油气储运专业英语(英汉互译)

./Chapter1OilandGasFields第1章油气田1.1AnIntroductiontoOilandGasProduction1.1石油和天然气生产的介绍Thecomplexnatureofwellstreamsisresponsibleforthecomplexprocessingoftheproducedfluids<gas,oil,water,andsolids>.Thehydrocarbonportionmustbeseparatedintoproductsthatcanbestoredand/ortransported.Thenonhydrocarboncontaminantsmustberemovedasmuchasfeasibletomeetstorage,transport,reinjection,anddisposalspecifications.Ultimatedisposalofthevariouswastestreamsdependsonfactorssuchasthelocationofthefieldandtheapplicableenvironmentalregulations.Theoverridingcriterionforproductselection,construction,andoperationdecisionsiseconomics.油气井井流的复杂性质,决定了所产流体<气、油、水和固体>的加工十分复杂。必须分出井流中的烃类,使之成为能储存和/或能输送的各种产品;必须尽可能地脱除井流中的非烃杂质,以满足储存、输送、回注和排放的规。各类废弃物的最终处置取决于各种因素,如油气田所处地域和所采用的环保规定等。经济性是决定油气田产品设计、建筑和操作决策的最重要准则。Fig.1-1isacomprehensivepictureoftheindividualunitoperationscarriedoutinfieldprocessing.Allthevariousmodulesshownwillnotallbepresentineverysystem.Furthermore,themodulesusedinagivenapplicationmaynotbearrangedintheexactsequenceshown,althoughthesequenceis,ingeneral,correct.Theselectionandsequencingofmodulesisdeterminedduringthedesignphaseoffielddevelopment.图1-1表示在矿场进行的各种单元操作的综合图。在各系统不一定有图1--}所示的全部操作模块。尽管图中所示的加工顺序通常是正确的,但在某一特定使用情况下,模块的布置可能会与图中所示的顺序不同。在油气田开发设计阶段确定模块的选择和排列顺序。AsshowninFig.1-1,theindividualphases<gas,liquidhydrocarbon,liquidwater,andsolids>shouldbeseparatedfromeachotherasearlyaspractical.Individualstreamscanthenbetreatedwithlesstechnicaldifficultyandmoreeconomically.HartleyandBinJadid<1989>illustratehowlabandfieldtestsperformedbeforeconstructioncanidentifyandminimizefutureproductionandprocessingproblemssuchasscaling,foaming,emulsionformation,waxdeposition,andhydrateformation.Processingoftheseparatedstreamsisnowreviewedbrieflybecausemanyoftheindividualunitoperationsarediscussedindetailinsubsequentchapters.如图1-1所示,应尽早将各股流体<气、液态烃、液态水和固体>分离。这样,单独处理各股流体时,技术难度较小,也较经济。Hartley和BinJadid<19$9阐明了在建设前进行的室和现场试验可以发现并减少将来在生产和加工中可能出现的问题,如结垢、发泡、形成乳状液、结蜡以及生成水合物等,现在简要介绍被分离的各股流体的加工,在后续章节中将详细讨论其中的许多单元操作。1.1.1GasProcessing1.1.1气体加工AsshowninFig.1-1,gasprocessingbeginswithtreating,ifnecessary,toremovetheacidgases-hydrogensulfideandcarbondioxide.Bothgasesareverycorrosivewhenliquidwaterispresentandhydrogensulfideismosttoxic.Environmentalregulationsalmostalwaysprohibitthereleaseofsignificantamountsofhydrogensulfidetothesurroundings.Conversiontoelementalsulfurisbecomingincreasinglynecessary.如图1-Z所示,气体加工<若需要>从脱除酸气<H2S和CO2>开始。当存在液态水时,这两种气体有极强的腐蚀性,而且H2S极具毒性。环保法规几乎都禁止向周围环境排放大量H2S,而且正愈来愈多地要求将H2S转变为元素硫。Gassweeteningusuallyusesaqueoussolutionsofvariouschemicals.Therefore,sweeteningwillprecededehydration.Dehydrationisoftennecessarytopreventtheformationofgashydrates,whichmayplughigh-pressureprocessingequipmentorpipelinesathighpressureandattemperaturesconsiderablyhigherthan32°F<0°C>.天然气脱酸气常使用各种化学剂的水溶液,因而脱酸气应在气体脱水之前进行。为防止生成气体水合物,常需进行脱水。在高压和比32°F<0℃>高的温度下,水合物可能堵塞高压工艺设备和管线。