Compositing of solid waste with special emphasis in vermiculture

Abstract

The composting process is currently conceived primarily as a waste management method to stabilize organic waste, such as manure, municipal biosolids, and organic urban wastes. Composting is a natural process whereby organic material decomposes into a dark nutrientrich soil amendment .The stabilized end-product (compost) is widely used to improve soil structure, provide plant nutrients, and facilitate the revegetation of disturbed or eroded soil. Vermicomposting uses earthworms to turn organic wastes into very high quality compost. The use of worms speeds up the process of decomposition to produce a richer end product. Vermicomposting is especially useful for processing food waste since the worms consume the material quickly and there are fewer problems with odor. Vermicompost consists mostly of worm casts (poop) plus some decayed organic mailer Characterization of MSW is important to evaluate its possible environmental impacts on nature as well as on society. The MSW can be characterized as the high content of organic mailer which indicates that the MSW is superior for vermi composting in Bangladesh. From the study, it has been found that percentage of organic waste is more than 80% and most of them are vegetables and food waste. The various controlling parameters of vermi composting are collected from the materials and digestion processes. Vermicomposting is carried out at relatively low temperatures (under 25 cC). It is vitally important to keep the temperature below 35 cC; otherwise the earthworms will be killed. Chemical analysis and microbial analysis also has been doile to know the nutrient content and existence of pathogenic bacteria in the final compost. It is found that it is rich in nutrient and no pathogenic bacteria have been found. Vermi composting process is much faster than windrow composting process. Vermi compost can be ready within one month. Growth rate of worms are determined which shows that an initial stock of I kg of worms can become 9 kg after one year. Finally the financial involvement for vermi composting plants are evaluated and found the economic feasibility of them.