Computational modeling of reactive multi-phase flows in porous media: Applications to metals extraction and environmental recovery processes

A computational modeling framework is described for the analysis of multi-phase flows in reactive porous media targeted at the metals recovery through stockpile leaching and in environmental recovery processes. These systems involve a complex suite of interacting fluid, thermal and chemical reaction physics in complex geometries, which in the case of heap leaching actually grow with time, and varying environmental conditions. The computational models of such processes need to account for variably saturated liquid flow in porous media, gas flow through porous media, together with the transport of many species in one of these fluid phases plus multi-phase heat transfer and mass transfer arising from a range of phase change and gas–liquid–solid chemical reaction processes. This contribution describes just such a development of a three dimensional modeling framework which is applied to the heap leaching of gold, silver and copper in a variety of contexts.