普通稠油非均相复合体系组分驱油贡献率

Components Contribution in Heterogeneous Compound System during the Flooding Process of Conventional Heavy Oil

非均相复合体系能实现协同调驱,在稠油开发方面极具潜力,但各组分驱油贡献率不明确,给体系优化与选择带来盲目性。针对由部分水解聚丙烯酰胺、双效型表面活性剂和预交联凝胶颗粒(B-PPG)组成的非均相复合体系,在分析其界面与封堵性能和驱油特征的基础上,开展了聚合物、二元复合体系和非均相复合体系驱油实验;依据3类体系驱油的采收率增幅,归一化计算了不同水油黏度比下非均相复合体系组分驱油贡献率。结果表明,0.106~0.150 mm(150~100目)B-PPG膨胀后的粒径中值为800μm。该非均相复合体系与渗透率为1.1μm~2的填砂模型匹配,运移封堵阻力系数与残余阻力系数分别为420.5和203.0,更低渗透率(0.30μm~2)的填砂模型则难以进入。对于渗透率级差约为3.0的并联填砂模型,非均相复合体系具有较强的调驱能力,最高注入压力为0.42 MPa、低渗透模型分流率最高达到42.2%;而二元复合体系的最高注入压力仅为0.25 MPa、低渗透模型分流率仅为24.3%。当水油黏度比为0.05~0.46时,非均相复合体系中聚合物驱油贡献率(43.1%~84.1%)最高,表面活性剂(22.1%~7.6%)最低,B-PPG(34.8%~8.3%)介于两者之间。水油黏度比(≥0.46)较高时,表面活性剂和B-PPG驱油贡献率较小,聚合物或二元复合驱后非均相复合驱增油潜力有限;水油黏度比(≤0.2)较低时,表面活性剂和B-PPG驱油贡献率大,水驱或聚合物、二元复合驱后非均相复合驱增油潜力较大。

The heterogeneous compound system can realize coordination of profile regulation and oil displacement,which has great potential in heavy oil recovery.However,the contribution of its components to oil flooding is not clear,which brings blindness to the optimization and selection of oil flooding system.For a heterogeneous compound system,consisting of partially hydrolyzed polyacrylamide,dual-effect surfactant and branched performed particles gel(B-PPG),based on the analysis of its interfacial,plugging properties and oil flooding characteristics,flooding experiments of polymer,compound system and heterogeneous compound system were carried out.According to the oil recovery increments obtained by those three types of systems,the contribution of components in heterogeneous compound system on oil displacement under different water-oil viscosity ratios was calculated by normalization.The results showed that a B-PPG sample with initial size of 0.106—0.150 mm(150—100 mesh)behaved a median particle size of 800μm after expansion.The corresponding heterogeneous compound system matched with a sand pack with a permeability of 1.1μm2,where its measured resistance and residual resistance factor was 420.5 and 203.0.When a sand pack with lower permeability of 0.3μm2 was encountered,it could not be injected.For a parallel sand pack with a permeability contrast of about 3.0,heterogeneous compound system performed strong profile-control capacity.The maximum injection pressure was 0.42 MPa,and then the maximum fractional flow in low permeability model was 42.2%.While those of the single compound system were only 0.25 MPa and 24.3%,respectively.Under water-oil viscosity ratios of 0.05—0.46,the polymer component made the highest contribution to oil recovery of 43.1%—84.1%in heterogeneous compound system,the surfactant did the lowest of 22.1%—7.6%,while the B-PPG was intermediate of 34.8%—8.3%.At high water-oil viscosity ratios(≥0.46),the contribution of surfactant and B-PPG was small,and the oil recovery potential of heterogeneous compound system after polymer or compound flooding was limited.When the water-oil viscosity ratio(≤0.2)was low,the contribution of surfactant and B-PPG particles got large,and the oil recovery potential of heterogeneous compound system after both water and polymer/compound flooding was great.