Two-stage evapn process partic for heat-sensitive solutes for - food, pharmaceutical and chemical prods

摘要

To obtain heat sensitive solutes from a soln., the solvent is evapd. in two separate evapg. chambers in succession, using heat and vacuum pressure in each chamber but with different conditions of temp. and/or press. in the two chambers. Not less than 50% and pref. 90% of the moisture is removed in the first chamber where the material spends a few mins. at ca 40 degrees C and ca 10 torr press. After transfer to the second chamber via a press. lock, the material is dried for several hrs. at ca 50 degrees C and 6.10-2 torr.