稠油减氧空气泡沫驱注入参数优化及现场应用

Injection Parameter Optimization of Deoxidized Air Foam Flooding for Heavy Oil Reservoir and Its Field Application

针对鲁克沁稠油油藏泡沫驱开采存在的气锁、注入参数不合理等问题,通过物理模拟实验,对减氧空气泡沫驱注入参数进行了优化。研究表明:水驱突破时开展减氧空气泡沫驱,采出程度增幅最高,含水率明显下降;采用气液交替注入方式替代气液同注方式,可避免井筒内气液分离和腐蚀问题,且当减氧空气和发泡液的单次注入量为0.1倍孔隙体积时,驱替效果与气液同注效果相当。室内获得的最佳注入参数为:水驱含水率达70%时转泡沫驱,液和气交替注入,单次注入0.1倍孔隙体积,注入速率为0.3 mL/min。现场施工参数调整后,试验区日增油为42 t/d,含水率下降28个百分点,累计增油为1.4×10^4t,产水量降低2.65×10^4m^3。现场试验证明,减氧空气泡沫驱优化方案切实可行,该成果为鲁克沁稠油规模开发提供了重要技术支持。

In order to improve the gas lock,unreasonable injection parameters and other problems in the foam flooding of Lukeqin heavy oil reservoir,the deoxidized air foam flooding injection parameters were optimized by laboratory physical simulation experiment.Research indicates that a maximum recovery degree increment and a significant water cut increase can be realized by immediately carrying out deoxidized air foam flooding after water breakthrough.Alternate gas-liquid injection pattern is recommended rather than gas-liquid coinjection pattern to avoid gas-liquid separation and corrosion in wellbore.A comparable displacement performance to gas-liquid coinjection can be obtained when the single injection volumes of deoxidized air and foam liquid are 0.1 time pore volume.The optimal parameters according to the laboratory test include foam flooding implementation when the water cut is 70%,alternate liquid-gas injection,0.1 time PV injection in a single treatment.After field parameter adjustment,the daily oil increment of test zone is 42 t/d,the water cut is reduced by 28 percentage points,the cumulative oil increment is 1.4×10^4t,and the water production is reduced by 2.65×10^4m^3.Field test shows a favorable feasibility for the deoxidized air foam flooding program,which could provide certain technical reference for the large-scale development of Lukeqin heavy oil reservoir.