The GEA Niro FILTERMAT® dryer produces coarse or very coarse, agglomerated or granulated free-flowing dustless powders. The conventional spray dryer layout can handle drying at a certain temperature; any drying at a lower temperature requires a FILTERMAT® dryer.
The drying of hygroscopic, thermoplastic and slowly crystallising products involves handling of very sticky intermediate materials at a lower temperature level than that possible in conventional spray dryer layouts.
Completion of drying requires the powder to be processed at close to critical conditions for a long time.
THE FILTERMAT® PROCEDURE
The FILTERMAT® spray dryer uses nozzle atomization in a co-current tower that directs the semi-dried particles downward onto a moving belt. The material is then gently conveyed as a porous layer through zones of post-drying and cooling, resulting in a crisp cake-like structure, which breaks up at the end of the belt and is discharged through a final particle size control system. The exhaust air streams pass through the material layer on the belt.
FURTHER READING: FILTERMAT® dryer