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IronmakingProcessAlternativesScreeningStudyVolumeI: SummaryReport

SLURRYPIPELINE

CONCENTRATE

SLABSHIPPING

IRONOREMINE

OREBENEFICIATION CONCENTRATOR

SLURRYRECEIVING,

DEWATERING PELLETPLANT

NATURALGAS

NATURALGASPRODUCTION

DIRECTREDUCTION

PLANTS

PELLETSTOCKPILE

DRI

EAFMELTING

ELECTRICPOWER

(50%FROMCOAL,50%FROMN.G.)

SLABCASTER LMFs

STEELSLABS

ORETOCONCENTRATOR

TOPORT

VACUUMDEGASSING

October2000LGJobNo.010529.01


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DISCLAIMER

This report was prepared as an account of work sponsored by an agency of the United States

Government. Neither the United States Government nor any agency thereof, nor any of their

employees, makes any warranty, expressed or implied, or assumes any legal liability or responsibility

for the accuracy, completeness, or usefulness of any information, apparatus, product, or processdisclosed, or represents that its use would not infringe privately owned rights. Reference herein to any

specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise

does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United

States Government or any agency thereof. The views and opinions of authors expressed herein do not

necessarily state or reflect those of the United States Government or any agency thereof.


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Contents

VolumeI: IronmakingAlternativeStudyExecutiveSummary...............................................................................1StudyScopeandMethodology............................................................2IronmakingProcessDiscussionandGrouping................................3DiscussionofRankingAnalysis..........................................................4SummaryandConclusions..................................................................5

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ReportOutline

Section1: ExecutiveSummary1-1: GeneralDiscussion1-2: SummaryConclusions

Section2: StudyScopeandMethodology2-1: StudyScope

2-1.1 Introduction2-1.2 Scope/Objective

2-2: MethodologyandApproach2-2.1: IntroductiontotheMetSimProcessSimulator2-2.2: SimulationModelsofIronmakingProcesses2-2.3: SpreadsheetMassBalancesofProcessComponents2-2.4: SpreadsheetMassBalancesofIronmakingProcesses

2-3: BaseProcessLocation2-3.1: BaseLocationAssumptions2-3.2: LocationSensitivities

2-4: Process Capital (CAPEX) and Operating Cost (OPEX)Estimates2-4.1 ProcessCapitalCosts(CAPEX)2-4.2 ProcessOperatingCosts(OPEX)

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Section3:IronmakingProcessDiscussionandGrouping3-1: ProcessesConsideredandInitialScreening

3-1.1 ProcessesConsideredinInitialScreening3-1.2 ProcessScenariosSelected

3-2: ProcessDescriptions3-2.1 ShaftFurnaceProcesses3-2.2 RotaryKiln3-2.3 RotaryHearth3-2.4 FluidizedBed3-2.5 Other(Reactor,etc.)

3-3: ProcessGroupings3-3.1 GroupingByProductType3-3.2 GroupingByStageofCommercialDevelopment3-3.3 GroupingByIronUnitFeedMaterial3-3.4 GroupingByPrimaryReductantType3-3.5 GroupingByReductionProcessType3-3.6 GroupingByTargetNominalSizeofReduction

Unit/Train

Section4: DiscussionofRankingAnalysis4-1: RankingVariablesConsidered4-2: Sorting andRanking By CapitalCostEstimates(ThroughL.S.

Production)

4-3: Sorting andRanking By OperatingCost(OPEX)EstimatesThroughLiquidSteelProduction



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4-4: Sorting andRanking By OperatingCost(OPEX)EstimatesThroughIronUnitProduction

4-5: Sorting andRanking By Simple Internal Rate ofReturn(I.R.R.)4-6: SortingandRankingsByTotalElectricalPowerConsumptions4-7: Sorting andRanking By Cumulative ProcessGreenhouseGas

(AsCO2only)Emissions

4-8: SortingandRankingByTotalCumulative(IncludingElectricalPowerGenerationContribution)GreenhouseGasEmissions

4-9: WeightedRankingSummary(AllVariables)

Section5: SummaryandConclusions5-1: ConclusionsFromSorts

5-1.1 SortingonCapitalCostEstimates5-1.2 SortingonOperatingCostsforLiquidSteelProduction5-1.3 SortingonOperatingCostsforIronUnitProduction5-1.4 SortingonSimpleInternalRateofReturn(I.R.R.)5-1.5 SortingonTotalElectricPowerConsumption5-1.6 SortingonCumulativeProcess(only)Greenhouse Gas

(asCO2) Emissions

5-1.7 SortingonTotalCumulativeGreenhouseGas(asCO2)Emissions (Including Electrical Power GenerationContribution)



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5-2: ConclusionsFromRankingSorts5-2.1 RankingSortonEconomicVariables(1-4)5-2.2 RankingSortonEnergyandEnvironmentalVariables(5-7)5-2.3 RankingSortonAllVariables(1-7)

5-3: GeneralConclusionsFromSortingandRankingSums



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Section1: ExecutiveSummary1-1: GeneralDiscussionIron in theUnitedStates is largelyproducedfrom ironoremined in theUnitedStatesorimportedfromCanadaorSouthAmerica. Theironoreistypically smelted in Blast Furnaces that use primarily iron ore, ironconcentrate pellets metallurgical coke, limestone and lime as the rawmaterials. Under current operating scenarios, the iron produced fromthese Blast Furnaces is relatively inexpensive as compared to currentalternativeironsources,e.g.directironreduction,importedpigiron,etc.The primary problem the Blast Furnace Ironmaking approach is thatmany of these Blast furnaces are relatively small, as compared to thenewer, largerBlastFurnaces; thusare relativelycostly and inefficient tooperate. An additional problem is also that supplies of high-grademetallurgicalgradecokearebecoming increasingly in short supply andcostsarealsoincreasing.Inpartthisisduetotheshortsupplyandcostsofhigh-grade metallurgical coals, but also this is due to the increasingnecessityforenvironmentalcontrolsforcokeproduction.After year 2003 new regulations for coke product environmentalrequirementwill likelybe promulgated. It is likely that this alsowilleitherincreasethecostofhigh-qualitycokeproductionorwillreducetheavailabledomesticU.S.supply. Therefore,ironproductionintheUnitedStates utilizing the current, predominant Blast Furnace processwillbemorecostlyandwouldlikelybecurtailedduetoacokeshortage.Therefore, there isasignificantneed todeveloporextend theeconomicviability ofAlternate Ironmaking Processes to at least partially replacecurrentanddecliningblastfurnaceironsourcesandtoprovideincentivesfornewcapacityexpansion.

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Inthechartbelow,SteelmakingFeedMaterials(1999)aredenoted. Itcanbe seen that Hot Metal (primarily from Blast Furnaces) constitutesapproximately58%of theIronUnitFeed toSteelmaking. RecycledSteelScrapprovidesabout38%ofthefeedandDirectReducedIron(DRI)wasonly4%oftherawmaterialsforSteelmaking.

STEELMAKINGFEEDMATERIALS

SteelProduction(1999)Total788millionmetricton

4.1%

37.8%

57.7%

0.4%SCRAPDRIHOTMETALOTHER

The chart, Steelmakingby Process Type, summarizes the predominantSteelmakingprocessesusedintheworld. ThemajorityoftheSteel(60%)is produced by Oxygen reactor processes (i.e. BOF, QBOP, etc.).Following behind is the Electric Arc Process (EAF) with 33% and aresidualquantity(4%)bytheopenhearthprocess.

STEELMAKINGBYPROCESSTYPESteelProduction(1999)

Total788millionmetricton

60%

4% 3%33%

OXYGENELECTRICOPENHEARTHOTHER



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BasedonatotalnewIronUnitProduction,theoverwhelmingpercentage(92%) is either Blast Furnace Hot Metal or pig iron. A minoritypercentage (7%) is fromDirect Reduction Processes and thebalance isotherironsources.

IRONUNITPRODUCTIONIronProduction(1999)

Total583.61millionmetricton7%

92%

1%DRIPIGIRONOTHER

Of theAlternativeDirect Iron Reduction Processes, 67% of the DRI isproducedbytheMidrexShaftFurnaceDRIprocesses. Thesecond-mostproductionofDRI(23%)isbytheHYLSAprocesses. Thebalanceissplitbetween SL/RN (3%), Finmet (2%) andOther (predominatelyCorex at5%). ItissignificantthattheShaftFurnaceprocessesproducenearly90%ofthetotalAlternativeIronUnits.Although thereareanumberofAlternativeIronmakingProcesses in thestartup phase or development for commercial operation (e.g. Circored,Iron Carbide, the Rotary Hearth Processes, Tecnored, etc.), non as yetchallenge theShaftFurnaceProcesses. Oneof the constraints on theseShaftFurnaceprocessesisthattheyrequireeitherhigh-gradelumporeorpellets as their iron unit rawmaterial feed. Costs for such feeds aregoingupandtherearelimitationsinsupply.ThefineoreprocessesappeartopresentonepossibleavenueforeconomicAlternativeIronmakingProcessdevelopment. Thelowercostsofthefineores make the fluidized bed processes that utilize them potentially-attractivetargetsfordevelopment. Processeswherefineoreiscombinedwithlow-costcoalreduction(e.g.Tecnored, theRotaryHearthProcesses,



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etc.) also are potential Alternative Ironmaking processes that wouldwarrantfurtherdevelopment.

DRIPRODUCTIONBYPROCESSTYPEWorldDRIproductionbyProcess(1999)

Total38.61millionmetricton

2%

23%

0%

67%

3%5%

FINMETHYLIRONCARBIDEMIDREXSL/RNOTHER



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1-2: SummaryConclusionsThe primary conclusions of this comparative Study of AlternativeIronmakingProcessscenariosare: Theprocesseswith thebestcombinedeconomics (CAPEXandOPEXimpacts in the I.R.R. calculation)canbegrouped into thoseFineOrebasedprocesseswithnoscrapchargeandthoseproducingHotMetalforchargetotheEAF.

Apronouncedsensitivity toSteelScrapCostwas felt lessby theHotMetalProcessesandtheFineOreProcessesthattypicallydonotutilizemuchpurchasedscrap.

Intermsofevolvingprocesses,theTecnoredProcess(andinparticular,the lower-operating cost process with integral co-generation ofelectricalpower)wasinthemostfavorablegroupingsatallscrapcostsensitivities.

It shouldbenoted also that theConventional Blast Furnace processutilizingNon-Recoverycoke (froma continuous cokingprocesswithintegral co-generation of electricalpower) and the lower-capital costMiniBlastFurnacealsoshowed favorableRelativeEconomics for thelowandmedianScrapCostsensitivities.

The lower-cost, more efficientMauMee Rotary Hearth Process thatusesaBriquettedIronUnitFeed(insteadofadriedorinduratedironorepellet)alsowasinthemostfavorableprocessgroupings.

