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I摘要线路板污泥和酸性蚀刻废液对环境和人体健康造成的危害已经引起人们的极大关注，是国内外公认的公害之一。而线路板污泥和酸性蚀刻废液中有价金属铜的含量远高于铜矿的开采品位，是一种廉价的二次可再生资源。从线路板废弃物中回收有价金属，提高二次资源的利用率，对于满足我国国民经济发展的需要具有实际意义。本文对以线路板污泥和酸性蚀刻废液为研究对象，提出了超声波辅助线路板污泥和酸性蚀刻废液同时处理回收金属铜和铁的处理工艺，并对浸出、铜铁分离、铜钙分离、无害化处理过程的工艺条件和机理进行了研究和探讨。对超声波辅助线路板污泥和酸性蚀刻废液同时处理回收金属铜和铁的处理工艺进行了研究，对比了在超声波条件下与没有超声波作用下各金属的浸出率，并研究了不同pH值、温度、超声波功率和是否添加石灰对铜铁分离以及铜钙分离的影响，得出了全流程的较理想工艺条件。研究结果表明，超声波在第一步铜铁分离的过程中具有促进作用。在25℃、300r/min和300W超声波的条件下，先用酸性蚀刻废液调节线路板污泥泥浆的pH值至1.5，然后再用石灰把它的pH值调至2.5。铜和铁的浸出率分别达到了93.76%和2.07%。铜进入到液相而铁仍然留在固相，两者得到有效的分离。而超声波在第二步铜铁分离的过程中没有促进作用。在25℃、300r/min的条件下，用石灰调节至pH值为5.5，从铜铁分离过程中产生的浸出液和漂洗水的混合液中沉淀铜。而转移到固相中的铜百分含量和残留在固相中的铁百分含量分别为99.99%和1.29%。大部分的铜转移到固相中而大部分的钙保留在液相中，因此铜钙得到了有效地分离。铜铁分离后的氢氧化铁可以进一步制备三氯化铁回用到生产过程当中；而铜钙分离后的氢氧化铜可以制备五水硫酸铜,液相中的二水氯化钙可以浓缩生产二水氯化钙产品。试验结果表明了该工艺的可行性并成功地应用于中试阶段。研究结果表明:该工艺能够有效地回收线路板污泥和酸性蚀刻废液中的有价金属，同时，整个工艺过程不产生废水，产生的少量废渣符合安全排放的标准可应用于水泥生产工业，不会对环境产生危害，达到了线路板废弃物资源化和无害化处理的目的。关键词：超声波；金属回收；线路板污泥；酸性蚀刻废液；同时处理IIAbstractThePCBwastesludgeandPCBspentacidetchingsolutioncancauseharmtotheenvironmentandhumanhealth,whichisoneofrecognizedhazardsathomeandabroad.ThePCBwastesludgeandPCBspentacidetchingsolutionwhichcontainingmuchhighercontentofcoppercomparetothemetal-gradeoreischeapsecondaryrenewableresource.RecoveringthevaluablemetalsfromthePCBwasteandimprovingtheutilizationratioofthesecondaryresourcearemeaningfultosatisfytheneedoftheeconomicdevelopmentofournationaleconomy.Inthispaper,thePCBwastesludgeandPCBspentacidetchingsolutionistheresearchobject.Anewtechnologyisdeveloped,describedas“TreatmentprocesscraftofultrasonicrecoveryofcopperandironthroughthesimultaneousutilizationofPCBspentacidetchingsolutionandPCBwastesludge”.Theprocesscraftconditionsandmechanismsofleaching,separationofcopperandiron,andseparationofcopperandcalciumareinvestigated.ThetreatmentprocesscraftofultrasonicrecoveryofcopperandironthroughthesimultaneousutilizationofPCBspentacidetchingsolutionandPCBwastesludgewasstudied.Theleachingratesofeachmetalfromtheprocessofcopperandironseparation,copperandcalciumseparationwithassistanceofultrasoundwascomparedwiththeonewithoutassistanceofultrasoundandtheeffectsofpHvalue,reactiontemperature,ultrasonicpowerandwhetheraddinglimehavebeeninvestigatedinthepaper.Asaresult,themoredesirableprocessconditionsofthewholeprocesswereobtained.Thestudypresentedthatultrasoundcanenhancetheseparationefficiencyofcopperandironinthefirststep,copperandironseparation.At25◦C,stirringat300rpmandultrasonicpowerat300W,usingspentacidetchingsolutiontoregulatethepHvalueofPCBwastesludgeto1.5thenaddedlimetotuneitspHvalueto2.5.Theleachingratesofcopperandironreached93.76%and2.07%respectively.Copperandironwereeffectivelyseparatedastheformerstayedinaqueoussolutionandthelatterremainedinsolidphase.However,ultrasoundhasnosenseontheseparationefficiencyofcopperandcalciuminthesecondstep,copperandcalciumseparation.At25◦C,stirringat300rpmwithpH5.5,limewasusedtoprecipitatecopperfromthemixtureofleachateandrinsingwaterproducedduringtheseparationofcopperandiron.Thepercentageofcopperandcalciumprecipitatedandsettledassolidswere99.99%and1.29%respectively.Thus,copperandcalciumwereeffectivelyseparatedwithmostofthecopperIIIstayedinsolidphaseandmostofthecalciumremainedinaqueoussolution.Theironhydroxideproducedintheprocessofcopperandironseparationcanbemadefurtherascommercialrateferricchloridetoreuseintheproduceprocess.Thecopperhydroxideproducedintheprocessofcopperandcalciumseparationcanbemadefurtherascommercialratecoppersulfateandthecalciumchlorideintheliquidphasecanbecondensedtoproducedcommercialratecalciumchloridedehydrate.Thelabresultsshowedthetechnicalfeasibilityoftheprocessandhadbeensuccessfullyappliedtopilot-scaletest.Theresultinthispaperindicated:theprocesscraftcanefficientlyrecovervaluablemetalsfromPCBspentacidetchingsolutionandPCBwastesludge.Meanwhile,thewholeprocessdidnotproducewastewater,whilethegeneratedminimumharmlessresiduesreachingthestandardofsafeemissionwhichcanbeusedasrawmaterialforcementkiln.Thus,thetechnologyprogramhasdualeconomicandenvironmentalbenefitsandthestudyresultshassomereferencevalueandguidingsignificanceforthetreatmentofelectroplatingsludgeinanindustrialtest.Thus,thetreatmentprocesscraftwhichdon’tdoharmtotheenvironmentcanachievetheaimofresourcesandharmlessnesstreatingthePCBwaste.Keywords:ultrasound;metalrecovery;acidicprintedcircuitboards(PCB)spentetchingsolution;printedcircuitboards(PCB)wastesludge;simultaneoustreatmentIV目录摘要.............................................................................IAbstract...........................................................................II第一章绪论........................................................................11.1引言..................................................................................................................................................11.2PCB铜蚀刻废液和线路板污泥的来源...........................................................................................11.2.1PCB铜蚀刻废液的产生.........................................................................................................11.2.2