Separator for sorting particulate material

Claim 1

A separator for sorting particulate material suspended in a conveying gas into a fine fraction and a coarse fraction, said separator comprising: a rotor rotatable about a substantially vertical axis, said rotor having a top plate, a bottom plate and a plurality of vanes extending between said bottom plate and said top plate; said top plate having a distributing arrangement for distributing supplied, unsorted material to said rotor so as to suspend said material in said conveying gas; and a housing encasing said rotor and having an outlet from the upper end of said rotor for discharge of said fine fraction after separation; at least one inlet for the supply of said unsorted particulate material to the upper side of said rotor top plate; and an impact ring positioned around and at a radial distance from said top plate; an annular collecting casing secured to and coaxial with said top plate and displaced at a radial distance from said material inlet such that said casing is rotatable with said rotor and said top plate, said collecting casing having a concave side facing said top plate and configured with a vertical portion and a lower edge such that material flung outwards from said top plate is collected on said casing and forms a band of material substantially around the entire circumference thereof such that the surface of said band of material slides downwardly and is distributed over the entire circumference of the rotor.