The document discusses various dust suppression systems used in industrial settings including spray systems, foggers, centrifugal dust collectors, and electrostatic precipitators. It provides details on the operation and components of each type of system as well as factors to consider like efficiency, cost, and impact on product quality. References are also included that provide additional information on controlling respirable dust.

2. 1)Present Day Dust Suppression Systems A Case Study by Prashant Mehrotra and
Mukesh Dubey G.B Technical University, Jhansi.
2)Alternate Technologies for Dust Suppression and Location by Makarand Joshi
R.G. Technical University ITM Universe, Gwalior.
3)Systems for Dust Control in Thermal Power Plant by Ankush Kumar and Sumit
Chakraborty NIT Hazratbal,Srinagar.

3. 1. Must be efficient to meet Health & Safety requirements.
2. Be practical and simple in operation.
3. Have low operating costs.
4. No adverse effects on product quality or plant and
machinery should be created.
5. The spray discharge should be proportional with dust
emission.
6. The solenoid valve should be open with proportion with
quantity of dust generation.
7.Metering pump should function effectively for detecting
chemical concentration in main water tank.

4. • Auto control or manual control
governs the system. It has to be
insured that main tank is filled
with water. The water is
pumped by feed water pump
from main tank to feed water
tank and at the same time
metering pump doses proper
quantity of chemical. The feed
water pump operation is
controlled by float switch
automatically. The pump picks
up at low level and stopped at
high level.

5. • The system is based on a very
unique device which can produce a
very dense fog of 1 - 10 micron size
water droplets which literally
blanket the dust source and keep
the dust particles from becoming
airborne.The fogger is an air driven
acoustic oscillator for fogging
liquids by passing them through a
field of high frequency sound
waves. This is accomplished by
compressing air upstream of a
specially designed converge section
of the nozzle.

6. The sound generator generates sound beam. The stainless steel reflector on
the other side reflects the sound beam. The receiver who is built with sound
generator receives the reflected sound beam. The dust particles absorb some of
the energy of sound beam and also deflect sound beam. The sound signal
received is inversely proportional to the dust emission.

10. CENTRIFUGAL DUST COLLECTOR
• Centrifugal collectors use cyclonic action to
separate dust particles from the gas stream.
• This device uses the principle of dynamic
precipitation technique in which very high
suction pressure suck the dusty air and allow
to centrifuge through it.
• The dust collector has a small tank full of
water which has two valves. These two
springs loaded valves are operated to allow
passage of concentrated dust and automatic
filling of fresh water.
• The centrifugal dust collector is highly
efficient since it uses minimum amount of
water and discharges dust in its concentrated
form.

11. • Electrostatic precipitators use electrostatic forces to separate dust
particles from exhaust gases.
• A number of high-voltage, direct-current discharge electrodes are placed
between grounded collecting electrodes. The contaminated gases flow
through the passage formed by the discharge and collecting electrodes.
• The airborne particles receive a negative charge as they pass through the
ionized field between the electrodes
• These charged particles are then attracted to a grounded or positively
charged electrode and adhere to it.
• The collected material on the electrodes is removed by rapping or
vibrating the collecting electrodes either continuously or at a
predetermined interval. Cleaning a precipitator can usually be done
without interrupting the airflow.

12. • 1. Research paper “Control of Respirable Dust” by Schowengerdt, F.D.
& Brown, J.T. in the April 1976 issue of "Coal Age Magazine".
• 2. Report No 1-800-35-NIOSH of National Institute for Occupational
Safety and Health.
• 3. Study by the Bureau of Mines' Dust Lab in Pittsburgh.
• 4. Literature by T&T Systems, Inc. Eastern Regional Office P.O. Box
1484 Bluffton, SC.29910.
• 5. Research paper “Fundamental Scattering Properties Of Respirable
Dusts And Suspended Particulate Matter” by C. D. Litton, Affiliation:
Pittsburgh Research Laboratory, National Institute for Occupational
Safety and Health 1-412-386-5167 .