Exploring effects of hydrodynamic flotation variables on their respective metallurgical responses through laboratory scaling up

Abstract: To meet the increasing demand for raw materials, higher throughput of mineral separation through froth flotation is becoming important. This higher throughput can be achieved by increasing the size of flotation equipment termed scaling up. Flotation performance is greatly affected by the size of flotation machines and remains an important research area to correlate flotation behavior between small and larger flotation machines. The Outotec GTK LabCell®, a mechanical flotation machine, has been used as a benchmark for many industrial pre-feasibility studies around the world for the past decade. This study deals with the scale-up assessment in terms of flotation rate constant between 2 L and 7.5 L flotation cells of the Outotec GTK LabCell®, machine. The design of these lab scale flotation machines is comparable to other Outotec industrial scale flotation equipment considering rotor and impeller design, and the main difference is in scale. The influence of the hydrodynamic parameters on the flotation performance in both the cells was investigated by varying the impeller tip speed and superficial gas velocity. Particle size distribution analysis indicated concentrate product was finer at smaller cell size at all combinations of impeller tip speed and superficial gas velocity. The results showed for both cells, mass and water recovery increased with an increase in the impeller tip speed and superficial gas velocity until a certain value, after which they decreased. Maximum mass and water recovery were achieved using an impeller tip speed of 3.1 m/s and superficial gas velocity of 0.21 cm/s. Flotation kinetic analysis indicated scaling up of flotation cells was possible at different impeller tip speed by keeping the superficial gas velocity at 0.21 cm/s.