The method by which the first iron workers in ancient time produced a sponge and incoherent mass by reduction the iron ore with the hot coals of their small bonfires has already been described. Because of its appearance, and with the passing of time, man came to call it sponge iron. This production contained metallic iron, ferrous oxide which had hot been reduced, slag and impurities and only traces of carbon. Later through beating and reheating successively, it lost a good part of the impurities and slag and turned into iron that was stronger and more useful for the making of weapons and utensils. In this way, sponge iron was the principal source of supply for iron and steel for many centuries, until, around the year 1300 A.D., a process was developed whose impact and importance to civilization are well known and which was called a Blast Furnace.
Today direct reduced iron (sponge iron) which produced by reduction of iron ore by reducing gases (hydrogen and carbon monoxide) can be used by electric arc furnace (EAF) steelmakers as a part of their metallic charge, along with normal mill returns and, if required, with certain amounts of non – selected cheap scrap. The many advantages associated with the use of sponge iron enable the EFA steelmaker to economically produce not only tight specifications steels, but also the tonnage plain carbon steels.
Direct Reduced Iron, with its sponge – like structure, is chemically active and easily oxidized. The author has developed an efficient process for the treatment of sponge iron, known as the Waxing Process, which makes the sponge iron resistant to both oxidation and corrosion and no heat generated which causes fire.
A severe test is carried on by transferring about 22 tons waxed sponge iron from Saudi Arabia to Baghdad (1300 Km) in open trucks and under slightly raining. The results showed that (1) no loss in metallization (2) no fines created (3) no heat generated.