Flotation column with constant feed arrangement

A method and apparatus for separating particulate material. The method includes the steps of delivering a substantially constant supply of feed to a first aerator, aerating the substantially constant supply of feed in the first aerator, introducing the substantially constant supply of aerated feed to a flotation vessel below a froth/liquid interface within the vessel, so that floatable particulate material entrained by air bubbles from the first aerator can float upwardly to the froth/liquid interface. Air is introduced into the liquid phase in the flotation vessel via a second aerator located below the level at which the aerated feed is introduced into the flotation vessel, so that floatable particulate material not entrained by air bubbles from the first aerator, may be entrained by air bubbles from the second aerator, as the air bubbles from the second aerator rise upwardly through the liquid phase to the froth/liquid interface.