聚合物与预交联凝胶颗粒复合调驱室内评价

Laboratory evaluation of polymer and pre-crosslinking gel particle compound flooding

敖文君 康晓东 黄波 王姗姗 李先杰 梁丹 3

中海油能源发展股份有限公司工程技术分公司，天津 300452 中海油海洋石油高效开发国家重点实验室，北京 100028 中海油研究总院有限责任公司，北京 100028

CNOOC EnerTech-Drilling & Production Co., Tianjin 300452, China State Key Laboratory of Offshore Oil Exploitation, Beijing 100028, China CNOOC Research Institute, Beijing 100028, China

海上非均质油藏经长期注聚开发后，非均质性增强，出现注水突进严重、含水率高等问题，针对这一问题，通过室内体系评价、物理模拟及理论分析方法，研究了聚合物与预交联凝胶颗粒（PPG）复合调驱体系的黏弹性能、封堵性能及调剖能力。结果表明：所形成的复合体系同时具有较好的黏性性能与弹性性能；在聚合物驱注入实验过程中，压力与阻力系数具有快速上升与快速下降的规律；PPG在注入过程中注入压力曲线呈现较大的“凸”形，在岩心中运移过程的形式是“运移—封堵—突破—运移”，而复合体系则具备了聚合物和PPG两者的优势特性，对非均质储层，可实现深部运移与封堵。从驱油效果可以看出，相比单一注聚合物、PPG体系，复合驱过程中含水率下降漏斗面积较大，最终采收率为54.8%，提高采收率分别为3.6，7.7百分点。所形成的复合调驱体系能较好地解决目前海上非均质注聚油藏出现的注水突进严重、含水率过高等问题。

After long term polymer flooding, the heterogeneity of offshore heterogeneous reservoir has been enhanced, resulting in serious water injection breakthrough and high water cut. In view of these problems, the viscoelasticity, plugging performance and profile control ability of polymer and pre-crosslinking gel particle(PPG) compound flooding system were studied through indoor system evaluation, physical simulation and theoretical analysis. The results show that the compound system has both good viscosity and good elastic property. It is found that the pressure and resistance coefficient increase and decrease rapidly during the experiment of polymer flooding injection. In the process of PPG injection, the injection pressure curve presents a large "convex" shape, and the PPG migration in the core is in the form of "migration-plugging-breakthrough-migration". However, the compound system has the advantages of polymer and PPG, and can be used for deep migration and plugging of heterogeneous reservoir. The oil displacement effect shows that, compared with the single polymer flooding and the PPG flooding, the area of water cut decrease funnel is larger in the process of compound flooding. The final recovery rate of the compound flooding is 54.8%, which is increased by 3.6% and 7.7% respectively compared with the single polymer flooding and the PPG flooding. The compound system can better solve the problems of serious water injection breakthrough and high water cut in offshore heterogeneous reservoirs at present.

10.6056/dkyqt202103024