general knowledge on oil and gas
DESCRIPTION
Basic of general knowledge of Oil and Gas process, this the only little knowledge but you will find, how oil and gas process work.TRANSCRIPT
-
24/2/2015 GeneralKnowledgeonoilandgas
http://www.p3planningengineer.com/oil_N_gas/general.htm 1/7
General
Petroleumindustryisamainenergyindustry.Ithasahugechainofvaluefromupstreamtothedownstreamindustries,suchasoilexploration,oilextractionfromwellhead,storage,measurement,transportation,refinery,petrochemicalandchemicals.Sincetheindustryisallaboutdealingwithvarioushydrocarbonproducts,hydrocarbonindustryisanothernamefortheindustry.
Crudeoilfromthefieldreservoirusuallyhasgas,water,andsedimentinit.Theyarehighlyvariable,withnotwoexactlyalike.Onecrudemaybebrightgreenincolour,sweetsmellingandasfluidaswater.Anothermaybejetblackandhaveanunpleasantsulfuroussmell.Yetanothermaybepinkandstackupinapilewhenpouredonthegroundonahotday.Attheotherextreme,gascondensateiscolourlessandwillcompletelyevaporateifleftuncontained.Thespecificcharacteristicsofeachcrudereflectsitsuniqueblendofsizesandtypesofhydrocarbonmolecules,withthousandsofdifferentcompoundsinthemixture.
Thisextremevarabilityiswhythematerialwasnamedcrude.Itisindeedacrudematerial,beingmessy,unstableanddangeroustohandle.Essentiallyunstableinitsinitialform,crudemustberefinedbrokendownintoproductswiththespecificcharacteristicstohandlecertainjobswell,e.g.,gasolineanddieseltopowerengines,fueloiltoheathomes,etc.Thisistheroleofrefineries.
Verylittleofthecrudeisproducedbyrefinerowncompany.Instead,itisgenerallypurchasedontheopenmarket.Theindustryhasaveryefficientmarketoperatingbetweenproductionandrefining.Producerscancountongettingagoodpricefortheircrudeanywhereintheworldandrefinerscancountonbeingabletopurchasefeedstockatagoodprice.Crudeistradedfreely,oftenchanginghandsseveraltimesasittakesthemostefficientroutebetweentheproducingfieldsandtherefinery.
Crudeoilcanbetransportedfromtheproducingfieldtotherefineryinavarietyofconveyances.Foronshoreproduction,tanktrucks,railroadtankcars,andbargesoninlandwaterwaysareusedtosomeextent,butpipelinesarethedominantmodeoftransportation.Pipelinesarealsousedtobringproductionashorefromoffshorefieldslocatedreasonablyneartoland.
Formostexportoperationsaroundtheworld,marinetankersaretheonlychoiceavailable.ThebulkoftheenormousMiddleEastproduction,forexample,isshippedtoallpartsoftheworldintankers.
Mostofthewaterandsedimenthavetoberemovedbeforethecrudecanbesoldtoashipper.Also,gasandoilmustbeseparatedfromeachother.Therefore,surfaceprocessingfacilitieswithseparation,measurementandstoragearebuiltclosetotheoilfield.Also,therearespecialvesselscalledseparatorsandtreatersbeingemployedtoseparatefluidsandtoremoveemulsifiedwaterfromoil.
-
24/2/2015 GeneralKnowledgeonoilandgas
http://www.p3planningengineer.com/oil_N_gas/general.htm 2/7
Separatetheproducedfluidsintostremasofoil,gasandwaterforsaleanddisposal
Removefreewaterfromthewellbyknockouts
-
24/2/2015 GeneralKnowledgeonoilandgas
http://www.p3planningengineer.com/oil_N_gas/general.htm 3/7
Emulsion,amixtureofwaterandoil,tobeseparatedbywashtankwithflume
Refineries
Crudeoilcannotbeusedasafuelitself,becauseitcontainssuchabroadspectrumofmolecularsize.Tobepracticalasafuel,amaterialmusthaveknownburningcharacteristicssothatitcanbematchedwithanappropriateburnersystem(engine,boiler,etc.).
Thefirststepinarefineryistosplitcrudeintoseveralfractionsor"cuts"tocutthelargemoleculesofthecrudeintosmallervarioushydrocarbonproducts.Eachcutisconcentratingaparticularrangeofmolecularsizes.Forexample,oneofthecutsmightbelightgasesdescribedas"butanesandlighter"aheaviercutmightbekerosene.Thecutsaremadewithadistillationprocessthatemploysselectivevaporizationandrecondensation.