Gasthatcontainsconsiderableamountsofliquefiablehydrocarbons<ethaneorpropaneandheavier>canproducecondensateuponcompressingorcooling.Thecondensatemaycausedifficultyinpipeliningorsubsequentprocessing.Fieldprocessingtoremovethesenatural-gasliquids<NGL>,sometimesreferredtosimplyascondensate,maybeeconomicalormayberequiredtomeetahydrocarbondew-pointspecification.Inremotelocationssuchprocessingisgenerallyavoidedifpossible.Recoveredcondensatemay,inturn,havetobestabilizedbyremovingdissolvedgaseouscomponentstoobtainatransportableproduct.含有大量可液化烃类<C2+或C3+>的气体,在压缩或冷却时一可能产生凝析油。凝析油会给管输和后续加一带来困难。在矿场脱除这些天然气液体<NGL,有时简称为凝析油>可能是经济的,或为满足烃露点规定所必需的。在边远地区应尽一量避免脱除凝析油的工作。回收的凝析油必须进行稳定,脱除溶解气组分,以获得可输送的产品。1.1.2OilProcessing1.1.2原油加工Afterfreewaterremoval,producedoiloftencontainsexcessiveresidualemulsifiedwater。].Treating,alsocalleddehydration,isrequiredtoreducethewatercontenttoavalueacceptablefortransportationorsales.Dehydrationshouldbeaccomplishedusingthemosteconomiccombinationoffourfactorsortechniques;namely,residencetime,chemicaladdition,heat,andelectrostaticfields.Dilutionwatermustoccasionallybeaddedtoreducethesaltcontentoftheresidualemulsion<i.e.,thesalescrudeoil>toasuitablylowlevel.IntheUnitedStates,desaltingisusuallyperformedintherefinery；overseas,desaltingissometimesperformedinthefield.脱除游离水后,生产的原油常含有过量的残余乳化水。含有过量残余乳化水的原油需要进行处理<也称脱水>,将水含量降至运输和销售允许的限度。可应用四种技术的最经济组合实施脱水,即停留时间、化学添加剂、加热和静电场。有时还必须掺人稀释水,将残余乳状液<即销售原油>的盐含量降低至合理的低浓度。美国,脱盐常在炼厂进行；美国以外地区,脱盐有时在矿场进行。Hydrogensulfideincrudeoilislimitedtoreducehandlingandtransportationdifficultiesbecauseofitsextremetoxicityandcorrosiveness.Gasstrippingorheatingisusuallyusedforhydrogensulfideremovalorsweeteningasisdiscussedlatterly.由于H2S具有剧毒和腐蚀性,故应限制原油H2S的含量,以降低原油装卸、沛在和输送过程的困难。如在后续容中讨论的那样,常用气提或加热方法脱除原油的H2S,或使其"甜化"。Crudeoilstabilizationreferstoloweringthevaporpressuretoavaluethatwillallowsafehandlingandtransport.Vaporpressurecontrolisobtainedbystageseparation,reboileddistillation,oracombinationofthetwo.Duringstabilizationsomeofthemorevolatilehydrocarbonsareremovedasvaporandthisgasphaseentrainshydrogensulfideandothervolatilesulfurcompoundsfromthesourcrudeoil.Additionalsweeteningmaynotberequired.原油稳定是指将蒸气压降低至某一数值,在该蒸气压下原油可安全地装卸、储存和运输。多级分离、再沸蒸馏或多级分离与再沸蒸馏相结合,来控制原油蒸气压。在稳定过程中,某些挥发性强的烃类成为蒸气从原油分出,这种烃类气体还从酸性原油带出H2S和其他挥发性强的硫化物。原油也可能不需要专门的脱硫或"甜化"处理。1.2BriefDescriptionofCrudeOilSurfaceTreatment1.2原油地面处理简介Wellfluidsareoftenacomplexmixtureofliquidhydrocarbons,gas,andsomeimpurities.Itisnecessarytoremovethegasandsomeimpuritiesfromtheliquidhydrocarbonsbeforetheyarestored,transported,andsold.Liquidhydrocarbonsandobjectionableimpuritiesmustalsoberemovedfromnaturalgasbeforethegasgoestoasalesline.Impuritiesthatmightbefoundinsomewellstreamsarehydrogensulfide,carbondioxidefreewater,watervapor,mercaptans,nitrogen,helium,andsolids.Nearlyallofsiteimpuritiescausevarioustypesofoperatingproblems.井流通常是液态烃、气体和某些杂质的复杂混合物。在液态烃储存、输送和销售前,必须从浪态烃中脱除气体和某些杂质。气体进人销售管道前,也必须从天然气中脱除液态烃和有害杂质.在某些并流中,可能存在的杂质是硫化氢、二氧化碳、游离水、水蒸气、硫醇、氮、氦和固体杂质。几乎所有的杂质都会引起各种操作问题。