CH08/chapter8.ppt

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Pollution from Energy Generation
and Energy Use
Air Pollution in Eastern Europe
Atmospheric Physics
Sources of Air Pollution
Air Quality Standards
Energy in the News
OPEC Price Changes
Lackner Lecture on Friday
Sustainable Energy Roundtable (Thursday)
Air Pollution in Eastern Europe
Trabant: East German car
Radioactive waste dumps in Moscow
Air pollution in Moscow
No information on health under communism
Copsa Mica, Romania; most polluted city in the world
Composition of Normal Air
Pollutants: parts of normal
Air that are added by humans
And are toxic to animals,
Vegetation or property
Two main components of
Air are…..
Air Pressure
We live at the bottom of an ocean
Of air.
Pressure = force per unit area
Pressure =mgh/area
Units of pressure=psi=lb per square
Inch OR newtons per square meter
1 Newton per square meter = 1 Pascal
(MKS system)
Air pressure changes as a function
Of elevation- How?
A Simple Barometer
Atmospheric Pressure
Although you can’t see it, the atmosphere exerts
Pressure on you
Examples:
1) suction cup holding a tile
2) glass of water upside down with paper on top
3) sucking water through a straw
Other examples?
A Barometer
Temperature Decrease with Elevation
PV=nRT (ideal gas law)
Pressure * Volume = number of moles * R * Temperature
If decrease pressure, what happens to temperature?
Adiabatic lapse rate: 7 degrees C per kilometer,
Or about 3.5 degrees F per thousand feet
Buoyant Force
A solid object will float if its density is equal to or less than the density
of the medium it is in.
So: light air rises and heavy air sinks.
What determines if air is light or heavy?
Normal Air Temperature Profile
Y axis:elevation
Elevation increases
Towards the top
X axis: temperature
Temperature increases
Towards the right
What do all profiles
Have in common?
Unusual Air Temperature Profile
X:Temperature
increasing
To right
Y: Elevation
Increasing
Towards the top
What is the
common
feature of
All of these
Temperature
Profiles?
Temperature Inversion
What you get when there is a hot layer
Of air on top of colder air.
Hot layer: lid that traps pollutants
Why?
Air Pressure Systems
Why does warm rising
Air produce lower
Pressures
Why does cold sinking air
Produce higher pressures?
Wind Systems
What are the pressure differences at ground level
Between a high pressure and low pressure system?
Global Wind Systems
Winds move pollutants
Which direction do they
Move pollutants
in the United
States (on average)?
Form of Air Pollutants
Aerosols: Small droplets of liquid suspended in a gas
What are common aerosols that you encounter? (3 or more)
Particulates: Small particles of solid material?
Examples of common particulates? (3 or more)
Does size of particulates matter? Why or why not?
Particulates can be charged: they are then more likely to
Adsorb other materials on their surfaces
Types of Pollutants
PM10- Particulate matter under 10 microns in size
PM2.5-Particulate matter under 2.5 microns in size
Carbon Monoxide-produced by incomplete combustion
Sulfur Oxides-from burning of fossil fuels and oxidation of sulfur.
Produce acid rain
Pb (plumbum or lead)-heavy metal, neurotoxin
Hg-(mercury)-also a heavy metal and neurotoxin
Nitrogen Oxides-from high temperature combustion,also source
Of acid rain
VOC-volatile organic compounds, also O3-Ozone
Biggest < 10 micron Particulate Sources
Power
Co.
2-6
8-9?
18
20-22
25
Coal
Mining
11
Non Attainment Areas PM10
Do
Industrial
Sources
Dominate
The
Emission
Of PM10
Why or
Why not?
Particulates:Why Size Matters
Smaller particulates can enter the lungs and remain there. All
particulate matter less than 10 microns in diameter can do this.
Separation of matter less than 10 microns and less than 2.5 microns
Is relatively new. Why? Difficult to measure size.
What diseases are caused directly and indirectly by small particulates?
(at least three)
Black Lung
Diseases
Produced by high
Concentrations
Of small particulate
matter:
Black lung (emphysema)
Asthma
Lung cancer
(Indirectly: congestive
Heart failure)
Trace Elements in Coal
Which trace elements are most dangerous?
Why?
