RESEARCH ON CAPILLARY PRESSURE INFLUENCING PHASE BEHAVIOR OF GAS CONDENSATE

The gas condensate fluid and the porous media are an interaction system. It’s more really to reflect the phase behavior and the percolation characteristic of gas condensate, taking account of the effect of the interfacial phenomena on the phase and the percolation rule of gas condensate in the porous media. It can’t neglect the influence of capillary pressure on the phase behavior of gas condensate, especially in the lower permeability gas condensate reservoir. The phase calculation model considering capillary pressure is established in this paper. The effect of capillary pressure on the dewpoint of gas condensate, retrograde condensate is researched by the fluid composition in SPE 21428. The results show that the capillary radius and the interfacial tension determine the affecting degree, and when the capillary radius is up to the 10-8 meters quantitatively, the effect of capillary pressure on the dewpoint of gas condensate, retrograde condensate will be obvious very much.