Prof. Rajesh BhagatAsst. Professor

Civil Engg. Department

Y. C. C. E., Nagpur

Mobile No.:- 8483003474 / 8483002277

Email ID:- rajeysh7bhagat@gmail.com

Website:- www.rajeysh7bhagat.wordpress.com

B. E. (Civil Engg.) M. Tech. (Environmental Engg.)

GCOE, Amravati VNIT, Nagpur

1) GATE Exam Qualified Two Times.

2) Junior Engineer, Z. P. Washim.

3) Lecturer , K.D.K. College of Engineering, Nagpur

4) Lecturer, P. R. Pote (Patil) College of Engg., Amravati.

5) Assistant Professor, P.C.E., Nagpur.

6) Assistant Professor, Cummins College of Engg. For Women, Nagpur.

7) Scientist, Council of Scientific & Industrial Research, India.

References:

1) M.N. Rao & H.V.N.Rao, “Air Pollution”, Tata McGraw Hill Publishing Co. Ltd.

2) C.S. RAO,”Environmental Pollution Control Engineering, Wiley Estern Ltd. New

Delhi.

3) Stern A. C. , “Air pollution” Vol I to X

4) K. V. S. G. Murlikrishna “Air Pollution” JTNU, Kakinada.

5) Bhide & Sunderesan “Solid Waste Management in Developing countries,

INSDOC, Delhi.

6) Tohobanoglous, “Intgrated Solid Waste Management Engineering Principle and

Management Issues.

http://www.unep.or.jp/Ietc/Publications.

http://www.google.co.in/imgres

http://nptel.ac.in/courses

UNIT-I1. Introduction to Air Pollution.

2. Classification and Sources of Air Pollutants.

3. Effects of Air Pollutants on Man, Plants, Animal & Materials .

4. Atmosphere and Its Zones.

5. Air Pollution Episodes.

3DTEL

UNIT-II1. Meteorological parameters: Primary & secondary.

2. Atmospheric stability & plume behavior.

3. Air sampling and measurement.

4DTEL

UNIT-III1. Air Pollution Control: Industrial Air Pollution Controlling Devices,

Gravity Settling Chamber, Cyclone & Fabric Filter, Wet Scrubber &

Electrostatic Precipitator.

2. Gaseous Air Pollution Controlling Devices: Absorption, Adsorption &

Oxidation.

3. Automobile Exhaust.

4. Noise Pollution, Its Effects & Control.

5DTEL

What is Environment ?

• Natural world

• Surrounding in which we live

• Life sustaining system in which various living and non-living things are inter-related

• Collection of all the external factors or conditions influencing the life of the organisms

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Pollution is defined as the excessive discharge of undesirable substances into the

environment, adversely altering the natural quality of the environment and causing damage

to humans, plants and animals.

1) Water Pollution

2) Soil Pollution

3) Air Pollution

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What is Air Pollution ?

•Perception (When did you last say – Hey, that is air pollution ?)

–Visible (smoke, dust, chimney smoke) (Grey Scale)

–Odour (petrol, diesel, H2S, bleaching powder)

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How will you define Air Pollution?

Air pollution is the presence of one or more contaminants in the ambient atmosphere which is

injurious to living and non-living things or which unreasonably interfere with the comfortable

enjoyment of life and property.

Air pollution is the presence of foreign matter in the air either gaseous or particulate or combination

of both which is dangerous to the health and welfare of human beings.

Air pollution is the excessive concentration of foreign matter in the air which adversely affects the

human-being or living things or causes damages to property.

Air pollution is the presence of substances in air in sufficient concentration and for sufficient time, so

as to be, or threaten to be injurious to human, plant or animal life, or to property, or which

unreasonably interferes with the comfortable enjoyment of life and property. Air pollutants arise from

both manmade and natural processes.

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What is clean air ?

:- 78.1% Nitrogen + 20.9% Oxygen + 1% Trace

12

Composition of Dry Atmospheric Air

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Why it is important to study air pollution:-

Man can Survive

for 5 weeks without food,

For 5 days without water,

But cant survive 5 minutes without air

Man consumes 2 liters water per day

Man breaths on an avg. 25000 times a day at a rate of 1-2 liters per breath

It means requires enormous quantity of air for his survival and it goes into direct contact with the

most sensitive organs of the human body.