Thoseprocesseswith lower-cost rawmaterials(i.e. fineoreand/ornon-metallurgicalcoalasthereductant)hadfavorablecombinedeconomics.In addition, the hot metal processes (in part due to the sensible heatimpacts in the EAF and due to their inherently lower costs) also hadfavorablecombinedeconomics.As a group, the Hot Metal processes had lower Total CumulativeElectricalPowerConsumption, lowerProcessEmissionsand lowerTotalEmissions(includingElectricalPowergeneration). Thesewerereflectedalso in theRankingSumAnalysis. Theexceptionwas theShaftFurnaceDRIprocess(Midrex)thatwasinthelowergroupfortheenvironmental-related variables.



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As anancillaryconclusionof this study, there is significantpotential toextend the viable economic life of the existing Blast Furnace Processinfrastructure (and perhaps future Mini Blast Furnace) by furtherdevelopingandexploitingtheevolvingcontinuousNon-RecoveryCokingprocesses. LockwoodGreeneisawareofseveralsuchprocessesthatarebeingdeveloped. Somehavehadsomepilotplant-scaleproductionandapplication testing, others are in the planning stages for pilotdemonstration.Whattheseprocesseshaveincommonare: Alldonothavetheenvironmentalburdenofproducinganddisposingofthenoxiouschemicalby-productsofthecokingprocess.

Allareenergyefficient (mostlyautogenous) andproducewasteheatthatcouldbeutilizeddirectlyortoco-generateelectricalpower.

Someutilizelow-costalternateandresidualcarbonsourcesaswellaslow-rank coals to produce a formed-coke product. The increasingcostsandshortageofhigh-gradecokingcoalismitigatedbytheuseoftheplentiful,low-costalternatives.

Mostofall,duetothecompletecombustionofthecokingby-productsand to integral pollution and emission controls, these non-recoverycoking processes as a group are much more environmentallyacceptablethanconventionalcokingprocesses.

In this Alternative Ironmaking Process Study, the differences in totalemissionsbetweenaconventional,co-productcokeBlastFurnaceandoneutilizing the continuous non-recovery coking process (coke substitutiononly) for these two, otherwise identical, cases indicated that therewasapproximately a 7% lower total emissions from the NonRecoveryCoke/Blast

Furnace

process

relative

to

the

Conventional

Co-Product

Coke/BlasFurnace.With the inclusion of co-generation that is an integral part of theContinuousNon-RecoveryCokeprocess, therewas a 22% reduction inemissionsduetototalcumulativeelectricalpowerrelatedemissions. Thiskindofenvironmentaldifferencemayprovideincentivesorconstraintstoutilizethelower-emittingtechnologies.



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The evolution of a lower-cost, energy-efficient and environmentally-friendlycokeproducingprocess that canutilize common carbon recycleandwastematerials aswell as abundant low-rank coal as the primarycarbonsourceswillhaveasignificantimpactonproductionofIronUnits.This alternative may extend the life of the existing Blast Furnaceinfrastructureand itmaypresent significantoptions for the adoptionofthemore-flexibleandlowercapitalcost(perironunitcapacity)MiniBlastFurnaceordevelopingprocessessuchasTecnored.



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Section2: StudyScopeandApproach2-1: StudyScope2-1.1: Introduction:Iron in the United States is largely produced from iron ore mined in theUnitedStatesorimportedfromCanadaorSouthAmerica. The ironoreistypicallysmeltedinBlastFurnacesthatuseprimarilyironore,metallurgicalcoke,limestoneandlimeastherawmaterials. Somealternatefuelsources,smallpercentagessuppliedbydirectcoal ornatural gas injection, arealsoutilized in place of the coke. Under current operating scenarios, the ironproducedfromtheseBlastFurnacesisrelativelyinexpensiveascomparedtocurrentalternativeironsources,e.g.directironreduction,importedpigiron,etc.TheprimaryproblemtheBlastFurnaceIronmakingapproachisthatmanyoftheseBlastfurnacesarerelativelysmall,ascomparedtothenewer,largerBlast Furnaces; thus are relatively costly and inefficient to operate. Anadditional problem is also thatsupplies of high-grade metallurgical gradecokearebecomingincreasinglyinshortsupplyandcostsarealsoincreasing.Inpartthisisduetotheshortsupplyandcostsofhigh-grademetallurgicalcoals, but also this is due to the increasing necessity for environmentalcontrolsforcokeproduction.Proposedandmandatedenvironmentalregulationsforcokeproductionwillsignificantly increase the shortfall of domestic cokeproduction during theinterimextensionperiodfrom1998-2003duringwhichnewcokeproductiontechnologiesandenvironmentalcontrolstrategiesaretobedeveloped.Afteryear

2003

new

regulations

for

coke

product

environmental

requirement

will

likelybepromulgated. Itislikelythatthisalsowilleitherincreasethecostofhigh-qualitycokeproductionorwill reduce the available domesticU.S.supply. Therefore,ironproductionintheUnitedStatesutilizingthecurrent,predominantBlastFurnaceprocesswillbemorecostlyandwouldlikelybecurtailedduetoacokeshortage.Utilization of higher percentages of imported coke in the existing BlastFurnace infrastructure will not solve the problems of short supply

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completelysincethetypicallyinferiorqualityof thesesourcesresultinlessBlast Furnaceproductivityand higher operating and maintenance costs.Thisimportedcokewilllikelyalsoincreaseincostandbecomeunavailableasthemarketdemandsincrease.Theremayberestrictionsortariffsontheuseofsuchimportedcokeifitisproduced under conditions such that significant environmental emissionsresult. Asisthecurrentcase,almostalloftheoffshoresourcesofimportedcoke(andthedomesticsourceswithfewexceptions)donotmeetcurrentorproposedU.S.environmentalstandardsforemissions. Asaconsequence,thismaynotbeasignificantviablesourceofsupplyafteryear2003.Therefore, there is a significant need to develop or extend the economicviability of Alternate Ironmaking Processes to at least partially replacecurrentanddecliningblastfurnace iron sources and toprovide incentivesfornewcapacityexpansion.2-1.2: Scope/Objective:A study was initiated to compare a number of Alternative IronmakingProcesses

by

Lockwood

Greene

Engineers

in

January,

2000

based

on

the

following Scope-of-Work. This work was done in conjunction withLockwoodGreeneTechnologieswhocontractedforthestudytoLockheedMartin Energy Research Corporation, the operating agency for the U. S.DepartmentofEnergyattheOakRidgeLaboratoriesfacility.Theobjectiveof thestudywas toevaluateanumberof alternativeprovenandpromisingironmakingprocessesthatwillfeedironunitstocurrentandfuture steelmaking processes. An initial review of available technologieswasmadewithaviewtowardgroupingforevaluationsimilarorderivativeprocesses. These groupings plus initial energy and mass balanceconsiderations allowed a preliminary screening, selection and finalgroupingsofthepromisingprocessalternatives.Reasonably accurateandrelativelyprecisemethodologieswere utilized todevelopquantitativemeasurementsofprocesscapitaland operatingcosts,energyconsumptionandenvironmentalemissions. Astandardscenariooftherequirementstoproduce1.0MMannualmetrictons(tonnes)ofrefinedliquid steel (by an Electric Arc Furnace and Ladle Refining Furnace,



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EAF/LRFscenario)wasutilizedtonormalizethebasisofcomparisonforallironmakingtechnologies.Thetrue objectiveof the studywastodefine thosealternative ironmakingprocesses that were lowest in costs while remaining environmentallyfriendly.

2-2: MethodologyandApproachEachprocessconsideredweredefinedandspecified,wherepossible, tothesame levelof confidence. In-houseLockwood GreeneEngineersdetailedprocess flow diagrams; spreadsheet mass balance models and processsimulationmodelswereutilizedasthebasisforthecomparisons. Foreachprocess,thebeginningpointofevaluationwastheprimaryironunitsourceand the finalpointofevaluationwas the refined liquid steel product. Inaddition,specificProcess Vendor inputs todefine thespecificsof theheatandmassbalancesandthecapitalandoperatingcostswerealsoutilized.Theprimaryreasonforthisapproachwastohavearelativecomparisonofthe cumulative energy consumptions (as electric power, fuel or otherconsumables)and toprovideabasisforthecumulativeemissionofcarbonwaste gases. For purposes of comparison, all carbon gases leaving theprocessweretakentobeasCO2.Theoverallmassandcomponentbalancesforeachofthesequenceandtrainof various preparation processes and unit operations preceding theironmaking and steelmaking processesdefines thespecificsizingand costfactorrequirementsfortheprecedingprocesses. Inaddition,thequantitiesof raw materials, fuelsand other commodities were defined for operatingcost development. The relationships for the primary raw materialsthemselvesarealsobuiltupfromtheirvariouscomponentsalso.Each component is defined and represented by a rigorous workingspreadsheet heat and materialbalance model. The combination of thevariouscomponentsresultsinasimilarbuilt-upspreadsheetmodelfor theprimary raw materials. Extending that further, these raw materialsproduction models are combined and strung together to form the unitprocessmodels.



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Forexample,thestepstoproduceanironorepelletareillustratedinFigure2-2.1below:

IRONOREMINING

DIESELFUEL

EXHAUSTGASES

IRONORECONCENTRATOR

WASTEROCK

IRONORE

ELECTRICPOWER

TAILINGS

ORECONCENTRATE CONCENTRATE

TRANSPORT(PIPELINE)

ELECTRICPOWER

ORECONCENTRATE ORE

PELLETIZINGELECTRIC

POWERFUEL

FLUEGASES

OTHER

INDURATEDIRONOREPELLETS

DIRECTREDUCTION

PROCESSFUEL

ELECTRICPOWER

FLUEGASES

DRIELECTRICARCFURNACE

STEELMAKING

FUELELECTRIC

POWER

INDURATEDIRONOREPELLETS

LIME/MgO(FLUX)

ELECTRODES

CHARGEC

STEELSCRAP

FLUEGASES

SLAG

SCRAP

DUST

LIQUIDSTEEL

FIGURE2-2.1BASEPROCESS- DRI/EAF

OXYGEN

Precedingtheproductionofironorepelletsaretheunitprocessesof: IronOreMining IronOreConcentrating TransportofConcentrate(e.g.slurrypipeline) ThenPelletizingSimilarly, the iron ore pellets are the primary raw material for the DirectReduction Process to product Direct Reduced Iron which, in turn, is theprimaryrawmaterial for the Electric Arc Steelmaking Process to producerefinedliquidsteel. ThedetailedcomponentBlockFlowDiagrams(BFDs)for the major raw materials for the Ironmaking Processes (e.g. electricalpower,tonnageoxygen,burntlime,non-recoveryandco-productcoke,etc.)arepresented in theAppendixA-3. Alsopresented inAppendix A-3 areBFDsforthemajorIronmakingProcessesshowingthesimilarmethodology



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for the built-up spreadsheet balance models utilized as the basis fordefinitionandcomparisoninthisstudy.2-2.1: IntroductiontotheMetSimProcessSimulatorThebasisforanalysisofallchemicalandmetallurgicalprocessesisthemassand energy balance. Plant design, capital costs, operating costs, andtechnical evaluationsare alldependent on such calculations. MetSim is ageneral-purposeprocesssimulationsystemdesigned toassist theengineerinperformingmassandenergybalancesofcomplexprocesses. MetSimusesanassortmentofcomputationalmethodstoeffectanoptimumcombinationofcomplexity,usertime,andcomputerresourceusage.MetSimcanperformmassandenergybalancecalculationsfor: Processfeasibilitystudies Alternativeflowsheetevaluations Pilotplantdataevaluation Fullscaleplantdesigncalculations

Operatingplant

improvement

studies

Actualplantoperationsandcontrol.MetSim performs mass and energy balances for chemical/metallurgicalprocessesusingthesequentialmodularapproach.Amajoradvantageofthisapproachisthatintermediateresultsmaybeobtainedfromanystageoftheprocessinanintelligibleform. Inconformancewiththesequentialmodularapproach, MetSim comprises modules containing subsets of equationsdescribingthedesignspecificationsandperformancecharacteristicsforeachprocess step. The system solves the equation subset for each module,allowingforanindividualanalysisofeachunitoperationintheflowsheet.Givendataondesignvariablesandinputstreamcomposition,eachmodulecalculatesalloftheoutputstreamvariablesthatcan thenbeused as inputstream values for the next process step. The modules access data on allindependent stream variables from the data arrays contained within theAPL (the computer language used for writing MetSim code) globalworkspace. Additional inputdatarequired tosolve theequations in eachmodulearerequestedby theprogram and arestored asglobal variables.



