低渗透各向异性油藏中五点井网优化  

Design of Five-spot Well Patterns in Low-permeability Anisotropic Oil Reservoir

作　　者：谢伟伟[1,2] 王晓冬[1] 董文秀[1] 李晨[1] 徐文丽[1] 

机构地区：[1]中国地质大学(北京)能源学院,北京100083 [2]中国地质大学(北京)非常规天然气地质评价与开发工程北京市重点实验室,北京100083

出　　处：《科学技术与工程》2017年第34期43-48,共6页Science Technology and Engineering

基　　金：国家科技重大专项(2011ZX05009)资助

摘　　要：各向异性的存在会使五点井网中位于不同方向上的生产井见水时间各不相同,造成井网的不均匀驱替,为了改善井网水驱开发效果,需要对常规五点井网进行优化设计。基于非达西渗流公式和流线积分方法,推导了各向异性油藏中考虑启动压力梯度的生产井见水时间公式,通过使位于不同渗透率方向上的生产井的见水时间相同,求得了不同方向上的注采井距之间的关系。研究表明:当井网中所有生产井工作制度均相同时,注采井距的优化主要受各向异性程度的影响,而注采压差和启动压力梯度对它的影响并不大;此外,当井网中的注采井距均已确定的情况下,还可以通过改变不同生产井与注水井之间的注采压差以达到井网均匀驱替的目的。研究成果为低渗透各向异性油藏中五点井网的合理开发提供了理论设计参考依据。For the common five-spot pattern,the existence of anisotropy can change the breakthrough times of different production wells,and lead to the equilibrium displacement. To improve the water flooding development effects,it＇s necessary to design the new well patterns reasonably. Based on the basic formula of non-Darcy flow with low velocity and the flow line integral method,considering the effects of threshold pressure gradient and degree of anisotropy,the calculation formula of breakthrough time of production well is derived. To obtain equilibrium displacement effect of well patterns,the injector-producer distances on different directions should be designed by making the breakthrough times of production wells which are located on the different permeability directions equal. The studies show： in the condition that the operation rules for all production wells are the same,the optimum design of well spacing mainly depends on the degree of anisotropy,while injection-production pressure difference and threshold pressure gradient have little influence on it. Besides,if the distances between wells have been fixed,equilibrium displacement can be also achieved by changing the values of injection-production pressure difference in different permeability directions. The research results provide a theoretical reference method to design reasonable well patterns in low-permeability anisotropic reservoir.

关 键 词：启动压力梯度 各向异性 注采压差 见水时间 井距比 

分 类 号：TE341[石油与天然气工程—油气田开发工程]