PROCESS FOR PRODUCING GRANULATES USEFUL AS WETTING, WASHING AND/OR CLEANING AGENTS

摘要

Loose and pourable granulates of valuable substances or mixtures of valuable substances are produced from their aqueous solutions and/or suspensions by spray drying or by fluidized bed spray granulation or the like with a stream of overheated gas within a drying reactor. Overheated steam is used as drying gas during one or several drying steps. The drying process is interrupted before the product is thermally damaged and if required the storage-stable looseness and pourability of the partially dried product are ensured by admixture of components capable of binding limited amounts of water and/or by a subsequent treatment. The system is a closed system in which a steam current circulates, from which the water evaporated from the process substance is drawn as a partial current and to which the released thermal energy is supplied again. The circulating steam current is cleared from entrained parts of the process substance by means of filters made of fabrics and/or felts. Optimized process features concern the circulation of steam.