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Theuser may supply actual data obtained from operating or pilot plants,fromsimilarprocesses,orfromestimatessuppliedbytheengineer.Unlikemostotherprocesssimulators, MetSimeliminatestheneedforuserinvolvement in recycle stream tearing. MetSim employs a techniquewherebytheuserisrequiredonlytoprovideinitialestimatesoftherecyclestreamcontentofcriticalprocessstreams.Forprocessadjustmentandcontrol,MetSimusesfeedforwardandfeedbackcontrollers. BecauseofsimilaritybetweenthedynamicbehaviorofMetSimcontrol and that of process control in operating plants, unstable controlstrategiescan oftenbe located during the modeling stage, avoiding costlyfieldmodificationandretrofit.ThesuccessfulapplicationoftheMetSimsystemofprogramsinvolvesmorethansimplyenteringfixeddataonstandardizedinputsheets. Duetowidevariation in chemical and mineral processing techniques, available data,processcriteria,andoutputdatarequirements,thedevelopmentofprocessmodels is as much an art as it is a science. It involves familiarity withmathematical modeling, numerical analysis and process control. The usermust

be

familiar

with

process

engineering

mass

and

energy

balance

calculations.Thusitsupplements,notreplaces,soundengineeringpracticesandjudgment.



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2-2.2: SimulationModelsofIronmakingProcessesAprimarycomponentindevelopinganddefiningthecombinedcomponentSpreadsheet Heat and Mass balance models of the various IronmakingProcessesaretheMetSimSimulationModelsoftheIronmakingProcesses.Asdiscussedearlier,thebalancesforthevariousIronmakingProcessesarenormalizedusingthebasisofproductionasbeing1.0MMtonnesofRefinedLiquid Steel (RLS) per year as the common denominator. In all casesconsidered, the RLS production route utilized the various forms of ironproduced(i.e.liquidhotmetal,coldpigiron,directreducediron,etc.)bythevarious Ironmaking Process as the primary iron source to an appropriateEAF/LRFoperation.The commercially-available MetSim process simulation software system(Proware,Phoenix,AZ)asdescribedinSection2.2.1wasutilizedtodevelopthe rigorous simulation models of most of the various IronmakingProcesses. MetSimprovidesthesystembywhichthefundamentalchemicalreactionsandequilibriaintheGas,LiquidandSolidphasesofIronmakingcanbesimulatedunderasimultaneousequilibriumoperatingconditions.However, the model developer must define these fundamental chemicalreactions,

the

chemical

yields

or

extent

of

reaction,

the

components

for

the

variousphasesand organize themodel tosimulatetheentireflowsheetoftheIronmakingProcess.Such a process simulation model (as opposed to a simple spreadsheet

balance model) will actually predict thebehavior and performance of theentire process. The entire flowsheet itself including: the process, thereducing gas production and recirculating streams, the cooling waterrequirements,andtheoff-gasesoremissionsaremodeled.Controlsandprocesscontrolloopsareprovided(asintheactualoperatingprocess) to allow the modeler to specify and constrain the processperformance and product requirements. As changes are made in theassumptions for raw materials, process inputs or for operating conditionsaremadebythemodeler,thepredictionofthevariationsoftheoutcomesofthesimulatedprocesscanprovidesensitivitiesofproduction,yield,productquality,etc.



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LockwoodGreenehasdevelopedsuchmodelsforthefollowingIronmakingProcesses: BaseCaseMidrexShaftFurnace HylsaHYLIVM(ReformerlesswithHotDRIChargetoEAF) TecnoredShaftMelter HiSmeltOxygenReactor RedsmeltRotaryHearthFurnace CircoredFluid-BedReductionProcess(NaturalGasReductant) CircoferFluid-BedReductionProcess(CoalReductant) GenericIronCarbideProcess(Single-Stage,Two-StageorMulti-Stage)ThemodeloutputsforatypicalIronmakingsensitivitycasesforeachmodelarepresentedinAppendixE.Whatisimportanthere isthatthesebasicsimulationmodelswereused inthisStudytoevaluateandverifyVendor-Suppliedheatandmaterialbalancedata, production data and operating assumptions. Once verified, theMetSimmodelsfortheIronmakingProcesseswereusedtotuneoradjusttheSpreadsheetModelsfor theoverallprocess(throughEAF/LRFLRS) toprovide realistic raw material, component and energy (fuel plus electricalpower)balancesystems.



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ThismethodologyisillustratedinFigure2-2.2below:

IRONMAKING PROCESS

SPREADSHEETMODEL

COMPONENT1PRODUCTION

SPREADSHEETMODEL


SPREADSHEETMODEL


SPREADSHEETMODEL

EAF

STEELMAKINGPROCESS

SPREADSHEETMODEL

METSIMIRONMAKING

PROCESSHEAT&MAT.

BALANCEMODEL

METSIMSTEELMAKINGPROCESS

HEAT&MAT.BALANCEMODEL

IRONMAKINGPROCESS

SPREADSHEETSTEELMAKING

PROCESSSPREADSHEET

RIGOROUSHEAT&MATERIALBALANCE

MODELS(METSIM)

SUMINDIVIDUALCONTRIBUTIONSTO

ELECTRICALPOWERANDGREENHOUSEGAS

EMISSIONS

FIGURE2-2.2METHODOLOGYFOREACHIRONMAKINGPROCESS

INDIVIDUALCOMPONENTBALANCES

(I.E.RAWMATERIALS,ELECTRICPOWER,FUELS,ETC.)

2-2.3 SpreadsheetMassBalancesofProcessComponentsAsillustratedabove,eachoftherawmaterialcomponentsutilizedasfeedsto the Ironmaking or Steelmaking processes were also defined byappropriatespreadsheetheatand materialbalances. Thesewerepreparedfor

the

major

components

and

also

for

the

intermediate

Unit

Processes

so

that the cumulative fuel and electrical energy requirements could beaccountedfor. Inaddition, thesecomponentbalance modelsprovide the

basisfordefiningthecumulativeprocesscarbon-gasemissions(alltakentobeasCO2)foreachprocessandprocesssteptoserveasrelativeindicatorsforcomparisonofthediverseIronmakingProcesses.



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ThespreadsheetmodelbalanceutilizedforthecomponentsareprovidedinAppendixBfor: ElectricalPowerGenerationCoal,NaturalGas&FuelOil(Basisfor

CumulativeGreenhouseGasEmissionperkWhrAsCO2) LumpIronOre PelletizingBinderBentonite Coal

BurntLime/Dolomite OxygenGas CarbonElectrode Co-Product(ConventionalBy-Product)Coke Non-RecoveryCokeProcessWithCo-Generation(BasedonAntaeus

EnergyProcess) OtherRawMaterialAssumptions2-2.4

Spreadsheet

Mass

Balances

of

Ironmaking

Processes

As illustrated above in Figure 2-2.2, the component mass balancespreadsheets are integrated with the Unit Process spreadsheets of theupstream operations preceding Ironmaking and Steelmaking. These, inturn,integratewiththedetailedprocessspreadsheetmassbalancesfor theindividualIronmaking Processesand thesubsequentEAF/LRF operationstoproduceLRS.The following examples of the totally-integrated process spreadsheetsutilized inthestudyare illustrating the level of detail utilized to establishthe processbalances, define fuel and energy consumptions and estimateprocess emissions. The complete spreadsheet listings are provided inAppendixD: 100%DRIChargedtoEAF- 1.0%Carbon 100%DRIChargedtoEAF2.5%Carbon 30%DRIChargedtoEAF- 1.0%Carbon 100%ScrapChargedtoEAF(ForReferenceOnly)



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Spreadsheet summarybalances were prepared for the major IronmakingProcessscenarios(i.e.variousprocess typesandEAFproductionscenariosfor LRS) selected from the initial screening analysis. These provide thecomponent quantities and logic from which process Operating Costs,emissionestimatesand energy consumptionsaredeveloped asabasis forprocesscomparison.Process descriptions of the Ironmaking Processes considered in the studyare provided in Appendix A-1 and simplified Ironmaking Process FlowDiagrams(PFDs)areprovidedinAppendixA-2.The Summary Spreadsheets for the process scenarios are provided inAppendixC:SHAFTFURNACEDRIVARIATIONINCARBONANDSCRAPCHARGE BaseCase: 100%ShaftFurnaceDRI(i.e.Midrex)ChargetoEAF,1.0

wt.%DRI(RecycleSteelScrapOnly) 100%ShaftFurnaceDRI(i.e.Midrex)ChargetoEAF,2.5wt.%Carbon

(RecycleSteelScrapOnly) 100%SteelScrapChargetoEAF(ForReferenceOnly) 30%ShaftFurnaceDRI/70%ScrapChargetoEAF(aCommonIndustry

Practice),1.0wt.%DRICarbon 30%ShaftFurnaceDRI/70%ScrapChargetoEAF(aCommonIndustry

Practice),2.5wt.%DRICarbon HylsaShaftFurnaceWithoutReformer(HYL IVM),HotDRIChargeto

EAFHOTMETALVARIATIONS 30%BlastFurnaceHotMetal/70%ScrapChargetoEAF,Co-Product

Coke MiniBlastFurnaceComparison@30%H.M./70%ScrapChargetoEAF,

Co-ProductCoke



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30%BlastFurnaceHotMetal/70%ScrapChargetoEAF,Non-RecoveryCoke

