气化炉渣的重金属浸出特性及化学形态分析

分别采用硫酸硝酸法、水平振荡法和醋酸缓冲溶液法制取气化炉渣的浸出液，考察了不同提取方式对浸出液中重金属质量浓度的影响。采用改进BCR连续提取法对气化炉渣中的重金属Cr，Zn，Cu，Pb，Ni，As，Cd的化学形态进行了分析。实验结果表明：煤气化工艺中的气化炉渣属第Ⅰ类一般工业固体废物;在3种提取方式中，醋酸缓冲溶液法的重金属浸出种类最多，且浸出量最大;Cd和Cr对环境具有较高的潜在危害性，Cu次之，Zn，Pb，Ni，As主要以残渣态形式存在，对环境的直接危害性较低。

Analysis on Leaching Characteristics and Chemical Speciation of Heavy Metals in Gasification Slag

Gasification slag was treated by sulfuric and nitric acid method, horizontal oscillation method and acetate buffer solution method respectively. The effects of different leaching methods on the mass concentration of heavy metals in the leaching solution were studied. And the chemical speciations of heavy metals in the gasification slag,such as Cr,Zn,Cu,Pb,Ni,As and Cd,were analyzed using BCR sequential extraction process. The experimental results show that：The slag of coal gasification is the first class of common industrial solid wastes;The species and quantities of heavy metals leached by acetate buffer solution method are the most;Cd and Cr have higher potential harmfulness to environment, followed by Cu. Zn,Pb,Ni and As are mainly in residual slag forms,and have lower direct harmfulness to environment.