曝气强度对MBR活性污泥性质和膜污染的影响

Laboratory experiments on submerged MBR were carried out to investigate the influence of aeration on characteristics of the activated sludge and membrane fouling. Results showed that membrane fouling included 2 stages under different level of aeration, with the membrane fouling rate of MBR-B (0.6 m3/h of aeration ) higher than MBR-A (0.2 m3/h of aeration) in Stage 1 of the first 20 d, and lower in Stage 2 after 20 d. Different aeration led to viscosity discrepancy, which however didn’t show clear relationship with membrane fouling. It was found that mixed liquid suspended solids（MLSS）was no different in 2 MBRs, i.e., aeration didn’t play an important role on MLSS. The influence of aeration was important on loosely bound extracellular polymeric substances(LB-EPS) but not on tightly bound EPS (TB-EPS). LB-EPS and LB protein had strong positive effect on membrane fouling, which indicated that protein was the major pollutants.