Introduction to Air Pollution

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Chapter1Air Quality DefinitionsCharact
eristicsPerspectives
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What is Atmosphere?
An atmosphere is a layer of gas or layers of
gases that envelope a planet, and is held in
place by the gravity of the planetary body.
The atmosphere of Earth is composed of nitrogen
(78), oxygen (21), argon (0.9), carbon dioxide
(0.04) and trace gases.
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Biosphere is the zone of life on Earth
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Classification of atmosphere in layers
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Pressure variance
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Temperature variation

• When the altitude increases, the temperature
  decreases
• Jabal Aktar is cooler than Birkat almouz
• Himalayas 8824 m is much cooler than any other
  place in the world temperature is
  -60 degree Celsius

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COMPOSITION OF CLEAN AIR
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DEFINITION OF AIR POLLUTION
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REASONS FOR AIR POLLUTION
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IDENTIFYING AIR POLLUTION
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Natural Fog
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Pollen Grains
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Examples
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• An Illinois coal is burned at a rate of 1.00 kg
  per second. If the analysis of the coal reveals a
  sulfur content of 3.00 , what is the annual rate
  of emission of SO2?

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• MASS BALANCE
• Sin Sash SSO2
• Sin 1 kg/s x 0.030 0.030 kg/s
• Sin 9.46 x 105 kg/yr
• Sash (0.05)(9.46 x 105 kg/yr) 4.73 x 104
  kg/yr
• SSO2 Sin Sash 9.46 x 105 4.73 x 104
• SSO2 8.99 x 105 kg/yr
• SSO2 8.99 x 105 kg/yr (64 SO2/32 S)
• SSO2 1.80 x 106 kg/yr

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• Determine whether or not a pulverized coal, dry
  bottom, wall-fired boiler using bituminous coal
  at power plant rate at 61 MW meets the NSPS for
  SO2.The power plant burns bituminous coal with a
  sulfur content of 1.8 and ash content of 6.2 .
  The coal has a heating value of 14,000 Btu/lb.
  the boiler efficiency is 35. Use the emission
  factors to estimate the emissions. Assume the
  efficiency of SO2 control is 85 .

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• Coal firing rate 61 MW / 0.35 174.3 x 106 W
• Mass of coal burned
• 174.3 x 106 J/s (3600 s) (1 Btu/1054.4 J)
• 5.95 x 108 Btu/hr
• Using the EPA emission factor of 38S for
  bituminous coal
• Uncontrolled SO2 emission rate 38 (1.8)
• 68.4 lbm
• ton coal

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• Check emission rate
• Estimated SO2 emission rate
• 68.4 lb/ton coal(5.95 x 108 Btu)(1
  ton/2000lb)(0.15)
• 14,000 Btu/lb
• 218.05 lbm
• SO2 emission rate (per million Btu)
• 218.05 lb/(5.95 x 108 Btu)(106)
• 0.37 lb/million Btu
• Comment
• meets the standard 1.2 lb/million Btu but not the
  90 reduction requirement

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AIR POLLUTION EPISODES
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EPISODES

• EPISODE used as a refined form of the word
  disaster/ incident.
• Indeed it was the shock of these disasters that
  stimulated the first modern legislative action to
  control of air pollutants.
• Careful study of different known episodes reveal
  that all of the incidents had something in common.

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AIR POLLUTION EPISODES

• CRUCIAL INGREDIENTS FOR AN EPISODE TO HAPPEN
• Large number of population sources
• A restricted air volume
• Failure of officials to recognize that anything
  is wrong
• The presence of water droplets of the right size
• Source Goldsmith 1968

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AIR POLLUTION EPISODES
Major air pollution episodes(WHO, 1961) Major air pollution episodes(WHO, 1961) Major air pollution episodes(WHO, 1961)
Donora, 1948 London, 1952
Population 12,300 8,000,000
Weather Anticyclone inversion and fog Anticyclone inversion and fog
Topography River valley River plain
Most probable source of pollutants Industry steel and zinc plants Household and coal burning
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Major air pollution episodes (WHO, 1961) Major air pollution episodes (WHO, 1961) Major air pollution episodes (WHO, 1961)
Donora, 1948 London, 1952
Nature of illnesses Chemical irritation of exposed membranous surfaces Chemical irritation of exposed membranous surfaces
of deaths 17 4000
Time of death Began after second day of episode Began after second day of episode
Suspected cause of irritation Sulfur oxides with particulates Sulfur oxides with particulates
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Locationof Bhopal in India
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BACKGROUND INFORMATION