In water Conc. Of lead More than 300000ug/m3 is harmful.

In air conc. Of lead more than 1.5ug/m3 is harmful.

Once it is discharged in the atmosphere then it is impossible to control.

Air pollutants can transfer from one point to other and can give adverse effect …..

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16Natural and Artificial Sources of Air Pollution

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Air pollutant:- A substance in the air that can cause harm to humans and the environment is

known as an air pollutant.

The ambient air quality may be defined by the concentration of a set of pollutants which may

be present in the ambient air we breath in. These pollutants may be called criteria pollutants.

Ambient air quality refers to the quality of air in our surrounding environment. It is typically

measured near ground level, away from direct sources of pollution.

Emission standards express the allowable concentrations of a contaminant at the point of

discharge before any mixing with the surrounding air.

Emission standards are legal requirements governing air pollutants released into the

atmosphere. Emission standards set quantitative limits on the permissible amount of specific air

pollutants that may be released from specific sources over specific timeframes.

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Types of Air Pollutants:

Primary Air Pollutant: Harmful substance that is emitted directly into the atmosphere.

Ex. Natural Contaminants, Particulate Matter (PM), Sulfur dioxide, Oxides of Nitrogen, Carbon

Monoxide, Carbon Dioxide, Hydrogen Sulfide, Hydrogen Fluoride, Hydrocarbons, Volatile

Organic Compounds (VOC), Toxic Metals, such as lead, cadmium and copper,

Chlorofluorocarbons (CFCs), Ammonia (NH3), Odors, Noise, etc.

Secondary Air Pollutant: These are not emitted directly but formed in the atmosphere when a

primary air pollutant reacts with substances normally found in the atmosphere or with other air

pollutants.

Examples are ground level Ozone, Smog (Photochemical Smog), Peroxy-Acytyl Nitrate (PAN),

Formaldehyde, Acid Mist, etc.

Some pollutants may be both primary and secondary: that is, they are both emitted directly and

formed from other primary pollutants.

DTEL 21

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23Table 6.1 Air Pollutants (16)

Major Classes of Air Pollutants:

1) Particulate Matter (Dust, Fog, Mist, Fumes)

2) Oxides of Nitrogen( NO, NO2, NO3)

3) Oxides of Sulphur ( SO2, SO3, etc)

4) Oxygen compound (CO, CO2, O3)

5) Hydrocarbons (VOC, CH4, Non CH4)

Air Pollutants:-

1) Natural Contaminants:-

Ex. Natural Fog, Pollen grains, bacteria, and product of volcanic eruption.

Pollen is important because of its peculiar properties irritating to some individuals.

It discharged into atmosphere from plant, vegetation, weeds, trees grass, etc.

Many people suffers from asthama or hey fever & bronchitis (respiratory disease).

2) Aerosols (Particulate Matter):- (200 ug/m3)

Ex. Dust, Smoke, Mist, Fog, & Fumes.

Solid or liquid particle of microscopic size suspended and dispersed in a gas or

atmosphere.

They range from 0.01 to 500 u.

Aerosol also defined as a colloidal system in which the dispersion medium is a gas

and the dispersed phase is a solid or liquid.

They differs widely in terms of particle size, particle density and their importance as

pollutants.

PM10 & PM2.5

Dust:-

Small solid particle generated by crushing, grinding, blasting of material.

range from 1u to 200u.

Can settle under gravity.

Ex. Fly Ash, Cement, Foundry dust, etc

Smoke:-

Aerosol particle resulting from incomplete combustion.

size less than 1u.

Fog:-

Liquid particle formed by condensation of vapour.

Visible aerosol

Dispersed phase is liquid

Reduces visibility less than 0.5 km

Size range from 1u to 40u.

Mist:-

Liquid particle formed by condensation of vapour.

Water droplet in air of size 40u to 500u

Visibility upto 1km or more

Low concentration of dispersion of liquid particle of large size.

Fumes:-

Very fine solid particle.

Size 0.001 to 1u.

Unpleasant smelling airborne effluent.

Generated by condensation from the gaseous state and often accompanied by a

chemical reaction such as oxidation.

3) Gases:-

Sulphur Dioxide,

Oxide of Nitrogen,

Hydrogen sulphide,

Carbon Monoxide,

Carbon Dioxide,

Hydrogen Fluoride,

Hydrogen Chloride,

Hydrocarbons,

Aldehydes,

Radio active gases,

CFC, etc.

