无机稳定剂处理重金属污染土壤

Treatment of Heavy Metal Contaminated Soil with Inorganic Stabilizer

以重金属污染土壤为研究对象,比较了铁屑、蒙脱石、碳酸钙和羟基磷灰石4种稳定剂对土壤中Pb,Zn,Cd,Cu 4种重金属的稳定效果。实验结果表明,4种稳定剂稳定效率的大小顺序为:羟基磷灰石>碳酸钙>蒙脱石>铁屑。当稳定剂质量分数为10%时,羟基磷灰石、碳酸钙、蒙脱石和铁屑对Pb,Zn,Cd,Cu 4种重金属的平均稳定效率分别为99.63%,98.53%,97.15%,86.95%。未加稳定剂时,土壤中的Pb以残渣态为主,Zn以残渣态和可交换态为主,Cd以残渣态为主,Cu以残渣态和可交换态为主;加入稳定剂后,土壤中4种金属可交换态的所占比例(简称占比)均显著降低,还原态的占比明显增大,残渣态的占比略有增大,氧化态的占比基本保持不变。

Taking heavy metal-contaminated soil as research object,the effects of 4 stabilizers （scrap iron,montmorillonite,calcium carbonate and hydroxyapatite） on the stabilization of Pb,Zn,Cd,Cu in soil were investigated. The experimental results indicate that the stabilization effect order of the 4 stabilizers is hydroxyapatite〉calcium carbonate〉montmorillonite〉scrap iron. When the stabilizer mass fraction is 10%,the average stabilization efficiencies of hydroxyapatite,calcium carbonate,montmorillonite and scrap iron on Pb,Zn,Cd,Cu are 99.63%,98.53%,97.15%,86.95% respectively. In the soil without stabilizer,Pb is mostly in residual state, Zn is mostly in residual and exchangeable state,Cd is mostly in residual state,Cu is mostly in residual and exchangeable state; In the soil with stabilizer,the fractions of exchangeable states of the 4 heavy metals are all significantly decreased,those of reduction states are significantly increased,those of residual states are slightly increased,and those of oxidation states are not changed.