生活垃圾焚烧飞灰中Zn、Pb、Cu的浸出特性

测定了飞灰中Zn、Pb、Cu的浸出毒性及浸出率与pH值的关系,并利用MINTEQA2模型对它们的浸出率以及不同pH值下的主要存在形态进行了模拟。结果表明:Pb、Cu、Zn的模拟浸出值与实测浸出值基本相符,模拟浸出值可反映实际浸出情况;pH值在8~12之间时Zn、Cu、Pb的浸出率接近0;pH<7.5时,Zn的浸出率高达70%~80%,pH值>12时,随着pH值的增加,Pb与Zn的浸出能力逐渐增强;pH<2时,Zn、Cu、Pb的浸出率较大,表明三种重金属在强酸条件下容易浸出。了解重金属在不同pH值下的浸出情况可以帮助预测各种环境中重金属的潜在危害性,并可通过改变环境pH值控制重金属的浸出。

Leaching Behavior of Zn,Pb and Cu from MSWI Fly Ash

The relation ship between pH and leaching behavior of Zn,Pb and Cu is analyzed,based on their leaching ratios at different pH value derived from measurement and MINTEQA2 modeling.It is found that detected leaching ratios of heavy metals conform to those derived from MINTEQA2 modeling.Leaching ratios of Pb,Cu and Zn are close to zero when pH value is between 8 and 12.Leaching ratios of Zn registers between 70% and 80% when pH value is lower than 7.5,and leaching ratios of Pb and Zn increases with the increas...