ANZIAM J. 46(E) ppC439--C457, 2005.

A two-dimensional CFD model for heap bioleaching of chalcocite

M. J. Leahy

M. R. Davidson

M. P. Schwarz
(Received 21 October 2004, revised 12 May 2005)

Abstract

A 3-phase computational fluid dynamics (CFD) model for heap bioleaching of chalcocite is investigated to identify and understand the effect of oxygen flow during air sparging. The study uses an existing one-dimensional model of liquid flow, bacterial transport (including attachment/detachment of bacteria to ore particles), and the depletion of a copper-sulphide, coupled with a two-dimensional model of gas flow in the heap. The CFD model includes the effects of oxygen and ferrous ion consumption, coupled with leaching of copper-sulphide via a shrinking core model. The model is used to investigate the two-dimensional effects of air flow in heap bioleaching with regard to oxygen limitation. Under oxygen limitation, copper leaching is found to occur from the bottom up, successively leaching the oxygenated regions and moving slowly up the heap to leach the whole bed. Some experimental validation is provided.

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Authors

M. J. Leahy
M. R. Davidson
Dept. Chemical and Biomolecular Engineering, The University of Melbourne, Melbourne, Australia. mailto:martin.leahy@csiro.au
M. P. Schwarz
Commonwealth Scientific and Industrial Research Organization, Division of Minerals, Clayton, Australia.

Published June 3, 2005. ISSN 1446-8735

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