随着水平井开采技术和低渗透油气田开发理论的发展,利用水平井开发低渗透油气田是提高低渗油气田采收率的重要手段。然而,在过去的研究里,水平井主要是作为生产井,水平井作为注水井的研究尚少。水平井注水开发技术为低渗透油藏的合理开发提供了新思路。本文利用叠加原理,建立了分段射孔水平井三维注入能力的评价模型,分析了当量井径与实际射孔段长度和水平井所处的位置的关系,讨论了水平井流量的分布,研究了水平井在注水开发中的压力分布,并将上述理论研究应用于大庆榆树林油田。研究结果表明,该模型对于低渗透油藏中的水平井注水技术具有重要的指导意义,具有一定的推广价值。
With the rapid development of horizontal well technology and the theory of low permeability reservoir exploration, applying the horizontal well to explore low permeability reservoir is an important measure for improving the recovery efficiency of the low permeability reservoir. However, in the previous research, horizontal well is regarded as the production well. Thus the research on the horizontal well as an injection well is rare. Consequently, the water injection technology of the horizontal well provides a new idea for the reasonable exploration of the low permeability reservoir. Considering the current research situation, a 3-D model about the injection capacity evaluation of selective perforation horizontal well is established based on the principle of superposition. The relationship between equivalent radius and perforation length as well as the location of the horizontal well is analyzed; the distribution of the flow and pressure for the horizontal well is discussed based on the established model. All the foregoing theoretical research is applied to the Yushulin Block of Daqing Oilfield and the result indicates that due to its accuracy and reliability, the established model has the important significance of guidance and popularization value for the horizontal well injection exploration of the low permeability reservoir.