Classifying and Sand Cyclones

Classifying cyclones are used for separating particles of different sizes.  The classifying cyclone is mounted vertically.  The smaller particles come out the top and the larger particles the bottom.  This equipment is also known as a sand cyclone in the quarrying industry and is suitable for classifying particles from 20 to 150 microns.

Operation

In cyclones, the small particles are separated by centrifugal and vortex action (the cyclone itself does not move).  The water/particle mixture is pumped into the side of the cyclone tangentially (1) and swirls around creating a vortex in which the smaller particles (less than 100 micron) are sucked to the middle (2) and out to a dewatering screen.  The larger particles are thrown by centrifugal force to the wall of the cyclone and are discharged at the bottom end (3).