Fluidized Bed Dryers & Coolers are used for particles over about 150 uM in size. Hot or cold air are used to convey energy in or from the product particles. The air is fluidizing the product which explains the name of the dryer. Energy efficiency can be very high and processing times medium long from few up to 30 minutes.
Flash Dryers & Coolers are used for finer particles from few microns up to 150 uM in size. Hot or cold air are used to convey the product while product is dried or cooled. Energy efficiency is usually less than with Fluid Bed Dryers and processing times are from few up to 30 seconds. This type of dryer can be fed with dewatered solids, as well with slurries and solutions.
Spray Dryers are used to obtain fine dry solids. They are fed with pumpable slurries or solution and are widely used for production of milk powder and coffee as well other foods, fine chemicals, minerals and ceramics.