• The Bhopal disaster, also referred to as the
  Bhopal gas tragedy, was a gas leak incident in
  India, considered to be the world's worst
  industrial disaster.
• Monday, December 3rd, 1984. (28 years ago)

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BACKGROUND INFORMATION

• One of Union Carbides Pesticide factories was
• located in Bhopal, India.
• Union Carbide of India Limited (UCIL) was a
• subsidiary of The Union Carbide Corporation
  (UCC).
• The Factory produced carbanate pesticides. One
  Component was Methyl Isocyanate (MIC).
• A rapidly growing community of roughly 900,000
• people.

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The system that failed
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The Bhopal Disaster!

• 40 tons of deadly gases suddenly burst out into
  the atmosphere.
• Workers fled in panic.
• People woke up coughing violently and with eyes
  burning as if chilli powder had been flung into
  them.
• Neighbouring communities fled in panic
• The streets were foul with vomit. Those who fell
  were trampled by the crowd.
• The worst affected were the children unable to
  walk and breathe, they simply suffocated and died.

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The Bhopal Disaster!

• Local hospitals were soon overwhelmed with the
  injured
• Over 500,000 people were exposed to methyl
  isocyanate gas and other chemicals.

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Contributing Factors

• Factors leading to the magnitude of the gas
  leak mainly included problems such as
• storing MIC in large tanks and filling beyond
  recommended levels, poor maintenance after the
  plant ceased MIC production at the end of 1984,
• safety systems being switched off to save money
  including the MIC tank refrigeration system which
  could have mitigated the disaster severity.
• shortcomings in health care and socio-economic
  rehabilitation.

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Contributing Factors

• use of a more dangerous pesticide manufacturing
  method,
• plant location close to a densely populated area,
• undersized safety devices,
• Plant management deficiencies were also
  identified  lack of skilled operators, reduction
  of safety management, insufficient maintenance,
  and inadequate emergency action plans.

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AFTERMATH OF IT ALL

• The official immediate death toll was 2,259.
  The government of Madhya Pradesh confirmed a
  total of 3,787 deaths related to the gas
  release. Others estimate 8,000 died within two
  weeks and another 8,000 or more have since died
  from gas-related diseases. A government affidavit
  in 2006 stated the leak caused 558,125 injuries
  including 38,478 temporary partial injuries and
  approximately 3,900 severely and permanently
  disabling injuries.

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Victims Remain Victims

• gtResident Leela was one of those caught by Union
  Carbides cloud of poison gas.
• gtHer family of six survived, but ever since they
  have suffered from breathlessness and spells of
  vomiting. One of her sons has gone blind. All six
  family members suffer from breathlessness and
  spells of vomiting.
• gtBurdened by injury they cannot earn well. The
  familys joint income is 30 a month.
• For the gas victims of Bhopal every day of the
  past 28 years has been a struggle against
  breathlessness, nausea, brain damage, cancers,
  fevers, numbness, panic attacks, menstrual chaos,
  monstrous births.

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Economic Effects

• loss of jobs (650 permanent jobs were lost)
• loss of earning capacity of victims
• business disruptions
• cost of compensation
• rehabilitation, and legal costs.
• "Investment hasn't been coming to Bhopal because
  of the stigma."

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NOW

• Still in a state Recovering
• Almost 30 years later, one out of four babies
  born in Bhopal is born dead.
• Countless people suffer from breathing
  difficulties, cancer, nerve diseases and
  infertility.
• The ground water is still contaminated.

