氣藏工程翻譯版課件Chapter5 Pressure-Transient Testing of Gas Wells

氣藏工程翻譯版課件Chapter5Pressure-TransientTestingofGasWellsThestudyoffluidflowsofar流體流動(dòng)的研究到目前為止

:Knowingthereservoir(K,Φ)→calculateapressuredropforagivensetofconditions(givenq,flowregime).了解儲(chǔ)層（K，Φ）→計(jì)算對(duì)于給定的一組條件的壓降（給定的q，流型）。

Inreality,onlyflowratesandpressuresatwellscanbemeasureddirectly,andthemostimportantunknownfactoristhepermeability.在實(shí)際中,只有流量和壓力井可以直接測(cè)量,最重要的是滲透率是未知的Therefore,thepressuredropcanbecontinuouslymeasuredandthepermeabilitycalculated.因此，壓降可以連續(xù)測(cè)量和計(jì)算滲透率Thisispartoftheobjectivesofwelltesting.這是井測(cè)試的目標(biāo)的一部分5.1IntroductionPressure-transienttest壓力不穩(wěn)定試井:Atestinwhichwegenerateandmeasurepressurechangesinawellasafunctionoftime.一個(gè)測(cè)試中，我們產(chǎn)生和測(cè)量壓力變化與時(shí)間的一個(gè)函數(shù)。4HowisaWellTestConducted?qWellisallowedtoproducenormallySensorisloweredintowellPressuredrawdownorflowwelltest壓力降落試井5HowisaWellTestConducted?q=0tqtpSensorisloweredintowellWellisshutinProductiondropsto0PressurerisesPressurebuildupwelltest壓力恢復(fù)試井6WellTestObjectivesDeterminethenatureoftheformationfluids確定地層流體性質(zhì)Measurethewellproductivity測(cè)量油井的產(chǎn)能Measuretemperatureandpressure測(cè)量溫度和壓力Obtainsamplesforlabanalysis獲得實(shí)驗(yàn)室分析的樣品Obtaininformationforreservoirdescription(permeability,heterogeneity)獲得油藏描述信息(滲透率、非均質(zhì)性Estimatecompletionefficiency估計(jì)完成效率5.2TypeandPurposesofPressure-transienttests壓力不穩(wěn)定測(cè)井的類型和作用7PrincipalObjectivesofWellTesting試井的主要目標(biāo)

Determinetheaveragepermeabilityofthereservoir確定儲(chǔ)層平均滲透率Determinethenearwellborealteration,i.e.theskinfactor確定井筒附近表皮細(xì)數(shù)的變化Measurethereservoirpressure測(cè)量?jī)?chǔ)層壓力Attempttolocatethepositionofboundaries/discontinuities試圖找到/不連續(xù)邊界的位置8

