Monticha Pechsuth, Poonsuk Prasertsan, and Masao Ukita

pp. 779 - 787

Abstract

Palm oil mil effluent (POME) contains high amount of organic matter, oil & grease, total solids and
suspended solids. Anaerobic treatment of POME was conducted at room temperature (30±2ºC) and high
temperature (50±0.5ºC). The effects of hydraulic retention time (HRT), organic loading rate (OLR), COD:N
ratio and temperature on the anaerobic digestion of POME were investigated. The optimum conditions were
found to be 10 days HRT, OLR of 9.50 kg COD m-3d-1, COD:N ratio of 65 and the optimum temperature at
50ºC. The highest COD reduction of 81.1% was achieved. Biogas production in general was greater than 0.30
m³
/kg COD/d. Comparison on anaerobic treatment using POME and POME treated by thermotolerant
polymer-producing fungi Rhizopus sp. ST4 revealed that the biopretreated POME gave higher COD removal
(72.6%) but lower biogas production (0.97 m³
/m³
/d or 0.27 m³
/kg COD/d) than the POME without pretreatment (56.1% and 1.16 m³
/m³
/d or 0.37 m³
/kg COD/d, respectively).