Fine pyrite flotation in an agitated column cell

The flotation of fine pyrite has been studied in a 0.1 m×1.9 m agitated column. The variables studied were agitation, air and slurry feed rates. The recovery and selectivity were determined for various size fractions as a function of the column operating variables. The results obtained indicate that particles less than 25 μm may be selectively recovered provided the agitation rates are kept below 400 rpm. Increasing the airflow rate at a fixed agitation rate of 400 rpm resulted in a decrease in the selectivity. The loss of selectivity at higher agitation and airflow rates is attributed to the increased entrainment of fine gangue particles. The results obtained suggest that maximum external power input of about 0.3 kW/m 3 is required for separation of the fine pyrite.