Thehighestvaluedpetroleumproductsarethe"whiteproducts",whichincludegasoline,diesel,jetfuel,andheatingoil.Productionofthese"middleofthebarrel"products,particularlygasoline,ismaximizedbyconvertingasmuchaspossibleofthelesservaluedgasesandtheheavier"bottomofthebarrel"materialstowhiteproducts.Thisisdonebyalteringthemoleculesasfollows:
Polymerizationisusedtocombinethesmallgasmoleculesintolarger,middleofthebarrel,moleculesCrackingisusedtobreakupthelarge,bottomofthebarrel,moleculesintosmalleronesIsomerizationaltersthearrangementofatomsinamoleculewithoutaddingorremovinganytheatoms
Theprocessesemployedtocutorrefinethecrudeincludeatmosphericdistillation,vacuumflashing,thermalcracking,catcracking,hydrocracking,gasplant,alkylation,catalyticreformingandblending.Roughly,thesearechainofprocess,meaningtheyieldofthepreviousprocessbecomesthefeedstockofthenextprocess,withdistillationbeingtheinitialprocessandblendingthefinalone.
DistillationTounderstandhowtheatmosphericdistillationtowerworks,letsusetapwaterbeingboiled(vaporized),thencooledsothatitrecondenses.Thisprocesscreatesdistilledwater,whichispurerthantheoriginalwaterbecauseonlytheH20moleculesvaporizedandleftthevessel.Thevariousnonvolatileimpuritiesinthetapwaterremainbehind,buildingupinconcentration,andeventuallyprecipitatingoutasasolidresiduewhenthevesselboilsdry.Thisprocessfunctionsthentoseparatethewaterfromtheimpurities.
Intheaboveexample,waterisboiledat100C(atsealevel).The100Ciscalledwater'sboilingpointandisspecifictothewatermolecule.Eachofthehydrocarbonmoleculeshasitsspecificboilingpoint,withthesmallerthemolecule,theloweritsboilingpoint.Thisisthekeytocuttingcrudeinadistillationtower.
Atmosphericdistillationistheinitialprocessinarefinery.Itsfractionatingtoweralargediameterverticalvesselwithmultipleinternalcontactortraysisthelargestintherefinery.Thecrudeisheated,vaporizingmostofit,then
-
24/2/2015 GeneralKnowledgeonoilandgas
http://www.p3planningengineer.com/oil_N_gas/general.htm 4/7
injectedintothebaseofthetower.Vaporsrisingthroughportsinthetrayscomeintocontactwithcondensedliquidsworkingdownwardthroughthecolumn.Thisinterchangecontinuallyvaporizessomeliquidandcondensessomegas,establishinganequilibriumthroughoutthecolumnwithheaviermaterialtowardthebaseandlightermaterialtowardthetop.Productcutsarecontinuouslyremovedfromthetowerthroughsidedrawsspacedalongitsverticallength.Thelocationofeachsidedrawisdesignedtotapaspecificboilingpointrangeofmaterial.
Mechanismofdistillingwater
-
24/2/2015 GeneralKnowledgeonoilandgas
http://www.p3planningengineer.com/oil_N_gas/general.htm 5/7
Distillationtower
Twotowersunderconstruction
BlendingBlendingoperationsarethefinalstep,combiningthevariousoutputsofalltheprocessesintothefinalproductsthataresold.Theblendingoperationhasamajorimpactonmanagingtherefinery.Itdetermineswhatfeedstocksandrunvolumesareneededsoeachofthevariousprocesseswillyieldtherequiredvolumesandspecificationsofproducts,suchasgasoline,dieselfuelandfurnaceoil.Theheavy,black,bottomofthebarrelresidualremainingafterprocessingcanbesoldasasphaltorblendedwithlightermaterialsandsoldas"resid"(residualfueloil).
Petrochemicals
Petrochemicalsarenonfuelcompoundsderivedfromcrudeoilandnaturalgas.Theindustryhasbeenbuiltontheextremereactivityofthecarbonatom.Thefeedstocksforpetrochemicalplantsareprovidedlargelybyrefineriesandincludegases,naphtha,kerosene,andlightgasoil.Naturalgasprocessingplantsarealsoasourceoffeedstock,providingnaturalgas,ethaneandLPG(liquefiedpetroleumgas).
