Optimisation of the Aerobic Digestion Process in Palm Oil Mill Effluent (POME) Ponds

The palm oil industry in Malaysia is one of the industries that generates a high income. However, the increasing production of palm oil products also means increasing generation of palm oil waste which includes palm oil mill effluent (POME) that is very polluting to the environment due to the high biological oxygen demand (BOD) and chemical oxygen demand (COD) content. The present study focuses on the lab-scale ponding treatment of POME which is one of the most popular treatment methods in palm oil mills. The variable factors include oxygen concentration, pond depth and treatment duration. The experiment was designed using the Design- Expert software version 6.0.8 (Stat-Ease, Inc., Minneapolis, USA) using the response surface method (RSM) based on previous studies done on the variable factors chosen. The optimum conditions were found to be 0.5 vvm oxygen concentration, 10 cm pond depth and 5 days treatment duration for BOD removal (47.1%) and COD removal (42.9%). As for colour removal (13.5%), the optimum conditions were found to be 0.5 vvm oxygen concentration, 5 cm pond depth and 5 days treatment