Investigation of biogas generation form solid wastes of a vegetable and cattle market

Abstract

There are many vegetable and cattle markets throughout the country producing tons of waste each day. Usually these wastes are dumped in nearby rivers, canals and roadsides resulting in tremendous pollution. There lies a probable solution to use these wastes to produce biogas which will not only minimize the pollution problem but also contribute to energy crisis mitigation. In this study, biogas generation from a large vegetable and cattle market waste was investigated. A large vegetable and cattle market in Shibchar, Madaripur was surveyed. Produced waste was separated and quantified. The selected market produces more than 2000 kg of waste on a weekly basis, 62% of which is biodegradable. The produced waste is either dumped into nearby lowlands or the river. Laboratory experiments for biogas production with the same composition of the waste found in the market were conducted to study the variation of gas production due to variation in conditions like temperature, feeding condition, solid concentration and number of chamber. Solid content of the waste, volume of reactor, produced gas, pH and composition of the gas were measured. It was found that the volatile solid content of this waste is 18.28 percent and the total solid content was 24.06 percent. Temperature played an important role in gas production. Rapid decrease or sustained low temperature resulted in low production. It was revealed that under favorable and stable condition, the average quantity of biogas yield was about 0.32 m3/m3/d for waste loading rate of 8.52 kg/m3/d. Produced gas contained 60.5% CH4, 17.5% CO2 and trace amount of H2S.