致密砂岩油藏油水相对渗透率计算方法研究  

Calculation method for oil-water relative permeability in a tight sandstone reservoir

作　　者：李斌会 费春光[2] 付兰清[2] 曹维政[2] 董大鹏[2] 李宜强[1] LI Binhui;FEI Chunguang;FU Lanqing;CAO Weizheng;DONG Dapeng;LI Yiqiang(College of Petroleum Engineering,China University of Petroleum-Beijing,Beijing 102249,China;Exploration and Development Research Institute of Daqing Oilfield Company Ltd.,Daqing 163712,China)

机构地区：[1]中国石油大学(北京)石油工程学院,北京102249 [2]大庆油田有限责任公司勘探开发研究院,大庆163712

出　　处：《石油科学通报》2019年第1期83-91,共9页Petroleum Science Bulletin

基　　金：国家科技重大专项"松辽盆地致密油开发示范工程"(2017ZX05071)资助

摘　　要：以松辽盆地北部致密砂岩岩心为研究对象,开展了不同物性、不同含水饱和度下两相流拟启动压力梯度测定实验,在此基础上,建立了考虑岩石物性和含水饱和度的两相流拟启动压力梯度数学表征方法。基于非达西渗流理论,推导建立了考虑变启动压力梯度的非稳态水驱油相对渗透率数学模型,将其与拟启动压力梯度数学表征方法相结合,形成了致密砂岩储层油水相对渗透率计算新方法,并将新方法计算结果与JBN方法进行对比分析。结果显示,致密砂岩储层两相流启动压力梯度随含水饱和度增大先增加后减小,最大拟启动压力梯度与克氏渗透率之间存在很强的相关性;松辽盆地北部致密砂岩储层油水相对渗透率曲线的两相共渗区窄,水驱油效率较低,水相相对渗透率偏低,表明该储层注水开发难度较大。Using the tight sandstone cores in the Northern Songliao Basin, an experiment is conducted to determine the pseudo-threshold pressure gradient of two-phase flow under different physical properties and different water saturation. On this basis, a mathematical method for characterizing the pseudo-threshold pressure gradient of two-phase flow with rock properties and water saturation is established. We combined a mathematical model of unsteady water flooding relative permeability with a variable starting pressure gradient,(derived from non-Darcy percolation theory) with the mathematical characterization method of pseudo-threshold pressure gradient. This established a new method for calculating oil-water relative permeability of tight sandstone reservoir. The calculation results of the new method are compared with the JBN method. The achievements show that in a tight sandstone reservoir, with an increase of water saturation, the two-phase flow starting pressure gradient increases first and then decreases, and there is a strong correlation between the maximum pseudo-threshold pressure gradient and the Kleinberg permeability;The two-phase relative permeability curves of the Northern Songliao Basin tight sandstone reservoir have the following characteristics: The two-phase seepage zone is narrow, water flooding efficiency is relatively low, and the water relative permeability is low, which indicates that water flooding development is difficult.

关 键 词：松辽盆地北部 致密砂岩 拟启动压力梯度 相对渗透率 计算方法 

分 类 号：TE312[石油与天然气工程—油气田开发工程]