大庆石油地质与开发2025，Vol.44Issue(1)：114-120,7.DOI:10.19597/J.ISSN.1000-3754.202308024
混相性与重力作用对CO2驱提高采收率及储存潜力的影响
Influence of miscibility and gravity on CO2 flooding for oil recovery enhancement and storage potential
摘要
Abstract
In order to understand the influence of system miscibility and gravity on CO2 displacement efficiency and storage potential,a series of displacement experiments are designed.Optimal displacement method of CO2 flooding to enhance oil recovery is determined by comparing displacement results of various combinations of miscibility and gravity.To fully reflect the effect of gravity,long core is selected for displacement experiments of horizontal gas in-jection(no gravity effect),top gas injection(gravity as displacement force)and bottom gas injection(gravity as dis-placement resistance).The results show that,for oil recovery,CO2 immiscible flooding has the best effect of top in-jection,followed by horizontal injection,and the worst of bottom injection.When the pressure is increased enough for fluid in displacement system to be miscible,gravity has almost no effect on oil recovery of CO2 flooding.There-fore,gravity-dominated gas injection should be given priority in the case of appropriate reservoir thickness and dip when CO2 immiscible flooding is carried out.For miscible flooding,reservoir thickness and gas injection direction are no longer key factors affecting the result of CO2 displacement.For CO2 storage capacity,top gas injection with full utilization of gravity in immiscible phase can achieve maximum CO2 storage capacity.The influence of gravity on CO2 storage decreases with pressure increase.In miscible phase,CO2 storage potential is very high regardless of injection direction.The research provides basis for technique optimization and field application of enhanced oil re-covery by CO2 flooding.关键词
CO2/混相性/重力驱/采收率/CO2埋存Key words
CO2/miscibility/gravity drive/recovery/CO2 storage分类
能源科技引用本文复制引用
陈小龙..混相性与重力作用对CO2驱提高采收率及储存潜力的影响[J].大庆石油地质与开发,2025,44(1):114-120,7.基金项目
中国博士后科学基金面上项目"有机-无机复合纳米孔隙约束下CO2-ECBM流体传输机制研究"(2023M733916). （2023M733916）
