关于凝析气藏开采速度的讨论

在开展不同衰竭速度长岩心衰竭实验的基础之上,引入凝析油组分分析,研究不同衰竭速度对凝析气藏开发效果的影响。结果表明,凝析油中重质组分的质量分数随衰竭速度的增加而增大。开采速度对天然气的采收率影响不大,对凝析油采收率的影响非常明显;由于非平衡相变的影响,使得衰竭速度越大,气、液分离的非稳定性越强,地层反凝析油饱和度越低,累积采出的凝析油就越多;因此,较大的衰竭速度有利于提高天然气和凝析油的采收率,降低凝析气藏在地层中的反凝析液饱和度,对缓解地层反凝析污染有一定的作用。

Discussion about the exploitation rate of gas condensate reservoirs

This study evaluated the impact of depletion rate on the development effects of gas condensate reservoir through long core depletion test under different depletion rates and composition analysis. It is revealed that the values of weight fraction of heavy component in condensate oil show an increase with depletion rate. And it has been found that the depletion rate has a significant impact on the recovery factor of condensate oil while the gas has little effect. Furthermore study shows that, because of the non-equilibrium effect, the greater the production rate is, the stronger the instability of the gas-liquid separation is, the lower the retrograde condensate saturation is and the larger the cumulative recovery of the condensate oil is. So, the implementation of a fast depletion rate is favorable to improve the recovery factor of condensate oil and gas and cut down the saturation of the condensate oil in reservoir, which has a certain role to alleviate the near wellbore retrograde condensate pollution.