Seminar Walid Okaybi

Abstract

The transport of colloidal particles in porous media is a complex process that depends on many physical phenomena. Successive particle depositions on pore walls can lead to clogging processes leading to a reduction in permeability, which considerably reduce the yield of geothermal wells.

Physical clogging processes rely on the interplay between hydrodynamics (pore geometry, flow rate, suspension concentration) and surface forces (particle-particle and particle-wall interactions). We investigated the impact of each parameter separately on particle depositions in single pore microchannels using microfluidic devices as a model porous media. The preparation of microfluidic chips and colloidal suspensions were described, and an experimental protocol to investigate pore-clogging mechanisms was achieved. It was shown that more particle depositions was observed for high ionic strength and high particle suspension concentration. It was also observed that less particle depositions were encountered at higher applied pressure. As variations in geometric parameters of pore geometries was not yet investigated, an updated set of single pore microchannels is in process of fabrication.