VAPOR-LIQUID-EQUILIBRIUM IN A 6-COMPONENT SIMULATED SOUR NATURAL-GAS SYSTEM AT SUB-AMBIENT TEMPERATURES

Equilibrium phase composition and refractive index measurements were made on a synthetic sour gas mixture at 8 different conditions over a temperature range from 185.95 to 235.90 K at pressure from 2.74 to 8.04 MPa. In addition, the volume percent liquid at five pressures and the upper retrograde dew point were measured at 235.90 K. The refractive index measurements were used together with the phase compositions to calculate the equilibrium phase densities. These were then used with the overall material balance relationships to calculate the phase volumes. In all but one case, the directly observed liquid volumes agreed well with the calculated values. The disagreement in the results observed near the critical point illustrates the limit of applicability of the method. © 1979.