The Sixth Royal Society Technology Lecture - Nuclear energy for the steel industry

Abstract

The steel industry, as a major consumer of coking coal and hydrocarbons, is exploring ways to reduce its dependence on these potentially expensive raw materials by making direct use of nuclear heat. Of the present two routes for producing steel, the major one (the hot metal route) employing the blast furnace which reduces iron ore to yield molten iron which is subsequently refined by basic oxygen steelmaking, does not lend itself to the application of nuclear heat; in the second (the cold metal route) recycled steel-or a substitute-is melted in an arc furnace where already today a proportion of the electricity used is generated in nuclear power stations. The development of ‘direct reduction’ processes allows iron ore to be converted to a solid pre-reduced iron product. In the conventional prereduction process, fossil fuels are used as both fuel and as chemical reductant. With nuclear heat, the fossil fuel-re-formed to a suitable reductant-is confined to the chemical role and not used as a source of heat. This reduction stage would be followed by arc melting, as in the present cold metal route. This basic process, which at present constitutes the minor route, could become the major one for the manufacture of steel in the long term. The lecture will discuss the various processes and outline a possible configuration for an eventual nuclear steelworks, together with some of the technical problems involved.