Calcium Oxide is used in metallurgy industry with different purposes. In Steel is incorporated during iron and steel process as clinker agent, for then be able to eliminate impurities existing in metal parts. Calcium Oxide (lime) must contain of a high purity to improve its reactivity and performance.
In aluminum production it is also used as clinker agent because it is combined with the silica contained in the mineral which forms calcium silicate. Avoiding then the formation of iron silicate and decreasing its flash point.
Calcium Oxide (CaO) is used in production of, copper, zinc, lead, silver, nickel, gold, uranium, or even to segregate impurities by means of flotation of different metallic salts.
To conclude, Calcium Oxide has other utilities as corrosion protector and neutralization of acids used in the metallurgy industry.