A wet classification process for a high-grade powder and for the use of low-grade resources has been investigated. The boundary size at which the particles are precipitated or not in a centrifugal separator was analyzed. As a result, classificating of the particles below 325 mesh could be performed. Thus, the separation size D(μm) expressed by Stokes diameter could be reprensented by;
D2=3382·Q·r-3·n-2
using the flow rate Q(m3/h), the radius r(m), and the rotation speed n(rpm) of the rotary vessel.
