METHOD OF PRODUCING GRANULAR SYNTHETIC DETERGENT Russian patent published in 2012 - IPC C11D11/02 

FIELD: chemistry.

SUBSTANCE: method is realised in an apparatus shown on dwg.1. The method involves dividing a synthetic detergent composition into two streams, one of which is sprayed by nozzles uniformly fitted in the horizontal plane on the periphery of the upper level of a cylindrical drying chamber. The second stream is sprayed by nozzles lying below the spraying level of the first stream. Moisture content of particles of the synthetic detergent in the drying chamber on the spraying level of the second stream must in the range of 15-25%. The sprayed composition is dehydrated in an ascending stream of a heat carrier which is fed on the lower level of the drying chamber and comes out from the upper level into a cleaning system. Dust from the heat carrier cleaning system is fed into the zone of the bottom of the drying chamber and mixed with the discharged powder. The dust fraction is separated from the powder in an airlift separator and comes out of the process as the ready product - granular synthetic detergent with residual dust content. The dust separated from the powder is returned into the drying chamber and fed into the spraying zone of the second stream, wherein the dust is fed into the near-wall annular region of the drying chamber towards the bottom with minimum distance from the axis of the drying chamber 0.85R, where R is the radius of the drying chamber.

EFFECT: efficient utilisation of dust when feeding it into the drying chamber, avoiding significant accumulation of dust in the apparatus and providing high consumer properties of the product.

1 cl, 4 ex, 4 tbl, 2 dwg