Sulphur Dioxide:- 80 ug/m3

Principal constituents of air pollutants.

Combustion of fuel specially coal.

Sulphur content of fuel.

Crude petroleum product contain1% to 5% of sulphur content.

Fuel gases contain sulphur but small quantity.

Another source is metallurgical operations.

Many ores like zinc, copper, lead are primarily sulphides.

Sulphuric acid plant.

Paper manufacturing plant.

Incinerator.

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Oxides of Nitrogen:- 80 ug/m3

2nd most abundant atmospheric contaminants.

Highest conc. Of NOx in effluent from industry where nitric acid is used.

Next highest conc. is in automobile exhaust.

Large power plant, low heat burners, furnace etc. also contribute.

High temp. processes.

DTEL 36

Carbon Monoxides:- 2000 ug/m3 (0.03%)

Odourless & colourless gas.

Dangerous gaseous pollutant.

Produced from incomplete combustion of carbonaceous matter.

Chief source is automobile exhaust.

Loss of consciousness, concentration, headache, retardation of mental activity,

weakness, etc.

Reacts with haemoglobin of blood to give carboxy haemoglobin.

Hydrogen Sulphide:- 2 ug/m3 (Rotten egg emits.)

highly toxic, flammable & Foul smelling gas.

Anaerobic biological decay processes.

Volcanoes & water springs.

Kraft pulp industry, petroleum refineries, coke-oven plants & chemical processes.

Carbon Dioxide:- CO2

Occurs naturally in the atmosphere.

Essential ingredient in photosynthesis, the process by which plants make food and

energy.

Released due to respiration by animal & plant.

Deforestation and the burning of fossil fuels such as coal

Eruption of volcanoes, forest fires, biological decay, etc.

Green house gas increase mean ambient temp & mean sea level.

Hydrogen Fluoride:- HF

Major- Manufacturer of phosphate fertilizer, aluminum industry, brick plants, etc.

Minor - Other metallurgical operations & burning of coal.

More important in terms of injury to vegetation & animal than human.

Hydrogen Chloride:- HCl

Industrial Chemical processes.

Effects on respiratory irritation from chlorine.

Damage to vegetation.

Corrosion.

Chloro Fluro Carbon:- CFC

Non-toxic, non-flammable & non-carcinogenic.

But harmful or damages to ozone layer allows UV rays to reach the earth surface.

A.C., Refrigerator, Sprays, etc.

Aldehydes:-

Combustion of gasoline, diesel, oil, fuel, & natural gas.

Incomplete oxidation of motor fuel & lubricating oils.

Irritates to eyes.

Radioactive Gases:-

Nuclear power reactor & related fuel handling facilities.

Experimental accelerator, testing of nuclear bombs, agricultural, industrial ,

medical use of radioactive isotopes.

DTEL 41

Ozone:-O3

In the earth’s upper atmosphere ozone plays imp. role by providing a shield from UV rays

but Ozone at GL is harmful air pollutant.

Not emitted directly in the air but it is created by chemical reaction between NOx & VOC

in presence of sunlight. 3O2 ( + NO2 catalyst & Sunlight) ==> 2O3

Breathing Ozone trigger health problems like asthama, chest pain, coughing, throat

irritation & congestion.

Reduces lung function & inflame the lining of lungs.

Smog:-

Combination of smoke & fog.

Photochemical & Coal Induced smog.

Restricted & highly motorized area in metro cities.

Occurs under adverse meteorological condition when air movement is restricted.

Reduces visibility, causes eye irritation, damages to vegetation & cracking of rubber.

Prolonged exposure may result high mortality rate.

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Photochemical Smog

46Fig. 6.2 Air Pollutant Sources (16)

Acid Mist / Acid Rain:-

Acid mist or acid rain is any other form of precipitation that is unusually acidic,

meaning that it possesses elevated levels of hydrogen ions (low pH). It can have harmful

effects on plants, aquatic animals and infrastructure.

PAN ( Peroxy Acytyl Nitrate):-

Produced from the combination of hydrocarbons, and nitrogen dioxide in the presence of

sunlight and heat.

