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PetroleumCokeGlossaryAAnodegradecokeAgradeofpetcokefromadelayedcoker(seesame)lowinmetalssuchasvanadium,nickelandironthatissuitableformakinggraphiteanodesforthealuminumsmeltingindustry.Ifthemetalscontentdoesnotqualifyasanodegradecoke,thenthecokeisgenerallyknownasfuelgrade(seesame).Thechoiceofwhetheracokemayqualifyasanodeorfuelgradeisdrivensolelybythecrudeslateofthecrudeunitupstreamofthecokerandthemetalscontainedtherein.Generallypresenceofanyshotcoke(seesame)andVolatility(seesame)10%areunacceptable.Sometimesanodegradeisalsoreferredtoascalcineablecoke(seesame)AAshTheresidueremainingwhenallofthecokeisburnedoff.Itismostlymetalsandsilica.BCCalcineablecokePetroleumcokethatqualifiestobecalcined,i.e.,generallynonshotandlowinmetalsthatwillqualifyforanodegrade.Calcineablecokeisgenerallyreferredtoastheavailablesupplytocalciners.Alsoknownasgreencoke(seesame).CCalcinedcokePetroleumcokeorgreencoke(seesame)thathasbeenprocessedinacalciner(seesame)CCalcinerAlargerotarykiln(similartoacementkiln)thatdrivesoffthemoistureandvolatilityofgreenorcalcineablecoke(seeeach)sothatthecokecanbeusedforaluminumanodes,ortitaniumdioxideapplications.Thekilnreceivesthecokeatthehigherendwherethecokeflowsdownhillasthekilnrotates.Atthesametimeheatedaircounterflowsuphillfromthelowerend,drivingoffthemoistureandvolatilematerialCCarbonrejectionCrudeoilcontainsawidevarietyofhydrocarbonmolecules,rangingfromasinglecarbonatom(methane)toverylongchainmolecules.Thelightermoleculesthatmakeupgasoline,jetanddieselcontainalowerratioofcarbontohydrogenthantheheaviermolecules.Inordertoconverttheheaviermoleculestolighterproducts,theheaviermoleculesmustnotonlybecracked,buttheexcesscarbonmustberemovedtoreducethecarbontohydrogenratioofthecrackedmaterial.CirculatingFluidizedBed(CFB)BoilerAtypeofboilerwherethesolidfuelisfluidizedinaverticalfurnace.Theadvantageforthepetcokeindustryisthat100%veryhighsulfurcokecanbeburned.Thesulfurisremovedbyadditionoflimestoneinthebedwhichformsaneasilyremovablecalciumsulfateash.CCokerArefineryprocessingunitthatconvertstheresidualoilfromthecrudeunitvacuumoratmosphericcolumnintogasoilthatcanbemadeintolightproducts(gasoline,jetanddiesel),weak(i.e.,lowenergycontent)fuelgasandpetcoke.Thereare3types:Delayed,Fluid,andFlexi(seeeach).Theseareallbasicallycarbonrejectionschemes(seesame).DDelayedcokerAtypeofcokerwhoseprocessconsistsofheatingtheresidualoilfeedtoitsthermalcrackingtemperatureinamultiparallelpassfurnace.Thiscracksthelongchainheavycarbonandhydrogenmoleculesoftheresidualoilintocokergasoilandpetcoke.Bothareinaliquefiedforminthemixtureasitleavesthefurnaceandentersthecokedrum.Inthedrum,thecokergasoilvaporizesandseparatesfromthemixture.Itisdirectedtoafractionationcolumnwhereitisseparatedintothedesirableboilingpointfractions.Theliquidcokesolidifiesinthedrumasitcoolsandthevelocityslowsdown.Afterthedrumisfullofthesolidifiedcoke,thehotmixturefromthefurnaceisswitchedtoaseconddrum.Whiletheseconddrumisfilling,thefulldrumissteamedtofurtherreducehydrocarboncontentofthepetcoke,andthenwaterquenchedtocoolit.Thetopandbottomheadsofthefullcokedrumareremoved,andthesolidpetcokeisthencutfromthecokedrumwithahighpressurewaternozzle,whereitfallsintoapitforreclamationtostorage.Largercokershaveseveralpairsoftandemdrums.DDemurrageContractsforrailcars,trucksandmarineshipsalwaysincludeaspecifiedtimelimitthattherespectivevehicleorshipwilltaketounloadorload.Thepenaltyfordelayingbeyondthetimeallowedisalsospecifiedineachcontract.Uponcompletionoftheactualloadorunload,thevehicleorshipownerpresentsthecustomerwithademurragebillspecifyingthetimedelaybeyondtheallowance,reasonsforitandthe$penalty.DDrymetricorshorttonAunitofmeasureforbillingpetcokeweight,whichreferstothegrosscokeweightadjustedforexcludingthecontainedmoisturecontent.Togetthismeasure,thecokemustbetestedformoisturecontent(seesame).Calcineablecoke(Seesame)isfrequentlymeasuredintheseunits.AlsoseeWetmetricton.EEnergycontentTheenergycontentofcoalandcokeisusuallyspecifiedineitherBTU/lborKcal/kg.Itismeasuredinacalorimeterthatliterallyignitesthetestsampleandmeasuresthetemperatureriseofthewaterbathsurroundingit.FFlexicokerTheflexicokeraddsathirdvessel,agasifier,tothefluidcokertogasifythepurgecokeintoaweakfuelgas.Cokeismadein3areas:purgecokefromtheheater,andbothlargerandsmallerrecoveredcokefinesfromtheweakgasscrubbers.Itisa“flexible”cokerinthatthegasifiercanberuntomakeeithermorecokeormoreweakfuelgas.FFluidCokerAfluidcokerproducesmorelightproductyieldandlesscokebutthecokeishigherinmetalsandharderthanadelayedcoker.Theprocessisacontinuousfluidizedbedconsistingofareactorandaburnervessel.Feedissprayedontoseedpelletsofcokeinthereactorwhereitiscoked.Purgecokeisdrawnofftheburnervessel.FFuelgradecokePetcokethatcompeteswithsteamcoalasfuelforafurnace,boilerorcementkiln.Ifthecokecontainslowmetals,itmayqualifyasanodegrade(seesame).Thechoiceofwhetheracokermakesfuelgradevsanodegradeisdictatedsolelybythecrudeslateandthemetalscontenttherein.GGreencokeUsuallyreferstocalcineablecoke,i.e,potentialanodequalitycokethatstillcontainsmoistureandvolat