低碳固化剂修复重金属污染黏土的水动力参数测评

Evalution of hydrodynamic dispersion coefficients of nickel and zinc released from a contaminated clay solidified/stabilized by a low-carbon binder

低碳修复剂研发与修复污染土的安全利用是推行污染场地绿色可持续修复的有效途径。以新型低碳钢渣基固化剂修复重金属镍(Ni)、锌(Zn)污染土为研究对象,通过柱状柔性壁渗透试验,采用溶质浸出质量比法测评了污染土修复前后的土水动力弥散系数。结果表明:固化土样渗透液重金属浓度显著低于污染土样,满足IV类地下水环境质量要求;与污染土相比,固化土的水动力弥散系数降低约2个数量级。研究成果为新型低碳钢渣基固化剂的固化稳定化效果评价及固化土作为土工材料安全性评估提供指导。

A low-carbon by-products-based binder-solidified/stabilized soil was subjected to the flexible wall permeability tests to obtain the hydrodynamic dispersion parameters by periodically measuring the concentrations of nickel and zinc of the effluent.The results demonstrate that the addition of the by-products-based binder decreases the concentrations of nickel and zinc in the effluent liquid.The concentrations of heavy metals are lower than that of the original contaminated soil,and meet the requirements of IV-Grade underground water regulated by China's standard GB/T14848—2017.The hydrodynamic dispersion coefficients of nickel and zinc in the treated soil decrease by 2 order of magnitudes as compared to those of the untreated contaminated soil.