二氧化碳吞吐致密油藏的可动用性

Availability of CO2 huff and puff in tight reservoir

贾瑞轩 孙灵辉 苏致新 丛苏男 李杰瑞 周义博 3

中国科学院大学，北京 100190 中国科学院渗流流体力学研究所，河北 廊坊 065007 中国石油勘探开发研究院，河北 廊坊 065007 中国石油大庆油田有限责任公司勘探事业部，黑龙江 大庆 163002

University of Chinese Academy of Sciences, Beijing 100190, China Institute of Porous Flow and Fluid Mechanics, Chinese Academy of Sciences, Langfang 065007, China Research Institute of Petroleum Exploration and Development, PetroChina, Langfang 065007, China Exploration Department, Daqing Oilfield Company, PetroChina, Daqing 163002, China

针对CO2吞吐致密油藏可动用性，文中通过CO2吞吐实验、CO2驱替实验，结合核磁共振检测技术进行了研究。结果表明：注入压力、吞吐轮次对原油动用程度影响较大，焖井时间为非敏感影响因素；CO2对微米级孔喉中原油的相对动用程度为76.30%~99.54%，亚微米级孔喉为25.29%~58.72%，纳米级孔喉为6.91%~33.52%；对于注CO2开发致密砂岩油藏，微米级孔喉和亚微米级孔喉是可动原油的主要贡献者，且储层越致密，亚微米级孔喉贡献可动原油比例越高。

Aiming at the availability of tight reservoirs for CO2 huff and puff, this paper studied CO2 huf and puff experiment, CO2 displacement experiment and NMR detection technology. The results show that injection pressure and huff and puff cycle have great influence on the degree of oil production, but the time of soaking is not a sensitive factor; the relative utilization degree of CO2 to oil in micron pore throat is from 76.30% to 99.54%, submicron pore throat is from 25.29% to 58.72%, and nanometer pore throat is from 6.91% to 33.52%; for CO2 injection development of tight sandstone reservoirs, micron and submicron pore throats are major contributors to mobile oil, and the denser the reservoir is, the higher the proportion of submicron pore-throat contribution to mobile oil is.

10.6056/dkyqt202004020