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Renin Angiotensin Mechanism.

Silverson Homogenizer.

 

Principle:

  • Silverson mixer emulsifiers produce intense shearing force and turbulence by the use of high-speed rotors. 

  • This turbulence causes the liquids to pass through fine space formed by closely placed perforated metal sheets. 

  • Circulation of material takes place through the head by the suction produced in the inlet at the bottom of the head. 

  • Circulation of the material ensures the rapid breakdown of the dispersed liquid into smaller globules.

Construction:

  •   It consists of long supporting columns connected to a motor that gives support to the head. 

  • The central portion contains a shaft, one end of which is connected to the motor and the other end is connected to the head. 

  • The head carries turbine blades. 

  • The blades are surrounded by a mesh, which is further enclosed by a cover having openings.

Working:

  • The emulsifier head is placed in the vessel containing immiscible liquids (or coarse emulsion) in such a way that it should get completely dipped in the liquid. 

  • When the motor is started, the central rotating shaft rotates the head, which in turn rotates turbine blades at a very high speed. 

  • This creates a pressure difference. As a result, liquids are sucked into the head from the center of the base and subjected to intense mixing action. 

  • Centrifugal forces expel the contents of the head with great force through the mesh and onto the cover. 

  • As a result, a fine emulsion emerges through the openings of the outer cover. 

  • The intake and expulsion of the mixture set up a pattern of circulation to ensure the rapid breakdown of the bigger globules into smaller globules.

Uses:

  1. Silverson mixer is used for the preparation of emulsions and creams of fine particle size.

Advantages:

  1. Silverson mixer is available in different sizes to handle liquids ranging from a few milliliters to several thousand liters.

  2. It can be used for batch operations. It is also used for continuous operation by incorporating into a pipeline, through which the immiscible liquids flow.

Disadvantages:

  1. Occasionally, there is a chance of clogging of the pores of the mesh.

  2. Foaming.


Commonly Asked Questions:

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

  2. Write a short note on Silverson Homogenizer.
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