Recent status of fluidized bed technologies for producing iron input materials for steelmaking

摘要

Today steel is produced by two steelmaking processes, the basic oxygen furnace and the electric arc furnace. Three types of iron input materials for both processes are liquid hot metal or in solidified form as pig iron, direct reduced iron （DRI） and hot briquetted iron （HBI） as well as steel scrap. Hot metal, pig iron, DRI and HBI are virgin iron materials, which have to be produced from iron ore by the so-called ironmaking technologies. New ironmaking processes based on fluidized bed technology have been developed in the last two decades. The main advantage of these technologies is that fine ore can be directly used in the processes and prior treatment such as sintering or pelletizing can be avoided which is required for the established processes. Theoretical aspects for reduction of fine iron oxides in a fluidized bed reactor system will be explained. The fluidized bed reducing technologies utilized in the most advanced new ironmaking processes for direct use of fine ore, FINMET  , Circored  , FINEX  and HIsmelt  will be compared.