金尾矿混凝土中重金属长期浸出行为研究
Long Term Leaching Behavior of Heavy Metals in Gold Tailings Concrete
罗作球 1李晓光 2张凯峰 3付万长 2童小根 1孟刚1
作者信息
- 1. 中建西部建设北方有限公司,西安 710065
- 2. 长安大学建筑工程学院,西安 710064
- 3. 中建西部建设北方有限公司,西安 710065;长安大学建筑工程学院,西安 710064
- 折叠
摘要
为了探究金尾矿作为混凝土细骨料使用时的重金属浸出风险,分析了金尾矿混凝土在不同pH浸提液中的浸出行为以及长期浸出特性,并运用动力学模型,预测了未来30年的重金属累积浸出量.结果表明,金尾矿中的Ba、Cd、Cr、Pb、Mn、Cu含量均超过了中国土壤元素背景值,其中Ba、Cd、Pb、Mn、Cu的浸出量较为显著.金尾矿掺量与重金属浸出量呈正相关,重金属累积浸出量在16 d后显著降低.根据30年浸出量预测,Pb、Cu、Ba的浸出量为2～3 mg/L,Cd、Cr和Mn的浸出量在1 mg/L以内,表明金尾矿在混凝土中的固化效果良好,重金属长期浸出风险较低.
Abstract
An investigation was undertaken to assess the potential for heavy metal leaching from gold tailings(GTs)when used GTs as fine aggregate for concrete.The leaching behavior in different pH leaching solutions and long-term leaching features of gold tailings concrete were studied.A kinetic model was used to predict the total amount of heavy metal leaching that will occur in next thirty years.The results reveal that the levels of Ba,Cd,Cr,Pb,Mn and Cu in GTs exceed the natural levels of these elements found in Chinese soil.Significantly,the leaching of Ba,Cd,Pb,Mn and Cu is more evident.GTs content shows a positive correlation with the leaching amount of heavy metals,and the cumulative leaching amount of heavy metals drops dramatically after 16 d.Based on 30 years leaching amount prediction,the leaching amount of Pb,Cu and Ba is 2～3 mg/L,while the leaching amount of Cd,Cr and Mn is less than 1 mg/L.These findings indicate that the GTs is sufficiently cured in concrete,thereby reducing the risk of long-term leaching of heavy metals.
关键词
金尾矿/混凝土/重金属/长期浸出/动力学模型/预测Key words
gold tailings/concrete/heavy metal/long-term leaching/kinetic model/forecast引用本文复制引用
基金项目
中建西部建设科技研发项目(ZX-202108)
陕西省科协企业创新争先青年人才托举计划(2021-1-2)
出版年
2024
国家科技期刊平台
NSTL
万方数据