30%ColdPigIron/70%ScrapChargetoEAF,4.5%Carbon 30%TecnoredHotMetal/70%ScrapChargetoEAF,4.5%Carbon

H.M.WithIntegralCo-GenerationofElectricalPower 30%TecnoredHotMetal/70%ScrapChargetoEAF,4.5%Carbon

H.M.WithoutCo-GenerationofElectricalPower Corex(VAI)/Midrexwith60%HotMetaland40%DRIChargetoEAF HiSmelt(ISCON)with34.5%HotMetalChargetoEAFROTARYHEARTHFURNACES Redsmelt(Mannesmann)HotMetalWithOnlyRecycleScrapChargeto

EAF MauMeeR&EBriquetteDRI/EAFWithOnlyRecycleScrapChargeto

EAF ITMK3(MidrexRHF)toEAFWithOnlyRecycleScrapChargetoEAFFLUID-BEDDRI/HBI Circored(Lurgi)/HBI/EAFWithOnlyRecycleScrapChargeto Circofer(Lurgi)/HBI/SAF/EAFWithOnlyRecycleScrapChargeto

EAF Finmet(VAI)/HBI/EAFWithOnlyRecycleScrapChargetoEAF GenericIronCarbide(ICH)/EAFWithOnlyRecycleScraptoEAF

(RepresentsNucor/ICH,Qualitech/Kawasaki,ProcedyneProcesses) 40%IronCarbideCharge/60%ScraptoEAF(BelievedtobeMaximum

PracticalorFeasibleChargeRatio)OTHERPROCESSES SL/RN(Stelco-Lurgi)RotaryKilnWithOnlyRecycleScrapChargeto

EAF



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2-3: BaseProcessLocation2-3.1 BaseLocationAssumptionsIn an initial screening of a number of Ironmaking process,both provencommercialanddevelopingprocesses,itwasrecognizedthatthelocationofthe processcouldhaveasignificantimpacton thetechnicaland economicviability of that process. A number of factors related to location wereconsideredtobepotentiallycriticalinevaluatingandcomparingprocesses.Some of these are related to raw material supply, others to proximity tomarketsfortheproductsandsomerelatetolocaleconomicconsiderationsofrawmaterialsorlaborcosts.Thesefactorsrelatingtolocationinclude: Proximitytooresource Proximitytopelletsource(forthoseprocessesutilizingpellets) Localfuel(i.e.reductant)sources Costs,skillsandproductivityoflocallaborforce Localmarketfor product(assumed tobe steelslabs from downstream

Steelmakingoperations) Availability of low-coststeel scrap sourcesofadequate purity for EAF

Steelmaking Localenvironmentalregulations,constraints,etc.Itwasclear in the initial evaluation and screening of potential alternativeironmakingprocesses(tothatofBlastFurnaceIronhotmetalorpigiron),thatlocalproximity to low-costreductantsources(i.e.eithernaturalgasorappropriatecoalresources)wouldbeasignificantswingvariableinrankingofthepotentialalternateprocesses. Thislocalproximitytofuelwouldnotonlyimpactonthechoiceofreductanttype,itwouldinfluencethechoiceofprocesstype,i.e.thatwhichwouldutilizenaturalgasor thatwhichwouldutilize coal as the primary reductant. These considerations arepredominatelyeconomic,butcouldalsoberelatedtoenvironmentalimpactoradesiredsteelmakingprocessironunitfeed.



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2-3.2 LocationSensitivities ProximitytooresourceThe most significant component of Operating Costs for the Ironmakingprocessesisthecostofironunitssuppliedtotheprocess. Anotherfactoristheformoftheironunitrawmaterialdelivered(i.e.ashigh-gradelumpore,pelletsfromironoreconcentrateorironorefines). Asignificantadditionalfactoristheavailabilityofsupplyofthedesiredironunitrawmaterial. AllofthesefactorsarerelatedtothelocationoftheIronmakingprocessrelativetothesourceoftheironunitrawmaterial.SincesomeIronmakingprocessperformancefactorsrelate to thequalityofthe iron unit feed, close proximity to the source may provide a morefavorableaccesstothemostdesirablefeedmaterial. Thiscanimpactoftherelativeperformanceofoneprocessoveranother. Forexample, theremay

be alternate methods of delivery (e.g. slurry pipeline) or availability ofquantitiesatsignificantly-lowercostper ironunitfor orefines. Processesthat can directly utilize them, perhaps without further beneficiation orpalletizing,couldhavealocaladvantage.Similarly,rawmaterialcostfactors(i.e.materialhandlinganddeliverycosts,availabilityof low-costfines,etc.) may influencesignificantlythechoiceofIronmaking process. Availability of suitable port, rail or other deliveryfactorsforrawmaterialsandacceptableaccesstothe rawmaterialsourcesmaypartiallymitigatealocation-relatedfactorfortheironunitfeeds.Inthisstudy,anupperMidwestU.S.A. locationwaschosen(i.e.NorthernOhio or Indiana) to provide a Target Location that would have all of therequiredfactorsforrawmaterialdeliverysoastonotsignificantlybiastherelative Ironmaking process evaluation and comparisons. Delivered rawmaterialcostsandavailabilityareacceptableforthatlocationandwouldnotnecessary favor one process over another. However, in this fashiondeliveredcostsofrawmaterials(includingsupplyandtransportation)werethusnormalized,butnotnecessarilyoptimized,forallprocesses.



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ProximitytopelletsourceForthoseprocessesutilizinginduratedironconcentratepellets,therecould

be significant impacts of location relative to the source of concentrates ordirectreductiongrade(DR)pellets. Anironmakingprojectthatincludesitsown source of ore, concentrates and subsequent pellet production, mayfavorselectionofanironmakingprocessthatbenefitsmostdirectlybythatconstancy of feed quantity and quality. An example of this is the ShaftFurnaceDRIprocesses,MidrexorHylsa.Duringhigh-ironproductiontimes,therecouldevenbeshortagesofsupplyofthemostdesirablepelletfeedsforsomeIronmakingprocesses. Closenesstothesourceofpelletsmaypresentanadvantageinavailabilityordeliveredcost. Asdescribed above, thechoiceofanupperMidwestU.S.A. locationwasdesignedtoneitherpresentanadvantageortobeadisadvantagetotheselectionorcomparisonofIronmakingprocesses. LocalfuelsourcesSecond in importancerelated toLocation, is thatof the fuel (orreductant)sourceand/ortype. Therewilldefinitelybeadvantages,similartothosefor iron unit supply, to any of the Ironmaking processes is they canbelocatedclosetoareadily-available,low-costfuelsupply. Asnotedabove,the fuel supply (rate and quality) and delivered cost willbe a primaryconsiderationintheselectionoftheIronmakingprocesstype.If low-cost coals of the proper type are available in a particular locationversusahigher-costsupplyofnaturalgas,thismayinfluencetheselectionof a coal-based reductant ironmaking process. If metallurgical coal (forconventional cokeproduction) is in short supply or is at a premium cost,selection

of

aprocess

(e.g.

rotary

hearth,

Tecnored

or

non-recovery

coking)

thatcanutilizelower-cost,readily-available,low-rankcoalsmaybetheonlyprocess option. A similar situation where synthesis gas in quantity (i.e.SasolGasatSaldanha,SA.)isavailablemaydictatetheironmakingprocessselectionduetofavorablefuelgaspropertiesforthatprocess.In some locations, low-cost natural gas or suitable coal may not evenbeavailablelocally. Thus,therelativecostsofimportingthequantitiesoffuelnecessarycouldinfluencesignificantly thechoiceofIronmakingprocessor



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the overall project economics. The choice of an upper Midwest projectlocationdoesnotnecessarilyfavoronefuelsourceoveranother. Costs,skillsandproductivityoflocallaborforceLaborcostsasafractionoftheOperatingCostsforironorsteelproductarearelatively-lowpercentage(10%orlessofthetotals). Differencesinlaborratesfromonesite location to theotherwouldnot significantly impactonthe overall production costs. An important factor maybe local laborproductivity. In some countries, or in some regions of North America,effectiveproductivityof labornotcompensatedfor inthe laborrates,mayhave an impact on the costs of production for some of the Ironmakingprocesses. Therearesignificantdifferencesin themanpowerrequirementsforsomeoftheironmakingscenarios(whennormalizedtoNorthAmericanstandards) that could influence the choice of process or overall projecteconomics.Moreimportantly,however,someIronmakingprocesses,inparticularthosehigher-technology processes in development or in their first-of-a-kindprototypephase,couldrequireamorehighly-skilled laborforcetooperateormaintain. Thismaynotbereadilyavailable,wouldcommandanextra-ordinarily-high premium on labor rates or would require importation ofskilled labor for some processes in some locations. This could influencesignificantlythechoiceofprocessrelatedtoaspecificlocation.The upper Midwest location should neither present an advantage nor adisadvantagetoanyspecificIronmakingprocess. Itwouldhaveanoverallfavorable labor market due to the high skill and experience levels of theavailable work force and a general familiarity with heavy industrialprocessessuchasironmakingandsteelmaking. LocalmarketforproductIngeneral,theupperMidwestU.S.A.locationwouldbeafavorableoneforasteelslabproductproducedfromanyoftheIronmakingprocesses. TheabilityofsomeIronmakingprocesses(particularlythoseproducingDRI)toproduceafavorablylowimpurityscrapsubstituteironfeed,couldfavortheproduction of low-impurity steel for specific industry (e.g. deep drawingqualityautobodygrades,etc.). However, themarketforall typesofsteel



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from this general location would not favor one type of process over theother.Shipmentortransportationofthefinishedsteelslabproductwouldalsobegenerally favorable with options including water shipment, rail or truckshipment of the steel product. There is also the possibility of closeintegration with an existing customer for a steel slab product that wouldeliminatethenecessityofproductshipping. Availabilityoflow-coststeelscrapA significant finding of this Alternative Ironmaking Study is that theselectionofanIronmakingprocess(forultimateEAF/LRF steelmaking) isdirectlyinfluencedbytheavailability,costandpurityofsteelscrap. Thisisnotonlyasignificantfactor intheselection of the appropriate Ironmakingprocess,but in thenetfinalcostofthefinalLRSproduct. Itmaybe thatthose ironmaking processes that most efficiently combine with the EAFsteelmakingtominimizethequantityorquality(i.e.costsoravailability)ofsteelscrapwouldbetheonlyeconomically-viableIronmakingprocessesofchoiceinahighcoststeelscrapmarket.DiscussedinSection2-4andinSection4,thesteelscrappricesensitivityisaprimary factor in Ironmaking process selection. With the fluctuation insteelscrappriceswiththepasttwoyearsoverarangeofapproximately+/-50% from the average (see Figure 2-3.1below), ironmaking processes (incombinationwithEAF/LRF)thatareviableatmedianorlowerscrappricesarenotviableattheaboveaveragescrapprice.



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Steelmakingthatrequiresahigher scrapchargewouldhaveanetresultofhighersteelmakingcosts.