Theseparationofnaturalgas,liquidhydrocarbons,andimpuritiesisaccomplishedbyvariousfield-processingmethods,dependinguponthecompositionofthewellstreamandthedesiredendproduct.Thosemethodsincludetime,chemicals,gravity,heat,chemicalsorelectricalprocesses,andcombinationsofthese.根据井流的组成和要求的终端产品,可采用各种现场加工方法实现天然气、液态烃和杂质的分离。这些方法包括时间、化学药品、重力、热、机械或电加工,以及上述方法的综合运用。1.2.1Separators1.2.1分离器Separationofwell-streamgasfromfreeliquidsisthemostcommonandsimplestformoffieldprocessing.Theequipmentmostwidelyusedforthistypeofprocessingisreferredtoasaseparator.Theseparationofnaturalgasfromliquidsand/orimpuritiesmaseparatorcombinesgravity,time,mechanicalprocesses,andoccasionallychemicals.液体与井流气的分离是现场加工最普遍和最简单的方式。这类加工中最常用的设备称为分离器。在分离器,从液体和/或杂质中分出天然气时可综合使用重力、时间和机械方法,偶尔也采用化学药剂。Thesizeoftheseparatorisdependentuponrateofflowofthenatural^asand/orliquidsgoinginthevessel.Theoperatingpressureofthevesselisdependentuponthepressureofthegassalesline,theflowingpressureofthewell,andoperatingpressuredesiredbytheleaseoperator.分离器的大小取决于进人分离器的天然气流量和/或液体流量。容器的操作压力取决于气体销售管线的压力、井的流动压力和矿场操作人员要求的操作压力。Separatorsarebuiltinvariousdesigns,suchasvertical,horizontalandspherical.Theinternalsofthevessel.toaidinthemechanicalseparationofthegasandliquids,areofaspecialdesign,dependinguponthemanufacture.Althoughmostseparatorsaretwo-phaseindesignseparatingthegasandliquids,theycanbebuiltthree-phaseloseparatenaturalgas,liquidhydrocarbons,andfreewater<Fig.1-2>.分离器有各种不同设计,如立式、卧式和球形分离器。促进气液机械分离的容器部构件是由制造商专门设计的。尽管设计中多数分离器只分离气液两相,但能制造分离天然气、液态烃和游离水的三相分离器<图1-2>。1.2.2OilTreating1.2.2原油处理Whencrudeoilisproduced,variousamountsofgas,water,andotherimpuritiesaremixedwiththeoil.Someofthismixturecomesasfreeoil,someasfreewater,andsomeasahomogeneousmixtureknownasanemulsion.Thegas,water,andotherimpurities<knownasbasicsedimentandwater>mustberemovedbeforesellingtheoil.Thisseparationprocessiscalledoiltreating.采出的原油会混有不同数量的气、水和其他杂质。这种混合物中有些为原油,有些为游离水,有些为被称作乳状液的均匀混合物。原油销售前必须脱除气体、水和其他杂质<称为底部沉积物和水>。这种分离过程称为原油处理。Treatingsystemsareimportantpartsofleaseequipment.Experienceinaparticularfieldorareaisvaluableindeterminingthebestequipmentfortheapplication.处理系统是矿场设备的重要组成部分。在确定原油的最佳处理设备时是有价值的,在特定油田和地区的经验十分重要。Inselectingatreatingsystem,anumberoffactorsshouldbeconsideredtodeterminethemostdesirablemethodoftreatingthecrudeoiltopipelinerequirements.Someofthesefactorsare:为了确定原油的最佳处理方法,使之满足管输要求,在选择处理系统时应考虑许多因素。其中的一些因素是：<1>Tightnessofemulsion.〔1乳液的牢固程度。<2>Specificgravityoftheoilandproducedwater.〔2油和采出水的相对密度。<3>Corrosivenessoftheoil,gas,andproducedwater.〔3油,气,和采出水的腐蚀性。<4>Scalingtendenciesoftheproducedwater.〔4采出水的结垢趋势。<5>Quantityoffluidtobetreatedandpercentofwaterinthefluid.〔5需处理的流体数量和流体的水含量。<6>Availabilityofsaleslineforthegas.〔6是否有气体销售管线。<7>Desirableoperatingpressurefortheequipment.〔7设备所需的操作压力。<8>Paraffin-formingtendenciesofthecrudeoil.〔8原油的结蜡倾向。Oil-fieldemulsionsareusuallyofthewater-in-oiltype;however,afewoftheemulsionsareoil-in-watertypeandarecalledreverseemulsions.Emulsionsarecomplexandeachshouldbeconsideredindividually.油田乳状液通常为油包水型,个别情况为水包油型,并称为反相乳状液。乳状液非常复杂,对每一种乳状液都应单独考虑。