Patent ID: 6395056
Filing Date: 2002-05-28
Classification: C21B,Y02P

Abstract:
A method for reducing iron-oxide-containing particles in the solid state by reaction of said iron oxides with a reducing gas stream at a temperature higher than about 850Â° C., said method comprising:feeding a particulate material containing iron oxides to a preheating device; heating said particulate material to a temperature above about 600Â° C. with a non-reducing gas; feeding said heated particulate material to a reduction chamber; introducing to said reduction chamber wherein said iron oxides are, at least partially, chemically reduced to metallic iron; introducing a first stream of a reducing gas comprising hydrogen, carbon monoxide and methane into said chamber at a temperature above about 850Â° C. to effect the reduction of said particulate material; withdrawing a second stream of reducing gas from said reduction chamber; cooling at least a portion of said second stream of reducing gas; removing water from at least a portion of said second stream of reducing gas; recycling and pressuring at least a portion of said cooled gas forming a third stream; reforming at least a portion of said third stream by means of a gas reformer, forming a fourth stream mainly comprising hydrogen and carbon monoxide as its main constituents; combining an oxygen-containing gas to said fourth stream forming said first stream; introducing said first stream to said reduction chamber; and, removing the metallic iron from said reduction chamber.