FIGURE2-3.1: STEELSCRAPPRICECOMPOSITE($/mtWEEKLYFROMJANUARY1998)

$180.00$160.00$140.00$120.00$100.00$80.00$60.00$40.00$20.00$0.00

0 20 40 60 80 100 120 140 160WEEKLYFROMJAN.1998

SCRAPCOMP. MEDIANPRICE

ThisalsoworksagainstthoseIronmakingprocessesthataredesigned tobescrapsubstitutes, i.e.DRIproducerssuchastheshaftfurnaces. ItisatrueperspectivethatShaftFurnaceDRIfacilitiesthatwere installedjustoneortwo years ago under a favorable economic climate (e.g. moderate scrapprices)became uneconomically viable and with no competitive market atlowscrapprices. Localenvironmentalregulations,constraints,etc.A key part of the initial evaluation and process screening phases of thisAlternative Ironmaking Study was the overall impact on greenhouse gasemissions for each process (as represented in the Study by total thecumulative carbon gas emissions as CO2). Not only is this factor animportant one in comparing the various processes, it is one that couldimpactontheabilitytoinstallaparticularprocessataspecificlocation.Thereareseveralforcesareworkingagainsteachother. Oneisthatthetotallocal emissions for a given process may exceed the Local environment



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regulatorystandardsorlimits;thusprohibitingselectionofthatprocessforthatspecificlocationorrequiringextra-ordinarymitigationandcontrol. Asecondfactoristhatofthecumulativetotalemissionsfor theentiretrainoftheprocess(i.e.oremining,concentration,pelletizing,etc.)maybehighandthus would have a broad impact on the total environment. A lastenvironmental factor is that the total electrical power requirements for aprocess are high. This also would have a broad impact on the totalenvironment since there are significant emissions (on the average for aU.S.A. location, See Appendix A-3.1) associated with electrical powergeneration that cannotbe ignored when comparing processes to produceLRS.Itwillbe noted in the comparative analysisbelow (Section 4-7) that coal-

based reductant processes typically have significantly more emissions (asCO2) than natural gas reductant processes. A local environmentalrestrictionorconstraintmaydictate theuseofanIronmakingprocesswithlowerlocalemissionlevels.TwospecificironmakingscenarioswereevaluatedinthisStudywherethereis a significant difference of the impact of emissions from the cokingproduction

processes.

The

production

of

coke

for

use

in

ablast

furnace

is

a

significantcontributortotheoverallemissionsoftheblastfurnaceprocess.The first scenario is one that the conventional Blast Furnace processproduceshotmetalutilizingconventionalco-productcokeproduction. Thesecond is one where the blast furnace produces hot metal utilizing anevolving, continuous non-recovery coke production process. For thesecases, no differences in the blast furnace productivity or chargerequirementswereassumedasaresultoftheuseofonetypeofcokeortheother.(Note: Physical and chemical parameters for the briquetted form cokeproducedby thenon-recovery process may indicate that, infact, theblastfurnaceproductivitycouldbehigher.)The comparison of the total emissions for these two, otherwise identical,cases indicated that there was approximately a 7% lower total emissionsfrom the NonRecovery Coke/Blast Furnace process relative to theConventionalCo-ProductCoke/BlasFurnace. With the inclusionofcogeneration that is an integral part of the Continuous Non-Recovery Coke



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process, there was a 22% reduction in emissions due to total cumulativeelectrical power related emissions. Thiskind of environmental differencemay provide incentives or constraints to utilize the lower-emittingtechnologies.

2-4: ProcessCapital(CAPEX)andOperatingCostEstimates2-4.1: ProcessCapitalCosts(CAPEX)The Relative Capital Cost (CAPEX) estimates for each of the AlternativeIronmaking Processes were developed from appropriate Iron andSteelmaking Unit Operation internal LGE Cost, Feasibility or DetailedDesign Studies. In addition, some specific Process Vendor inputs wereutilizedtoprovideamostrecentestimatebasisorwheretheappropriatein-housedatawere notavailable. The installed cost estimates were factoredusinginternalLGEfactorsforthecostsforsimilarscopesforprocessareasor planttypefor each of theIronmakingProcesses. Where commoncostareasarepresentfordifferentIronmakingprocesses,e.g.pelletizingplant,thebasis costs were factored for each Ironmaking process according tocapacityrequirements.Thecostsusedwereupdatedtoayear2000basisandnormalizedusingtheprocessMassBalances(AppendixC)toauniform1.0millionmetrictonnesperyearRefinedLiquidSteel(RLS)productionbasis. Specificdifferencesinscoperequired for a particular Ironmaking process were accounted for inthe individual components considered in the overall process CAPEXestimates(summarizedindetailinVolumeII,AppendixF-5). TheCAPEXisreportedas$/annualmetrictonneofproduction.

Theanalysis

of

the

relative

CAPEX

estimates

for

the

various

Ironmaking

processscenarioswillbepresentedinSection4.2.



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The built-up CAPEX costs are presented in Appendix F-5 and aresummarizedintheTable2-4.1below:

Table2-4.1CAPITALCOSTESTIMATES- IRONMAKINGANDEAF/LRFPROCESSES

APPENDIX PROCESS CAPEXNO. ($/ANNUALmtL.S.)

SHAFTFURNACEDRIPROCESSES:C-1 100%ShaftFurnaceDRIchargetoEAF,1.0wt.%Carbon $365.36C-2 100%ShaftFurnaceDRIchargetoEAF,2.5wt.%Carbon $365.45C-3 100%SteelScrapchargetoEAF $173.68C-4 30%ShaftFurnaceDRI/70%ScraptoEAF,1.0wt.%DRICarbon $231.85C-5 30%ShaftFurnaceDRI/70%ScraptoEAF,2.5wt.%DRICarbon $232.70C-6 HYLSAShaftFurnacewithoutreformer,HotDRIchargetoEAF $362.60

HOTMETALVARIATIONSC-7 30%BlastFurnaceHotMetal/70%ScraptoEAF,Co-ProductCoke $243.64C-7a 30%BlastFurnaceHotMetal/70%ScraptoEAF,MiniBlastFce. $198.05C-8 30%BlastFurnaceHotMetal/70%ScraptoEAF,Non-Recov.Coke $243.63C-9 30%ColdPigIron/70%ScraptoEAF,4.5%CarbonPig $248.06C-10 30%TechnoredHotMetal/70%ScraptoEAF,withCo-Generation $196.48C-11 30%TechnoredHotMetal/70%ScraptoEAF,withoutCo-Gen. $187.71C-12 COREX/MIDREXwith60%HotMetal/40%DRIchargetoEAF $373.50C-13 HISMELTwith32.7%HotMetalchargetoEAF $259.63

ROTARYHEARTHFURNACESC-14 REDSMELTHotMetalwithonlyRecycleScraptoEAF $334.67C-15 MAUMEEBriquetteDRI/EAFwithonlyRecycleScraptoEAF $292.32C-16 ITMK3toEAFwithonlyrecyclescrapchargetoEAF $296.10

FLUID-BEDDRI/HBIC-17 CIRCORED/HBI/EAFwithonlyRecycleScrapchargetoEAF $232.37C-18 CIRCOFER/HBI/SAF/EAFwithonlyRecycleScrapchargetoEAF $239.63C-19 FINMET/HBI/EAFwithonlyRecycleScrapChargetoEAF $263.47C-20a

Generic

IRON

CARBIDE/EAF

with

only

Recycle

Scrap

to

EAF

$347.59

C-20b GenericIRONCARBIDE/EAFwith60%ScrapchargetoEAF $257.24

OTHERPROCESSESC-21 SL/RNRotaryKilnwithonlyRecycleScrapchargetoEAF $344.39



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2-4.2 ProcessOperatingCosts(OPEX)The approach followed in developing the operating costs for the variousIronmakingProcesseswastobuilduptheoperatingcosts(OPEX)fromtheindividualcomponentsofeachprocessscenario.Thebasesforthesecostsinclude: Consumable components as defined by the mass and fuel balances

(AppendixB). ElectricalpowerconsumptionsfromexperienceorProcessVendordata. Labor estimates were factored from man-hour/mt data supplied by

ProcessVendorsandfromLGEexperiencewithsimilarprocesses. Costsand/orfuelcostsfortransportofmaterials. Allowances for maintenance materials and suppliesbased on Vendor

factors. Asappropriate,allowancesforG&Awereadded.Eachprocesscomponentcostwasbuiltupusingtheabovefactorsforeachunitoperationinvolvedinproducinganddeliveringtheconsumabletotheironmakingprocess.In tables in Appendix F-1, the Consumable Component costs are definedandsummarizedfor: BentoniteBinder Coal(lumpdeliveredtouse)

BurntLime/Dolomite

LumpIronOre FineIronOre IronOreConcentrate IronOrePellets Co-ProductCokeProduction



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Non-RecoveryCoke/withCo-Generation SteelScrapCompositePriceBasis2-4.3 IronmakingProcessConsumptions&RelativeOperatingCostsTheIronmakingProcessConsumptionsandtheir RelativeOperating Costsarebuiltupfromthecostsofthevariousconsumablematerialsinasimilarmanner. Consumablecomponents as definedby the mass and fuelbalances for

theIronmakingProcesses(AppendicesC&D). ElectricalpowerconsumptionsfromexperienceorProcessVendordata. Labor estimates were factored from man-hour/mt data supplied by

Process Vendors and from LGEs in-house experience for similarprocesses.

Costsfortransportofmaterialsincludedinmaterialcosts. Allowances for maintenance materials and suppliesbased on Vendor

factors. Other consumable cost assumptions, e.g.composite steel scrap; overall

labor cost per man-hour, natural gas, electrical power, and otherdelivered materialsarebased onanupper Mid-WestU.S.A. location.These were derived from negotiated commodity costs achieved for arecent large-scale project in that region. (Note: Costs for electricalpower,fuel,etc.werefirst-quarter2000. Theywerenotchangedduetorecentescalations. Itisbelievedthatmostrelativecomparisonswillstill

bevalid.) Asappropriate,allowancesforG&Aand/orVendorfeeswereadded.Each Ironmaking Process Cost was derived from the summation of theindividualcostsofeachunitoperationinvolvedinproducingtheIronUnitsandsubsequentproductionofEAF/LRFRefinedSteelProduct.TheProcess Operating Costs, (OPEX), developed in theabove fashion are

believed to be relatively precise as a basis for comparing the variousprocesses onanequalized footing. By normalizingall processes throughthe production of the Refined Liquid Steel product, all typesof iron units



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producedby theIronmaking Processescanbecompared. Thus hot metalproducingprocessesarecomparableonanequalizedbasistodirectreducedironproducingprocesses. Therelativeaccuracyofeachof thecomponentsof the OPEXbased onclosure of the massbalancesshouldproduceafairoverallcostforeachprocessthatcanbecomparedaccuratelytoeachother.It is alsobelieved that the absolute accuracy of these OPEX costs is alsorelativelyprecise. Spotchecksoftheestimatedcostsandcomparisonswithrecent detailed feasibility studies using Vendor data of these and similarprocesses have verified the accuracy of the built up operating costcalculationprocedure.