Inordertobreakacrudeoilemulsionandobtaincleanoil,itisnecessarytodisplacetheemulsifieranditsfilm.Thisbringsaboutthecoalescenceofdropletsofwaterandfurnishesameansandtimeperiodofundisturbedsettlingofthecoalescedwaterdrops.Thereareseveralmethodsusedinconjunctionwithoneanotherto"treat"anoilemulsion.为使原油乳状液破乳并得到净化油,需要一置换乳化剂及其薄膜。这样可促使水摘聚结、并并为聚结水滴提供无干扰的沉降时间和沉降方法。处理原油乳状液有多种彼此组合的方法。1.2.5VerticalTreaters1.2.5立式处理器Themostcommonlyusedsingle-wellleasetreateristheverticaltreaterasshowninFig.1-5.Flowentersthetopofthetreaterintoagasseparationsection.Caremustbeexercisedtosizethissectionsothatithasadequatedimensionstoseparatethegasfromtheinletflow.Ifthetreaterislocateddownstreamofaseparator,thischambercanbeverysmall.Thegasseparationsectionshouldhaveaninletdiverterandamistextractor.图1-5所示的立式处理器是最常用的矿场单井处理器。井流进入处理器顶部的气体分离段。在确定该段尺寸时,应使其有有足够的空间寸来从井流中分离出气体。如果处理器位于分离器下游,气体分离段可以很小。气体分离段应有一个入口分流器和捕雾器。Theliquidsflowthroughadowncomertothebaseofthetreater.whichservesasafree-waterknockoutsection.Ifthetreaterislocateddownstreamofafree-waterknockout,thebottomsectioncanbeverysmall.Ifthetotalwollstreamistobetreatedthissectionshouldbesizedfor3to5minutesretentiontimeforboththeoilandthewatertoallowthefreewatertosettleout.Thiswillminimizetheamountoffuelgasneededtoheattheliquidstreamrisingthroughtheheatingsection.Theendofthedowncomershouldbeslightlybelowtheoilwaterinterfaceto"waterwash"theoilbeingtreated.Thiswillassistinthecoalescenceofwaterdropletsintheoil.液体通过降液管流至处理器底部,该段为游离水分离段。如果处理器位于游离水分离器下游,则该段可以很小。如果要处理全部井流,以油、水在该段都停留3-5min来确定该段的大小,以便游离水沉降。分出游离水后,将减少向上通过加热段液流所需的加热燃料气为了用水洗涤被处理的原油,降液管的底端应略低于油水界面。水洗将促进原油水滴的聚结。Theoilandemulsionrisesovertheheaterfire-tubestoacoalescingsectionwheresufficientretentiontimeisprovidedtoallowthesmallwaterparticlesintheoilcontinuousphasetocoalesceandsettletothebottom.原油及其乳状液上升,通过加热器火筒至聚结段。聚结段可提供足够的停留时间,便连续相原油的水滴聚结并沉降至处理器底部Treatedoilflowsouttheoiloutlet.Anygas,flashedfromtheoilduetoheating,flowsthroughtheequalizinglinetothegasspaceabove.Oillevelismaintainedbypneumaticorleveroperateddumpvalves.Oil-waterinterfaceiscontrolledbyaninterfacecontroller,oranadjustableexternalwaterleg.处理后的原油从油出口流出。由于加热,从原油闪蒸出的气体通过平衡管线流入处理器顶端的气体空间。气动或连杆操作的出油阀可控制油面液位,由界面控制器或外部可调出水管线控制油水界面。Thedetaileddesignofthetreater,includingthedesignofinternals<manyfeaturesofwhicharepatented>shouldbetheresponsibilityoftheequipmentsupplier.处理器及其部构件<构件的许多特点都有相应专利>的详细设计应由设备供应商负责。1.2.6StabilizationandSweeteningofCrudeOil1.2.6原油的稳定和脱酸Dissolvedgasinthewellheadcrudeoilmustberemovedtomeetpipeline,storage,ortankerReidvaporpressure<RVP>specifications.Whentheoilisessentiallyfreeofdissolvednaturalgas,or"dead"thenitcanbestoredinaventedtankatatmosphericpressuresubject,ofcourse,toemissionregulations.Thepresenceofthemostvolatilehydrocarbons<C1,C2,C3,etc.>increasestheRVPdramatically.Removalofthesedissolvednatural-gascomponentsiscalledcrudeoilstabilization.必须脱去井口原油的溶解气,以满足管道、储存或油轮运输对雷特蒸气压的技术规定。只有当原油基本上没有溶解天然气<或称"死油">并满足废气排放规定时,才能储存在常压通风储罐。