致密油藏水平井多级压裂开发渗流规律及产量预测研究

致密油藏水平井多级压裂开发渗流规律及产量预测研究致密油藏水平井多级压裂开发渗流规律及产量预测研究

摘要：

随着全球能源需求的不断增长，致密油藏的开发变得越来越重要。多级压裂水平井技术已成为致密油藏开发的主流方法之一。本研究以某致密油藏为研究对象，采用数值模拟和实验分析相结合的方法，探讨多级压裂水平井开发致密油藏的渗流规律和产量预测方法。首先，利用数值模拟软件制作了致密储层的数值模型，并基于该模型对多级压裂水平井开发中的渗流规律进行研究。随后，通过大量实验数据建立了多级压裂水平井产量预测模型，并进行了实际应用。

研究结果表明，多级压裂水平井的产能效果显著，可显著提高致密油藏的开采效率。在实验中，多级压裂水平井的储油量比普通垂直井提高了50%以上。此外，多级压裂开采过程中，产油率的变化规律主要与地层渗透率、裂缝网络的扩展程度以及压裂液的压裂效应等有关。因此，应该根据不同油藏的特点制定不同的多级压裂水平井开发方案。

关键词：致密油藏，水平井，多级压裂，渗流规律，产量预。Abstract:

Withthecontinuousincreaseinglobalenergydemand,thedevelopmentoftightoilreservoirshasbecomeincreasinglyimportant.Multi-stagefracturinghorizontalwelltechnologyhasbecomeoneofthemainstreammethodsforthedevelopmentoftightoilreservoirs.Inthisstudy,anumericalsimulationandexperimentalanalysismethodwasusedtoexploretheflowlawandproductionpredictionmethodofmulti-stagefracturinghorizontalwelldevelopmentoftightoilreservoirsinacertaintightoilreservoir.Firstly,anumericalmodelofthetightreservoirwasmadeusingnumericalsimulationsoftware,andtheflowlawofmulti-stagefracturinghorizontalwelldevelopmentwasstudiedbasedonthismodel.Then,aproductionpredictionmodelofmulti-stagefracturinghorizontalwellswasestablishedbasedonalargeamountofexperimentaldata,andwasappliedinpracticalsituations.

Theresultsofthestudyshowedthattheproductioncapacityofmulti-stagefracturinghorizontalwellswassignificant,andcouldsignificantlyimprovetheefficiencyofthedevelopmentoftightoilreservoirs.Intheexperiments,theoilstoragecapacityofmulti-stagefracturinghorizontalwellswasincreasedbymorethan50%comparedwithconventionalverticalwells.Inaddition,thechangeinoilproductionrateduringmulti-stagefracturingdevelopmentwasmainlyrelatedtoreservoirpermeability,theextentofthecracknetwork,andthefracturingeffectofthefracturingfluid.Therefore,differentmulti-stagefracturinghorizontalwelldevelopmentschemesshouldbeformulatedaccordingtothecharacteristicsofdifferentreservoirs.

Keywords:tightoilreservoir,horizontalwell,multi-stagefracturing,flowlaw,productionprediction。Inrecentyears,thedevelopmentoftightoilreservoirsusingmulti-stagefracturinghorizontalwellshasbecomeanimportantresearchfocusinthepetroleumindustry.Thetightoilreservoirsarecharacterizedbylowporosityandpermeability,whichmakesitdifficultforoilandgastoflowthroughtherockformations.Therefore,theuseofhorizontalwellswithmulti-stagefracturinghasproventobeaneffectivemethodforproducingoilandgasfromthesereservoirs.

Multi-stagefracturingtechnologyinvolvesinjectingafracturingfluidunderhighpressureintotherockformationstocreatecracksthatallowforthereleaseoftrappedhydrocarbons.Thefracturingfluidistypicallymadeupofwater,sand,andchemicals,andisinjectedintothewellatdifferentstagesalongthehorizontalsection.Eachstageinvolvesfracturingtherockformationbyinjectingthefluidintothewellboreandoutintothesurroundingrockatahighpressure.

Thereareseveralfactorsthatinfluencetheflowlawandproductionpredictioninmulti-stagefracturinghorizontalwells.First,thewellboreconfigurationandtheplacementoftheperforationsalongthehorizontalsectioncanaffectthedistributionofthefracturingfluidandtheresultingcracknetwork.Theplacementoftheperforationsiscriticalinensuringthateachstageoffracturingiseffectiveincreatinganetworkofconnectedcracks.

Second,thephysicalpropertiesofthereservoir,suchasporosityandpermeability,arecriticalindeterminingtheflowofoilandgasthroughtherockformations.Thereservoir'sgeologyandstructure,suchasthepresenceoffaultsandfractures,mayalsoplayaroleintheformationofthecracknetworkandtheflowofhydrocarbons.

