Through “sulphuric acid -nitric acid”leaching test,using arsenic leaching concentration as the control indicator,stabilization treatment of waste residue containing arsenic using ferrous chloride as stabilization agent is studied.Effects of parameters such as Fe /As molar ratios,pH value,particle size of the waste residue, leaching temperature and treatment time on arsenic leaching concentration are investigated.Migration and transformation of arsenic are discussed by comparing the change of arsenic form before and after stabilizing. Results show that the arsenic leaching concentration might decrease with an increase in FeCl2 dosage.When the molar ratio of Fe /As≥1.0,pH =6.5 ~7.5,and stabilization treatment time ≥60 mins in room temperature,the arsenic leaching concentration is lower than 2.5 mg/L and basically remained stable,meeting with the admission requirements of “standard for pollution control on the security landfill site for hazardous wastes”.With the increase of leaching temperature,the arsenic leaching concentration could as well climb slightly.After stabilizing treatment of the waste residue containing arsenic,chemical forms of arsenic might be changed,and biological effectiveness and toxicity of arsenic could be changed gradually into small toxicity and high stability.But mineral composition and chemical composition of the waste residue are different,and the migration and transformation of arsenic form is also slightly different.%通过“硫酸－硝酸法”浸出实验，以砷的浸出浓度为控制指标，用 FeCl2为稳定剂，对含砷废渣进行了稳定化处理研究．考察了 Fe ／As 摩尔比、pH 值、废渣粒度、浸出温度和稳定处理时间对砷浸出浓度的影响，通过对比稳定化处理前后砷的形态变化，探讨砷的迁移转化规律．结果表明，砷的浸出浓度随 FeCl2投加量增加而降低，当 Fe ／As 摩尔比≥1．0，pH ＝6．5～7．5时，常温下稳定化处理时间≥60 min，砷浸出浓度低于2．5 mg／L 且基本保持稳定，达到“危险废物填埋污染控制标准”的入场要求；随着浸出温度的升高，砷的浸出浓度略有升高；含砷废渣经稳定化处理后，砷从生物有效性和毒性大的形态逐渐转化为毒性小、稳定性高的形态，但废渣的矿物组成和化学组成不同，砷形态的迁移转化也略有不同．
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