Removal of solvent from particulate materials - using steam heated screw feeder discharging into fluid bed with spiral movement fluidised by superheated solvent vapour

摘要

Solvent removal from particulate material is carried out in a fluid bed. The material is supplied by a screw, which is externally heated by steam. The solids are fed down a vertical chute onto a horizontal perforated plate. This has vapour box below into which superheated solvent vapour and steam are injected. The solids move across the plate by means of a spiral guide. The reach the centre where there is a standpipe, down which they flow. At the end of this is a further point for steam injection and it discharges into a further screw. The solvent can be removed without thermal damage to the product. Thus a rise in product quality is achieved.