FLUID BED DRYER - CONTINUOUS
A continuous fluid-bed dryer/cooler is a machine in which a continuous flow of damp, granular material is conveyed over a perforated bed, through which air is blown to bring about fluidization. The material is dried in the first section of the machine and cooled in the second. Drying occurs because of the direct contact between the damp material and the hot air blown through it. The air velocity is adjusted to keep the moving layer of material fluidized. The same mechanism applies to the cooling part of the process, except that the air used is either ambient or conditioned (ie cooled).
How It Works
FLUID BED DRYER - CONTINUOUS
A fluid bed dryer can handle up to 200 t/h and is used for drying of clay, sand, gravel, limestone, etc.
A continuous fluid-bed dryer/cooler is a machine in which a continuous flow of damp, granular material is conveyed over a perforated bed, through which air is blown to bring about fluidization. The material is dried in the first section of the machine and cooled in the second. Drying occurs because of the direct contact between the damp material and the hot air blown through it. The air velocity is adjusted to keep the moving layer of material fluidized. The same mechanism applies to the cooling part of the process, except that the air used is either ambient or conditioned (ie cooled).
The drying and cooling sections of the machine form a single conveyor in which the hot and cool air flows are segregated. Conveying of the product is achieved either by means of a low-frequency, high amplitude shaker mechanism.
Fluid bed dryers are specially preferred in mineral drying in combination with after cooling and heat recovery, resulting in better end product quality and very low energy consumptions.
Continuous Type Fluidized Bed Dryer (C-FBD): The hot air, blown from the gas dispersion plate (a perforated plate type) equipped at the bottom of the dryer and uniformly dispersed, fluidized and dries the wet material continuously fed. The processed material primarily dried is moved to a next drying chamber through a gap at the bottom of the partition plate and, after finally dried, discharged over the overflow gate.
Heat Transfer Units Built-in Type Continuous Fluidized Bed Dryer (CT-FBD): Heat transfer units (tube or plate type) are built inside the equipment. About 60% - 80% of heat capacity necessary for drying are supplied from the units. Consequently, the hot air volume can be decreased, the equipment becomes compact and auxiliary equipment is also miniaturized.
Advantages of continuous fluid-bed dryer system technology
Low energy consumption compared to other type of dryers
Accurate control of the residence time, product is dried uniformly
Gentle on sensitive materials (no friction)
Low operating costs
Cooling section integrated in dryer
Handling of sticky products (from centrifuges or filters)
Small footprint
Process flexibility
Reliable system, less downtime