Scale-up and modeling of flotation columns using surface areas

This research presents three models of froth flotation that recognize flotation as an interfacial phenomenon wherein the rate of solids-surface-area removal is related to the bubble-surfacearea flux. These models use two "streams", air and liquid, within the vessel. The solids within the column are associated with one, or both, of these streams. The procedures and benefits of batch tests for flotation columns are also outlined. The first model uses this batch data and the simplex method of non-linear regression to determine four model parameters: a kinetic rate constant, maximum recovery, entrainment and carrying capacity. These parameters are then used in the second model in order to estimate continuous column performance. Within the continuous model, carrying capacity is determined by overflow bubble size; recovery within the froth zone is determined by loss of bubble surface area; and solids transfer from liquid- to gas-phase is estimated by kinetic relationships and the axial dispersion model. The prediction performance of the model is verified using both batch mechanical cell and column flotation cell batch data. The final model "framework" characterizes the effect of bubble residence time and bubble loading rates within a flotation cell using mechanistic bubble - particle collision and attachment relationships.Applied Science, Faculty ofMining Engineering, Keevil Institute ofGraduat