GB1468450A - - Google Patents

Abstract

1468450 Producing steel, steel alloy or iron from oxides. UDDEHOLMS AB 10 Sept 1974 [28 Nov 1973 3 April 1974 (2) 22 May 1974 14 June 1974] 39461/74 Heading C7D A metal oxide is reduced to metal by reaction with a reducing agent in a body of molten metal by introducing metal into a converter 1 through a melting zone spaced from the converter and having at least one channel 8 opening into the deepest region of the converter below the molten metal surface and electric induction heating means e.g. windings 12, a temperature gradient being established in the molten metal between the melting zone and the converter thereby forcing the hotter metal from the melting zone out into the deepest region of the converter, introducing the metal oxide suspended in a carrier gas into the molten metal body below its surface through at least one tuyere 14 directed towards the channnel 8 to bring about replacement of the hotter metal in the deepest region by colder metal from other parts, and removing molten metal e.g. via tap hole 15 from the converter. For producing iron or steel the oxide may be haematite and/or magnetite ore concentrate, and the molten metal may be pig iron or steel, a stoichiometric mixture of C or carbonaceous material and ore concentrate suspended in the carrier gas being injected into the molten metal body. For unalloyed steel the molten metal temperature is 1480 to 1550‹C; for producing alloyed steel, the suspension injected may include powdered magnetite, chromite, to yield e.g. 1À1% Cr, and scheelite, to yield e.g. 2À5% W. CaO may be present in the suspension for eliminating S. The C e.g. coal or coke powder may be injected through the tuyere and/or supplied on top via port 17; alternatively fuel oil or hydrogen gas may be supplied. Addititionally iron oxide pellets may be supplied from above. The carrier gas may be air, hydrocarbon gas, or argon and/or steam. Once the desired C content has been achieved, the converter atmosphere may be replaced by argon, the temperature raised by continued air blowing through the tuyere, the slag removed and the molten metal tapped for vaccuum refining.