METHOD OF PRODUCTION OF SODIUM PERCARBONATE AND DEVICE FOR REALIZATION OF THIS METHOD Russian patent published in 2001 - IPC

FIELD: chemical industry; manufacture of detergents and bleaching agents. SUBSTANCE: H₂O₂ and Na₂CO₃ solution are fed to reaction 1. Sodium percarbonate thus produced in reactor 1 is fed to double-worm mixer 2 loaded preliminarily with seeding particles (recycle) of sodium percarbonate, 0.1-0.3 mm in size. These particles are moistened in mixer 2 and are increased in size, then they are mixed and shifted to drier 3. Axis of mixer 2 is located at angle of 10-30 deg relative to gas distributing grate 5 of drier 3. Part of dried granules are returned to mixer 2 through branch pipe 6. Some of dried granules in the amount of 0.01-0.05 part are removed from drier 3 to classifier 5. Middle fraction having particles of 0.1-1.0 mm in size are directed from intermediate part of classifier 4 to finished product accumulator through injector 18. Coarse fractions are ground in mill 15 where they are mixed with fine fractions and are returned to mixer 2 as additive for recycle. Bulk density of granules is 1.02-1.25 g/cu.cm, mass fraction of active oxygen is 13.1-15 % and mass fraction of losses at drying ranges from 0.8 to 1.56 %. EFFECT: reduced power requirements. 8 cl, 2 dwg, 1 tbl, 1 ex