低渗油藏注入水有效影响范围研究

THE EFFECTIVE IMPACTED SCOPE OF INJECTED WATER INLOW PERMEABILITY RESERVOIR

低渗透油藏最显著的特征是存在启动压力梯度,这使其在注水开发过程中渗流阻力增大、降低注入水的波及范围,在考虑流体渗流时存在的启动压力梯度影响条件下,如何准确确定注入水影响范围,是有效开发低渗油藏的关键技术之一。根据等产量一源一汇渗流理论,获得了注采单元的等最大压力梯度等值线方程,在确定低渗透油藏合理注采井距的基础上建立了考虑启动压力梯度影响的注入水有效影响范围分析理论与方法,得到不同渗透率和注采压差下注入水有效影响范围。实例应用结果表明,该方法简单实用,分析结果与油田实际情况基本一致,该方法对油田合理井距的确定有指导意义。

The low-permeability reservoir is remarkably characterized by threshold pressure gradient,which makes high filtration resistance,declines sweep scope of injected water,owing to the threshold pressure gradient in the process of the fluid flow through porous media,how to confirm the injected water effective scope is one of the key techniques to develop the low-permeability reservoir effectively.According to the theory flowing through porous media for the iso-production one source-one convergence point,the maximum compression gradient isarithmic line equation of flooding unit is obtained.On the basis of certain reasonable injector and producer distance,in this article analytic theory and method of determining the injected water effective incidence with the consideration of the influencing of the threshold pressure gradient is established and plate of injected water effective incidence under different obtained.