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The Table 2-4.2 provides a summary of the primary Ironmaking ProcessOperatingCosts(aspresentedindetailinVolumeII,AppendixF-4):

Table2-4.2OPERATINGCOSTESTIMATES- IRONMAKINGANDEAF/LRFPROCESSES

APPENDIX PROCESS OPEXFORI.U. OPEXFORL.S.NO. ($/ANN.mtI.U.) ($/ANN.mtL.S.)

SHAFTFURNACEDRIPROCESSES:C-1 100%ShaftFurnaceDRIchargetoEAF,1.0wt.%Carbon $132.44 $205.39C-2

100%

Shaft

Furnace

DRI

charge

to

EAF,

2.5

wt.%

Carbon

$132.55

$206.42

C-3 100%SteelScrapchargetoEAF $0.00 $197.39C-4 30%ShaftFurnaceDRI/70%ScraptoEAF,1.0wt.%DRICarbon $137.51 $203.36C-5 30%ShaftFurnaceDRI/70%ScraptoEAF,2.5wt.%DRICarbon $136.14 $204.72C-6 HYLSAShaftFurnacewithoutreformer,HotDRIchargetoEAF $125.52 $196.15

HOTMETALVARIATIONSC-7 30%BlastFurnaceHotMetal/70%ScraptoEAF,Co-ProductCoke $142.86 $204.39C-7a 30%BlastFurnaceHotMetal/70%ScraptoEAF,MiniBlastFce. $142.86 $204.39C-8 30%BlastFurnaceHotMetal/70%ScraptoEAF,Non-Recov.Coke $110.77 $192.97C-9 30%ColdPigIron/70%ScraptoEAF,4.5%CarbonPig $145.12 $212.79C-10 30%TechnoredHotMetal/70%ScraptoEAF,withCo-Generation $125.95 $192.41C-11

30%

Technored

Hot

Metal/70%

Scrap

to

EAF,

without

Co-Gen.

$163.09

$205.72

C-12 COREX/MIDREXwith60%HotMetal/40%DRIchargetoEAF $208.88 $228.34C-13 HISMELTwith32.7%HotMetalchargetoEAF $137.85 $198.19

ROTARYHEARTHFURNACESC-14 REDSMELTHotMetalwithonlyRecycleScraptoEAF $101.83 $190.67C-15 MAUMEEBriquetteDRI/EAFwithonlyRecycleScraptoEAF $66.44 $177.03C-16 ITMK3toEAFwithonlyrecyclescrapchargetoEAF $67.60 $181.12

FLUID-BEDDRI/HBIC-17 CIRCORED/HBI/EAFwithonlyRecycleScrapchargetoEAF $78.79 $185.27C-18 CIRCOFER/HBI/SAF/EAFwithonlyRecycleScrapchargetoEAF $96.20 $188.55C-19 FINMET/HBI/EAFwithonlyRecycleScrapChargetoEAF $79.42 $185.12C-20a

Generic

IRON

CARBIDE/EAF

with

only

Recycle

Scrap

to

EAF

$66.19

$177.84

C-20b GenericIRONCARBIDE/EAFwith60%ScrapchargetoEAF $100.79 $192.65

OTHERPROCESSESC-21 SL/RNRotaryKilnwithonlyRecycleScrapchargetoEAF $74.08 $183.10

Basis: $120/mtCompositeSteelScrapCost

The Ironmaking Process Operating Cost details are summarized inAppendixF-4forthefollowingprocessscenarios:



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SHAFTFURNACEDRIPROCESSES Base Process Shaft Furnace (i.e.Midrex), 100% DRI charge to EAF, 1.0

wt.%DRICarbon(AppendixC-1) Base Process Shaft Furnace (i.e.Midrex), 100% DRI charge to EAF, 2.5

wt.%DRICarbon(forreference,AppendixC-2) Electric Arc Furnace Steelmaking, 100% Steel Scrap Charge (for

reference,AppendixC-3)

Base Process Shaft Furnace (i.e. Midrex), 30% DRI/70% Steel Scrapcharge to EAF (a common industry practice), 1.0 wt.% DRI Carbon(AppendixC-4)

Base Process Shaft Furnace (i.e. Midrex), 30 % DRI/70% Steel ScrapchargetoEAF(forreference,AppendixC-5)

HYLSA IVMShaftFurnace without reformer, 100% hot DRI charge toEAF,(AppendixC-6)

HOTMETALVARIATIONS Blast Furnace Hot Metal (30% H.M./70% Steel Scrap charge to EAF),ConventionalCo-ProductCoke(AppendixC-7) Mini Blast Furnace Comparison (30% H.M./70% Steel Scrap charge to

EAF),Co-ProductCoke Blast Furnace Hot Metal (30% H.M./70% Steel Scrap charge to EAF),

Non-Recovery Coking process with Co-Generation (for comparison,AppendixC-8)

Cold Pig Iron (30% P.I./70% Steel Scrap charge toEAF), ConventionalCo-ProductCoke(AppendixC-9)

Tecnored Hot Metal (30% H.M./70% Steel Scrap charge to EAF) withintegralCo-GenerationofElectricalPower(AppendixC-10)

TecnoredHotMetal(30%H.M./70%SteelScrapchargetoEAF)withoutCo-GenerationofElectricalPower(AppendixC-11)

Corex(VAI)/MidrexShaftFurnacecombinationprocess,60%H.M./40%DRIchargetoEAF(AppendixC-12)



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HiSmelt Enriched Oxygen Reactor Process, 32.7% H.M. feed to EAF(AppendixC-13)

ROTARYHEARTHDRIFURNACES REDSMELT (Mannessmann) process to produce RHF DRI, Hot Metal

utilizingaSAF,recyclescraponlychargetoEAF(AppendixC-14) MauMeeResearch&EngineeringBriquetteDRIcharge(100%withonly

recyclescrapchargetoEAF)(AppendixC-15) ITMK3 (Midrex RHF) process producing reduced shot iron pellets

charge to Melter/EAF (100% with only recycle scrap charge to EAF)(Appendix C-16) (Note: Other Rotary Hearth Processes, e.g. Inmetco,IronDynamics,FastMet/FastMelt,etc.aresogenericallysimilartothoseabove,thattheywerenotindividuallyconsidered.)

FLUID-BEDDRI/HBI Circored (Lurgi) natural gasbased circulating fluidbed/bubblingbed

fineoreprocesswith100%HBIchargetoEAF(AppendixC-17) Circofer(Lurgi)finecoalandfineorecirculatingfluidbed/bubblingbed

with HBI charge to SAF and low-carbon, low-Si H.M. charge to EAF(AppendixC-18)

Finmet (VAI) multi-stage fluidizedbed fine ore process, natural gasbased,100%HBIchargetoEAF(AppendixC-19)

GenericIronCarbideProcess(torepresentallprocessvariationsand/orconfigurations)with100%ICchargetoEAF(AppendixC-20)

Generic Iron Carbide Process with 40% IC/60% Scrap charge to EAF(consideredtobeapracticallimitforchargingironcarbidetotheEAF)

OTHERPROCESSES SL/RN (Stelco-Lurgi) Rotary Kiln reduction process to produce 100%

spongeironchargetoEAFwithonlyrecycledScrap(AppendixC-21)



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Table2-4.3($100/mtScrapCostSensitivity)

SUMMARYOFRELATIVEOPERATINGCOSTS- IRONMAKINGPROCESENSITIVITY:$100.00/mtSTEELSCRAPPRICE

SEQ.NO.

PROCESS COSTPERNETMTLIQUIDSTEELORE,OTHERIRONUNITS

CONC.DELIVERED

PELLETIZING/BRIQUETTING

REDUCTION HOTMETALPROD.

PURCH

EAFSSHAFTFURNACEDRIPROCESSES:

C-1

C-2

C-3

C-4

C-5

C-6

100%SHAFTFURNACEDRICHARGETOEAF,1.0WT.%CARBON100%SHAFTFURNACEDRICHARGETOEAF,2.5WT.%CARBON100%STEELSCRAPCHARGETOEAF

30%SHAFTFURNACEDRI/70%SCRAPTOEAF,1.0WT.%DRICARBON30%SHAFTFURNACEDRI/70%SCRAPTOEAF,2.5WT.%DRICARBONHYLSASHAFTFURNACEWITHOUTREFORMER,HOTDRICHARGETOEAF

$64.31

$64.39

$21.33

$21.34

$64.31

$24.10

$24.13

$10.30

$10.31

$24.10

$49.99

$49.99

$16.87

$17.14

$42.76

HOTMETALVARIATIONSC-7

C-8

C-9

C-10

C-11

C-12

C-13

30%BLASTFURNACEHOTMETAL/70%SCRAPTOEAF,CO-PRODUCTCOKE30%BLASTFURNACEHOTMETAL/70%SCRAPTOEAF,N.R.COKE30%COLDPIGIRON/70%SCRAPTOEAF,4.5%CARBONPIG30%TECNOREDHOTMETAL/70%SCRAPTOEAF,WITHCO-GENERATION30%TECNOREDHOTMETAL/70%SCRAPTOEAF,WITHOUTCO-GENERATIONCOREX/MIDREXWITH60%HOTMETAL40%DRICHARGETOEAFHISMELTWITH32.7%HOTMETALTOCHARGETOEAF

$3.99

$4.07

$3.99

$41.73

$18.45

$10.29

$18.45

$23.46

$21.28

$21.28

$34.17 $10.67

$32.75

$29.41

$33.56

$23.86

$37.17

$75.27

$25.96

\\Da0002\01052901\common\DOE REPORTOCT2000\Section2.doc


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SUMMARYOFRELATIVEOPERATINGCOSTS- IRONMAKINGPROCSENSITIVITY:$100.00/mtSTEELSCRAPPRICE

SEQ.NO.


CONC.DELIVERED



PURCH

EAFSROTARYHEARTHFURNACES

C-14

C-15

C-16

REDSMELTHOTMETALWITHONLYRECYCLESCRAPCHARGETOEAFMAUMEEBRIQUETTEDRI/EAFWITHONLYRECYCLESCRAPCHARGETOEAFITMK3TOEAFWITHONLYRECYCLESCRAPCHARGETOEAF

$30.80

$32.41

$30.80

$31.78

$41.93

$38.46

$22.33

$32.60

$30.90

$38.68

FLUID-BEDDRI/HBIC-17

C-18

C-19

C-20a

C-20b

CIRCORED/HBI/EAFWITHONLYRECYCLESCRAPCHARGETOEAFCIRCOFER/HBI/SAF/EAFWITHONLYRECYCLESCRAPCHARGETOEAFFINMET/HBI/EAFWITHONLYRECYCLESCRAPCHARGETOEAFGENERICIRONCARBIDE/EAFRECYCLESCRAPCHARGETOEAFGENERICIRONCARBIDE/SAF/EAF60%SCRAPCHARGETOEAF

$37.95

$36.80

$37.11

$36.05

$14.42

$7.58

$15.08

$6.77

$78.22

$51.00

$79.72

$81.34

$32.54

$38.68

$17.01

OTHERPROCESSESC-21 SL/RNROTARYKILNWITHONLY

RECYCLESCRAPCHARGETOEAF$28.73 $49.07 $20.31



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SEQ.NO.


