METHOD AND APPARATUS FOR SPRAYING AND GRANULATING OF FLUIDIZED BED

PURPOSE: To classify granular particles with high accuracy in site of a large treatment quantity by dividing a granulation chamber to a plurality of uniform zones, providing each zone with a zigzag classification module and spray nozzle and returning granular particles by a return shaft into a fluidized bed without cross-mixing. CONSTITUTION: The fluidized bed 4 is maintained by a fluidizing gas 3 above an inlet plate 2 and a fluid start material for forming granules is sprayed via a duplex nozzle 5 into the fluidized bed 4. As a result, the particles increased in diameter and salidified in the fluidized bed 4 are released through a classifying air flow 6 in the zigzag classification module 7 from a cellular wheel flow passage 8. The module division of the granulation chamber enables the prescribed particles circulation and while the fine particles are reset into the bed at a large flying distance, the coarse particles fall down into the bed near the return shaft 9 and, are therefore, more frequently divided. The controlled discharge prevents the cross mixing of the particles.