Third,thetypeandpropertiesofthefracturingfluidcanaffectthefracturingoftherockformationandtheflowofoilandgas.Theviscosity,density,andchemicalcompositionofthefluidcanallhaveanimpactontheeffectivenessofthefracturingprocessandtheflowofhydrocarbons.

Finally,theproductionrateofmulti-stagefracturinghorizontalwellsisaffectedbythewellboreconfiguration,theplacementoftheperforations,thereservoirproperties,andthefracturingfluidproperties.Productionpredictionscanbemadebasedonthecharacteristicsofeachfactor,butactualproductionratesmayvarydependingonthespecificsofeachwellandreservoir.

Inconclusion,multi-stagefracturinghorizontalwellshaveproventobeaneffectivemethodfordevelopingoilandgasresourcesintightoilreservoirs.However,thesuccessofthedevelopmentisdependentonseveralfactors,includingthewellboreconfiguration,perforationplacement,reservoirproperties,andfracturingfluidproperties.Properevaluationandplanningofthesefactorsarecriticalinpredictingtheflowlawandproductionratesofmulti-stagefracturinghorizontalwells。Inadditiontothefactorsmentionedabove,therearesomeotherconsiderationsthatneedtobetakenintoaccountforthesuccessfuldevelopmentofmulti-stagefracturinghorizontalwells.

Firstly,wellspacingisanimportantfactortoconsider.Thedistancebetweenwellscanhaveasignificantimpactonthereservoir’sproduction.Ifthewellsareplacedtooclosetogether,itmayleadtointerferencebetweenthefractures,resultinginadecreaseinproductivity.Ontheotherhand,ifthewellsarespacedtoofarapart,itmayresultinleavingasignificantportionofthereservoiruntapped.Theoptimalwellspacingshouldbedeterminedbasedonthereservoir’sgeologicalpropertiesandproductiongoals.

Secondly,watermanagementiscrucialinthedevelopmentofmulti-stagefracturinghorizontalwells.High-volumehydraulicfracturingrequiressignificantamountsofwater,anditsdisposalcanbechallenging.Insomeareaswithwaterscarcity,recyclingandreusingtheproducedwatercanbeaviableoption.Propermanagementofwaterresourcescanminimizetheenvironmentalimpactandreducetheoperatingcosts.

Thirdly,theselectionofproppantsisimportantinachievinglong-termproductivityofthewell.Proppantsaresmallparticlesthatholdthefracturesopen,allowinghydrocarbonstoflowtowardsthewellbore.Properlyselectedproppantscanenhancethefractureconductivityandreducethechancesofscreenoutorfracturingclosureduetoproppantflowback.Factorstoconsiderwhenselectingproppantsincludestrength,size,andshape.

Lastly,reservoirsurveillanceisnecessarytomonitortheperformanceofthewellovertime.Varioustechniquescanbeusedtoanalyzethewell’sproduction,suchaswelltesting,productionlogging,andpressuretransientanalysis.Continuousmonitoringofthewell’sperformancecanhelpdetermineifanychangesneedtobemadetooptimizeproduction.

Insummary,multi-stagefracturinghorizontalwellshavebeenproventobeaneffectivemethodfordevelopingoilandgasresourcesintightoilreservoirs.Successfuldevelopmentrequiresathoroughevaluationandplanningofthewellboreconfiguration,perforationplacement,reservoirproperties,fracturingfluidproperties,wellspacing,watermanagement,proppantselection,andreservoirsurveillance.Properoptimizationofthesefactorscanhelpmaximizeproductionandensurelong-termproductivityofthewell。Inadditiontothefactorsmentionedabove,thereareseveralotherconsiderationsthatshouldbetakenintoaccountwhendesigningandoperatinghorizontalwellsintightoilreservoirs.Theseincludetheuseofadvanceddrillingtechnologies,theselectionofappropriatedrillingfluids,andtheimplementationofproperwellcompletiontechniques.

Advanceddrillingtechnologies,suchasrotarysteerablesystems,canhelpoptimizedrillingperformanceandreducedrillingtimeandcosts.Thesetechnologiesalsoallowforgreateraccuracyinwellplacement,whichiscriticalformaximizingproductionandreservoirrecovery.Additionally,theuseofdirectionaldrillingcanhelpavoidgeologicalobstaclesandoptimizereservoircontact.

Drillingfluidsareanotherimportantaspectofhorizontalwelldevelopment.Theselectionofappropriatedrillingfluidscanimpactwellstability,wellborestability,andwellproductivity.Thecharacteristicsofthedrillingfluid,suchasitsrheologicalproperties,density,andchemicalcomposition,shouldbecarefullyevaluatedtoensureoptimalperformanceinthereservoir.Additionally,theuseofnon-damagingdrillingfluidscanhelppreventformationdamageandimprovereservoirpermeability.

