Pelletizing is the process of converting iron ore fines into spherical pellets through agglomeration and induration. It involves mixing the iron ore with a binder such as bentonite and water to form a pelletizing feed, which is then fed into a pelletizing machine. The machine compresses the feed into a narrow pellet size range and sends them onto a conveyor belt.
The pellets are then transferred to a furnace for firing or induration. The firing process involves heating the pellets to a high temperature of around 1250-1300°C, which causes the pellets to shrink and become hard. This also removes any moisture that may be present in the pellets. After the firing the pellets are cooled down and screened to remove any undersized or oversized pellets.
Pelletizing has several benefits, uniform sized and shaped pellets are produced that are easier to handle and transport. Pellets have a higher iron content than sintered iron ore, which makes them more valuable in the market and pelletizing produces less emissions and consumes less energy compared to sintering, making it a more environmentally friendly option.