PURPOSE: To contrive to obtain at high yield granule and powder in small and uniform diameter by providing a rotating nozzle exhausting dispersion air stream and a dispersion air stream feeding mechanism feeding diffusion air stream inside of said rotating nozzle.
CONSTITUTION: The mechanism 29 feeding air stream for diffusion is composed of the diffusion air stream nozzles 30 provided on the peripheral wall of a rotating nozzle 28 so as to be connected to the inside of said nozzle 28, and the diffusion air stream feeding part feeding the diffusion air stream to said nozzles 30. The diffusion air stream nozzles 30 are arranged in the positions almost symmetrical in relation with the axial direction of the rotating nozzle 28. These diffusion air stream nozzles 30 are arranged in such a manner that the diffusion air streams are, for instance, supplied in the directions crossing mutually downward obliqualy in relation to the axis of the rotating nozzle 28 inside of said nozzle 28. From the opening of the rotating nozzle 28, the dispersion air stream of powder and granule is exhausted downward while swirling at the state where the thickness D of the air stream layer of an empty cone shape is increased. Consequently, the space density of the powder and granule in the dispersion air stream is decreased, whereby the powder and granule are fully dispersed in low density.
SAITO ATSUSHI
KUBOUCHI KAZUHIRO
