Numerical Simulations of the Migration of Fine Particles Through Porous Media

The migration of fine particles (or fines) in an oil formation may cause its damage and decrease the well production rate, as several experimental and modeling studies have shown. The major challenge in the description of fines transport is the prediction of the location where particles are blocked. Classical mathematical models consider the fines as a solute and neglect the mechanism that couples fines transport and the fluid flow, without capturing therefore the single particle motion and blockage. Recent observations carried out using microfluidic systems to observe fines migration have shown limitations on tracing particles and on the analysis of the forces acting, e.g., on a single particle. This could be overcome with simulations using a new numerical approach. In this paper, a numerical model comprising lattice Boltzmann method, immersed boundary method, and discrete element method is presented. The model was developed to study fines migration in porous media at the pore scale. By considering the two-way coupling between the liquid and the solid phase (i.e., the particle), the model is able to capture particle motion in the porous medium and the effect of the particle transport on the fluid flow. Simulation results show that the fines migration is determined by the size of the particles as well as by the structure of the porous medium. Particle blockage alters the preferential flow path and decreases the permeability of the porous medium while increasing the swept area and the oil recovery. Moreover, simulations show that the increase of the pressure drop can displace blocked particles in the porous medium throats and allow restoring the initial permeability.