应用络合沉淀-化学氧化组合工艺处理高浓度含氰农药废水

Treatment of high-concentration cyanide-containing pesticide wastewater with a combined process of complexation precipitation and chemical oxidation

由于氰化物的剧毒性以及农药废水的难生物降解性,含氰农药废水的治理难度较大。从工程应用的角度出发,在小试实验研究的基础上,确定了处理污染物含量高、难生物降解含氰农药废水的组合工艺流程为:FeSO4络合沉淀→H2O2催化氧化→C lO2深度氧化。组合工艺流程处理效果好,操作方便,出水水质稳定。研究结果表明,当FeSO4加入量为理论计算值的1.3倍、3%H2O2和C lO2投加量分别为24 mL/L和200 mg/L时,废水中CN-离子的总去除率高达99.99%以上,COD总去除率达到99%。组合工艺不仅适用于处理高浓度含氰农药废水,而且也能为高浓度、难降解有机废水的治理提供有益的参考。

It is very difficult to treat high-concentration cyanide-containing pesticide wastewater because of its toxic and refractory nature. An efficient combined process, i. e. , complexation precipitation followed by HEO2 oxidation and ClO2extensive oxidation, was developed in the present study through lab-scale tests to treat the cyanide-containing pesticide wastewater. The experimental results show that the removal rates of CN - and COD were above 99.99% and 99% , respectively. The results of the experiments show that the optimal conditions are： FeSO4 dosage 1.3 times of the theoretical value,3% H2O2 dosage 24 mL/L and C102dosage 200 mg/L. This new process is not only applicable to treating high-concentration cyanide-containing wastewater, but also provides instructive example for efficient treatment of refractory organic wastewater.