The largest use of lime is in steel manufacturing, where it serves as a flux to remove impurities (silica, phosphorus, and sulfur).  Lime is used in basic oxygen furnaces and electric arc furnaces, as well as in secondary refining.  High calcium and dolomitic lime used in the steel industry must meet exacting physical and chemical properties.

Quicklime is also used for further processing in steelworks, where harmful constituents as phosphorus and sulphur are captured by the lime. Specially customised mixtures are provided for particularly high-quality steel grades with extremely low sulphur content.

Lime products containing magnesium are used to help to regenerate the refractory materials in the furnaces.