黄金尾砂重金属淋溶释放规律  

Leaching characteristics and release rule of heavy metals from gold tailings

作　　者：钱玲 李冰[1,3] 陈希 李先宁 林海[1,3] Qian Ling;Li Bing;Chen Xi;Li Xianning;Lin Hai(School of Energy and Environmental Engineering,University of Science and Technology Beijing,Beijing 100083,China;Sino-Japan Friendship Center for Environmental Protection,Beijing 100029,China;Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants,Beijing 100083,China;School of Energy and Environment,Southeast University,Nanjing 210096,China)

机构地区：[1]北京科技大学能源与环境工程学院,北京100083 [2]中日友好环境保护中心,北京100029 [3]工业典型污染物资源化处理北京市重点实验室,北京100083 [4]东南大学能源与环境学院,南京210096

出　　处：《东南大学学报（自然科学版）》2020年第6期1084-1089,共6页Journal of Southeast University：Natural Science Edition

基　　金：“十二五”国家科技重大专项资助项目(2015ZX07205003);国家重点研发计划资助项目(2018YFC0604604).

摘　　要：为探究黄金尾砂中重金属释放规律及其环境影响,通过动态淋溶实验研究了某地黄金矿山尾砂中重金属淋溶释放特征.配制初始pH值分别为3.0、4.5和6.0的人工模拟酸雨淋溶液,使用柱式淋溶装置开展黄金尾砂中重金属淋出动力学实验.实验结果表明:尾砂中重金属Mn属于轻度污染,Zn和Cu属于中度至严重污染,Pb为严重污染,而As为严重至极度污染;随着淋溶时间的增加,不同初始pH值组尾砂淋出液的pH值均逐渐升高,而后稳定在7.9~8.2之间,表明该尾砂碱性矿物含量较高,具有一定的酸缓冲能力,而淋出液电导率值均呈现先急剧减小随后趋于稳定的趋势;重金属Zn和Mn从尾砂中的释放率高于As、Cu和Pb,而Pb和Zn对酸性淋溶液的敏感程度相对较高;一级动力学方程和双常数速率方程可较好地描述尾砂中As、Pb、Cu、Mn和Zn淋出的动力学过程,抛物线方程也能较好地描述Cu、Mn淋出的动力学过程;尾砂中重金属淋溶释放是由多种因素协同控制的复杂过程.To explore the rule of heavy metal release in gold tailings and its impacts on the environment,the leaching and release characteristics of heavy metals in tailings from a gold mine were studied by a dynamic leaching experiment.The artificial simulated acid rain solution with initial pH values of 3.0,4.5 and 6.0 was prepared,and the kinetics experiment of heavy metal leaching from gold tailings was carried out with a column leaching device.Experimental results show that the heavy metal Mn in tailings is slightly polluted,Zn and Cu are moderately or severely polluted,Pb is severely polluted,and As is severely or extremely polluted.With the increase of leaching time,the pH values of the tailing leaching solutions in different initial pH value groups gradually increase,and then stabilize between 7.9 and 8.2,indicating that the tailings have a higher alkaline mineral content and a certain acid buffering capacity,while the conductivity values of the leaching solutions all show a sharp decrease first and then tend to be stable.The release rates of Zn and Mn from tailings are both higher than those of As,Cu and Pb,while the sensitivities of Pb and Zn to the acid leaching solution are relatively higher among the studied heavy metals.The first-order kinetics equation and the double-constant rate equation can better describe the leaching kinetics of As,Pb,Cu,Mn,and Zn from tailings,and the parabolic equation can also describe the leaching kinetics of Cu and Mn well.The leaching and release of heavy metals in tailings is a complex process controlled by multi-factors.

关 键 词：黄金尾砂 重金属 淋溶特征 释放动力学模型 模拟降雨 

分 类 号：X53[环境科学与工程—环境工程]