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NOW
Deteriorating portion of the MIC plant, decades
after the gas leak. Contributor to ongoing
contamination.
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NOW
Bhopal child born with birth defects
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GLOBAL EFFECTS OF AIR POLLUTION
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GLOBAL WARMING
What is global warming? Since the Industrial
Revolution, the global annual temperature has
increased in total by a little more than 1 degree
Celsius, or about 2 degrees Fahrenheit. Between
1880the year that accurate recordkeeping
beganand 1980, it rose on average by 0.07
degrees Celsius (0.13 degrees Fahrenheit) every
10 years. Since 1981, however, the rate of
increase has more than doubled For the last 40
years, weve seen the global annual temperature
rise by 0.18 degrees Celsius, or 0.32 degrees
Fahrenheit, per decade.
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What causes global warming? A Global warming
occurs when carbon dioxide (CO2) and other air
pollutants collect in the atmosphere and absorb
sunlight and solar radiation that have bounced
off the earths surface. Normally this radiation
would escape into space, but these pollutants,
which can last for years to centuries in the
atmosphere, trap the heat and cause the planet to
get hotter. These heat-trapping
pollutantsspecifically carbon dioxide, methane,
nitrous oxide, water vapor, and synthetic
fluorinated gasesare known as greenhouse gases,
and their impact is called the greenhouse effect.
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Earths Atmospheric Gases
Non-Greenhouse Gases 99
Greenhouse Gases1
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The image below describes the Greenhouse effect
and the role of greenhouse gases
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Greenhouse Effect
Sun
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The image shows the concentration of CO2 in the
atmosphere over a period of time if emissions
continue unaltered.
300
270
240
CO2 (ppmv)
210
180
Temp. Proxy
800
600
400
200
0
Thousands of Years Before Present
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Households are Big Contributors to Climate Change

• Of all U.S. greenhouse gas emissions come from
  households
• Vehicles
• Home Heating
• Electricity

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So how can each of us slow global warming now?
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Reduce our consumption of fossil fuels

• Because greenhouse gas emissions are tied very
  closely to our energy consumption, using less
  fossil fuel based energy puts fewer greenhouse
  gases into the atmosphere.
• This will help slow global warming.

Mountaintop removal for coal mining near Rawl,
West Virginia. 50 of electricity in the United
States is produced from coal.
(
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Average Electricity Emission Factors
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Kitchen Light Fixture
Three 60 Watt Bulbs
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197,100 1000 197.1 kWh/yr
54 x 10 540 Wh/day
18 x3 54 W
540x365 197,100 Wh/day
3 bulbs
18 W
10 hours a day
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197 kWh
35.46
115.34
228.52
743.3
514.8
79.88
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• We can make some simple substitutions

Replacing just 1 incandescent light bulb with 1
compact florescent bulb saves about 150 pounds of
carbon dioxide per year!
If every American household replaced just 5
high-use incandescent bulbs with compact
florescent lights we'd collectively save more
than 8 billion each year in energy costs and we
would prevent the greenhouse gases equivalent to
the emissions from nearly 10 million cars.
Source http//www.energystar.gov
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Be Bulb SmartUse CFLs
Whats the difference?
Compact Fluorescent
Incandescent

• 1,430 lbs. CO2 pollution avoided
• 30 saved

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Small changes really add up
Replace your old refrigerator with a new Energy
Star Annual savings 90 700 pounds
CO2
Set your thermostat down a few degrees in the
winter Annual savings 135 1400 pounds
CO2
Drive JUST 10 fewer miles per week Annual
savings 80 520 pounds CO2
Reduce your garbage by 10 through greater
recycling or reduced packaging Annual savings
1200 pounds CO2
Wash clothes in cold water only Annual savings
70 500 pounds CO2
Caulk and weather-strip around doors and
windows Annual savings 80 650 pounds
CO2
These are mid-range estimates from published
sources your savings may vary.
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How is global warming linked to extreme
weather? A Scientists agree that the earths
rising temperatures are fueling longer and hotter
heat waves, more frequent droughts, heavier
rainfall, and more powerful hurricanes.
What are the other effects of global warming?
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Major Effects Of Global Warming

• Melting Of Polar Ice Caps
• Rise in Sea Levels
• Throw global ecosystems out of balance
• Will endanger several species of animals

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• Other fallouts include
• Spread of disease
• Warmer waters and more hurricanes
• Increased probability and intensity of droughts
  and heat waves
• Economic consequences
• Loss of Biodiversity
• Destruction of Ecosystems

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Mitigation Of Global Warming

• Mitigation of global warming involves taking
  actions to reduce greenhouse gas emissions.

