古龙页岩油注CO2补能提高采收率机理及参数优化
Mechanism and parameters optimization of CO2 injection for energy complement to enhance recovery of Gulong shale oil
曲方春 1刘东旭 2王青振 1佟斯琴 1邓森1
作者信息
- 1. 中国石油大庆油田有限责任公司勘探开发研究院,黑龙江 大庆 163712;黑龙江省油层物理与渗流力学重点实验室,黑龙江 大庆 163712;多资源协同陆相页岩油绿色开采全国重点实验室,黑龙江 大庆 163712
- 2. 中国石油油气和新能源分公司,北京 100007
- 折叠
摘要
松辽盆地北部古龙凹陷青山口组是陆相纯页岩型页岩油藏,储层纳米孔隙发育,渗透率极低,弹性开发地层能量衰减快,产量递减快,如何有效地补充地层能量及提高采收率是亟待解决的难题.针对古龙页岩油储层特征,开展了注CO2补能及提高采收率的分子模拟、室内实验及数值模拟研究,通过分子模拟评价了CO2的置换能力及扩散速率,通过注CO2室内实验评价了CO2与原油接触后的膨胀能力、混相压力,通过数值模拟方法对注CO2的不同注入参数进行了设计优化.结果表明:CO2对孔隙边界层具有较强的置换能力,并且具有较高的膨胀系数和较低的混相压力,在原始地层条件下即可实现混相;数值模拟设计优化单井吞吐注入速度为200 t/d,最优闷井时间为30 d,最优吞吐周期为5轮,页岩油注气吞吐可实现能量补充及增油效果,预计单井累计增油4 523 t.研究成果对古龙页岩油注气开发方案的编制具有重要的指导意义,为古龙页岩油效益开发提供了有力的技术保障.
Abstract
Qingshankou Formation in Gulong Sag in northern Songliao Basin is a continental pure shale oil reservoir with nano-pores developed and extremely low permeability,and rapid energy depletion and production decline in natural depletion development strata.How to replenish formation energy and enhance oil recovery are urgent chal-lenge.In view of characteristics of Gulong shale oil reservoir,molecular simulation,lab experiment and numerical simulation are conducted to study CO2 injection for energy complement and oil recovery enhancement.Displacement capacity and diffusion rate of CO2 are evaluated by molecular simulation,expansion capacity and miscible pressure after CO2 contacting with oil are evaluated by lab experiment of CO2 injection,and different injection parameters of CO2 are optimally designed by numerical simulation.The results show that CO2 has high displacement capacity for pore boundary layer,as well as high expansion coefficient and low miscible pressure,which can achieve miscible flooding in original formation conditions.Numerical simulation design optimized huff-and-puff injection rate for sin-gle well is 200 t/d,with optimal soaking time of 30 d and optimal huff-and-puff cycle of 5 rounds.CO2 huff-and-puff for shale oil can achieve energy complement and oil increase effect,with expected single-well cumulative incremen-tal oil of 4 523 t.The research has important guiding significance for development planning for CO2 injection devel-opment of Gulong shale oil,providing technical support for efficient development of Gulong shale oil.
关键词
古龙页岩油/CO2吞吐/提高采收率/参数优化Key words
Gulong shale oil/CO2 huff-and-puff/enhance oil recovery/parameters optimization引用本文复制引用
出版年
2025
国家科技期刊平台
NSTL
万方数据