还原性硫酸盐处理电镀废水中Cr^(6+)的试验

Experiment of Hexavalent Chromium(Cr^(6+)) Removal from Electroplating Wastewater by Reductive Sulfates

针对某单位实际生产中的电镀废水(Cr^(6+)质量浓度为1.5 g/L、pH值为2.1),研究了三种不同的还原剂(亚硫酸钠、亚硫酸氢钠、焦亚硫酸钠)对该废水中Cr^(6+)还原去除的最佳投加量,分别为6.0、4.5 g/L和4.2 g/L。还原处理后pH较低,需调节pH值至7.0左右形成沉淀去除。试验表明,采用焦亚硫酸钠做还原剂,代替原工艺中的亚硫酸氢钠,在一定程度上降低了处理成本。

This paper introduces three different kinds of reductant （sodium sulfite, sodium bisulfite, sodium metabisulfite） for the practical electroplating wastewater treatment （ hexavalent chromium concentration is 1.5 g/L , pH value is 2.1 ） . The best dosage is 6.0 , 4.5 g/L and 4.2 g/L respectively. The pH values are low after the reduction treatment, and need to be adjusted to 7.0 to form precipitate. Experiments show that sodium metabisulfite can be the reductant replacing sodium bisulfite in original process, to a certain extent, which reduces the cost of the treatment.