Biogas Production from Palm Oil Mill Effluent with Indigenous Bacteria

Abstract

POME or palm oil mill effluent is wastewater from the production of palm oil, which is produced by the sterilization, clarification, and hydrocyclone processes. The POME contains high carbohydrates, lipids, and protein which can contaminate the environment if it is not handled properly. The carbohydrates, lipids, and protein contained in the POME are potential for biogas production through the fermentation process with indigenous bacteria. The research aimed to study the impact of degradation time to the production of biogas in the bioreactor using the indigenous bacteria, KP1.2 (Stenotrophomonas rhizophila strain e-p10) capability from palm oil mill effluent.   The fermentation process was carried out in the anaerobic bioreactor with ranges of degradation time from 3 to 38 days to produce biogas. The bacterial population was calculated using a haemacytometer in which the number of bacteria was calculated in the small cubicles with a microscope. Biogas was saved in Tedlar bag and the biogas content was analyzed by Gas Chromatography (GC). The bacterial population increased along the fermentation period. The pH values range from 6.8 to 8.3. The highest bacterial population was 7.21 x 10⁷ cells/mL and the lowest one was 3.15 x 10⁷ cells/mL. The methane content, as well as, carbon dioxide content increased along the fermentation period. The highest methane content was obtained at 63.7 %moles and carbon dioxide was 22.5 %moles, while the lowest methane content was 33.5 %moles and carbon dioxide content was 19.5 %moles.