摘要
为了弄清疏松砂岩稠油油藏反九点井网至排状加密后的剩余油分布规律,采用基于实际井组物性特征的三维大尺寸物理模型,进行反九点井网加密前后的流场变化及驱油效率实验,研究反九点井网至排状加密后的压力场、饱和度场以及驱油效率的变化。加密前物性越好的区域驱油效率越高,驱油效率增长率越大。加密后,在一定渗透率范围内,由于水窜的影响物性越好的区域驱油效率反而越差;反九点井网排状加密、生产井转注可以有效改善水驱控制程度,提高油藏驱油效率,加密后采收率提高了11.8%。对于有边底水的油藏,加密前剩余油纵向上在中、上部层位富集,平面上分布在物性较差的区域以及边角井之间的区域;加密后,剩余油主要分布在生产井排的加密井与原生产井之间的低渗透带。
To better understand the remaining oil distribution in heavy oil reservoir with the unconsolidation sandstone before and after the infilling of the inverted nine-spot well pattern,the physical experiments were conducted to analyze the flow field and displacement efficiency after the infilling of inverted nine-spot well pattern using the three-dimensional physical model based on the practical reservoir petrophysical characters in well group.The variation of the pressure field,saturation field and displacement efficiency were obtained and analyzed after the infilling of inverted nine-spot well pattern.Before infilling,the regions with better reservoir properties have higher displacement efficiency and bigger growth rate of displacement efficiency.After infilling,the displacement efficiency became lower because of the water breakthrough at the area with better reservoir properties within a certain range of permeability.Infilling of well pattern and changing producers to injectors can improve the controlling degree of the water flooding and enhance oil recovery of 11.8%.For the reservoirs with the edge and bottom water before infilling,the remaining oil is vertically enriched in the middle and upper layers,and the remaining oil is horizontally distributed in the areas with the poor reservoir properties and regions between the edge wells and corner wells.After infilling,the remaining oil is distributed in the low-permeability regions between the producers and infill wells.
作者
熊钰
徐宏光
王玲
周文胜
刘晨
XIONG Yu;XU Hongguang;WANG Ling;ZHOU Wensheng;LIU Chen(Petroleum Engineering School,Southwest Petroleum University,Chengdu City,Sichuan Province,610500,China;Nanchong Vocational and Technical College,Nanchong City,Sichuan Province,637000,China;CNOOC Research Institute,Beijing City,100027,China)
出处
《油气地质与采收率》
CAS
CSCD
北大核心
2020年第3期70-78,共9页
Petroleum Geology and Recovery Efficiency
基金
国家科技重大专项“大型油气田及煤层气开发”(2016ZX05025-001-004)。
关键词
反九点井网
加密
流场
驱油效率
剩余油
inverted nine-spot well pattern
well pattern infilling
flow field
displacement efficiency
remaining oil
