METHOD FOR PRODUCING GRANULAR COATED SODIUM PERCARBONATE AND PRODUCT OBTAINED ACCORDING TO SAID METHOD

• Main Authors: LATTICH, JUERGEN, OVERDICK, RALPH, HESSBERGER, WALDEMAR, JAKOB, HARALD
• Format: Patent
• Language: English; French; German
• Published: 18.05.2011
• Subjects: ANIMAL AND VEGETABLE OILS, FATS, FATTY SUBSTANCES AND WAXES; CANDLES; CHEMISTRY; COMPOUNDS THEREOF; DETERGENT COMPOSITIONS; DETERGENTS; FATTY ACIDS THEREFROM; INORGANIC CHEMISTRY; METALLURGY; NON-METALLIC ELEMENTS; RECOVERY OF GLYCEROL; RESIN SOAPS; SOAP OR SOAP-MAKING; USE OF SINGLE SUBSTANCES AS DETERGENTS

The invention relates to a process for the preparation of coated granular sodium percarbonate having a low TAM value. The preparation is carried out by fluidized-bed spray granulation at a temperature TG in the range from 45 to 75° C., and the coating is effected by the spray application of an aqueous solution containing at least one coating component in a fluidized bed at a temperature TU in the range from 35 to 100° C. According to the invention, a) after the fluidized-bed spray granulation but before the coating, drying is carried out at TNT of greater than TG, or b) the fluidized-bed granulation is carried out in at least two steps at TG1, TG2 . . . TGn, TG2 or TGn being higher than TG1, and drying being unnecessary if 2/3 of the granulate have been formed at TG1, or c) drying takes place not after the granulation but after the coating, at TUNT, TUNT being at least 20° C. higher than TG.