凝析气藏临界流动饱和度实验研究  

Experimental study on critical flow saturation in condensate gas reservior development

作　　者：杨海涛[1] 王栋[1] 吕晶[1] 袁锦亮[1] 

机构地区：[1]中国石化西北油田分公司雅克拉采气厂,新疆库车842017

出　　处：《石油钻采工艺》2010年第B11期42-44,共3页Oil Drilling & Production Technology

摘　　要：一般认为,凝析气藏在衰竭开发过程中,当地层压力低于露点压力后,凝析油在地层中析出,当聚集到临界流动饱和度之后才会发生流动,但是,通过实验研究证实:当地层压力低于露点压力,凝析油析出后,在凝析油饱和度较低的情况下即可发生流动,且临界流动饱和度是在不断变化的。当凝析油饱和度达到临界流动饱和度以后,将有部分凝析油发生流动,但由于压力的衰竭,会有更多的凝析油析出,导致凝析油的饱和度仍会上升。而且,凝析油的流动与生产压差有关,当远离近井地带时,若生产压差较小,气相流速较小,即使凝析油饱和度达到临界流动饱和度,也不一定会发生流动,只有当生产压差达到一定值后,凝析油才会发生流动。研究结果可为凝析油提高采收率方案设计提供指导。It is generally believed that the condensate oil drops out of the formation when the formation pressure is below the dew point pressure during natural depletion of gas condensate reservoir.It can not flow until the critical flow saturation is reached,when its saturation usually remains high.In other words,condendate oil is able to flow and be withdrawn merely when it is saturated.However,the experimental study demonstrates that less saturated condensate oil can flow after dropping out when the formation pressure is below the dew point pressure.And the critical flow saturation keeps changing.When critical flow saturation is reached,partial condensate oil begins to flow.With the pressure damping,more condensate oil will drops out,which causes the saturation moving up.The study also finds that condensate oil flowing is related to drawdown pressure.If it is far away from immediate vicinity of wellbore,with less draw-down pressure and gas phase flow velocity,the condensate oil might not flow even though the critical flow saturation is reached,but when drawdown pressure comes to specified value.This finding contributes to preparing scheme for enhanced oil recovery of condensate oil.

关 键 词：凝析气藏 多孔介质 束缚水 临界流动饱和度 

分 类 号：TE258[石油与天然气工程—油气井工程]