确定凝析气井合理产能的新方法

A new way of determing reasonable productivity for condensate gas well

在凝析气藏开发过程中,随着地层压力下降,反凝析油会在井底周围聚集,形成反凝析油污染,伤害地层渗透率。凝析气井合理产能是保障高效开发凝析气藏的重要参数。基于凝析油气体系在恒温条件下的反凝析渗流理论,考虑"地层—井筒—井口—地面定点"连续流动,研究了凝析气井在不同配产条件、不同生产时间下凝析油饱和度分布特征和多项渗流特征的计算分析方法。在综合分析凝析气井各种约束条件的基础上,建立了考虑凝析油污染条件下凝析气井动态优化配产理论与方法。大港油田某凝析气藏实例计算表明,采用考虑凝析油污染条件下凝析气井动态优化配产理论与方法确定出的凝析气井合理产量与实际气井产能基本一致,说明该方法具有可靠性和实用性。

In the course of condensate reservoir development, with the decline of formation pressure, the retrograde condensate oil will be accumulated near the bottom hole, which will damage the formation permeability. The reasonable productivity is one of the most important parameters for guaranteeing the condensate gas reservoir to be developed efficiently. Based on the retrograde fluid flow theory for gas condensate system at constant temperature, considering continuous flow course from formation, bottom hole, well head to land surface, it is presented here the calculation of condensate saturation distribution and multiphase fluid flow characteristic for a condensate gas reservoir at different production rate and production time. The dynamic optimization allocation theory is presented, in which the permeability damage caused by condensate oil has been taken into account. The application in the Qianmiqiao condensate gas reservoir shows that the reasonable productivity derived by the dynamic optimization allocation is almost the same as practical productivity of the condensate gas well, suggesting that the method is reliable and applicable.