低渗透油藏压力传播特征分析

基于鸭儿峡低渗透油藏注水开发的基本生产特征,即注水压力不断升高、注水量不断降低、油井供液不足、产量递减快、采油速度低,对具体井组进行试注效果分析,发现油井主要依靠弹性介质传递能量,最终实现增油目的。针对低渗透储集层存在启动压力,且注水能量主要消耗在井筒附近,压力具有先累积后缓慢释放的传播特征,考虑到低渗透储集层压力传播特征,建议对地层进行压裂和周期注水以调整储集层压力的重新分布,降低注水井注入压力。通过对比分析周期注水与常规注水效果,发现周期注水采出程度高,开发效果好。

Analysis on Pressure Transmission Characteristics in Low Permeability Reservoirs

On the basis of the production characteristics of Yaerxia low permeability reservoirs, such as continuous increasing of the injection pressure,continuous decreasing of water injection rate, the lack of liquid supply, fast declining of production, low oil production rate and so on, the test results of the concrete well group were analyzed. It's found that the production well mainly relied on elastic medium to transfer energy, and ultimately to achieve the purpose of increasing oil. Aiming at the start-up pressure of low permeability reservoir, and the water injection energy was mainly consumed near the wellbore, the concept of pressure transmission was proposed to describe the pressure distribution characteristics of the water injection well in the near wellbore area. In order to adjust the pressure distribution of reservoir and reduce the injection pressure of injection well, the formation fracturing and cycle water injection were proposed. By comparing and analyzing the effect of cycle water injection and conventional water injection, it's pointed out that the recovery degree of cycle water injection is higher, and the development effect is favorable.