Study of Biogas Production with Organic Rubbish as Producing Material

This research had done at Production and Agricultural Machines and Equipments Management Laboratory at Agricultural Engineering, Faculty of Agricultural Technology, Andalas University, Padang City from November 2011 to March 2012. It intent to study about biogas physics parameters (to know about when the first time it producing biogas, biogas volume and pressure, relative humidity (RH), enviroment temperature, biogas energy) and chemical parameter such as producing material acidity degree (pH) in the beginning and last obsevation. It obsevation method has two different ways. First, using combination of 35 kgs radish and 35 cabbages rubbish as producing material. Second ways is using 70 kgs radish rubbish. Each way mixed by 4 liters EM4 as decomposer, 70 liters water, and observed for 30 days. The result showed in first way that biogas had produced first time at 9th day with 554,4 kJ biogas energy,  productivity is 0.47 liter biogas / kg producing material, 28.6 oC enviroment temperature, 80.1 % RH, 456.1 Pa biogas pressure, 6.1 starting pH, and 6.6 last pH. In second way had obtained that in 9th day is first time biogas had produced with 537.6 kJ energy, productivity is 0.42 liter biogas / kg producing material, 28.2 oC environment temperature, 82.1 % RH, 436.2 Pa biogas pressure, 6.3 starting pH, and 6.8 last pH.