Abstract

This study investigates the generation of biogas from cow dung using a constructed 10 m³ family-size digester at the National Center for Energy Research and Development, University of Nigeria, Nsukka. The cow dung was procured from Nsukka main market central abattoir. Production of biogas was monitored over a period of 20 days. Standard methods were used to determine pH, temperature, total viable counts, total solid, volatile solid, mould count, coliform count, ash content and moisture content of the digesting mixture. Results showed that cow dung commenced flammable gas production on the 2^nd day after charging the digester. Optimum gas production was recorded on the 7^th day. As digestion proceeded, pH increased to a maximum of 7.8 on the 7^th and 8^th day. Total viable counts increased by over 307%, while total solids and volatile solids decreased to 36.9 and 49.2% respectively. Result also showed that the waste produced maximum biogas within the optimum temperature range of 35 - 42^oC but at different periods. The biogas generated sustained cooking of three different foods daily for two weeks without exhausting.

Key words: Biomethane, anaerobic digestion, innoculum, digestate.