基于土柱模拟降雨对铜尾矿重金属淋溶进入下伏土壤的生态风险研究

浏览次数：19

分享到:

摘要：

为探究铜尾矿重金属释放对环境的影响,通过动态淋溶实验,配置初始pH=7.2的人工模拟雨水为淋滤液,采用柱状淋溶装置进行尾矿重金属淋出实验,探究中卫某铜尾矿重金属的淋溶释放特征,评估尾矿重金属淋溶的生态风险.结果表明,尾矿中Cu、Zn、As、Cd和Pb平均质量含量分别为2130.30、105.10、234.41、0.72和64.57mg·kg-1,均超出宁夏土壤重金属元素背景值.淋溶10次后,尾矿中Cd、Zn、Pb、As、Cu等重金属的释放率分别为1.98%、0.32%、0.30%、0.15%、0.01%,即Cd的释放率最高.淋溶后,尾矿重金属质量含量明显下降,其中0~5cm深度尾矿重金属含量下降最多,As的释放量最大,重金属向下层迁移明显.尾矿中Cu、Pb、Cd和Zn主要淋失碳酸盐结合态,As主要淋失可交换态,As和Cd的淋溶风险较高.Cu是尾矿重金属中关键的生态风险因子,尾矿中Cd和Cu为高风险,As、Zn和Pb为中风险.

In order to explore the impact of heavy metal release from copper tailings on the environment,a dynamic leaching experiment was conducted by setting artificial simulated rainwater with initial pH of 7.2 as leachate,and a column leaching device was used to conduct the leaching experiment of heavy metals from tailings of a Zhongwei copper tailings,so as to explore the leaching and release characteristics of heavy metals from the tailings and assess the ecological risk of heavy metal leaching from the tailings.The results showed that the average mass contents of Cu,Zn,As,Cd and Pb in the tailings were 2130.30,105.10,234.41,0.72 and 64.57 mg·kg-1,which exceeded the background values of heavy metal elements in Ningxia soil.After leaching for 10 times,the release rates of Cd,Zn,Pb,As,Cu and other heavy metals in the tailings were 1.98%,0.32%,0.30%,0.15%,0.01%,respectively,that is,the release rate of Cd was the highest.After leaching,the heavy metal content of tailings decreased significantly,among which the heavy metal content of tailings at 0-5 cm depth decreased the most,the release of As was the largest,and the heavy metal migrated to the lower layer obviously.In the tailings,Cu,Pb,Cd and Zn are mainly leached out of carbonate binding state,and As is mainly leached out of exchangeable state.The leaching risk of As and Cd is higher.Cu is the key ecological risk factor of heavy metals in tailings,Cd and Cu are high risk,and As,Zn and Pb are medium risk.

作者：

贺婧金安妮张扣扣马娟罗玲玲任惠芹钟艳霞

He Jing;Jin Anni;Zhang Koukou;Ma Juan;Luo Lingling;Ren Huiqin;Zhong Yanxia(State Key Laboratory of Land Degradation and Ecological Restoration in Northwest China,Ningxia University,Yinchuan 750021,China;College of Ecology and Environment,Ningxia University,Yinchuan 750021,China;School of Geographic Science and Planning,Ningxia University,Yinchuan 750021,China;Ecological Environment Monitoring Center of Ningxia Hui Autonomous Region,Yinchuan 750002,China)

机构地区：

宁夏大学西北土地退化与生态恢复国家重点实验室培育基地宁夏大学生态环境学院宁夏大学地理科学与规划学院宁夏回族自治区生态环境监测中心

引用本文：

《betway官方app 学报（自然科学版）》 CAS 北大核心 2024年第3期119-130,共12页

Journal of Henan Normal University(Natural Science Edition)

基金：

国家重点研发项目(50578020) 宁夏自然科学基金(2023AAC02028,2021AAC03032).

关键词：

铜尾矿重金属淋溶生态风险

copper tailing heavy metal leaching ecological risk

分类号：

X703.5 [环境科学与工程—环境工程]