连续电镀锡钝化六价铬废水的处理

介绍了连续电镀锡钝化废水处理的还原剂、中和用碱、絮凝剂、助凝剂的选用。检测还原单元的六价铬符合达标排放要求后,令三价铬形成大颗粒的氢氧化物沉淀,通过格栅板实现沉淀分离,上层清液达标排放。经实验室验证后,对原废水处理线进行适当改造,减少了铬泥的产生,降低了废水处理成本。

Treatment of hexavalent chromium-containing wastewater discharged from passivation phase in continuous tin electroplating process

The selection of reductant,alkaline neutralizer,flocculant,and coagulant for treating the wastewater discharged from the passivation phase in a continuous tin electroplating process was introduced.The trivalent chromium ions produced in reduction phase were precipitated as large-sized hydroxide particles when the residual hexavalent chromium reached the emission limit.The precipitates were then separated out through the grid plate,and the supernatant being compliant with the national emission standard was discharged.Through the laboratory verification,the original wastewater treatment process was improved,reducing the production of chromium-containing sludge and the cost of wastewater treatment.