1. The document discusses air pollution, defining it as the presence of harmful contaminants or combinations of contaminants in the air that can negatively impact human health, animals, plants, or property. 2. Sources of air pollution are divided into natural sources like pollen, volcanic eruptions, forest fires, and dust storms, and man-made or anthropogenic sources like emissions from industries, power plants, vehicle exhaust, and fossil fuel burning. 3. Specific examples of natural sources include descriptions of how pollen helps with plant fertilization and volcanic eruptions expel hot materials. Examples of man-made sources given are how industries and vehicle exhaust release particulates and gases, and how thermal power plants

1. GREEN UNIVERSITY OF BANGLADESH
Department Of Textile
ASSIGNMENT
Remarks:
Course Code : TE 311
Course Title : Textile Mill Utilities
Submitted By:
Name : Md Rakibul Hassan
ID : 183014057
Section : E1
Department : Textile
Date Of Performance : 30-08-2020
Date Of Submission : 02-09-2020
Assignment Topic : Air Pollution
Submitted to:
Name : Mr. Md. Al Amin Hossain
Designation : Lecturer
Department : Textile

2. Assignment On Air Pollution
Air Pollution:
Air pollution is a major problem of recent decades, which has a serious toxicological impact on human
health and the environment. The sources of pollution vary from small unit of cigarettes and natural
sources such as volcanic activities to large volume of emission from motor engines of automobiles
and industrial activities. Long-term effects of air pollution on the onset of diseases such as respiratory
infections and inflammations, cardiovascular dysfunctions, and cancer is widely accepted hence, air
pollution is linked with millions of death globally each year. A recent study has revealed the
association between male infertility and air pollution.
Definition of Air Pollution:
Air pollution defined as the of one or more contaminants or combinations in such quantities and of
such durations as may be or tend to be injurious to human, animal or plant life, or property, or which
unreasonably interferes with the comfortable enjoyment of life or property or conduct of business.
Air pollution can also be defined as an alteration of air quality that can be characterized by
measurements of chemical, biological or physical pollutants in the air. Therefore, air pollution means
the undesirable presence of impurities or the abnormal rise in the proportion of some constituents of
the atmosphere. It can be classified in 2 sections: visible and invisible air pollution.
Source Of Air Pollution:
We can divide source of air pollution into two types:
1. Natural
2. Man made or Anthropogenic
1. Natural:
a. Pollen grains
b. Volcanic eruptions
c. Forest fires
d. Dust storms
e. Spores
f. Bacteria and other microorganisms.
(a) Pollen grains:
Spring is a time of new growth and fresh beginnings. Days get longer, the sun gets warmer, and
flowers bloom in a magnificent show of color. And as a result of these lovely blossoms everywhere,
many of us find ourselves in sneezing fits. In order for flowers to propagate every year, they must be
pollinated. And pollination sends millions of tiny pollen grains through the air, many of which end
up in our nose.
But pollen does not exist simply to make us miserable. Pollen grains represent the male portion of the
reproductive process in plants and trees. These tiny bodies are swirling in the air and on the legs of
insects so that they can join the female part of the plant to create a new seed. This important process
is known as fertilization. As we will discover, pollen plays a crucial role in the plant world.
(b) Volcanic eruptions:
A volcanic eruption occurs when hot materials from the Earth's interior are thrown out of a volcano.
Lava, rocks, dust, and gas compounds are some of these "ejecta". ... Some are quiet outflows of hot
lava. Several more complex types of volcanic eruptions have been described by volcanologists.

