Antracita
Anthracite is a hard, compact variety of mineral coal that has a high luster. It has the highest carbon content, the fewest impurities, and the highest calorific content of any coal, which also includes bituminous coal and lignite.
Coque de petróleo
Petroleum coke is a porous solid material, black or dark gray with high carbon content and different levels of sulphur, depending on its quality, which is produced as a by-product of oil refining process.
Flexi coque
The flexicoke is formed during thermal cracking of the heavy residues.
Recarburador
The use of a recarburizer in the production of steel or founding becomes necessary due to the need for introducing carbon as alloy-former in the metal, in such a way that the metallic product reaches the proper characteristics.