Rheology and Hydrodynamics of Iron Ore Mineral Pulps during a Bioleaching Process in a Continuous Stirred-Tank Reactor

The rheological response and the computational hydrodynamic continuous stirred-tank behavior were analyzed to increase the understanding of the bioleaching process in mineral pulps. The rheological properties of the mineral pulps showed that a smaller particle size increases the magnitude of the rheological parameters, shortens the bioleaching process time, and, indirectly, increases the concentration of bacteria in the medium, thus augmenting the gel strength. The bioreactor hydrodynamics results revealed that the best dual-impeller configuration corresponds to a Rushton (top)/Maxflo (bottom) configuration, generating power savings of similar to 9 %. Finally, when analyzing apparent viscosity maps, velocity fields, and streamlines at different stirring speeds, enhanced hydrodynamic conditions were observed at 400 rpm.