1. Steel production processes

Steel production processes from the late 19th century to the present day can be divided into 3 main types:

• Martin furnaces (also known as Siemens furnaces in Germany or Open Hearth furnaces – OH – in the United States); these furnaces produce steel from scrap and cast iron, with melting energy supplied by burners and the oxidation of impurities in the cast iron, initially with air and later with oxygen;

• electric arc furnaces, which originally produced steel by melting scrap under the effect of an electric arc. Since the 1990s, cast iron has also been fed into these furnaces, with impurities being removed using pure oxygen;

• air- or oxygen-blast converters.

The evolution of the shares of the various steelmaking processes in steel production...