The Impact of Hot Metal Temperature on CO2 Emissions from BOF Steelmaking
Recycled steel is a key material for sustainable development. However, not all steel demand can be met by recycling, and therefore new metallic iron must be introduced in the global cycle. The transformation of iron oxides into steel requires carbon which is oxidized into CO2. This paper focuses on the basic oxygen furnace (BOF) where molten iron is transformed into liquid steel. The process is modelled using mass and energy balances in order to assess the effect of molten iron temperature on CO2 emissions. Model results show that, for a typical converter charge, a slight change of 10 °C in the hot metal temperature can led to a direct variation of 0.01 t of CO2 per ton of liquid steel. Finally, different actuation levers for carbon mitigation are suggested. It can be concluded that operation and modelling improvements should be jointly addressed to exploit their full potential for carbon footprint reduction.