Study On MF Membrane Treatment For Micro-polluted Water And The Influence Of Iron,Manganese On Membrane Fouling

Now it is necessary to develop efficient and healthy drinking water treatment process due to the pollution of surface water, the limitation of conventional water process and the gradually stringent water quality standard.Membrane technology is regarded as "water treatment technology in the 21^st Century", and has gat more attention of more researchers than before.The Huangpujiang River water source was used as a model sample in this study. The removal effect of hybrid microfiltration membrane process with coagulant and several pre-oxidant respectively, and the factor of affecting flux during membrane filtration were evaluated.Through experiments , the congclusions were attained as follows.1. The results demonstrated that his combined process of the three pre-oxidants and coagulation MF membrane could effectively remove turbidity and Fe respectively, which meet the requirement of Sanitary Standard for Drinking Water Quality . For the removal of organics, ozone pre-oxidation/ coagulation/ MF was the best; sodium hypochlorite pre-oxidation/ coagulation/ MF took the second place and potassium permanganate pre-oxidation/ coagulation/ MF was the worst. When the COD_Mn of raw water was less than 6.5mg/L , the COD_Mn of treated water by ozone pre-oxidation/ coagulation/ MFcombined process was less than 3.0 mg/L, and all the concentration of manganese was less than 1.0mg/L.2. When the raw water quality was very bad ,the treated water quality was improved with the addition of PAC.The experiment demonstrated that the efficiency of COD_Mn was inhanced by PAC with the presence of ozonation and the removal of COD_Mn was inefficient by PAC without ozonation.3. The pilot experiment indicated that manganese has a greater responsibility for increasing of the transmembrane pressure, which was caused by the manganese oxide such as MnO₂ deposited inside the pores.4. The influence of iron and manganese on the membrane flux was tested and the results showed that iorn has a greater responsibility for the decline of the membrane flux.On the based of results of batch test and proposed original concept, it is feasible for ozone pre-oxidation/coagulation/MF combined process to treat micro-polluted water. Besides reducing the influence from organics, it is one of the keys to remove iron and manganese in the pretreatment before membrane ensuring following MFmembrane run with flux for a long time.