• Fundamentals of Fluid Bed Drying             Back to GEA NIRO
• Fluid Bed Types
• Fluid Bed Designs
• Fluid Bed Process Systems
• Industry Applications

Each NIRO fluid bed is selected for its industrial application to fulfill a number of requirements dictated by the material to be processed. The examples below illustrate the variety in design necessary to achieve optimum processing.

Two-tier dryer for polymer
The upper back-mix fluid bed with heating panels is for pre-drying. The pre-dried material is transferred to the lower plug flow fluid bed through an external down-comer. As the polymer contains organic volatiles, nitrogen is the drying gas and the fluid bed a closed cycle gas tight design.

Four-stage dryer for organic product
The fluid bed has four stages for individual control of the drying air temperature. The material being handled is dust explosive, and therefore the bed is pressure shock resistant and provided with explosion membranes.

Three-stage dryer for bulk chemicals
Atmospheric air is used for drying in two stages followed by cooling. The first drying stage is back-mixed because of the poor fluidization characteristics of the feed material. The fluid bed is prefabricated in one piece in the workshop to minimize field erection.

Vibro-Fluidizer for sanitary operation
This vibrating fluid bed is used for drying a food product that demands a high standard of hygienic processing. All corners in the fluid bed in contact with product are rounded, and the distributor plate is supported in a way that permits effective cleaning and meets USDA standards.

Successful performance of a fluid bed requires proper functioning of a number of important components controlling feed and gas distribution, product discharge, emptying, and heat transfer.

Gas distributor
Even and stable distribution of the fluidizing gas is a prerequisite of sustained operation. NIRO has developed its own patented distributor plates to obtain optimum fluidization and powder movement during operation, and to prevent powder penetration through the plate on plant shut-down. A special design with directional gas flow makes processing of oversized particles possible and the bed self-emptying even in non-vibrating designs.

Heating panels
In many applications, heating surfaces give better heat economy and lower plant investment costs.

The heating panels are ideal for both heat and non-heat sensitive products. In the case of heat sensitive products, panels have an important advantage over tubes due to absence of horizontal surfaces where product can build up and deteriorate. Heating panels are easily removable.

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