特种油气藏2025，Vol.32Issue(3)：76-85,10.DOI:10.3969/j.issn.1006-6535.2025.03.009
CO2交替烷烃气吞吐提高致密油采收率实验
Experimental study on enhancing tight oil recovery by CO2-alternating-alkane huff-n-puff
摘要
Abstract
To address the decline in single-cycle recovery and the slowdown in cumulative recovery increase during the later stage of gas huff-n-puff,CO2,methane,ethane,and propane were selected to carry out extraction experi-ments using a high-temperature and high-pressure reactor,and gas chromatography was employed to determine the oil components extracted with different gases.Combined with the viscosity changes of the remaining oil after extrac-tion,the molecular mass selectivity of different gases was compared.Moreover,CO2 huff-n-puff and CO2-alterna-ting-alkane huff-n-puff experiments were conducted to evaluate the recovery enhancement effects of different injec-tion methods.The experiments revealed that propane has the highest extraction rate,reaching 62.60％at 30 MPa,ethane and CO2 achieve 53.07％and 49.25％respectively at 30 MPa,and methane has the poorest extraction abili-ty,only 20.47％at 30 MPa.Propane shows the most uniform molecular mass selectivity,extracting all oil compo-nents,and ethane preferentially extracts light and medium components,mainly those within C25,while CO2 and methane mainly extract light components within C15.The huff-n-puff experimental results showed that CO2-alter-nating-alkane huff-n-puff enhances recovery by over 10％compared to CO2-only huff-n-puff,with significant improvements in later-stage recovery per cycle.This research offers valuable insights for enhancing tight oil recovery.关键词
致密油/气体吞吐/分子质量选择性/提高采收率/萃取率Key words
tight oil/gas huff-n-puff/molecular mass selectivity/recovery enhancement/extraction rate分类
能源科技引用本文复制引用
李志浩,皮彦夫,刘丽,杨佳雯,蔡冬蕊..CO2交替烷烃气吞吐提高致密油采收率实验[J].特种油气藏,2025,32(3):76-85,10.基金项目
国家自然科学基金"低渗砂岩储层水盾对CO2-原油最小混相压力的影响机理与规律"(52174023) （52174023）
黑龙江省自然科学基金"低渗砂岩油藏水盾阻隔效应对CO2-原油MMP影响机理"(LH2021E015) （LH2021E015）
