Effects of pretreatments and different types of microbial starter on biogas production from food waste

The problem with the slow process of anaerobic biodegradation, especially in food waste, is that the rate of biogas production cannot keep up with market's high demands for fuel. Several studies have tried out to optimize the rate of biogas formation, such as the addition of microbial starters and pretreatments. The objective of this research is to examine the production and characteristics of biogas made of vegetable market waste added by EM-4 and GP-7 microbial starter using a single batch biodigester system. The specific target is to determine the performance of biogas production process by combining the two techniques. The methods used consists of the design and manufacture of batch system biodigesters, determination of raw material characteristics, preparation of raw materials by pretreatment and addition of starters, namely EM-4 and GP-7. By combining the two techniques, biogas production with greater volumes and concentrations of methane gas can be obtained in a relatively short period. Pretreatment with NaOH 3% solution and the addition of cow dung starter and GP-7 can increase biogas production with the largest methane content on the 45th day and reached 38.32% of CH4 while pretreatment with NaOH with starter EM- 4 and cow dung only reached 22.5%.