A study of palm oil mill effluent treatment using a pond system

Abstract

Palm oil mill effluent (POME) contains a high concentration of organic matter. COD concentration is in the range of 45,000 to 65,000 mg/l, 5-day BOD 18,000 to 48,000 mg/l and oil and grease greater than 2,000 mg/l. The COD:N:P ratio is around 750:7.3:1. The nutrient content is low for aerobic treatment processes but sufficient for anaerobic treatment processes. This paper evaluates the treatment efficiency of a pond system consisting of 8 ponds in series treating 600 cu m/day of POME. The pond system has been in operation since the mid 1980's. Effluent COD was 1,725 mg/l, BOD 610 mg/l, ammonia-N 115 mg/l, nitrate nitrogen 5 mg/l, TKN 200 mg/l and phosphate 60 mg/l. The effluent was not able to meet the discharge standard of 50 mg/l BOD.