Cold Bonding of Iron Ore Concentrate Pellets

Iron ore concentrate pellets are traditionally hardened at high temperatures in horizontal grates and grate-kiln furnaces. However, heat induration requires tremendous quantities of energy to produce high-quality pellets, and is consequently expensive. Cold bonding is a low-temperature alternative to heat induration. Pellets can be cold bonded using lime, cement, sponge iron powder, and organic materials such as starch and flour. Cold bonding consumes less energy than heat induration, and has found favor for bonding self-reducing pellets and for refractory ores that are difficult to heat-treat. Herein, we review the principal cold bonding methods and their fundamentals.