Zero CO2 steelmaking in a future low carbon economy. 1. Energy conservation in smelting hematite ore directly to refined iron slab

Abstract

ABSTRACTThe emphasis is on energy conservation. Efficient charge preheating by heat recovery from not only the molten reduction slag but even more important is to eliminate water cooling in the continuous casting of the molten iron, which overflows automatically from the primary melt circulation loop. It is proposed that a liquid metal coolant is used to capture the latent heat of solidification and also the sensible heat associated with cooling the near net shape cast refined iron slab from the melting point down to say 1000°C or so by counter-current radiative heat transfer to secure 800°C charge preheating. The preheated crushed hematite ore plus flux is distributed along the full length of the electrical conductively heated charge incorporation zone of the principal melt circulation loop at a multiple number of locations. The resulting wustite containing thin melt layer floating on the circulating molten iron is counter-currently reduced by hydrogen at atmospheric pressure.