大牛地气田水平井合理注甲醇量的确定方法

Determination of Reasonable Methanol Injection Rate in Horizontal Well in Daniudi Gas Field

越冬生产期间气井堵塞以水平井为主,达到合理的单井注甲醇量是解决水平井大面积堵塞的最有效方法。应用Plackett-Burman实验统计分析法,获得了各堵塞影响因子的敏感程度,结合该结果对水平井进行分类和典型井的选取,利用Pipesim软件建立典型单井地面输气模型,确定各类井的合理注醇量。结果表明,该典型井选取方法灵活易操作,可针对实际气井情况进行多次细分,使典型井更具有代表性;对堵塞影响最显著的因子是环境温度与产液量,其次是污水含醇率与井口油压;获得的注醇建议表给出了每类井的合理注醇量。研究结果应用于实际生产,取得了显著效果。

During winter production,horizontal gas well is often blocked. Reasonable methanol injection rate is the most effective approach to address large-scale blocking of horizontal wells. With the Plackett-Burman statistical analysis,sensitivity of each influencing factor for blocking is obtained. On this basis,horizontal wells are classified and typical wells are selected. With Pipesim software,a typical sing-well gas transmission model is built to decide the reasonable methanol injection rate. The result indicates that,the selection method of typical wells is flexible and easy,and can be used to select more representative typical wells by multiple subdivisions; the most sensitive factors are ambient temperature and fluid production,followed by methanol content in sewage and wellhead tubing pressure. The recommended methanol table gives reasonable injection rate for each kind of well. The research results have been effectively referred in practices.