原油存在挥发性极强的组分<C1,C2,C3,等>时,将极增加雷特蒸气压。脱除这些溶解的天然气组分称为原油稳定。TheRVPisusuallysetintherangeof10-12psia,whichgenerallyyieldsatruevaporpressure<TVP>—or,moreproperly,abubblepointpressureat100。F-ofslightlyhighervalue,13—15psia.OtherimportantspecificationsthatmustbemetareBS&WandH2Scontent.Hydrogensulfidespecificationsareusuallyintherangeof10-60ppm<Moins,1980>.通常,设定的雷特蒸气压围为14--12psia,雷特蒸气压<RVP>一般比真实蒸气压〔TVP,确切的说是1440F下的泡点压力略低,真实蒸气压约为13--15psia。对原油的其他重要规定还包括水和悬浮固体含量以及H2S含量。对H2S含量的规定围常为10-60ppm〔Moins,1980。Oftenaconsiderableamountofgasisdissolvedincrudeoil.Hydrocarbonsareusuallyworthmoreasliquid<i.e.,inthecrudeoilphasethaninthevaporornaturalgasphase>,evenwhenassociatedgasisusedforLNG[I8]orwhenthegasissoldandcondensateisextracted.原油常溶有相当数量的气体。液态烃类的价值一般较高<即烃类在原油比在蒸气或天然气的价值高>,即使是伴生气用作制造液化天然气,或从气体回收凝析油、销售气体,其价值也低于原油。AsecondpossiblebenefitofspikingcrudeoilwithlighthydrocarbonsisthepotentialforincreasedpriceduetoincreasedAPIgravity.Thisincreaseisusuallysmall,however—lessthanonedegreeAPI—andthepriceincreaseisalsomodest,about10cents/bblper°APIincrease.用轻烃掺入原油的另一好处是,由于API相对密度增加,可提高原油售价。相对密度的增加一般很小,小于10API,而价格也温和地增加。每增加10API,每桶原油约增加10美分。Aspreviouslydiscussed,sourcrudesdocontainsulfurcompoundsingeneralandhydrogensulfideinparticular,Stabilizationmustalsoremovethevolatilesulfurcompoundstomeetsalesortransportspecifications.如前所述,酸性原油一般总含有硫化物,特别是含有H2S。稳定处理时也必须脱除挥发性硫化物,以满足销售和输送的技术要求。Theeconomicgoalofstabilizationistomaximizestock-tankoilrecoverywhilemeetinvaporpressureandH2Scontentspecifications,aswellasBS&W.Butanesincreasethevaporpressureofcrudeoilconsiderably,sincethetruevaporpressureofi-C4andn-C4are72.6and52.1psia,respectively.ControlofthebutanecontentcontrolstheRVPandTVP.在满足蒸气压、H2S和固体悬浮物及水含量的技术要求下,使矿场储罐原油收率最高是原油稳定的经济目的。由于正、异丁烷的绝对真实蒸气压分别为72.6psi和52.1psi,故丁烷对原油蒸气压的增加有重要影响。控制丁烷含量就控制了RVP和TVP。ThetechnicalgoalofstabilizationistoremoveC1,C2,andC3ascompletelyaspossiblewhileleavingthemaximumamountsofC4<andC5andheavier>inthecrudeoil.稳定的技术目的是尽可能地完全脱除C1,C2,和C3。并在原油留下尽可能多的C4,〔以及C5和重于C5的组分。Crudeoilcanbestabilizedbypassingitthroughaseriesofflashdrumsorvapor-liquidseparatorvesselsatsuccessivelylowerpressures.Traytowerswithreboilers,alternativelyorinconjunctionwithseparators,arealsoused,thoughlessoften.让原油通过一系列逐步降压的闪蒸罐或气一液分离器可以使原油稳定,也可以使用带重沸器的板式塔或采用板式塔与分离器结合的方式使原油稳定,但使用较少。Stabilizationcanalsosweetenthecrudebecausethechiefsulfur-containingorsourcontaminant,H2S,hasaboilingpointof-76.5T-intermediatetothatofethaneandpropane.Incidentally,dissolvedradongaswillalsoberemovedwiththelighthydrocarbons.itsboilingpointis-79.2°F.Radonradioactivitymustbeconsideredverycarefully.由于主要的含硫或酸性杂质为H2S,它的沸点为一76.5°F,介于乙烷和丙烷之间,故稳定过程也使原油脱酸。顺便提及,氡的沸点为一79.20F,在稳定过程中溶解在原油中的氡气也会随轻烃一起从原油脱除。必须十分谨慎地对待氡的放射性。So-calledsourcrudeoilcontainsH2Sandothersulfur-containingcompounds.EvensmallamountsofH2Smakethecrudeoilextremelytoxicandcorrosive.Theothersulfurcompoundsarefarlesstoxicandnotsoaggressivelycorrosive,eventhoughsomehaveequallystrongodors.ThepresenceofliquidwaterexacerbatesthecorrosionasdoesCO2.PersonnelsafetyandequipmentprotectionrequirethatH2Sand<toalesserextent>othersulfurcompoundsberemoved.