低渗砂砾岩油藏注CO_(2)+化学剂驱油机理  

Mechanism of Oil Displacement by CO_(2)and Chemical Agent Flooding in Low-Permeability Glutenite Reservoirs

作　　者：汤勇[1] 程民茂 秦佳正 袁晨刚 洪迎河 TANG Yong;CHENG Minmao;QIN Jiazheng;YUAN Chengang;HONG Yinghe(State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Southwest Petroleum University,Chengdu 610500,China,China;Engineering Technology Research Institute,PetroChina Southwest Oil&Gas Field Company,Chengdu 610017,China)

机构地区：[1]西南石油大学油气藏地质及开发工程全国重点实验室,成都610500 [2]中国石油西南油气田公司工程技术研究院,成都610017

出　　处：《华南师范大学学报(自然科学版)》2025年第1期51-59,共9页Journal of South China Normal University(Natural Science Edition)

基　　金：国家自然科学基金项目(51974268)。

摘　　要：低渗砂砾岩油藏具有强非均质性,注水开发困难、水驱采收率不高,单一气驱易引发气体窜流等问题,亟须研究适用于低渗砂砾岩油藏的提高采收率方法。以X油藏为例,明确了注CO_(2)+化学剂驱油机理。首先开展了注CO_(2)界面张力实验,随后开展了注化学剂界面张力实验,最后开展了注CO_(2)+化学剂提高采收率长岩心实验。结果表明:地层压力越大,CO_(2)-原油界面张力越小且随混相程度的提升而降低;化学剂可使相界面润湿接触角减小,并通过改变储层润湿性降低界面张力;注0.4 HCPV化学剂段塞+CO_(2)驱油效率最高,合理的化学剂段塞有利于抑制气窜,并扩大波及范围从而提高驱油效率。该研究为低渗砂砾岩油藏的高效开发提供理论依据,同时对CO_(2)+化学剂驱提采技术在同类油藏的进一步推广应用具有重要意义。Low-permeability glutenite reservoirs exhibit significant heterogeneity,which complicates waterflooding development,results in relatively low recovery rates,and increases the likelihood of gas channeling during gas flooding.A pressing need exists to investigate enhanced oil recovery(EOR)methods specifically suited for low-permeability glutenite reservoirs.The oil displacement mechanism of CO_(2)flooding combined with chemical agent flooding was elucidated using the X oil reservoir as a case study.An experiment was conducted to measure the interfacial tension of CO_(2)flooding,followed by an assessment of the interfacial tension of chemical agent flooding,with a long-core experiment performed to evaluate the enhanced oil recovery performance of CO_(2)and chemical agent flooding.The results demonstrate that as formation pressure increases,the interfacial tension between CO_(2)and crude oil decreases,with a further reduction observed as the degree of mixing increases.The interfacial contact angle is lowered,and interfacial tension is reduced by altering the wettability of the reservoir.The oil displacement efficiency is maximized when 0.4 HCPV chemical slugs are combined with CO_(2)injection.Appropriate chemical slugs inhibit gas channeling and extend the distribution range,thereby enhancing displacement efficiency.A theoretical foundation for the efficient development of low-permeability glutenite reservoirs is provided,with significant implications for the further promotion and application of CO_(2)and chemical agent flooding technology in analogous reservoirs.

关 键 词：低渗砂砾岩油藏 CO_(2)+化学剂驱 驱油机理 提高采收率 界面张力 

分 类 号：TE348[石油与天然气工程—油气田开发工程]