GEA Niro FSD™ spray dryer
GEA Niro FSD™ spray dryer

The GEA Niro FSD™ spray dryer combines spray drying and fluid bed drying into Fluidized Spray Drying. It produces an attractive coarse, agglomerated, free-flowing dustless powder that is used as a benchmark worldwide. With a mean particle diameter (D50) between 0.1 – 0.4 mm (depending on the product), it is applied for production of dyestuff, agrochemicals, inorganic saltsorganic salts, tannins and a vast number of other products.

The Fluidized Spray Dryer concept was developed by GEA Process Engineering (then Niro) around 1980 to improve energy efficiency and final product quality in spray drying without causing problems with deposits in the drying chamber. Since then the design has been developed continuously making it still a state-of-the-art spray dryer.

All flowsheet animations are available in the GEA Niro download area.

Drying in more stages 
The GEA Niro FSD™ spray dryer operates with two or three drying stages, each adapted to the moisture contents of the drying process. Atomization is done by co-current nozzles. The air enters the spray dryer vertically through the air disperser at high velocity, ensuring optimal mixing of the atomized droplets with the drying air.

At high moisture content, the powder may exhibit thermo-plasticity and becomes sticky which helps the required agglomeration. The air flow in the spray dryer is designed to prevent particles from sticking to the walls of the drying chamber, and instead be led directly into the integrated static fluid bed for second-stage drying.

When the powder has reached a certain moisture content, it can be discharged into a GEA Niro VIBRO-FLUIDIZER™ for final drying and subsequent cooling. The drying/cooling air from the chamber and VIBRO-FLUIDIZER™ is passed through a bag filter to seperate the fine powder, which is returned back to the atomization device, the static fluid bed, or the VIBRO-FLUIDIZER™ for optimizing the powder characteristic. The VIBRO-FLUIDIXER™ can be replaced by a Triple-Bed as is used in the GEA Niro IFD™ Integrated Filter Dryer. The combined spray drying and fluid bed drying makes the GEA Niro FSD™ concept very energy efficient. 

Powder from a GEA Niro FSD™ spray dryer
Powder from a GEA Niro FSD™ spray dryer
Additional agglomeration
For even more agglomeration than than can be obtained by returning the the fines back into the drying chambers, the GEA Niro FSD-GRANULATOR™ can be applied. This patented GEA Niro system allows additional liquid to be added in the stationary integrated fluid bed – a feature that is not possible in traditional spray dryers. The liquid may be water, a liquid with the same composition as the feed, a melt or a solution containing different substances.

Safety aspects
All GEA Niro spray drying plants comply with the strictest requirements for health, safety and environmental compliance. GEA Process Engineering's expertise in explosion control design is unequaled and an invaluable aid whether considering ATEX, other European safety directives or local regulations. All plants designed and supplied by GEA Process Engineering will enable the end user to obtain approvals put forward by the EU directive.