混凝-Fenton法对中晚期垃圾渗滤液预处理研究

Research on Mature Landfill Leachate Pretreated by Coagulation-Fenton Process

利用混凝-Fenton法对中晚期垃圾渗滤液进行预处理研究。首先以PAC为混凝剂,PAM为助凝剂对垃圾渗滤液进行混凝处理,然后对混凝后渗滤液进行Fenton氧化。考察混凝剂用量,起始pH值,H2O2/FeSO4·7H2O投加比,Fenton试剂投药量和搅拌速度对垃圾渗滤液COD去除的影响,并进行正交试验分析。结果表明:混凝法的最佳投药量为1 L渗滤液投加1.5 g PAC和5 mg PAM;Fenton法的最佳条件为:起始pH值为3,H2O2/FeSO4·7H2O投加比为8∶1,Fenton试剂投药量为135 g/L,搅拌速度为150 r/min;各因素对Fenton试验影响大小为:起始pH值>Fenton试剂投药量>搅拌速度。在最佳条件下,混凝-Fenton法对垃圾渗滤液COD去除率可达91.41%。

Mature landfill leaehate was pretreated by coagulation -Fenton process. Firstly, landfill leachate was treated by coagulation process, using PAC as floeeulant, PAM as coagulant, then landfill leachate treated by coagulation was treated by Fenton process. The effects of operating conditions such as coagulant dosage, initial pH, radio of H2O2/FeSO4·7H2O, Feuton reagent concentration and stirring speed on COD removal were investigated by the single -factor experiment and orthogonal experiment. The experimental result indicated that the optimal conditions found were PAC concentration of 1.5 g/L and PAM concentration of 5 mg/L, initial pH value of 3, radio of H2O2/FeSO4·7H2O of 8, Fenton reagent concentration of 135 g/L, and stirring speed of 150 r/min. The influence order of the Fenton experimental results was initial pH 〉 Fenton reagent concentration 〉 stirring speed. Under the optimum conditions, the COD removal rate of landfill leaehate by coagulation- Fenton process can reach 91.41%.