Sonam Tshering
Air Pollution
CHE 203
Acknowledgement
The dedicated contributions of many individuals helped to make this project, a great success.
They provided a great support and played central roles in the completion of this project work. I
would like to be grateful to each one of them.
Mostly I would like to extend my heartfelt gratitude to the municipality of Samtse Dzongkhag,
chief library, in charge of library and IT in charge for his invaluable assistance in providing us
with all facilities and other information.
Again to some of my senior colleagues who deserve a great deal of our gratitude too, for sharing
their ideas and knowledge regarding the work which enabled me to proceed without much
difficulty. They were ever ready to listen to our pleas and to lend a helping hand to solve the
problems. They were very kind enough to help us when we got struck at one point and were
unable to proceed further. I would also like to acknowledge our colleagues of our own class for
their unprecedented cooperation and their help or support whenever we are in need of it while
doing the project.
Finally, it is our module tutor Madam Reeta Rai for giving us opportunities to do assignment on
the case study of air pollution in our locality (i.e. Samtse) .This is because it becomes the hot
burning issue all over the world and moreover the government are much concerned about it .
Without this assignment we might have faced numerous difficulties to know it causes, prevention
and some tips to reduce the effect for future generation.
BE 102102
Page 1
Sonam Tshering
Air Pollution
CHE 203
Introduction
Many of us wish for going out for breath of fresh air, but many of us does not realize that this has
become irrelevant in today’s world, because the quality of air in our surrounding is anything but
fresh. The quality of fresh air is decreasing by the passage of every second due to the natural
phenomena such as eruption of volcanoes and the damaging effects by the ignoring inhabitants
of this beautiful earth.
As soon as we go out of the house and are on the road we can see the air getting polluted, a cloud
of smoke from the exhaust of vehicles such as bus, car, or a scooter, smoke coming out from a
factory chimney, fly ash generated by the thermal power plants, and speeding cars causing dust
to rise from the roads. Natural phenomena such as the eruption of volcanoes and even some
people smoking a cigarette can also cause air pollution.
Air pollution is the introduction of the chemicals, particulate matter, or biological materials that
cause harm or discomfort to humans or other living organisms, or damages the natural
environment, into the atmosphere. The atmosphere is a complex, dynamic natural gaseous
system that is essential to support life on planet earth. Stratosphere ozone depletion due to air
pollution has long been recognized as a threat to human health as well as to the earth’s
ecosystems. Pollutants can be in the form of solids particles, liquids droplets or gases. In addition
they may be natural or man-made.
It is global concern that the air pollution causes many dangerous and incurable diseases related to
respiratory system such as mal functioning and disorder of the lungs, lungs cancers, heart
diseases, bronchi cancers etc. Though the effects of air pollution are immeasurable, still there are
many methods to reduce and control the air pollution such as planting of tress, efficient use of
natural resources etc.
The details case study of air pollution in our locality such as the sources of pollutants, major air
pollutants, different types of air pollution, health impacts, some preventions and controls of air
pollution, measures under taken by the public and different sectors to reduce the air pollution are
clearly discussed in this assignment.
BE 102102
Page 2
Sonam Tshering
Air Pollution
CHE 203
What is air pollution?
Air pollution is defined as ‘The presence of one or more contaminants in the atmosphere in such
quality and for such duration as are injuries, or tends to be injuries
to health or welfare, animals or plant life.’ It is the contamination of
air by the release of harmful substances. Air pollution can cause
health problems and it can also damage the environment and
property. It has caused thinning of the protective ozone layer of the
atmosphere, which is leading to climatic change.
Air and its major pollutantsRapids modernization and progress have led to the air getting more and more polluted over the
years. Industries, vehicles, increase in the population, and urbanization are some of the major
factors responsible for air pollution in our locality. The following industries are among those that
emit a great deal of pollutants in the air in our locality: thermal power plants, bakery, Army
Welfare project, geology and mines.
Air pollution results from a variety of causes, not all of which are
within human control. Dust storms in barren areas and smoke from
forest fires and grass fire contribute to chemical and particularly to the
pollution of the air. It is not necessary that the particular locality should
affect by the pollution made by them but effect was also caused by
others. The source of pollution may be in one country but the impact of
pollution may be felt elsewhere. So our locality also feels the impact of
pollution made by India such as fly ash. Air pollution in our locality
has drastically increased because of four major developments:
increasing traffic, growing cities, rapid economic development and
industrialization. Today, the pollution in air has gradually becomes a global problem.
BE 102102
Page 3
Sonam Tshering
Air Pollution
CHE 203
The gases composition of unpolluted airThe gases
Parts per million (Vol.)
Nitrogen
756,500
Oxygen
202,900
Water
31,200
Argon
9,000
Carbon dioxide
305
Neon
17.4
Helium
5.0
Methane
0.97-1.16
Krypton
0.97
Nitrous oxide
0.49
Hydrogen
0.49
Xenon
0.08
Organic vapours
0.02
Majors air pollutants in Samtse and their impactsCarbon monoxide (CO) is a courless, odourless gas that is produced by the incomplete burning
of carbon-based fuels including petrol’s, diesel, and wood. It
is also produced from the combustion of natural and
synthetic products such as cigarettes. It lowers the amount
of oxygen that enters our blood. It can slow our reflexes and
make us confused and drowsy.
Carbon dioxide (CO2) is the principle greenhouse gas
emitted as a result of human activities such as the burning of
coal, oils and natural gases.
BE 102102
Page 4
Sonam Tshering
Air Pollution
CHE 203
Chlorofluorocarbons (CFC) are gases that are released mainly from air-conditioning systems
and refrigeration. When released into the air, CFCs rise into the
atmosphere, where they come in contact with few other gases,
while lead to a thinning of the ozone layers that protects the earth
from the harmful ultraviolet rays of the sun.
Lead (Pb) is present in petrol, diesel, lead batteries, paints, hair
dye products, etc. Lead affects children in a particular. It can
cause damage in nervous system and digestive problems and, in
some cases, causes cancer.
Ozone occurs naturally in the upper layers of the atmosphere. This important gas shields or
