不同改良剂对镉铅污染土壤修复效果研究

Effect of Combined Amendments on Restoration of Cadmium-lead Contaminated Soil

为研究不同改良剂对重金属复合污染土壤的修复效果,采用室内土壤培养方法,以Cd-Pb复合污染农田土壤为研究对象,探讨3种组合改良剂(羟基磷灰石+沸石、羟基磷灰石+硅藻土、羟基磷灰石+活性炭)在不同施用量条件下(0,0. 5%,1. 0%,2. 5%,5. 0%和10. 0%),对Cd和Pb污染土壤的修复效果。结果表明:三种组合改良剂均能有效提高土壤p H,羟基磷灰石+沸石组合对土壤Cd和Pb固化效果最好,其Ca Cl2提取态和TCLP提取态含量降低55. 4%～67. 1%;而且随着固化剂用量的增加固化效果也逐渐提高。

In order to clarify the effect of different amendments on the restoration of soil Cd and Pb, three kinds of combined amendments such as hydroxyapatite＋zeolite, hydroxyapatite＋diatomite and hydroxyapatite＋biochar were researched through indoor soil culture experiments. There were six application rates for amendments （0, 0.5%, 1.0%, 2.5%, 5.0% and 10.0% ）. The main results of the experiments were as follows： three kinds of combined amendments can all effectively increase soil pH. The combination of hydroxyapatite and zeolite had the best restoration effect on soil Cd and Pb. The extraction content of CaCl 2 and TCLP was decreased by 55.4%~67.1%. With the increment of the amount of combined amendments, the effect of restoration also increased gradually.