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Renin Angiotensin Mechanism.

Double Cone Blender.

 

Principle:

  • It's a “Tumbling Mixer”.

  • It works on the mechanism of Diffusive Mixing.

Construction:

  •  It consists of a vessel with conical ends as shown in the figure.

  • All the contact parts are made up of stainless steel.

  • The vessel is mounted on a metal frame on which it can be rotated.

Working:

  • The materials to be mixed are introduced to the mixer through one of the ports.

  • The mixer is loaded approximately two thirds of the volume to allow tumbling of the powders.

  • When the mixer is started, it rotates along the axis.

  • The tumbling movement during rotations causes mixing.

  • The speed of the mixer plays an important role in the mixing,

    • If rotations are slow: Mixing will not take place as materials will just glide over one another.

    • If rotations are very fast it will cause generation of centrifugal forces hence powders will remain adhered to the walls and hence no mixing will take place.

    • For better results the double cone blender needs to be operated at an optimum speed.

Uses:

  1. For mixing a variety of powders and granules.

Advantages:

  1. Minimum attrition and hence good for fragile granules.

  2. Easy to clean, load and unload.

  3. Minimum maintenance cost.

  4. Available in different sizes.

Disadvantages:

  1. More space is required.

  2. No application of shear and hence not useful for materials with large particle size distribution.

  3. Suitable for free flowing powders and granules only.

Commonly Asked Questions:

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

  2. Write a short note on Double Cone Blender.
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