protects the earth from the harmful ultraviolet rays of the sun. However, at the ground level, it is
a pollutant with highly toxic effects. Vehicles and industries are the major source of ground-level
ozone emissions. Ozone makes our eyes itch, burn, and water. It lowers our resistance to colds
and pneumonia.
Nitrogen oxide (NO) causes smog and acid rain. It is produced from burning fuels including
petrol, diesel, and coal. Nitrogen oxides can make children prone to respiratory diseases in
winters.
Suspended particulate matter (SPM) consists of solids in the air in the form of smoke, dust,
vapour that can remain suspended for extended periods and is also the main source of haze which
reduces visibility. The finer of these particles, when breathed in can lodge in our lungs and cause
damage and respiratory problems.
Sulphur dioxide (SO 2) is a gas produced from burning coal, mainly in thermal power plants.
Some industrial processes, such as production of paper and smelting of metals, produce sulphur
dioxide. It is a major contributor to smog and acid rain. Sulphur dioxide can lead to lungs
diseases.
Smog is the conditions of fog that had soot or smoke in it. Smog is a combination of different
gases with water vapour and dust. A large part of the gases that form smog is produced when
fuels are burnt. Smog forms when heat and sunlight react with these gases and fine particles in
BE 102102
Page 5
Sonam Tshering
Air Pollution
CHE 203
the air. Smog can affect outlying environments and rural areas as well as big cities. It
occurrences are often linked to heavy traffic, high temperatures, and calm winds. During the
winter, wind speeds are low and cause the smoke and fog to stagnate; hence pollution levels can
increase near ground level. This keeps the pollution close to the ground, right where people are
breathing. It hampers visibility and harms the environment. Heavy smog greatly decreases
ultraviolet radiation. In fact the word smog has been coined from a combination of the words fog
and smoke. Smog refers to foggy air that causes difficult in breathing conditions.
Ground-level ozone is formed through a complex reaction involving hydrocarbons, nitrogen
oxides, and sunlight. Ground level ozone is especially harmful for seniors, children, asthmatics,
and people with heart and lung conditions. It aggravates respiratory symptoms and further
impairs the ability of these individuals to perform normal activities. It can inflame breathing
passages, decreasing the lung’s working capacity, and causing the shortness of the breath, pain
when inhaling deeply, wheezing and coughing. It can cause eye and nose irritation and dry out
the protective membranes of the nose and throat and interfere with the body’s ability to fight
infection, increasing susceptibility to illness.
Fly ash is the minute particles of ash produced from thermal power generation such as through
coal combustion and that causes serous environmental problems. Since our locality is near to the
border of India we also get affected by the fly ash in air pollution. These ash particles consists of
silica, alumina, oxides of iron, calcium, magnesium and toxic heavy
metals like lead, arsenic, cobalt, and copper. Being very minute, fly
ash tends to remain air born for very long period leading to serious
health problems as the airborne ash can enter the body. It causes
irritation to eyes, skin, nose, throat and respiratory tract. Repeated
inhalation of fly ash dust containing crystalline silica can cause
bronchitis and lung cancer.
Sources of air pollutants in our localityThe two main sources of air pollutants in our areas are transportation especially automobiles, and
fuel combustion in stationary sources, including residential, commercial, and industrial heating
and cooling and coal-burning power plants. Motor vehicles produce high levels of carbon
BE 102102
Page 6
Sonam Tshering
Air Pollution
CHE 203
monoxides and a major source of hydrocarbons and nitrogen oxides. Where as, fuel combustion
in stationary sources is the dominant source of sulphur dioxide.
Carbon dioxide is one of the major pollutants in the atmosphere. Major sources of carbon
dioxide are fossils fuels burning and deforestation. Carbon dioxide is a good transmitter of
sunlight, but partially restricts infrared radiation going back from the earth during the night.
Increasing the amount of carbon dioxides in the atmosphere reinforces this effect and is expected
to results in a warming of the earth’s surface. Currently carbon dioxide is responsible for 57% of
the global warming tendency.
Nitric oxides and nitrogen dioxide are natural component of the earth’s atmosphere. They are
important in the formation of both acid precipitation and photochemical smog (ozone), and
causes nitrogen loading. They come from the burning of biomass and fossils fuels. They have a
role in reducing stratospheric ozone.
Nitrous oxide is also natural component of the earth’s atmosphere. It is important in the
greenhouses effect and causes nitrogen. It comes from nitrogen based fertilizers, deforestation
and biomass burning.
Sulphur dioxide is produced by combustion of sulphur-containing fuels, such as coal and fuel
oils. Also, in process of producing sulphuric acids and in
metallurgical process involving ores that contains sulphur.
Sulphur dioxide can injure man, plants and materials. At
sufficiently high concentrations, sulphur dioxide irritates the
upper respiratory tract of human beings because potential
effect of sulphur dioxide is to make breathing more difficult
by causing the finer air tubes of the lung to constrict.
Chlorofluorocarbons (CFCs) are lowering the average concentration of ozone in the
stratosphere. Chlorofluorocarbons move up to the stratosphere gradually over several decades.
Under high energy ultraviolet (UV) radiation, they break down and release chlorine atoms,
which speed up the breakdown of ozone of into oxygen gas.
BE 102102
Page 7
Sonam Tshering
Air Pollution
CHE 203
Chlorofluorocarbons, also known as Freon, are greenhouse gases that contribute to global
warming. Photochemical air pollution is commonly referred to as “smog”. Smog, a contraction
of the words smoke and fog, has been caused throughout recorded history by water condensing
on smoke particles, usually from burning coal.
Smog is created by burning coal and heavy oil that contain sulphur impurities in power plants,
industrial plants, etc. The smog consists mostly of mixture of
sulphur dioxide and fog. Suspended droplets of sulphuric acid
are formed from some of the sulphur dioxide, and a variety of
suspended solid particles.
Air pollutants can be classified into primary and secondary pollutants. Usually, primary
pollutants are substances directly emitted from a process, such as ash from a volcanic eruption,
the carbon monoxide gas from a motor vehicle exhaust or sulphur dioxide released from
factories. Secondary pollutants are not emitted directly, rather they form in the air when primary
pollutants react or interact.
BE 102102
Page 8
Sonam Tshering
Air Pollution
CHE 203
Major primary pollutants produced by human activity include:

