Effect of temperature on anaerobic-aerobic biodegradation of palm oil mill effluent - a preliminary study

Abstract

This study presented a preliminary study on the effect of temperature on anaerobic-aerobic biodegradation of palm oil mill effluent using lab scale anaerobic digesters and aerobic bioreactors. POME was anaerobically digested at ambient temperature (30 ± 1 °C). mesophilic (36 ± 1 °C) and thermophilic (55 ± 1 °C) conditions, respectively, followed by aerobic degradation at room temperature. Superior performance of thermophilic digester was observed in terms of biodegradation rate and solids reduction. The experimental results showed that the performance of aerobic bioreactors were affected by the anaerobic treatment conditions. Room temperature digested POME was slightly more accessible to COD, TSS and VSS removal than others; whereas thermophilic digested POME was easier to be biodegraded than others. Aerobic degradation of anaerobically digested palm oil mill effluent was possible to meet the local discharge standard.