Speaker(s): Farah Al Sahyouni

Date: Thursday 16th January 2020 - 1:00 pm 

Location: Meeting room, ENSG Bat E, Nancy

Abstract:

Storage in salt caverns is currently the most efficient method for large scale storage of hydrogen. The reservoir capacity, but mainly its sealing integrity (k <2 * 10-21 m2, in undisturbed areas) are the main reasons. However, if the deviatoric stress crosses the dilatancy boundary, it resolves the deformations in the pore structure and increases the permeability. Thus, the risk of leakage increases. Our goal is to study the change of the hydraulic and mechanical properties according to the damage. Several experimental techniques were used to characterize the changes in the properties of the samples before and after the mechanical tests, on cylindrical salt cores respecting the REV. The evolution of permeability as a function of the stresses is imposed by the modifications of the rheological behavior of the salt. It follows a percolation curve and the breakthrough point is at the dilatancy boundary. The hardening stage allows a reduction of the permeability.