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Energy efficiency and conservation

• Urban Planning
• Building Design
• Use of passive solar building design, low-energy
  building, or zero-energy building techniques,
  using renewable heat sources
• Transport
• plug-in hybrid electric vehicles
• A shift from air transport and truck transport to
  electric rail transport
• Increased use of biofuels

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Carbon Capture And Storage(CCS)

• Carbon capture and storage (CCS) is a plan to
  mitigate climate change by capturing carbon
  dioxide (CO2) from large point sources such as
  power plants and subsequently storing it away
  safely instead of releasing it into the
  atmosphere.

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Carbon Sequestration

• Carbon sequestration is a term that describes
  processes that remove carbon from the atmosphere.
• Seeding oceans with iron
• Solar shades
• Geoengineering

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Seeding Oceans With Iron

• It is motivated by evidence that seeding the
  oceans with iron will increase phytoplankton
  populations, and thereby draw more carbon dioxide
  from the atmosphere.

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Solar Shades

• Some scientists have suggested using aerosols
  and/or sulfate dust to alter the Earth's
  reflectivity by burning sulfur in the
  stratosphere, as an emergency measure to increase
  global dimming and thus stave off the effects of
  global warming.
• It would, however, increase the environmental
  problem of acid rain and drought.

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Governmental And Intergovernmental Action

• Policies like
• Kyoto Protocol
• Carbon emissions trading
• Carbon tax

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Population Control

• The population explosion is a fundamental factor
  that has led to global warming
• Because of this, various organizations promote
  population control as a means for mitigating
  global warming. Proposed measures include
  improving access to family planning and
  reproductive health care and information, public
  education about the consequences of continued
  population growth.

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Ozone (O3) is a dangerous street level pollutant,
contributing to photochemical smog. It is also a
minor greenhouse gas, contributing to climate
change. The main reason people are aware of its
existence is through its beneficial effects in
the stratospheric ozone layer 5 to 30 miles up,
which provides an important protection for life
on Earth from the dangerous effects of the suns
radiation, by absorbing biologically damaging
ultraviolet sunlight (UV-B).
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The hole in the ozone layer was first noticed
over the British Antarctic Survey station Halley,
Antarctica10. Today, up to 60 of the total
overhead amount of ozone is depleted during the
Antarctic spring. In the Arctic Polar Regions a
similar but smaller hole has appeared in 6 out of
the last 9 years. Increases in surface UV-B
radiation have been observed in association with
local decreases in stratospheric ozone, from both
ground-based and satellite-borne instruments.
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A dobson unit is the most basic measure used in
ozone research.One Dobson Unit (DU) is defined to
be 0.01 mm thickness at STP (standard temperature
and pressure). Ozone layer thickness is expressed
in terms of Dobson units, which measure what its
physical thickness would be if compressed in the
Earth's atmosphere.
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Ozone-depleting compounds are a group of
chemicals called halocarbons that can contain the
elements chlorine, fluorine, bromine, carbon, and
hydrogen. As early as 1974 an article in
Nature11 had shown that compounds being added to
the Earths atmosphere were destroying the ozone
layer. One group of halocarbons called
chlorofluorocarbons (CFCs) invented in 1928 found
use in aerosols, foams, refrigeration, air
conditioners, cleaning of electronic components,
and as a solvent. Another group (halons) was used
in fire extinguishers. Once released,
halocarbons are long-lived and stable chemicals
that rise up and persist in the stratosphere for
many years, where they break down ozone.
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Policy response on Ozone depletion The UN started
to address the problem in the 1970s, resulting in
the 1987 Montreal Protocol on Substances that
Deplete the Ozone Layer. The Protocol aims to
reduce and eventually eliminate the emissions of
man-made ozone depleting substances, by stopping
their production and use, and has been modified
or strengthened five times so far by amendments.
As more culprit depleting substances are
identified, the scope of the Protocol has been
expanded.
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The UN Secretary General said in September 2000
that without the Protocol, the levels of
ozone-damaging substances would have been five
times higher than they are today, but developing
countries are yet to phase out CFC emissions to
meet the 2010 deadline imposed by the Montreal
Protocol. There are also reports of a black
market in CFCs. According to a recent UNEP news
release, scientists predict that the ozone layer
will fully recover some time in the 21st century
but only if the Protocol continues to be
vigorously enforced.
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Acid Rain
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Introduction to acid rain

