通过在线投加混凝及粉末活性炭(PAC)处理,研究二者对超滤(UF)进水中有机物相对分子质量分布、亲疏水性的影响,考察在线混凝改善PAC-UF工艺对有机物去除效率和膜污染效能的影响及机理。结果表明,在线混凝和PAC对去除不同相对分子质量的有机物上存在协同互补作用,当PAC投加量仅为20 mg/L时,在线混凝+PACUF工艺的UV_(254)和DOC去除率为93.6%和69.7%。在线混凝和PAC对原水中亲水性有机物的去除效果较差,去除率小于40%,但是亲水性有机物组分的存在对膜污染的影响几乎可以忽略。当PAC投加仅为20 mg/L时,过滤周期末端膜比通量为0.86。在线混凝可以有效的改善PAC-UF工艺的有机物去除效果和膜污染程度,并可以显著的减低投炭量,利于实际工程运行。 The effects of PAC-UF and PAC-UF treatment on the relative molecular mass distribution, hydrophilicity and hydrophobicity of organic matter in UF influent were investigated by on-line coagulation and powdered activated carbon (PAC) treatment. The effects of PAC-UF process on organic removal efficiency And membrane fouling efficiency and mechanism. The results show that there is synergism between online coagulation and PAC on the removal of organic compounds with different relative molecular weights. When PAC dosage is only 20 mg / L, the UV 254 and DOC removal rates of online coagulation + PACUF process 93.6% and 69.7%. On-line coagulation and PAC removal of raw water hydrophilic organic less effective, removal rate less than 40%, but the presence of hydrophilic organic components on the membrane pollution is almost negligible. When the PAC dosage was only 20 mg / L, the filtration membrane flux at the end of the membrane was 0.86. On-line coagulation can effectively improve the removal efficiency of organics and membrane fouling of PAC-UF process, and can significantly reduce the amount of carbon input, which is conducive to the actual project operation.