Page 365 - Chemical Process Equipment - Selection and Design

Cake
Piston
G ilquld Feed funnel
drawoff
Wash pipe
Accessdoor
discharge Spray nozzle
Solids discharge
(a)
arge
(C)

Mechanism for
DRIVING MECHANISM

discharge
_ _ _

I
B 1

Figure 11.13. Filtering centrifuges. (a) Top suspended batch centrifugal filter; the cake is scraped off the screen intermittently at lowered
rotation speeds of 50 rpm or so, cake thicknesses of 2-6 in., cycle time per load 2-3 min (McCabe and Smith, Unit Operations of Chemical
Engineering, McGraw-Hill, New York, 1956). (b) A solid bowl centrifugal filter with continuous helical screw discharge of the cake (Bird
Machine Co.). (c) Pusher type of centrifuge in which the cake is discharged with a reciprocating pusher mechanism that operates while the
machine is at full speed (Baker-Perkins Co.). (d) Horizontal centrifugal with automatic controls for shutting off the feed, washing the cake
and scraping it off, all without slowing down the rotation (Baker-Perkin Co.). (e) Supercentrifuge for removing small contents of solids from
liquids; dimensions 3-6 in. by 5 ft, speed 1000 rps, acceleration 50,000 g, 50-500 gal/hr, cleaned after shutdown. (f) Pattern of flow in a
hydrocyclone. (9) The shape of hydrocyclone adapted to the kind of service. (h) Centrifugal action of a cyclone assisted by a high speed
impeller (Voight Gmbh).
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