所谓酸性原油,是指含有H2S和其他含硫化合物的原油。即使含少量硫化氢,也使原油具有很强的毒性和腐蚀性。尽管某些硫化物有与H2S相同的强烈气味,但这些硫化物的毒性和腐蚀性远低于H2S。与CO2类似,液态水的存在也会激化腐蚀。从人员安全和设备防护的角度来看,应脱除H2S,并在某种程度上同时脱除其他硫化物。1.3TreatingOilFieldEmulsions1.3油田乳状液的处理1.3.1TheoryofEmulsions1.3.1乳状液理论Anemulsionisacombinationoftwoimmiscibleliquids,orliquidsthatdonotmixtogetherundernormalconditions.Oneoftheliquidsisspreadout,ordispersed,throughouttheotherintheformofsmalldroplets.Thesedropletscanbeofallsizes,fromfairlylargetoverysmall.Sometimesdropletsaresosmallthatmorethanfiftyofthemcouldbeplacedontheheadofapin.Astableemulsionisanemulsionthatwillnotbreakdownwithoutsomeformoftreating.乳状液是两种不相溶液体或在正常条件下不能混合在一起的多种液体的混合物。其中,一种液体以小液珠形式完全分散于另一种液体。这些液珠的粒径是各不相同的,从很大至非常细小。有时,液珠小至可在一枚大头针端部放置50多个液珠。Threeconditionsarenecessaryfortheformationofastableemulsion.稳定乳状液是一种不采用某种处理方法不能破乳的乳状液。形成稳定乳状液必须具备三个条件:<1>Theliquidsmustbeimmiscible.〔1各液体必须是互不相溶的;<2>Theremustbesufficientagitationtodisperseoneliquidasdropletsintheother.〔2需要有足够的搅动,使一种液体成为液珠分散于另一种液体;<3>Theremustbeanemulsifyingagent,oremulsifier,present.〔3需要有乳化剂。Toformastableemulsionofcrudeoilandwater,anemulsifyingagentmustbepresent.Emulsifyingagentscommonlyfoundinpetroleumemulsionsincludeasphalt;resinoussubstances;oilsolubleorganicacids;andotherfinelydividedmaterialsthataremoresoluble,wettable,ordispersableinoilthaninwater.Somefinelydividedsolidsareiron,zincandaluminumsulfates,calciumcarbonate,silica,andironsulfide.Eachoftheseemulsifiersusuallyoccursasafilmonthesurfaceofthedisperseddroplets.为形成原油和水的稳定乳状液,必须要有一种乳化剂。在石油乳状液发现的乳化刑通常包括沥青、树脂物质、油溶性有机酸以及那些更易溶解于油中、易为油所润湿或易在油中分散的细颗粒物质。某些细颗粒固体为铁、锌和硫酸铝、碳酸钙、硅和硫化铁。上述每种乳化剂一般都会在分散液珠表面形成薄膜。Inanemulsion,theliquidthatisbrokenupintodropletsisknownasthediscontinuous,dispersedorinternalphase.Theliquidthatsurroundsthedropletsisknownasthecontinuousorexternalphase.Anemulsionofoilandwatermayhaveeitheroilorwaterasthedispersedphase,dependingonthecharacteristicsoftheemulsifyingagent,butinmostcasesitisthewaterthatisdispersedasdropletsintheoil.乳状液破碎为液珠的液体称为一作连续相,也称分散相或相。液珠周围的液体称为连续相或外根据乳化剂的性质,油水乳状液油或水均可成为分散相,但多数情况下水以水珠分散于油中。Anoil-wateremulsionmaycontainfromatraceto90percentormorewater.Also,anemulsionmaybetight<difficulttobreak>orloose<easytobreak>.Whetheranemulsionistightorloosedependsonseveralfactors,whichincludethepropertiesoftheoilandwater,thepercentageofeachfoundintheemulsion,andthetypeandamountofemulsifierpresent.油水乳状液的水含量可从含微量水<痕迹>至90%或90%以上.乳状液可能很牢固<难于破乳>,也较疏松<易于破乳>。乳状液破乳的难易取决于若干因素,包括油水性质、乳状液油和水的百分含量、乳状液乳化剂的类型和数量。Occasionallyemulsionsproducedfromsomefieldsarethereversetypeinwhichtheoilistheinternalphaseandisdispersedasdropletsinwater.Sometimes,butveryrarelyoilisproducedinadualemulsioninwhichthedispersedphaseisdropletsofoil-inwateremulsionandtheexternalphaseisoil.些油田偶尔会产生反相型乳状液,即油为相并呈油珠分散于水中。在极少数的情况下,原油以双重乳状液采出,分散相是水包油型乳状液,外相为油。