Estimatetheinitialreservoirpressure,oraveragereservoirpressure估計(jì)初始儲(chǔ)層壓力,或平均儲(chǔ)層壓力Estimatetheflowcapacityoffluidinthereservoir估計(jì)在儲(chǔ)層流體的流量Determinetheeffectofstimulationmeasuresandtheextentofformationdamage確定的激勵(lì)措施，對(duì)油層污染程度的影響Estimatethegasinitiallyinplace估計(jì)地層儲(chǔ)量PrincipalObjectivesofWellTesting9TypesofPressure-transienttestSingle-welltest單井試井Multi-welltest多井試井Activewell-激動(dòng)井Observationwell-觀測(cè)井Single-welltestsmeasurepressurebuildup,drawdown,fall-offaswellasinjectivity單井試井壓力恢復(fù)、壓力降落、注入能力的下降Multi-welltestsincludeinterferencetestandpulsetest(干擾試井，壓力脈沖試井)10TypesofPressureTransientTestPressureDrawdownTest壓力降落試井PressureBuilduporFalloffTest壓力恢復(fù)或降落試井-DrillStemTest(中途測(cè)試)-ProductionorInjectionWellTest生產(chǎn)或注入井測(cè)試InterferenceTest干擾試井PulseTest-horizontalorvertical脈沖測(cè)井—水平和垂直11Pressureregimesinapetroleumreservoir一個(gè)油藏的壓力環(huán)境Steady-StateFlow穩(wěn)態(tài)流Semi-Steady-StateFlow12Pressureregimesinapetroleumreservoir地層徑向流邊界影響井筒或近井地層影響Diagramof3flowingstages135.3HomogeneousReservoirModel—SlightlyCompressibleLiquidsThebasisofwell-testanalysistechniquesforhomogeneous-actingreservoirsistheline-source(Ei-function)solutiontothediffusivityequation.對(duì)于均質(zhì)作用油藏試井分析技術(shù)的基礎(chǔ)是（EI函數(shù)）擴(kuò)散方程的線源解。FromChapter2,therelationshipbetweenbottomholeflowingpressure(BHFP),Pwf,andtheformationandwellcharacteristicsforawellproducingaslightlycompressibleliquidataconstantrateis:從第2章,一口微可壓縮流體的井以定產(chǎn)量生產(chǎn)井底流壓與構(gòu)造、特征參數(shù)的關(guān)系。Ifwechangefromnaturallogarithmstobase10logarithmsandsimplify,weget:如果我們從自然對(duì)數(shù)為基礎(chǔ)10對(duì)數(shù)和簡(jiǎn)化，我們得到145.3.1Analysisofconstant-rateflowtests<=>PressuredrawdowntestsVS.15Analysistechniqueforconstant-rateflowtestdata恒流量測(cè)試數(shù)據(jù)分析技術(shù)165.3.1Analysisofconstant-rateflowSettheflowtimet=1hour：5.3.2Analysisofpressure-builduptests17Potentialsuperpositionprinciple勢(shì)的疊加原理SuperpositionforShut-inBHP185.3.2Analysisofpressure-builduptestsy=mx+bVS.Graphicalanalysistechniqueforpressure-builduptestdata195.3.2Analysisofpressure-builduptestsWecanget:205.3.2Analysisofpressure-builduptests1.RadiusofInvestigation(探測(cè)/調(diào)查半徑)5.4ComplicationsinActualTests21IdealConditions:Homogeneous,infinite…ActualConditions:HeterogeneousConditionsinthewellboreanddrainageradiusofthereservoirDefinedasthepointintheformationbeyondwhichthepressuredrawdownisnegligible.定義為點(diǎn)的形成,一旦超過(guò),壓降可以忽略不計(jì)5.4ComplicationsinActualTests22Pressuredrawdowntests5.4ComplicationsinActualTests23Pressurebuilduptests2.TimeregionsontestplotsEarlytime:damagedorstimulatedzone.Wellborestorage.污染刺激區(qū)，井筒儲(chǔ)存Middletime:undamagedzone.Astraightline.未污染的區(qū)域。一條直線Latetime:reservoirboundary油藏邊界5.4ComplicationsinActualTests245.4ComplicationsinActualTestsInfluenceofdifferentboundarytypes253.Wellbore-storageeffects(井筒儲(chǔ)集效應(yīng))Wellboreunloading(井筒卸載):theinitialfluidproductionmeasuredatthesurfaceoriginatesfromfluidsstoredinthewellboreratherthanfromtheformation.Onlyafterwhatmaybeaprolongedtimedoesthebottomholeflowrateapproximatelyequalthesurfacerate.初始產(chǎn)出的流體是井筒內(nèi)儲(chǔ)存，只有經(jīng)過(guò)很長(zhǎng)時(shí)間井底流量約等于表觀速度265.4ComplicationsinActualTestsPressuredrawdowntests3.Wellbore-storageeffects(井筒儲(chǔ)集效應(yīng))Followingshut-inatthesurface,fluidcontinuestoflowfromthereservoirintothewellbore,compressingthegasandliquidalreadyinthewellboreandstoringmorefluid.Thiscontinuedproduction,whichalsoisaspecialtypeof.下列關(guān)于表面，流體流動(dòng)繼續(xù)從油藏進(jìn)入井筒，壓縮氣體和液體已經(jīng)在井筒和儲(chǔ)存更多的流體。這種持續(xù)的生產(chǎn)，這也是一種特殊類型的。275.4ComplicationsinActualTestsPressurebuilduptestsWellborestorageWellboreunloading井筒卸載Afterflow續(xù)流4.DamageandsimulationAnalysis285.4ComplicationsinActualTestsSkinFactorUniformpermeability,ksOuterradius,rsAdditionalpressuredrop,ΔPsDerivetheskinfactorofthenear-wellboredamageorstimulationeffectsforinfinitecylindricalreservoirwithline-sourcewell.推導(dǎo)出線源井的無(wú)限長(zhǎng)圓柱油藏近井眼污染或刺激對(duì)表皮系數(shù)的影響。4.DamageandsimulationAnalysis295.4ComplicationsinActualTestsSkinFactorDerivetheskinfactorofthenear-wellboredamageorstimulationeffectsforinfinitecylindricalreservoirwithline-sourcewell.Fromthesteady-stateradialflowequation:4.DamageandsimulationAnalysis305.4ComplicationsinActualTestsSkinFactorDerivetheskinfactorofthenear-wellboredamageorstimulationeffectsforinfinitecylindricalreservoirwithline-sourcewell.Skinfactor:Damageeffect污染效應(yīng):s>0Stimulationeffect刺激效應(yīng):s<0ObjectivesIdentifyrangeofvalidityofpressure,pseudopressure(視壓力),pressure-squared,,andadjustedpressure(修正壓力)analysismethods315.5FundamentalsofPressure-TransientTestingInGasWellsDiffusivityEquation-LiquidsContinuityEquation連續(xù)方程EquationofStateforSlightlyCompressibleLiquids微可壓縮液體狀態(tài)方程Darcy’sLaw達(dá)西定律linear325.5FundamentalsofPressure-TransientTestingInGasWellsRealGasLaw真實(shí)氣體定律

