PHASE-BEHAVIOR OF RESERVOIR FLUIDS .2. SUPERCRITICAL CARBON-DIOXIDE AND BITUMEN FRACTIONS

Mutual phase equilibrium solubilities have been measured for supercritical CO2 and bitumen fractions up to 250°C and 16 MPa. Two approaches to modeling the distribution coefficients, based on the Perturbed Hard Chain (PHC) and Soave equations of state, have been found to describe adequately the condensed phase. However, PHC is better for predicting the vapor phase compositions, except in the near-critical regions. Furthermore, unlike Soave, the PHC binary parameters can be generalized as functions of temperature and molecular weight, in a way which is consistent for the fractions and total bitume. © 1990.