电絮凝法深度处理制革废水的实验研究

Advanced Treatment of Tannery Wastewater through Electrocoagulation

采用电絮凝方法深度处理山东某制革厂二沉池出水中的难降解有机物和重金属铬,研究了反应电压、pH、反应时间、电流密度对COD去除效率的影响.实验过程中还计算了阳极消耗量,评估电絮凝反应的经济可行性,并研究了铬的去向.结果表明:实验选用铝钛阳极处理制革废水,反应电压2 V、pH 6、反应30 min、电流密度为800 A/m2时,COD去除率可以达到83.4%,总铬去除率可以达到98.9%,Cr(Ⅵ)去除率达到89.1%,满足制革行业一级排放标准(GB 30486—2013).这表明电絮凝技术可以去除化学沉淀法无法去除的铬组分.

Refractory organics and heavy metal chromium from the effluent of secondary sedimentation tank in a Shandong tannery were treated by using electrocoagulation method.The effects of reaction voltage,pH,reaction time and current density on the COD removal efficiency were studied.In the process of the experiment,the consumption of anode was calculated,the economic feasibility of the electrocoagulation evaluated,and the direction of chromium studied.The results showed that,using aluminum and titanium anode to treat tannery wastewater,when the reaction voltage was 2 V,pH 6,reaction time 30 min,and current density 800 A/m2,the removal efficiency of COD could reach 83.4%,and the total Cr and Cr(VI)removal could reach 98.9%and 89.1%,respectively,which could meet the first level emission standards of leather industry(GB 30486-2013).It was proved that the technology of electrocoagulation could remove the chromium components that could not be removed by chemical precipitation.