Abstract: The furnace is circular in plan and comprises an annular charge space charged through chutes in its top wall. Effluent gas offtakes are provided in the furnace outer wall and the level of the charge bed is maintained above the chute bottoms but below those offtakes. Hot gases generated externally of the furnace pass into it through an opening in its bottom wall or hearth and travel upwardly through the charge. Solids are discharged downwardly through the same opening in counterflow. A vertical axle is journalled centrally in an upper wall of the annular furnace chamber spaced above the opening in the hearth, and a plow affixed to the lower end of the axle rotates in an open space between the hearth of the annular furnace chamber and its inside wall, so scraping heated charge solids into the discharge opening. The axle is pressure sealed to the wall through which it passes, and that seal is the only rotating seal required for the furnace.

Abstract: A process for the simultaneous production of metallized ores and a char. A carbonaceous material such as coal is mixed on a weight ratio basis of about 1/2 coal to about 1 iron ore to about 11/2 or more coal to about 1 iron ore. The coal is mixed on a weight ratio basis with the iron ore within the ratios defined above and the mixture subjected to a heat treatment of between 1800.degree. F. to about 2200.degree. F. within a substantially air tight enclosure wherein in oxidizing atmosphere is provided in the upper portion of the enclosure and a reducing atmosphere is maintained about the materials on the floor of the enclosure. The floor of the enclosure comprises a travelling imperforate hearth with the speed of travel thereof variable so as to vary the residence time of the materials on the floor of the enclosure from the time of deposit of the materials on the hearth to the time of removal of the materials from the floor.

Abstract: The invention relates to a method and apparatus for the heat treatment of materials on a traveling hearth mounted on a horizontal plane and rotated on a vertical axis within a substantially air-tight enclosure. The materials on the hearth are deposited thereon in separate and distinct rows and retained in separate rows while undergoing heat treatment within the enclosure. The material in one of said rows is capable of evolving volatiles when the materials are subjected to a heat treatment and the evolved volatiles rise and are dispersed in the upper portion of the enclosure where the same will combine with an oxidant such as air and/or oxygen which is admitted into this portion of the enclosure. The mixture of evolved volatiles and oxidants such as air and/or oxygen will combust in the upper portion of the enclosure.