High capacity agglomeration
The balling area is where the powdered ore is mixed with water and rolled in rotating drums to create spherical balls. The green balls are spherical agglomerates nominally 12.5 mm in diameter, formed by rolling a moist mixture of finely ground iron ore concentrate, binder and sometimes a flux. The principle bonding mechanism in the green balls is the surface tension of water which is augmented by the binder.
Metso's pelletizing drums are high capacity agglomerators in closed circuit with roller screens, can create agglomerates from 2 variety of material to a tight tolerance.
Metso's balling drum is a variable speed rotary drum. The drum is normally rubber lined. The pellets are discharged onto a roller screen where the pellets are sized. The oversize is crushed and recycled back to the raw feed. The undersized is also recycled back to the drum feed to act as seeds for the fresh feed.