Application of a hybrid process combining ozone- coagulation -microfiltration for drinking water production

The study concerns on drinking water treatment with combining ozonation process, coagulation and Microfiltration (MF) of Poly-vinylidene Fluoride (PVDF) in a dead-end filtration. The pilot-scale process consists of several parts: pre-ozonation, coagulation, sedimentation and microfiltration membrane separation. Ozone of 0.5mg/l and alum of 10 mg/l were added into raw water. The experience focuses on investigation of permeate water quality and variation of trans-membrane pressure (TMP). The results of the study showed that good permeate quality were fulfilled. Turbidity of permeate was consistently below 0.1 NTU. The MF membrane removed iron perfectly, which was below 0.3 mg/l. The reduction of manganese and CODMn, met the China Drinking Water Regulations. Additionally, TMP was stable during filtration for a long time and ozone could delay membrane fouling. Chemical cleaning of membrane could decrease TMP to initial level, and chemical analysis for chemical cleaning solution shown that organic matters and manganese caused membrane fouling.