城市污水處理技術(shù)

Urbansewagetreatmenttechnology(EnglishcoursewREPORTING目錄introductionOverviewofUrbanSewageTreatmentTechnologyPhysicalprocessingtechnologyBiochemicaltreatmenttechnologyDeepprocessingtechnologySludgetreatmentanddisposalOperationandmanagementofurbansewagetreatmentplantsPART01introductionREPORTINGResidentialwastewater01Comingfromresidentialareas,containingdetergents,soaps,andotherpollutants.Commercialwastewater02Generatedfromcommercialactivities,includingrestaurants,hotels,hospitals,etc.Itcontainsgrease,oil,andotherpollutants.Industrialwastewater03Generatedfromindustrialproductionprocesses,containingavarietyofpollutantssuchassuspendedsolids,dissolvedsolids,heavymetals,andorganicmatter.TheSourceofUrbanSewage03WaterreuseTreatingurbansewagecanmakewatercleanandsafeforreuseinirrigation,industrialcooling,andotherpurposes.01EnvironmentalprotectionTreatingurbansewagecanreducethepollutionofwaterbodiesandprotecttheecologicalenvironment.02PublichealthTreatingurbansewagecanremovepathogenicbacteriaandviruses,reducingtheriskofwater-bornediseases.TheNecessityofUrbanSewageTreatmentPART02OverviewofUrbanSewageTreatmentTechnologyREPORTINGRemovaloflargesolidsandfloatingdebrisfromrawsewage.InletPretreatmentSedimentationofheaviersolidstoremoveabout30%oftheorganicmatter.PrimaryTreatmentBiologicaltreatmentusingmicroorganismstoconsumeorganicmatterandconvertitintoharmlessby-products.SecondaryTreatmentAdditionaltreatmentstepsthatmayincludefiltration,disinfection,andnutrientremoval.TertiaryTreatmentTheBasicProcessofSewageTreatmentTheMainMethodsofSewageTreatmentConventionalSewageTreatmentTypicalprimaryandsecondarytreatmentmethods.AdvancedSewageTreatment(AST)Enhancedmethodsthatprovidebettereffluentquality,includingnutrientremovalanddisinfection.PhytoremediationUseofplantsandtheirassociatedmicroorganismsforwaterpurification.ConstructedWetlandsSimulatednaturalwetlandsforwastewatertreatment.Meetingdischargelimitsandeffluentstandards.RegulatoryRequirementsCostEnergyConsumptionEnvironmentalImpactCapitalandoperationalcostsofthetechnology.Theamountofenergyrequiredfortheoperationofthetreatmentsystem.Theimpactontheenvironmentduringoperation,sludgedisposal,andwaterreusepotential.SelectionCriteriaforSewageTreatmentTechnologyPART03PhysicalprocessingtechnologyREPORTINGSedimentationBasicsSedimentationisanaturalprocessinwhichsolidparticlesinwatersettletothebottom.Thistechnologyusesthisprincipletoremovesolidsfromwastewater.AdvantagesSimpleandcost-effective.Itcanhandlelargevolumesofwater.DisadvantagesEfficiencydependsonparticlesizeanddensity,andmaynotremoveallsuspendedsolids.SedimentationTechnologyFiltrationusesaporousmediumtotrapparticles,removingsolidsandsomedissolvedpollutants.FiltrationPrinciplesIncludesandfiltration,membranefiltration(microfiltration,ultrafiltration,nanofiltration,reverseosmosis).TypesofFiltrationPrimarilyusedfordrinkingwatertreatmentandindustrialwastewater.ApplicationsFiltrationTechnologySeparationMethodsIncludeflotation,electrocoagulation,andcentrifugation.FlotationAprocessinwhichairbubblesattachtosuspendedparticles,liftingthemtothesurfacewheretheycanberemoved.ElectrocoagulationUseselectricitytocreatechargedparticlesthatcoagulatewithpollutants,causingthemtosettleorfloatforremoval.CentrifugationUsescentrifugalforcetoseparatesuspendedsolidsfromwater.SeparationTechnologyPART04BiochemicaltreatmenttechnologyREPORTING總結(jié)詞Theactivatedsludgeprocessisacommonmethodoftreatingwastewater,usingmicroorganismstobreakdownorganicmatter.詳細(xì)描述Intheactivatedsludgeprocess,wastewaterismixedwithmicroorganismsandair,formingasuspensionofmicroorganismscalled"activatedsludge".Themicroorganismsconsumetheorganicmatterinthewastewater,convertingitintocarbondioxide,water,andnewmicroorganisms.Theactivatedsludgeisthenseparatedfromthecleanedwater.ActivatedSludgeProcess總結(jié)詞Thebiofilmmethodinvolvestheuseoffixedbiofilmstotreatwastewater.要點(diǎn)一要點(diǎn)二詳細(xì)描述Inthebiofilmmethod,microorganismsattachtosurfacesinareactorandformabiofilm.Thewastewaterflowsthroughthereactor,andthemicroorganismsinthebiofilmconsumetheorganicmatterinthewastewater.Thecleanedwateristhendischarged,whilethebiofilmremainsattachedtothereactorsurface.BiofilmMethod總結(jié)詞Theanaerobicbiologicaltreatmenttechnologyusesanaerobicmicroorganismstobreakdownorganicmatterinwastewater.