广西老厂铅锌尾矿重金属动态纵向释放迁移规律  

Dynamic vertical release and migration of heavy metals from Laochang lead-zinc tailings in Guangxi

作　　者：郑锦一 张学洪[1,2] 刘杰[1,2] 艾涛[1] ZHENG Jin-yi;ZHANG Xue-hong;LIU Jie;AI Tao(Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology,Guilin University of Technology,Guilin 541006,China;Guangxi Collaborative Innovation Center for Water Pollution Control and Water Safety in Karst Area,Guilin University of Technology,Guilin 541006,China)

机构地区：[1]桂林理工大学广西环境污染控制理论与技术重点实验室,广西桂林541006 [2]桂林理工大学广西岩溶地区水污染控制与用水安全保障协同创新中心,广西桂林541006

出　　处：《桂林理工大学学报》2020年第3期580-586,共7页Journal of Guilin University of Technology

基　　金：广西科技重大专项(桂科AA17204047);广西高等学校高水平创新团队及卓越学者计划项目(桂财教函[2018]319)。

摘　　要：为深入研究岩溶地区铅锌老矿遗留尾矿的重金属动态迁移规律,采集广西老厂铅锌矿尾矿库样品,进行动态淋溶模拟实验及相关分析。结果表明:尾矿样品的NP/AP>3∶1且NAG<10,属于非产酸性尾矿,对酸性淋溶液有较强的中和能力。该尾矿样品中重金属的潜在迁移能力顺序为Zn>Cd>Pb。尾矿样品中Pb、Zn、Cd 3种重金属的释放受酸性淋溶液的pH值影响较大,pH=2时累计溶出量最大,分别为Pb 0.82 mg/kg、Zn 86.32 mg/kg、Cd 2.45 mg/kg。随着淋溶时间的变化,Pb、Zn、Cd均呈现前期快速、后期慢速的溶出特征。不同尾矿粒径对样品中Pb、Zn、Cd的溶出有一定的影响,但不显著,在淋溶初期,重金属的溶出速率较快,呈线性增长;而随着淋溶的进行,溶出速率逐渐降低,累计溶出量达到峰值。The karst area in southwest China has an unique unique environment.The erosion of rocky desertification resulting in thin soil layer and rapid soil erosion rate of the surrounding limestone soil causes heavy metals pollution.In order to further study the dynamics of heavy metal migration in the tailings of the Laochang lead-zinc ore in the karst area,the samples from the tailings pond in the Laochang were collected,and a dynamic leaching simulation experiment and related analysis were performed.The results show that the tailings samples(NP/AP>3∶1 and NAG<10)belong to non-acid-producing tailings and have strong neutralizing ability to acid leaching solution.The order of potential migration capacity of heavy metals in this tailings samples is Zn>Cd>Pb.The release of Pb,Zn,and Cd in tailings samples is greatly affected by pH of the acidic leaching solution.The cumulative solubility is maximum when pH=2.0,and the solubility is Pb 0.82 mg/kg,Zn 86.32 mg/kg,and Cd 2.45 mg/kg respectively.With the change of leaching time,the heavy metals Pb,Zn,and Cd all showed fast leaching characteristics in the early stage and slow leaching in the later stage.Different particle sizes have certain effect on the dissolution of heavy metals Pb,Zn,and Cd in tailings samples,but they are not significant.In the initial leaching period,the dissolution rate of heavy metals is fast and linearly increases.The rate gradually decreases and the cumulative dissolution volume reaches a peak.

关 键 词：岩溶地区 铅锌矿 尾矿 重金属 动态淋溶 纵向迁移 老厂 

分 类 号：X54[环境科学与工程—环境工程]