Amine Flotation of Rougher Concentrate and Intermediate Pebble in a Column Cell
Pilot plant studies were carried out in a 2 TPH Dual Extraction Column (DEC) at five operating mines to determine the efficacy of column cells in amine flotation rougher phosphate concentrate and intermediate pebble (IP) product. The DEC unit employed in the study had a diameter of 0.6 m with an overall height of 0.9 m. The study showed that the column was effective in processing fine and coarse rougher concentrates. The column capacity was determined to be approximately 3 TPH and 4 TPH for fine and coarse rougher concentrates, respectively. The optimum amine dosages for better or comparable separation results were determined to be approximately 40-60% of those currently employed in plant operations. The study showed that the use of columns will result in considerable savings in reagent costs and overall plant operating and maintenance costs. The column was successful in processing rougher concentrate feed having insol of 40% or higher and the use of process water had minimal effect on the performance of the column cell.
For IP upgrading, the use of amine provided by Arr-Maz was effective in producing a concentrate of sufficient purity that can be blended with the pebble. The study showed that with amine dosages of 0.5-1 lb/T, the IP can be upgraded from 40-45 BPL and insol of 38-45% to give a concentrate containing 58-62 BPL and insol of 16-18% with the product grade being limited by liberation issues. Owing to the inefficiency of the IP screens, they may be replaced by column cells.