Preliminary study of biohydrogen production from POME with hydrolysis-acidogenesis reactor.

Palm Oil Mill Effluent (POME) is able to produce greenhouse gas and cause environmental problems if it is not managed properly. Anaerobic digestion is an outstanding method which has been proven to effectively manage this waste. However, due to the difference in growth parameters and biological kinetics of the various microorganisms in metabolic pathways, then anaerobic digestion process could be carried out in two-stage anaerobic digestion (TSAD), namely hydrolysis-acidogenesis and methanogenesis stages. TSAD has been proven to produce hydrogen-enriched biogas (10–30% v/v) with a profitable process. It showed better overall degradation rates and better biogas quality than the single stage. Hydrolysis-acidogenesis step produces hydrogen. It is a promising future energy carrier for sustainable green energy production because of its clean and non-polluting characteristics, being renewable, higher efficiency of conversion in power generation, and high density. This study focuses on the hydrolysis-acidogenesis, with hydrogen and carbon dioxide as gas products. This study aims to evaluate the preliminary production of biohydrogen in the hydrolysis-acidogenesis process by using POME. The biohydrogen quality was investigated by using stirred tank reactor under adjusted pH and temperature. The test was carried out using a stirred reactor with a capacity of 2.5 liter. POME and inoculum were fed into the reactor and then purged with argon gas to remove oxygen gas. The process was maintained at temperature of 35oC and pH of 5.5. Based on the biogas production, it was found that the hydrogen production at hydrolysis-acidogenesis was 32% and zero amount of methane gas. This theory is the basic for research in multi-stage reactors, that the optimization of hydrogen gas production in hydrolysis and acidogenesis reaction can produce better biohydrogen formation in terms of quality. The results of this preliminary study can be used as a reference for further studies in producing optimum hydrogen in a stirred anaerobic reactor. [ABSTRACT FROM AUTHOR]