VERFAHREN UND VORRICHTUNG ZUR REDUKTION VON ERZEN ZU SCHWAMMETALLEN MIT EINEM GAS

摘要

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).