Using sodium bisulfite, sodium sulfite and sodium metabisulfite as reducing agent respectively, reduction effects of the reducing agents on Cr( VI) in electroplating wastewater had been studied under different conditions. Affects of pH, dosage of the reducing agents and reaction time upon the treatment effect were also investigated,finally the optimal reaction condition and the best reducing agent were determined. The best reducing agent was sodium metabisulfite and its best dosage was 1.418g/L. The best reaction time was 2min. and the best precipitation time was 30min.%分别以亚硫酸氢钠、亚硫酸钠及焦亚硫酸钠为还原剂,在不同的条件下对电镀废水中Cr(Ⅵ)的还原效果进行了研究.考察了pH,还原剂、还原反应时间及工业成本对含铬废水处理的影响,最终确定了最佳反应条件.焦亚硫酸钠投加质量浓度为理论量的1.25倍,即1.418 g/L,反应t为2min,效果最好.为了不增加后续反应中产生的污泥量,选择以氢氧化钠作为沉淀反应的中和药剂,确定出中和沉淀反应t为30 min.
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