硫铁化合物还原法处理电镀废水中Cr(Ⅵ)  

Removal of Cr(Ⅵ) from Electroplating Wastewater by Sulfur and Iron Compound

作　　者：韩奎 

机构地区：[1]中铁十九局集团第三工程有限公司,辽宁沈阳110136

出　　处：《沈阳化工大学学报》2016年第1期6-10,22,共6页Journal of Shenyang University of Chemical Technology

基　　金：国家十二五科技支撑计划项目(2014BAJ01B04)

摘　　要：以硫铁矿和硫化亚铁为还原剂，采用还原法处理模拟电镀废水，用以将废水中cr（Ⅵ）转变为cr（Ⅲ），并与水分离．实验结果表明：硫化亚铁和硫铁矿均可作为还原剂还原电镀废水中Cr（Ⅵ），硫化亚铁还原效果好于硫铁矿．水的pH值、还原剂投量及粒径、还原反应时间均影响还原效果．酸性条件下有利于还原反应的进行．经过还原处理后，废水中Cr（Ⅵ）质量浓度达到低于0．2mg／L的排放标准，但是总铬浓度则需要投加混凝剂，经过混合、絮凝、沉淀过程，总铬的质量浓度达到低于1mg／L的排放标准．对于实验用的水质，Cr（Ⅵ）质量浓度约66mg／L，其较佳处理条件：初始pH为3～4，硫化亚铁投量10g/L，粒径0．15～0．18mm，还原反应时间35min，振荡强度160r／min．混凝沉淀时pH为8，聚合氯化铝投量50mg／L，160r／min振荡混合1min，再60r／min振荡絮凝20～25min，沉淀90min．The pyrite and ferrous sulfide reagent were used for reduction treatment of simulated electro- plating wastewater in which,the chromium（ VI ） ion was contained, and the ion was converted to chromi- um（ 11I ）. The chromium in the wastewater was separated from the waste water. The results were shown that both ferrous sulfide and pyrite were used as chromium （VI） reducing agent in electroplating wastewater. The ferrous sulfide was better than pyrite in reduction. The process parameters were investiga- ted, such as pH, the dosage of reducing agent and its particle size, the reaction time. Under acidic condi- tions the process had done. With the reduction reaction the chromium （ VI ） concentration was reduced to 0. 2 rag/L, but the total chromium concentration was lower than 1 mg/L after adding coagulant, mixing, flocculation, and precipitation. For reduction treatment initial pH was 3 -4, and dosage of ferrous sulfide 10 g/L with its particle 0. 15 -0. 18 mm,reducing time 35 rain, shock velocity 160 r/min. The total chro- mium concentration separated from water, when pH was 8, dosage of polyaluminium chloride 50 mg/L, shocking for 1 min with 160 r/min, then flocculation from 20 to 25 min with 60 r/min and precipitation for 90 min.

关 键 词：电镀废水 硫铁化合物 铬 

分 类 号：X703[环境科学与工程—环境工程]