The Impact of Froth Launders Design in an Industrial Flotation Bank Using Novel Metallurgical and Hydrodynamic Models

Abstract

In flotation cells, especially in large flotation units, froth management is a crucial variable that should be considered during the design phase or optimized to improve the performance of existing flotation circuits. This paper presents a simulation evaluation of the effect of launder design on the metallurgical performance of an industrial flotation circuit consisting of five TankCell® e630 (630 m3) cells in a Cu rougher duty. This analysis was carried out using a new industrial simulator that includes novel metallurgical and hydrodynamic models, developed from a wide database collected from many industrial concentrators. This tool is currently incorporated into HSC Chemistry® software and allows evaluating the effect of launder design on mineral froth recovery, water recovery, entrainment, and other variables. The industrial flotation circuit was evaluated under different launder design scenarios, considering an actual flotation circuit that includes TankCell® e630 cells for calibration and as a reference (baseline). Firstly, two different designs were evaluated in the full circuit: a standard launder design and a new launder technology. It was found that the new launder technology enabled improvement of the mineral recovery along the circuit, mainly for coarse particles, due to the improvement in froth mineral recovery. Next, a partial upgrade of the launder design along the circuit was analysed. Thus, the new launder technology was evaluated in the first and the last two cells of the bank. The results showed that upgrading the launders in different cells along the circuit delivered an increase in the final recovery with respect to the baseline, with a partial impact on the concentrate grade. However, these changes are less than those when evaluating the full upgrade scenario. A partial launder upgrade either in the first or last two cells of the bank showed similar final recoveries, but the latter enabled a slightly higher concentrate grade (about 1% higher) to be achieved. Finally, the evaluation of launder design using the industrial simulator made it possible to estimate its effect on variables that are not commonly obtained from plant surveys, including superficial gas rates at the froth surface level, froth recovery per particle size, collection recovery per particle size and liberation, gangue entrainment, and bubble loading grade.