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Renin Angiotensin Mechanism.

Super Centrifuge.

 Super Centrifuge.

Centrifuge:

  • The equipment used for the process of centrifugation is called a Centrifuge.

  • The centrifuges are of two types as following,

  1. Sedimentation centrifuge:L

  • It is a centrifuge that produces sedimentation of solids based on the difference in the densities of two or more phases of the mixture. 

  1. Filtration centrifuge:

  •  It is a centrifuge in which solids pass through the porous medium based on the difference in the densities of the solid and liquid phases.

Super Centrifuge. 

  •  Super Centrifuge is a continuous centrifuge used for separating two immiscible liquid phases.

Principle:  

  • It is a sedimentation centrifuge. 

  • The separation is based on the difference in the densities between two immiscible liquids. 

  • Centrifugation is done in the bowl of a small centrifuge. 

  • During centrifugation, the heavier liquid is thrown against the wall, while the lighter liquid remains as an inner layer. 

  • The two layers are simultaneously separated using modified weirs. 

Construction:  

  • It consists of a long hollow cylindrical bowl of small diameter. 

  • It is suspended from a flexible spindle at the top and guided at the bottom by loose-fit bushing. 

  • Two liquid outlets are provided at different heights at the top of the bowl, for simultaneous recovery of the separated liquids using modified weirs.  

Working:  

  • The centrifuge is allowed to rotate on its longitudinal axis at a high frequency usually about 2000 revolutions per minute with the help of drive-assembly. 

  • The feed is introduced from the bottom of the centrifuge using a pressure system. 

  • During centrifugation, two liquid phases separate based on the difference in their densities. 

  • The heavier liquid is thrown against the wall, while the lighter liquid forms an inner layer. 

  • Both liquids rise to the top of the vertical bowl. 

  • The liquid-liquid interface (the so-called neutral zone) is maintained by a hydraulic balance. 

  • These two layers are simultaneously separately removed from different heights through modified weirs. 

  • Thus the super centrifuge can work for continuous separation of immiscible liquid phases.

Uses:  

  1. It is used for separating liquid phases of emulsions in food and pharmaceuticals. 

Commonly Asked Questions.

  1. Write a short note on Super Centrifuge.
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