詳細(xì)描述Intheanaerobicbiologicaltreatmenttechnology,thewastewaterismixedwithanaerobicmicroorganismsinananaerobicreactor.Themicroorganismsbreakdowntheorganicmatterinthewastewaterintomethane,carbondioxide,andotherbyproducts.Thecleanedwateristhendischarged,andthemethanecanberecoveredforenergyuse.AnaerobicBiologicalTreatmentTechnologyPART05DeepprocessingtechnologyREPORTINGSummary:Disinfectiontreatmentisessentialtoeliminatepathogenicmicroorganismsandensurewaterquality.DisinfectionTreatmentDetailsCommondisinfectionmethodsincludechlorination,ozonation,andUVirradiation.Chlorinationisthemostwidelyusedmethod,butitmayproduceharmfulbyproducts.DisinfectionTreatmentDisinfectionTreatmentOzonationiseffectiveagainstawiderangeofmicroorganisms,butitisexpensive.UVirradiationisaphysicalmethodthatdoesnotproduceharmfulbyproducts,butitrequiresahighinitialinvestment.Summary:Removingnitrogenandphosphorusiscrucialtoreduceeutrophicationandimprovewaterquality.NitrogenandPhosphorusRemovalTechnologyDetailsPhosphoruscanberemovedbychemicalprecipitationorbiologicalremovalmethods.Chemicalprecipitationinvolvesaddinglimeoralumtoprecipitatephosphorus,whilebiologicalremovalusesmicroorganismstoabsorbanddegradephosphorus.Denitrificationisacommonmethodtoremovenitrogen,usinganaerobicbacteriatoconvertnitrateintonitrogengas.NitrogenandPhosphorusRemovalTechnologySummary:Advancedoxidationtechnologyisusedtodegraderefractoryorganicpollutantsandremoveharmfulsubstances.AdvancedOxidationTechnologyDetailsAdvancedoxidationprocessesincludeozonation,UV/H2O2,andphotoelectrochemicaloxidation.Ozonationcandegradeorganicpollutants,butitmayproduceharmfulbyproducts.AdvancedOxidationTechnologyUV/H2O2usesUVlightandhydrogenperoxidetogeneratehydroxylradicalsforoxidation,butitrequiresahighenergyinput.Photoelectrochemicaloxidationusessemiconductorstogenerateelectronsandholesforoxidationandreductionreactions,respectively.AdvancedOxidationTechnologyPART06SludgetreatmentanddisposalREPORTINGSludgeisaby-productofwastewatertreatmentprocesses,mainlycomposedoforganicmatter,suspendedsolids,andmicroorganisms.Thecharacteristicsofsludgevarydependingonthesourceofthewastewaterandthetreatmentprocessused.Sludgemaycontainpathogenicbacteria,viruses,heavymetals,andotherharmfulsubstances.TheSourceandCharacteristicsofSludgeTreatmentMethodsforSludgeThismethodinvolvesseparationofsolidandliquidfractions,thickening,dewatering,andstabilizationofthesludge.ChemicaltreatmentTheuseofchemicalssuchaslime,ferricchloride,orpolymerstoimprovesludgesettling,dewatering,andstabilization.BiologicaltreatmentThismethodusesmicroorganismstodegradeorganicmatterinthesludge,reducingitsvolumeandimprovingitsstability.Physicaltreatment要點(diǎn)三LandfilldisposalThesludgeistransportedtoalandfillsitefordisposal.Thismethodis簡(jiǎn)便，butmaycausepollutionandodorproblems.要點(diǎn)一要點(diǎn)二AgriculturalutilizationThesludgeisappliedtofarmlandasafertilizer,providingnutrientstoplants.However,thesludgemustbewell-treatedtoensuresafety.ThermaldisposalThesludgeisincineratedathightemperaturestodestroyorganicmatterandreducethevolumeofthesludge.Thismethodrequiresahighenergyinputandmayemitharmfulgases.要點(diǎn)三DisposalandUtilizationofSludgePART07OperationandmanagementofurbansewagetreatmentplantsREPORTINGCentralizedTreatmentThismodeinvolvesthecollectionofsewagefromvarioussources,transportingittoacentrallocation,andtreatingitthere.Itisthemostcommonmodeandsuitablefordenseurbanareas.DecentralizedTreatmentAlsoknownason-sitetreatment,thismodetreatssewageatitssource,usuallyindividualdwellingsorsmallcommunities.Itissuitableforscattereddwellingsorremoteareas.CombinedTreatmentThismodecombinescentralizedanddecentralizedtreatment.Itissuitableforlargeurbanareaswherebothcentralizedanddecentralizedsewagetreatmentplantsarerequired.OperationModeofSewageTreatmentPlantEnergy-savingEquipmentUsingenergy-efficientequipmentsuchaspumps,blowers,andmixerscanreduceenergyconsumption.Theuseofbiologicalprocessesinsewagetreatmentcanreduceenergyrequirementscomparedtophysicalorchemicalprocesses.Capturingenergyfrom