The application of VAPEX process was carried out in sintered homogeneous and vuggy porosity media with different matrix permeability and porosity, to investigate the behavior of vapor extraction process in vuggy media as a potential recovery process. The VAPEX experiments were conducted using Cold Lake bitumen, and n-pentane as the hydrocarbon solvent. Seven different models were made, four of which were vugular media with different vuggy-to-total pore volume ratios. The vugs were arranged in aligned and staggered configurations. Three homogeneous sintered glass beads models of different permeability and porosity were also made. The vugs in sintered models were created by embedding wood particles of uniform volume (20 mm3 each) in the glass beads continuum between two parallel glass plates and by heating them in the muffle furnace. During the VAPEX experiments, analysis of the live and dead oil production rates, solvent content, and residual oil were conducted. It was observed that the vugs could appreciably facilitate the production of bitumen from the vuggy models compared to the homogeneous model with the same matrix glass bead size. The increase in the vug porosity of the porous space significantly increased the live and dead oil production rates of bitumen and slightly decreased the extent of residual oil saturation left in the model. Unlike the sintered homogeneous models in which the production rate of bitumen remains more or less constant during the VAPEX process, the vuggy porosity models display a boost in the rate of oil production when several vugs are being invaded by the solvent vapor. This behavior was more pronounced in the case of aligned vugs were the vugs were closer to each other and more vugs were invaded simultaneously compared to the staggered vug configuration. The enhanced pore-level mixing of solvent with bitumen, improved petrophysical properties of the porous medium, and the flow communication of matrix with the vugs were found to be important in draining the live oil towards the production well at higher rates.

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