Sulphur oxides, a chemical compound with the formula SO 2 produced by volcanoes and
various industrial processes. Since coal and petroleum often contain sulphur compound,
their combustion generates sulphur dioxide. Further oxidation of SO2 usually in the
presence of catalyst such as nitrogen dioxide, forms H2 SO4) , and thus acid rain. This is
one of the causes for the concern over the environmental impact of the uses of these fuels
as power sources.

Nitrogen oxides (NO2 ) are emitted from high temperature combustion. This reddishbrown toxic has a characteristic sharp, biting odor. NO2 is one of the most prominent air
pollutants.

Carbon monoxide: is a colourless, odourless, non-irritating but very poisonous gas. It is
a product by incomplete combustion of fuel such as natural gas, coal or wood. Vehicles
exhaust is a major source of carbon monoxide.

Carbon dioxide: a green house gas emitted from combustion but is also from a gas vital
to living organisms. It is a natural gas in atmosphere.

Volatile organic compounds are an important out door air pollutant. In this field they are
often divided into the separate categories of methane (CH4) and non-methane. Methane is
an extremely efficient green house gas which contributes to enhance global warming.
Within the non-methane, the aromatic compounds benzene, toluene and xylene are
suspected carcinogens and may lead to leukemia through prolong exposure. 1, 3butadiene is another dangerous compound which is often associated with industrial uses.

Particulate matter (PM) or fine particles are tiny particles of solid or liquid suspended
in a gas. In contrast, aerosol refers to particles and the gas together. Sources of particulate
matter can be man made or natural. 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 the fossils fuels in vehicles, power plants and
various industrial processes also generates significant amounts of aerosols. Increased
levels of fine particles in the air are linked to health hazards such as heart disease, altered
lung function and lung cancer.
BE 102102
Page 9
Sonam Tshering
Air Pollution
CHE 203

Toxic metals such as lead, cadmium and copper.

Chlorofluorocarbons (CFCs) are harmful to ozone layer emitted from products
currently banned from use.

Ammonia (NH3) is emitted from agricultural processes. It is normally encountered as a
gas with a characteristics pungent odour. Ammonia contributes significantly to the
nutritional needs of terrestrial organisms by serving as a precursor to foodstuffs and
fertilizers. Although in wide use, ammonia is both caustic and hazardous.

Odours: such as from garbage, sewage, and industrial processes.