-
24/2/2015 GeneralKnowledgeonoilandgas
http://www.p3planningengineer.com/oil_N_gas/general.htm 6/7
Petrochemicalplantsaretypicallybuiltadjacenttorefineriestobeneartheirsourceoffeedstock.Also,thereoftenarebyproductstreamscreatedintheplantsthatcanbestbeutilizedbyreturningthemtotherefineryforprocessing.Infact,theboundarybetweenthetwotypesofplantoftenbecomesblurredasprogressiveintegrationofbothfluidstreamsandoperatingpersonneltakesplaceforincreasedefficiency.Asaresult,severalverylargerefining/petrochemicalcomplexeshavedevelopedaroundtheworld.
Petrochemicalprocessesare,ingeneral,muchsmallerthanrefineryprocesses,butthereareexceptionslikeverylargeethyleneplants.Thesametoolsareusedasinrefiningheat,pressureandcatalystsbut,unlikerefineries,inorganicchemicalsareusedinsomeofthereactions.
It'snothardtovisualizeafuturewherecrudeoilandnaturalgascouldbecomeinsuchshortsupplythatburninghydrocarbonsasfuelwouldnolongermakesense.However,itwouldstillmakesensetomanufacturepetrochemicalsbecausetheyextractsuchincrediblevaluefromthehydrocarbonmolecule.
ProcessTool
Whethercruderefiningorpetrochemicalprocesses,thetoolsusedarethesame.Theyare:Heat(distillation):toexcitethemoleculesPressure:toretardvaporizationCatalyst:toassistthereactionbutnotparticipateinit
References
TheabovestuffistheexcerptfromThePetroleumIndustry,ANontechnicalGuidebyCharlesF.Conaway,Tulsa,OklahomaPublisher.1999.
SimplifiedChainofValue
Chain Feedstock(input) Process ExamplesofYield(output)
Refinery Crudeoil
Heat,pressure,catalysts
Kerosene,lightoil(jetoil,gasoline,diesel),Naphtha,Benzene,LPG,HFO,Bitomen,Sulfur
Petrochemical Fromoutputofrefineries Ethylene,polymers,PVC,Polyethylene,Polypropylene
ChemicalsOutputfrompetrochemicalorfromothersources
Fibres
Equipment
Thefollowingsarecommonequipmentfoundintheoilandgasplant.Absorber:CollectorthatactivelyabsorbsthelightraysBoiler:ProvidesteamheatCompressors:Compressorsdothesameforgasstreamsaspumpsdoforliquidscreatingapressuredifferentialthatmovesthegasthroughthesystem.Itisusedtoinjectlowpressureassociatedgasintohighpressurepipelines.Columns:FordistillationDeaerator:ToremoveairDrum:AcylindricalmetalcontainerforstorageofliquidsFurnace:ProvideheatforcrackingMeters:Monitoringandcontrolmeterssenseflowratesandpressuresinvesselsandpiping,alerttheoperatororautomaticallytaketheneededaction.Nozzle:ExhaustducttocontrolfluidflowexitfromanenclosedvesselPipeline:Pipelinestransportforbothgasandliquids.Theyprovidetheconduitsfortransportingproducedfluidsto
-
24/2/2015 GeneralKnowledgeonoilandgas
http://www.p3planningengineer.com/oil_N_gas/general.htm 7/7
andthroughthefacility.Theyareconstructedbyweldingtogetherjointsofsteelpipe.Mostpipelinesareexternallypaintedandinsulatedforprotectionfromcorrosionandabrasion.Piperack:SupportpipelinesPressurevessels:Thelargecylindricalpressurevesselsseenineveryproducingfacilityareessentiallyenlargedsectionsofapipeline.Theenlargementallowsfluidvelocitytoslow,providingtheretentiontimenecessaryforthefluidstogravitysegregate.Gravitysegregationistheprimarymechanismusedtoseparateoil,waterandgas.Pumps:Pumpspressurizeliquids,creatingapressuredifferentialthatmovesliquidsthroughthesystemfromlowerleveltothehigherlevel.Reactors:Adeviceusedtoforceacontrolledreactionwithagivensubstance.Themostcommonreactorisanozonereactor,whichforceswaterthroughapressurizedcolumnofanairozonemixtureTanks:Tanksarelargevesselsusedforvolumestorageofoilorwaterortoprovideretentiontimeforgravitysegregation.Althoughstoragetanksarenotconstructedtocontainpressure,afewouncesofgaspressureisnormallymaintainedtoexcludeair.Tower:SameascolumnValves:Theyeitherblocking(openorclosed)orcontrol(throttling).
[GeneralKnowledge][Terminologies][EPCPractice][PlantandInstallationPhotos][TowerErectionPhoto]