VERFAHREN UND VORRICHTUNG ZUR WIRBELSCHICHTSPRUEHGRANULATION

• Main Authors: DAUN, HANS, 5090 LEVERKUSEN, DE, UHLEMANN, HANS.., 5650 SOLINGEN, DE, BOECK, REINHARD, 4040 KAARST, DE, HEROLD, HEIKO., 4040 NEUSS, DE
• Format: Patent
• Language: German
• Published: 21.09.1989
• Subjects: CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOIDCHEMISTRY; OTHER SEPARATING BY DRY METHODS APPLICABLE TO BULK MATERIAL,e.g. LOOSE ARTICLES FIT TO BE HANDLED LIKE BULK MATERIAL; PERFORMING OPERATIONS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; SEPARATING SOLIDS FROM SOLIDS; SEPERATING SOLIDS FROM SOLIDS BY SIEVING, SCREENING, ORSIFTING OR BY USING GAS CURRENTS; SORTING; THEIR RELEVANT APPARATUS; TRANSPORTING

Granulation is based on the grain growth in a fluidised bed (4), the liquid starting product being sprayed into the fluidised bed and the finished granulated grain being discharged from the fluidised bed (4) with classification. The classification is carried out by means of a classifying air stream which is divided into individual single streams (6), each of which is associated with a zig-zag classifier module (7, 17) and a spray nozzle (5) or group of spray nozzles. The classifying process proceeds in such a way that granule grains which are too small and have not yet reached the desired diameter are flung back by means of in each case one recycling shaft (9, 18) placed on top of the zig-zag classifier module (7, 17) into the fluidised bed (4) in mutually parallel or radial zones without cross-mixing, the relatively small grains impinging at a relatively large distance and the large grains, which have already grown almost to the discharge size, impinging at a relatively small distance from the recycling shaft (9, 18). The process is carried out by means of a fluidised-bed granulator, to the inflow plate (2) of which a zig-zag classifier subdivided in the manner of a module is connected, each zig-zag classifier module (7, 17) being provided on the site of the connection to the inflow plate (2, 16) with a recycling shaft (9, 18). In addition, each zig-zag classifier module (7, 17) is associated with at least one spray nozzle (5) on the inflow plate (2,16).