Semiautogeneous mill

Thus, in a typical copper extraction process the rocks are reduced to very fine particles through verttmiUs, semiautogeneous mills, and ball mills. Further separation occurs through flotation circuits and grinding. 

Wet comminution generally reduces 25 mm (1 in) particles down to very fine sizes by grinding and attrition in slurry form. This process involves semiautogenous mills, autogenous imlls, ball mills, hydrocyclones, columns, etc. 

The feed to a grinding mill must be crushed to a size appropriate to the grinding process. Semiautogenous mills require httle crushing ball mills require a finer crushing. 

In the last 20 years, the mining industry has tended to replace rod mills with large autogenous and semiautogenous mills... 

Used for autogneous and semiautogeneous milling in dosed drcuit... 

Jaw crusher feed diameter 0.1 to 1.5 m reduction ratio 5 1 to 10 1 capacity 1 to 300 kg/s Mohs hardness <9 (reduction by compression). Gyratory crusher feed diameter 0.75 to 1.5 m reduction ratio 5 1 to 10 1, usually 8 1 capacity 140 to 1,000 kg/s Mohs hardness <9. More suitable for slabby feeds than jaw crusher (reduction by compression). Roll crusher feed diameter 1 cm reduction ratio 5 1 to 10 1 capacity 0.3 to 20 kg/s Mohs hardness <7.5. Suitable for softer, friable, and nonabrasive materials. OK for wet and sticky materials. Cone crusher and short head cone feed diameter <25 cm reduction ratio 5 1 to 10 1, usually 7 1 capacity 5 to 300 kg/s Mohs hardness <8. Usually secondary or tertiary crusher. Impact crusher pulverizers, shredders, or smooth roll feed diameter 1 cm with a reduction ratio of 7 1 to 10 1 capacity 0.3 to 50 kg/s. Mills, hammer, feed diameter 10 mm, reduction ratio 10 1 to 50 1, capacity 0.01 to 5 kg/s Mohs hardness <4.5. Maximum fines feed not hard or abrasive. Mills, ball, and rod feed diameter 0.5 mm with a reduction ratio of 10 1 to 50 1 Mohs hardness <9. Mills, autogenous, semiautogenous feed diameter 200 mm, reduction ratio 10 1 to 50 1 capacity 0.1 to 100 kg/s Mohs hardness <6. Mills, fluid energy feed diameter 50 pm reduction ratio 10 1 to 50 1 capacity <2 kg/s Mohs hardness <4.5. 

Some materials exhibit a change of packing abilities and therefore density as a function of particle size. If the solids are to be passed through a comminution process, a SAG (semiautogeneous), or ball mill, they can occupy more volume per unit mass as they be-... 

Autogenous and semiautogenous (AG and SAG) mills are extremely large mills with a maximum diameter of 12.2 m (40 ft). In the last few years, Siemens and ABB have devel-... 

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