Froth flotation method for recovery of ultra-fine constituent

摘要

A froth flotation method and apparatus for the recovery of ultra-fine constituent are provided. The apparatus includes a flotation column having a drain for withdrawing tailings and underflow and an overflow for recovering the selected ultra-fine constituent. A mechanism is provided for delivering a wash medium to an upper portion of the column as well as for delivering diffuse air to a lower portion of the column. A slurry including the constituent to be recovered is received and conditioned within a tank that is connected by means of a feed line to the column. Additionally, a mechanism is provided for dissolving air in the slurry in the conditioning tank. Further, one or two matrixes may be mounted across the flotation column to further improve recovery. The method broadly includes the steps of (1) dissolving air in the slurry in the conditioning tank; (2) feeding the slurry through the feed line into an intermediate portion of the flotation column; (3) adding a reagent to the slurry that renders the selected constituent hydrophobic; (4) establishing and maintaining a downwardly flowing stream of wash medium in the flotation column; (5) establishing and maintaining an upwardly moving stream of diffuse air originating at a lower portion of the flotation column; and (6) recovering the selected ultra-fine constituent and diffuse air from the upper portion of the column.