广东凡口PbZn尾矿中重金属的表生地球化学行为及其对矿山环境修复的启示

,,,.Pb2Zn[J].,2005,25(3):414-422ZHUJibao,CHENFanrong,LULong,etal.HeavymetalgeochemistrybehaviorduringtheoxidationoftheFankouPb2ZnminetailingsinGuangdongprovinceandtheimplicationsforenvironmentalremediationofthemines[J].ActaScientiaeCircumstantiae,2005,25(3):414-422Pb2Zn1,2,1,3,1,1,211,51064021,100039:,,1.(31%),017%112%,.110%,.(),,(),;();,,PbZn70%..,.,Dold,2(:pH=415,1moL1L-1NH4Ac),6,Ac-Pb2+,Ac-.:;;;;:025322468(2005)0320414209:X751,P595:AHeavymetalgeochemistrybehaviorduringtheoxidationoftheFankouPb2ZnminetailingsinGuangdongprovinceandtheimplicationsforenvironmentalremediationoftheminesZHUJibao1,2,CHENFanrong1,3,LULong1,XIEXinghua1,21.GuangzhouInstituteofGeochemistry,ChineseAcademyofSciences,Guangzhou5106402.GraduateSchool,ChineseAcademyofSciences,Beijing100039Abstract:Themineralconstituent,contentandconfigurationofheavymetalsinnewlyreleasedtailingsandintheprofilesoftailingssite1werestudiedintheFank2ouZn2Pbminingfield,China,byusingmineralogicalandchemicalanalysisaswellassequentialextractionexperiment.TheconcentrationofPb,Znwasratherhighintheoxidizedzone(induratedlayer),andthatintheunderlyingsub2oxidizedzonedecreasestolevelsthatareunbelievablylowforPb2Znminetailings.Cal2culationsindicatedthattheamountofZnandPbleachedoutfromtheoxidizedandsub2oxidizedzoneswasmorethan30%and70%,respectively.Theseobserva2tionssuggestedthattheheavymetalsreleasedfrommetalsulfidesshouldbere2immobilizedbysecondarymineralsintheoxidizedzone,ratherthanprimaryminerals,andtheycouldbeleachedoutfromthesub2oxidizedenvironmentduetothelowrateofoxidativedissolution,whichpreventedtheprecipitateofsecondarymineralsinsignificantamount.Thus,coverscenarioswhichestablishedasub2oxidizedenvironmentunderthecoverlayermightnotbeeffectiveinpreventingheavymetalre2leasefromminetailings.Sequentialextractionandmineralogicalstudiesindicatedthat,inadditiontoheavymetalleaching,oxidationoftheminetailingsincreasedthemobilityofre2sidualZnandCu,whilePbremainedimmobileduetotheformationofinsolublesecondarymineralssuchasanglesite(PbSO4).Byusing(theseven2stepextractiontechniquedevelopedbyDold,galenadissolvedinsignificantamountatstep2,whichwasmostprobablyduetothestrongcomplexingforceofPb2+withAc-.Meanwhileothermetalsulfidesdissolvedatstep6,whichindicatedthatextractiontechniquesinwhichAc-2bearingsolutionsmightnotbeappropriatetoevaluatethemobilityofleadinnature.Keywords:Heavymetals;sequentialextraction;environmentalremediation;minetailings:2004205225;:2004212228:(2000[524]):(1977),,;3(),[e-mail]25320053ACTASCIENTIAECIRCUMSTANTIAEVol.25,No.3Mar.,2005,,[16].,[46],[7].Pb2Zn,40,.Pb2Zn[8];[9].,,,.,,Pb2Zn.,,,,,().,,[1012],.,,.,,1,PbZn;,,.1,,[19].,1719,1912,72818,304d,1665mm,49,.10km,3.1206070,1980.,,2km2.,,,.012m,,().,,.2211.,3,6,.,1,011117m,013m,3(),,5080m.3,.21223,,(BSEI).BSEIJEOLJXA8800M,20kV21010-8A..KClO3,.HNO3.,200,X(XRD)..012000g,8mL24h,,1mL(1moLL-1)20min(4800rmin-1).,8mLHF3mLHClO434d.,HClO4HF.1mL(1moLL-1),250mL.ICP2AES,ICP2MS.,[1317].Dold[18],75143:Pb2Zn,.DoldPb2Zn,1..1Table1SequentialextractionprocedureT111000g,30mL,1h,.T21moLL-1NH4Ac10mL,HAcpH415,2h.,5mL2,.T3012moLL-1(NH4)2C2O410mL,H2C2O4pH310,,1h.,5mL2,.T4012moLL-1(NH4)2C2O410mL,H2C2O4pH310,802h.,5mL2,.T535%()H2O210mL,801h.,5mL2,.T6KClO3750mg,12moLL-1HCl10mL,30min,5mL2,;4moLL-1HNO310mL(963)20min,,5mL2,.T7,HNO3PHFPHClO4PHCl10mL.1moLL-1,400mL.3311,,,,[19].2.,1.,,,(3).XRD,().,XRD,(12m),(),,.,2,X2,(2%).2,,1(,),.,PbZn017%112%,269mgkg-1(3).,(1).2Table2CharacteristicsandmineralcompositionofFankouPb2ZnminetailingsPm101101235%16%12%4%9%218%(19%)2014015312%1615%5016%1119%6%417%30170181814%5818%1417%7%612%41111122112%54%1410%8%811%51161172413%5118%1519%7%610%61910%2410%610%8%3110%614253Table3ConcentrationoftantalumintheminetailingsandconstituentmineralsFePbP(mgkg-1)ZnP(mgkg-1)CuP(mgkg-1)NiP(mgkg-1)CoP(mgkg-1)CdP(mgkg-1)CrP(mgkg-1)CaO112122%497657916616718163215131426313320154%25173%302545176219140215611645016736175%34115%1188209837133441303128019756210038105%43160%202830075611128416101696110036140%52135%150922535416730180318301524816735181%619192%703812206269133211104173410356810013120%Py(14)45117%3007003004000300100Sph(5)1180%0655700130050001200200Ga(10)0%86300010030010010000Cal(10)0128%300300200200030055128%Ser(8)0178%9007002005002006000148%Feo(7)49194%700364001100170020011000178%:,.Py2,Sph2,Ga2,Cal2,Ser2,Feo2()..1(:(211))Fig.1Sectionmapshowingtheheavymetalprofilesatdifferentsamplingsites31212,PbZnCu15%.,FeZnCuCoCdNiT6,T5.,.CrT7.T2,T2T6,12T7,,T6T7.4411,.1Pb2Zn,Fe3+,,.,014015m312%,Fe3+.31%,12122%,.,,,.,[2023],Fe2+,Fe2+,Fe2+Fe3+,Fe3+Fe2+,,Fe2+[20,23].:7143:Pb2ZnFe2++14O2+H+Fe3+12H2O(1)FeS2+14Fe3++8H2O15Fe2++2SO2-4+16H2(2),,(1)(2),Fe3+,Fe3+.,(2).,,(1)[15],.,.,,2.,.2(AG14(2);H26();T1T7(1))Fig.2RatiohistogramofFractionaldistributionofheavymetalsextractedinthesequentialextractions,2070,,.,115.,,2.2070,110%115%210%310%[24],7015%,35%,PbZn86%94%[25],3182%814254195%8131%1116%,PbZn68369654mgkg-1647510117mgkg-1,PbZn,(1).3PbZn,,60cmPbZn1P3,1P20,,.,,.,,,,.,(30%),.,().()Fe(OH)3FeOOH,Fe2O3H2O,3()19%,16%.6%,,30%.2070(Pb:68369654mgkg-1;Zn: