考虑压驱注水诱发裂缝影响的注水井压力分析  

Analysis of pressures in water injection wells considering fracture influence induced by pressure-drive water injection

作　　者：崔传智[1] 李怀亮 吴忠维 张传宝 李弘博 张营华[2] 郑文宽 CUI Chuanzhi;LI Huailiang;WU Zhongwei;ZHANG Chuanbao;LI Hongbo;ZHANG Yinghua;ZHENG Wenkuan(College of Petroleum Engineering,China University of Petroleum(East China),Qingdao,Shandong 266580,China;Research Institute of Exploration and Development,Sinopec Shengli Oilfield,Dongying,Shandong 257015,China)

机构地区：[1]中国石油大学(华东)石油工程学院,山东青岛266580 [2]中国石化胜利油田分公司勘探开发研究院,山东东营257015

出　　处：《油气藏评价与开发》2023年第5期686-694,共9页Petroleum Reservoir Evaluation and Development

基　　金：国家自然科学基金面上项目“致密油藏多段压裂水平井时空耦合流动模拟及参数优化方法”(51974343)。

摘　　要：压驱注水井底压力分析对压驱效果评价与储层参数反演具有重要的意义。为了获得压驱注水井井底压力响应和压驱注水产生的动态裂缝参数,从裂缝扩展角度出发,运用渗流力学理论与数值模拟方法,在考虑裂缝扩展、裂缝形态、注入流体滤失等因素影响的基础上,形成了考虑压驱注水诱发裂缝影响的注水井压力分析模型,获得了压驱注水井井底压力响应,分别分析了注入流量、产液量、地层渗透率和井距因素对压力的影响,并将其运用于实际压驱井,以验证模型的准确性。研究发现:压驱注水井流体流动分为5个流动阶段,分别为压驱起裂初期阶段、裂缝扩展阶段、线性流动阶段、过渡流动阶段和边界控制流动阶段;随着注入流量的增大,裂缝扩展阶段越明显,且产液量越大,在压驱注水后期双对数压力分析曲线上翘幅度越小。该研究对压驱注水开发低渗透油藏不稳定渗流机理的研究和认识具有重要的意义,对注水井动态裂缝对水井井底压力的影响研究具有一定意义。The analysis of the well bottom pressure of the pressure-drive injection wells is of great significance for the evaluation of the pressure-drive effect and the inversion of reservoir parameters.In order to obtain the bottom hole pressure response of pressure-drive injection wells and the dynamic fracture parameters generated by pressure drive water injection,and from an fracture propagation perspective,the seepage mechanics theory and numerical simulation method are used to form a pressure analysis model of water injection wells considering the effects of fracture propagation,fracture morphology,filtration of injected fluid and other factors,and obtain the bottom hole pressure response of pressure drive water injection wells.The effects of injection flow,liquid production,formation permeability and well spacing on pressure are analyzed respectively,and applied to actual pressure drive wells to verify the accuracy of the model.It is found that the fluid flow in pressure-drive injection wells can be divided into five flow stages,namely,initial fracturing stage,fracture expansion stage,linear flow stage,transitional flow stage and boundary controlled flow stage.With the increase of injection flow rate,the fracture expansion stage is more obvious,the liquid production is greater,and the upwarping amplitude of the double logarithmic pressure analysis curve gets smaller in the late stage of pressure drive water injection.This study is of great significance to the study and understanding of the mechanism of unstable seepage flow in low permeability reservoirs developed by pressure drive water injection,and to the influence of dynamic fractures in water injection wells on bottom hole pressure.

关 键 词：压驱 注水井 压力分析 动态裂缝扩展 压裂液滤失 

分 类 号：TE357[石油与天然气工程—油气田开发工程]