PURPOSE: To form granules having uniform grain sizes with good efficiency and high yield by feeding hot air to a granulation chamber through multilayered plates formed by uniting many concentrically disposed annular plates having different diameters to one body by spacing the plates from each other above and below.
CONSTITUTION: The multilayered plates 2 provided in a granulation chamber consists of many annular plates 4 of different diameters which are disposed in the concentrical layers of the diameters increasing toward the lower part and are united to one body after the plates 4 are spaced from each other above and below by means of a suitable number of spacers 5 disposed circumferentially equidistantly. How air is supplied from a supply hole 20 and is fed through the plates 2 into the granulation chamber. The plates 2 are rotated at a prescribed speed, and powder is charged from above into the granulation chamber, then a binder soln. is sprayed and the powder is granulated. The hot air blowing out through the plates 2 flows in a centrifugal direction and the rotating direction of the plates 2, thus generating circumnutating gaseous flow and centrifugal gaseous flow. The uniform mixing of the charged powder and particles is thus effected, whereby the spherical granules having roughly specified grain sizes are obtd. The hot air is removed by a discharging means 50.
ITOU YOSHIHIRO
KAMATA TETSUO