Abstract:

Taking the ultra-low permeability cores of Huabei Oilfield as an example, a new method for testing relative permeability was established on the basis of nuclear magnetic resonance and physical simulation of low-permeability reservoir. The analyses on the relationship between T₂ geometric mean value and displacement efficiency show that the new method for testing the relative permeability of the ultra-low permeability reservoir has more accurate results in tests of irreducible water saturation and residual oil saturation. The permeability has the poor correlation with T₂  geometric mean value, imbibition efficiency, expulsion efficiency and total oil displacement efficiency. The T₂  geometric mean value has the excellent relationships with the movable fluid percentage, imbibition efficiency, expulsion efficiency and total oil displacement efficiency.

Key words: ultra-low permeability reservoir, relative permeability, oil-displacement efficiency, permeability curve, testing method, physical simulation experiment

摘要：

以华北油田特低渗透岩样为例，利用低磁场核磁共振仪，并依据低渗透物理模拟实验，建立了特低渗透油田相对渗透率曲线测试新方法。并对不同渗透率条件下T₂几何均值与驱油效率的关系研究表明，与常规相对渗透率曲线测试方法相比，特低渗透油田相对渗透率曲线新测试方法能比较准确地测试了束缚水饱和度和残余油饱和度。渗透率与T₂几何均值、渗吸效率、驱替效率和总的驱油效率的相关关系较差，T₂几何均值与可动流体百分数、渗吸效率、驱替效率和总的驱油效率有很好的相关性。

关键词: 特低渗透油田, 相对渗透率, 驱油效率, 渗透率曲线, 测试方法, 物理模拟实验