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Renin Angiotensin Mechanism.

Propellers.

 

Introduction:

  • Propeller is a device which is used for liquid-liquid mixing.

  • It consists of a propeller rod attached to the propeller blades,

  • Propeller blades used are generally like blades of a fan and are called marine types.

  • The blades are arranged in different ways to force the liquid in different directions.

  • Propeller blades move at a very high velocity, i.e. 400 to 1750 rpm.

  • Lower speed is used for small volume mixing and products which are little viscous in nature, while higher speeds are used for mixing of large volume products and the liquids with low viscosities.

  • The position of the propeller in the mixing vessel plays an important role in order to get complete mixing, some arrangements are: Side entering, off center, off center inclined and bottom entering.

Uses:

  •  Used when high capacity mixing is needed.

  • For mixing the substances with lower viscosity.

Advantages:

  1. Minimum time required for mixing.

  2. Much smaller in diameter than turbines and paddles.

Disadvantages:

  1. Not effective for more viscous substances.

  2. Vortex formation and foaming.


Commonly Asked Questions:

  1. Write a short note on Propeller mixers.
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