Abstract

A new gel particle named pore-scale polymer microspheres (PMs) has been considered as an effective chemical enhanced oil recovery (EOR) agent used for conformance control. But how to achieve deep profile control of PMs remains some problems. This work aimed at investigating the effect of PMs on oil-water relative permeability and oil-in-water emulsion stability. The results indicated that as PMs diameter matched well with pore-throats size, the PMs could exhibit a superior dynamic migration and plugging performance in the core; in this scenario, in the course of PMs flooding and subsequent water flooding, water phase permeability fluctuated obviously, and oil phase permeability increased and then decreased. Additionally, it was observed that the PMs could reduce the negative influence of elevated mobility ratio caused by the increment in oil viscosity to promote oil seepage. The zeta potential results indicated that the PMs facilitated enhancing oil-in-water emulsion stability, predominantly as a result of the increase of electrostatic repulsion between oil droplets, and deceleration of floating and convergence of oil droplets.

摘要

一种名为孔隙尺度聚合物微球 (PMs) 的新型凝胶颗粒被认为是一种有效的化学提高采收率 (EOR) 剂，用于一致性控制。但如何实现永磁体的深度调剖仍存在一些问题。这项工作旨在研究 PMs 对油水相对渗透率和水包油乳液稳定性的影响。结果表明，由于颗粒物直径与孔喉尺寸匹配良好，颗粒物在岩心中表现出优异的动态运移和封堵性能；该情景下，在PMs驱和后续水驱过程中，水相渗透率波动明显，油相渗透率先增后减。此外，观察到，PMs 可以减少由油粘度增加引起的流动比升高的负面影响，以促进油渗。zeta 电位结果表明，PMs 有助于增强水包油乳液的稳定性，主要是由于油滴之间的静电排斥力增加，以及油滴的漂浮和收敛速度减慢。