Vibrating Fluid Bed Dryers

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Vibrating Fluid Bed Dryers

The Vibrating Fluid Bed Dryers are used for fluidization of materials which are difficult to handle in a static fluid bed dryer.


Physical Properties

These materials are often characterized by having one or more of the following physical properties:

  • Wide particle size distribution
  • Low strength of wet or dry particles
  • Stickiness or thermo plasticity of the particles
  • Pasty properties of the wet feed


In the vibrated fluid bed dryer, the material is easily transported through the dryer by the combined effect of fluidization and vibration. The fluidization velocity can be judiciously selected, to minimize entertainment of the smaller particles, to avoid gas bubbling m the fluid bed thereby minimizing attrition. The residence time can be adjusted, by varying the bed height, through the overflow weir position. A cooling section can also be provided, by partitioning of the plenum chamber.


Typical products handled:

  • Salt
  • Milk products (used as a secondary dyer)
  • Chemicals
  • Tea


Fluid bed dryer is suited for powder, granules with average particle size 50 - 2000 microns. If the feed material is sticky and having wide particle size distribution. Vibro fluid bed dryer is the most suited, where vibration helps the movement of solids and drying.


Operations

  • Material is easily transported through the dryer due to fluidization and vibration
  • Fluidization velocity can be judiciously selected to minimize entertainment of the smaller :particles
  • Minimize entertainment avoid gas bubbling m the fluid bed thereby minimizing attrition.
  • Residence time can be adjusted by varying the bed height, through the overflow weir position.
  • Provided with cooling section by partitioning of the plenum chamber.


Advantages

  • Well suited for constant
  • Well suited for failing rate drying
  • By preheating the air, the residual moisture can be reduced
  • Can fluidized well the solids having a well defined particle size