铁屑/CO_2体系处理含铬(Ⅵ)废水的研究

Treatment of Chromium(Ⅵ)-containing Wastewater by Iron Scrap /CO_2 System

在铁屑还原废水中Cr(Ⅵ)的过程中,为避免引入Cl-等二次污染物和减缓设备腐蚀,用CO2替代HCl等强酸提供H+,考察对Cr(Ⅵ)的去除效果。结果表明,采用铁屑/CO2体系处理含铬(Ⅵ)废水是可行的,200 mL/min的CO2通入量足以使反应体系的pH值维持在5.2左右,在此条件下,当初始Cr(Ⅵ)浓度为100 mg/L、铁屑投加量为60 g/L、搅拌速度为50 r/min时,反应30 min后对Cr(Ⅵ)的去除率可达到97%。

In order to avoid the introduction of Cl^-- and other secondary pollutants and slow down equipment corrosion, carbon dioxide instead of strong acid （HCl） was used to produce H ＋ during chromium （ VI ） reduction by iron scraps. It was found that the iron scrap/CO2 system was feasible in Cr（ Wl ） removal from wastewater. The flow rate of CO2 at 200 mL/min was sufficient to keep the pH at about 5.2. The Cr（ VI ） removal rate was 97% after 30 min of reaction when initial chromium （ VI ） concentration, iron scrap dosage and stirring rate were 100 mg/L, 60 g/L and 50 r/min respectively.