DieselSystemsDenoxtronic2.2–UreaDosingSystemforSCRSystemsTomeettheworld’sstrictestlimitsfornitrogen-oxideemissionsinthefuture,efficientexhaust-gastreatmentsystemsaremandatory.WithourDenoxtronicforcommercialvehicles,weintroducedsuchasystemtothemarketaslongagoas2004.Itwasagreatsuccessandin2008wonthe“EcoGlobe”environmentprizeinthecategoryof“supplierinnovation”.Seriesproduc-tionofthethirdgenerationDenoxtronic2.2startedinlate2009forseveralcustomers.AnintegratedpumpintheSupplyModuleoftheDenoxtronicfeedsthereductionagentAdBlue/DEF(a32.5-percentsolutionofureainwater)fromthetanktotheDosingModule.ThisinjectstheAdBlue/DEFdirectlyintotheflowofexhaustgasupstreamoftheSCR(SelectiveCatalyticReduction)catalyticconverter.Theureaisthenconvertedviahydrolysisintoammoniarequiredforthefurtherreaction.Inthesecondstep,insidetheSCRcatalyticconverter,theammoniareducestheexhaust-gasnitrogenoxidesintoharmlesswaterandnitrogen.Theelectroniccontrolcanbeintegratedintotheenginecontrolunit(ECU)or,alternatively,intoaDosingControlUnit(DCU).ThecontrolunitmatchestheamountofAdBlue/DEFpreciselytotherelevantengineparameters.InthiswayitispossibletoreduceNOxemissionsbyupto95%.PossibleapplicationsTheDenoxtronic2.2hasbeendesignedforuseintheheavy-andmedium-dutysegment.Today,itisalsosuccessfullyusedinoff-highwayapplications.CustomerbenefitsuReductionofnitrogen-oxideemissionsbyupto95%uSimplificationoromissionofinternalenginemeasuresforemissionreductionuImprovedefficiencyofthedieselengine(byaround3%)AdvantagesbyinnovationuModulardesignwithseparatecomponents–SupplyModule,DosingModuleandoptionalDosingControlUnit(DCU)–forflexibleadap-tationtovariouspackagingandinstallationsituationsuDosingcontrolbyclosedcircuitbasedonevaluationofuptotwoNOxsensorsuControloftwoBoschsystemswithoneDCU:Denoxtronic2.2andDepartronic(systemforparticulate-filterregeneration)uRealizationofsmalldosingquantitiesandnarrowdosingtolerancesuFineAdBlue/DEFatomizationu12or24VoperationuSupplyModuleheatedeitherelectricallyorbyenginecoolantuCoolingofDosingModulebyenginecoolantinsteadofAdBlue/DEFAdBlue/DEFtankSupplyModuleEDCcontrolunitTemp.sensorSCRcatalyticconverterActuatorsSensorsEngineCANDiagnosisCANTemp.sensorNOxsensorDosingControlUnit(optional)EnginecoolantlineInletlineLevelsensorTemp.sensorDosingModuleDenoxtronic2.2withenginecoolantheatingEnginecoolantforDosingModuleReturnlineRobertBoschGmbHDieselSystemsPostfach30022070442StuttgartGermanyFax:+49711811-45090diesel@bosch.com©RobertBoschGmbH2010.Allrightsreserved,alsoregardinganydisposal,exploitation,reproduction,editing,distribution,aswellasintheeventofapplicationsforindustrialpropertyrightsFunctionalprincipleTheSupplyModuledrawstheAdBlue/DEFoutofthetankwithadiaphragmpumpandcompressesittothesystempressureof9barrequiredforatomization.Thispressureispreciselymaintainedviathespeedoftheelectricdrivemotor.TheDosingModuledosesandatomizestherequiredquantityofAdBlue/DEF.Controlofthedosingandheatingstrategy,aswellasforon-boarddiagnosis,iscarriedoutbytheDosingControlUnit(DCU)oralternativelyasoftwaremoduleintheEngineControlUnit.Dependingonseveralinputsignals(e.g.NOxemission,engineload)thedosingstrategycalculatestherequireddosingquantityandconvertsthisintoapulse-width-modulatedsignalfortheDosingModule.Thesystemhasaclosedcontrolloop.AdBlue/DEFfreezesat-11°C.Thereforethesystemisemptiedatengineswitchoffandheatedbeforerestarttoprotectitfromfrostdamages.Dosingisstartedonlywhenthesystemisice-free.OutlookFutureDenoxtronicdevelopmentwillhavemanyfocusesincludingoptimizationofthespray,increasedrobustnesswhenthesystemfreezesandoptimizationforoff-highway-specificapplications.Anotherdevelop-menttargetisqualifyingtheDenoxtronicsoitcancontributetofulfillingfutureemissionstandardsinmarineapplications.DieselSystems|Denoxtronic2.2UreaDosingSystemforSCRSystemsTechnicalfeaturesDosingquantity(min./max.)36/7,200g/h@9barDropletsize≤75µmSauterMeanDiameterLifetimeEqualsB10:SupplyModule30,000hDosingModule24,000hDosingControlUnit30,000hStart/stopcycles100,000HeatingconceptElectricalorbyenginecoolantOperatingvoltage12V/24VInterfacesAdBlue/DEFPlasticSAEJ20443/8”and5/16”Electrical,SupplyModuleTYCO12pinElectrical,DosingModuleBoschcompactDimensionsDosingModuleLxWxH:100x60x110mmapprox.DimensionsSupplyModuleLxWxH:220x209x134mmapprox.InjectionlinebetweenDosingandSupplyModule:Length≤10mInnerdiameter3...6mmFieldsofapplicationMD,HD,OHWEmissiontargetEuroV/VI,US10,JPNLT,Tier4,Stage4Denoxtronic2.2componentsSupplyModuleDosingModuleDosingControlUnitBosch:BenefitfromourcompetencesComprehensiverangeofservicesandknow-howSystemandnetworkcompetenceInnovatorandtechnologyleaderWarrantorforqualityanddependabilityWorldwidepresenceUniversalpartner112233