简介:Anincreasingnumberofannealingfurnaceshaverecentlybeenusingcheaperandcleanernaturalgas(NG)insteadofliquefiedpetroleumgas(LPG)asfuelgas.However,thefuelgasofthefurnacesoftenneedstobechangedwhenNGsupplyisnotadequateorwhenLPGbecomescheaper.Usually,changingthefuelgasinvolveschangingvariousequipmentaswellascontrolparametersforinstrumentsandthecontrolsystemandhenceistimeconsuming.Therefore,itisimportanttodevelopaquickprocessforchangingfuelgas.Thisstudydiscussesthetechniquesforquicklychangingfuelgasinanannealingfurnace.Thesetechniquesdealwiththedesignofthepipe,valveandburner,theselectionoftheflowmeterandtheflowcontrolvalve,theswitchofthesoftwareandparametersforthecontrolsystem,aswellastheoperation,commissioningandhottestofthefurnacewhenthefuelgasischanged.Usingthesetechniques,itispossibletochangefuelgasin6h.
简介:Thelimestone-gypsumfluegasdesulfurization(FGD)processhasbecomethemostwidespreadprocessintheworldforsulfurremoval.Theswirl-et-absorbingwetlimestone-gypsumsinteringFGDtechnologywasdevelopedforsinteringfluegasdesulfurization,andthisprocessproducesvolumesofwastewaterwithvariouscontaminantsthatrequirestreatmentbeforedisposalorreuse.Inthisstudy,thewastewaterqualityfromthreedifferentsinteringFGDsystemsatBaosteelGroupwasinvestigatedandcomparedwithwastewaterfrompowerplantFGD.AtreatmentprocesswasproposedwhichissuitableforsinteringFGDwastewater.Aftertreatmentwithaneutralization,coagulationandsedimentationprocess,heavymetalsinthesinteringFGDwastewaterwerereducedtoalevelmeetingtherelevantemissionstandards,butthepHandammoniaconcentrationweretoohigh,andafurthertreatmentprocesswasneeded.DuetocertainsimilaritiesandcomplementaritiesbetweensinteringFGDwastewaterandcokingwastewater,itisentirelyfeasibletomixthepretreatedsinteringFGDwastewaterintoabiologicalcokingwastewatertreatmentsystem.ThisstudyindicatesthatitisentirelyfeasibletomixpretreatedsinteringFGDwastewaterintothebiologicaltreatmentsystemsusedforcokingwastewaterfromtheironandsteelindustries.
简介:TheAODisbyitsverynatureandpurposealargegeneratorofCO2.ThetotalCO2emissionfromtheprocesscanbedividedintotwoparts-thedirectpartwhichisproportionaltothecarbonremovalfromthemetalandtheindirectpartwhichisrelatedtotheconsumptionofadditivessuchasreductionagents,slagformersandalloys.TheproductionoftheadditivestypicallyrequiredforaheatcauseslargeemissionsofCO2,infact,oftenlargerthanwhatisgeneratedfromthedirectpart.Byapplyingareal-timeadaptiveoptimizationoftheoxygentoinertgasratiooversmalltimeincrements,theoverallcarbonremovalefficiencyisincreasedwhiletheconsumptionofreductionagentsandslagformersaredecreased.ThisremovesunnecessaryproductioncostsandminimizesthetotalemissionofCO2.Inthispaperaprocessconceptwithoptimizedgasadministrationoveralargenumberoftimeincrementsiscomparedwithamoretraditionalprocesspractice.TheworkisbasedonindustriallyprovenprocessmodelsintegratedintheUTCASsoftwarepackageforconvertermanagementandcontrol.Finally,thispaperconcludesonhowthesuggestedprocesscanbeappliedinactualplantoperation.
