Organic binders for iron ore pelletization and steelmaking

Historically, bentonite has been used in the agglomeration process in North American iron ore plants. In 1986, Eveleth Mines replaced bentonite with Peridur, a carboxy methyl cellulose organic binder used in conjunction with 1% limestone. Since May of 1993, Allied Colloids` Alcotac FE8 has been used by Eveleth as the replacement for bentonite. This paper discusses the performance benefits obtained when bentonite was replaced with an organic binder. These totally synthetic binders are used in conjunction with limestone. The benefits of organic binders are: improved metallurgical parameters of the fired pellet, especially the reducibility, which results in more efficient use of gases in the blast furnace; reduced silica in the pellet, in the case of Eveleth Mines this was a reduction of 0.5%, a lower silica pellet reduces slag in the blast furnace; increased production in both the agglomeration/induration and steelmaking processes; and a decrease in coke consumption.