Numerical and experimental investigation of dispersed oil-in-water flow in porous media

Reservoir heterogeneity continues to be a major challenge in the oil industry's efforts to minimize the water cut, improve the volumetric sweep efficiency, and, ultimately, increase oil recovery. Injection of oil-in-water (O/W) dispersions can regulate the permeability contrast between these layers. Dispersed oil droplets can propagate into the reservoir and partially plug porous spaces in high-mobility zones. This study is devoted to highlighting a number of areas where there is a lack of knowledge concerning O/W dispersion injection in porous media in order to evaluate the entrapment mechanisms, pressure drop, and permeability reduction. A series of O/W dispersion injection experiments were conducted on various cylindrical sandstone core plugs. The effluent shows a significant decline in oil droplet size. A mathematical model based on the experimental setup was developed to describe the dynamics of the dispersion flow. The finite element method (FEM) was employed to numerically solve the governing equations. The numerical model involves the discretization of convection-diffusion, modified Darcy, and pressure equations. Verification of the numerical model was performed by comparing the pressure drop and permeability decline to the results of analytical solutions. The model was validated relatively well against experimental data. Finally, the current study provides a fundamental insight into a number of factors that may influence O/W dispersions flow in porous media. However, further research and improvements to the model complexity are required for field applications.