3. (c) Forest fire:
A wildfire or wildland fire is a fire in an area of combustible vegetation occurring in rural areas.
Depending on the type of vegetation present, a wildfire can also be classified more specifically as a
brush fire, bushfire, desert fire, forest fire, grass fire, hill fire, peat fire, vegetation fire, and veld fire.
Wildfires can be characterized in terms of the cause of ignition, their physical properties, the
combustible material present, and the effect of weather on the fire . Wildfires can cause damage to
property and human life, though naturally occurring wildfires may have beneficial effects on native
vegetation, animals, and ecosystems that have evolved with fire. High-severity wildfire creates
complex early seral forest habitat (also called "snag forest habitat"), which often has higher species
richness and diversity than unburned old forest. Many plant species depend on the effects of fire for
growth and reproduction. Wildfires in ecosystems where wildfire is uncommon or where non-native
vegetation has encroached may have strongly negative ecological effects. Wildfire behavior and
severity result from the combination of factors such as available fuels, physical setting, and weather.
Analyses of historical meteorological data and national fire records in western North America show
the primacy of climate in driving large regional fires via wet periods that create substantial fuels or
drought and warming that extend conducive fire weather.
(d) Dust Storms:
A dust storm, also called sandstorm, is a meteorological phenomenon common in arid and semi-arid
regions. Dust storms arise when a gust front or other strong wind blows loose sand and dirt from a
dry surface. Fine particles are transported by saltation and suspension, a process that moves soil from
one place and deposits it in another.
(e) Spores:
Spores are the single-celled reproductive unit of nonflowering plants, bacteria, fungi, and algae.
Basically, spores are the babies, except they didn't need a mom and a dad. Not all life forms reproduce
sexually. Many, such as fungi and bacteria, reproduce without mating at all.
(f) Bacteria and Other Micro-organisms:
Microorganisms differ from each other not only in size, but also in structure, habitat,
metabolism, and many other characteristics. ... Microbes within the domains Bacteria and Archaea
are all prokaryotes (their cells lack a nucleus), whereas microbes in the domain Eukarya are
eukaryotes (their cells have a nucleus).
2. Man Made Or Anthropogenic:
a. Industrial units
b. Thermal power plants
c. Automobile exhausts
d. Fossil fuel burning
e. Mining
f. Nuclear explosions
(a) Industrial Units:
Air pollution is the permeation of particulates, biological molecules, or other harmful gases into
Earth's atmosphere, causing disease, damage to other living organisms. Air pollution may come from
reliable industries or natural sources. The atmosphere is a complex natural gaseous system that is
essential to support life on planet Earth. Stratospheric ozone depletion due to air pollution has been
recognized as a threat to human health as well as to the earth’s ecosystems.

4. (b) Thermal Powerplant:
A thermal power plant is a power station that converts heat energy into electric power. These power
plants do this by primarily heating fossil fuels, which heats up water into steam. The steam moves
through a turbine, which generates the electricity, and then it is condensed and recycled back to its
pre-heated starting point. Whilst thermal power plants give out a lot of gases that are harmful to the
environment, they also give out what is known as thermal pollution. Thermal pollution is the
degradation of the local environment, in particular the localized waterways, that are changed by the
discharge of waste water from the power plant.
(c) Automobiles Exhausts:
After the fuel is burned in the pistons, the gases and heat created must be discharged from the cylinder
to make room for the next infusion of fuel. The exhaust system is also responsible for reducing the
noise caused by the explosion of the fuel.
Exhaust gases are discharged from the cylinder through an exhaust valve. The exhaust gathers in an
exhaust manifold before eventually being channeled through the exhaust pipe and muffler and finally
out the tailpipe and away from the car. The muffler is constructed with a maze of what are called
baffles, specially developed walls that absorb energy, in the form of heat, force, and sound, as the
exhaust passes through the muffler.
The burning of fuel creates additional byproducts of hazardous gases— hydrocarbons, carbon
monoxide, and nitrogen oxide—which are harmful both to the engine's components and to the
environment. The emission control system of a car is linked to the exhaust system, and functions in
two primary ways. The first is to reduce the levels of unburned fuel. This is achieved by returning the
exhaust to the fuel-air mixture injected into the cylinders to burn as much of the exhaust as possible.
The second method is through a catalytic converter. Fitted before the muffler, the catalytic converter
contains precious metals that act as catalysts. That is, they increase the rate of conversion of the
harmful gases to less harmful forms.
(d) Fossil fuel burning:
A fossil fuel is a fuel formed by natural processes, such as anaerobic decomposition of
buried dead organisms, containing organic molecules originating in ancient photosynthesis that
release energy in combustion.[2]
Such organisms and their resulting fossil fuels typically have an age
of millions of years, and sometimes more than
650 million years.[3]
Fossil fuels contain high percentages of carbon and include petroleum, coal,
and natural gas. [4]
Peat is also sometimes considered a fossil fuel. [5]
Commonly used derivatives of
fossil fuels include kerosene and propane. Fossil fuels range from volatile materials with low carbon-
to-hydrogen ratios (like methane), to liquids (like petroleum), to nonvolatile materials composed of
almost pure carbon, like anthracite coal. Methane can be found in hydrocarbon fields alone, associated
with oil, or in the form of methane clathrates.
(e) Mining:
Mining is the extraction of valuable minerals or other geological materials from the earth, usually
from an orebody, lode, vein, seam, reef or placer deposit. These deposits form a mineralized package
that is of economic interest to the miner.
Ores recovered by mining include metals, coal, oil shale, gemstones, limestone, chalk, dimension
stone, rock salt, potash, gravel, and clay. Mining is required to obtain any material that cannot be
grown through agricultural processes, or created artificially in a laboratory or factory. Mining in a
wider sense includes extraction of any non-renewable resource such as petroleum, natural gas, or
even water.
(f) Nuclear explosions:
A nuclear explosion is an explosion that occurs as a result of the rapid release of energy from a high-
speed nuclear reaction. The driving reaction may be nuclear fission or nuclear fusion or a multi-stage
cascading combination of the two, though to date all fusion-based weapons have used a fission device

