cyclone separator, procedures and operations

1. Cyclone Separator /
Centrifugal Separator

2. Overview
• Basic Definition
• Objectives
• Working Principle
• Design Procedure
• Types
• Advantages/Disadvantages
• Industrial Usage

3. A centrifugal separator
stationary mechanical device that utilizes centrifugal force
toseparate solid or liquid particles from a carriergas
Cyclones have no moving parts and available in many shapes and sizes, for example
from the small 1 and 2 cm diameter source sampling cyclones which are used for
particle size analysis to the large 5 m diameter cyclone separators used after wet
scrubbers.
What it is…

4. Classification of the
dust collectors…

5. Forces
Inertia
a property of matter by which it continues in its existing state of rest or uniform motion in a straight line, unless
that state is changed by an external force.
Centripetal force
a force that acts on a body moving in a circular path and is directed towards the
center around which the body is moving.
Centrifugal force
a force, arising from the body's inertia, which appears to act on a body moving in a
circular path and is directed away from the center around which the body is moving.

6. The flow enters near thetop
through the tangential inlet, which gives rise to an axially descending spiral
of gas and a centrifugal force field that causes the incoming particles
to concentrate along, and spiral down, the inner walls of the cyclone separator.
Working principle
The collected particulates are allowed to exit out an underflow pipe whilethe
gas phase reverses its axial direction of flow and exits out
through the vortex finder (gas outlet tube) .

7. Lets make things abit
clear… Vortex Finder
Tangential inlet duct
Barrel
Cone
Dust Collector

8. Design procedures

9. Vertical cyclone separator
Horizontal cyclone separator
Multiple cyclone separator Single cyclone separator
TYPES

10. Design Parameters
a = inlet height
b = inlet width
Dx = vortex finder diameter
Ht = total height of cyclone
h = cylinder height
S = Vortex finder diameter
Bc = cone tip diameter

11. Working Principle
• The particle laden gas is introduced through a
tangential inlet into the cylinder at high velocity
which imparts a whirling motion to the gas by
generating a centrifugal force.
• Centrifugal force acting on particles in a spinning
gas stream is greater than the gravitational
force.
• Particles of much smaller size can be eliminated
as compared to gravity settlers.
• The particle laden gas undergoes a spiral motion
directed towards the cone.

12. • The vortex develops enough centrifugal
force to throw the particles radially
towards the walls of the cone.
• At the bottom of the cone, the gas flows
in the reverse direction to form an inner
vortex spirally upwards until it exits from
the cyclone.
• The separated particles slide down the
cylinder owing to the gravitational force
and collect at the bottom.

13. • The commonly employed equipment have a tangential inlet with
axial dust discharge.
• The other variants include tangential inlet with peripheral dust
discharge, axial inlet with axial dust discharge or peripheral dust
discharge.
• Cyclones are generally sized from the diameter of the cylinder.
• The ratio of typical parameters could be derived with respect to
the cylinder diameter D0.

14. • The body force acting on the particle is given by ‘mg’ where
m - mass of particle
g – centrifugal acceleration
The unbalanced centripetal force acting on the particle is
fc = mVt/r
Vt  tangential velocity of the particle
R  radius of rotation

15. • The design factors have greater effect on the collection
efficiency in cyclone separator
• Smaller diameter, higher is efficiency because centrifugal action
increases with decreasing radius of rotation
• Cyclone efficiency is >90% with particle diameter of <10 microns
• >95 % with particle size of diameter 20 microns.

16. Advantages of cyclones are
• the collected product remains dry and, normally useful.
•low capital investment and maintenance costs in most
applications.
• very compact in most applications.
• no moving parts.
• Can handle large volume of gas at high temperature
• can, in some processes, handle sticky or tacky solids with
proper liquid irrigation.
•can separate either solids or liquid particulates; sometimes
both.

17. Some disadvantages of cyclones are
 low efficiency for particle sizes below their ‘cut-off diameter when operated under lowsolids-
loading conditions.
 usually higher pressure loss than other separator types, including bag filters and low pressuredrop
scrubbers.
 subject to erosive wear and fouling if solids being processed are abrasive or‘sticky.

18. •power stations
•spray dryers
•fluidized bed and reactor riser systems (such as catalytic crackers)
•synthetic detergent production units
•food processing plants
•crushing, separation, grinding and calcining operations in the mineral and chemical
industries
•fossil and wood-waste fired combustion units
•vacuum cleaning machines
•dust sampling equipment
•ship unloading installations
Industrial usage

19. Thank You…