2. • Air is essential for life it self, without it we could
survive only a few minutes.
• It constitutes immediate physical environment of
living organisms.
• The atmosphere is layered in to four distinct
which are: Troposphere, stratosphere,
mesosphere, and thermosphere.
INTRODUCTION
5. • Air pollution refers to any physical , chemical or
biological change in the air.
• It is contamination of air by harmful gases, dust
& smoke which affects the plants , animals &
humans drastically.
• There is certain percentage of gases present in
the atmosphere.
AIR POLLUTION
6. • An increase or decrease in the composition of
these gases is harmful to survival.
• This imbalance in the gaseous composition has
resulted in an increase in Earth’s temperature
which is known as GLOBAL WARMING.
7. • Air pollutants are natural & artificial airborne
substances that are introduced into the
environment in a concentration sufficient to
have measurable effect on humans , animals,
vegetation, or building materials.
• Air pollutants may be either emitted into the
atmosphere or formed within atmosphere itself.
AIR POLLUTANTS
10. SULPHUR OXIDES (SOx)
• SO2 is produced by volcanoes and in various
industrial processes.
• Since coal and petroleum often contain sulphur
compounds, their combustion generates sulphur
dioxide.
• Further oxidation of SO2, usually in the presence
of a catalyst such as NO2, forms H2SO4, and thus
acid rain.
• This is one of the causes for concern over the
environmental impact of the use of these fuels as
power sources.
11. NITROGEN OXIDES (NOx)
• Especially nitrogen dioxide are emitted from
high temperature combustion.
• Nitrogen dioxide is the chemical compound
with the formula N02.
• It is responsible for photochemical smog, acid
rain etc.
16. CARBON MONOXIDE
• It is a colourless, odourless, non-irritating but
very poisonous gas.
• It is a produce by incomplete combustion of
fuel such as natural gas, coal or wood.
• Vehicular exhaust is a major source of carbon
monoxide.
17. CARBON DIOXIDE (CO2)
• A greenhouse gas emitted from combustion
but is also a gas vital to living organisms.
• It is a natural gas in the atmosphere.
19. SMOG
• Particulate matter formed
from gaseous primary
pollutants and compounds in
photochemical smog. Smog is
a kind of air pollution.
• Classic smog results from large
amounts of coal burning in an
area caused by a mixture of
smoke and sulphur dioxide.
• Modern smog does not usually
come from coal but from
vehicular and industrial
emissions that are acted on in
the atmosphere by sunlight to
form secondary pollutants .
20. PARTICULATE MATTER
• Some particulates occur naturally, originating
from volcanoes, dust storms, forest and
grassland fires, living vegetation, and sea spray.
• Human activities, such as the burning of fossil
fuels in vehicles, power plants and various
industrial processes also generate significant
amounts of aerosols.
21. GROUND LEVEL OZONE(O3)
• Ground level ozone (O3) formed from NOx and
VOCs.
• Ozone (O3) is a key constituent of the troposphere
(it is also an important constituent of certain regions
of the stratosphere commonly known as the Ozone
layer).
• Photochemical and chemical reactions involving it
drive many of the chemical processes that occur in
the atmosphere by day and by night.
• At abnormally high concentrations brought about by
human activities (largely the combustion of fossil
fuel), it is a pollutant, and a constituent of smog.
22. • Particulate matter is a mix of solids and liquids,
including carbon, complex organic chemicals,
sulphates , nitrates, mineral dust, and water
suspended in the air.
• PM varies in size.
• Some particles, such as dust, soot, dirt or smoke
are large or dark enough to be seen with the naked
eye.
• But the most damaging particles are the smaller
particles, known as PM10 and PM2.5.
PARTICULATE
MATTER (PM)
23. • PM10 particles with a diameter smaller than
10 microns (10µm) – that’s 100 times smaller
than a millimetre.
• PM2.5 particles with a diameter smaller than
2.5 microns, and these are known as fine
particles.
• The smallest fine particles, less than 0.1 micron
in diameter, are called ultrafine particles.
25. ORIGIN
• Man-made particulate matter mainly comes from
industry, building work, diesel and petrol
engines, friction from brakes and tyres , and dust
from road surfaces.
