Preamble

In blast furnace iron oxide +coke + flux are charged from top and air is injected through the tuyeres located near the hearth region.

The gases CO, CO₂,and N₂ leave the furnace through the top. Some amount of carbon in dissolved in iron. Pig iron and slag leave the bottom.

Under simplified conditions, one can derive equation to represent stoichiometry in blast furnace on a diagram. Such diagram is called RIST diagram.

Stoichiometry in blast furnace:

Following assumptions are made:

i) iron of iron ore enters in hot metal (or pig iron)

ii) Oxygen enters through air blast and oxides of iron.

iii) Carbon enters through coke.