CO_2驱三区复合油藏水平井压力动态分析  

Dynamic pressure analysis of three-zone composite horizontal well in oil reservoirs for CO_2 flooding

作　　者：姜瑞忠[1] 张海涛 张伟[1] 陈冠中[2,3] 林春阳 原建伟[1] JIANG Ruizhong;ZHANG Haitao;ZHANG Wei;CHEN Guanzhong;LIN Chunyang;YUAN Jianwei(School of Petroleum Engineering,China University of Petroleum(East China),Qingdao City,Shandong Province,266580,China;State Key Laboratory of Offshore Oil Exploitation,Beijing City,100028,China;China National Offshore Oil Corporation,Beijing City,100028,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]海洋石油高效开发国家重点实验室,北京100028 [3]中海油研究总院,北京100028

出　　处：《油气地质与采收率》2018年第6期63-70,共8页Petroleum Geology and Recovery Efficiency

基　　金：国家科技重大专项"厚层非均质性气藏产能评价及预测技术研究"(2016ZX05027-004-004);中海石油(中国)有限公司科技项目"分级组合区块深部调剖技术扩大试验研究"(YXKY-2016-ZY-02)

摘　　要：为了给油藏水平井CO_2驱开发提供理论依据,建立CO_2驱三区复合水平井模型,通过拉普拉斯变换、正交变换和数值反演等一系列数学物理方法,求解出解析解。根据流动形态特征,将试井曲线划分为9个阶段,分别是井筒储集阶段、表皮效应阶段、早期径向流阶段、线性流阶段、CO_2区平面径向流阶段、CO_2区向过渡区转移阶段、过渡区径向流阶段、过渡区向原油区转移阶段和原油区径向流阶段。对模型进行一系列敏感性因素分析,结果表明:CO_2区与过渡区半径越大,井底压差越小,越有利于CO_2注入;储容系数越大,过渡区持续时间越短;井筒储集和表皮系数越小对驱替越有利;流度比越大,过渡区持续时间越长。In order to provide a theoretical basis for the development of CO2 flooding in horizontal wells in oil reservoirs,a three-zone composite horizontal well model for CO2 flooding was proposed.A series of mathematical and physical methods such as Laplace transformation,orthogonal transformation,and numerical inversion were adopted to solve this model.According to the pressure response characteristics,the well testing curves were divided into nine stages including the wellbore storage stage,skin effect stage,early radial flow stage,linear flow stage,plane radial flow of CO2 zone,transfer stage of CO2 zone to transition zone,the radial flow in transition zone,the transfer stage from the transition zone to the crude oil zone and the radial flow in the crude oil zone.Sensitivity analysis was conducted on several influential factors,and results show that when the radius of the CO2 zone and transition zone become larger,the dimensionless bottomhole pressure difference will decrease,which is favorable for CO2 injection;the larger the storability ratio is,the shorter the flow time in the transition zone will be;the decrease of the wellbore storage coefficient and skin factor is more favorable for the displacement process;the greater the mobility ratio is,the longer the flow time in the transition zone will last.

关 键 词：水平井CO2驱 三区复合模型 试井曲线 解析解 

分 类 号：TE357.45[石油与天然气工程—油气田开发工程]