摘要
针对低渗透油藏CO_(2)驱波及效率低和气窜的问题,合成一种CO_(2)/N_(2)响应性纳米SiO_(2)来控制气窜指进,增加CO_(2)驱的波及范围;利用红外光谱、热重分析等方法对合成的CO_(2)/N_(2)响应性纳米SiO_(2)进行表征研究,在分散条件下对其进行粒径分析、响应性、吸附量、分散稳定性等系统研究,并采用岩心流动装置对CO_(2)/N_(2)响应性纳米SiO_(2)分散体系进行驱油模拟实验,结果表明,CO_(2)/N_(2)响应性纳米SiO_(2)符合预期设计。分散条件下,响应性纳米SiO_(2)平均粒径为58.8 nm,具有CO_(2)/N_(2)响应性,CO_(2)吸附量可达到196.8 mmol/g,有一定的分散稳定性。3 PV的CO_(2)/N_(2)响应性纳米SiO_(2)分散体系在渗透率为5.8 mD的岩心中,封堵率为89.38%,提高采收率为15.15%,最终采收率为53.44%;CO_(2)/N_(2)响应性纳米SiO_(2)分散体系通过去质子化状态下颗粒团聚,封堵地层中的气窜通道,增加低渗流通道的驱油效果。CO_(2)/N_(2)响应性纳米SiO_(2)分散体系不仅可以有效地封堵地层中的气窜通道,而且能提高CO_(2)驱油的波及效率。
To address the low CO_(2)sweep efficiency and gas channeling in low-permeability reservoirs,this paper synthesized the CO_(2)/N_(2)responsive nano-SiO_(2)to control gas channeling and fingering and increase the swept range of CO_(2)flooding.The synthesized responsive nano-SiO_(2)was characterized by infrared spectroscopy,thermogravimetric analysis,and other methods.Systematic research was conducted on its particle size,responsiveness,adsorption capacity,and dispersion stability under dispersion conditions.Moreover,a core flow device was employed for the simulation experiment of oil displacement in the presence of the CO_(2)/N_(2)responsive nano-dispersion system.The results show that the CO_(2)/N_(2)responsive nano-SiO_(2)meets the expected design.Under the dispersion conditions,the average particle size of the responsive nano-SiO_(2)is 58.8 nm,which is responsive to CO_(2)/N_(2).The CO_(2)adsorption capacity reaches 196.8 mmol/g,which indicates dispersion stability.The 3 PV nano-dispersion system has a blocking rate of 89.38%in a core with permeability of 5.8 mD and realizes enhanced oil recovery(EOR)of 15.15%and ultimate recovery of 53.44%.In the simulated core experiment,the gas channeling channel in the formation is blocked owing to particle agglomeration of the responsive nano-SiO_(2)dispersion system at the deprotonation state,and thereby the oil displacement effect of the low-permeability channel is increased.In short,the developed CO_(2)/N_(2)responsive nano-SiO_(2)dispersion system is capable of both effectively blocking gas channeling channels in formations and enhancing the sweep efficiency of CO_(2)flooding.
作者
赖南君
郝丹
朱元强
石伟
唐雷
LAI Nanjun;HAO Dan;ZHU Yuanqiang;SHI Wei;TANG Lei(College of Chemistry and Chemical Engineering,Southwest Petroleum University,Chengdu City,Sichuan Province,610500,China;Oil&Gas Field Applied Chemistry Key Laboratory of Sichuan Province,Southwest Petroleum University,Chengdu City,Sichuan Province,610500,China)
出处
《油气地质与采收率》
CAS
CSCD
北大核心
2022年第2期77-84,共8页
Petroleum Geology and Recovery Efficiency
基金
中国石油科技创新基金项目“驱油用CO_(2)/N_(2)智能响应性纳米体系的研制与提高采收率机理研究”(2018D-5007-0207)
油气田应用化学四川省重点实验室开放基金“适用于致密油储层纳米压驱体系的构筑及排驱机制研究”(YQKF202010)。
