Two significant stages in iron production:
1 to chemically change the mined ore e.g.
4 FeCO3 + O2 > 2 Fe2O3 + 4 CO2
This effectively enriches the ore.
2 To cause micro-cracking in the ore particles
to facilitate gas penetration during smelting
To reduce the metal compound (oxide) to metal using carbon monoxide as the reducing
Fe2O3 + 3 CO > 2Fe + 3 CO2
To generate a low melting point slag from the gangue compounds in the ore with contributions
from the fuel ash and lining.
2 FeO + SiO2 > 2 FeO.SiO2 (fayalite M.Pt 1177oC)