Classificating Properties and Separating Mechanism of the New-type Air Separator

Abstract

The effects of rotational speed of selector blades, number of selector blades, and circulating flow rate of air on classification properties and separating mechanism of a new type air separator (casing dia. 320mm) have been investigated.
The main results obtained are as follows:
(1) It is observed that selector blades of the rotor bring about a dead zone of air current in separating many particles and it is recongnized that the classification of this air separtor is carried out in the range where Allen's law holds.
(2) Cut size: over 20 (90% passing size of fine powder),
separating efficiency: 70-80% (lime stone)
60-70% (iron ore),
pressure drop: max. 320mm H₂O.
(3) The observed values, both cut size (d) and U_r/Uθ4/3, change in a good agreement with theoretical equations developed for the separating mechanism, that is
d=109U_r/Uθ^4/3 (lime stone)
d=79.5U_r/Uθ^4/3 (iron ore)
(4) An enlarged air separator (casing dia. 1800mm) similar to the experimental one shows the same separating mechanism and calssification properties better than those of other large-scale air separators.