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Renin Angiotensin Mechanism.

Mixing: Ribbon Blender.

 

Principle:

  • It's an “Agitator  Mixer”.

  • It works on the mechanism of Shear and Convective Mixing.

  • This type of mixers employs a stationary container to hold the material and brings about mixing by means of moving  screws, paddles or blades.

Construction:

  •  Consists of a U shaped horizontal shell with an opening lid.

  • Shell contains a double helical ribbon agitator that rotates inside the shell.

  • The agitator shaft is fixed on the inside wall of the shell.

  • The shaft can have an attachment of spray.

  • Depending on the application the gap between the agitator and the wall is maintained from 3-6 mm.

  • Feed material can be charged through the lid.

  • The shell may have an external jacket for warming or cooling.

Working:

  • The materials to be mixed are introduced to the mixer through the lid.

  • The mixer is loaded approximately 40-70% of the volume to allow tumbling of the powders.

  • When the mixer is started, the one set of agitator blades moves powder in one direction while the other set moves powder in the opposite direction.

  • The powders are lifted and are allowed to cascade at the bottom of the container.

  • After mixing the material is removed by opening the lid.

  • Material with similar size and density mixes faster than the materials with density difference and particle size change.

Uses:

  1. For mixing large volumes of dry solids.

  2. Solid liquid mixing.

  3. Lubrication of dry granules.

  4. Coating of powders with a small amount of liquids.

Advantages:

  1. Batch and continuous operation.

  2. Ability to cool or heat the materials.

  3. Place required is comparatively less.

Disadvantages:

  1. Damage to fragile substances.

  2. Less application of shear.


Commonly Asked Questions:

  1. Define Mixing. With help of a diagram describe the principle, construction and working of the Ribbon Blender.

  2. Write a short note on Ribbon Blender.
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