The effectiveness of anaerobic digestion process by thermal pre-treatment on food waste as a substrate

Thermal pre-treatment is necessary for the feedstock of Anaerobic Digester (AD) to improve the degradation process. This study aims to investigate the effect of thermal pretreatment on Food Waste (FW) as a substrate through Biochemical Methane Potential (BMP) test followed by pilot scale using a continuous stirred tank reactor (CSTR) digester. TS, VS, COD, SCOD, and solubilization samples were measured during on CSTR reactor. FW was pretreated by heating at 70 degrees C, 90 degrees C, and 120 degrees C for 45 minutes. Results showed that thermal pre-treatment at 70 degrees C had the most effective digestion process with TS, VS, COD reduction of 8.26%; 2.54%; and 14% and increase SCOD and solubilization of 10.2% and 24.7%, respectively compared to thermal pre-treatment at 90 degrees C and 120 degrees C (p<0.05). Therefore, thermal pre-treatment at 70 degrees C was chosen for AD pilot scale in this study. Meanwhile, pilot scale experiment showed the results that thermal pre-treatment at 70 degrees C was obtained significant differences of 31% TS; 38% VS; 42% COD; 23% SCOD; and 30% solubilization compare with without thermal pre-treatment (p<0.05). Pre-treatment with thermal on FW as a substrate may help in increasing the degradation process at the hydrolysis phase in order to increase the effectiveness of the process in AD reactor.