Hydrocarbons + O2 + NO2 + light → CH3COOONO2 (PAN)

The general equation is CxHyO3 + NO2 → CxHyO3NO2

Cause eye irritation, damages to plant, skin cancer, etc.

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Formaldehyde:-

It is organic chemical prevalent in environment.

Colourless gas with pungent odour from family of gases aldehyde.

It is formed by numerous natural sources & anthropogenic activities.

Released from through biomass combustion / forest fires, decomposition & through

volcanoes.

Power plant, incineration, automobile exhaust, etc.

Cause cancer.

Irritation to respiratory tract.

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Effects of Air Pollution on Human Health:-

Man easily affected by air pollution. Inhalation of air pollutants through respiratory system

gives direct impact on human health.

Factors affecting impact of air pollutants on man are :-

Type of air pollutant.

Concentration of air Pollutant.

Duration of exposure of air pollutant.

Health condition of the receptor.

Age group of the receptor.

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Effects of Air Pollution on Human Health:-

Cause irritation to the eye.

Cause nose & throat irritation.

SO2 & PM: Irritate respiratory tract and causes damages to lungs.

NO2: Causes airway restriction

CO: reduces carbon carrying capacity of blood, Causes headache, fatigue, drowsiness,

death.

CO increase stress on those suffering from cardio-vascullar & pulmonary disease.

Ozone: Causes burning eyes, coughing, and chest discomfort

Gases like H2S, amonia, etc. cause odour nuisance.

Increases mortality rate & morbidity rate.

Pollen initiate asthamatic attack.

Chronic pulmonary disease like bronchitis & asthama are aggravated by SO2, NO2, PM,

Smog, etc.

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Effects of Air Pollution on Human Health:-

HF cause diseases of the bone (fluorosis) & molting of teeth.

Carcinogenic agents causes cancer.

PM (Dust) cause respiratory disease like silicosis, asbestosis, etc.

Heavy metals like lead cause poisoning.

Retardation of mental activity.

Loss of concentration, weakness, etc.

Cause skin cancer.

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Effects of Air Pollution

Table 6.2 Air Pollutant Effects (16)

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Effects of Air Pollution on Animal:-

Two step process:-

I. Accumulation of the air borne contaminant in the vegetation & forage.

II. Subsequent poisoning to the animals when they eat it.

3 Pollutants responsible for damage are Fluorine, Dust & Lead.

Fluorine can cause rapid loss in weight, decline in health, poisoning, etc.

It may increase bone failure.

Arsenic in dust or spray on plants lead to poisoning of animal

Air pollutants can causes salivation, thirst, vomiting, uneasiness, irregular pulse &

respiration.

Depressing effect on central nervous system.

Animal becomes dull & losses weight.

Can result in paralysis and death.

Acid rain falling in rivers, killing fish that are sensitive to pH fluctuations.

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Effects of Air Pollution on Plant :-

Interfere with plant growth.

weakens plants and makes them more susceptible to insect infestation.

Reduces the amount of light reaching the leaf by clogging the stomata & reduces CO2

intake & thus interfere with photosynthesis.

Damages to leaves ( bleaching of leaves, collapse of leaf, necrosis of leaves, etc.)

Retard the yield.

Acute & chronic injury to plant.

Spoil the appearance of plant.

Air Pollutants affecting Plant:- SO2, PM, HF, O3, NOx, HCl, etc.

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Effects of Air Pollution on Material :-

Damages the material or metals by corrosion. SO2---SO3----H2SO4

CO2 in presence of moisture produces Carbonic acid, which is then leached out as water

soluble bicarbonate.

PM adhere to building surfaces to produce unsightly coating.

Paint is also affected & requires frequent painting.

H2S is common cause of darkening of surfaces covered with paint.

SO2 cause deterioration of natural & some synthetic textile fibers.

O3 cause pronounced fading of certain dyes on cotton & rayon fabrics.

Rubber can be damaged by cracking.

Sox causes lather to lose its strength & ultimately disintegrate.

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Air Pollutants cause damage to material by 5 mechanism :-

1) Abrasion:-

Solid particle of sufficient size & travelling at high velocities can cause abrasion action &

accelerate wear.

2) Deposition & Removal:-

Particle deposited on a surface may spoil appearance & also may cause some deterioration.

