Performance of hybrid anaerobic membrane bioreactors (Anmbrs) augmented with activated carbon in treating palm oil mill effluent (pome)

Abstract

Anaerobic membrane bioreactor (AnMBR) is an effective technology for the treatment of wastewater. However, the cost of membrane and membrane fouling has limited its application in wastewa-ter treatment on a commercial scale. Therefore, in this study, different particle’s sizes of powder activated carbon (PAC) were added into four identical AnMBRs to investigate their effects on chemical oxygen demand (COD) and natural organic matters (NOM) removals, mixed liquor suspended solids (MLSS) and mixed liquor volatile suspended solids (MLVSS) values, and membrane fouling control when treating of palm oil mill effluent. It was found AnMBRs with PAC performed better than the AnMBR without PAC. It was also found that the addition of a relatively smaller size of PAC (approximately 75 μm) enhanced the COD removal efficiency to 89.45 ± 2.48, while the concentration of MLSS and MLVSS were 21,420 and 16,452 mg/L, respectively, which was high enough to result in bigger floc size, lower NOM content and better membrane fouling control. Also, to investigate the performance of polyethersulfone membrane in fouling control, different concentrations of PAC had been incorporated into it. The results showed that integrated membrane with (5 wt.%) PAC was able to achieve up to 60% COD removal rate, compared to 38.6% without PAC. Besides, there was a trend where the membrane with a higher concentration of PAC integrated has a better performance in both membrane fouling control and pollutant removal ability.