Design and Development of Portable Household Biogas Plant

Energy is one of the prerequisites for the growth of agriculture and industry. The growing global awareness of the energy crises has brought us to the beginning of what might be called as the "recycle revolution". Biogas as an alternative source of energy has been widely recognized in a number of countries of the various alternative sources of energy. Biogas energy assumes a major role with special reference to the rural sector. Biogas is generated by anaerobic digestion using cow dung, methane content of the gas produced from the digestion of the cattle varied from 60 to 72 per cent, the remaining being carbon-dioxide. The feed material cow dung and kitchen waste selected for experimental study was analyzed for physical and chemical characteristics using standard procedure. A cylindrical shaped floating drum type biogas plant which gives constant gas pressure, less scum problem, higher gas production per cubic meter of digester volume and less leakage over fixed dome type plant. The biogas digesters work safely up to a pressure range of 0.05 kg/cm² (50 m bar). Hence, the pilot size biogas plant designed will operate safely. The pressure developed inside the gas holder was measured by using the Borden type pressure gauge (0-2 kg/cm²). The temperature of gas was measured by handheld thermometer (0-110° C). The cow dung, kitchen waste and water is mixed in definite proportions on weight basis to bring the total solid. The amount of gas produced in 24 hours was measured daily from gas holder till 40 days of experiment. The experimental result indicated that 6 to 8 per cent of digester volume added with inoculums before feeding the material increased the biogas production. It was noted that combination gas production from slurry combination was 350.99 liters in 2.08 size digester at the end of retention period of 56 days.