1. Agitator types, application & function, 2. No. of agitator calculation 3. Introduction 4. Agitator? 5. What It can do? 6. Agitation Vs Mixing 7. Laminar Vs Turbulent Flow 8. Agitators Types & Applications 9. Agitators Types & Function 10. No. Of Agitators Calculation

2. Contents:
Introduction
Agitator?
What It can do?
Agitation Vs Mixing
Laminar Vs Turbulent Flow
 Agitators Types & Applications
 Agitators Types & Function
 No. Of Agitators Calculation

3. Introduction:
 What Agitator Do??
It can be used in various operations like reactions,
work up's, drying, filtration etc.
Agitator??
An agitator is something which is used to stir
liquid or mixture of liquids.

4. Introduction:
Agitation and Mixing:
Agitation Mixing
Agitation is the process of keeping a
mixture that has been mixed in the proper
mixed state required for the 'end' product.
Mixing refers to the actual stirring of
different liquids and/or materials to blend
them together into an end product or
mixture.
Forcing a fluid by mechanical means to
flow in a circulatory or other pattern in a
vessel.
Blending of 2 or more separated phases,
such as a fluid and a powdered solid, or 2
fluids, and causing them to be randomly
distributed through one another.
E.g. Agitator of reactor / vessel etc. E.g. Circulation of fluids in tank through
pump.

5. Introduction:
Agitation and Mixing:

6. Flow By Agitators

7. Agitator Types
•Two types of Agitators commonly used,
1.Mechanical Agitators,
2.Electronically Controlled Agitators,
Note: We will discussed commonly used Mechanical
Agitators.

8. Agitator Types:
•Paddle Agitators:
This is one of the most
primary types of agitators
with blades that reach up
to the tank walls.
Paddle agitators are used
where an uniform laminar
flow of liquids is desired.

9. Paddle Agitators Application:
Agitator
Type
Applications Advantages Disadvantages
Paddle
* Mixing of Solids,
* Slurry Mixing,
* Used during
Crystals
forming phase
during
Super saturated
Cooling
* Heavy duty,
* Apt for Slow
operation,
* Can have 2 or
4 blades
* Power
Consumption is
very high,
* Inefficient
Mixing

10. Agitator Types:
•Anchor Agitators:
This simple agitator
consists of a shaft and an
anchor type propeller.
 Mounted centrally or
at an angle.
Mainly used in
reactors.

11. Anchor Agitators Application:
Agitator Type Applications Advantages Disadvantages
Anchor
* Highly used
in Pharma
Industry for
Several
Operations
* Increase
possible
heat transfer
rate in reactors,
from reactor
heat transfer
surface to Mass.
* Required high
Efficiency
Gearbox,
* Required high
Power.

12. Agitator Types:
•Radial Propeller Agitators:
It consist of propellers that
are similar to marine
propellers.
They consist of two to four
blades that move in a screw
like motion, propelling the
material to be agitated
parallel to the shaft.

13. Agitator Types:
•Propeller Agitators:
It is shaped with blades
tapering towards the shaft
to minimize centrifugal
force.
It produces maximum
axial flow.
It is popular for simple
mixing jobs.

14. Propeller Agitator Application
Agitator
Type
Applications Advantages Disadvantages
Propeller
* Suitable for
GLR's, ANFD's,
can handle
Corrosive
materials with
Glass lining.
* Will increase
the homogeneity,
* Can be used in
two different
patterns for
drying and
pressing.
* Need to be
operated at high
speed to avoid solid
settlings in reactors.
* Need to be
operated at low
speeds in drying
operations.

15. Agitator Types:
•Turbine Agitators:
It can create a turbulent
movement of the fluids due to the
combination of centrifugal and
rotational motion.
Sub Classifieds:
Disc mounted Flat Blade Turbine
Hub Mounted Flat Blade Turbine
Hub Mounted Curved Blade
Turbine
Shrouded Turbine Impeller

16. Turbine Agitator Application:
Agitator Type Applications Advantages Disadvantages
Turbine
*Straight Blade
*Pitched Blade
*Curved Blade
*Disk Blade
* Liquids and
Gas reactions,
* Highly used
during Reaction
and Extraction
Operations.
* Generates
high Radial
Flow,
* Highly used
for dispersion
operations
* Not preferred
for solvents
with
high viscosity[
NMT 20 cP]

17. Agitator Types:
•Helical Agitators:
It has blades with a twisted
mechanism, just like the threads
of a screw.
The curves result in a vigorous
motion of the fluids to be
agitated.
Are most useful for mixing
viscous liquids.

18. Helical Agitator Application:
Agitator Type Applications Advantages Disadvantages
Helical Blade
*Ribbon Type
*Helical Screw
* Most Probably
used in Paint
industry.
* Can handle
Visco-elastic
liquids
efficiently
* Low
possibility for
Radial mixing
Screw type
* Have to use in
addition to other
agitators.
* Mostly used in
Food processing.
* Uniform
mixing of High
viscous
masses.
* Not preferred
for im-miscible
solvents.

19. Agitator Types & Function:
Marine Propeller:
It is produced by casting process in a foundry.
It has 3 or 4 blades.
Cast agitators have two basic advantages, uniformity of
material and hard surface.
These have tapering blades, and angle of blade varies
from root to tip.
This produces maximum axial flow.
The diameter of Marine Propeller impeller is 15% to 30%
of diameter of tank.
These have tip speeds between 300 to 500 meters per
minute.

20. Agitator Types & Function:
Axial Flow Turbine, Turbo Propeller and Flat Blade Turbine
 It has blades ranging from 3 to 6.
These have tip speeds between 200 to 300 meters per minute.
The diameter of impeller is 25% to 60% of tank diameter.
For Axial Flow Turbine and Turbo Propeller, the angle of blade
varies from 30 degrees (for less viscous liquids) to 60 degrees
(for more viscous liquids).
Standard angle is 45 degrees.
Power requirement increases with higher pitch angle.
For Flat Blade Turbine, the length of blade is 25% of diameter,
and disk diameter is 60% to 70% of the diameter of impeller.

21. Agitator Types & Function:
Paddle, Anchor, or Gate
It has only 2 blades.
These extend close to the tank wall.
It has tip speeds between 80 to 150 meters per
minute.
These push and rotate the liquid in a laminar flow.
 There is no axial or radial mixing.
The width of blade is 1/8th or 1/10th of the agitator
diameter.

22. Number of Agitators:
There can be many number of agitators
connected to a shaft, and it can be calculated
as below:
No. of Agitators = (Max. Liq. height x Sp.Gr.)
Diameter of tank.
Gap between two Agitators
= Liquid height
(No. of impellers - 0.5)

23. Agitator Types & Function:
Paddle, Anchor, or Gate
It has only 2 blades.
These extend close to the tank wall.
It has tip speeds between 80 to 150 meters per
minute.
These push and rotate the liquid in a laminar flow.
 There is no axial or radial mixing.
The width of blade is 1/8th or 1/10th of the agitator
diameter.