3) Direct Chemical Attack:-

React directly & irreversibly with material to cause deterioration. Ex. Bleaching of marble by

SO2 & etching of a metallic surface by acid mist.

4) Indirect Chemical Attack:-

Certain material absorbs some pollutants & get damaged when the pollutants undergo

chemical changes. Ex. SO2 absorbed by leather is converted to H2SO4, which deteriorates the

leather.

5) Corrosion:-

Atmospheric deterioration of ferrous metal is by an electro-chemical process ie corrosion.

Table 6.3 Air Pollutant effects (16)

Table 6.4 Air Pollutant Effects (16)

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Effects of Air Pollution on Atmosphere:

1) Inversion.

2) Acid Rains.

3) Global warming / Climate Change / Green house effects.

4) Heat Islands.

5) Ozone Depletion.

6) Photochemical Smog.

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Effects of Air Pollution on Atmosphere:

1) Can cause visibility reduction.

2) Change in precipitation.

3) Fog formation.

4) Solar radiation can be reduced.

5) Can cause alternation in temp. and wind distribution.

6) Global warming.

7) Humid condition.

8) Depletion of ozone layer.

9) Life of mosquitoes can be increased.

10) Can cause Heat Islands.

11) Acid Rains.

12) Water Logging.

13) Change in mean sea level, energy supply & demand, water sources availability, and its

consequences etc.

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Heat Islands :-

1) Cities are warmer than their rural surroundings.

2) In highly urbanized & industrialized area a difference in temp of 6 to 100C.

3) Cities are warmer, rainier and foggier.

4) Heat energy release causes a significant climate change.

5) Thermal capacitance of street, buildings & Industries for solar input & Energy dissipation.

6) Artificial production of energy approaches nearly 1000 watts/m2 while the solar absorption

by the atmosphere averages out to be only 25 watts/m2.

7) Energy release may occur through evaporation of water and direct heat of air.

8) Further cone. Of GHGs may increase the heat content of urban area.

9) Inevitably disrupt the climatological & ecological balance.

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Air Pollution Episodes:-

1) 1930 -3 Day Fog in Meuse Valley, Belgium

2) 1931 -9 Day Fog in Manchester, England

3) 1948 -Plant Emissions in Donora, Penn, US

4) 1952 -5 Day Smog in London, England

5) 1970 –Radionuclide Emissions, Three Mile Island, US

6) 1984 -Release of Methyl Iso-Cynate (MIC) in Bhopal, India

7) 1986 -Radionuclide Releases, Chernobyl, Ukraine

8) 1997 – Haze Disaster in Indonesia

9) 2001 – Wildfires in Sierra Nevada, US

10) 2001 – Enormous Clouds of Dust in New York during Collapse of World Trade Center, US

11) 2002 – Violent Dust Storm in Queensland, Australia

12) 2005 - Jilin Chemical Plant Explosions, Jilin city, China

13) 2007 – Wildfires in TALLAHASSEE Florida, US

14) 2008 - Kingston Fossil Plant Coal Fly Ash Slurry Spill, Kingston, US

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Bhopal Gas Tragedy:

1) On the night of December 2, 1984, the Union Carbide Pesticide Plant in Bhopal, India

began to leak methyl Iso-Cyanate gas and other poisonous toxins into the atmosphere.

2) About 40 tons of toxic gases had leaked and spread throughout the city.

3) The Bhopal Disaster was the worst episode in the history of industrial air pollution.

4) Over 5,00,000 were exposed and there were up to 15,000 deaths at that time.

5) In addition, more than 20,000 people have died since the accident from gas-related

diseases.

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Bhopal Gas Tragedy:

1) The cause was the entry of water into Methyl Iso-Cyanate (MIC) storage tank.

2) Resulting exothermic reaction increase the temp. inside tank above 2000C and raised the

pressure. (BP of MIC is 390C)

3) Safety system failed.

4) Gases were blown by wind towards city Bhopal.

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The Great London Smog:- (The Killer Smog) 4th Dec. 1952

1) With the advent of industry, London’s population was accustomed to seeing foggy,

pollution laden air.

2) In 1952 however, this pollution took a tragic turn in winter.

3) Weather was cold & residents burned more coal in their fireplaces to reduce the chill.

4) High-pressure air mass created a subsidence & temperature inversion.

5) The smoke with sulfur dioxide & nitrogen oxides and left London cover in a black

cloud of near total darkness.