Radioactive pollutants: produced by nuclear explosions, war explosion, and natural
processes such as the radioactive decay of radon.
Secondary pollutants include:
 Particulate matter formed from gaseous primary pollutants and compounds in
photochemical smog. Classic smog results from large amounts of coal burning in an area
caused a mixture of smoke and sulphur dioxide. Modern smog does not usually come
from coal but from vehicles and industrial emission that are acted on in atmosphere by
sunlight to form secondary pollutants that also combines with the primary emissions to
form photochemical smog.
 Ground level ozone (O3) is a key constituent of the troposphere and it is also an
important constituent of certain regions of the stratosphere and 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.
 Peroxyacetyl nitrate (PAN): similarly formed from non-methane and volatile carbons.
BE 102102
Page 10
Sonam Tshering
Air Pollution
CHE 203
The sources of air pollution can be also classified into two major categories;
Anthropogenic sources (human activity) mostly related to burning different kind of fuel;
 Stationary sources include smoke
stacks of power plant, manufacturing
factories and waste incinerators, as well
as furnaces and other types of fuel
burning heating devices.
 Mobile sources include motor vehicles,
marine vessels, aircraft and the effect
of sound etc...
 Chemicals, dust and controlled burn
practices in agriculture and forestry
management. Controlled or prescribed
burning is a technique sometimes used
in management, farming, prairie
restoration or green house gas abatement. Fire is a natural part of both forest and
grassland ecology and controlled fire can be a tool for foresters. Controlled burning
stimulates the germination of some desirable forest tress, thus renewing the forest.
 Fumes from paint, hair spray, varnish, aerosol sprays and other solvents.
 Waste deposition in landfills, which generate methane. Methane is not toxic; however it
is highly flammable and may form explosive mixtures with air. Methane is also an
asphyxiant and may display oxygen in an enclosed space. Asphyxia or suffocation may
result if the oxygen concentration is reduced to below 19.5% by displacement.
 Military such as nuclear weapons, toxic gases, germ warfare and rocketry.
Natural sources:
 Dust from natural sources, usually large areas of land with little or no vegetation.
 Methane emitted by the digestion of food by animals, for example cattle.
 Radon gas from radioactivity decay within the earth crust. Radon is a colourless,
odourless, naturally occurring radioactive noble gas that is formed from the decay of
BE 102102
Page 11
Sonam Tshering
Air Pollution
CHE 203
radium. It is considered to be health hazard and is the second most frequent causes of
lung cancer, after cigarette smoking.
 Smoke and carbon monoxide from wild fires.
 Volcanic activity, which produce sulphur, chlorine and ash particulates.
Common atmospheric pollution sources and their pollutants in Samtse:
Category
Source
Emitting pollutants
Suspended particulate matter,
Agriculture
Open burning
carbon monoxide, volatile
organic compounds.
Suspended particulate matter,
Mining and quarrying
Coal mining: crude oil and gas
sulphur dioxide, oxide of
production; stone quarrying.
nitrogen, volatile organic
compounds.
Suspended particulate matter,
sulphur dioxide, oxides of
Power generation
Electricity; gas ; steam
nitrogen, carbon monoxide,
volatile organic compounds,
lead.
Suspended particulate matter,
sulphur dioxide, oxides of
Community service
Municipal incinerators.
nitrogen, carbon monoxide,
volatile organic compounds,
lead.
BE 102102
Page 12
Sonam Tshering
Air Pollution
CHE 203
Health impacts of air pollution
Since the onset of the industrial revolution, there has been a steady change in the composition of
the atmosphere mainly due to the combustion of fossil fuels used for the generation of energy
and transportation. Air pollution is a major environment health problem affecting the developing
and the developed countries alike. The effects of air pollution on health are very complex as
there are many different sources and their individual effects vary from one to another. It is not
only the ambient air quality in the cities but also the indoor air quality in rural and the urban
areas that are causing concern. In fact in the developing world the highest air pollution exposure
occur in the indoor environment. Air pollutants that are inhaled have serious impact on human
health affecting the lungs and the respiratory system; they are taken up by the blood and pumped
all round the body. These pollutants are also deposited on soil, plant and in the water, further
contributing to human exposure.
Indoor air pollution can be particularly hazardous to health as it is released in close proximity to
people. It is stated that a pollutant released indoors is many times more likely to reach the lung
than that are released outdoors. A fairly large portion of the population is dependent on biomass
for their energy requirements including wood, charcoal, agriculture residue, and animal waste.
Open fires used for cooking and heating are commonly found in the household both in the rural
and the urban areas. The stove is often at floor level, adding to the risk of accident and the
hygiene factor. In addition, they are often not fitted with a chimney to remove the pollutants. In
such households the children and women are most likely to be affected, as they are the group that
