GB260232A - Process for the manufacture of low-carbon metals and alloys - Google Patents

Abstract

260,232. Nilson, G. E. R. Oct. 22, 1925, [Convention date]. Extracting.-In a process for the production of low-carbon iron of the kind in which molten ore is reduced by means of a high-silicon alloy, the manufacture of the high silicon alloy is carried out in two steps, (1) producing a relatively high carbon alloy by the reduction, in the presence of suitable fluxes, of a silicate slag, rich in metal oxides, obtained as a by-proluct m the manufacture, by the silico-thermic process, of a low carbon or metal alloy, and (2) melting this alloy with carbon and silica to obtain a high silicon alloy containing not less than 15 per cent of silicon, this reducing alloy being added while in the molten condition to the previously melted ore. For example, in the production of low carbon ferro-manganese, a charge of slag rich in manganese, obtained in the silico-thermic reduction of a manganese ore, is smelted with coke in an electric furnace to produce ferro-manganese rich in carbon and poor in silicon. This ferromanganese is then reduced with silica and coke, and, in the molten condition, is added to a melted charge of manganese ore, coke and quicklime. To facilitate reduction, aluminium silicate with additional carbon may be added to the charge in the formation of the high silicon alloy. The ore may be reduced by means of carbon to the lowest form of oxide before adding the silicon alloy.