Froth flotation method with counter-current separation

Claim 1

A FROTH FLOTATION METHOD FOR THE SEPARATION OF ONE CONSTITUENT FROM ANOTHER CONSTITUENT IN A COMMINUTED MIXTURE OF SAID CONSTITUENTS WHEREIN A CONSTITUENT THEREOF, WHICH IS AT THAT TIME HYDROPHOBIC, IS WITHDRAWN AS A FROTH WITH AIR, SAID METHOD COMPRISING: (A) ESTABLISHING AND MAINTAINING A DOWNWARDLY FLOWING STREAM OF AQUEOUS MEDIUM WITHIN A VERTICALLY ALIGNED, ELONGATED ZONE, SAID AQUEOUS MEDIUM BEING INTRODUCED AT AN UPPER PORTION OF SAID ZONE; (B) ESTABLISHING AND MAINTAINING AN UPWARDLY MOVING STREAM OF AIR BUBBLES ORINATING AT A LOWER PORTION OF SAID ZONE, WHEREIN THE DOWNWARD VELOCITY OF SAID AQUEOUS MEDIUM IS NOT GREATER THAN THE UPWARD VELOCITY OF SAID STREAM OF AIR BUBBLES; (C) ESTABLISHING AN AQUEOUS SLURRY OF SAID COMMINUTED MIXTURE AND AT LEAST ONE CONDITIONINGAGENT WHICH RENDERS A SELECTED SAID CONSTITUENT HYDROPHOBIC; (D) INTRODUCING SAID SLURRYINTO SAID ZONE AT A REGION IN SAID ZONE ABOVE SAID LOWER PORTION BUT BELOW SAID UPPER PORTION AT SUCH A RATE THAT THE SOLIDS CONTENT OF SAID SLURRY IS GREATER THAN THE SOLIDS CONTENT IN SAID ZONE;