低成本速度管柱排水采气技术探讨

Discussion of the Drainage Gas Recovery Technology for Low-cost Velocity String

由于Ф38.1 mm(11/2in)速度管柱排水采气技术成本较高,在一定程度上制约了该项技术的推广和应用,首次对速度管柱的下入时机进行了分析。围绕Ф31.8 mm速度管柱的应用、材料降级、柔性管材料试验、速度管柱重复使用、工艺优化等5个方面开展了降低成本技术研究。采用Eclipse软件模拟出苏里格气田A区块直井产量递减率曲线。根据模拟曲线,选择日产气量高于q2=0.5 m3时安装速度管柱,可保证气井采用速度管柱生产后能收回成本;采用Ф38.1 mm×3.18 mm CT 70级速度管柱,最大下入深度远大于苏里格气田井深要求,因此,可以通过降低管柱管材级别来降低管材费用,节约成本。

The high cost of drainage gas recovery with the 038.1 mm velocity string restricts the extensive spread and application of the technology in some degree. An analysis of the running time of velocity string was conducted for the first time. The technological research on cost reduction was carried out, centering around the application of the Ф31.8 mm velocity string, velocity string material degrading, flexible tube material test, reuse of velocity string and technological optimization. The findings show that when daily gas production is higher than q2, installment of velocity string can ensure that cost recovering being achieved after gas well adopts velocity string for production. If the Ф38. 1 mm × 3.18 mm CT70 velocity string is adopted, its maximum running depth is far greater than the requirement for well depth in Sulige Gasfield.