• Normal rain water is always slightly acidic
  because CO2 present in atmosphere. get dissolved
  in it form carbonic acid. Normal acidity of rain
  water is 5.6
• H2O (l) CO2 (g) H2CO3 (aq)
• Because of SO2 NO2 gases as pollutants in
  atmosphere.
• The pH of rain is further lowered to as 2.4
  this type of
• Precipitation is called as ACID RAIN.
• Acid rain is combination of H2SO4, HNO3 and HCl
  is third

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History

• Since industrial revolution, emissions of SO2
  NO2 in atmosphere have increased.
• In 1852 ROBERT ANGUS SMITH was first to show
  relation b/w acid rain atmosphere pollution in
  Manchester (England)
• Term acid rain was generated by SMITH in 1972.
• Problem of acid rain has not only increased with
  population industrial growth but has become
  widespread.

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Acid Rain Formation

• Emissions of sulfur dioxide and nitrogen oxides
  react with water vapor in the atmosphere to
  create sulfuric and nitric acids.

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Causes Of Acid Rain

• NATURAL CAUSES-
• Volcanic emissions.
• Biological processes.
• Lightning.
• ANTHROPOGENIC CAUSES-
• Factories (industrialization)
• Motor vehicles, automobile exhaust.
• Coal based power plants.
• Domestic fires.
• Smelters.

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Measurement of acid rain

• Acid rain is measured through pH tests that
  determine the concentration of hydrogen ions in a
  liter of fluid. The pH (potential for hydrogen)
  scale is used to measure acidity or alkalinity.
  It runs from 0 to 14. (The greater the
  concentration of hydrogen ions and the lower the
  pH number, the more acidic a substance is the
  lower the concentration of hydrogen ions and the
  higher the pH number, the more alkalineor
  basica substance is.) So a pH greater than 7
  indicates an alkaline substance while a pH less
  than 7 indicates an acidic substance

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Chemical Processes Involved In acid rain

• Formation Of Sulphuric Acid
• S O2 SO2
• SO2 1/2O2 H2O H2SO4
• Reaction Involving Formation Of Nitric Acid
• NO O3 NO2O2
• NO2 O3 NO3O2
• NO3 NO2 N2O5
• N2O5 H2O 2HNO3

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Adverse Effect Of Acid Rain

• Plants
• Effects plants and trees.
• Causes yellowing of leaf tissue (chlorosis).

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• Direct effect on plant growth due to toxification
  of soil
• It takes away soil nutrients causing stunted
  growth.
• Block stomatal pores of leaves.
• Electron transport system, biochemical reactions
  dominated by pH are effected.
• Degradation of plant chlorophyll.

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b. Soil

• Acid rain damages soil biology and chemistry
• Microbes not able to tolerate low pH and die
• Upper fertile layer of soil is affect as
  essential nutrients are leached away from soil

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• Surface Water And Aquatic Animals
• Acid rain causes lower pH high aluminum conc.
  in surface water that causes damages to fish and
  aquatic animals.
• Biodiversity of water body is reduced.
• Lakes, rivers are fragile ecosystems where each
  species depend on other to survive ,if one
  disappears other too disappears.

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c. Human Health

• Aerosol mist of sulfuric acid has very serious
  respiratory effects.
• Acidification play havoc with human nervous
  system ,respiratory system and digestive system.

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e. Effect On Buildings

• Causes extensive damage to buildings, structural
  materials of marble ,limestone, slate etc.
• CaCO3H2SO4? CaSO4H2OCO2
• In Greece and Italy invaluable stone statues have
  been partially dissolved by acid rain.
• Taj Mahal in Agra is also suffering due to acid
  fumes from Mathura refinery.

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Deterioration of Taj Mahal

• Taj, the seventh wonder of world getting
  deteriorated because of emissions of Mathura oil
  refinery which lies 40 km away from Taj
• The oil refinery emits 25-30 tones of SO2 daily
  in spite of using low sulphur fuels.

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Control measures

• Clean combustion technologies
• Using pollution control equipments
• Replacement of coal by natural gas or renewable
  energy resources
• Liming of lakes and soils
• Formulate the policy framework for reduction of
  sulfur dioxide and other acid rain causing gas
  emissions.
• Support a set of subproject that promote cleaner
  production, reduce acid rain and air pollution,
  improve the environment.

