Patent ID: 8377168

Claim:
A method for producing direct reduced iron (DRI) through the reduction of iron-oxides-containing particles to metallic iron-containing particles in a reduction reactor, comprising a reduction zone and a lower cooling discharge zone, by contacting said iron-oxides-containing particles with a high temperature reducing gas stream, comprising hydrogen and carbon monoxide in said reduction zone, and wherein the reduced particles now from said reduction zone down through said lower discharge zone; said method being characterized by the improvement comprising introducing into and circulating a methane-containing process gas in the form of coke oven gas containing benzene, toluene and xylene (BTX), tars and other contaminants through said lower zone including through the bed of direct reduced iron therein; withdrawing from the reactor at least a portion of the gas flowing in said lower zone; transferring externally of said reactor at least a first portion of such gas withdrawn from said lower zone; combining such first portion of said withdrawn gas with an at least partially regenerated reducing gas effluent being recycled back to the reduction zone; feeding such combined gases together into the reduction zone of said reactor; and controlling the flow rate of said methane-containing process gas so as to be greater than the flow rate of said transferred portion of said withdrawn gas by between about 50 normal cubic meters and about 300 normal cubic meters per metric ton of direct reduced iron produced in said reduction reactor.