摘要：

印刷线路板含铜蚀刻废液经电解回收铜后,残留硫酸根质量浓度仍高达72 g/L,盐度极高,难以后续生物处理。采用优化三步沉淀技术,溶液中硫酸根质量浓度下降到4.1 g/L,硫酸根回收率为94.33%。然后用NaOH直接沉淀Cu²⁺,溶液中Cu²⁺从748 mg/L下降至4 mg/L,铜的回收率高达99.37%。该技术既去除了废水中大部分的盐分离子,又回收了硫酸根和铜,为后续生化处理奠定了良好的基础。

关键词: 含铜蚀刻废液, 高盐度, 优化三步沉淀技术, 达标排放

Abstract:

After the copper etching solution on the printed wiring board has been recovered by electrolysis,the concentration of residual sulfate radical is still as high as 72 g/L,and its salinity is very high. Therefore,it is difficult to do the subsequent biological treatment. The sulfate radical concentration can directly be reduced to 4.l g/L and the recovery rate of sulfate radical is 94.33%,by the optimized three-step precipitation technique. Then,Cu²⁺ concentration can directly be reduced from about 748 mg/L to 4 mg/L and the recovery rate of copper is as high as 99.37%,by precipitating copper ions directly with NaOH. This technique can not only remove most of salt ions from wastewater,but also recover sulfate radical and copper ions,laying a good foundation for the subsequent biological treatment.

Key words: copper etching solution, high salinity, optimized three-step precipitation technique, discharge standard

中图分类号: 

• X703.1