摘要
常用的低渗透致密油藏动用半径计算方法未考虑地层渗透率和流体黏度的变化,影响了结果的准确性。建立考虑启动压力梯度、渗透率及原油黏度随地层压力变化的致密油藏动用半径计算模型,并采用数值分析的迭代法对模型进行了求解,分析启动压力梯度、压力敏感系数、黏度变形系数、生产压差等关键参数对油井动用半径的影响。结果表明,启动压力梯度越大,流体的非线性流动越强,油井动用半径越小;随着生产压差的增大动用半径增大,同时,压力敏感系数对动用半径的影响也越来越大;黏度变形系数越大,导致渗流阻力增加,油井动用半径越小。研究成果应用于BZ油田开发方案制定,确定合理生产压差为8~10 MPa,合理注采井距约为200~250 m。该方法对于低渗透致密油藏开发方案制定具有一定指导意义。
To address the issues in calculating the dynamic drainage radius of low-permeability tight oil reservoirs,a model considering the startup pressure gradient,permeability,and variations in crude oil viscosity with reservoir pressure was established.The model was solved using numerical analysis iterative method,and the effects of key parameters such as startup pressure gradient,pressure sensitivity coefficient,viscosity deformation coefficient,and production pressure difference on the drainage radius of oil wells were analyzed.The results indicate that the larger the startup pressure gradient,the stronger the non-linear fluid flow and the smaller the drainage radius of oil wells.As the production pressure difference increases,the drainage radius also increases.As the production pressure difference increases,the drainage radius increases.When the production pressure difference is small,the influence of the pressure sensitivity coefficient on the drainage radius is relatively small,but as the production pressure difference increases,the impact of the pressure sensitivity coefficient becomes more significant.The higher the viscosity deformation coefficient,the larger the flow resistance and the smaller the drainage radius of oil wells.The research findings were applied to designing development plan for the BZ Oilfield,where a reasonable production pressure difference of 8~10 MPa and an injection-production well spacing of approximately 200~250 meters were recommended.The design of injection-production well spacing and reasonable working system for oil wells achieved favorable results,which provides a guidance for the design of development plans for tight oil reservoirs.
作者
姜永
吴浩君
高振南
杨晨旭
JIANG Yong;WU Haojun;GAO Zhennan;YANG Chenxu(Tianjin Branch of CNOOC Ltd.,TianJin 300459,China)
出处
《油气井测试》
2024年第3期8-12,共5页
Well Testing
基金
中海石油(中国)有限公司重大专项“渤海中深层复杂油气藏高效开发技术”(CNOOC-KJ135 ZDXM36TJ03TJ)。
关键词
致密油藏
动用半径
启动压力梯度
压力敏感效应
黏度变形系数
生产压差
低渗透
非达西渗流
tight oil reservoir
drainage radius
startup pressure gradient
pressure sensitivity effect
viscosity deformation coefficient
production pressure difference
low permeability
non-Darcy flow
