Principle:
Works on the principle of Combined Impact and Attrition.
Diagram:
Construction:
It consists of a loop of metallic pipe with a diameter of 20 to 200 mm depending on the height of the loop, which may be around 2 m.
It has an opening for material feed.
The base of the mill has nozzles for inlet air under pressure.
The mill at the top has an opening with a classifier which acts as a product outlet.
Most of the time the outlet is connected with a Cyclone Separator for size separation of particles.
Working:
The material to be reduced in size is entered in the machine through the feed.
The nozzles at base introduce the air under pressure at high velocity which pushes the particles towards the wall.
The material moves in an elliptical path creating turbulence.
The size reduction takes place due to the impact of particles on the wall and interparticle friction.
The smaller particles are carried away with air at the top while the larger particles due to centrifugal force are thrown at the bottom and again get thrown away till they become small in size.
Other inert gasses can be used as per requirement of material.
The expanding and moving of air also cools down the heat generated by the mill.
The particles of the desired size range get separated by the classifier while others continue their journey with air flow.
Fluid energy mill is considered as one of the most efficient mills as it can produce particles up to 1 to 20-micron size.
Advantages:
Produces very fine particles.
Useful for heat sensitive materials.
Classifier provides the desired size product.
Continuous operation is possible.
No wear and tear: no contamination.
Variety of sizes is available as per the need of industry.
Disadvantages:
Not suitable for sticky products.
Applications:
To produce very fine particles at a large scale.
Commonly Asked Questions.
What is size reduction? Write Principle, Construction and working of Fluid Energy Mill.