GB734584A - Process for the treatment of fuel-ore mixtures - Google Patents

Abstract

734,584. Iron manufacture; agglomerating ores. DEMAG AKT.-GES. March 7, 1952 [March 8, 1951], No. 5958/52. Classes 72 and 82 (1). A two-stage smelting process for fuel-ore mixtures including fuel-ore briquettes comprises first coking, degasifying and preliminarily reducing the mixture at least partly by generation of induced electric currents within the mixture and then smelting the treated mixture in known manner. The fuel-ore mixture may consist of fine ballings from a bloomery or puddling furnace and fuels. The mixture may first be heated by another source of heat such as hot circulating gas and then further heated by induced currents, e.g. while moving downwardly through the induction heater. All or part of the ore fed to the induction heater may be pre-roasted or prereduced. The induction heating chamber may be formed as a passage in a low shaft furnace or, as shown in the Figure, it may be a downwardly-flared chamber 2 mounted on top of the low shaft furnace 1, being charged by a bell and hopper device mounted on the chamber. Low-temperature carbonization gas is removed through duct 5, condenser 6 and blower 8. Top gas from the smelting furnace is separately recovered by duct 11, cyclone 12, where it pre-heats the air blast to the shaft furnace, and blower 14. Alternatively the gases may be recovered together either from the top of the induction heating chamber or from between that chamber and the shaft furnace. Part of the burden, e.g. lime may be separately fed to the furnace without passing through the induction heater. Further, operation of the shaft furnace may be periodically interrupted while induction heating of the charge in the heating chamber is taking place.