A lot of washing wastewater is produced from surface grinding as well as electroplating of copper, nickel and tin during the production of printed circuit board (PCB). It is significant to recover the wastewater due to its low contamination and large amount. The effluent from chemical treatment of common washing water produced by PCB manufacturing was recovered via a combined ultrafiltrationnanofiltration (UF-NF) process. The removal of CODcr, Cu2+ and TDS (total dissolved solids) and recovery rate in different operation conditions were studied. The results indicated that the removal efficiencies of CODCr, Cu2+ and TDS is up to 91.34％, 98.91％ and 96.72％, respectively; the average water effluence ratio is up to 53.65％ and the treatment cost is 1.68 RMB/t under the conditions of operation pressure 0.8 MPa, water inflow ca.0.7 m3/h and backwashing period 2 h for UF and operation pressure 0.8 MPa, water inflow 1 m3/h, influent pH 6-9, backfiow ratio of concentrated water 0.5 for NF during a cleaning period of 40 d.%印刷线路板生产过程中产生大量的清洗废水,它主要来源于表面研磨清洗和电镀铜、镍、锡清洗等工序,其污染物浓度较低,水量大,回收利用的意义重大.试验采用超滤-纳滤组合工艺回用处理印刷线路板一般清洗废水经化学处理后的出水,研究了不同操作条件下,废水中CODcr、Cu2+和TDS(溶解性总固体)的去除效果及回收率.结果表明,在超滤运行压力为O.2 MPa、进水流量为0.7 m3/h和反冲洗周期为2 h,纳滤膜系统运行压力为0.8 MPa、进水流量1.0m3/h、进水pH为6～9和浓水回流比0.5的条件下,在40 d的清洗周期内,组合工艺对CODcr、Cu2+和TDS的平均去除率分别可达91.34%、98.91%和96.72%,平均产水率可达53.65%,处理成本为1.68元/t.
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