Investigation on the performance of hybrid anaerobic membrane bioreactors for fouling control and biogas production in palm oil mill effluent treatment

The performance of three different sizes of powdered activated carbon (PAC) added in hybrid anaerobic membrane bioreactors (AnMBR) was compared with a traditional AnMBR without PAC in treating palm oil mill effluent. Results showed that AnMBR with PAC performed better than the AnMBR without PAC. It was also found that adding a relatively smaller size of PAC enhanced the chemical oxygen demand removal efficiency, while the concentration of mixed liquor suspended solid and mixed liquor volatile suspended solid were 8,050 and 6,850 mg/L, respectively. The smaller size of PAC could also enhance the biofloc formation and biogas production. In addition, the smaller particle sizes of PAC incorporated into polyethersulfone membrane resulted in higher performance of membrane fouling control and produced better quality of effluent as compared to the membrane without the addition of PAC.