spends more times indoors. Many of the deaths are due to acute respiratory infections in
children; other is due to cardiovascular diseases, lung cancer and chronic respiratory diseases in
adults. If emissions are high and ventilation is poor, household use of coal and biomass can
severely affect the indoor air quality.
The most harmful of the pollutants that are emitted are particulate matter, carbon dioxide,
polycyclic organic matter and formaldehyde. Some of these gases can seriously and adversely
affect the health of the population and should be given due attention by the concerned authority.
The gases mentioned below are mainly outdoor air pollutants but some of them can occur indoor
depending on the source and the circumstances.
BE 102102
Page 13
Sonam Tshering
Air Pollution
CHE 203
 Tobacco smoke: it generates a wide range of harmful chemicals and is a major cause of
ill health, as it is known to cause cancer, not only to the smoker but affecting passive
smokers too. It is well-known that smoking affects the passive smoker ranging from
burning sensation in the eyes or nose, throat irritation, severe asthma and decrease in lung
function.
 Biological pollutants: these are mostly allergens that can cause asthma, hay fever and
other allergic diseases.
 Volatile organic compounds: these can cause irritation of the eye, nose and throat. In
severe cases there may be headaches, nausea and loss of co-ordination. In the longer run,
some of them are suspected to cause damage to the liver and other parts of the body.
 Formaldehyde: exposure to formaldehyde causes irritation to the eyes, nose and may
cause allergies in some people.
 Lead: prolong exposure can cause damage to the nervous system, digestive problems and
in some cases cause cancer. It is especially hazardous to small children.
 Radon: a radioactive gas that can accumulate inside the house, it originates from the
rocks and soil under the house and its level is dominated by the outdoor air and also to
some extent the other gases being emitted indoors. Exposure to this gas increases the risk
of lung cancer.
 Ozone: exposure to this gas makes our eyes itch, burn and watery and it has also been
associated with increase in respiratory disorders such as asthma. It lowers our resistance
to colds and pneumonia.
 Oxides of nitrogen: this gas can make children susceptible to respiratory diseases in the
winter.
 Carbon monoxides: these combines with haemoglobin to lessen the amount of oxygen
that enters our blood through our lungs. The binding with other haeme proteins causes
changes in the function of the affected organs such as the brain and the cardiovascular
system and also the developing fetus. It can impair our concentration, slow our reflexes
and make us confused and sleepy.
 Sulphur dioxide: it is caused due to the rise in combustion of fossil fuel. SO2 in the air
leads to diseases of the lung and other lung disorders such as wheezing and shortness of
BE 102102
Page 14
Sonam Tshering
Air Pollution
CHE 203
breath. Long term effects are more difficult to ascertain as sulphur dioxide exposure is
often combined with that of SPM.
 SPM (suspended particulate matter): it consists of dust, fumes, mist and smoke. The
main chemical component of SPM that is of major concern is lead, other is nickel, arsenic
and those present in diesel exhaust. These particles when breathed in, lodge in our lung
tissues and causes damage and respiratory problems.
Air pollution prevention and control:
Pollution prevention and control is a system of rules which controls what certain industries have
to do to prevent air pollution, or a set of rules and regulations for controlling pollution from
industries which have been the potential to harm the environment.
How can we prevent the damaging effects of air pollution?
In many countries in the world, steps are being taken to stops the damage to our environment
from air pollution. Scientific groups study the damaging effects on plants, animals and human
life. Legislative bodies write laws to control emissions. Educators in schools and universities
teach students, beginning at very young ages about the effects of air pollution.
Prevention is another key to controlling air pollution. The regulatory agencies mentioned above
play an essential role in reducing and preventing air pollution in the environment. In addition, it
is possible to prevent many types of air pollution that are not regulated through personal, careful
attention to our interactions with the environment. Adequate ventilation is also a key to
controlling exposure to indoor air pollution. Home and work environments should be monitored
for adequate air flow and proper exhaust system installed.
One of the most dangerous air pollutants is cigarette smoke. Restricting smoking is an important
key to a healthier environment. Legislation to control smoking is in effect in some location, but
personal exposure should be monitored and limited wherever possible.
Only through the effects of scientists. business leader, legislators and individuals can we reduce
the amount of air pollution on the plant. This challenge must be met by all of us in order to
assure that a healthy environment will exist for our self and our children.
BE 102102
Page 15
Sonam Tshering
Air Pollution
CHE 203
Some methods of reducing air pollution:
Earth is every body’s home and nobody likes living in a dirty home. Together, we can make the
earth a cleaner, healthier and, more pleasant place to live. There are many ways to reduce air
pollution. Some of the measures are as follows:

