System and method for producing metallic iron

A method of reducing iron ore and other iron oxide sources comprising:

• providing a furnace housing having a drying/preheat zone capable of providing a drying/preheat atmosphere for reducible material, a conversion zone capable of providing a reducing atmosphere for reducible material, a fusion zone capable of providing an atmosphere to at least partially reduce metallic iron material, and a cooling zone capable of providing a cooling atmosphere for reduced material containing metallic iron material, the conversion zone being positioned between the drying/preheat zone and the fusion zone,
• providing a hearth capable of being movable within the furnace housing in a direction through the drying/preheat zone, then the conversion zone, then the fusion zone, and then the cooling zone,
• positioning a hood within at least a portion of the conversion zone, fusion zone or both separating the atmosphere of the conversion and fusion zones where the hood is positioned into an upper region and a lower region, with the lower region adjacent the hearth and the upper region adjacent the lower region and spaced from the hearth,
• moving the hearth containing iron oxide bearing material and carbonaceous material in the furnace housing through the drying/preheat zone to dry and preheat the iron oxide bearing material and carbonaceous material, then through the conversion zone to heat the iron oxide bearing material and carbonaceous material to about 2350° F. (1287° C.) to at least partially reduce the iron oxide bearing material,
• injecting a gaseous reductant into the lower region adjacent the hearth at a point where the temperature proximate the hearth is about 2450° F. (1343° C.), and moving the hearth containing iron oxide bearing material and carbonaceous material in the furnace housing through the lower region of the fusion zone in the presence of the injected gaseous reductant to fuse the reduced iron oxide bearing material to metallic iron material, and then through the cooling zone to cool the metallic iron material.

A method of reducing iron sources comprising:

• forming a furnace housing having a drying/preheat zone capable of providing a drying/preheat atmosphere for reducible material, a conversion zone capable of providing a reducing atmosphere for reducible material, a fusion zone capable of providing an atmosphere to at least partially reduce iron material, and a cooling zone capable of providing a cooling atmosphere for reduced material containing iron material, the conversion zone being positioned between the drying/preheat zone and the fusion zone,
• providing a hearth capable of being movable within the furnace housing in a direction through the drying/preheat zone, then the conversion zone, then the fusion zone, and then the cooling zone,
• providing a separation barrier within at least a portion of the conversion zone, the fusion zone or both, separating the atmospheres of the furnace housing where the separation barrier is located into a combustion region and a reducing region, with the reducing region adjacent the hearth and the combustion region adjacent the reducing region and spaced from the hearth,
• injecting a gaseous reductant into the reducing region adjacent the hearth, and
• moving the hearth containing iron bearing material and carbonaceous material in the furnace housing through the drying/preheat zone to dry and preheat the iron bearing material and carbonaceous material, then through the reducing region of the conversion zone to heat the iron oxide bearing material and carbonaceous material to fluidize volatilizable material from the iron bearing material and carbonaceous material and at least partially reduce the iron oxide bearing material, then through the fusion zone to fuse the reduced iron oxide bearing material to metallic iron material, and then through the cooling zone to cool the metallic iron material,
• causing volatile material from the iron oxide bearing material and carbonaceous material in the atmosphere of the reducing region of the conversion zone to flow into the atmosphere of the combustion region of the conversion zone, and
• combusting said volatile material in the atmosphere of the combustion region of the conversion zone to at least partially heat the iron oxide bearing material and carbonaceous material in the reducing region of the conversion zone.