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华北水利水电学院硕士学位论文新型超滤膜水处理性能及膜污染规律研究姓名：刘纳申请学位级别：硕士专业：环境工程指导教师：黄健平2011-04华北水利水电学院硕士学位论文I新型超滤膜水处理性能及膜污染规律研究摘要膜法水处理技术是一种新型的污水处理技术。在水资源缺乏和水污染日益严重的今天，该技术显示出强大的生命力而倍受青睐，成为废水处理与资源化的关键技术之一。本论文将自制的新型超滤平板膜和五孔中空纤维膜组件应用于城市污水处理，考察其处理效果、膜污染和再生性能。主要结果如下：(1)采用污水处理厂二沉池出水作为超滤膜的进水，研究以超分子β-CD为添加剂制备的PVDF/PMMA、PES超滤平板膜及商品PES平板膜的处理效果、污染性能和再生方法。结果表明平板膜的出水均比较稳定，达到了回用水的水质要求。PES商品膜和PES膜的运行初期膜通量下降较快，后期逐渐趋于稳定；以1.5h为界限，把过滤过程分为两个阶段，第І阶段符合膜孔堵塞模型，第Π阶段符合沉积层阻力模型；PES商品膜、PES膜清洗的结果表明在本实验中反冲洗效果较差，H2O2浸泡效果良好。清洗后膜的通量恢复率均在90%以上，膜的再生性能良好。相比之下PVDF共混膜的通量一直处于较稳定状态，运行时间超出PES膜约5倍时仍不需要清洗，表明改性后的PVDF膜亲水性良好，膜污染较轻。(2)采用自制的两种不同共混材料PVDF膜(PVDF/PMMA/TPU膜(膜组件A)和PVDF/PMMA/PVC膜(膜组件B))，系统研究了膜处理城市污水的处理效果、膜污染性能和膜清洗特性。实验结果表明膜组件的出水水质参数均达到了《城市污水再生利用城市杂用水水质》(GB/T18920-2002)的要求。与传统处理工艺相比，省略了后续的混凝沉淀、砂滤、消毒工艺，彻底消除氯消毒产生的氯前驱物造成的危害。对膜污染控制研究，得出连续运行的方式膜污染昀严重；间歇运行方式的较佳抽停比为10min∶2min，延长抽停比可加剧膜污染，抽-反冲运行方式膜污染速率昀小。PVDF/PMMA/TPU共混改性膜对污染物的去除率比PVDF/PMMA/PVC共混改性膜的去除率稍华北水利水电学院硕士学位论文II高。实验表明PVDF/PMMA/TPU共混体系和PVDF/PMMA/PVC共混体系制备的五孔中空纤维膜具有优良的性能。通过膜阻力分析得出膜阻力主要为可逆阻力(浓差极化边界阻力)，可通过物理清洗的方法得到去除；其次为纯膜阻力；不可逆阻力(膜污染阻力)所占比例昀小；说明两种共混膜的抗污染性能较好。通过进一步的研究，得出高速水力冲洗+NaClO溶液浸泡是一种有效且省时的清洗方法。后续的研究也证实这种方法的有效性，膜通量恢复率达到90%以上。与膜组件B相比，膜组件A具有更好的抗污染性能，膜组件A运行周期是膜组件B运行周期的2倍以上。综上所述，PVDF共混改性膜在城市污水处理中具有一定的应用前景，新型超滤膜水处理性能的研究结果为新型耐污染水处理膜的应用提供参考。关键词：水处理，平板膜，五孔膜，膜污染，阻力分布，膜清洗华北水利水电学院硕士学位论文IIISTUDYONWASTEWATERTREATMENTPERFORMANCEANDMEMBRANEFOULINGOFNOVELULTRAFILTRATIONMEMBRANESAbstractMembraneprocessisanovelwastewatertreatmenttechnology.Thistechnologyhasrapiddevelopmentandawideconcernbecauseofwaterresourcedeficiencyandwaterqualitydeterioration.Membraneprocesshasbeenusedasakeytechnologyforwaterreclamationandreuseofwaterresource.Inthisdissertation,themembraneswereusedtotreatmunicipalwastewater,andtheeffluentquality,membranefoulingandcleaningpropertieswerestudied.Asaresult,thefollowingconclusionsweredrawn:(1)Themembraneswereusedtotreattheeffluentfromsedimentarytankofmunicipalwastewatertreatmentplant.Thewastewatertreatmentperformance,foulingcharacteristicsandregenerationcharacteristicsofPVDF/PMMA-β-CD,PES-β-CDcompositeplatultrafiltrationmembranesandPESplatcommercialmembranewereinvestigatedincomparableconditions.Theresultsshowedthattheeffluentcanmeetthedemandsofwaterreclamation.ThefluxdecreasedratiosofPEScommercialmembraneandPESmembranewerehighduringtheinitialperiodandtendedtostablyduringthelaterperiod.Tookthe1.5hfortheboundary,thefiltrationperiodwasdividedintotwoperiods.PeriodІwasfittothestandardblockingfiltrationmodelandperiodΠwasfittocakefiltrationmodel.TheresultsobtainedbycleaningmethodsofPEScommercialmembrane华北水利水电学院硕士学位论文IVandPESmembraneshowedthatbackwashhaslittleeffectonmembranepermeabilityrecovery,andH2O2soakingiseffectivetorecovermembranepermeability.ComparedwithPEScommercialmembraneandPESmembrane,thefluxofPVDFmembranewasinastablestate,theoperatingtimeofPVDFmembranewassixtimesasmuchasthatofPESmembranesandPVDFmembranedidn’tneedmembranecleaning.TheresultsshowedthatthehydrophilicityofthemodifiedPVDFmembranewasexcellentandmembranefoulingwasslightly.(2)TwodifferenttypesofcompositefiveborehollowfibermembranemoduleswhicharemoduleA(PVDF/PMMA/TPUblends)andmoduleB(PVDF/PMMA/PVCblends)inpresenceofthesamebiomassconcentrationwereappliedtoverifytheeffluentquality,foulingcharacteristicsfordomesticwastewatertreatment.Alltheresultsoftheexperimentswerecompliedwithstandardoftheeffluentdischargestandardstourbanmiscellaneouswaterconsumption(Reuseofrecyclingwaterforurban-Waterqualitystandardforurbanmiscellaneouswaterconsumption)(GB/T18920-2002).Thesystemproducedeffluentsequivalenttothoseofanoxidized,coagulated,clarified,filtered,anddisinfectionwastewaterandcouldreducefollowingtertiarytreatmentprocess,endangerofchlorineprecursorwascompletelyeliminated.Themethodofmitigatingmembranefoulingwasstudied.Theresultshowedthatthemoreseverefoulinghappenedduringtheconstantcondition.Theoptimumoperationconditionofintermittentfiltrationconditionofsuctiontime/suspended华北水利水电学院硕士学位论文Vtimeratiowas10min/2min,membranefoulingincreasedassuctiontime/suspendedtimeratioincreased,membranefoulingratereachedlowestduringsuction-backwashingcondition.ThePVDF/PMMA/TPUblendsdidalittlebetterthanthePVDF/PMMA/PVCblendsintermsofremovalefficiencies.TheresultsshowedthatPVDF/PMMA/TPUblendsandPVDF/PMMA/PVCblendspossesexcellentcharacteristics.Theresultoffoulingresistancespropensityshowedthatthereversiblefoulingresistances,whichwasproducedbyconcentrationpolarizationandcanberemovedbyphysicalcleaning,wasthemainmembraneresistance,thenwastheintrinsicmembraneresistance,andtheresistancecausedbysoluteadsorptionintothemembraneporesandwallwastheleast.Theanti-foulingcharacteristicsofmembraneswereexcellent.Bymeasuringthefluxofmembraneandcleaningmembranemoduleofdifferentmethods,itwasfoundedthatwashoutbywaterandsoakinginNaClOsolutionwaseffectiveincontrolblendmembranemodulepollution.Thelatterstudyalsoverifytheconclusionandthemembranefluxrecoverieswereoverthan90%.ComparedwiththemoduleB,themoduleAhadbetteranti-foulingcharacteristics,theoperatingtimeofmoduleAwastwiceasmuchasthatofmoduleB.Inconclusion,themodifiedPV