膜生物反应器次临界通量运行的膜污染特性研究

膜生物反应器（MBR）是将膜分离与生物反应相结合的污水处理新工艺，近年来已引起广泛的关注，但不可避免的膜污染限制其更广泛的应用。临界通量在膜污染控制中是个非常重要的概念。本试验研究平板膜生物反应器在次临界通量运行下的膜污染状况，并结合膜污染模型进一步表征膜表面的污染特性。试验结果表明。该平板膜生物反应器在次临界通量运行的情况下，膜污染可分为膜污染缓慢发展阶段（第Ⅰ阶段）和膜污染迅速发展阶段（第Ⅱ阶段），可分别用膜孔堵塞模型和泥饼阻力模型表征膜阻力与时间的变化关系。同时，对运行后的膜阻力分布进行分析，表明泥饼阻力和孔道吸附堵塞阻力是膜污染的主要组成部分，分别占到总阻力的73％和24％，而膜本身阻力仅占3％。

Study on membrane bioreactor fouling in sub-critical flux operation

Membrane bioreactors (MBRs), in which membranes are applied to biological wastewater treatment, have been greatly developed recently, but membrane fouling in MBRs restricts their widespread use. Critical flux is an important parameter to control membrane fouling. This study investigates the change in membrane fouling in a flat membrane bioreactor operating at a sub-critical flux. The previous theoretical models are used to simulate the membrane fouling characteristics. Experimental results show that membrane fouling can be divided into two stages: the first period during which fouling gradually occurs and the second period in which fouling rises rapidly. The pore blocking resistance and cake resistance models can be used to simulate resistance with time in different periods. The analysis of membrane resistance distribution shows that resistance arising from cake formation is 73% of total resistance, resistance due to pore blocking is 24%, and clean membrane resistance is only 3%.