5. to initiate fusion, and a pure fusion weapon remains a hypothetical device.
Atmospheric nuclear explosions are associated with mushroom clouds, although mushroom clouds
can occur with large chemical explosions. It is possible to have an air-
burst nuclear explosion without those clouds. Nuclear explosions produce radiation and radioactive
debris.
Air Pollutants:
1. Substance dwelling temporarily or permanently in the air.
2. Alters the environment by interfering with the health, the comfort, or the food chain, or by
interfering with the property values of people
3. A pollutant can be solid (large or sub-molecular), liquid or gas.
4. It may originate from a natural or anthropogenic source (or both).
Classification Of Pollutants:
Pollutants can be grouped in two categories:
1. Primary pollutants
2. Secondary pollutants
Primary Pollutants:
Which are emitted directly from identifiable sources. Primary pollutants are any type of pollutant
directly into the environment. They differ from secondary pollutants because secondary pollutants
must form in the atmosphere, whereas primary pollutants do not. Primary pollutants can be emitted
from many sources including cars, coal-fired power plants, natural gas power plants, biomass burning,
natural forest fires, volcanoes, and many more.
The effects of primary pollutants are of concern as they can be harmful to humans, animals and plants.
Their contribution to the formation of secondary pollutants is also concerning, as this is what causes
harmful ground level ozone to form, along with different smogs, especially in densely populated cities
such as Los Angeles.
The emission of primary pollutants has decreased considerably in the past years, due to improved
regulations, technology and economic changes.[3]
Click here to see some cool images from NASA on
how air pollution has decreased in the past years.
Some Major Primary Pollutants:
1. Nitrogen oxides (NOx)
2. Carbon monoxide (CO)
3. Volatile organic compounds (VOCs)
4. Sulfur oxides (SOx)
5. Particulate matter (PM)
6. Mercury and more…
Secondary Pollutants:
Which are produced in the atmosphere when certain chemical reactions take place among primary
pollutants. Secondary pollutants are pollutants which form in the atmosphere. These pollutants are
not emitted directly from a source (like vehicles
or power plants). Instead, they form as a result of the pollutants emitted from these sources reacting
with molecules in the atmosphere. Pollutants that are emitted into the environment from a source
are called primary pollutants.
Secondary pollutants are concerning as they can be formed from many different compounds. The
phenomena of photochemical smog (seen in high density cities, see Figure 1) is a result of the
interactions of primary pollutants with other molecules in the air such as molecular oxygen, water
and hydrocarbons.

6. Some Major Secondary Pollutants:
1. Ozone (O3)
2. Sulfuric acid and nitric acid (component of acid
rain)
3. Particulate matter
4. Nitrogen dioxide (NO2)
5. Peroxyacyl nitrates (PANs) and more…
Effects Of Air Pollution:
It is impossible to describe the whole extent of potential and actual damage caused by all forms of air
pollution. But here are the main consequences:
Effect on Environment:
Air pollution has a major impact on the process of plant evolution by preventing photosynthesis in
many cases, with serious consequences for the purification of the air we breathe. It also contributes
to the formation of acid rain, atmospheric precipitations in the form of rain, frost, snow or fog, which
are released during the combustion of fossil fuels and transformed by contact with water steam in the
atmosphere.
Effect on Global Warming:
On top of that, air pollution is a major contributor to global warming and climate change. In fact, the
abundance of carbon dioxide in the air is one of the causes of the greenhouse effect.
Normally, the presence of greenhouse gases should be beneficial for the planet because they absorb
the infra-red radiation produced by the surface of the earth. But the excessive concentration of these
gases in the atmosphere is the cause of the recent climate change.
Effect on Human:
Our continual exposure to air pollutants is responsible for the deterioration of human health. Air
pollution is indeed a significant risk factor for human health conditions, causing allergies,
respiratory and cardiovascular diseases as well as lung damage.
High levels of air pollution can cause an increased risk of heart attack, wheezing, coughing, and
breathing problems, and irritation of the eyes, nose, and throat.
Air pollution can also cause worsening of existing heart problems, asthma, and other lung
complications.
Effect of Air Pollution on Health:
1. An increase in lung cancer cases
2. An increase in the frequency of chronic asthma crisis
3. An increase in the frequency of asthma cases
4. An increase in the frequency of coughing/phlegm
5. An increase in the acute disorders of upper repiratory system
6. An increase in eye, nose and throat irritation cases
7. Reduction in respiratory capacity
8. An increase in mortality

