高浓度氰化物废水处理的研究和应用

A Study of Treatment of High-Cyanide-Containing Wastewater and Application Thereof

对某企业的高浓度氰化物废水提出采用沉淀-碱性氯化法解决方案。首先通过补充适量的亚铜离子使高浓度氰化物废水形成氰化亚铜沉淀,过滤后的滤液再用次氯酸钠氧化,废水达标排放,废渣回收利用。试验确定了处理高浓度氰化物废水最佳的操作条件为:当进水水质CN-的质量浓度为71000mg/L时,亚硫酸过量14%,次氯酸钠投加量为废水中总氰的30倍,沉淀反应终点为pH值3.5,出水中CN-的质量浓度不大于0.1mg/L。实际应用证明该方案是切实可行的,不仅安全、简单,而且时间短、费用低。

A precipitation-alkaline chlorination process is proposed as a solution for the treatment of the high-cyanide-containing wastewater from an enterprise. First, proper quantity of cuprous ion is added to make cuprous cyanide to precipitate in the high-cyanide-containing wastewater; then, the filtrate after filtration is oxidized by sodium hypochlorite; the wastewater is discharged after having met the standard for discharge while the sludge is recovered for reuse. The optimal operation conditions for the treatment of the high-cyanide-containing wastewater are determined through tests, that is: when the mass concentration of CN- in influent water is 71 000 mg/L, sulfurous acid excesses 14%, the dosage of sodium hypochlorite is 30 times the total cyanogen in wastewater, the end of the deposition reaction is: the pH value is 3.5, the mass concentration of CN- in effluent water not exceed 0.1 mg/L. This solution has been proved feasible through practical application not only because it is safe and simple but also because the time needed is shorter and the cost is lower.