Abstract: In a condensate gas reservoir, there exist complex in-situ hydrocarbon systems and their interactions with porous media, which tend to. bringing about more complexity in phase behavior change in it. The available experiments of phase behavior change couldnt reflect the charac-teristics of condensate gas in real reservoirs due to their lower pressure and temperature. In view of this issue, a new ex perimental process that can actually reflect such a phase behavior change is developed by applying gas chromatographic technique and based on the theory of phase be-havior change for condensate gas, under the conditions of permeability of 0.01 lμm2 and PVT cell. The results show that greater influences of low permeability porous media on the phase behav ior characteristics of condensate gas. This process is indicated to be more reliable and accurate than available methods for phase-change experiment.

Key words: porous media, condensate gas, phase behav ior, phase change, gas chromatography