Use of biogas from tofu industry for domestic use at Probolinggo City - Indonesia

Tofu industries produce by product of whey which is still rich in organic content. Tofu industry of using soy bean of 1400 - 1600 kg/day produces 25 m3 of wastewater per day of 6321 mg COD/liter. This high content of COD and volume of wastewater instead of potential pollution could be transformed into biogas and used by local communities for domestic purposes like alternative energy for cooking. This study is aimed to assess the possibility of using wastewater from tofu industry by local communities for cooking. Asri Tofu Industry with such typical production of wastewater was assessed to treat its wastewater while the by-product of biogas would be used by local communities for cooking. About 38 m3 biogas per day could be produced per day and can be used by at least 117 houses in the nearby factories not far from 300 m from the factory. The use of biogas would reduce local community expenses to buy LPG and woods for cooking.