Page 382 - Chemical Process Equipment - Selection and Design

Producf oullef
ffo exhaust fon)

Deflector vane,

Screens

Oust colleciors.

Figure 12.4. Closed-circuit grinding processes, in which coarse products are captured and recirculated until they are brought down to size. (a)
Ring-roller mill (Raymond) with built-in air classification; crushing action is by rotating vertical rolls acting on a revolving bowl ring. (b)
Flowsketch of closed-circuit grinding with three stages of grinding and two of classifying (McCube and Smith, Unit Operations, McGruw-Hill,
New York, 1976). (c) A two-pair high roller mill (Schutz-O’Neil Co.); recycle is reground in the lower rolls; Table 12.5(c) lists materials
ground by this equipment. (d) A Hardinge conical ball mill in a closed circuit with an air classifier and dust collectors (Hurdinge Co.).

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