Application of PC-SAFT Equation of State to Bitumen/Solvent Systems

摘要

Perturbed-Chain Statistical Associating Fluid Theory (PC-SAFT) has shown promising results in the study of phase equilibrium and density for light and heavy oils. This thesis works to develop the application methodology of the simplified PC-SAFT to bitumen/solvent systems.;A new binary interaction coefficient (kij) correlation to temperature and molecular weight was proposed. The average absolute relative deviation (AARD) in pressure with the new correlation was only 3.6% for more than 2,000 vapour-liquid equilibrium data, including 49 CH4, C2H6, and CO2 binaries with n-alkanes up to n-C44H90. The predictive ability of the new correlation was verified by predicting the phase equilibrium, saturated density, and viscosity of various asymmetric systems.;A new eight-pseudo-component characterization (8-PCs) for the simplified PC-SAFT was developed for different Alberta bitumens using distillation and molar mass data. It was applied to model the density and solubility of Athabasca and Peace River Bitumens with different solvents. Viscosity was modeled using PC-SAFT coupled the Expanded Fluid Viscosity theory. The AARDs were within 2.3% for the density, within 6.6% for the solubility, and 14.6% for the viscosity.;The characterization method was applied to model multi-phase equilibrium and density. The onset pressures of the second liquid phase for bitumen/solvent systems were very close to the vapour pressures of the pure solvent. In addition, the mutual solubility and density of bitumen and C2H6 were modeled. The solubility AARD was 2.6%, and the density AARD was 1.5%.;The simplified PC-SAFT was integrated into reservoir simulation using a three pseudocomponent (3-PCs) characterization. Data for the K-Value, density, compressibility, and thermal expansion coefficient were generated to model warm C3H8 VAPEX experiments at 40°C, 50°C, and 60°C. The reservoir simulation results indicated good agreement with the measured data.;The proposed bitumen characterization for the simplified PC-SAFT is accurate and reliable. The achievements of this work can be directly applied to simulate the phase behaviour and recovery of bitumen and solvents.