智能水驱基于界面离子调控机制的提高采收率机理研究  

Investigation into the oil recovery mechanism in smart waterflooding:Based on the ionic regulation of the interfaces

作　　者：王晓 吴晓亮 施雷庭[1,2] 刘静静 叶仲斌[1,3] 刘万发 秦国伟 WANG Xiao;WU Xiao-liang;SHI Lei-ting;LIU Jing-jing;YE Zhong-bin;LIU Wan-fa;QIN Guo-wei(State Key Laboratory of Oil&Gas Reservoir and Exploitation Engineering,Southwest Petroleum University,Chengdu 610500,China;College of Oil and Natural Gas Engineering,Southwest Petroleum University,Chengdu 610500,China;Chengdu Technological University,Chengdu 611730,China;College of Petroleum Engineering,Xi’an Shiyou University,Xi’an 710065,China)

机构地区：[1]西南石油大学油气藏地质及开发工程国家重点实验室,四川成都610500 [2]西南石油大学石油与天然气工程学院,四川成都610500 [3]成都工业学院,四川成都611730 [4]西安石油大学石油工程学院,陕西西安710065

出　　处：《应用化工》2023年第7期1962-1967,1973,共7页Applied Chemical Industry

基　　金：国家自然科学基金青年基金项目(52104040);油气藏地质及开发工程国家重点实验室开放基金课题(PLN2022-13);国家自然科学基金项目(52174027);四川省青年基金项目(2023NSFSC0936)。

摘　　要：通过调节关键离子的浓度,智能水驱技术能够有效提高原油采收率已经得到学术界及工业界的广泛认可,但其微观机理仍存在争议。重点研究了硫酸根离子在砂岩及碳酸盐油藏中的提高采收率效果及机理。通过长岩心驱替实验探究硫酸根离子浓度对原油采收率的影响;通过开展油水界面张力、油水界面扩张模量、接触角及液桥收缩-断裂动力学行为分析,分析硫酸根离子浓度对油-水界面及固-液界面的影响规律及机制。结果表明,在低温条件下,将海水中硫酸根离子的浓度提高3倍能有效提高Berea砂岩及Indiana石灰岩中的原油相对渗透率及采收率;其微观机理包括两个方面:①硫酸根离子提高了两种岩石表面的亲水性;②硫酸根离子不仅降低油水界面张力,而且提高了油水界面扩张模量及油水界面稳定性,从而抑制地层中“颈缩-分离”(Snap-off)行为的发生,提高原油的连续性。It is well recognized that smart waterflooding is able to enhance the oil recovery factor by adjusting the ionic composition of the injection brine in both academia and industrial area.However,there still exists debates over its underlying mechanism.Focusing on understanding the effect and the mechanism of sulfate concentration on oil recovery in both sandstone and carbonate reservoirs.Coreflooding experiments were conducted using long core samples(both Berea and Indiana limestone)to examine the sulfate concentration effect on oil recovery.Oil-brine interfacial tension,oil-brine interfacial dilational modulus,contact angle,as well as liquid bridge retraction-break dynamic behavior analysis were performed to explore the effect and mechanism of sulfate concentration on oil-brine and liquid-brine interfacial interactions.The results show that even at low temperatures,if the sulfate concentration in seawater was improved triple times,the relative permeability and oil recovery in both Berea and Indiana limestone were enhanced.The underlying mechanisms include:①the higher sulfate concentration improved the water wetness of both Berea and Indiana limestone;②the higher sulfate concentration not only decreases the interfacial tension,but also increases the interfacial dilational modulus and interfacial stability,which leads to the hindering of snap-off and improvement of the oil phase connectivity.

关 键 词：智能水驱 油-水界面 固-液界面 液桥收缩-断裂 提高采收率 

分 类 号：TQ027.6[化学工程] TE357.6[石油与天然气工程—油气田开发工程] TE39