pV=znRTNomenclature:p-absolutepressure,psiV-volume,ft3z-realgascompressibilityfactor,dimensionlessn-numberofmolesR-idealgasconstant,10.72(ft3)(lb)/(mole)(in2)(R)T-temperature,R335.5FundamentalsofPressure-TransientTestingInGasWells1.RealGasPseudopressureandpseuodotime真實(shí)氣體的擬壓力和擬時(shí)間P——absolutepressure,psipp- realgaspseudopressure,psi2/cpp0- basepressure,psi.Arbitrary;oftentakentobe0oratmosphericpressurez- realgascompressibilityfactor,dimensionless- gasviscosity,cp345.5FundamentalsofPressure-TransientTestingInGasWells1.Normalizationofpseudopressureandpseuodotime正?；臄M壓力和擬時(shí)間355.5FundamentalsofPressure-TransientTestingInGasWellsReferencevaluesofpressureandtimeusedfornormalizationarearbitrary,suchasoriginalreservoirpressurepi,currentstaticdrainageareapressure,p.參考價(jià)值的壓力和時(shí)間用于規(guī)范化是任意的,如原始儲(chǔ)層壓力Pi,泄油區(qū)目前靜壓,p。AdjustedVariables校正系數(shù)Pseudopressureandpseudotimeprovideexcellentresultswhenusinganalysismethodsforslightlycompressibleliquidstoanalyzegaswelltests.However,theyareinconvenientfortworeasons.利用系統(tǒng)分析的方法對(duì)微可壓縮液體分析氣井測(cè)試擬壓力和擬時(shí)間提供優(yōu)異的結(jié)果然而，他們不方便的原因有兩個(gè)Theunitsofpseudopressureandpseudotimearesuchthatthenumericvaluesofthesevariableswilloftenbeintherangeof105to109.對(duì)擬壓力和擬時(shí)間單位，這些變量的數(shù)值往往會(huì)在105至109的范圍內(nèi)。.Theuseofpseudopressureandpseudotimerequiresseparatesetsofequationsforoilandgaswellsforeachtypeofanalysistobeperformed使用擬壓力和擬時(shí)間需要不同的方程對(duì)石油和天然氣井為每種類型的分析365.5FundamentalsofPressure-TransientTestingInGasWellsAdjustedVariablesAdjustedpressureandadjustedtimearedefinedbymultiplyingpseudopressureandpseudotimebyconstants.Thisgivesthenewvariablesthesameunits,andsimilarranges,aspressureandtime,respectively.校正壓力和校正時(shí)間的定義是擬壓力和擬時(shí)間乘以常數(shù)。這是分別為壓力和時(shí)間給新變量相同的單位，和類似的范圍內(nèi)。Theequationsforanalysisofgaswelltestsintermsofadjustedpressureandadjustedtimearequicklyobtainedfromthoseforanalysisofoilwelltestsbysimplesubstitutions.該方程對(duì)氣井測(cè)試分析，矯正時(shí)間和校正壓力可以通過(guò)簡(jiǎn)單的替換得到快于那些油井測(cè)試分析獲得。375.5FundamentalsofPressure-TransientTestingInGasWells1.Normalizationofpseudopressureandpseuodotime385.5FundamentalsofPressure-TransientTestingInGasWellsReferencevaluestimeusedfornormalizationaretakenatthestartofthereservoir:在油藏生產(chǎn)出去使用標(biāo)準(zhǔn)的參考時(shí)間值Foranewwell:AdjustedVariables校正變量Thei

