Assessment of capillary rise in rocks by Time Lapse Digital Imaging

Abstract

Solution flow can significantly influence metal recovery and kinetics in leaching, especially in heap/dump/In-situ leaching, however, the vast majority of the work in this area has focused on the inter-particle fluid flow, and only a few studies have investigated the capillary rise behaviour within rock samples. This deserves more attention because it plays a fundamental role in the recovery process and the diffusion pathways for lixiviants and reacted products. This short communication presents a simple methodology for the estimation of capillary action by testing different rock types by Time Lapse Digital Imaging. The method was sensitive to pixel variation which can be intercepted as the response in wettability variation. It can certainly be coupled with other technologies for ore characterization, such as X-ray micro-tomography, to further understand how the pore size distribution influences capillary response, and the fluid rise through pore spaces to interact with ore grains.