卢子建,钟陵,段晓苗,王新星,吕占佐
LU Zijian,ZHONG Ling,DUAN Xiaomiao,WANG Xinxing,Lü Zhanzuo

• 1:中国石油长庆油田公司第五采油厂

摘要(Abstract)：

为实现CO_2驱替过程中CO_2性能最大化，进一步提高CO_2驱替页岩油的采收率。提出了采用二甲醚（DME）辅助CO_2驱油方法，基于核磁共振（NMR）技术，通过开展助溶剂辅助CO_2驱替岩心实验，对比了丙烷、正己烷和DME辅助CO_2的驱油效果，明确了DME作用下CO_2对不同孔径孔隙原油的动用特征。结果表明：相比纯CO_2，摩尔分数为20%的DME-CO_2混合溶剂能够将CO_2-原油的界面张力降低45百分点，混相压力降低33百分点，原油黏度降低80百分点，可动用孔隙孔径下限由7.7 nm降至3.2 nm，页岩油采收率提高35.9百分点；并可显著提高CO_2动用小孔隙（0.9 nmIn order to maximize CO_2 performance during CO_2 displacement and further improve shale oil recovery by CO_2 flooding, dimethyl ether(DME) assisted CO_2 flooding method is proposed. Based on nuclear magnetic resonance(NMR) technology, cosolvent-assisted CO_2 flooding core experiment is performed to compare displacement effects of propane, n-butane and DME-assisted CO_2, and to determine producing characteristics of CO_2 on oil in different sized pores with action of DME. The experiment results show that, compared to pure CO_2, DME-CO_2 mixed solvent with 20% molar concentration reduces CO_2-oil interfacial tension by 45 percentage points, decreases miscibility pressure by 33 percentage points, decreases oil viscosity by 80 percentage points, decreases lower limit of producible pore size from 7.7 nm to 3.2 nm, and increases shale oil recovery by 35.9 percentage points. And it significantly improves capability of CO_2 producing micropores(0.9 nm

关键词(KeyWords)： 页岩油;二甲醚(DME);核磁共振(NMR);CO_2驱;界面张力
shale oil;dimethyl ether(DME);nuclear magnetic resonance(NMR);CO_2 flooding;interfacial tension

Abstract:

Keywords:

基金项目(Foundation): 国家科技重大专项“鄂尔多斯盆地大型低渗透岩性地层油气藏开发示范工程”（2016ZX05050）;; 中国石油天然气股份有限公司长庆油田公司科技发展部项目“长庆气田稳产及提高采收率技术研究”（2016E-0509）

作者(Author): 卢子建,钟陵,段晓苗,王新星,吕占佐
LU Zijian,ZHONG Ling,DUAN Xiaomiao,WANG Xinxing,Lü Zhanzuo

DOI: 10.19597/J.ISSN.1000-3754.202308014

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