一种含砷废水的处理技术研究

Research on Treatment Technology of Arsenic-Containing Wastewater

摘要: 本文对某半导体企业生产过程中产生的高浓度含砷废水进行安全处理技术研究，通过氧化法对含砷废水进行氧化预处理，处理后通过化学沉淀法加入沉淀剂(钙盐、铁盐)沉淀除砷，并系统研究了氧化剂用量、铁盐用量、反应时间、反应温度、搅拌速率对砷去除效率的影响。研究结果表明：当n(H₂O₂)/n(As)比为1.2/1.0、反应溶液pH为9.0、n(Fe)/n(As)比为1.3/1.0、反应温度为60℃、反应时间为2 h时，处置后的废水砷含量为0.1 mg/L，砷的去除率在99.9%以上。处置后的废水满足《污水综合排放标准》GB 8978-1996中排放指标的要求。

Abstract: In this paper, the safety treatment technology of high-concentration arsenic-containing wastewater produced in the production process of a semiconductor enterprise was studied, and the wastewater was oxidized and pretreated by the oxidation method. After treatment, the arsenic removal was removed by adding precipitating agents (calcium salt and iron salt) by chemical precipitation method, and the effects of the dosage of oxidizer, dosage of iron salt, reaction time, reaction temperature and stirring rate on the removal efficiency of arsenic were systematically studied. The results show that when the ratio of n(H₂O₂)/n(As) was 1.2/1.0, the pH of the reaction solution was 9.0, the ratio of n(Fe)/n(As) was 1.3/1.0, the reaction temperature was 60˚C, and the reaction time was 2 h, the total arsenic concentration in wastewater can be reduced by 0.1 mg/L, and the removal rate of total arsenic in wastewater reaches more than 99.9%. The treated wastewater meets the requirements of discharge index in GB 8978-1996 of the “Comprehensive Sewage Discharge Standard”.