三塘湖油田微泡沫防漏钻井液技术研究与应用

为减少低压地层的井漏问题,室内将优选出的高效起泡剂与稳泡剂、抑制剂、降失水剂、井壁稳定剂等进行配伍,形成了微泡沫钻井液。在微观结构研究中,微泡沫显示了独特的多层膜结构特征,膜强度高,微泡沫在钻井液中分布均匀,可以有效降低钻井液的密度。室内对微泡沫钻井液性能的研究表明,微泡沫钻井液密度低,可以适应高温高压的地层条件,抑制性强,可较大幅度地提高油气层保护效果。在三塘湖油田的应用表明,微泡沫钻井液适用于封堵低压漏失地层,且现场配制简单、易于转化、维护方便,钻井液性能稳定,能够满足钻井工艺的要求,泥浆泵上水正常,应用井段钻井液密度降低到0.95g/cm~3以下,防止了井漏情况发生,减轻了油气层污染,保证了钻井工作的顺利进行。

Researchandapplicationofleakprevetionmicro-foamdrillingfluidinSantanghuoilfield

Tosolvetheproblemofwellleakageinlowpressurereserve,acirculativemicro-foam drillingfluidwasdevelopedbycombininghigheffectivefoamagentwithfoamstabilizer,inhibitor, filtratereducerandboreholestabilizer.Theuniquemultilayerfilmstructureofmicro-foamismadeup ofonenucleusandtwolayersandthreelayersfilm,andthemicro-foamhasahighfilmstrengthand canbeuniformlydispersedindrillingfluid,whichcanefficientlyreducethedensityofdrillingfluid. Theperformanceevaluationindoorsshowsthatthedensityofdrillingfluidislow,anditisfitfor HTHPformation,therejectioncapabilityofdrillingfluidisstrong,whichcaneffectivelyenhance reserveprotectioneffect.TheapplicationsinSantanghuoilfielddemonstratethatthe micro-foam drillingfluidissuitableforpluggingthelow-pressurecirculation-lostzones.Thedrillingfluidiseasy toprepare,transformandmaintaininfieldapplication.Thepropertyofdrillingfluidisstable,which canmeettherequirementofdrillingprocess,andthemudpumpworksasnormal.Thedrillingfluid densityislessthan0.95g/cm3,whichpreventsthewellleakageandreducesthereservepollution.It isapprovedthatthemicro-foamdrillingfluidishelpfulfordrillingsafetyandquality.