Evaluation of Dissolved Air Flotation for the Treatment of Mineral Slimes

Abstract

<p>The recovery of BaSO₄ mineral slimes (-10 microns) from silica using dispersed and dissolved air flotation, was studied. Experiments were performed in a modified commercial batch flotation machine. The influence of flotation variables such as collector concentration, concentration of silica depressant, pH, aeration and mineral purity on flotation parameters were also examined.</p> <p>Experimental evidence suggests that dissolved air flotation results in enhanced BaSO₄ recovery over that normally achieved using dispersed air flotation for a limited range of experimental conditions. This range is characterized by poor BaSO₄ flotation conditions such as low pH or collector concentration. The flotation of BaSO₄ was found to be strongly influenced by variables which regulate the surface chemistry of the mineral, such as collector concentration, pH, silica depressant and mineral purity. It was also speculated that mechanical transfer or gangue into the froth may be a critical factor in the upgrading of barite ores.</p>