Evaluation of factors affecting the carrying capacity of laboratory flotation column treating copper sulfides

One of the necessary parameters in designing and scaling up flotation columns is carrying capacity (Ca) which can be determined in terms of mass of solids per unit time per unit column cross sectional area. The prediction of Ca for a given flotation technology has been commonly achieved using a simplified expression based on a representative particle size and density of the floatable material, regarding several assumptions in limited data ranges. In determining the Ca, the effect of operational parameters, such as particle size, pulp solids rate, bubble diameter, air flow rate, pulp solid content, frother dosage and froth height should be considered. In this study, the effect of these parameters on the Ca was investigated in column flotation. The studied sample was obtained from rougher circuit concentrate of Sungun copper complex flotation plant. It was found that when the pulp solid rate increased up to 1.4 cm/s, more surface of bubbles is covered by entering more solid particles to the column and Ca increased, but it decreased in higher rates. In lower speed of input pulp, the increase of frother dosage led to higher Ca, but in pulp rate higher than 1.2 cm/s, the maximum Ca was obtained in frother dosage of 45 ppm. By decreasing the froth height and increasing the solid percent up to 30%, Ca increased. Likewise, the results of the experiments with particles of different size distribution showed that the input pulp with size 44-63 μm had the maximum Ca.