Hydrogeochemical and mineralogical characteristics related to heavy metal attenuation in a stream polluted by acid mine drainage:A case study in Dabaoshan Mine,China  

作　　者：Huarong Zhao Beicheng Xia Jianqiao Qin Jiaying Zhang 

机构地区：[1]School of Environmental Science and Engineering,Sun Yat-Sen University,Guangzhou 510275,China [2]School of Environmental Science and Engineering,Guilin University of Technology,Guilin 541004,China [3]Guangdong Provincial Academy of Environmental Science,Guangzhou 510045,China

出　　处：《Journal of Environmental Sciences》2012年第6期979-989,共11页环境科学学报（英文版）

基　　金：supported by the Guangdong Provincial Natural Science Foundation (No. 06202438);the Research Funds of the Guangxi Key Laboratory of Environmental Engineering,Protection and Assessment (No.GuiKeNeng 0801Z020)

摘　　要：Dabaoshan Mine,the largest mine in south China,has been developed since the 1970s.Acid mine drainage （AMD） discharged from the mine has caused severe environmental pollution and human health problems.In this article,chemical characteristics,mineralogy of ocher precipitations and heavy metal attenuation in the AMD are discussed based on physicochemical analysis,mineral analysis,sequential extraction experiments and hydrogeochemistry.The AMD chemical characteristics were determined from the initial water composition,water-rock interactions and dissolved sulfide minerals in the mine tailings.The waters,affected and unaffected by AMD,were Ca-SO4 and Ca-HCO3 types,respectively.The affected water had a low pH,high SO42 and high heavy metal content and oxidation as determined by the Fe^2＋ /Fe^3＋ couple.Heavy metal and SO4^2- contents of Hengshi River water decreased,while pH increased,downstream.Schwertmannite was the major mineral at the waste dump,while goethite and quartz were dominant at the tailings dam and streambed.Schwertmannite was transformed into goethite at the tailings dam and streambed.The sulfate ions of the secondary minerals changed from bidentate-to monodentate-complexes downstream.Fe-Mn oxide phases of Zn,Cd and Pb in sediments increased downstream.However,organic matter complexes of Cu in sediments increased further away from the tailings.Fe^3＋ mineral precipitates and transformations controlled the AMD water chemistry.Dabaoshan Mine,the largest mine in south China,has been developed since the 1970s.Acid mine drainage （AMD） discharged from the mine has caused severe environmental pollution and human health problems.In this article,chemical characteristics,mineralogy of ocher precipitations and heavy metal attenuation in the AMD are discussed based on physicochemical analysis,mineral analysis,sequential extraction experiments and hydrogeochemistry.The AMD chemical characteristics were determined from the initial water composition,water-rock interactions and dissolved sulfide minerals in the mine tailings.The waters,affected and unaffected by AMD,were Ca-SO4 and Ca-HCO3 types,respectively.The affected water had a low pH,high SO42 and high heavy metal content and oxidation as determined by the Fe^2＋ /Fe^3＋ couple.Heavy metal and SO4^2- contents of Hengshi River water decreased,while pH increased,downstream.Schwertmannite was the major mineral at the waste dump,while goethite and quartz were dominant at the tailings dam and streambed.Schwertmannite was transformed into goethite at the tailings dam and streambed.The sulfate ions of the secondary minerals changed from bidentate-to monodentate-complexes downstream.Fe-Mn oxide phases of Zn,Cd and Pb in sediments increased downstream.However,organic matter complexes of Cu in sediments increased further away from the tailings.Fe^3＋ mineral precipitates and transformations controlled the AMD water chemistry.

关 键 词：acid mine drainage Dabaoshan Mine heavy metal attenuation hydrogeochemical PHREEQC 

分 类 号：P641.3[天文地球—地质矿产勘探] X751.03[天文地球—地质学]