Cu_2O处理黄金冶炼酸性废水中Cl^-的试验研究

Experimental Study on Treatment of Chloride Ion in Gold Smelting Acid Wastewater by Cuprous Oxide

黄金冶炼企业产生的酸性废水一般采用石灰中和法处理后返回系统使用,但该方法的缺点是无法去除废水中的Cl^-。为消除Cl^-不断沉积带来的危害,针对冶炼酸性废水开展了试验研究。通常Cl^-的去除原理是利用其他阴离子替换Cl^-,或者将Cl^-与其他阳离子一并去除。利用Cu_2O作为沉淀剂,与Cl^-共同沉淀,以达到去除Cl^-的目的。为确定最佳试验条件,考察了在不同pH值、温度和Cu_2O用量情况下Cl^-的去除效果。试验结果表明:在室温条件下,当溶液pH值为0.5,Cu_2O用量为10 mg/L,反应时间为20 min时,可获得Cl^-去除率达95%以上的良好效果。结果证明,利用Cu_2O能够有效去除黄金冶炼酸性废水中的Cl^-,且生成的Cu_2O沉淀在酸性废水中稳定存在,易于过滤去除。在实际生产工艺中,Cu_2O也实现了循环除氯,节约了生产成本,为同类型企业去除酸性废水中Cl^-提供了参考。

The acidic wastewater generated by gold smelting enterprise is generally treated by the lime neutralization method and returned to the system,but the disadvantage of this method is that the chloride ions in the wastewater can not be removed.In order to eliminate the harm caused by the continuous deposition of chloride ions,an experimental study was carried out on smelting acidic wastewater.Usually,the principle of chloride ion removal is to replace chloride ions with other anions or remove chloride ions together with other cations.Cuprous oxide was used as precipitant and precipitatedwith chloride ion,so that to achieve the purpose of removal.In the experiment,in order to determine the best experimental conditions,the chloride ion is investigated under different pH,temperature and cuprous oxide dosage.The removal effect is measured by the chloride removal rate.Finally,the good experimental results of chlorine removal rate above 95%can be obtained under the condition that the pH value of the solution is 0.5,the amount of cuprous oxide is 10 mg/L,and the reaction rate is 20 min at room temperature.The results show that the use of cuprous oxide can effectively remove the chloride ions in the acid smelting acid waste water,and the formed cuprous chloride precipitate is stable in acidicwastewater and easy to be filtered and removed.In the actual production process,cuprous oxide also can circulating dechlorination,which saves production cost and provides a data reference to remove chloride ions fromacidic for the same type of companies.