Performance of anaerobic membrane bioreactors (AnMBRs) with different concentration of powdered activated carbon (PAC) at mesophilic regime in membrane fouling control

Powdered activated carbon addition for fouling control in anaerobic membrane bioreactor

“…For determination of an optimal PAC dosage, a short-term study was implemented with three different PAC dosages, since the excessive dosing could cause more membrane fouling due to PAC being a potential foulant. While 2.5 of the PAC to biomass ratio with 5 g/L of PAC and 2 g/L of MLSS in the previous study showed the best flux improvement, the range of PAC dosages in recent studies regarding PAC addition to AnMBR was 0.4-5 g/L which had less than 1 of PAC to biomass ratio (Akram and Stuckey, 2008;Baêta et al, 2013;Chong, 2015;Park et al, 1999). Thus, the three PAC dosages for the optimisation were determined to be 1, 3, and 5 g/L, within the range of MLSS of the AnMBRs.…”

“…Journal Pre-proof increase, 5 g/L of PAC addition presented almost 25 kPa. This could mean that membrane fouling has not been reduced due to the insufficient PAC doses, however, the highest PAC dosage facilitated more stable sludge properties by effective adsorption and subsequently enlarged floc size (Chong, 2015). In conclusion, based on the best nutrient and COD removals as well as membrane fouling control, 5 g/L of PAC was found to be the optimal dosage for conventional AnMBR, and consequently added for long-term operation of AnMBR.…”

“…As a fouling control strategy for membrane bioreactors, pretreatment of feed water, such as acid, alkaline, ozone pretreatment, and the addition of fouling reduction enhancers, have been widely applied in many former studies. The addition of adsorbents and flocculants as fouling reduction enhancers, such as activated carbon, biochar, and zeolite, into AnMBR could enhance the reactor's removal performance and effectively alleviate membrane fouling as well (Chen et al, 2020;Chen et al, 2019a;Chong, 2015). Powdered activated carbon (PAC), which is comparatively simple and effective in its adsorption ability, has been broadly applied to aerobic and anaerobic MBRs for membrane fouling alleviation.…”

A review on membrane fouling control in anaerobic membrane bioreactors by adding performance enhancers

“…The active biofilm continues to biodegrade organic compounds as well as to reduce the attachment of microorganisms on the membrane surface so that it can relieve the membrane biofouling [12,24]. In addition, the scouring effect of PAC also alleviates membrane fouling, as it can remove the deposited cake layer on membrane surface while limiting the accumulation of foulants [25]. Figure 1 illustrates the mechanism of fouling reduction when activated carbon is added.…”

“…On the other hand, when the more PAC concentration of 4 g/L was added, the SMP was rather accumulated while having excellent COD and colour removal efficiency [33,34]. Several studies have revealed that the PAC addition not only decreased turbidity and colour, but also removed potential foulants such as fine colloids and soluble microbial products (SMP), which could lead to the reduction of fouling layer thickness [25,26,35]. Table 1 summarizes the effects of PAC addition on membrane fouling control in submerged AnMBRs.…”