable wastes to scrap merchants), with training and technical support provided by us. The economics of the system is attractive for the urban residents. The system also creates an opportunity to enhance income for waste pickers in urban areas.