Since flotation is widely used to separate the values from the gangue, the particle size distribution of the particles leaving the grinding circuit is generally determined by the known capabilities of conventional Flotation Equipment. Existing flotation equipment work very well for sizes typically in the range of 50 to 150 μm. If the upper size limit for flotation could be increased, by innovations in machine design, there would be dramatic reductions in grinding energy, which would lead to savings of great consequence for the running costs of the whole operation. In his talk, the effect of the final grind size from the grinding circuit on the energy costs for a typical base metal concentrator were discussed, with reference to a simple grind/float/re-grind/float circuit.
Potential savings will arise not only from the reduction in energy costs, but also in the media costs that are of the same order. The talk finished with considerations of the way in which the flotation process could be improved, to increase the recovery of coarse particles, using new and innovative technology, such as fluidised bed flotation.
Flotation Machine has promoted a wide scope of research activities ranging from fundamental chemistry and hydrodynamic studies to studies of industrial operations. In general, fundamental studies have been mainly related to ideal situations. In recent years, however, large efforts have been focusing on achieving a better insight into the actual sub-processes provided by the development of new and more sophisticated instrumentation. Since the massive incorporation of flotation columns, around 15 years ago, a renewed interest in flotation fundamental studies, process modelling and new cell designs have been observed worldwide.