Abstract:In this study, the PVC alloy ultrafiltration(UF)membrane pilot device and different pretreatment processes were used to develop three processes, including the coagulation-UF, coagulation-sedimentation-UF, and coagulation-flotation-UF processes, for the treatment of slightly-polluted reservoir water. The water purification effects of these processes and the changing pattern of the transmembrane pressure(TMP)were analyzed. The results show that the turbidity removal rate was above 99% when the three processes were used; almost no algae or bacteria were detected in the outflow through microscopic examination; the three processes can be ranked by their effects in removing CODMn and UV254in the following descending order: coagulation-flotation-UF, coagulation-sedimentation-UF, and coagulation-UF; the results of ATR-FTIR show that hydrophilic organic matter was the main substance causing membrane fouling; during the low-temperature and low-turbidity period, the slope of the variation trend line of the TMP was 0. 016 4, and the average TMP was 23. 57 kPa; and, during the high-temperature and algae-laden period, the slope was 0. 043 2, and the average TMP was 21. 28 kPa.