Sugar centrifuge

The rotor of a continuously operating sugar centrifuge comprises an annular array of arcuate and radially extending screws (7) each separating an inlet space, into which sugar slurry is fed from inlet 27, from a filtrate space which is divided into two zones discharging respectively into channels 71, 72. The inlet spaces also include nozzles 50 to 54 delivering wash liquid at various levels to wash the centrifuged crystals. Slides 23 are pulsated by various means to control discharge of washed and dried crystals from the outer end of each inlet space. In Fig. 1 the crystals are thrown on to a cone 61 which rotates at half the speed of the rotor, and as they fall from the cone they are slowed by a rising current of air, created by the rotation of upper rotor wall 3 and an array of fixed vanes 76. In Fig. 9 (not shown) crystals are discharged tangentially and braked by a reverse current of air. Crystal damage is thus minimised.