[Effect of ozone/coagulation pretreatment on membrane fouling reduction]

In order to investigate the effect of ozone and coagulation pretreatments on organic matter and MF membrane filtration, pretreated Huangpu River surface water was filtrated by MF membrane. The results showed that there were the optimal dosages of ozone and coagulant made maximum membrane flux. The result of membrane fouling reduction by coagulation was better than that by ozone, which was relative to character of organic matter removed by two pretreatment processes. Organics in Huangpu River water mostly concentrates in relative molecule mass (Mr) ranging 3 x 10(3)-5 x 10(3). Research on the chemical cleaning of the fouled membrane indicated that fouling organic substance concentrated about Mr 4.5 x 10(3). Removals of Mr 3 x 10(3) organic matter are higher than Mr 5 x 10(3) organic matter by ozone oxidation. Coagulation process can remove 5 x 10(3) high relative molecular mass organic matter effectively. Removal of these organics fouled membrane by coagulation was better than that by ozone, thereby to effectively reduce membrane fouling.