Urban Particulates and Dust
Concentrations normalized to Al (that is Aluminum
Concentration is set to be 1.) This is because most common
weathering product of crustal weathering is clay.
All clay minerals are rich in Al. What dangerous elements are
Enriched by over 100 times?
Relative Contributions to City Dust
Minor constituents
Major constituents
Which are most surprising?
Sootprints
All carbon is not alike !!!
Gray:Carbon char
Dark aqua: Carbon ash
Purple:Carbon from gas turbine
Light Blue:Carbon from high pressure
Diesel engine
Red:Carbon from medium pressure
Diesel engine
Green: carbon from idling diesel engine
Dark Blue: amorphous carbon
Energy loss in electron volts: product
Of thermal history of carbon
Why is this work important?
Largest Pb Emission Sources
Power Co
Nos:
5-7
10
15
17
Others:
Steel
GE
Navy
Pb non attainment areas
Do
Industrial
Sources
Dominate
Pb
Emission?
Why or
Why Not?
Largest VOC Emissions Sources
Oil
Company
Nos:
Including
Refineries
2-4.6,
15,16,23
Electricity
9,18
Natural
Gas
10
VOC Sources
Oil Refineries
Cars
Methane from decay (also termites)
Aromatic compounds from trees= terpenes
e.g. pine, eucalyptus
Largest SO2 Emissions Sources
Power
Plant
Nos:
1-25
What
Fossil
Fuel
Do
These
Plants
Use?
Non Attainment Areas Sulfur Dioxide
Do
industrial
Sources
Dominate
SO2?
What
Else is
controlling
SO2
Pollution
Levels?
Sources of Sulfur Dioxide
Coal (sulfur content variable)
Volcanoes
Hydrogen sulfide gas from decay of organic matter
Oil (sulfur content variable)
Effects of Sulphur Dioxide on Health
At high exposure levels and/or longer durations of exposure
To sulphur dioxide:
1) airway resistance increases (harder to breathe)
2) health of bronchitis patients declines
3) number of hospital admissions increases
4) number of deaths from heart attacks increases
5) incidence of heart diseases increases
How Sulfur Oxides Produce Acid Rain
2SO2+O2= 2SO3
SO3+H2O=H2SO4
Sulfate Deposition
pH 2000
What areas have the highest pH in rain? Why?
pH 1994
Has there been improvement since 1994 in acid rain? Where?
Fish Populations in Adirondacks
What changes
Have occurred
In fish stocks?
Why?
(also geology)
(projections for
Future)
Largest NO2 Emission Sources
Power
Plant
Nos:
1-25
Are these
Old or
Modern
Plants?
Why?
How Nox and VOC Produce Smog
Photodissociation of NO2:
Light energy +NO2 = NO + O
O + O2 = O3
O3+NO = NO2 + O2
Ordinarily an equilibrium
Volatile organic compounds disturb this equilibrium
By producing organic radicals that are strong oxidizing
Agents. Result is SMOG.
Strong oxidizing agents:prevent the destruction of ozone
Therefore more ozone accumulates.
What would a strong reducer do?
Effect of Time of Day on
Pollutants (LA basin)
Why does ozone
Peak later in the day
than Nitric oxide and
Nitrogen dioxide?
Largest Carbon Monoxide Stationary Sources
Chemical
Plant
Nos:
5,10
16-18
22
(not all
Organic)
Others:
Steel
Paper
Aluminum
Non Attainment Areas: CO
Are
Industrial
Sources
Dominating
CO?
Why or
Why not?
Why do
western
States
Dominate?
Total Precipitation: 2000
Does rain
Wash CO
Out of the
Air?
Or it is
Legislative?
(gasoline
Additives
MTBE)
Mercury: Sources of Pollution
What is the best way to
Reduce the overall amount
Of Mercury pollution?
What does mercury do?
(Alice in Wonderland)
(methyl mercury)
Sources of Major Air Pollutants
What pollutants
Are dominated
By stationary
Sources?
By moving
Sources?
Indoor Air Pollutants
US National Air Quality Standards
Particulate Levels in Different Cities
Moscow (personal
Experience)
Truck drivers in Moscow
Russian truck and car
factories
Personally Imposed Pollution
Toxicity
Definitions:
Are they relevant
To these products?
More Personal Choices
New Silent Spring: Our Stolen Future by Theo Colbourn et al
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