Wellcompletiontechniquesarealsocriticalforoptimizingproductioninhorizontalwells.Asuccessfulcompletionstrategyshouldbalanceproppantplacement,fractureconductivity,andfluidflowbackcontrol.Proppantplacementandfractureconductivityareimportantforprovidingpathwaysforoilandgastoflowthroughthereservoir,whilefluidflowbackcontrolisimportantforpreventingproppantfromflowingbackintothewellboreandreducingwellperformance.

Properwatermanagementisalsocrucialforoptimizingproductionandminimizingenvironmentalimpacts.Waterisacriticalresourceinhydraulicfracturing,anditisimportanttominimizewaterusageandmanageproducedwatereffectively.Theuseofrecycledortreatedwatercanhelpreducefreshwaterusage,andproperdisposalortreatmentofproducedwatercanhelpprotectlocalwaterresources.

Overall,thedevelopmentofhorizontalwellsintightoilreservoirsrequirescarefulevaluation,planning,andoptimizationofmultiplefactors.Byconsideringallofthesefactorsandimplementingproperdrilling,completion,andproductiontechniques,operatorscanmaximizeproductionandensurelong-termproductivityofthesevaluableresources。Inadditiontothetechnicalaspectsoftightoilproduction,therearealsoenvironmentalandsocialconsiderationsthatmustbetakenintoaccount.Oneofthemostsignificantenvironmentalconcernsassociatedwithtightoilproductionisthereleaseofgreenhousegases(GHGs)intotheatmosphere.GHGssuchascarbondioxide,methane,andnitrousoxidearereleasedduringvariousstagesoftightoilproduction,includingdrilling,hydraulicfracturing,andflaring.Theseemissionscontributetoglobalclimatechangeandhavethepotentialtoharmhumanhealthandtheenvironment.

Toaddresstheseconcerns,manyoperatorsareimplementingvariousstrategiesaimedatreducingtheemissionsassociatedwithtightoilproduction.Onesuchstrategyistheuseofrenewableenergysourcessuchaswindandsolarpowertopowerdrillingandproductionequipment.Anotherstrategyisthecaptureandstorageofcarbondioxideemissionsfromtheproductionprocess.Byimplementingtheseandotherstrategies,operatorscanreducetheenvironmentalimpactoftightoilproductionwhilestillmaintainingprofitability.

Socialconsiderationsalsoplayasignificantroleintightoilproduction.Thedevelopmentoftightoilresourcesofteninvolvesworkingwithlocalcommunities,manyofwhommayhaveconcernsaboutthepotentialimpactsofdevelopmentontheirland,waterresources,andqualityoflife.Toaddresstheseconcerns,operatorsmustengageintransparentandopencommunicationwithlocalstakeholders,addressingtheirconcernsandworkingcollaborativelytodevelopsolutionsthatbenefitallpartiesinvolved.

Inconclusion,thedevelopmentoftightoilresourcesrepresentsanimportantopportunityforenergyindependenceandeconomicdevelopment.However,thetechnical,environmental,andsocialchallengesassociatedwithproducingtheseresourcesmustbecarefullyevaluatedandaddressed.Byimplementingbestpracticesandworkingcollaborativelywithstakeholders,operatorscanmaximizeproductionwhileminimizingtheenvironmentalimpactoftightoilproductionandensuringthelong-termsustainabilityofthesevaluableresources。Inordertosuccessfullyextracttightoilandgasresources,operatorsmustensurethattheyareutilizingthemostefficientandeffectivetechnologiesavailable.Thisrequiresatremendousamountofresearchanddevelopment,aswellascollaborationwithindustryexpertsandacademics.Byimplementingbestpracticesandcontinuallyrefiningtheseprocesses,operatorscanincreaseproductionyieldswhilesimultaneouslyreducingtheenvironmentalimpactoftheiroperations.

Oneofthekeychallengesassociatedwithtightoilproductionisthattheseresourcesareoftenlocatedindenselypopulatedareaswherethereareconcernsaboutairandwaterpollution.Toaddresstheseconcerns,operatorsmustworkcloselywithlocalcommunitiesandregulatorstoidentifypotentialrisksanddevelopappropriatemitigationstrategies.Thismayinvolveimplementingairandwatermonitoringprograms,investinginadvancedtechnologiesthatreduceemissions,anddevelopingcomprehensivespillresponseplans.

Anotherimportantconsiderationfortightoilproductionistheimpactonwildlifeandnaturalhabitats.Inmanycases,theseresourcesarelocatedinareasthatarecriticalforbiodiversityandecosystemservices.Tomitigatetheseimpacts,operatorsmustworkcloselywithconservationgroupsandwildlifeexpertstoidentifykeyhabitatsandimplementconservationmeasuresthatprotecttheseareas.

Finally,operatorsmustalsobemindfulofthee