Solubility and thermo-physical properties measurement of CO2- and N2-Athabasca bitumen systems

The production of heavy oil and bitumen is more complex and expensive than conventional oils. One of the main reasons is that heavy oils and bitumen have high viscosity and are usually immobile at the reservoir conditions. The viscosity of heavy oil or bitumen must be lowered in order to be recoverable by an oil recovery method such as solvent injection, steam-assisted gravity drainage (SAGD), and expanding solvent SAGD (ES-SAGD). In this study we report thermo-physical properties of CO2 and N2/bitumen mixtures. Solubility of non-condensable gaseous solvents, i.e. carbon dioxide and nitrogen, in Athabasca bitumen, as well as the liquid phase density and viscosity of solvent saturated bitumen are measured at temperatures up to 190 °C and pressures up to 8 MPa. Moreover, Peng-Robinson equation of state (PR-EoS) is applied to represent the experimental solubility which shows the absolute average relative deviation (AARD) of 4.3% and 7.6% for CO2 and N2, respectively. These findings will find many applications in the design and simulation of heavy oil and bitumen recovery processes.