混凝-膜过滤中滤饼层对双酚A的去除强化作用研究

以聚合氯化铝(PAC)和氯化铁(FeCl3)为混凝剂,分析了双酚A(BPA)在1g/L高岭土溶液混凝过程中的特征.并借助循环错流过滤强化污染层累积的方法,评价产生滤饼层的微滤(MF)膜对BPA的截留效果.结果表明:清洁的微滤膜过滤BPA溶液在短时间内达到截留吸附饱和,之后其对BPA的吸附截留作用显著降低;混凝絮体混合液经膜过滤时产生的污染层有利于BPA的去除,且单独混凝对BPA去除率最高的混凝剂投加量下进行膜过滤时的阻力较小.PAC混凝—膜过滤后BPA去除率比单独混凝提高了34.30%;FeCl3混凝—膜过滤后BPA去除率比单独混凝提高了28.38%.初始BPA浓度对混凝-膜过滤去除率有一定影响,BPA浓度为100μg/L时,比BPA浓度为5mg/L时采用2种混凝-微滤膜过滤方式去除率均有提高.

Enhanced removal of bisphenol A by the cake layer in coagulation-microfiltration process

Using polyaluminum chloride(PAC) and ferric chloride(FeCl3) as coagulants,the removal of bisphenol A(BPA) was investigated in coagulation process of 1g/L kaolin synthetic solution.The circular cross-flow filtration method to enhance the accumulation of membrane fouling was used to evaluate the BPA removal efficiency of the cake layer.The removal efficiency of BPA with clean microfiltration(MF) cut off decreased obviously when the adsorbed BPA reached saturation in a short period of time.The cake layer which was formed by the circular membrane filtration of mixture promoted the BPA removal,and the membrane resistance in circular membrane filtration reached minimum when removal efficiency of BPA was highest in a single coagulation process.In PAC coagulation-membrane filtration experiments,BPA removal efficiency was increased 34.30% than that in single coagulation;while in FeCl3 coagulation-membrane filtration experiments,BPA removal efficiency was increased 28.38% than that in single coagulation,indicating that the formation of cake layer has promoted the BPA removal.Also,the BPA removal efficiency for the initial BPA concentration of 100μg/L was 7% higher than that for the initial BPA concentration of 5mg/L by coagulation-circular membrane filtration.