Evaluation of digester performanceusing the FOS/TAC analysis methodon biogas plant in Bali

Abstract

Most of the biogas power plants in Bali are built by the government through the SIMANTRI and Domestic Biogas (BIRU) projects. The two biogas plants follow the Chinese design model. They can only be used as small household biogas plants to meet their own gas needs for cooking and lighting. In this study, the ratio analysis of inorganic carbon (FOS) to volatile organic acid (TAC) (FOS / TAC) levels was used as an indicator to show the performance of the biogas plant. This provides an indication of how well the biogas power plant is being fed and operated. Attempting to have a FOS / TAC ranging from 0.3 to 0.5 should be one of the goals of the operator to ensure complete conversion of fermenter material to high methane yields. The FOS / TAC analysis did not show a trend of biogas feeding in the three observed digestion processes. In fact, each biogas plant was operated the same way, as there were no significant changes during the four FOS / TAC tests and the results were visible. It is assumed that all biogas plants are loaded differently. Feeding ranges from once daily to every 5th day, depending on the operator. Also, the amount of impurities given is around the inside of the biogas plant.