Abstract: A conveyor (10) for transporting powder from an inlet point (14) to at least one discharge point (20) comprises a fluidized bed transport space (12) and a fluidization gas supply space (16), the fluidized bed transport space (12) being separated from the fluidization gas supply space (16) by a gas permeable wall (18); a gas outlet (22) for removing fluidization gas from the transport duct (12); means (24) for separating dust from the removed fluidization gas; and means (26) for returning the separated dust to the powder proximate the discharge point (20). In a preferred embodiment, the separated fines dust is returned to, and homogenized into, the powder in a lower portion of a cyclone, which is located at the discharge point.

Abstract: An aluminum production electrolytic cell (14) comprises a bath (20) with bath contents (18), at least one cathode electrode (22) in contact with said contents (18), at least one anode electrode (16) in contact with said contents (18), and a hood (36), defining interior area (36a), covering at least a portion of said bath (20). The electrolytic cell (14) is equipped for effluent gases to be drawn from said interior area (36a). The electrolytic cell (14) also comprises at least one heat exchanger (74) for cooling at least a portion of the gases drawn from interior area (36a), prior to circulation thereof to interior area (36a) through at least one distribution device (90).

Abstract: A conveyor (10) for transporting powder from an inlet point (14) to at least one discharge point (20) comprises a fluidized bed transport space (12) and a fluidization gas supply space (16), the fluidized bed transport space (12) being separated from the fluidization gas supply space (16) by a gas permeable wall (18); a gas outlet (22) for removing fluidization gas from the transport duct (12); means (24) for separating dust from the removed fluidization gas; and means (26) for returning the separated dust to the powder proximate the discharge point (20). In a preferred embodiment, the separated fines dust is returned to, and homogenized into, the powder in a lower portion of a cyclone, which is located at the discharge point.

Abstract: A conveyor (10) for transporting powder from an inlet point (14) to at least one discharge point (20) comprises a fluidized bed transport space (12) and a fluidization gas supply space (16), the fluidized bed transport space (12) being separated from the fluidization gas supply space (16) by a gas permeable wall (18); a gas outlet (22) for removing fluidization gas from the transport duct (12); means (24) for separating dust from the removed fluidization gas; and means (26) for returning the separated dust to the powder proximate the discharge point (20). In a preferred embodiment, the separated fines dust is returned to, and homogenized into, the powder in a lower portion of a cyclone, which is located at the discharge point.

Abstract: An aluminium production electrolytic cell (14) comprises a bath (20) with bath contents (18), at least one cathode electrode (22) in contact with said contents (18), at least one anode electrode (16) in contact with said contents (18), and a hood (36), defining interior area (36a), covering at least a portion of said bath (20). The electrolytic cell (14) is equipped for effluent gases to be drawn from said interior area (36a). The electrolytic cell (14) also comprises at least one heat exchanger (74) for cooling at least a portion of the gases drawn from interior area (36a), prior to circulation thereof to interior area (36a) through at least one distribution device (90).

Abstract: A conveyor (10) for transporting powder from an inlet point (14) to at least one discharge point (20) comprises a fluidized bed transport space (12) and a fluidization gas supply space (16), the fluidized bed transport space (12) being separated from the fluidization gas supply space (16) by a gas permeable wall (18); a gas outlet (22) for removing fluidization gas from the transport duct (12); means (24) for separating dust from the removed fluidization gas; and means (26) for returning the separated dust to the powder proximate the discharge point (20). In a preferred embodiment, the separated fines dust is returned to, and homogenized into, the powder in a lower portion of a cyclone, which is located at the discharge point.

Abstract: Methods and apparatus are provided, which separate out at least a portion of fine dust, including fluoride, from recycled alumina. The difference in natural drop velocity and flow properties of fine and coarse particles is used to effect the separation.