Biofouling is a key problem in membrane filtration, and extracellular polymer substances (EPS) play a key role in biofouling. Biofouling contributes to membrane fouling during ultrafiltration of up-flow biological activated carbon filter (UBACF) effluent. EPS are released when pollutants get attached with membrane surface and when pollutants are in solution phase from cell lysis and by cell secretions. In our study of EPS + humic acid (HA) prepared as the effluent pollutants for ultrafiltration, we found that EPS increased the interfacial forces between the pollutants and the membrane, resulting in membrane fouling. In the early stages of filtration, the main contribution of EPS to membrane fouling was to bond with organic colloids, which led to an increase in the pollutant particle size and zeta potential. This increased the short-range Lewis acid-base (AB) forces from −4.89 nN to −12.59 nN and accelerated the formation of a cake layer. In the late stage of filtration, the EPS increased both the AB and London–van der Waals (LW) forces, thus accelerating membrane fouling. In order to mitigate biofouling, we developed a method of pretreating the effluent with 0.4 mg/L ozone prior to ultrafiltration and backwashing with 8 mg/L H₂O₂ to sterilize bacteria attached to the membrane surface. This method not only changed the characteristics of the EPS, but also inactivated bacteria by disinfection with H₂O₂, thereby reducing the amount of EPS. The proposed method provided a long-term stable operation guarantee for ultrafiltration of UBACF effluent.

生物污染是膜过滤中的关键问题，而细胞外聚合物物质（EPS）在生物污染中起关键作用。在上流式生物活性炭滤池（UBACF）废水的超滤过程中，生物积垢有助于膜结垢。当污染物附着在膜表面时，以及由于细胞裂解和细胞分泌而污染物进入溶液相时，会释放EPS。在我们对用作超滤废水污染物的EPS +腐殖酸（HA）的研究中，我们发现EPS会增加污染物与膜之间的界面力，从而导致膜污染。在过滤的早期阶段，EPS对膜结垢的主要贡献是与有机胶体的键合，这导致了污染物粒径和ζ电位的增加。这将短程路易斯酸碱（AB）力从-4.89 nN增加到了-12.59 nN，并加速了滤饼层的形成。在过滤的后期，EPS增大了AB和伦敦范德华力（LW）的力，从而加速了膜的结垢。为了减轻生物污染，我们开发了一种在超滤之前用0.4 mg / L臭氧预处理废水的方法，并用8 mg / LH反洗₂ O ₂对附着在膜表面的细菌进行灭菌。该方法不仅改变了EPS的特性，而且还通过用H ₂ O ₂消毒而灭活了细菌，从而减少了EPS的量。该方法为UBACF废水的超滤提供了长期稳定的运行保证。