超滤膜在大型供水系统的应用分析与建议

Application of Ultrafiltration Technology in Large-scale Waterworks and Its Suggestion

北方大型供水厂A的处理规模为50×10^(4)m^(3)/d,水厂B的处理规模为8×10^(4)m^(3)/d,均采用压力式超滤膜深度处理工艺。通过分析两水厂的处理效果,发现在超滤工艺运行过程中,当前序工艺采用铁盐混凝剂时,应注意其可能造成膜孔堵塞;当采用铝盐混凝剂时,超滤膜对溶解铝无拦截作用,应注意铝盐投量与出厂水溶解铝浓度。高藻季节应注意藻类和细菌在膜壳内滋生问题。此外,当采用次氯酸钠控制膜污染时,应精准控制出厂水余氯,使出厂水pH稳定,避免由于pH波动对管网水质造成的影响。

Both A waterworks with scale of 50×10^(4)m^(3)/d and B waterworks with scale of 8×10^(4)m^(3)/d in North China adopt the advanced treatment process of pressurized ultrafiltration.Based on the analysis of the treatment performances of two waterworks,attention should be paid to the blockage of membrane pores in the operation of ultrafiltration process when iron salt coagulant was used in the preceding process.When the coagulant was aluminum salt,the ultrafiltration had no intercepting effect on dissolved aluminum,and attention should be paid to the dosage of aluminum salt and the concentration of dissolved aluminum in effluent.For seasonal algae-laden raw water,attention should also be paid to algae and bacteria growth in the membrane shell.In addition,when sodium hypochlorite was used to control membrane fouling,the residual chlorine in effluent should be accurately controlled to stabilize the effluent pH and avoid the impact of pH fluctuations on the water quality of the pipe network.