浅议电镀废水零排放技术的集成与应用

Integration and Application of Zero Discharge Techlonogy for Electroplating Wastewater

电镀行业所产生的废水除了含有铬、镍、铜、镉等重金属,还含有氰化物、磷酸盐等污染物,污染性强。因此,解决电镀废水的污染问题成为该行业发展的关键所在。通过某机械工具厂的实际案例,分析和讨论了电镀废水零排放的技术集成及应用情况。通过将电镀废水进行分质分流并单独进行化学法预处理至达到排放要求,再通过一段RO、二段RO、DTRO等三段浓缩,最后的浓缩液再经过蒸发器蒸发结晶,RO的产水回用于生产线,从而实现废水完全回用不外排,同时运行成本也在可接受范围内,得出电镀废水零排放是可行并可进行推广的结论。

Containing not only heavy metal ions like Cr, Ni, Cu and Cd, but also pollutants like cyanide and phosphate, electroplating wastewater is a strong pollution. So, how to solve the pollution problem of electroplating wastewater is crucial for the development of electroplating industry. The integration and application of zero discharge technology for electroplating wastewater were analyzed and discussed based on the actual case of a machine tools factory. The electroplating wastewater was separated based on quality and treated with a chemical pretreatment separately to meet the discharge requirements, and then concentrated through three stages: the first stage RO, the second stage RO, and third state DTRO. Finally, the concentrated liquid was evaporated and crystallized by the evaporator, and the water produced in RO stage was reused by the production line. Thus the wastewater was completely reused with an accepatble operating cost. It was concluded that a zero discharge of electroplating wastewater was feasible and could be promoted.