Oxygen is injected into blast furnaces through spargers (devices used to spray gas into a system) to enrich the air. This process increases the productivity of the furnace, thereby lowering the overall cost of production.

In basic oxygen furnaces, oxygen is used for decarburization. Decarburization is a process that removes the carbon from molten metal in steel making. Iron scrap is melted in electric arc furnaces at steel mills. Oxygen decarburizes the molten steel to create thermal energy. This energy is enough to melt scrap metal in large quantities.

Electric arc furnaces have three primary uses for oxygen. Oxygen is used to run oxy-fuel burners for heating and melting scrap metal; in high-velocity lancing which is used in localized scrap melting processes, decarburization of steel and slag foaming; and used in sub-sonic injection processes for post combustion of carbon dioxide.