Effects of thermal pre-treatment on empty palm fruit bunch as co-substrate for palm oil mill effluent anaerobic digestion

Palm oil mill effluent (POME) is an ideal option as feedstock for biogas production by anaerobic digestion since it is abundant and problematic for the environment. This work tried to observe the anaerobic digestion of POME with empty oil-palm fruit bunch (EFB) as co-substrate. An inoculum containing POME-diluted cow manure was prepared. The EFB samples were pre-treated with a thermal process in an autoclave at 120, 150 and 200°C. The biogas production of the samples was measured for 31 days and compared to each other. The sample with the 200°C treatment process was observed to produce 139% more gas than the baseline. However, at 150°C, the pre-treatment yielded gas with the highest methane content of 40%. It can be concluded that the thermal pre-treatment process on EFB co-substrate has a beneficial impact on POME biogas production and quality.