Abstract: A method for the separation of components of a slurry by froth flotation are provided. The apparatus includes a flotation column having a slurry feed for introducing slurry into the flotation column, a bubble generator for generating bubbles of gas at the bottom of the flotation column and a froth overflow at the top of the flotation column for collecting and discharging a froth fraction of the slurry. The central portion of the flotation column includes a plurality of vertically-spaced tail ports disposed alternately on opposite sides of the flotation column for discharging a non-float fraction of the slurry. In addition, a single, fluid-impermeable baffle having at least two edges is associated with each tail port. The baffles are of sufficient size to block the vertical flow in at least 50% of the horizontal cross-sectional area of the flotation column to thereby create a quiescent flow zone in the area of each tail port, wherefrom the non-florable fraction of the slurry is removed.

Abstract: An improved method for recovering lead sulfides from a mineral deposits. Pulverized mineral deposit material is mixed with water, agitated with pH adjustment from about 8 to about 10.5 to form a slurry. Rapeseed oil is added to the conditioned slurry to render the surface of the lead sulfide particles hydrophobic. After agitating and adding a frothing agent, air bubbles are injected into the resultant composition to cause hydrophobic lead sulfide particles to become attached to the air bubbles and to rise and form a froth fraction which is then separated and recovered. The process uses substantially non-toxic rapeseed oil as a hydrophilizing agent. The process is less environmentally damaging, less costly and more specific in separating lead sulfides from iron containing minerals which are normally present in ores together with the lead sulfides.

Abstract: Apparatus and method for the separation of components of a slurry by froth flotation are provided. The apparatus includes a flotation column having a slurry feed for introducing slurry into the flotation column, a bubble generator for generating bubbles of gas at the bottom of the flotation column and a froth overflow at the top of the flotation column for collecting and discharging a froth fraction of the slurry. The central portion of the flotation column includes a plurality of vertically-spaced tail ports disposed alternately on opposite sides of the flotation column for discharging a non-float fraction of the slurry. In addition, a single, fluid-impermeable baffle having at least two edges is associated with each tail port. The baffles are of sufficient size to block the vertical flow in at least 50% of the horizontal cross-sectional area of the flotation column to thereby create a quiescent flow zone in the area of each tail port, wherefrom the non-flotable fraction of the slurry is removed.