摘要
以高硫煤矸石为研究对象,采用静态淋溶试验探究在模拟降雨pH分别为2、3、5、7的条件下,煤矸石中重金属Mn、Cu、Zn和SO_(4)^(2-)的释放规律及动力学行为。结果表明,酸性条件更有利于重金属和SO_(4)^(2-)释放,随时间增加表现为先快速释放后逐渐稳定的趋势。在降雨pH为3时,重金属Mn、Cu、Zn的累积释放量最大,分别达到60.40、29.11、5.86 mg/kg。在降雨pH为2时,SO_(4)^(2-)的累积释放量最大,达到了25027.27 mg/kg。动力学结果表明,重金属释放由界面化学反应控制,而SO_(4)^(2-)由固体膜层界面和扩散混合控制,且在重金属与SO_(4)^(2-)释放的过程中产生大量H^(+),使淋出液pH<1.52。本研究结果可以从污染物源头释放的角度为煤矸石堆场重金属及SO_(4)^(2-)污染防控和监管提供理论依据。
The release rules and kinetic behaviors of heavy metals(Mn,Cu,Zn)and SO_(4)^(2-) from coal gangue were investigated under the conditions of simulated rainfall pH value of 2,3,5 and 7 respectively using static leaching test with high sulfur coal gangue as the research object.The results show that the acidic conditions are more favorable for the release of heavy metals and SO_(4)^(2-),which shows a trend of rapid release followed by gradual stabilization with increasing of time.The cumulative release of Mn,Cu and Zn is the highest at rainfall pH value of 3,reaching 60.40,29.11 and 5.86 mg/kg,respectively.The cumulative release of SO_(4)^(2-) is biggest at the precipitation pH value of 2,reaching 25027.27 mg/kg.The kinetics results show that heavy metals release is controlled by interfacial chemical reactions,while SO_(4)^(2-) is controlled by interfacial and diffusive mixing of solid film layers,and a large amount of H^(+)is generated during the release of heavy metals and SO_(4)^(2-),which makes the leachate pH<1.52.The results of this study can provide a theoretical basis for heavy metals and SO_(4)^(2-) pollution prevention,control,and regulation in coal gangue dumps from the perspective of pollutant release at source.
作者
卢欢
董颖博
林海
LU Huan;DONG Ying-bo;LIN Hai(School of Energy and Environmental Engineering,University of Science and Technology Beijing,Beijing 100083,China;Beijing Key Laboratory on Resource-oriented Treatment of Industrial Pollutants,Beijing 100083,China)
出处
《有色金属（冶炼部分）》
CAS
北大核心
2023年第1期102-109,共8页
Nonferrous Metals（Extractive Metallurgy)
基金
国家重点研发计划项目(2019YFC1805001)。
