摘要
针对文南油田文 72块沙三段中亚段低渗透油藏 ,开展了烃气驱提高采收率可行性研究。研究认为 ,在目前地层条件下 ,虽然拟定的注入溶剂与该块油藏原油形成 4 7.10MPa的最小混相压力不能达到完全混相 ,但驱替效率较高 ;长岩心驱替特征则表明该体系是一个近混相体系 ,与相同条件下的氮气驱和水驱相比 ,采收率分别提高了38.4 3%和 2 2 .0 8% ;影响气驱采收率的主要因素是“混相”程度和气窜问题 ;水气交替注入可较大幅度提高采收率 ,但注入压力很高 ,现场实施困难。
Feasibility study on hydrocarbon gas drive for enhancing oil recovery is carried out in middle Es 3 lowpermeability oil reservoirs of Wen 72 block in Wennan oilfield. It is considered that injected solvent and the crude oil in this reservoir can′t be miscible completely for 47.10 MPa threshold miscible pressure under present formation conditions, but displacement efficiency is high. Displacement characteristics of long cores show that it is a near miscible system that the recovery efficiency is higher 38.43% and 22.08% than that of nitrogen drive and water drive at the same conditions. The main factors of influencing the recovery efficiency of gas drive are 'miscible' degree and gas channeling. Alternating injection of water and gas may enhance recovery efficiency by a big margin, but it is difficult of the field application for very high injection pressure.
出处
《油气地质与采收率》
CAS
CSCD
2003年第1期62-64,共3页
Petroleum Geology and Recovery Efficiency
