Abstract: A method is disclosed for the gaseous reduction of iron ore to sponge iron at a given degree of carburization and yet at a temperature suitable for hot briquetting or for direct feed to a melter or to a refining furnace. The desired percentage of carburization and the preferred elevated temperature are achieved by using a hot blend of recycled reducing gas and essentially uncracked natural gas or methane to carburize and to decrease the temperature of the sponge iron in the modifying zone of the reactor.

Abstract: A method is disclosed for the gaseous reduction of iron ore to sponge iron at a given degree of carburization and yet at a temperature suitable for hot briquetting or for direct feed to a melter or to a refining furnace. The desired percentage of carburization and the preferred elevated temperature are achieved by using a hot blend of recycled reducing gas and essentially uncracked natural gas or methane to carburize and to decrease the temperature of the sponge iron in the cooling zone of the reactor.

Abstract: A method is disclosed for achieving improved reduction efficiency and economy in the reduction of particulate metal ores, e.g. iron ore, in a vertical shaft, moving bed reactor having a reduction zone in which a heated reducing gas is caused to flow through a portion of the ore bed to reduce the metal ore thereof to metal; e.g. sponge iron. The improved efficiency and economy is achieved through an integrated reduction system in which a conventional reformer is used without the need to upgrade the reformed gas prior to feeding it directly to the reduction reactor as a reducing gas.

Abstract: Process and apparatus for the gaseous direct reduction of iron ores wherein at least a portion of the spent reducing gas effluent from a reduction reactor is upgraded and thereafter heated and recycled to said reactor forming a reducing gas loop and make-up reducing gas is added to said loop. The hot products of combustion, i.e., flue gases, in the reformer are used to heat the recycled gas (and optionally the quenched make-up gas) while maintaining independent control of the operating conditions of the reformer and gas heater to give improved thermal efficiency and fuel savings. The reformer has a stand-by stack through which the reformer flue gas is directed when the gas heater is shut down (to permit independent continuous operation of the reformer).

Abstract: Process and apparatus for the gaseous direct reduction of iron ores wherein at least a portion of the spent reducing gas effluent from a reduction reactor is upgraded and thereafter heated and recycled to said reactor forming a reducing gas loop and make-up reducing gas is added to said loop. The hot products of combustion, i.e., flue gases, in the reformer are used to heat the recycled gas (and optionally the quenched make-up gas) while maintaining independent control of the operating conditions of the reformer and gas heater to give improved thermal efficiency and fuel savings. The reformer has a stand-by stack through which the reformer flue gas is directed when the gas heater is shut down (to permit independent continuous operation of the reformer).