Spray Dryer from GEA Niro
The conventional spray dryer is typically operated with a rotary atomizer or high-pressure nozzles for atomization of the concentrate. It is generally used for conventional food and dairy products. When the product leaves the drying chamber and the cyclone, it is collected in a pneumatic conveying and cooling system. This type of dryer is referred to as a one-stage spray dryer as the powder has its final moisture content when discharged from the chamber. For further reading please refer to Milk Powder Technology - page 71.
Many food & dairy products need to be dried this way, depending on their composition. But for products like milk and whey it is possible to perform the drying in two or more stages by replacing the pneumatic conveying and cooling system with a VIBRO-FLUIDIZER™. designed for second-stage drying.
All flowsheet animations are available in the GEA Niro download area.
On request the plant can be designed and delivered for full manual and/or automatic CIP Cleaning In Place including CIP Kitchen with tanks, pumps, valves and instrumentation.
The conventional spray dryer can now be operated in such a way that the moisture content in the powder when it leaves the drying chamber has a higher moisture content than is desired in the final powder. This is done by atomizing more concentrate into the same amount of primary drying air, which will then be utilized much better. For final drying in the VIBRO-FLUIDIZER™, a small amount of drying air at low temperature is needed. The overall energy consumption per kg of final powder is reduced by as much as 20 %. For further reading please refer to Milk Powder Technology page 131.
If the fines fraction from the cyclone and/or bag filter is returned to the atomization device, it is possible to produce agglomerated products instantly soluble in cold or warm water. For further reading please refer to Milk Powder Technology page 153