矿业工程研究
礦業工程研究
광업공정연구
Mineral Engineering Research
2015年
4期
68-74
,共7页
砷%氯化亚铁%稳定化处理%浸出浓度%重金属形态
砷%氯化亞鐵%穩定化處理%浸齣濃度%重金屬形態
신%록화아철%은정화처리%침출농도%중금속형태
arsenic%ferrous chloride%stabilization treatmeint%leaching concentration%chemical speciation of heavy metals
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．
通過“硫痠－硝痠法”浸齣實驗，以砷的浸齣濃度為控製指標，用 FeCl2為穩定劑，對含砷廢渣進行瞭穩定化處理研究．攷察瞭 Fe ／As 摩爾比、pH 值、廢渣粒度、浸齣溫度和穩定處理時間對砷浸齣濃度的影響，通過對比穩定化處理前後砷的形態變化，探討砷的遷移轉化規律．結果錶明，砷的浸齣濃度隨 FeCl2投加量增加而降低，噹 Fe ／As 摩爾比≥1．0，pH ＝6．5～7．5時，常溫下穩定化處理時間≥60 min，砷浸齣濃度低于2．5 mg／L 且基本保持穩定，達到“危險廢物填埋汙染控製標準”的入場要求；隨著浸齣溫度的升高，砷的浸齣濃度略有升高；含砷廢渣經穩定化處理後，砷從生物有效性和毒性大的形態逐漸轉化為毒性小、穩定性高的形態，但廢渣的礦物組成和化學組成不同，砷形態的遷移轉化也略有不同．
통과“류산－초산법”침출실험，이신적침출농도위공제지표，용 FeCl2위은정제，대함신폐사진행료은정화처리연구．고찰료 Fe ／As 마이비、pH 치、폐사립도、침출온도화은정처리시간대신침출농도적영향，통과대비은정화처리전후신적형태변화，탐토신적천이전화규률．결과표명，신적침출농도수 FeCl2투가량증가이강저，당 Fe ／As 마이비≥1．0，pH ＝6．5～7．5시，상온하은정화처리시간≥60 min，신침출농도저우2．5 mg／L 차기본보지은정，체도“위험폐물전매오염공제표준”적입장요구；수착침출온도적승고，신적침출농도략유승고；함신폐사경은정화처리후，신종생물유효성화독성대적형태축점전화위독성소、은정성고적형태，단폐사적광물조성화화학조성불동，신형태적천이전화야략유불동．
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.
