Simulation of ore heap leaching using deterministic models

Abstract Leaching copper and precious metals from fragmented ore in heaps, mine stripping waste dumps, and caved workings is rapidly expanding in the western United States, and its economic value now exceeds that of underground metal mining in this region. Some of the more important kinetic and transport phenomena involved in these processes are reviewed, including chemical diffusion in solution-filled ore fragment (rock) pores and air convection in heaps. Although mathematical modeling can provide important insights, for example, explaining why Carlin-type gold ores are leached in a few weeks while years are required to leach sulfide copper dumps, simulation has generally not been used by the mining industry in forecasting metal production or making investment feasibility decisions. Many model variables are not adequately known. This review paper emphasizes underlying simulation principles and their practical limitations. A broad perspective of simulation in heap leaching is taken, rather than focusing exclusively on a particular model.