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Soft (Bituminous) Coal
This is coal that has a low sulfur content.
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Liming
The process of adding a lime or calcium hydroxide
(a base) to acidified lakes.
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Use Energy Sources that Dont Produce Nitrogen or
Sulfur Oxides
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Health Effects of Air Pollution
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Air Pollution

• The Clean Air Act requires EPA to set National
  Ambient Air Quality Standards (NAAQS) for six
  common air pollutants (also known as criteria
  air pollutants"). 
• These pollutants are found all over the U.S.,
  some from natural sources and some from man-made
  sources.
• They can harm your health and the environment,
  and cause property damage.

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Criteria Air Pollutants

• carbon monoxide
• lead
• ground-level ozone
• particulate matter
• nitrogen dioxide
• sulfur dioxide

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Carbon Monoxide

• Incomplete oxidation of carbon results in the
  production of carbon monoxide.
• Natural CO formation occurs from photochemical
  reactions in the troposphere, volcanoes, forest
  fires, etc.
• Breathing air with a high concentration of CO
  reduces the amount of oxygen that can be
  transported in the blood stream to critical
  organs like the heart and brain.
• At very high levels, which are possible indoors
  or in other enclosed environments, CO can cause
  dizziness, confusion, unconsciousness and death.

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Lead

• As a result of EPA's regulatory efforts including
  the removal of lead from motor vehicle gasoline,
  levels of lead in the air decreased by 98 percent
  between 1980 and 2014.

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Lead

• Once taken into the body, lead distributes
  throughout the body in the blood and is
  accumulated in the bones. 
• Depending on the level of exposure, lead can
  adversely affect the nervous system, kidney
  function, immune system, reproductive and
  developmental systems and the cardiovascular
  system. 
• Lead exposure also affects the oxygen carrying
  capacity of the blood. 

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Ozone

• Breathing ozone can trigger a variety of health
  problems, particularly for children, the elderly,
  and people of all ages who have lung diseases
  such as asthma.
• Ground level ozone can also have harmful effects
  on sensitive vegetation and ecosystems.

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Ozone
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Particular Matter

• EPA groups particle pollution into two
  categories
• "Inhalable coarse particles," such as those found
  near roadways and dusty industries, are larger
  than 2.5 micrometers and smaller than 10
  micrometers in diameter.
• "Fine particles," such as those found in smoke
  and haze, are 2.5 micrometers in diameter and
  smaller. These particles can be directly emitted
  from sources such as forest fires, or they can
  form when gases emitted from power plants,
  industries and automobiles react in the air.

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Particulate Matter
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Particulate Matter

• Particulate matter contains microscopic solids or
  liquid droplets that are so small that they can
  be inhaled and cause serious health problems.

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Nitrous Oxides

• Breathing air with a high concentration of
  NO2 can irritate airways in the human respiratory
  system.
• Such exposures over short periods can aggravate
  respiratory diseases, particularly asthma,
  leading to respiratory symptoms (such as
  coughing, wheezing or difficulty breathing),
  hospital admissions and visits to emergency
  rooms.
• Longer exposures to elevated concentrations of
  NO2 may contribute to the development of asthma
  and potentially increase susceptibility to
  respiratory infections. People with asthma, as
  well as children and the elderly are generally at
  greater risk for  the health effects of NO2.
• NO2 along with other NOx  reacts with other
  chemicals in the air to form both particulate
  matter and ozone. Both of these are also harmful
  when inhaled due to effects on the respiratory
  system.

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Sulfur Oxides

• The largest source of SO2 in the atmosphere is
  the burning of fossil fuels by power plants and
  other industrial facilities.
• Smaller sources of SO2 emissions include
• industrial processes such as extracting metal
  from ore
• natural sources such as volcanoes
• and locomotives, ships and other vehicles and
  heavy equipment that burn fuel with a high sulfur
  content.    

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Sulfur Oxides

• At high concentrations, gaseous SO2 can harm
  trees and plants by damaging foliage and
  decreasing growth and can contribute to acid rain
  which can harm sensitive ecosystems. 
• Short-term exposures to SO2 can harm the human
  respiratory system and make breathing difficult.
  Children, the elderly, and those who suffer from
  asthma are particularly sensitive to effects of
  SO2.