Enhanced Oil Recovery Using Micron-Size Polyacrylamide Elastic Microspheres: Underlying Mechanisms and Displacement Experiments
Enhanced Oil Recovery Using Micron-Size Polyacrylamide Elastic Microspheres: Underlying Mechanisms and Displacement Experiments
复制标题
DOI：
10.1021/acs.iecr.5b02717
复制
发表时间：
2015-11-04
影响因子：
4.2
通讯作者：
Steenhuis, Tammo S.
中科院分区：
文献类型：
--
作者：
Yao, Chuanjin;Lei, Guanglun;Steenhuis, Tammo S.
微米级聚丙烯酰胺弹性微球(MPEM)是一种新型调驱非均质油藏调驱剂。在本研究中，通过实验室实验来表征MPEM在盐水中的粘弹性。采用透明充砂微观模型研究微观渗流和驱替机理，采用平行充砂模型研究MPEM在非均质油藏中的调驱效果。结果表明，MPEM几乎不会增加注入水的粘度，可以方便地利用原有注水管线进行注水。MPEM在多孔介质中的微观调驱机理主要表现为对大孔道的选择性封堵、MPEM封堵后的流体转移、MPEM突破导致的排油和油滴汇聚成油的机理。MPEM具有很高的封堵强度，可以承受长期的水洗。MPEM可以选择性地进入和堵塞高渗透砂岩中的大孔隙和孔喉，但几乎不会对低渗透砂岩造成损害。MPEM能有效地将高渗透砂层的水流分流到低渗透砂层，提高低渗透砂层和高渗透砂层中低渗透区的波及效率。研究结果也证实了MPEM在非均质油藏调驱的动态过程。
Micron-size polyacrylamide elastic microsphere (MPEM) is a newly developed profile control and oil displacement agent for enhanced oil recovery in heterogeneous reservoirs. In this study, laboratory experiments were performed to characterize the viscoelastic properties of MPEMs in brine water. A transparent sandpack micromodel was used to observe the microscopic flow and displacement mechanisms, and parallel-sandpack models were used to investigate the profile control and oil displacement performance using MPEMs in heterogeneous reservoirs. The results indicate that MPEMs almost do not increase the viscosity of injection water and can be conveniently injected using the original water injection pipelines. The microscopic profile control and oil displacement mechanisms of MPEMs in porous media mainly behave as selective-plugging in large pores, fluid diversion after MPEMs plugging, oil drainage caused by MPEMs breakthrough, and the mechanism of oil droplets converging into oil flow. MPEMs have a high plugging strength, which can tolerate a long-term water flushing. MPEMs can selectively enter and plug the large pores and pore-throats in high-permeability sandpack, but almost do not damage the low-permeability sandpack. MPEMs can effectively divert the water flow from the high-permeability sandpack to the low-permeability sandpack and improve the sweep efficiency of low-permeability sandpack and low-permeability area in the high-permeability sandpack. The results also confirm the dynamic process of profile control and oil displacement using MPEMs in heterogeneous reservoirs.