简介:Thispapershallshowaneconomicfeasibleapproachtoimplementgreenhousegas(GHG)reductionmeasuresintosteelcompanies.ThegoaltoimproveenergyconsumptionisdirectlylinkedtothereductionofGHGemissionsandthereforedirectlyincorrelationwiththeeconomicviability.Abaselinescenariooftheconsideredreferencesystemandoftherespectivereferenceyearhastobedefined,mappedandanalysed.Inasecondstepananalysisofthesameoperationusingavailableandprospectedbestavailabletechnology(BAT)processesiscarriedouttogenerateabasisforabenchmarksystem.TheidentifiedreductionpotentialsarereportedandtheGHGemissionreductionsareputintorelationtotheinvestmentcostofthenewprocesstechnologies/processadaptiontobeimplemented.ThiseconomicfeasibilitycalculationisnecessarytorealiseacostefficientGHGreductionroadmapimplementationintothecompany’sbusinessoperations.TheGHGreductionroadmapisdevelopedusingtheabatementcurveconcepttogetanindicationof'lowhangingfruits'andforestablishingasequenceforimplementingcarbonemissionreductionsmeasures.ThescopeofthatapproachcanbeextendedbyincludingfurtherimportantenvironmentalparameterslikeNOx,SO2,CO,dust,heavymetalemissionsinairaswellasproductionresidues.ThatgivesintheendabroaderpictureandmorestartingpointstoimprovetheoverallenvironmentalperformanceofsteelproducingcompaniesbeyondtheGHGemissionsandenergyconsumption.
简介:TheresearchbackgroundandtechnicalfeaturesofBaosteelsinteringfluegasdesulphurization(FGD)—swirl-jet-absorbingwetlimestone-gypsumsinteringFGDtechnology,processandequipmentareintroducedinthispaper.MaincontentsandachievementsofthepilotexperimentandtheengineeringpracticeofBaosteelFGDareanalyzedanddiscussedsystematically.PastengineeringpracticeexperiencesindicatethatBaosteelFGDhasthefollowingmerits:wideapplicabilitytosinteringfluegasfeatures,suchasfrequentlychangingtemperatures,unstableSO2concentration,intensivelyfluctuatingflowrates,etc.,highpollutantsremovalefficiency,lowinvestmentandenergyconsumption;stableandreliableoperation,utilizablebyproduct(gypsum),etc.ItindicatesthatBaosteelsinteringFGDisofextensiveapplicationvaluefortheFGDoflargeandmedium-scaledsinteringmachines.
简介:Becauseofthelowtemperature,largewastegasvolume,highpollutantcontent,andcomplicatedcompositions,wasteheatrecoveryandemissiongastreatmentofsinteringfluegashavealwayspresentedachallengeinthesteelindustry,andthisissuehasattractedwidespreadattentionbothlocallyandabroad.Recently,basedonthefirstdomesticpilotplantanddemonstrationproject,Baosteelhasperformedaseriesofinnovativeresearchanddevelopmentinvestigationsonitssinteringfluegasrecirculating(SFGR)process,inwhichthesystemdesignandoptimization,dioxin-relatedcontaminantsourcesuppression,orematchingstructureoptimization,wear-resistantdesignofcyclingfansandpipelines,high-efficiencydustremovalequipment,systemcontrolandstableoperationstrategy,fluegasmixingandswitchingcontrol,circularhoodsealing,oxygencontentconditioning,recirculationsinteringsystemprocesscontrol,andmodeldevelopmenthavebeenstudied,andacompletesetofequipmentandtechnologyfortheSFGRprocesshasbeeninitiallydeveloped.TheinvestigationresultssuggestthattheSFGRprocesscannotonlysignificantlyreduceexhaustgasvolumeandpollutantemissionsbutalsorecoverlow-temperaturewasteheatandreducetheenergyconsumptionofsintering;therefore,theoveralltechnologiespossessgreatvalueinenergysavings,pollutionemissionreduction,andsinteringorequality/yieldimprovement.
简介:Thecharacteristicsofthedesulphurizedgypsumproducedinthefluegasdesulphurization(FGD)processoftheBaosteelsinteringplantareinvestigatedinthisstudy.Accordingtothetechnicalandqualityrequirementsofgypsuminthecementindustry,thefeasibilityofusingdesulphurizedgypsumasacementretarderisalsostudied.Theresultsshowthatdesulphurizedgypsumcanbeusedasacementretarderinsteadofnaturalgypsum.
