Fluid Bed Processing Systems

Niro has been a world leader in fluid bed processing technology for nearly half a century and has supplied systems for many global customers. Shown below are some fluid bed systems commonly used in food and dairy applications. Call your Niro representative for knowledgeable advice on the best system for your exact requirements.

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.

Drying/Cooling

These are the most frequent applications of fluid beds. Different process systems are applied depending upon product, volatiles, operational safety and environmental requirements.

Open system

Featuring atmospheric air in a once-through system where water is to be removed. Normally a push-pull system is used to balance the pressure to be slightly negative in the free board of the fluid bed. Depending upon the product and available heat source, direct or indirect heating may be applied. The exhaust air is cleaned by e.g. bag filter, cyclone with or without wet scrubber.

Open System Fluid Bed System

In cases where products pose a dust explosion risk, open cycle systems feature pressure shock resistant components or alternatively semi-closed cycle, self-inertizing layouts can be considered.

Agglomeration / Granulation

Fluid bed processing requires that the solids are in particulate form prior to entering the fluid bed. In the special case of fluid bed spray granulation, particles are built up in the fluid bed by spraying a liquid into the fluidized layer particles. Particulate solids ideal for fluid bed processing may be formed in an independent process step such as crystallization, coagulation, or polymerization, followed by mechanical dewatering. Particles may also be formed by spray drying. In other cases dry or wet solid particles may have to undergo a degree of agglomeration or granulation prior to entering the fluid bed.

Rewet agglomeration system

Rewet Agglomeration

In the rewet agglomeration system, a fine powder is conveyed to an agglomeration chamber where the powder is dispersed in air and contacted with a spray of liquid. Moist, porous agglomerates are formed and subsequently dried under lenient fluidization conditions in a Vibro-Fluidizer®. After cooling, the powder is discharged, classified, and fines recycled for further agglomeration together with fines from the exhaust air dust collector. Rewet agglomeration systems are typically used for food products like coffee, cocoa-sugar, where instant properties and coarse particles are required.

Inquiries outside North America and more information on Fluid Bed Processing Systems. For other types of fluid bed dryers and fluid bed processors handled by our sister company, Barr-Rosin, please access page titled Products - Fluid Bed Dryer