Zn,Cu和Ni污染土壤中重金属的化学固定

利用化学固定剂处理被污泥中Zn,Cu和Ni污染的土壤,研究不同化学药剂对重金属离子的固定技术.结果表明,石灰、硫化物和硅酸盐对Zn都有较好的稳定效果,硫化物对Cu的稳定效果较好,硅酸盐和石灰对Ni的稳定效果较好;对于被Zn,Cu和Ni污染的土壤,混合药剂对重金属污染物的固定效果最佳.研究表明通过调解系统的pH和生成稳定化合物形态使土壤中Zn,Cu和Ni得以固定.通过硫化物 石灰化学固定处理,固定前后Zn,Cu和Ni的不稳定形态含量分别减少了69%,56%和59%.

CHEMICAL STABILIZATION OF HEAVY METALS IN Zn, Cu AND Ni CONTAMINATED SOIL

The experiment was carried on the stabilization technique of heavy metals in the soil contaminated by sludge with chemical methods.The research showed,in three main contented elements Zn,Cu and Ni,the fixing effect of heavy metals contaminated soil were different by using different chemical reagent with different quantity.Lime,silicate and sulfide have higher stabilization ratio to Zn,sulfide with higher stabilization ratio to Cu,lime and silicate with higher stabilization ratio to Ni.For all three of heavy metals,mixture of sulfide and lime have higher stabilization ratio.The result shows that Zn,Cu and Ni in contaminated soil were fixed by adjusting of pH in the system and forming compounds with more stably chemical speciation,And the unsteady specie of heavy metals in contaminated soil is reduced obviously,the unsteady specie of Zn,Cu and Ni reduced 69%,56% and 59% respectively treated by mixture of sulfide and lime.