简介:Inthisstudy,theeffectsofstandoffdistance(SoD)onthesupersonicflowfields(includinggasandparticleflowfields)duringcoldgasdynamicspraying(CGDS)areinvestigatedbymeansofcomputationalfluiddynamics(CFD).Thevariationofvelocity,temperature,pressureanddensitywithdifferentSoDiselucidatedthroughtheanalysisofthedistributionpropertiesoftheflowfields.Itisfoundthattheshockwavesinfrontofthesubstrateremarkablyinfluencethegasandparticleflowfields.Thewavesystemofexpansionwavesandpressurewavescomeintobeingcontinuously.ThevelocityofgasreachesthesupersonicspeedatthepositionoftheMachdisc,whileitdecreasessharplywhenthegasflowcrossestheMachdisc.TheoptimalSoDsare40mmfor1μmparticlesand50mmforboth5μmand22μmparticles.
简介:Thedifferencesofreductionbehaviorsbetweenironorelumpandpelletswerestudiedbyconductinglowtemperaturereductiondegradation,staticloadreductionanddroplettests.Thesetestssimulatedtheconditionsofreductiontemperatureandhydrogen-containinggasinCOREX.Duetoitsdensestructureandlowporositycomparedwithpellets,lumporepossessespoorreductiondegradationindex(RDI)andslowerreductionrateinearlyandmediumreactionstages,showingsignsoflowerstrength,lowersofteningandmeltingtemperatures,aswellasawidermeltingzoneandhigherΔP.Thatprovidessomebasistoexplainthephenomenaofdifferentialpressurerise,metallizationdeclineandmorestickingaftertheusageoflumporeinCOREXplant.
简介:Withanalloycontentashighas80%ormore,Ni-basedOCTGisastrategicproductsrelatedtothestateenergysecurity,mainlyappliedintheexploitationanddevelopmentofsourgasfieldswithcomplicategeologicalformation,hightemperature,highpressureandseverecorrosivewellconditions.Ni-basedOCTGisregardedasthepipeproductwithmosthightechnologiesduetothecomplexityandgreatdifficultyinmanufacturingandrigorousrequirementsinqualitycontrol.Inthispaper,thetechnicalfeaturesandqualityrequirementsofNi-basedOCTGaresummarized,andthequalityandpropertiesoftheNi-basedOCTGproductsofBaosteelareintroducedindetail.WiththehelpofSEM,XPSandTEM,thecorrosionmechanismofNickle-basedOCTGintheenvironmentscontainingH2S,CO2,Cl-andelementarysuifurarealsoanalyzed.
简介:Inconel718superalloycoatingwaspreparedonamartensiticsteelsubstratebycoldgasdynamicspraying(CGDS).Microstructureandmicro-hardnessofthecoatingwerecharacterizedbymeansofscanningelectronicmicroscope(SEM),energydispersivespectrometer(EDS),andmicro-hardnessandnano-indentationtests.Theresultshaveindicatedthatthecoating’sthicknesscanreachmorethan300μm,andthereexistsagoodinterfacialcohesionbetweenthecoatingandthesubstrate.Thequantityandsizeofthedefectsatthebottom,middleandtopareasincreasegradually.ThereisnosignificantchangetotheoriginalmicrostructureoftheInconel718superalloyparticleaftertheprocessofCGDS;andanobvioustorsionaldeformationontheparticle’sprofileisproducedwhilelittledeformationatthecenterpartoccurs.Themicro-hardnessofthecoatingatthebottom,middleandtopareasdecreasesinturn.Comparedwiththebottomarea,themicro-hardnessofthemiddleandtopareasdecreasesbyabout10%and21%,respectively.Thenano-hardnessofthecoatingismuchlowerthantheoriginalparticle,whichdecreasesbyabout13.5%atthebottomareaand28%atthetoparea,respectively.Thedistributionofmicro-defectsisanimportantfactortothemicro-hardnessofthecoating.
简介:Theeffectsofthesubstratetemperatureonthedepositionandmicrostructureofthe304stainlesssteel(SS)coldgasdynamicspraying(CGDS)coatingswereinvestigated.Itwasfoundthatthehighersubstratetemperaturecouldincreasethedepositionrateofthe304SSparticles,eventheoxidefilmsexistedattheinterface.Therewasacriticaloxidefilmwithathicknessof3-4μmwhichcouldbedestroyedbytheimpactedparticles.Themicro-hardnessandmicrostructureofthe304SScoatingsunderdifferentsubstratepreheatingtemperatureswerealmostthesame.