Encouraging our family to walk to the neighborhoods market instead of travelling in a
car.

If possible use bicycle instead of car.

As far as possible use public form of transport.

Encourage our family to a car pool to office and back.

Reduce the use of aerosols in the household.

Look after the tress in our neighborhoods.

Begin a trees-watch group to ensure that we are well tented and cared fro.

Switch off all the lights and fans when not required.

If possible share our room with others when the air conditioner, cooler or fan is on.

Do not burn leaves in our garden; put them in compost pit.

Make sure that the pollution check for our family car is done at regular intervals.

Cars should as far as possible, be fitted with catalytic converters.

Use only unleaded petrol.

Make public aware of the hazardous affect of the air pollution.

Be the role model such as by planting the tress etc…
BE 102102
Page 16
Sonam Tshering
Air Pollution
CHE 203
Air pollution control in Samtse:
Particulate control;

Mechanical collectors (dust cyclones, multicyclones).

Electrostatic precipitators are particulate collection devices that are removes particles
from a flowing gas using the force of an induced electrostatic charge. Electrostatic
precipitators are highly efficient filtration devices that minimally impede the flow of
gases through the device, and can easily remove fine particulate matter such as dust and
smoke from the air stream.

Bag house is a designed to handle heavy dust loads, a dust collector consist of a blower,
dust filter- cleaning system and a dust receptacle or dust removal system.

Particulate scrubbers are a form of pollution control technology. The term describes a
variety of devices that use pollutants from a furnace flue gas or from other gas streams. In
a wet scrubber, the pollutants gas stream is brought into contact with the scrubbing
liquids, by spraying it with the liquid, by forcing it through a pool of liquid, or by some
other contact method, so as to remove the pollutants.
Scrubbers:

Baffle spray scrubber.

