GB1332531A - Shaft furnace smelting - Google Patents

Abstract

1332531 Smelting ores CENTRE DE RECHERCHES METALLURGIQUES -CENTROM VOOR RESEARCH IN DE METALLURGIE 25 June 1971 [30 June 1970 23 Sept 1970 8 Feb 1971] 29966/71 Heading C7D In a shaft furnace smelting process in which no oxygen is deliberately introduced into the furnace a hot reducing gas in introduced so that it ascends in counterflow to the burden, and the operation of the furnace is regulated by varying the temperature of the hot gas. The latter may be produced by reforming hydrocarbon fuel, and heated by heat exchange or electrically before introduction preferably through the tuyÚres, while its temperature may be controlled by addition of cooler reducing gas, or of hot or cold reducing substances together with an oxidizing agent in such amount that the reaction products contain Co, H 2 and N 2 . In a further embodiment the reducing gas is heated either by forming it into a plasma stream by arc or induction or by introducing it into a carrier plasma; the plasma torches may be located in the furnace tuyeres and the gas temperature may be controlled by adjustment of the power supply, while production of the reducing gas may be effected by directly reforming a fuel in the torches.