摘要
通过复合固化/稳定化药剂对镍污染土壤进行固化/稳定化处理,并采用镍浸出浓度、镍形态分析和生物活性指标综合评价其固化/稳定化效果。结果表明,相对于对照组,采用腐殖酸钠+普通硅酸盐水泥、磷酸二氢铵+普通硅酸盐水泥处理镍污染土壤,镍浸出浓度和生物活性均显著降低,但随着药剂量增加以及养护周期延长,所有试验组的镍浸出浓度和生物活性呈小幅度下降趋势;所有试验组的可交换态占比大幅度降低,碳酸盐结合态占比小幅度降低,而铁锰结合态、有机态和残渣态占比均有小幅度增加,但随着药剂添加量和养护周期增加,可交换态和碳酸盐结合态占比呈小幅度下降趋势,而铁锰结合态、有机态和残渣态占比呈小幅度增加趋势,并趋于稳定;腐殖酸钠+普通硅酸盐水泥的处理效果均优于磷酸二氢铵+普通硅酸盐水泥,腐殖酸钠+普通硅酸盐水泥可作为镍污染土壤修复的固化/稳定化药剂。
The nickel-contaminated soils were solidified/stabilized by using compound solidification/stabilization agents,and the effects of solidification/stabilization were evaluated by using the index of nickel leaching concentration,nickel speciation analysis and bioactivity.The results showed that,compared with the CK group,nickel contaminated soils were treated with humic acid+common portland cement and ammonium dihydrogen phosphate+common portland cement,the leaching concentration and bioactivity of nickel were significantly decreased,but with the increase of dosage and the extension of curing period,the leaching concentration and bioactivity of nickel were showed a slight downward trend in all experimental groups;the proportion of exchangeable state decreased significantly in all experimental groups,the proportion of carbonate bound state decreased slightly,while the proportion of Fe-Mn bound state,organic state and residual state increased slightly,but with the increase of dosage of reagent and curing period,the proportion of exchangeable state and carbonate bound state decreased slightly,the proportion of Fe-Mn,organic and residual states increased slightly and tended to be stable;the treatment effect of humic acid+common portland cement was better than that of ammonium dihydrogen phosphate+common portland cement,and humic acid+common portland cement could be used as solidification/stabilization agents for remediation of nickel-contaminated soil.
出处
《环境保护与循环经济》
2022年第9期48-53,共6页
environmental protection and circular economy
关键词
镍污染土壤
固化/稳定化
浸出浓度
形态分布
生物活性
nickel contaminated soil
solidification/stabilization
leaching concentration
morphological distribution
bioactivity
