调堵结合技术可行性研究及参数优化

调剖堵水作为常用的稳油控水技术,对于油井稳产起到重要的作用,但是由于国内油层非均质严重,加上多轮次调剖作业,使得调堵效果变差,有效期缩短;拟将调剖和堵水技术相结合,在优选得到的调剖剂和堵水剂基础上,对高强度凝胶调剖剂微观成胶结构进行了电镜分析,采用室内岩心实验,对注水井调剖结合采油井堵水的方法的可行性进行评价,并对调堵结合用量和顺序进行优化。研究结果表明,堵剂微观结构密实,具有良好的注入选择性和封堵能力,调堵结合増油效果明显好于单独调剖或堵水,且调堵结合宜采用"先调后堵"的方式,以0.2 PV调剖剂+0.1 PV堵水剂的用量的驱油效果最好。实验研究的结果对于改善调堵效果和方案设计提供了技术思路和参考依据。

Study on Feasibility of Profile Control Combined with Water Shutoff and Parameters Optimization

Profile control and water shutoff are two of common technologies to decrease water-cut and sustain oil production. Because of severe original heterogeneity and long-term water flooding, multi-round profile controls make the effect worse and shorten the validity. Here, combining profile control work over from injection wells and water shutoff from production wells can be a candidate to control the water production. Based on the screened profile control and water shutoff agents, the microscopic structure of the gel as profile control agent was observed by electron microscope. Also, the feasibility of combining profile control with water plugging was evaluated by core flooding tests. Meanwhile, the slug size and injecting sequence of water control agents were optimized. The results showed that, the recovery of combination of water shut off with profile control is higher than one of them. For the investigated profile control agents, the tight microstructure can be observed, which ensured the high plugging intensity. Combining 0.2 PV profile control and 0.1 PV water shutoff agents can achieve high oil production, and it is recommended to inject water shutoff after profile control. The laboratory results are helpful for improving water control effect and providing the data for project design.