| This test takes Luan River water as raw water, going on a year. In this test two membranes which are out-inside membrane and in-outside were compared. The condition in which the two membranes can run stably was discussed. In the period of high temperature and high algae and the period of low temperature and low turbidity a pertinence experiment was carried out upon in-outside membrane. Furthermore, the water quality of effluent from the traditional treatment process and that from Coagulation-Ultrafiltration process were compared.The optimal pretreatment conditions of the two membranes were investigated firstly, and found that coagulation could mitigate the increase trend of trans-membrane pressure, Because coagulation could change the electric charge of granules and weaken the strength between granules and the strength between granules and membrane. In this way, pollutant layer could be washed away easily with reverse-flushing (RF). The coagulation conditions were investigated, and found the increase trend of trans-membrane pressure was slow for in-outside membrane while the dose of FeCl3 changed between 2 mg/L and 4 mg/L and the agglutination reaction timed 7.5min. Polymeric aluminium chloride was used for out-inside membrane. The dose was 8 mg/L and the agglutination reaction time was 15min.In the experiment aimed at confirming the operation parameters, results showed that the optimal run condition of in-outside membrane is that the flux was fixed at 4t/h (2 modules) and the duration at 20min during filtrating, and the duration of both upflow-RF and downflow-RF was fixed at 30s, and the flux of RF at 14t/h, and before RF there were 10s when dope is discharged. Out-inside membrane has the same flux and the duration during filtrating, but the flux and the duration of upflow-RF were 1.2t/h and 40s, downflow-RF 6t/h and 20s. Out-inside membrane exceled in-outside membrane in the reclaim rate, but out-inside membrane's resistibility is weak. Furthermore, the equipment of out-inside membrane is complicated due to appending a fan for RF.The water quality of filtrate from Coagulation-Ultrafiltration process is good. The turbidity of filtrate from in-outside membrane is low than 0.1NTU, and the turbidity has little relation with pretreatment conditions. When the membrane was integrated, the amount of granules that larger than 2μm in filtrate was less than 1 per milliliter, and the removal rate of CODMn was abover than 50%, which was decided by pretreatment conditions. The water quality of the filtrate from Out-inside membrane is worse than that from in-outside membrane. The amount of granules that larger than 2μm in filtrate are between 10 and 20 per milliliter. The removal rate of CODMn is about 50%, but the turbidity is close. The removal rate of organics increases with the content of organics in raw water improving.In the period of high temperature and high algae, for in-outside membrane the removal rate of organics increases with prechloridizing, adding active carbon, improving dose of coagulation, ect. Especially, prechloridizing can improve the removal rate of organics, and also release the membrane fouling. The role of active carbon in releasing the membrane fouling needs farther research. In the period of low temperature and turbidity, cross-flow filtration is the only effective one among all the methods used for keeping steady run. The only method for debasing the pressure is reducing the flux.Compared with the traditional treatment process, the filtrate of membrane has lower turbidity, organics, chloride and iron, but close for other physical parameters. Membrane process and the traditional treatment process are close for removing coliform and bacteria without disinfection, but membrane process is worse in removing atypical coliform, so a small quantity of disinfector is necessary.
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