Abstract: The effect of powdered activated carbon (PAC) on the mixed liquor characteristics and membrane filtration resistance was studied by using two membrane bioreactors（Reactor 1 no PAC and Reactor 2 added PAC 500 mg/L）under the same influent and operating conditions. The results showed that adding PAC could effectively slow down the increase of viscosity，extracellular polymeric substances（EPS），tiny particulate content of the mixed liquid，and membrane filtration resistance. The membrane pore jamming model could be merged into the membrane self-resistance model，since the membrane pore jamming only worked in a very short time (≤1 min) and the particles bigger than the membrane pore and smaller than 1μm were the major matter of gelatin layer，which caused main filtration resistance.

摘要： 采用两组膜生物反应器（反应器1未投加粉末活性炭，反应器2投加粉末活性炭量为500 mg/L）研究了在相同的进水和运行条件下其混合液特性和膜过滤阻力的变化。研究发现：加入活性炭可有效延缓混合液的黏度、胞外聚合物（EPS）含量、微细颗粒的含量和膜过滤阻力的增加，而且黏度和EPS含量有较好的线性相关性。分析认为膜孔堵塞仅在很短的时间内（≤1 min）起作用，因此膜孔堵塞模型可并入膜本身阻力模型；大于膜孔径而小于1 μm的颗粒物是形成沉积层的主要物质，而沉积层阻力是膜过滤的主要阻力。