Grinding media wear

Grinding-media wear in phosphate ball-mill grinding systems ranges from 5 to 25 g/Mg (0.05 to 0.20 Ib/ton) ground Dall-mill huers show an average consumption of 2.5 to 100 g Mg (0.01 to 0.05 Ib/ton) ground. 

Adam, K., Natarajan, K. A. and Iwasaki, I., 1984. Grinding media wear and its effect on the flotation of sulphide minerals. International Journal of Mineral Processing, 12(1 - 3) 39 - 54 Ahlberg. E. and Broo. A. E., 1988. Proc. Inter. Symp. Electrochem. In Mineral and Metal Process. 

About twenty years ago the specific rate of grinding media wear in finishing mills (clinker grinding) was in the range of 800 to 1000 g per t of cement, whereas the corresponding figure is now only about 50 to 120g/t. 

Against this, the wear on the grinding medium is generally about 20 per cent greater, and it may be necessary to dry the product. 

PEBBLE MILL. A jacketed steel cylinder rotating on a horizontal axis and containing flint or porcelain pebbles as the grinding medium. Its operation is similar to that of a ball mill. It is used for grinding and mixing of dry chemicals, pigments, food products, and the like. Pebble mills are usually lined with alumina, buhrsione, or similar material to protect the walls from wear. 

Roller Mills Pendulum, Table, and Bowl Type. This is a group of machines commonly applied for grinding of mineral powders down to approximately 97% below 75 p.m, or even finer in some instances. The mills operate at medium speed, up to approximately 30 m/s, and can handle materials with up to Mohs hardness 5 before wear rates become prohibitive. Many different designs are available the two most commonly encountered variants are pendulum mills and the table roUer mill. 

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