响应面法优化电芬顿预处理焦化废水研究

Optimization of Electro-Fenton Process as a Pretreatment for Coking Wastewater using Response Surface Methodology

为了探究电芬顿(electro-Fenton)技术对焦化厂蒸氨废水的处理效果,考察反应时间、初始pH值和电流密度对废水COD去除效率的影响;利用Box-Behnken实验设计(BBD)与响应面方法(RSM)设计和优化电芬顿工艺参数,建立了焦化废水COD去除率的二次回归模型,并通过方差分析(ANOVA)验证了该模型的准确性,得出反应过程参数的线性作用与交互作用的显著性水平。RSM结果表明:最佳工艺条件下,反应时间2h,废水pH值2.62,电流密度3.17mA/cm2,COD的去除率为70.02%,废水B∶C比值由0.12提高至0.41。电芬顿技术可以有效去除和转化蒸氨废水中的难降解有机物,从而提高焦化废水的可生化性,适用于焦化废水原水的预处理。

In order to explore the treatment effect of distilled ammonia wastewater of coking plant,the Electro-Fenton process was employed.The effects of reaction time,initial pH value and electric current density on COD removal efficiency were investigated.The Box-Behnken experimental design（BBD）and response surface methodology（RSM）were used to design and optimize the performance of electro-Fenton process.The regression quadratic model describing COD removal efficiency of electro-Fenton process was developed and validated by the analysis of variances（ANOVA）.The significance levels of linear and interaction effects of the reaction parameters on processes efficiencies were obtained.The results show that the highest COD removal efficiency of 70.02%and the value of B∶C from 0.12 to 0.41 were achieved at 2hof reaction time,pH 2.26 and 3.17mA/cm^2 of current density.The electro-Fenton technology can effectively degrade refractory organics and improve biodegradability of coking wastewater,which is suitable for the pretreatment process of coking wastewater.