铁系/石灰-水泥对砷污染土壤稳定化研究

Study on Stabilization of Arsenic Contaminated Soil by Iron System/Lime-Cement

为研究硫酸铁+石灰和硫酸铁+水泥对砷污染土壤固化稳定化效果及机理,作者采集某砷污染场地土壤,模拟工程修复实践使用2组药剂对砷污染土壤进行小试试验,评估了2组药剂对砷污染土壤的固化稳定化效率,探讨了2组药剂对砷固化稳定化机理,并对比分析了2组药剂的修复效果。结果表明,2组药剂对砷固化稳定化都具有显著效果,是砷固化稳定化的经济、高效材料。硫酸铁+石灰对砷的固化稳定化效果在吸附、沉淀和增加pH活化砷的共同作用下,呈非线性特征,并非添加量越高固化稳定化效果越好。硫酸铁+水泥对砷的固化稳定化效果在吸附、沉淀和物理包裹的共同作用下,在一定范围内,添加量的越高固化稳定化效果越好。因此,在不同添加量下,2组药剂对砷固化稳定化效果相比较存在差异,在工程实践中需通过试验确定最经济有效的药剂组合和配比。

In order to study the stabilization effect and mechanism of arsenic-contaminated soil solidified by ferric sulfate+lime and ferric sulfate+cement,soil samples from an arsenic-contaminated site were collected,and two groups of reagents were used to carry out a pilot test on arsenic-contaminated soil in simulated engineering remediation practice.The stabilization efficiency of two groups of reagents for arsenic-contaminated soil was evaluated,and the mechanism of arsenic-solidified stabilization by two groups Repair effect of group A.The results show that the two groups of agents have significant effects on arsenic solidification and stabilization,and they are economical and efficient materials for arsenic solidification and stabilization.The curing and stabilizing effect of ferric sulfate and lime on arsenic is non-linear under the combined action of adsorption,precipitation and increasing p H activated arsenic.It is not that the higher the dosage of ferric sulfate and lime,the better the curing and stabilizing effect.The solidification and stabilization effect of ferric sulfate+cement on arsenic is affected by adsorption,precipitation and physical encapsulation.Within a certain range,the higher the addition,the better the solidification and stabilization effect.Therefore,under different dosage,the two groups of agents have different effects on arsenic solidification and stabilization.In engineering practice,it is necessary to determine the most economical and effective combination and proportion of agents through experiments.