含水饱和度和衰竭速度对凝析气藏油气采收率的影响

通过建立不同的衰竭速度和初始含水饱和度，设计了7组凝析气在多孔介质中的衰竭实验、相态分析实验和超声波露点检测实验，研究了油气采收率、气油比、凝析油临界流动饱和度和临界流动压力的变化规律。结果表明：随着衰竭速度增大，油气采收率下降但幅度不大，而凝析油临界流动饱和度增加，临界流动压力降低。当初始含水饱和度低于岩心束缚水饱和度时，随着初始含水饱和度增加，凝析油采收率明显增大，天然气采收率基本不变；反之，随着初始含水饱和度增加，天然气采收率增加，凝析油采收率下降但幅度不大。对于底水能量较大的凝析气藏，采气速度不宜过高，可在有效保持地层压力的前提下，在水区及时采取堵水排水措施。

Speed of condensate water saturation and failure the influence of the gas reservoir recovery efficiency of oil and gas

By the establishment of different depletion rates and initial water saturation, we designed 7 groups of experiments of condensate gas in porous media, and implemented phase state analysis and ultrasonic testing, in order to study the oil and gas recovery, gas oil ratio, gas condensate critical flowing saturation and the changing rules of the critical flow pressure. The results showed that, with the increasing of depletion rate, oil and gas recovery decreased but modest, and condensate critical flowing saturation increases, the critical flow pressure is reduced. When the initial water saturation is lower than the irreducible water saturation, withthe increasing of initial water saturation, condensate recovery increased, the gas recovery factor basically remain consistent. On the other hand, with the increasing of the initial water saturation, gas recovery increased, the condensate recovery decreased but modest. For the condensate gas reservoir with large bottom water energy, gas recovery rate is unfavorably ex- orbitant, we could adopt water drainage measures keeping formation pressure in time.