页岩油压闷采渗流机理的格子Boltzmann模拟  

Shale oil flow mechanisms during fracturing-soaking-producing process studied by Lattice Boltzmann simulation

作　　者：杨雨萱 王森[1,2] 陈李杨[3] 刘祖鹏 冯其红[1,2,4] YANG Yuxuan;WANG Sen;CHEN Liyang;LIU Zupeng;FENG Qihong(School of Petroleum Engineering,China University of Petroleum(East China),Qingdao 266580,China;State Key Laboratory of Deep Oil and Gas,China University of Petroleum(East China),Qingdao 266580,China;Exploration and Development Research Institute,Shengli Oilfield Company,SINOPEC,Dongying 257015,China;Shandong Institute of Petrochemical Technology,Dongying 257061,China)

机构地区：[1]中国石油大学(华东)石油工程学院,青岛266580 [2]中国石油大学(华东)深层油气全国重点实验室,青岛266580 [3]中国石化胜利油田分公司勘探开发研究院,东营257015 [4]山东石油化工学院,东营257061

出　　处：《石油科学通报》2025年第2期298-308,共11页Petroleum Science Bulletin

基　　金：国家自然科学基金项目(52274055);泰山学者工程专项经费(tsqn202408088);山东省自然科学基金项目(ZR2022YQ50)联合资助。

摘　　要：页岩油是我国潜力最大、最具战略性的石油接替资源之一,厘清压闷采过程中多孔介质内流体分布演化规律对提高页岩油采收率具有重要意义。本文采用多组分多相格子Boltzmann模型对页岩油压闷采过程中的渗流机理开展研究。首先使用Laplace定律、接触角、分层流动验证了模拟模型的准确性。随后基于济阳页岩扫描电镜图像,构建了包含顺层缝、网状缝和基质孔隙分布的页岩多孔介质结构。利用格子Boltzmann模型对页岩多孔介质内压闷采过程开展模拟,分析了压闷采不同阶段的流体分布特征,探究了不同闷井时间、储层润湿性和排液速度的影响。结果表明闷井阶段压裂液会在毛管力作用下渗吸进入网状缝并将内部的油相置换出来,随着闷井时间增加压裂液返排率趋于减小;水湿岩心相较于中性和油湿岩心具有更好的开发效果,压裂液利用率和基质内原油动用程度更高;较高的排液速度会使孔隙内的压力快速下降,不利于后续页岩油的生产。本文从孔隙尺度研究了页岩油压闷采过程中流体流动机理,为页岩油井合理生产制度的制定提供了支撑。Shale oil is one of the most potential and strategic alternative oil resource in China.It’s of great significance to clarify the fluid distribution and evolution laws in porous media for enhancing the recovery of shale oil during the fracturing-soak-ing-producing process.In this work,a multi-component multiphase lattice Boltzmann model was adopted to study the shale oil flow mechanism during fracturing-soaking-producing process.Firstly,the accuracy of the model was verified using Laplace’s law,contact angle,and stratified flow.Then,based on the scanning electron microscope(SEM)image of Jiyang shale,the struc-ture of the shale porous medium was constructed including the distribution of fracture and matrix pores.Subsequently,the lattice Boltzmann model was used to simulate the fracturing-soaking-producing process of shale porous media,and the fluid distribution characteristics at different stages were analyzed.Then the effects of different soaking time,reservoir wettability and drainage rate were explored further.The results show that the fracturing fluid will seep into the matrix pore and replace the oil phase under the action of capillary force during the soaking stage,and with the increase of soaking time,the backflow rate of fracturing fluid return tends to decrease;the water-wet core has a better development effect than the neutral and oil-wet cores,and the utilization rate of fracturing fluid and the degree of crude oil utilization in the matrix are higher;the higher drainage rate will make the pore pressure drop rapidly,which is not conducive to the development and production of the shale oil.The fluid flow mechanisms during the shale oil fracturing-soaking-producing process are investigated from a pore-scale perspective,which provides support for the formulation of a reasonable production schedule for shale oil wells.

关 键 词：页岩油 格子BOLTZMANN方法 自发渗吸 纳米孔隙 多组分多相 

分 类 号：TE312[石油与天然气工程—油气田开发工程] O359[理学—流体力学]