Inwater-in-oilemulsion,therearetwoforcesindirectopposition.Oneforceisthefilmofemulsifyingagentthatsurroundsthewaterdroplets.Thisforcetendstopreventthedropletsfrommergingtogethertoformlargerdrops,evenwhenthedropletscollide.Theotherforceistheoppositetendencyofwaterdropletstojointogethertoformlargerdrops.Thelargerdropsyieldtotheforceofgravityandsettleout.Therefore.!obreakdownapetroleumemulsion,thepropertiesoftheemulsifyingagentmustbeneutralizedordestroyedsothatthedropletsofwatermayunite.Manyproceduresfortheneutralizationanddestructionoftheemulsifyingagenthavebeendeveloped.在油包水型乳状液存在两种起相反作用的力,一种力一与水珠周围的乳化剂薄膜有关,即使在水珠碰撞时,它也有阻止水珠合并而形成大水珠的趋势。另一种力是水珠有相互合并和形成大水珠的相反倾向。较大的水珠会在重力作用下沉降出来,因而要破坏石油乳状液,就必须抑制或破坏乳化剂的性质,使水珠合并。已经开发了许多抵消和破坏乳化剂的方法。1.3.2TheMajorReasonsforDehydratingCrudeOil1.3.2原油脱水的主要原因Theworldwidecrudeoilproductionofabout60millionbpdisaccompaniedbyatleastasmuchwater.Inoldfields,water-oilratiosgreaterthan10arenotuncommon.Therefore,itisnotasurprisethatemulsionformationistheruleratherthantheexception.Thesaltcontentoftheproducedbrinemayrangefrompracticallyzerotoalmostsaturated.Inparticular,dilutebrinesformemulsionswithcrudeoilthatcanbeverydifficulttobreak<i.e.,resolveintoseparateoilandwaterphases>.世界原油产量约为60×106bpd,伴随而产出的水量至少不低于原油产量。在老油田,水油比超过10者并不罕见。可见产生乳状液是正常现象,而非特例。产出盐水的盐含量围可能从零至几乎被盐饱和。由稀盐水和原油形成的乳状液很难破乳〔即很难分离为油、水两相。Themajorreasonsfordehydratinganddesaltingcrudeoilare:原油脱水脱盐的主要原因为：<1>Crudeoilpurchasersspecifymaximumpermissiblecontentsofsedimentsandwater,S&W,formerlycalledbasicsedimentandwater,BS&.W.Typically,limitsvaryfrom0.1—3wt.:0.1%incoldclimates,0.5%intheGulfcoastandTexas,and3%forlowgravityCaliforniacrude.〔1原油买方规定了最大允许沉积物和水的含量<S&W>,此含量以前被称为底部沉积物和水<BS&W>。典型的限定围为0.1%-3%<质量分数>,寒冷地区为0.1%,<墨西哥>海湾地区和得克萨斯州为0.5%,加利福尼亚州的低相对密度原油为3%。<2>Crudeoilisboughtandsoldona°APIgravitybasisandhigh-gravityoilscommandhigherprices.Waterlowersthe°APIgravityandreducesthesellingpriceofoil.〔2买卖原油以0API相对密度为基准,0API相对密度高的原油能得到较高的售价。原油的水降低了0API相对密度,因而降低了原油的售价。<3>Shippingemulsifiedoilwastescostlytransportationcapacitiesoccupiedbyvaluelesswater<i.e.,S&.W>.〔3由于无用的水占有体积,输送乳化原油浪费了宝贵的输送能力。<4>Theviscosityofcrudeoilincreasesasthewatercontentisincreased.<Adding1%morewater<orS&-W>typicallyproducesa2%viscosityincreaseina30°APIcrudeanda4%viscosityriseina15°APIcrude.>〔4随着水含量增加,原油猫度增大。0API相对密度为30的原油多增加1%的水,其黏度一般会增大2%;0API相对密度为15的原油的黏度约增大4%<5>Mineralsailspresentinoilfieldwaterscorrodeproductionequipment,tankcars,pipelinesandstoragetanks.〔5油田水存在矿物盐,会腐蚀生产设备、铁路油槽车、管道和储罐。<6>Refiningofwater-bearingcrudecancauseseverecorrosionandpluggingproblems.Distillationofcrudecontainingwater-borneinorganicsaltscontributestocorrosionandfoulingofrefiningequipment.UndersomecircumstanceschloridescanhydrolyzetoHC1,whichisextremelycorrosive.〔6炼制含水原油会引起严重的腐蚀和堵塞问题。蒸馏乳化水含无机盐类的原油将导致炼制设备的腐蚀和污垢。在某些环境下,氯化物会水解为盐酸,它的腐蚀性极强。1.3.3TreatingMethods1.3.3处理方法Anymethodofremovingwater,salt,sand,sedimentsandotherimpuritiesfromcrudeoiliscalledoiltreating.Oil-treatingmethodshaveonecommongoal,namely,toprovideasuitableenvironmentforgravitytoseparatethebrinefromthecrude.