Spray Bed Dryers - Function and Principle of Operation
The drying process involves product being atomized as a fine spray, which mixes with recycled fines and the fines elutriated from the integral fluid bed. The primary air flow enters at the top of the chamber; the secondary air flow enters through the fluid bed where second stage drying occurs.
The agglomerated products falling into the bed are dried to the correct moisture content before being discharged from the chamber.
To optimize the control of particle size, the product caught in the spent drying air is separated out in the cyclone or textile filter and returned to the atomization zone in the drying chamber. The degree of agglomeration and particle size is influenced by operating conditions, which alter residual moisture level of particles within the atomization zone. A wide range of particle sizes can be formed. Both soluble and insoluble products can be agglomerated in this process.
From 5 kg/h to 10 t/h
- Open cycle systems applying atmospheric drying air
- Closed cycle systems, either as low-Ox or inert gas (nitrogen)
- High thermal efficiency
- Improved control over particle size distribution
- Minimum of fines
- Straightforward CIP
- Customized to individual requirements
- Proven reliability and high availability
- Long service life
The Spray Bed dryers are used for a wide range of applications where energy-efficient drying and non-dusty end-products are required under hygienic conditions. They are designed to dry and agglomerate heat-sensitive materials, but can also be used for powder conditioning e.g. lecithination.
The Spray Bed Dryers are used in the dairy, food & beverage, pharmaceutical and chemical industries to produce dust-free, agglomerated, dispersible, and free-flowing powders. The typical product applications for the Spray Bed Dryers are food ingredients, yeast products, plant extracts, flavours and fragrances, agro chemicals, tanning agents, dyestuffs, fertilizers and detergent ingredients.