• Diesel engines tend to produce much more than
equivalent petrol engines.
26. • Natural sources of particulate matter include
volcanoes, sea spray, pollen and soil.
• It is also formed in the atmosphere when
gases such as nitrogen dioxide and sulphur
dioxide are changed in the air by chemical
reactions.
27. How does PM affect your lungs?
• The size of particulate matter will determine
where it will end up once you breathe it in.
• Larger particles may be trapped in your nose,
while PM10 can reach your airways.
• Fine particles (PM2.5) may reach the breathing
sacs deep in your lungs, and ultrafine particles
may even cross into your blood stream.
• These particles can also carry toxic chemicals
that are linked to cancer.
28. How does PM affect your lungs?
• Particulate matter irritates your nose and throat
and may be associated with more severe
symptoms in people with asthma.
• It results in more people with lung conditions
(COPD, asthma, bronchitis) and heart conditions
(heart attacks, strokes) being admitted to
hospital.
• It also causes early deaths from lung and heart
disease.
29.
30. NITROGEN DIOXIDE (NO2)
1. What is nitrogen dioxide (NO2)?
Nitrogen dioxide is a gas and is a major
component of urban air pollution episodes.
2. Where does NO2 come from?
• Vehicles, power stations and heating.
• Diesel vehicles are major contributors in
urban areas.
31. 3. How does NO2 affect your lungs?
• High levels of NO2 can irritate and inflame the
lining of your airways, causing a flare-up of
asthma or COPD and symptoms such as
coughing and difficulty breathing.
• Respiratory infection and may react more to
allergens (any substance that triggers an allergic
reaction, such as pollen).
32. OZONE (O3)
1. What is ozone?
Ozone is a gas composed of 3 atoms of oxygen. In the
upper level of the Earth’s atmosphere, it absorbs
harmful ultraviolet radiation.
2. Where does ozone come from?
• Near the ground, ozone is made by a chemical
reaction between the sun’s rays and organic gases and
oxides of nitrogen emitted by cars, power plants,
chemical plants and other sources.
• Ozone is usually highest in the spring and summer
and lowest in the winter.
• Ozone levels are highest during the afternoon and are
often higher in the country than in towns.
33. 3. How does ozone affect your lungs?
• Ozone can irritate the airways of both healthy people
and those with lung conditions.
• High levels can cause discomfort when you breathe,
reduce your lung capacity (the amount of air your
lungs can hold) and trigger asthma symptoms.
• If you have a lung condition, high levels of ozone can
cause difficulty breathing, wheezing and coughing.
• People with asthma may need to use their reliever
inhaler more often.
34. SULPHUR DIOXIDE(SO2)
1. What is sulphur dioxide?
Sulphur dioxide is a colourless gas, with a pungent,
suffocating smell. It’s produced by burning
sulphur-containing fuels such as coal and oil. This
includes vehicles, power generation and heating.
2. Where does sulphur dioxide come from?
Most sulphur dioxide comes from electric industries
that burn fossil fuels, and also from petrol refineries
and cement manufacturing. It can travel over long
distances and contributes to the formation of ozone.
35. 3. How does sulphur dioxide affect your lungs?
• Sulphur dioxide can irritate the lining of your nose,
throat and lungs.
• It can cause coughing and tightness of your chest, as
well as a narrowing of your airway that will reduce the
flow of air to your lungs.
• It inflames the airways, causing coughing and more
mucus.
• It makes conditions like asthma and COPD worse and
can lead to people being more prone to chest
infections.
• People with asthma are much more sensitive to
sulphur dioxide than those who do not have asthma.
• They may find breathing more difficult and have flare-
ups when concentrations of sulphur dioxide are high.
37. POINT SOURCE
• A point source is a single, identifiable source of
air pollutant emissions (for example, the
emissions from a combustion furnace flue gas
stack).
• Point sources are also characterized as being
either elevated or at ground-level. A point
source has no geometric dimensions.
38. LINE & AREA SOURCES
• A line source is one-dimensional source of air
pollutant emissions (for example, the emissions
from the vehicular traffic on a roadway).
• An area source is a two-dimensional source of
diffuse air pollutant emissions (for example, the
emissions from a forest fire, a landfill or the
evaporated vapors from a large spill of volatile
liquid).
