Relevance of Hydro-Mechanical-Chemical Processes Involved in the Construction and Operation of Copper Heap Leach Pads

M. Tincopa[1], A. Nardi[2], G. Roman-Ross[2] , J. Molinero[2]
[1]Technic University of Catalonia (UPC), Barcelona, Spain
[2]Amphos 21 Consulting, Barcelona, Spain
Published in 2013

Heap leaching in the mining industry had become a sophisticated practice at least 500 years ago. It is a mineral processing technology whereby piles of crushed Run-of–Mine rock are leached with chemical solutions to extract minerals. The goal of this work is to contribute to the understanding of the behavior of a heap leach pad by using coupled Hydro-Mechanical-Chemical simulations. COMSOL Multiphysics® is able to solve simultaneously unsaturated flow, soil mechanics and reactive transport in porous media. The changes in porosity, permeability due to mineral dissolution/precipitation and irrigation time affect the hydro-mechanical behavior of the heap leach pad. The stability and the ore recovery efficiency can be predicted with more accuracy because the variable saturation and the mechanical deformation are considered during the construction and operation process.