多孔介质对凝析气相态的影响

凝析气藏衰竭开发过程中,多孔介质中流动的凝析油气体系必然与多孔介质发生相互作用,影响凝析气在多孔介质中的相态变化规律。提出了一种新的气液相变实验方法,利用高精度的气相色谱分析技术,分析了不同衰竭压力下,凝析油气体系分别在岩心和PVT筒中发生反凝析相变后的流体组成,同时分析了多孔介质中凝析气的相变机理。实验结果表明,低渗透介质对凝析气的相态有较大影响,而高渗透介质对凝析气相态的影响不大,在工程设计中可以忽略。

Experimental study on influence of porous media on phase behavior of gas condensate

During the depletion development of gas condensate reservoir, porous media would definitely influence the phase behavior of condensate gas flowing in the porous media because of the interaction between flowing fluid and porous media. A novel experimental method for gas-liquid phase change was established. The composition changes of retrograded condensate gas flowing in core and PVT cell under different pressure were analyzed by using the high-precision chromatogram analytic technique. The phase change mechanism of gas condensate in porous media was analyzed. The experimental results show that the porous media with low permeability has heavy influence on the phase behavior of gas condensate, while the phase behavior in the porous media with high permeability is almost consistent with that in PVT cell. Therefore, the influence of porous media with high permeability on the phase behavior can be ignored in the engineering application.