7. 9. A reduction in productivity and production An increase in
medical treatment expenses
Here are some other effects on human:
1. Irritates respiratory system and causes bronchitis
2. Irritates all parts of respiratory system
3. Causes lung irritation and also irritation in eyes
4. Deprives body cells of oxygen and cause unconsciousness by CO
combining with hemoglobin.
How to Control Air Pollution?
Action that we can take to reduce Air Pollution:
a. Conserve energy - at home, at work, everywhere.
b. Look for the ENERGY STAR label when buying home or office
equipment.
c. Carpool, use public transportation, bike, or walk whenever possible
d. Follow gasoline refueling instructions for efficient vapor recovery, being
careful not to spill fuel and always tightening your gas cap securely.
e. Consider purchasing portable gasoline containers labeled “spill-proof,” where
available.
f. Keep car, boat, and other engines properly tuned.
g. Be sure your tires are properly inflated.
h. Use environmentally safe paints and cleaning products whenever
possible.
i. Mulch or compost leaves and yard waste.
j. Consider using gas logs instead of wood.
On Days when High Ozone Levels are Expected, Take these Extra Steps to Reduce Air
Pollution:
a. Choose a cleaner commute - share a ride to work or use public
transportation.
b. Combine errands and reduce trips. Walk to errands when possible.
c. Avoid excessive idling of your automobile.
d. Refuel your car in the evening when its cooler.
e. Conserve electricity and set air conditioners no lower than 78 degrees.
f. Defer lawn and gardening chores that use gasoline-powered equipment, or wait
until evening.
On Days when High Particle Levels are Expected, Take these Extra Steps to Reduce Air
Pollution:
a. Reduce the number of trips you take in your car.
b. Reduce or eliminate fireplace and wood stove use.
c. Avoid burning leaves, trash, and other materials.
d. Avoid using gas-powered lawn and garden equipment.
You can also take steps to minimize your exposure to Air Pollution and protection your health:
a. Information on the health effect of ozone
b. Information on the health effect of particles.

8. Air Pollution Control In Textile:
Pollution control Spinning mill:
1. Maintaining m/c parts.
2. Maintaining hardness of rubber cots.
3. Maintaining RH%.
4. Using overhead pneumatic cleaners.
5. Cyclone filters, cloth filters.
Pollution Control Wet processing unit:
1. Electrostatic precipitator.
2. Scrubber.
3. Oxidize
Air Pollution Controlling Equipments:
Gravitational settling chamber:
a. Used to remove particles with size greater than 50μm.
b. Velocity of flue gas reduced in large chamber.
c. Particles settle under gravitational force.
Advantages:
a. Low initial cost.
b. Easy to design.
Disadvantages:
a. Require large space.
b. Less collection efficiency.
Cyclone Separator:
a. Centrifugal force is utilized to separate the particulate matter
b. It can remove 10 to 50 μm particle size
c. Used mostly in industries
Advantages:
a. Low initial cost.
b. Require less floor area.
c. Simple construction and maintenance.
d. Can handle large volume of gas at high temperature.
Disadvantages:
a. Requires large head room.
b. Less efficiency for smaller particles (<10μm).
c. Sensitive to variable dust load and flow

9. Conclusion:
Air pollution is a major problem in our country. Many peoples are getting sick because of Air
Pollution. Air pollution creates so many problem in our society. It effects on global warming. To
protect our earth we must have control air pollution. We need to be very careful about air pollution.
If we can control air pollution one day our earth will be a paradise. A proverb goes that “Safe Air
Safe Life”.
---The End---
Submitted By:
Md Rakibul Hassan
Id : 183014057
Article collected from:
https://en.wikipedia.org/wiki/Air_pollution
https://www.health.nsw.gov.au/environme
nt/air/Pages/common-air-pollutants.aspx
https://scholar.google.com/