Fe^0/GAC-Fenton异相耦合深度处理焦化废水

Advanced treatment of coking wastewater by Fe^0/GAC-Fenton heterogeneous coupling process

采用由Fe0/GAC和H_2O_2构建的微电解与Fenton异相耦合降解体系对焦化废水进行深度处理,通过单因素影响实验和正交优化实验,考察了H_2O_2投加量、进水pH、HRT和mFe0/mGAC对处理效果的影响并确定了最佳反应条件。结果表明:随着各工艺参数取值的增大,系统对有机物的去除效率呈先上升后下降或趋于稳定的趋势;各影响因素的主次顺序为:H_2O_2投加量>进水pH>HRT>mFe0/mGAC,H_2O_2投加量和进水pH为显著性影响因素;当H_2O_2投加量为1.2 m L·L^(-1),进水pH=3,HRT=90 min,mFe0/mGAC=3时,系统处理效果最佳,COD由306 mg·L^(-1)降至94 mg·L^(-1),去除率稳定达到69.2%,满足《炼焦化学工艺污染物排放标准》(GB 16171^(-2)012)对现有企业直接排放的要求。

A heterogeneous and coupling micro-electrolysis Fenton system that uses Fe0/GAC and H_2O_2 was applied in the advanced treatment of coking wastewater. The effects of H_2O_2 dosage,pH,HRT,and mFe0/mGACratio on COD removal efficiency were studied,and the optimum conditions for such were determined,by single factor experiments and an orthogonal test. The results showed that the COD removal efficiency initially increased,and then decreased or remained stable,with increases of each factor. The influence of these factors ranked as follows： H_2O_2 dosage pH HRT mFe0/mGACratio,with H_2O_2 dosage and pH deemed significant. At the optimum conditions of an H_2O_2 dosage of 1. 2 m L·L^-1,influent pH of 3,HRT of 90 minutes,and mFe0/mGACratio of 3,the concentration of COD was reduced from 306 mg·L^-1to 94 mg·L^-1,which is a removal rate of 69. 2%. This final COD concentration meets the direct discharge limit of the Emission Standard of Pollutants for Coking Chemical Industry（ GB 16171-2012） that has been set for existing enterprises.