Reprocessing of residues from prodn. of concrete flow improvers, etc.

摘要

A process is claimed for working up residues from the prodn. of flow improvers (I), contg. gypsum, water and dispersed flow improvers of the naphthalenesulphonic acid/formaldehyde polycondensate (NSF) or sulphite-modified melamine/formaldehyde resin (MFS) type. The process comprises pre-crushing the moist filter cake and then drying it in an indirectly heated kneader/drier fitted with size reducing elements and filled to a level of not more than 65%, to give segregated solid particles.