Abstract: An apparatus for the treatment of divided solid material is provided having a chamber disposed about a generally vertical axis. Means are provided for introducing the divided solid material into the top portion of the chamber and further means are provided for introducing a pressurized gas into the bottom portion of the chamber. The apparatus includes first impeller means, supported by a first shaft adapted to rotate about the axis, and situated in the top portion of the chamber, for fluidizing the divided solid material in the top portion of the chamber to thereby prevent the divided solid material from clogging within the top portion of the chamber. Additionally, the apparatus includes second impeller means, spaced from the first impeller means, supported by a second shaft adapted to rotate about the axis, and situated in the bottom portion of the chamber, for radially dispersing the pressurized gas and for fluidizing the divided solid material in the bottom portion of the chamber.