Grinding / Comminution / Size Reduction

The third step in comminution/size reduction begins at the grinding stage where material from crushers is further reduced in size. Grinding or comminution (size reduction) of ore materials is necessary to unlock or liberate minerals from waste materials. Grinders utilize compression, impact, abrasion and attrition to achieve certain particle size reduction/shape necessary for further minerals processing techniques. Grinders are often categorized as coarse, fine and ultra fine, with particle size getting progressively smaller.

Materials from crushers are fed to coarse grinding mills which consist of either AG/SAG mills or rod mills. Fine and ultra fine grinding is then performed depending on the material and the level of size reduction necessary. Grinding mills such as ball mills, pebble mills, vibratory mills, high pressure grinding rolls, and stirred media mills are common.

- FLSmidth Minerals, Metso Minerals, Sandvik Mining and Construction, KHD Humboldt Wedag, Nippon Eirich Co. images.