DIRECT REDUCTION PROCESS WITH IMPROVED PRODUCT QUALITY AND PROCESS GAS EFFICIENCY.

摘要

A direct reduction process producing DRI from iron oxide particles by reduction at a about 750 °C with a reducing gas mainly H2 and CO, that also includes CO2, H20, and methane, a the reduction reactor and the top gas effluent from the reduction reaction after cooling/scrubbing is split. The resulting first top gas portion with a first hydrocarbon-containing make-up gas passes through a catalytic reformer yielding an improved hot reducing gas first effluent. The second top gas portion passes through a CO2 removal unit and then with the second hydrocarbon-containing make-up gas passes through a heater yielding a hot CO2-lean recycle reducing gas second effluent. The first and second effluents are fed to the reducing zone of the reduction reactor as the reducing gas reactant. The flow rate of at least the second of the two make-up gases is regulated to control the carbon content of the DRI produced.