Abstract: Fault block M belongs to heavy oil reservoir with thick layer. How to further tap potential and improve oil recovery after entering polymer flooding development is particularly important. In the past, the influence of sweep volume and displacement efficiency on oil recovery has been the main concern in the theoretical study of enhanced oil recovery, while the contribution of sweep volume and displacement efficiency to enhanced oil recovery has been less studied. The characteristics of oil displacement efficiency and sweep volume in the polymer flooding process of M fault block were studied using the method of reservoir engineering which adopted the experimental method of indoor physical simulation, based on the relationship between resistance and oil saturation. And the contribution generated from oil displacement efficiency and sweep volume to enhance oil recovery was discussed. The results showed that the main contribution of polymer flooding was to enlarge the sweep volume of each layer. The contribution generated from the medium permeability layer to enhance oil recovery was 61.79%. And secondly, the contribution generated from high and extra⁃high permeability layer was 34.48%, while the low permeability layer was only 3.73%.

Key words: Heavy oil, Polymer flood, Volumetric sweep efficiency, Displacement efficiency

摘要： M断块属于稠油厚油层油藏，进入聚合物驱开发后如何进一步挖潜和提高采收率尤为重要。过去在提高采收率理论研究过程中主要关注的是波及体积和驱油效率对采收率的影响，对于波及体积和驱油效率对提高采收率的贡献研究较少。现有方法确定的驱油效率和波及系数存在精确度低的缺陷，且计算可靠性和准确性也无法得到验证。采用室内物理模拟实验手段，以电阻-含油饱和度关系曲线为研究基础，研究了M断块聚合物驱油过程中不同层位及不同位置驱油效率与波及体积的变化特征，探讨了聚合物驱驱油效率与波及体积对提高采收率的贡献值。结果表明，聚驱主要贡献为扩大各层波及体积，中渗层对于采收率贡献达到61.79%，其次是高渗及特高渗透层，贡献率为34.48%，而低渗层仅为3.73%。

关键词: 稠油, 聚合物驱, 驱油效率, 波及系数