基于核磁共振与微观数值模拟的CO_(2)埋存形态及分布特征研究  

CO_(2) sequestration morphology and distribution characteristics based on NMR technology and microscopic numerical simulation

作　　者：陈秀林 王秀宇 许昌民[1,2] 张聪 CHEN Xiulin;WANG Xiuyu;XU Changmin;ZHANG Cong(State Key Laboratory of Petroleum Resources and Prospecting,China University of Petroleum(Beijing),Beijing 102249,China;College of Petroleum Engineering,China University of Petroleum(Beijing),Beijing 102249,China)

机构地区：[1]中国石油大学(北京)油气资源与探测国家重点实验室,北京102249 [2]中国石油大学(北京)石油工程学院,北京102249

出　　处：《油气藏评价与开发》2023年第3期296-304,共9页Petroleum Reservoir Evaluation and Development

摘　　要：CO_(2)排放加剧,环境问题日益严峻,碳减排刻不容缓。CO_(2)-EOR是地质封存CO_(2)的主要手段,但国内外针对CO_(2)-EOR方面的研究大多是对剩余油进行研究,驱油时针对CO_(2)埋存形式的相关研究较少。研究利用核磁共振技术结合数值模拟手段,分析不同岩心饱和油进行气驱后CO_(2)埋存形态及分布特征,结果表明:核磁共振技术结合微观气驱油数值模拟方法可以分析CO_(2)的微观埋存形态,岩心中CO_(2)驱替原油时,首先进入大孔道驱油,大孔隙中的压力达到一定程度后,原油向周围毛细管力分布不均的小孔喉流动,气体不断驱动原油,直到小孔压力累计至一定值小孔隙内原油才被驱走。数值模拟采用COMSOL Multiphysics软件进行,微观模拟结果显示大孔道中CO_(2)主要以连片的自由气形态存在,而细小孔隙中CO_(2)首先以溶解形式留存,大小孔隙中均没有完全以自由气或溶解气埋存的CO_(2)。Under the situation of intensifying CO_(2) emissions and increasingly serious environmental problems,carbon emission reduction is urgent.CO_(2)-EOR is the main means of geological storage of CO_(2),but most of the researches on CO_(2)-EOR at home and abroad are to study the residual oil,and there are few studies on the form of CO_(2) storage during oil flooding.In this paper,nuclear magnetic resonance is used to detect CO_(2) displacement online combined with numerical simulation is used to study the CO_(2) storage morphology and distribution characteristics of different core saturated oil after gas flooding.The results show that the NMR technology combined with the microscopic gas flooding oil numerical simulation method can effectively study the microscopic storage morphology of CO_(2).When CO_(2) in the core replaces crude oil,it first enters the large pore to drive oil,and after the pressure in the large pore reaches a certain level,the crude oil flows to the small hole throat with uneven distribution of capillary force around it,and the gas continues to drive the crude oil until the small pore pressure accumulates to a certain value in the small pore.Numerical simulations are performed using COMSOL Multiphysics software.Microscopic simulation results shows that CO_(2) in large pores mainly exists in the form of continuous free gas,while CO_(2) in small pores is first retained in dissolved form.There is no CO_(2) completely stored in free gas or dissolved gas in both large and small pores.

关 键 词：CO_(2)驱油 非混相 CO_(2)微观埋存 核磁共振 数值模拟 

分 类 号：TE312[石油与天然气工程—油气田开发工程]