Effect of permeability on foam mobility and flow resistance distribution: An experimental study

Abstract

Foam injection is well accepted as an enhanced oil recovery (EOR) method. In this study, we carried out a series of core flood experiments to investigate the effect of permeability on foam flow in porous media. Foam was pre-generated in the upstream and injected into multiple 30 cm core columns. The permeability of core columns ranged from 6.8 to 4443.5 mD. Dynamic resistance factors and sectional pressure drops along the core columns were measured. The fluctuation ranges of dynamic resistance factors during the injection process were quantitatively analyzed. We also presented a parameter, distribution coefficient DRF, to evaluate the resistance distribution of foam flow in columns with a wide range of permeability. The entrance/exit effect on foam flow distribution was also discussed with the assistance of distribution coefficient DRF. Results suggest that there exists a non-monotonic relation between the steady-state mobility of foam and column permeability. Spatial distribution of foam flow resistance becomes uniform when the column permeability exceeds a certain value. The column permeability and the entrance/exit effect both have more impacts on the spatial distributions of foam flow in the low range of permeability than in the high range. Moreover, we also exhibit the differences in the foam flow characteristics which are principally caused by the effect of relative sizes between bubbles and pore structures.