亚硫酸氢钠处理电镀废水中铬的实验研究  

Experimental Study on Treatment of Chromium in Electroplating Wastewater by Sodium Bisulfite

作　　者：冯西平[1] 冯婷希 

机构地区：[1]四川化工职业技术学院化学工程系,四川泸州646005

出　　处：《电镀与环保》2018年第1期64-67,共4页Electroplating & Pollution Control

摘　　要：分别以亚硫酸氢钠和亚硫酸钠为还原剂,以氢氧化钠和氢氧化钙为沉淀剂,采用还原沉淀法处理电镀废水中的铬。研究表明:以亚硫酸氢钠为还原剂、以氢氧化钙为沉淀剂时,电镀废水中铬的去除效果最好。采用单因素试验研究了亚硫酸氢钠的用量、还原反应pH值等对废水中Cr(Ⅵ)去除效果的影响。当亚硫酸氢钠用量为理论用量的1.75倍、还原反应pH值为2时,Cr(Ⅵ)的去除率达到99.35%,处理后废水中Cr(Ⅵ)的质量浓度为0.13mg/L。以氢氧化钙为沉淀剂、沉淀反应pH值为8时,处理后废水中总铬的质量浓度为0.26mg/L。在最佳工艺条件下,处理后废水中Cr(Ⅵ)的质量浓度、总铬的质量浓度及出水pH值均满足《电镀污染物排放标准》(GB 21900—2008)中规定的要求。The chromium in electroplating wastewater was removed with sodium bisulfite or sodium sulfite as reducing agent and sodium hydroxide or calcium hydroxide as precipitant by reduction precipitation method. Research showed that the removal efficiency of chromium in electroplating wastewater is the best with sodium bisulfite as reducing agent and calcium hydroxide as precipitant. The effects of sodium bisulfite dosage and reduction reaction pH value on the removal efficiency of Cr（VI） were studied by single factor experiment. Research showed that the removal efficiency of Cr（VI） could be 99.35% under the conditions, sodium bisulfite was 1.75 times the theoretical amount, reduction reaction pH= 2, the mass concentration of Cr（VI） in wastewater was 0. 13 mg/L after treatment. The mass concentration of total chromium in wastewater was 0.26 mg/L under pH= 8 with calcium hydroxide as precipitant after treatment. The mass concentration of Cr（VI）, total chromium and pH value all meet the emission limit requirements in the pollutant emission standard for electroplating （GB 21900--2008） under the optimum technological conditions.

关 键 词：电镀废水 铬 还原沉淀法 去除率 

分 类 号：X781.1[环境科学与工程—环境工程]