Composting of municipal solid waste

THE CITY OF COLOMBO , which has a resident population of little over half a million, and a total area of 3731 hectares, is administered by a Municipal Council. The collection and disposal of solid waste generated within the City is a function of the Municipal Council, and is carried out by its six district offices. The Colombo Municipal Council (CMC) collects around 500 metric tons of solid waste daily. The practice of disposal of this waste has, over the years, been dumping on open land, lowlying marshy areas within the city being used for this purpose. With the increase in the generation of garbage, and the diminishing supply of available land, the CMC was faced with the problem of finding new land for waste disposal. Sanitary landfilling, with compaction of the deposited waste , recovery of resources from the waste and composting of solid waste, thereby reducing the quantity of waste to be disposed of, and thus lengthening the lifespan of the existing landfills, was identified as one possible solution to this problem. This study was undertaken to determine the feasibility of composting the solid waste collected by the CMC. The study was made up of three parts: (i) a survey of the production of compost in Sri Lanka on commercial basis (ii) a literature survey on composting and (iii) a pilot study on the feasibility of composting the CMC solid waste. This paper looks at the findings of the first two parts of the study very briefly, and focuses on the findings of the third part, which is the pilot study.