39. VOLUME SOURCE
• A volume source is a three-dimensional source of
diffuse air pollutant emissions.
• Essentially, it is an area source with a third (height)
dimension (for example, the fugitive gaseous
emissions from piping flanges and other equipment
at various heights within industrial facilities such as
petroleum refineries and petrochemical plants.
• Another example would be the emissions from an
automobile paint shop with multiple roof vents or
multiple open windows.
CON.......
40. OTHER POLLUTANT SOURCES
• Sources may be characterized as either stationary
or mobile. Flue gas stacks are examples of
stationary sources and automobiles are examples of
mobile sources.
• Sources may be characterized as either urban or
rural because urban areas constitute a so-called
''heat island'' and the heat rising from an urban
area causes the atmosphere above an urban area to
be more turbulent than the atmosphere above a
rural area.
CON..............
41. • Sources may be characterized by their elevation
relative to the ground as either surface or
ground-level, near surface or elevated sources.
• Sources may also be characterized by their time
duration :
Short term sources (for example, many
accidental emission)
43. THE CENTRAL POLLUTION CONTROL
BOARD (CPCB)
• It is an autonomous body under the Ministry of
Environment, Forest and Climate Change (MoEF&CC).
It was established in 1974 under the Water
(Prevention and Control of Pollution) Act, 1974.
• It co-ordinates along with the activities of SPCB’s (State
Pollution Control Board) and PCC’s (Pollution Control
Comittees). These three comittees are responsible for
implementing the legislations related to Prevention
and Control of Pollution .
•It also advises the Governments of Union Territories on
industrial and other sources of water and air pollution.
44. • The CPCB is responsible for implementation of
legislation relating to prevention and control of
environmental pollution.
• The CPCB also advises the Central Govt. on all
matters concerned to the Prevention and Control
of Pollution and provides technical assistance to
the Ministry of Environment .
• The mandate of the CPCB under Air Act
empowers it to set standards for the air quality
and hence, Air Quality Parameters are
established.
45. • An air quality index (AQI) is a number used by
government agencies to communicate to the
public how polluted the air currently is or how
polluted it is forecast to become.
Salient features of the Index:
• The measurement of AQI is based on 8 pollutants
(CPCB) – PM 10, PM 2.5, SO2, Nox, O3, CO, NH3
and Lead.
• The unit of measurement is microgram (or
milligram in the case of CO) per cubic meter.
• The AQI has been at present launched for 10 cities
-- Delhi, Agra, Kanpur, Lucknow, Varanasi,
Faridabad, Ahmedabad, Chennai, Bangalore and
Hyderabad.
51. METHODS TO CONTROL AIR POLLUTION
• IN GENERAL:---------------
1. Conserve energy - at home, at work, everywhere.
2. Look for the ENERGY STAR label when buying home
or office equipment.
3. Carpool, use public transportation, bike, or walk
whenever possible.
4. Follow gasoline refueling instructions for efficient
vapor recovery, being careful not to spill fuel
And always tightening your gas cap securely.
5. Combine errands and reduce trips. Walk to errands when
possible.
6. Avoid excessive idling of your automobile.
7. Refuel your car in the evening when its cooler.
55. GRAVITATIONAL SETTLING CHAMBER
•This is used for the removal
of particles exceeding 50
micro meter in size .
•The gas stream polluted with
particulates are allowed to
enter from one end.
•For providing sufficient time
for the particles to settle
down the velocity of gas
stream is kept low.
• Particulates having higher
density obey STOKE’S LAW.
56. CYCLONE SEPARATORS
• Centrifugal force is utilized by
cyclone separators instead of
gravitational force.
• The dust gas enters
tangentially & generates the
centrifugal force due to which
the particulates are thrown out
of the cyclone walls.
•The particulates slide down the
walls of cone & are discharged
from the outlet.
57. ELECTROSTATIC PRECIPITATORS
• It works on a principle of
electrostatic precipitation
i.e electrically charged
particulates present in
polluted gas are separated
from the gas under the
influence of electrical field.
• Has 99% efficiency
• Can be operated at high
temperatures(600 C) at less
power .
