城市中水回用中膜污染分析及对策

Analysis and strategy of membrane fouling in recycling utilization of urban reclaimed water

某火力发电厂在将城市中水回用的过程中,其补给水处理系统中的超滤膜、反渗透膜出现有机物、微生物和无机盐垢组合式污染。通过对预处理水质进行分析和对现场运行设备进行检查,发现预处理杀菌效果不佳、石灰投加量不合理、澄清池后加酸量不足是造成膜污染的主要原因,并据此提出了增设曝气生物滤池、调整软化混凝条件、维护超滤水箱和防止反渗透结垢的具体改进措施。

In the process of reusing urban reclaimed water in a thermal power plant,the ultrafiltration membrane and reverse osmosis membrane in the make-up water treatment system were polluted by organic matter,microorganism and inorganic salt scale.Through the analysis of pretreatment water quality and inspection of field operation equipment,it was found that the main causes of membrane pollution were poor sterilization effect of pretreatment,unreasonable lime dosage and insufficient acid addition after clarifier.Based on these,specific improvement measures were proposed,including adding biological aerated filter,adjusting soft coagulation conditions,maintaining ultrafiltration water tank and preventing reverse osmosis scaling.