Development of an unsteady state model for the tank bioleaching of sulphide mineral concentrates in flow reactor systems

Includes bibliographical references.In this thesis, it is hypothesized that in bioleaching flow reactor systems, high reaction rate regions exist that can be maintained by application of biological stress trajectories. Reactor models are developed for the purpose of optimising plant operation, understood here as maximising the production rate. Complicating this attempt are a) the non-linear dynamics associated with the kinetics and b) the primary reaction's being multiphase. Mathematical models are developed to establish which particle parameters are necessary to describe reactor performance using the method of segregation. The models are distinguished by the combination of either particle residence time or age and/or particle size distributions. The models evaluated at steady state are validated against pilot plant data obtained from the Fairview Mine in South Africa and were found to be in good agreement with the data. As the model was developed using a segregation approach and thus incorporates age distributions in the model formulation, the model could be extended to unsteady state operation