Abstract: Carbothermic process for reducing iron ore in an externally heated vertical retort characterized in that the charging mixture is pre-heated while descent within a first zone of the retort and with a substantially constant thermal charge; a second and progressive heating following the pre-heating in a second zone of the retort to initiate the carbothermic reaction and the first reduction phase of the charged mixture; the speed of descent within the second zone being progressively slower and the thermal charge being substantially constant; and a third and constant heating following the second and progressive heating in a third zone of the retort so as to complete the reduction process; the speed of descent within the third zone being substantially the same as the speed of descent in the second zone, the thermal charge being substantially constant, and maintaining the outside temperature of the second and third zones substantially constant in at least a part of the second zone and in all of the third zone, while

Abstract: A carbothermic process and apparatus for converting iron ore directly to sponge iron in a vertical retort is described.

Abstract: Means for withdrawing sponge iron from externally heated retorts whereby the sponge iron is withdrawn at the bottom of the retort including staggered inlet and outlet means and a minimum of three worm screw means moving at the same speed but in differing directions moving the sponge iron from the inlet to outlet means. The withdrawal means provides uniform descent of the sponge iron within the retort.