initialreservoirpressure.Otherreferencepressures(suchascurrentaveragedrainageareapressure)mayalsobeused.i表示原始儲(chǔ)層壓力評(píng)估。其他參考?jí)毫?如當(dāng)前流域平均壓力)也可以使用。395.5FundamentalsofPressure-TransientTestingInGasWells2.PressureandTimeVariables405.5FundamentalsofPressure-TransientTestingInGasWellsForsomegasesathighpressure(e.g.above3000psia),anapproximationis在一些很高的壓力下的應(yīng)用Pressure:RangeofApplication應(yīng)用范圍Tf=200°FSG=0.6SG=0.8SG=1.0SG=1.2025002,0004,0006,0008,00010,000Pressure,psiap/m*z,psi/cp(x103)Fairlyconstantatrates>3,000psi415.5FundamentalsofPressure-TransientTestingInGasWells3.Pressure-squaredandTimeVariables425.5FundamentalsofPressure-TransientTestingInGasWellsForsomegasesatlowpressure(e.g.below2000psia),anapproximationis一些氣體在低壓力（如下面2000psia），是一個(gè)近似Pressure-SquaredRanges壓力平方的范圍

00.1602,0004,0006,0008,00010,000Pressure,psiamu*z,cpTf=200°FSG=1.2SG=1.0SG=0.8SG=0.6Fairlyconstantatrates<2,000psi435.5FundamentalsofPressure-TransientTestingInGasWellsGas-DependentVariablesPressure-Squared壓力平方-ValidOnlyforLowPressures僅適用于低壓力(<2000psi)Pressure-ValidOnlyforHighPressures(>3000psi)僅適用于高壓力RealGasPseudopressure-ValidForAllPressureRanges適用于所有的壓力范圍445.5FundamentalsofPressure-TransientTestingInGasWellsObjectivesEstimatepressuredropduetonon-Darcyflow估計(jì)由于非達(dá)西流的壓降A(chǔ)nalyzeflowandbuilduptestsusingsemiloganalysis使用半對(duì)數(shù)分析流量和恢復(fù)測(cè)試分析455.6Non-DarcyFlow5.6Non-DarcyFlow非達(dá)西流動(dòng)FlowequationsdevelopedsofarassumeDarcyflow流動(dòng)方程到目前為止認(rèn)為達(dá)西流Forgaswells,velocitynearwellboreishighenoughthatDarcy’slawfails氣井筒附近的，速度是足夠高的，達(dá)西定律不合適Non-Darcybehaviorcanoftenbemodeledasrate-dependentskinfactor非達(dá)西的表現(xiàn)通?？梢越楸砥ひ驍?shù)依賴率46ApparentSkinFactorThe“true”skinduetodamageorstimulationcannotbeobtainedfromasingleconstant-ratetest.真是的表皮受到污染和刺激不能從一個(gè)定產(chǎn)量單井測(cè)試中得到Nomenclature:s-“true”skinduetodamageorstimulation,dimensionlesss’-apparentoreffectiveskinfactorthatwouldbemeasuredduringfloworbuilduptest,dimensionlessD-non-Darcyflowcoefficient(assumedconstant),D/Mscfqg-gasflowrate,Mscf/D47EstimatingNon-DarcyCoefficient

FromMultipleTests024681002,0004,0006,0008,00010,000Flowrate,Mscf/DApparentskinfactors=3.4D=5.1x104D/Mscf48EstimatingNon-DarcyCoefficient

FromTurbulenceParameter估計(jì)非達(dá)西系數(shù)從湍流參數(shù)Often,onlyonetestisavailable通常，只有一個(gè)測(cè)試是可用的Ifso,wecanestimateDfrom如果是這樣的話，我們可以估算Dkg-effectivepermeabilitytogas,md- turbulenceparameter,ft-1g,wf-gasviscosityatflowingbottomholepressurepwf,cp49EstimatingTurbulenceParameter估計(jì)湍流參數(shù)Ifisnotknown,itcanbeestimatedfrom50Gaswellsareproducedatconditionsapproximatingconstantwell-headpressureorvariablebottomholerates,ratherthanatconstantbottomholerates,inmostgasfieldoperations.在大多數(shù)氣田操作氣井生產(chǎn)條件近似恒定井底壓力或可變的流速,而不是在恒定井底流速。

