BigPatents India

The invention relates to a method for the indirect reduction of particulate oxide-containing ores, especially iron oxide containing material, in a fluidized bed method at a pressure <5 bar. According to the inventive method, the ore is heated up in a fluidized bed reactor (1) that is configured as a pre-heating stage (5) using a reducing gas produced from coal. Optionally, the ore is also pre-reduced and is then reduced to sponge iron in at least one fluidized bed reactor (2,3) that is configured as a reduction stage (7,8). The reducing gas is guided via a reducing gas feed (12) or reducing gas pipe (13) in a counter-current to the material to be reduced which is guided from stage to stage from the reduction stage (7,8) to the pre-heating stage (5). After purification the reducing gas is removed as export gas. Heat is supplied to the reduction stage (7, 8) and/or pre-heating stage (5) by combustion of a part of the reducing gas provided for the indirect reduction in the reduction stage (7,8) and/or in the pre-heating stage (5) together with oxygen and/or air. Drawing: 7 Sheets Total Pages: 20 Fig. 1