Effect of Flow Rate and Salinity on Sandstone Permeability

Abstract

The Bentheim sandstone permeability decreases with the increase of the flow rate and decrease of the sodium chloride concentration. The SEM imagery confirms that the permeability decreases due to release of the discretely dispersed clays from the pore walls and their further re-deposition in the narrower pore throats. The injection of the 1M NaCl solution after distilled water causes some recovery of the permeability due to reduction of the bonded water layer thickness around clay particles, which plug the pore channels. While many of the discretely dispersed particles are detached from the sand grains by hydrodynamic forces, the clay pockets, being isolated by surrounding grains, exhibit very high resistance to erosion and remain well preserved even after flooding with a very high flow rate.