Inaddition,manygas-welltests,especiallydeliverabilitytests,areconductedundervariable-rateconditions.此外，許多氣井產(chǎn)能測(cè)試試驗(yàn)，特別是，變產(chǎn)量條件下進(jìn)行的。Weconcentrateonanalysistechniquesforvariablegasrates,includinggas-welltestswithdiscretechangesandtestsinwhichtheratesaresmoothlychanging.我們致力于為可變氣率分析技術(shù)，包括氣井測(cè)試與離散的變化和測(cè)試中，利率平滑變化。5.7AnalysisofGas-WellFlowTests511.Constant-RateGasFlowTests定產(chǎn)量氣體流動(dòng)測(cè)試5.7AnalysisofGas-WellFlowTests522.GasFlowTestswithDiscreteRateChanges離散率的變化，氣體流量測(cè)試5.7AnalysisofGas-WellFlowTestsTomodelavariable-rategasflowtestusingsuperpositionintime53542.GasFlowTestswithDiscreteRateChanges，氣體流量測(cè)試離散率的變化5.7AnalysisofGas-WellFlowTests552.GasFlowTestswithDiscreteRateChanges5.7AnalysisofGas-WellFlowTests562.GasFlowTestswithDiscreteRateChanges–Example15.7AnalysisofGas-WellFlowTestsForaninfinitereservoir,datadescribingthewellandformationsaresummarizedbelow.Tocalculatethedown-holepressureafterproducts20h.對(duì)于一個(gè)無(wú)限的油藏，井和地層數(shù)據(jù)描述如下。計(jì)算井底壓力20h后的產(chǎn)量rw=0.5ft,μ=0.72cp,k=0.1md,Φ=0.23,re=+∞ft,Bo=1.475RB/STB,pi=3000psia,h=100ft,ct=1.5×10-5psi-1,s=0572.GasFlowTestswithDiscreteRateChanges–Example15.7AnalysisofGas-WellFlowTests582.GasFlowTestswithDiscreteRateChanges–Example15.7AnalysisofGas-WellFlowTests592.GasFlowTestswithDiscreteRateChanges–Example25.7AnalysisofGas-WellFlowTestsForagaswelltestedwithdiscreteratechanges.Assumingthatnon-Darcyeffectsarenegligible,estimatetheaveragegaspermeabilityandskinfactorusingthefollowingparameters:對(duì)于氣井測(cè)試與離散率的變化。假設(shè)非達(dá)西效應(yīng)可以忽略不計(jì)，估計(jì)平均氣體滲透率和表皮因子使用以下參數(shù)：t(hours)Pwf(psia)Pa,wf(psia)q(Mscf/D)061804709.40656666.427118832142.226079.51130258.9250412.51646535.223095.7.3Variable-RateGasFlowTestsWithSmoothlyChangingRates可變速率氣體流量測(cè)試與平滑變化率Inmanytestingsituations,astrictlyconstantproducingrateisimpracticalorimpossibletomaintain.在許多測(cè)試的情況下，嚴(yán)格的生產(chǎn)速率常數(shù)是不切實(shí)際或不可能維持Amoreprobablemodeofoperationisproductionataconstantsurfacepressure,andiftubingfrictioneffectsarenegligible,theBHPalsoisconstant.一個(gè)可能的操作方式是在一個(gè)恒定的表面壓力的生產(chǎn)，如果管摩擦的影響可以忽略不計(jì)，井底流壓也不變Atearlytimes,however,bothBHPandbottomholeratemaybechangingrapidly.在早期，井底流壓與井底流速可能迅速改變Dataobtainedunderthesenonidealtestconditionscanbeanalyzedaccuratelywithasimplemodificationofthetransientflowequationforconstant-rateproduction.這些非理想的測(cè)試條件下獲得的數(shù)據(jù)可以用于定產(chǎn)量的不穩(wěn)定流動(dòng)方程的一個(gè)簡(jiǎn)單的修改，準(zhǔn)確的分析。60Forslightlycompressibleliquids,Toanalyzevariable-ratetestsingaswellsinwhichnon-Darcyeffectsareimportant,wecanrewritetheaboveequationintermsofadjustedpressures分析變化率率在氣井測(cè)試非達(dá)西效應(yīng)是重要的,我們可以重寫上述方程的調(diào)整壓力:whereNon-Darcyflowcoefficient61Oncewehaveidentifiedthesemilogstraightlineindicativeofthemiddle-timeregion,kisestimatedfromthem’ofthisline:一旦我們確定了半對(duì)數(shù)直線表示中間的時(shí)間區(qū)域，K是從這條線的M估計(jì)andmustlieonthesemilogstraightlineoritsextrapolationto1hour.where62Typecurves:plotsoftheoreticalsolutionstoflowequations,presentedindimensionlessvariables.理論解決流動(dòng)方程圖，

提出了無(wú)量綱變量Identifytheappropriatereservoirmodel確定合適的油藏模型Identifytheappropriateflowregimesforanalysis分析適當(dāng)?shù)牧餍妥R(shí)別Estimatereservoirproperties估算儲(chǔ)集性能Developmentoftypecurves標(biāo)準(zhǔn)曲線的趨勢(shì)Gas-welltestanalysisusingtypecurves使用標(biāo)準(zhǔn)曲線分析氣井試井Gas-welltestanalysiswithderiv