【7A文】Factors Affecting Water Injectivity—Waterflood Enhanced Recovery.ppt

《【7A文】Factors Affecting Water Injectivity—Waterflood Enhanced Recovery.ppt》由会员上传分享，免费在线阅读，更多相关内容在工程资料-天天文库。

1、FactorsAffectingWaterInjectivity——waterfloodenhancedrecoverysummaryBackgroundKey/SolutionProblem/Consideration——Waterfloodinghasalengthyhistoryofapplicationinthepetroleumindustry.——Injectivitydecline——Theinjectionratesummarysummarypurposeofwaterflooding:restoretheformationpressureImprov

2、etheefficiencyoffloodingStabilizethecapacityofproductionwellsummarytubinginjectionannuluswaterinjectioncommingledwaterinjectionseparatedlayerwaterfloodingseveralmethodsofwaterflooding:summaryFactorsAffectingWaterInjectivitySandProductionScalesSuspendedSolidsFluidCompatibilityWaxPrecipit

3、ationThermalStressEffectsColdWaterInjectionSandProductionInpoorlyconsolidatedreservoirs,sandfailureproblemsmaycausesevereoperationaldifficulties.ScalesScaleformationisafamiliarproblemforoilfieldengineersanditisoftencausedbythemixingoftwoormorebrines.scalesthatblockupthepipeSuspendedSoli

4、dsThewaterquality,usuallymeasuredbyitscontentofsuspendedsolids,hasbeenanimportantcriterioninthedesignofacosteffectivewaterfloodingprojectregardlessofseawaterinjectionorproducedwaterre-injection.WaxPrecipitationThetemperaturearoundwaterinjectors,maydropbelowcrudeoil’scloudpointbecauseofc

5、oldwaterinjection,whichleadstowaxprecipitation.Waxprecipitationwillimpairinjectivity.FluidCompatibilityInsomewaterfloodingprojects,freshwaterneedstobeinjectedintosubsurfaceformationswhensuitablebrinewaterisnotavailableortoocostly.Inthiscase,ifthereservoirrockscontaininterstitialclaywhic

6、hswellsanddispersesintheinjectedfreshwater,thewellinjectivitywilldeclinebecauseofpermeabilityimpairment.ThermalStressEffectsWhencoldwaterisinjectedintosubsurfacereservoirs,thereservoirrockwillbecooledbyinjectedcoldwater,whichcancausethenearwellborerocktoshrinkawayfromhotsurroundingrocks

7、.Therefore,theinjectionofcoldwatercaninducethermalstressesinthenearwellboreregionandcreatenewfractures.ColdWaterInjectionTheformingofacoldwaterbankaroundaninjectorcanimpairinjectionperformanceduetotheimpactoftemperatureonwaterviscosityanditwouldalsoleadtoahigherskin.ConclusionT