CONC.DELIVERED



PURCH


C-1

C-2

C-3

C-4

C-5

C-6



$64.31

$64.39

$21.33

$21.34

$64.31

$24.10

$24.13

$10.30

$10.31

$24.10

$49.99

$49.99

$16.87

$17.14

$42.76


C-8

C-9

C-10

C-11

C-12

C-13


$3.99

$4.07

$3.99

$41.73

$18.45

$10.29

$18.45

$23.46

$21.28

$21.28

$34.17 $10.67

$32.75

$29.41

$33.56

$23.86

$37.17

$75.27

$25.96



45/154


SEQ.NO.


CONC.DELIVERED



PURCH


C-14

C-15

C-16


$30.80

$32.41

$30.80

$31.78

$41.93

$38.46

$22.33

$32.60

$30.90

$38.68


C-18

C-19

C-20a

C-20b


$37.95

$36.80

$37.11

$36.05

$14.42

$7.58

$15.08

$6.77

$78.22

$51.00

$79.72

$81.34

$32.54

$38.68

$17.01





46/154



SEQ.NO.


CONC.DELIVERED



PURCH


C-1

C-2

C-3

C-4

C-5

C-6



$64.31

$64.39

$21.33

$21.34

$64.31

$24.10

$24.13

$10.30

$10.31

$24.10

$49.99

$49.99

$16.87

$17.14

$42.76


C-8

C-9

C-10

C-11

C-12

C-13


$3.99

$4.07

$3.99

$41.73

$18.45

$10.29

$18.45

$23.46

$21.28

$21.28

$34.17 $10.67

$32.75

$29.41

$33.56

$23.86

$37.17

$75.27

$25.96



47/154


SEQ.NO.


CONC.DELIVERED



PURCH


C-14

C-15

C-16


$30.80

$32.41

$30.80

$31.78

$41.93

$38.46

$22.33

$32.60

$30.90

$38.68


C-18

C-19

C-20a

C-20b


$37.95

$36.80

$37.11

$36.05

$14.42

$7.58

$15.08

$6.77

$78.22

$51.00

$79.72

$81.34

$32.54

$38.68

$17.01





48/154

Section3: IronmakingProcessDiscussionandGrouping

3.1 ProcessesConsideredandInitialScreeningThe goal of the Alternative Ironmaking Process Study was to analyze anumber of different ironmaking processes in a manner to evaluate theirindividual potential and to provide a consistent method for relativecomparison. Tocomparetheprocessesgiventhediversenatureofthetypesofironunitproductsthatwereproducedanddifferingpercentagesofthoseironunitsbeingutilizedtoproducesteel,itwasdecidedtonormalizeeachironmaking processby integrating it with an Electric Arc Furnace (EAF)steelmakingscenario. Anetproductionof1.0MMtonnesofRefinedLiquidSteel (as produced by the EAF/LRF process) was the normalized finalproduct on which the processes were compared. In this fashion variousproportionsoftheironproductionandvariousstatesoftheiron(e.g.ashotmetal,coldpigiron,directreducediron,etc.)couldbecomparedutilizingatypical commercial scenario.ItwastheintentfromtheoutsetoftheStudytocompareprovencommercialprocesswithevolvingorfirst-of-a-kindtechnologiesnotyetcommerciallyproven. Inaddition, conceptualprocessesor thosebeing researched anddevelopedintopotentiallyviabletechnologieswerealsogivenconsiderationin the Study. An initial screening and judgmental evaluation of theprocessesand potential production scenariosresulted inapproximately20Ironmaking production scenarios that were selected tobe evaluated andcomparedinmoredetail.The heat and massbalance modeling techniques discussed in Section 2-2were

utilized

to

develop

bases

for

Capital

and

Operating

Cost

estimates,

definition of cumulative emissions as representedby carbon gas (as CO2)andcumulativeelectricalpowerconsumption. To combinetheimpactsofCapital and Operating Costs, a simple Internal Rate of Return (IRR)calculationwasmadeforeachoftheprocesses. Theseand other variablesrelating to theIronand Steelmaking production scenariosfor each processwereusedasabasisforcomparisonandranking.



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3-1.1 ProcessesConsideredinInitialScreeningTYPE STATEOFDEVELOPMENT

SHAFTFURNACE BlastFurnace Corex Midrex Hylsa(HYLIII,HYLIVM,etc.)

Tecnored

ROTARYKILN SL/RNROTARYHEARTH Redsmelt Fastmet/Fastmelt Itmk3 Inmetco IronDynamics MauMeeFLUIDIZED

BED

Finmet Circored Circofer Nucor/ICH(Single-StageIC) Qualitech/Kawasaki(Two-StageIC) Procedyne(Multi-stageIC)OTHER (REACTOR ETC.) Hismelt Dios

Romelt

Gridsmelter Comet PlasmaRed AISI/Cyclone

ProvenCommercialProvenCommercialProvenCommercialProvenCommercialPilot

Scale

ProvenCommercialSemi-CommercialPilotScalePilotScaleSemi-CommercialSemi-CommercialSemi-CommercialSemi-CommercialSemi-CommercialSemi-PilotComponentDemonstrationDemonstrationSemi-PilotComponentPilotScalePilotScalePilot

Scale

Semi-PilotComponentSemi-PilotComponentSemi-PilotComponentPilotScale



50/154

Thedistinctionaboveis: ProvenCommercial Theprocessisoperatingcommerciallyin

morethanoneeconomically-viableinstallation.

Semi-Commercial Theprocessisundergoingstartupinafirst-of-a-kind commercialscaleinstallationorisstillinprocessdemonstrationphase.

Demonstration Theprocesshasoperatedatafirst-of-a-kindcommercialscale,butisnolongerbeingoperated.

PilotScale Theprocesshasbeenoperatedatanintegratedpilotscale.

Semi-PilotComponent Partsoftheprocesshavebeenoperatedatapilotscale.

In an initial evaluation and screening of the above processes, it wasdetermined thatsomeof the processescouldnotbedefinitivelycomparedsince not enough open information was available to close an energy andmass

balance.

Sparse

data

that

were

available

for

such

processes,

in

some

cases, did not indicate that there was a sufficient incentive to attempt toevaluateindetail.In other cases, the Ironmaking processes were not at a sufficient stage ofdevelopment or had a potential economic advantage to warrant furtherconsideration. An example of this was the production of Direct ReducedIron atahighcarboncontent (i.e. at2.5wt.%Cversus1.0wt.% C) in theshaft furnace (Midrex or Hylsa) processes. Changes in kinetics andreductiongas compositionrequirements to achieve the higher-carbon DRIproduct(someasironcarbide)didnotindicatethattherewasasignificantadvantage over the lower Carbon DRI product when used for EAF/LRFsteelmaking.Insomecases,inparticulartherotaryhearth,oxygenreactortypesandironcarbide processes, the Ironmaking processes of several Vendors weresufficientlysimilarastonotwarrantseparatetreatment. Therefore,atypicalIronmaking process oragenericprocesswasselected for the comparativeevaluation.



51/154

Itshouldbenoted thatanumberof OxygenReactor-based processeshavebeentestedandareunder investigation. Therewere typicallynotenoughdetailedoperatingand/orcompleteprocessdescriptionsavailabletodefinetheseprocesseswithenoughdetailtobeatthesamelevelofprecisionastheother,more-conventional, Ironmakingprocesses. TheHismeltprocesswasselectedforfurtherevaluationandisdeemedtobetypicalof thisgroup.Othersmayhavebetter,orlessfavorable,attributes,butcouldnotbefurtherexploredorcomparedwiththeotherIronmakingprocesses.Anumber of Plasma-based processeswerealso initially considered. TheAuthorhaspersonalprocessdevelopmentexperience inDirectPlasmaorereduction and/or melting processes. Lockwood Greene has also hadconfidential discussions with Plasma-Met Technology; thus there is aninternalbaseofinformationonsuchprocesses. However,theextraordinaryelectrical power requirements for these processes and low efficiency (notrigorouslydefined,butestimatedfromavailabledata)didnotindicateanycompetitive potential. As a group, these were not selected for furtherdefinitionorevaluation.An

abridged

list

of

Ironmaking

process

scenarios

for

further

evaluation

and

comparison was selected. These are the ones for which the detailedcomparisonsandrankinganalysesweredone(SeeSection4).3-1.2 ProcessScenariosSelected:SHAFTFURNACEDRIVARIATIONINCARBONANDSCRAPCHARGE BaseCase: 100%ShaftFurnaceDRI(i.e.Midrex)ChargetoEAF,1.0

wt.%DRI(RecycleSteelScrapOnly) 100%SteelScrapChargetoEAF(ForReferenceOnly) 30%ShaftFurnaceDRI/70%ScrapChargetoEAF(aCommonIndustry

Practice),1.0wt.%DRICarbon HylsaShaftFurnaceWithoutReformer(HYL IVM),HotDRIChargeto

EAF



52/154

HOTMETALVARIATIONS 30%BlastFurnaceHotMetal/70%ScrapChargetoEAF,Co-Product

Coke MiniBlastFurnaceComparison@30%H.M./70%ScrapChargetoEAF,

Co-ProductCoke 30%BlastFurnaceHotMetal/70%ScrapChargetoEAF,Continuous

Non-RecoveryCokewithCo-GenerationofElectricPower 30%ColdPigIron/70%ScrapChargetoEAF,4.5%Carbon 30%TecnoredHotMetal/70%ScrapChargetoEAF,4.5%Carbon

H.M.WithIntegralCo-GenerationofElectricalPower 30%TecnoredHotMetal/70%ScrapChargetoEAF,4.5%Carbon

H.M.WithoutCo-GenerationofElectricalPower Corex(VAI)/Midrexwith60%HotMetaland40%DRIChargetoEAF HiSmelt(ISCON)with34.5%HotMetalChargetoEAFROTARYHEARTHFURNACES

Redsmelt(Mannesmann)

Hot

Metal

With

Only

Recycle

Scrap

Charge

to

EAF

MauMeeR&EBriquetteDRI/EAFWithOnlyRecycleScrapChargetoEAF

ITMK3(MidrexRHF)toEAFWithOnlyRecycleScrapChargetoEAFFLUID-BEDDRI/HBI Circored(Lurgi)/HBI/EAFWithOnlyRecycleScrapChargeto Circofer(Lurgi)/HBI/SAF/EAFWithOnlyRecycleScrapChargeto

EAF Finmet(VAI)/HBI/EAFWithOnlyRecycleScrapChargetoEAF GenericIronCarbide(ICH)/EAFWithOnlyRecycleScraptoEAF

