Pebble Grinding Mills

A pebble mill or tube mills are similar to ball mills except that the grinding media is ore. They use a form of autogenous milling but the type and size of ore are chosen more carefully than with conventional AG milling. Pebble mills typically have very long lengths compared to their diameters. They have lower power consumption and lower capacity (for a given shell size) compared to ball mills since the weight of pebbles per unit volume is lower than steel balls.

Pebble mills are useful where iron contamination from grinding media must be avoided. Special nonmetallic shell lining can also be used to further prevent contamination. Pebble mills also have reduced operating costs because of the less expensive grinding media.

- Metso Minerals images.