Abstract: In recent years, with the growth of oil consumption and the reduce of new proved reserves, the development of high viscosity oil reservoir was paid more and more attention. As Kongnan block of Dagang oilfield has characteristics of hypercoagulability, high viscosity and high salinity, core flow experimental apparatus and core displacement experiment apparatus were used to study the effect of oil displacement efficiency of polymer/surfactant combination system, and analyze the mechanism of the relationship between recovery growth and core permeability. The results showed that, for the weak heterogeneous reservoir, with the increase of core permeability, the resistance coefficient and residual resistance coefficient of the polymer/surfactant combination system were decreased. With the increase of viscosity ratio (μsp/μo) and core permeability, the oil recovery increased, but the increase rate decreased. With the increasing of the core permeability, the size of the rock increased, while the inaccessible pore volume decreased. So the adaptability of the reservoir and the polymer/surfactant combination system was affected by the average permeability, and then the effect of the polymer flooding of the polymer/surfactant combination system flooding was influenced. Comprehensively considering technical and economic effects，the reasonable viscosity ratio (μsp/μo) in polymer flooding should be about 0.5~1.0．

Key words: Hypercoagulable and high viscosity reservoir and high salt, Polymer/surfactant combination system, Homogeneous core, Oil displacement efficiency, Influencing factors, Physical simulation

摘要： 针对大港油田孔南地区高凝高黏高盐油藏的特点,采用岩心流动实验装置和岩心驱油实验装置,开展了聚合物/表面活性剂二元复合体系驱油效率及其影响因素的研究,分析了聚/表二元复合驱采收率增幅与岩心渗透率之间关系机理。结果表明,对于非均质性较弱储层,随岩心渗透率增加,聚/表二元体系阻力系数和残余阻力系数减小。随聚/表二元体系与原油黏度比(μsp/μo)和岩心渗透率增大,采收率增幅增加,但增幅增加速度减小。随储层平均渗透率增加,岩石吼道尺寸增大,不可及体积减小。因此,储层平均渗透率大小会影响聚/表二元复合体系储层适应性,进而影响聚/表二元复合驱增油效果。从技术和经济角度考虑,目标油藏均质储层聚/表二元复合驱合理黏度比(μsp/μo)范围在0.5~1.0。

关键词: 高凝高黏高盐油藏, 聚/表二元体系, 均质岩心, 驱油效率, 影响因素, 物理模拟