(RepresentsNucor/ICH,Qualitech/Kawasaki,ProcedyneProcesses) 40%IronCarbideCharge/60%ScraptoEAF(BelievedtobeMaximum

PracticalorFeasibleChargeRatio)



53/154

OTHERPROCESSES SL/RN(Stelco-Lurgi)RotaryKilnWithOnlyRecycleScrapChargeto

EAF

3-2: ProcessDescriptionsandFlowDiagramsThefollowingarebriefdescriptionsandpictorialProcessFlowDiagramsofSelectedIronmakingProcesses:3-2.1 SHAFTFURNACEPROCESSES:BlastFurnacePROCESSBACKGROUND:Theblast furnace process isbased upon a movingbed reduction furnacewhichreducesironorewith cokeandlimestone.Reductioniscarriedoutattypicalreductiontemperatures.Theprocessproducesliquidpigiron.PROCESSDESCRIPTION:The blastfurnaceprocessconsistsofweighingof theburden, chargingoftheblast furnace, hot product dispersal from theblast furnace and offgascleanupsystem. Theblastfurnaceisatallshaft-typefurnacewithaverticalstacksuperimposedoveracrucible-likehearth.Ironbearingmaterials(ironore, sinter, pellets, mill scale, steelmaking slag, scrap, etc.), coke and flux(limestone and dolomite) are charged into the top of the shaft. Ablast ofheatedairand also, inmostcases, agaseous, liquid or powdered fuel areintroducedthroughopeningsatthebottomoftheshaftjustabovethehearthcrucible.Theheatedairburnstheinjectedfuelandmostofthecokechargedinfromthetoptoproducetheheatrequiredbytheprocessandtoprovidereducing

gas

that

removes

oxygen

from

the

ore.

The

reduced

iron

melts

and

runs down to the bottom of the hearth. The flux combines with theimpuritiesintheoretoproduceaslagwhichalsomeltsandaccumulatesontopoftheliquidironinthehearth. Thetotalfurnaceresidencetimeisabout6to8hours. Thehotmetalproducedissenttoasteelmakingshoporapig-castingmachine.Theslaggoestoawater-spraygranulator,acryslagpitora slag dump. The gas from the top of the furnace goes through the gascleaningsystem,andthenaportiongoestofirethehotblaststoveswiththe

balancebeingusedinotherpartsoftheplant.Thedustisremovedfromthe\\Da0002\01052901\common\DOE REPORTOCT2000\Section3.doc Page6of50


54/154

gasinthecleaningsystemandgoestothesinterplant tobeagglomeratedforrecyclingbackintotheblastfurnace.PROCESSADVANTAGESProvenperformanceRawmaterialflexibility

BLASTFURNACEPLANTFLOWSHEET

EXHAUSTSTACK

FLUEGAS

LUMPIRONORE LIMESTONE

BLASTFURNACEDUST CATCHER

HOTMETALSUBMARINECAR

HOTSLAGtoDisposal

toBOForopenhearth

topigcastingmachine

ElectricPrecipitator

CokeOvens

SEPARATOR COOLINGTOWER

COKEPELLETSPREHEATED

AIR

CorexTheironoxidefeedtoaCorexreductionshaftisintheformoflumporeorpellets.Non-cokingcoalisusedintheCorexprocessasthestrengthofcokeneeded in the cohesive zone of the blast furnace to provide sufficientpermeabilitytothebedisnotrequired. Allothercokefunctionssuchasfuelsupply,basisfor thereductiongasgenerationand carborizationof the hotmetalcanbefulfilledaswellbynon-cokingcoal.Similartotheblastfurnaceprocess,thereductiongasmovesincounterflowtothedescendingburdenin the reduction shaft. Then, the reduced iron is discharged from thereductionshaftby screw conveyorsand transportedvia feed legs into themeltergasifier.ThegascontainingmainlyofCOandH2,whichisproduced

by the gasification of coal with pure O2 leaves the melter gasifier attemperaturesbetween 1000 and 1050C. Undesirable products of the coal



55/154

gasificationsuchastar,phenols,etc. aredestroyedand notreleased totheatmosphere.Thegasiscooledto800-850Candcleanedfromdustparticles.Afterreductionof the ironoreinthereductionshaft, the top gasiscooledand cleaned to obtain high caloric export gas. The main product, the hotmetalcanbefurthertreatedineitherEAForBOForcanbecastandsoldaspigiron.PROCESSADVANTAGESUseoflowcostnon-cokingcoal

IRONOREHOPPER

VOEST-ALPINECOREXPROCESSFLOWSHEETPELLETS/LUMPORE

COAL

OXYGEN

REDUCTIONSHAFT

MELTERGASIFIER

HOTMETALANDSLAG

EXPORTGASTOPGAS SCRUBBER

HOTGASCYCLONE

SETTLINGPOND

SCRUBBER

COOLINGGAS

DUST

MidrexShaftFurnacePROCESSBACKGROUND:The Midrex Direct Reduction process isbased upon a low pressure,movingbedshaftfurnacewherethereducinggasmovescounter-currenttothelumpironoxideoreorironoxidepelletsolidsinthebed. Thereducinggas(from10-20%COand 80-90%H2) is produced from natural gas usingMidrexs CO2 reforming process and their proprietary catalyst (instead ofsteamreforming).



56/154

Asinglereformerisutilizedinsteadofareformer/heatercombination. Thereformedgasdoesnotneedtobecooledbeforeintroductiontotheprocess.ThereisalsononeedforaseparateCO2removalsystem.TheprocesscanproducecoldorhotDRIaswellasHBIforsubsequentuseas a scrap substitute feed to a steelmaking melting furnace (SAF, EAF oroxygensteelmakingprocess).Over 50 Midrex Modules havebeenbuilt worldwide since 1969. Theyhavesuppliedover60%oftheworldsDRIsince1989.PROCESSDESCRIPTION:TheironoxidefeedtoaMidrex shaftfurnacecanbeintheformofpellets,lumporeoramixtureofthetwo(in0to100%proportions). Thesolidfeedis discharged into a feed hopper on top of a proportioning hopper thatevenlydistributesthesolidsintotheshaftfurnace.A dynamic seal leg keeps the reducing gas inside the furnace. The shaftfurnace

operates

at

low

pressure,

under

1bar

gauge,

which

allows

dynamic

sealstobeusedonthefurnaceinletanddischarge. Theironoreburdeninthe shaft furnace is first heated, then reduced by the upward flowing,counter-current reducing gas that is injected through tuyeres located in a

bustledistributoratthebottomof thecylindrical sectionoftheshaft. Theoreisreducedtoametallizationtypicallyintherangeof93%to94%bythetimeitreachesthebustlearea.Below thebustle area, it goes through a transition zone (with design toreduce agglomeration or lumping) and then reaches the lower conicalsectionofthefurnace. Lowercarbonreducediron(


57/154

The Midrex gas generation system consists of a CO2 reformer using theirowncatalyst. Thefeedtothereformerisamixtureofprocessgasrecycledfrom the furnace and makeup natural gas. The top gas leaving the shaftfurnaceatatemperatureof400to450Ciscooledanddustisremoved inatopgasscrubber.Abouttwo-thirdsofthegasisrecycledbacktotheprocess(processgas) and therestisusedasafuel.Theprocessgasiscompressed,mixedwithnaturalgasandispreheatedinthereformerrecuperatorbeforeenteringthetubesofthereformer.The reformed gas comprising of mostly CO and H2 exits the reformer atabout850Candpassesthroughcollectionheaderstothereformedgasline.TheratioofH2toCOiscontrolledatabout1.5to1.8,andreducingqualityat11to12forbestoperation.PROCESSADVANTAGES:World-widecommercialuseProvenperformanceRelatively-forgivingoperationRawmaterialflexibilityCO2 reformer eliminates need for steam system, reformed gas quench,reducinggasheatingandCO2removalsystem.

ShaftFurnace

Process Gas Co mpressors Top GasScrubber

Ma inAirBlower

Re former

Na turalGa s

FlueGas

EjectorStack

HeatRecovery

FeedGasDirect-Redu ced

Iron

Fue lGas

CombustionAir

FlueGa s

MIDRE XPR OCESS FLOWSHEE T Iron

Ox ide

Coo lingGasScr ubber

CoolingGasCo mpre ssor

Na turalGa s

Na turalGas



58/154

HYLSAIVMPROCESSBACKGROUND:TheHylsa4Mprocess isbased ona movingbed shaft furnace (similar toHYLIIIprocessbutwithoutareformer)whichreducesironorepelletsandlumpore,andoperatesattypicalreductiontemperaturesandintermediatereduction pressures. This process requires no reformer to generate thereducing gas as the reforming of the natural gas takes place inside thereductionreactorusingthemetallicironoftheDRIproductasthecatalyst.Theprocesscanproducecold/hotDRIaswellasHBI.PROCESSDESCRIPTION:Asbefore,theironoxidefeedtoaHylsa4Mfurnacecanbepellets,lump,oramixtureof the two(from0 to100%ofeither). HYL divides theprocessinto three primary units: Reduction system, DRI handling system andExternalcoolingsystem.The HYL 4M reactor operates at similar conditions to the other Hylsareactors (e.g. HYL III, etc.). The reactor has a cylindrical upper sectionwhere

reduction

and

reforming

reactions

take

place.

The

lower

part

is

conical with a rotary valve at the end to control the flow of solidsdischargingthereactor.Thestartingpointof thereductioncircuitisthefreshstreamofnaturalgasthatisusedasamakeupfortheprocess. Thisnaturalgas(desulfurizationisnot necessary,but is optional) is mixed with recycled gas and fed to ahumidifier, where the humidity of the total stream of reducing gas iscontrolledtoadjustthecarbondepositionrateontheDRIatthebottomofthereactor.Thereducinggasgoestothetopgasheatrecuperator,wheresensibleheatisrecovered from thereactor topgas. Thenthepreheated gasgoes toagasheaterwhere itstemperatureisincreased toabove900C. In the transferlinetothereactor,O2 isinjectedinordertohavesomepartialcombustionofthe reducing gas to increase its temperature to above 1020 C. This gas,upon introduction into thebottomof theHYL reactor, flowsupward intothereductionzonecountercurrenttothemovingbedofsolids. Inthelowerpartof thereductionzone,insitureformingreactionsarecarriedwhenthis



59/154

hotgascontactsthemetallicDRIproduct. ThemetallicironintheDRIactsasacatalystforthereformingreactions. Inaddition,thisoccursinparallelwiththefinalstageofreductionoftheironore.AsaresultsomeoftheDRIreactswiththecarbonandiscarburized(toFeC3)and thereissomeexcessfreecarbon.PROCESSADVANTAGES:Proven equipment performance (uses HYL II and HYL III reactortechnology)RawmaterialflexibilityNotsensitivetoSinnaturalgasororeNoreformerlowerCapitalcostsHigh-energyef

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