超滤操作条件对超滤膜清洗效率的影响

:1007-8924(2006)01-0047-04超滤操作条件对超滤膜清洗效率的影响齐希光1郭群峰2李秀芬3*(1.,214036;2.,063000;3.,,214036):超滤操作条件直接影响膜面滤饼层的厚度和密度,从而间接影响污染膜的化学清洗效率.针对聚砜超滤膜-谷氨酸发酵液体系,着重考察超滤溶液pH值离子强度污染时间以及超滤压力对清洗效率的影响.结果表明,超滤pH值从2.77升高到7.00时,清洗效率升高到99.48%;但pH值进一步升高到9.00时,发酵液中的菌体和蛋白质及膜表面均带强大负电荷,由于静电排斥使得清洗剂中的有效成分阴离子表面活性剂难以接近污染层,清洗效率降低,从pH7.00的99.48%降低到pH9.00的82.71%;超滤时间越长,剪切力的作用使膜面滤饼越致密,清洗变得困难,超滤1h的清洗效率为99.73%,而3h的清洗效率为57.92%;超滤压力为0.05MPa时清洗效率为86.49%,压力升高到0.08MPa时,清洗效率达99.48%,即低压范围内,超滤压力大,清洗效率高;清洗效率随超滤溶液离子强度增大而增大.:超滤;发酵液;化学清洗:TQ028.8:A,.[1][2,3][4],,.50%,30%[5],.,,,,.1材料与方法1.1:,.pH6.8~7.2,34~36,,:3%~4%,7%~8%,1%,0.8%,0.6%~0.8%,0.6%~0.8%,.,1.425cm,34.68cm2,,,20000~30000,.1.22.J0,()24h,2L,,,.1%NaOH:2004-05-18;:2004-06-28:(1968-),,,.*[e-mail]261Vol.26No.120062MEMBRANESCIENCEANDTECHNOLOGYFeb.20061Fig.1SchematicdiagramofUFsystem,,0.3%1.5LUltrasil11(),20min,,1.5L,Jc.0.02MPa,.2Fig.2Flowsheetofmembranefoulingandcleaning,(rc)(,0.08MPa)(,)Jc(Lm-2h-1)J0(Lm-2h-1):rc=JcJ0100%(1)2实验结果与讨论2.1pHpH,[6].pH3.3Fig.3Cleaningefficiencyoffouledmembraneunderdifferentsolutionchemistryconditions,,pH9.00,pH,pH7.0099.48%,,,,,,;pH2.777.00,()(),,,,,,;pH,,,,,,,,82.71%.3:,,,,,,,;,,,,,.2.20.3%NaOH+0.3%H2O2,45.4.,,1h99.73%2h57.92%.,4826,,,,.4Fig.4CleaningefficiencyofdifferentUFtime2.3,,,[7],.,0.050.08MPa,,0.05MPa,86.49%,0.08MPa99.48%.,,0.050.08MPa,10.3910-121.5410-12m-1,,.Ramesh[8]:,,,.,,,[9].,,,,,,,.Bartlett[10],,,,,,,,,,.3结论.pH7.00,pH,,,,,,,pH2.7783.10%7.0099.48%,pH9.00,82.71%;,;,,;,.[1]KuruzovichJN,PiergiovanniPR.Yeastcellmicrofiltra-tion:optimizationofbackwashingfordelicatemembranes[J].JMembrSci,1996,112:241-247.[2]MaH,HakimLF,BowmanCN,etal.Factorsaffectingmembranefoulingreductionbysurfacemodificationandbackpulsing[J].JMembrSci,2001,189:255-270.[3]MoresWD,DavisRH.Directvisualobservationofyeastdepositionandremovalduringmicrofiltration[J].JMembrSci,2001,189:217-230.[4]MaH,BowmanCN,DavisRH.Membranefoulingre-ductionbybackpulsingandsurfacemodification[J].JMembrSci,2000,173:191-200.[5]TamC,Dal-CinM,CapesetalE.Importantconsidera-tionsintheselectionanduseofmembraneseparationpro-cesses[J].ProcessTechnolProc,1994,11:681-701.[6]KinsellaJE,WhiteheadDM.Proteinsinwheychemicalphysicalandfunctionalproperties[J].AdvFoodNutritionRes,1989,33:343-438.[7]BurrellKJ,GillC,McKechnieMT,etal.Advanceinseparationtechnologyforthebrewer:ceramiccross-flowmicrofiltrationofroughbeer[J].MBAATechnicalQuar-terly,1994,31(2):42-50.[8]RameshBP,GaikarVG.MembranecharacteristicsasdeterminationinfoulingofUFmembranes[J].SepnPu-rifnTechnol,2001,24:23-34.