高压脉冲电絮凝法处理电镀废水朱小梅

朱小梅,赵　娜,刘晓星,公维民,孙　冰＊(,　116026)　　　:在电解槽中将铁板作为电极,探讨了高压脉冲电絮凝技术处理含Cr3+,Cr6+和Zn2+的电镀废水,并与直流电絮凝方法作了对比.实验结果表明,高压脉冲电絮凝法处理的工业电镀废水出水水质较好,在最优条件下,处理后的废水中总铬和Cr6+含量均为～0.1mg/L,Zn2+含量为～0.6mg/L,pH=8.3,均达到国家规定的排放标准水平.该法运行方便,处理时间短、与直流电絮凝法相比能量效率高,是较理想的电镀废水治理工艺,具有很好的推广应用价值.:;;;TreatmentofElectroplatingWastewaterbyHighVoltagePulsedElectrocoagulationZHUXiao-mei,ZHAONa,LIUXiao-xing,GONGWei-min,SUNBing(CollegeofEnviromentalScienceandEngineering,DalianMaritimeUniversity,Dalian116026,China)Abstract:HighvoltagepulsedelectrocoagulationtechnologywasdesignedtoremovethetotalCr,Cr(Ⅵ)andZn(Ⅱ)ofelectroplatingwastewaterbyusingironplateaselectrodeinthehydroelectricbath,andthemethodwascomparedwiththedirectcurrentelectrocoagulationmethod.Theinitialmassconcentrationsofthewastewateraretotalρ(Cr)=168.6mg/L,ρ(Cr(Ⅵ))=22.8mg/Landρ(Zn(Ⅱ))=29.9mg/L.Experi-mentalresultsindicatethatthehighvoltagepulsedelectrocoagulationtechnologycanremovetheelectroplatingwastewaterefficiently.AfteradjustingthepHto7-9byNaOH,theresidualmetalmassconcentrationsofthewastewaterunderlegallimitsofindustrialwater(GB8978-1996)areobtained,justafterabout8minute.ThetotalCrmassconcentrationisabout0.1mg/L,Cr(Ⅵ)massconcentrationisalsoabout0.1mg/L,Zn(Ⅱ)massconcentrationisabout0.6mg/Lwiththeoptimumexperimentalconditions.Comparedtothedirectcur-rentelectrocoagulationmethodandconventionalexistingtechniques,thehighvoltagepulsedelectrocoagulationtechnologyhasthemeritsofeasieroperating,shorterrunningtimeandhigherenergyefficiency.Thehighvolt-agepulsedelectrocoagulationtechonologyisanidealusingtechniqueforthetreatmenttotheelectroplatingwastewatercontainingchromiumandzincandhasagreatpotentialforindustrialapplication.Keywords:electrocoagulation;electroplatingwastewater;highvoltagepulse;heavymetal,Cr,Cd,Cu,NiZn.,,,.　:(20577004)＊27　2007　10河北大学学报(自然科学版)JournalofHebeiUniversity(NaturalScienceEdition)Vol.27Supp.Oct.2007,,,、、、、[1-5],,,,,,,;,.[6-8],、,、,,,,、,.,,、、,,,,.,Cr3+,Cr6+Zn2+,;.1　实验部分,Cr3+,Cr6+Zn2+(,1),,,3～10min.1mol/LNaOHpH.(DigitalPhosphorOscilloscope,TDS3032B)、;DDS-11A;-pHpH;Perkin-Elmer;(CJ/T71-1999)Gr6+;(GB11914-89)(COD).1　Tab.1　ParameterofelectroplatingwastewaterandthenationalstandardpHρ(Cr)/(mg·L-1)ρ(Cr6+)/(mg·L-1)ρ(Zn2+)/(mg·L-1)COD3.75168.622.829.9574(GB8978-1996)6～9()1.5　0.5　5　500()2　结果与讨论2.1　2.(7.2kW·h/m3),(2.5kW·h/m3),;,8min,;,COD,COD;,,pH、,pH,.·95·:2　Tab.2　ParameterofelectroplatingwastewaterwithdifferentdisposalmethodpHρ(Cr)/(mg·L-1)ρ(Zn2+)/(mg·L-1)COD5.037321.54104.236727.33282.2　pH,,、pH,NaOHpH,Cr3+,Zn2+,Fe3+.1pH,pH=6.68,,27.3mg/L3.0mg/L;pH,,pH=8.3,,0.6mg/L0.1mg/L,ρ(Cr6+)≤0.1mg/L,,pH8～9,ρ(Cr6+)Cr6+Cr3+;pH9.8,,pH,.1　pHFig.1　ResidualmetalmassconcentrationswithdifferentpHvalueA.,NaOHpH8.3;B.NaOHpH8.4,2　NaOHFig.2　ResidualmetalmassconcentrationswithdifferentaddingorderofNaOH2.3　NaOH,NaOH,2.,NaOHpH8.3,Cr,Cr6+Zn2+0.1,0.10.6mg/L;NaOHpH8.4,,0.8mg/L,0mg/L,;Cr6+～0.6mg/L,.,,NaOHpH.2.4　[9-10],,,(),1/2,1/2,,1/2,,·96·()20071/4,,.,,,,,.,.():FeFe2++2e-,　　　Cr6++3Fe2+Cr3++3Fe3+.():2H2O+2e-H2+2OH-.:Fe2+,OH-,,;Fe3+Cr3+Zn2+OH-.Fe2++2OH-Fe(OH)2,　　　　Fe3++3OH-Fe(OH)3,Cr3++3OH-Cr(OH)3,Zn2++2OH-Zn(OH)2.:,.,,,.,.、、.,,2BpHGr6+.3　结论1)Cr6+,Cr3+Zn2+,;、、,Cr6+2.5kW·h/m3,.2)pH,NaOH.:,NaOHpH8.3.3),、,;.　　　:[1],.[J].,2004,2:69-71.[2],.[J].,1994,14(5):20-22.[3]KURNIAWANTA,CHANGY,LOW,etal.Physico-chemicaltreatmenttechniquesforwastewaterladenwithheavymet-als[J].ChemicalEngineeringJournal,2006,118:83-98.[4]NAMASIVAYAMC,SURESHKUMARMV.Removalofchromium(Ⅵ)fromwaterusingsurfactantmodifiedcoconutcoirpithasabioshorbent[J/OL].BioresourceTechnology,2007,doi:10.1016/j.biortech.2007-05-23.[5].[J].,2007,26(3):20-22.[6].[J].,2003,36(3):51-53.[7]　,.[J].,2006,37(3):25-27.[8],.———[J].,2002,15(4):40-42.[9],.[J].,2006,9(3):48-50.[10]GAOP,CHENX,SHENF,etal.Removalofchromium(Ⅵ)fromwastewaterbycombinedelectrocoagulation-electroflotationwithoutafilter[J].SeparationandPurificationTechnology,2005,43:117-123.(:)·97·: