双氧水-絮凝法处理含镍、铬的酸洗废水试验研究

Experimental Research on Removing Nickel and Chromium from Acid Pickling Wastewater by H_2O_2-Flocculation

以聚合硫酸铁、聚合氯化铝、聚丙烯酰胺为絮凝剂,采用双氧水-絮凝法对酸洗废水中的镍、铬的去除效果及作用机理进行了研究。实验结果表明,经不同絮凝剂处理后,酸洗废水中镍的去除率为87%~97%,铬的去除率为83%~95%,各种絮凝剂对镍、铬的去除率相差不是很大;与各单体絮凝剂相比,由聚合硫酸铁、聚合氯化铝和聚丙烯酰胺组成的复合絮凝剂净化效率高、絮凝效果好、滤液澄清度大,形成絮体状况佳,沉淀速度快;经不同絮凝剂处理后的酸洗废水对镍均有较高的回收率,在79.3%~91.1%之间;处理后清液中铬含量达一级排放标准。

Using polyferric sulphate,polyaluminum chlorid and polyacrylamide as flocculants,the removal effect and mechanism of nickel and chromium in acid pickling wastewater are studied in this paper by adopting H2O2-flocculation process.Experimental results show that the removal rates of nickel and chromium in wastewater are 87～97% and 83～95% respectively after treated with different flocculants.The difference of removal rate about nickel and chromium among different flocculants is not big.Compared with each single flocculant,the multiple flocculant,which is composed of polyferric sulphate,polyaluminum chlorid and polyacrylamide,has higher purification efficiency and better flocculation effect.Thus,it can obtain clearer filtrate,optimal flocculation status,and rapid precipitation speed.The recovery rates of nickel in acid pickling wastewater treated with different flocculants are relatively higher（from 79.3% to 91.1%）.Concentration of chromium in filtrate is up to the state＇s effluent standard of first-class.