Canadian Journal of Pure & Applied Sciences

Abstract: Globally, Nigeria is one of the largest producers of palm oil however the effluents generated from palm oil mills are usually discarded into the water bodies thereby causing environmental pollution. Serious efforts are made in the treatment before discharge into surface waters. This work is aimed at studying the kinetics of anaerobic digestion of palm oil mill effluent (POME) in a batch reactor at mesophilic condition. The digestion period lasted for 40 days. Maximum biogas production of 19.50% was obtained at hydraulic retention time of 10 days. Temperature has a significant effect, particularly on the performance of biogas-forming bacteria. Micro-organisms grew as temperature increased from 28 to 34oC after which the growth started decreasing. The percentage total suspended solid (TSS) and the effluent substrate concentration decreased as hydraulic retention time increased. The kinetics of anaerobic digestion of palm oil mill effluent followed a first order kinetic model with a first order reaction constant of 1.306day-1. The maximum rate of utilization (K), half velocity constant (Ks), endogenous decay constant (Kd), microbial growth yield (Y) and maximum specific growth rate ?max were found to be 0.868day-1, 97.66mg/l, 0.344day-1, 0.550 and 0.477day-1 respectively. Values of K and Ks suggest that the digesting microbes require much retention time to regenerate and hence inoculation is needed for better performance.