MODELING THE DISSOLUTION OF A STATIC AND RISING CO2 BUBBLE INTO ATHABASCA BITUMEN

The dissolution of a single CO2 bubble into Athabasca bitumen was mode lled for the cases of static and rising bubbles. The models for the di ssolution of the static bubble included a quasi-stationary model and a simpler molecular diffusion model. For the rising bubble, the models were based on Brian-Hales'/Levich's Nusselt number correlations and Hi gbie's penetration theory. The predictions for the static bubble case, over a temperature range of 300-400 degrees K and a pressure range of 1 - 6 MPa, suggest that the diffusion is entranced at lower temperatu res and higher pressures due to the high CO2-solubility in bitumen. Th e dissolution of the rising bubble is predicted to be influenced by bo th molecular and convective diffusion, leading to a much faster bubble dissolution as compared to the static bubble. Due to a combination of effects, the models predict a minimum to exist in the dissolution tim e for the rising bubble with respect to temperature.