Cyclonic spray scrubber.

Ejector venture scrubber.

Mechanically aided scrubber.

Spray tower.
NOx control:

Low Nox burners.

Selected catalytic reduction.

Selected non-catalytic reduction.

Exhaust gas recirculation.

Catalytic converter.
BE 102102
Page 17
Sonam Tshering
Air Pollution
CHE 203
VOC abatement:

Wet scrubber.

Adsorption system. Such as activated carbon.

Flares.

Thermal oxidizer.

Catalytic oxidizers.

Biofilters.

Absorption.

Cryogenic condensers.

Vapour recovery system.
Acid gas control (SO2):
 Wet scrubbers.
 Dry scrubber.
 Flue gas desulphurization.
Mercury control:
 Sorbent injection technology.
 Electro-catalytic oxidation.
 K- Fuel.
Miscellaneous associated equipment:
 Source capturing system.
 Continuous emission monitoring systems.
BE 102102
Page 18
Sonam Tshering
Air Pollution
CHE 203
Prevention measures undertaken by different sectors in Samtse:
 Dzongkhag administration makes the public aware of the impacts caused by the air
pollution for their healthier life.
 Samtse municipality makes the public services such as by collecting and dumping of
waste materials instead of burning them.
 Samtse General Hospital also makes people aware of the air pollution in response to
some diseases detected by the medical officers.
BE 102102
Page 19
Sonam Tshering
Air Pollution
CHE 203
Conclusion:
Air pollution can be defined as the presence of harmful substances in the atmosphere in any
quantity for any duration that is injuries to the environments, animals’ health and the well being
of the humans. And those substances in atmosphere which are injuries to welfare or animals,
human and plant life are called as the air pollutants. I came to know that there are many sources
of air pollutants which are naturals as well as the man made. The natural sources occur through
the natural phenomenon such as the eruptions of volcanoes etc, while the man made sources
occurs mainly due to the rapid modernizations and industrialization etc.
The major pollutants includes the harmful substances such as carbon monoxide, carbon dioxide,
sulphur dioxide , nitrous oxide, particulate matter, ammonia, nitrogen oxides, volatile organic
compounds, ground level ozone, some toxic metals such as lead and many more. After doing this
assignment I came to know there are many diseases caused by the air pollution both in the adults
and young one’s such as heart diseases, lung cancer, malfunctioning of the lungs, asthma etc…
Though this pollution in air are from natural and man-made, it is for sure that the pollutants in
the air can be reduced and controlled. There are many different ways of reducing air pollution. A
forestation or planting of tress is the major role to reduce pollution in air. Through planting trees
the cool and fresh oxygen gas can be manufactured and the harmful gas such as carbon- dioxides
and carbon monoxides can be reduced to certain extent.
We as the inhabitants of this beautiful home, Earth, the sole of responsibilities lie in the hands of
every individual to choose whether we want to live in the dirty home or in cleaner home. Of
many ways to reducing air pollution we can practice at least one such as planting of trees and
taking care of it, not burning the waste materials etc.
Lastly I can say that 90% of air pollution is man made and there are nothing to be worried about
because we as a superior animal have power of differentiating what is good and what is
hazardous. So air pollution being the hazardous and injurious to welfare of human health we can
take the preventive measures to reduce pollution in air and make our atmosphere a clean and
natural fresh air to be breathed and enjoy the natural fresh air.
BE 102102
Page 20
Sonam Tshering
Air Pollution
CHE 203
References:
Dzongkahg Municipality Organization in Samtse.
Retrieved on April 23, 2011 from http://en.wikipedia.org/wiki.Air-pollution.
Retrieved on April 15, 2011 from http://www.epa.gov/ebtpages/air.htm//.
Retrieved on May 10, 2011 from http://edugreen.teri.res.in/explore/air/airintro.htm//.
Retrieved on May 15, 2011 from http:// healthhandenergy.com/air-pollution-causes.htm//
Retrieved on May 20, 2011 from http:// edugreen.teri.res.in/explore/air/health.htm/
Retrieved on May 20, 2011 from http://www.imo.org/environment/ mainframe.asp?topicMainframe.asp? Topic-id=233
Retrieved on May 25, 2011 from http:// www.lbl.gov/education/ELSI/Frames/
Pollution-prevention-f.html
BE 102102
Page 21