该文研究了两种不同孔径的聚偏氟乙烯中空纤维膜生物反应器(MBR)在城市污水处理过程中不同外界因素对膜污染的影响.研究表明造成膜污染的主要因素有活性污泥特性、胞外聚合物(EPS)、膜孔径等.试验发现,膜的过滤性能下降并不完全由污泥浓度影响,真正造成膜过滤性能的下降可能是由于污泥自身性质的改变.随着污泥浓度的增加引起粘度的增加,从而加重的膜的污染.EPS越大,膜通量越小.EPS在膜反应器中不断积累,改变膜面沉积层的孔隙率和结构,引起膜污染.膜孔越大,滤饼层污染越迅速,通量的衰减越快.膜通量初期的衰减速率与膜孔径有关,而最终的稳定通量却与膜孔径无关.%Paper investigated the external factors effected on membrane fouling of two different membrane aperture PVDF hollow fiber membranes bioreactor in municipal wastewater treatment process. Results indicated that membrane fouling was affected by activated sludge properties extracellular polymeric substances (EPS) and membrane aperture but not totally the concentration of sludge. With the effect of activated sludge, the decline of membrane filtration ability was mainly ascribed to the variation of sludge properties but not the concentration of activated sludge. The sludge viscosity increased under the condition of activated sludge concentration increment, and then the membrane filtration resistance increased as well as membrane fouling severed. It was also found that more EPS quantity, the smaller membrane fluxes. With the accumulation of EPS, the void ratio and structure of deposit on the surface of membrane were changed. Big membrane aperture could make quick membrane fouling and flux decline. Though the flux decline had the relationship with membrane aperture in the filtration primary stage, the final stable flux was not affected by membrane aperture.
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