倾斜井与直井气举设计差异及其敏感参数分析研究

Differences of Gas Lift Design between Deviated and Vertical Wells and the Analysis of Sensitivity Parameters

摘要: 尽管气举越来越多地被应用到大斜度井、水平井的举升采油中，但倾斜井气举设计与直井气举设计存在什么差异，这些差异随倾斜角度的增大将怎样变化，以及哪些气举设计所需参数对这种差异比较敏感，即如何对倾斜井气举设计所需参数进行合理选择，以便对倾斜井气举设计进行优化的研究较少，这也一直是倾斜井合理气举设计的难点问题。鉴于此，笔者以某油田一口倾斜井为例，通过实测数据进行了倾斜井产能预测方法优选和多相管流压力计算方法优选，然后在该基础上采用等套压降气举设计方法对比分析了倾斜井气举设计与同等条件下直井气举设计的差异，并逐一分析了各种气举设计所需重要参数分别取不同值时气举设计注气深度和产量随井斜角度的变化规律，从而得到了倾斜井气举设计的敏感性参数，可为倾斜井气举设计的参数优化和调整提供参考依据，是倾斜井气举高效生产的有力保障。

Abstract: Although gas lift technology has been applied to lift oil production in the highly deviated and ho-rizontal wells increasingly, the differences between the gas lift design of deviated and vertical wells still exist. How these differences vary with the increase of the angle of inclination, which parameters are more sensitive to the design differences and how to choose the design parameters reasonably to optimize the gas lift design in the deviated wells are all always the difficulties for gas lift design reasonable in the deviated wells and few studies have been done in this field. In view of these problems, this paper takes a deviated well of an oilfield as an example. According to the measured data, the optimum method for productivity prediction and multiphase pipe flow pressure calculation are chosen, and then on the basis of the study, the design method under same casing pressure drop is chosen to analyze the difference between the design for gas lift in the deviated and vertical wells in the same conditions. By keeping other parameters constant and only changing the value of important parameter one by one, the changing regularity of gas injection depth and production with the change of inclination angles are analyzed, and the sensitivity parameters of gas lifting design for the deviated wells are then obtained, which can provide an important reference for the optimization and adjustment of gas lift design parameters in the deviated wells, and also provide a strong guarantee for high efficiency production.