废铁屑-改性粉煤灰联用处理铬渣渗滤液

针对铬渣严重污染环境问题,以"以废治废"为研究目标,采用室内静态实验方法,进行废铁屑-改性粉煤灰联用处理铬渣渗滤液中Cr(Ⅵ)和总铬实验研究。实验结果表明,废铁屑与聚合氯化铝改性粉煤灰联用处理Cr(Ⅵ)和总铬效果优于单独采用其中一种物质;处理Cr(Ⅵ)浓度208 mg/L、总铬浓度260 mg/L的200 mL高浓度含铬废水最佳反应条件为:反应时间30 min,总投加量40 g,配比为1:1, pH值4.1,对应Cr(Ⅵ)去除率99.93%,总铬去除率99.72%。处理后水质满足《污水综合排放标准》(GB 8978-1996)要求。

Treatment of chromite ore processing residue leachate by scrap iron combined with modified fly ash

Aiming to solve the problem of severe environmental pollution caused by chromite ore processing residue(COPR), taking "using waste to treat waste" as the research objective, hexavalent chromium and total chromium from COPR leachate were treated by scrap iron combined with modified fly ash through an indoor static test. The experimental results show that combining scrap iron with modified fly ash using polyaluminum chloride for the removal of hexavalent chromium and total chromium had advantages when compared to the single scrap iron or modified fly ash methods. The optimal operating parameters for chromium removal from 200 mL of wastewater with concentrations of hexavalent chromium of 208 mg/L and total chromium of 260 mg/L were as follows: reaction time of 30 minutes, total dosage of 40 g, mass ratio of scrap iron to modified fly ash of 1:1, and pH of 4.1. Under these conditions, the removal rates for hexavalent chromium and total chromium were 99.93% and 99.72%, respectively. The water quality after treatment met the Integrated Wastewater Discharge Standard(GB 8978-1996).