Compartment mill

Many different pulverizers are used by the industry. For sand-sized particles, hammer, cage, and rod mills are utilized for soft stone, roUer mills are preferred for dust and very fine sizes, ball, tube, pebble, rod, and compartmented mills are used. 

Wet-Process Cement Ball, tube, and compartment mills of essentially the same construction as for the dry process are used for grinding. Water or clay shp is added at the reed end of the initial grinder, together with the roughly proportioned amounts of limestone and other components. 

Finisli-Grinding of Cement Clinker Typically the hot clinker is first cooled and then ground in a compartment mill in closed circuit with an air classifier. To crush the chukers, balls as large as 5 in may be needed in the first compartment. A roll press added before the ball mill can reduce clinkers to a fine size, ana thus reduce the load on the ball mills. The main reasons for adding a roll press has been to increase capacity of the plant, and lower cost. 

Tumbling mills (a) trunnion overflow mill, (b) compartment mill, and (c) conical mill. 

Rod mills can produce 5-200 ton/h of maferial reduced up to abouf 1 mm sizes, while ball mills can give 1-50 fon/h of fine powder with 70-90% sizes in the range of 70 pm. The fofal energy requiremenf for a fypical rod mill grinding differenf hard materials is abouf 5 hp h/fon, whereas for a ball mill, it is approximately 20 hp h/ton. Tube mills and compartment mills normally need somewhat more power than these figures. As the product becomes finer, the capacity of a given mill diminishes and fhe energy requirement increases. 

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