[9]FoleyG,MaloneDM,MacloughlinF.Modelingtheef-fectsofparticlepolydispersityincrossflowfiltration[J].JMembrSci,1995,99:77-88.[10]BartlettM,BirdMR,HowellJA.Anexperimentalstudyforthedevelopmentofaqualitativemembranecleaningmodel[J].JMembrSci,1995,105:147-157.(54)1:49[1],,.[J].,2003,23(6):54-58.[2],.[J].,1999,19(4):1-11.[3],,.[J].,2000,20(11):10-13.[4],,.[J].,2002,28(1):12-16.[5]PlummerMA,ColoL.Preventingpluggingbyinsolublesaltsinahydrocarbon-bearingformationandassociatedproductionwells[P].USPat:4723603,1988-02-09.[6]WilfM,ChebtP,LangeP.Designandperformanceofalargereverseosmosissoftingplan[A].IDAConference[C].Washongton:1991.1-25.[7]HassanAM,Al-SofiMAK,Al-AmoudiAS.Anewapproachtomembraneandthermalseawaterdesalinationprocessesusingnanofiltrationmembranes(Part1)[J].De-salination,1998,118(1-3):35-51.[8],.[J].,2000,26(5):223-258.[9],,.[J].,2002,16(3):257-262.[10],.[J].,2002,18(9):45-46.[11],,.[M].:,2001.6-10.[12],,,.[M].:,2001.248-250.[13].[M].:,2003.38-73.StudyondesalinationperformanceofseawaterwithnanofiltrationmembraneFANGJianhui,JIANGHua,LIUJiquan,SHENXia,ShiLiyi(DepartmentofChemistry,ShanghaiUniversity,Shanghai200444,China)Abstract:Seawaterdesalination,amajortechnologyforsolvingtheproblemofwatershortage,hasnotbeenwidelyacceptedovertheworldjustbecauseofitshighenergyandinvestment.Desalinationexperimentsofsea-waterwerecarriedoutbyusingHL1812nanofiltrationmembrane.TheeffectsoftheDesalinationtimeandthetemperatureofseawateraswellasthepressureontheseparationperformanceandstabilityofnanofiltrationmembranewereinvestigated.Lowercostcanbeobtainedbyutilizingnanofiltrationasapretreatmentforthere-movalofhardnessandTDS.Keywords:membraneseparation;nanofiltration;seawaterdesalination(49)EffectofUFoperatingconditiononcleaningefficiencyoffouledmembraneQiXiguang1,GUOQunfeng2,LIXiufen3*(1.SchoolofFoodScience,SouthernYangtzeUniversity,Wuxi214036,China;2.NorthChinaCoalMadicalInstitute,Tangshan063000,China;3.KeyLab.ofIndustrialBiotechnology,MinistryofEducation,SchoolofBiotechnology,SouthernYangtzeUniversity,Wuxi214036,China)Abstract:UFoperatingconditionsdirectlyinfluencethethicknessanddensityofcakelayeronthemembranesurfaceandindirectlythecleaningefficiencyoffoulingmembrane.TheeffectoffeedpH,ionicstrength,foulingtimeandpressureonthecleaningefficiencyduringthefiltrationofglutamicfermentationbrothisinvestigated.Theresultsshowedthatthecleaningefficiencyisupto99.48%withpHincreasingfrom2.77to7.00.Howev-er,thecleaningefficiencyfallsto82.71%atpH9.00becausethestrongrepulsionoccursbetweenthenegativesolv