Abstract: Method and apparatus for cooling hot reduced material output from a reduction furnace without exposing the material to oxygen in the air. A fluid-bed-cooler which receives the heated, reduced, material from the reduction furnace contains cooling pipes through which a cooling liquid is passed for indirectly cooling the reduced material. Additionally, the cooler is connected to a positive pressure reduction gas recirculating distribution system which continually passes cooled and cleaned oxygen-free reduction gases over the heated, reduced, material to be cooled. Any losses due to leaks in the recirculating reduction system, are replaced by oxygen-free reduction gas supplied from an exhaust gas port of the reduction furnace.

Abstract: A novel kiln with overlying beds arranged about a central hollow shaft carrying rabble arms attached thereto and with alternate apertures formed in the floors between adjacent stories adjacent the hollow shaft and adjacent the periphery of the floor and with treatment gases being supplied through such orifices in a direction opposite to the direction in which the material moves through a furnace and further providing hot gas feed conduits located in the walls of the furnace in one or more stories and directed in a generally tangential direction relative to the story floors.

Abstract: Method and apparatus for the thermal treatment of slurries such as slurries of magnesite hydrate or the like. The method involves suspending the slurry in an airstream, passing the airstream with the suspended slurry particles into contact with a heated gas stream in a dryer, passing the thus-dried slurry to a multi-tiered heated kiln, introducing heated gases into the kiln for drying contact with the thus dried slurry, and passing the exhaust gases from the kiln to the dryer to serve as the heated gas stream.

Abstract: The method and mechanism for thermally treating a slurry of material such as a magnesite hydrate wherein a kiln housing has an upper chamber portion and a lower chamber portion with spray nozzles in the roof of the upper chamber for directing a spray of slurry downwardly and a rotor with arms in the lower portion and separators forming a plurality of tiers in the lower portion with heated gases directed tangentially into the chamber at the base of the upper portion and additional gases directed into the lower portion with the heat treated material being drawn from the base of the chamber and evaporated moisture withdrawn from the top of the chamber, and dust separated from the moisture and reintroduced into the chamber.