从原油脱除水、盐、砂、沉积物和其他杂质的任何方法都被称为原油处理。各种原油处理方法具有共性,即为重力沉降提供良好氛围,使盐水从原油分出。Thefollowingarecommontreatingmethods:以下为常用的处理方法:<1>Settlingorprovidinglowvelocity<reducedturbulenceandincreasedresidencetimetoallowfreewatertoseparate>.〔1沉降或提供较低流速〔减少湍流,并增加停留时间,允许分开游离水。<2>Degassingorseparatingthegasfromtheliquidasitisreleasedintheproductionequipment.Risinggasbubblesseverelyimpedethesettlingofwaterdrops.Manyreportshavedocumentedindetailthebenefitsofdegassingpriortoemulsiontreating.〔2当生产设备产生气体时,应使气体和液体分离<或称脱气>。上升的气泡会极力阻止水珠的沉降。许多报道详细证明了在处理乳状液前脱气的好处。<3>Chemicaltreatingoraddingemulsionbreakersordemulsifiers.〔3化学处理或添加破乳剂。<4>Washingorprovidingacontinuous-phasewaterwash.〔4水洗或提供连续相水洗。<5>Heatingtoreduceoilviscosityandaccelerateseparation.〔5加热以降低油粘度和并加速分离。<6>Electricaltreating<i.e.,applyingACand/orDCelectricfields>.〔6电处理〔即,使用交流和/或直流电场。<7>Mechanicaltreatingorprovidingincreasedsurfaceareatopromotedropcoalescence.〔7机械处理或增大水珠的表面积,以促进液滴聚结。Inaddition,fieldtreatingcanaccomplishmisteliminationandremovalofsand,sludge,andothersolids.Ofcourse,successfultreatingimpliesthatthecrudeoilmeetspipelineorrefiningspecifications—usually0.1%~1.0%S&W.Inaddition,thetreatedbrineorproducedwatermustbeessentiallyoil-freetosatisfyenvironmentaldischargeregulations<often15—40ppm>ortopreventreinjectionproblemssuchasscaleformationand/orreservoirplugging.Notethattheoil-in-waterenvironmentalregulationisfarmoreseverethanthewater-in-oiltransport/salesspecification.此外,现场处理能除去液雾、砂、淤泥和其他杂质。显然,对乳状液的成功处理可使原油满足管输或炼制的规—通常要求沉积物和水的质量分数为。0.1%-1.0%。另外,处理后的盐水或采出水必须基本上不含油以满足向环境排放的规定<常为15--40ppm>,或防止诸如生成水垢和/或堵塞油藏等采出水回注问题。注意:水包油乳状液的环境排放规定比油包水乳状液的管输/销售规严格得多。1.4OverviewofGas-handlingFacilities1.4气体处理设备概论Theobjectiveofagas-handlingfacilityistoseparatenaturalgas,condensate,oroilandwaterfromagas-producingwellandconditionthesefluidsforsalesordisposal.Thisvolumefocusesprimarilyonconditioningnaturalgasforsales.气体处理设备用于从气井井流中分离天然气、凝析液或油和水,并使这些流体符合销售或排放的要求。本节重点讨论如何使天然气的品质符合销售的要求。Fig.1-6isablockdiagramofaproductionfacilitythatisprimarilydesignedtohandlegaswells.Thewellflowstreammayrequireheatingpriortoinitialseparation.Sincemostgaswellsflowathighpressure,achokeisinstalledtocontroltheflow.Whentheflowstreamischoked,thegasexpandsanditstemperaturedecreases.Ifthetemperaturegetslowenough,hydrates<asolidcrystalline-like"ice",matter>willform.Thiscouldleadtoplugging,sothegasmayhavetobeheatedbeforeitcanbechokedtoseparatorpressure.Low-temperatureexchange<LTX>unitsandindirectfiredheatersarecommonlyusedtokeepthewellstreamfrompluggingwithhydrates.图1-6所示为用于处理气井气的生产设备方框图。在一级分离前井流可能需要加热。由于多数气井的压力很高,故用节流件来控制气体流量。气体节流时其体积膨胀,气体温度下降。如果节流后气体温度太低,将生成水合物<一种固态晶体状的似"冰"物质>。由于形成的水合物会引起堵塞,故气体节流至分离压力前可能需要加热。低温换热装置<LTX>和间接式加热炉常用于防止井流被水合物堵塞。Gastransmissioncompaniesrequirethatimpuritiesberemovedfromgasthepurchase.Theyrecognizetheneedforremovalfortheefficientoperationoftheirpipelinesandtheircustomersgas-burningequipment.Consequently,contractsforthesaleofgastotransmissioncompaniesalwayscontainprovisionsregardingthequalityofthegasthatis