6) The old and respiratory affected died first, but younger people exposed to the outside

atmosphere were also affected.

7) The maximum daily SO2 concentration recorded at that time was 4000 µg/m3, smoke

levels were 4.46 mg/m3 & PM were 5 times higher than normal.

8) The Great London Smog lasted for five days and lifted on 9th Dec, resulting in about

12000 deaths & 100,000 illnesses.

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The Los Angeles Smog:-

1) July 1973.

2) Photochemical Smog episode.

Donora (Washington) Fog, 27th Oct. 1948:-

Horror visited the US Steel company town of Donora.

The fog started building up in Donora on October 27, 1948, on the night when a temp.

inversion started and made sudden attack on the town.

Fluoride emissions from the Donora Zinc Works smelting operation and other sources

containing sulphur, carbon monoxide and heavy metal dusts were trapped by weather

conditions.

Causing coughing and other signs of respiratory distress (pain) for many residents of

the community.

Illnesses, asthma and deaths had taken place.

The smog continued until it rained on October 31, by which time 20 residents of

Donora had died and approximately 2000 residents had been suffered.

Another 50 residents died of respiratory causes within a month after the incident.

Meuse Valley, Dec. 1930 (Inversion) :-

1) First week of December 1930, when a thick mist lay over large parts of Belgium

Country.

2) Several thousand cases of acute pulmonary attacks occurred in the densely populated

valley of the Meuse.

3) Resulting in 60 deaths.

4) The cause was poisonous products in the waste gas of the many factories in the valley,

in conjunction with unusual climatic conditions.

5) The disaster in all probability had been brought about by sulphur dioxide (SO2) or

oxidation products of that compound.

6) During that time, the day temperature was a little above freezing point while at night it

measured up to 10oC below, while the wind speed was only 1-3km/hr.

Meuse Valley, 1930

Kingston Fossil Plant coal fly ash slurry spill occurred just before 1 a.m. on Monday

December 22, 2008, when an ash dike (artificial wall or slope) ruptured at an 84-acre solid

waste containment area at the Kingston Fossil Plant in Roane County, Tennessee, USA.

1.1 billion US gallons (4,200,000 m3) of coal fly ash slurry was released.

The slurry (a mixture of fly ash and water) traveled across the Emory River on to the

opposite shore, covering up to 300 acres (1.2 km2) of the surrounding land,

damaging homes and flowing up and down stream in nearby waterways such as

the Emory River and Clinch River.

It was the largest fly ash release in United States history.

Kingston Fossil Plant coal fly ash slurry spill

The Jilin chemical plant explosions were a series of explosions which occurred on

November 13, 2005, in Petrochemical Plant in Jilin City, Jilin Province, China, over

the period of an hour.

The explosions killed six, injured dozens, and caused the evacuation of 10,000

residents.

The blasts created an 80 km long toxic slick (oily substance) in the Songhua River.

2002 – Violent dust storm

in Queensland, Australia

Enormous clouds of dust in New York during Collapse of World Trade Center, US

SUMMARY

We discussed here about air pollution, types of air pollutants,

sources of air pollution and effects of air pollution.

SUMMARY

1) Define air pollutants? What are the major air pollutants? Explain?

2) Define Air pollution? Give various sources of air pollutants with example?

3) Classify air pollutants on basis of primary and secondary air pollutants.

4) Explain the effects of air pollution on man, animal and plant?

5) Explain the effects of air pollution on material and atmosphere?

6) Explain various zones of atmosphere by giving the details of temperature variation & gases present

in each zone?

7) Explain with sketch the temperature variation with height in atmosphere and its impact on air

pollution?

8) What are the Global effects of air pollution? Explain anyone?

9) Give the list Episode of Air pollution? Explain any one with its causes?

10) What are the causes and effects of Ozone depletion?

11) What is Green House Effect? Explain its causes & effects?

12) Write a short note on:

a)Air Pollution Standard in India b)Aerosol c)Heat Islands d) Acid rains

TYPICAL QUESTIONS

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Assignment-IWrite a report on following topics: (300 words for each)

1) Green House Effect

2) Global Warming

3) Climate Change

4) Heat Island

5) Acid Rain

6) Depletion of Ozone layer

7) Inversion

8) Eutrophication