1. Air Pollution

2. Essential Question
What causes air pollution?

3. Enduring Understandings
Air pollution can come in many forms and is caused by natural as well as human processes.

4. Review Layers of the atmosphere Troposphere Stratosphere Mesosphere
Thermosphere
Exosphere

5. Review Atmosphere Nitrogen 78% Oxygen 21% Other 1% Argon 0.9%
CO %
CH %
NOx %
O %

6. All right, enough review…. On to the new stuff!

7. Air Pollution
Condition in which the air contains harmful substances at unhealthy levels

8. Air Pollution
Condition in which the air contains harmful substances at unhealthy levels

9. Air Pollution
Condition in which the air contains harmful substances at unhealthy levels

10. Human Sources Fossil Fuels Transportation Electricity Generation
Oil
Electricity Generation
Coal
Construction
Agriculture
Industry

11. Bhopal India Dec. 2, 3 1984 27 tons methyl isocyanate
3,000-20,000 deaths

12. Natural Sources
Volcanoes
Pollen and Spores
Dust

14. Primary Pollutant
A pollutant that enters the atmosphere as a direct result of human activity
CO2 CO
SO2
NOx
VOCs PM

15. Primary Pollutant CO – Carbon Monoxide Odorless Colorless
Combustion of fossil fuels
Interferes w/ blood’s ability to carry oxygen
Drowsiness
Death

16. Primary Pollutant NOx – Nitrogen Oxides
High temp combustion of fossil fuels
Transportation
Industry
Acid Rain
Smog
Respiratory Infections
Cancer

17. Primary Pollutant SO2 – Sulfur Dioxide
Burning of what else? fossil fuels
Refineries
Coal Burning Power Plants
Acid Rain
Respiratory Ailments
Damaging to Plant Life

18. Primary Pollutant VOC – Volatile Organic Compounds
Burning of fossil fuels
Paints
Offgasing of plastics and vinyls
New car smell
Smog
Cancer
Fry your brain

19. Primary Pollutant PM – Particulate Matter Tiny Solids or liquids Smoke
Hydrocarbons
Construction
Agriculture
Acid Rain
Respiratory Problems
Cancer

20. Secondary Pollutants
A pollutant that results from a primary pollutant chemically reacting with another primary pollutant or naturally occuring substance.

21. Secondary Pollutants O3 – Ozone H2SO4 (Sulfuric Acid)
HNO3 (Nitric Acid)
Acid Rain

22. Pollution from Cars 1/3 of all pollution from transporation
234,852,000 registered vehicles
3,982,000 miles of roadway
2,600,000,000,000 miles driven
90% from passenger cars
Source: U.S. Census Bureau 2004

23. How is gasoline derived from oil?
Crude oil (petroleum) is made of hydrocarbons
Hydrocarbon = Hydrogen + Carbon
Also Sulfur, Nitrogen, Oxygen, Metals, Salts
Hydrocarbons contain a lot of energy!
Crude oil is refined (distillation) to separate out different hydrocarbons

24. Products made from oil
Clothing Ink Heart Valves Crayons Parachutes Telephones
Deodorant Pantyhose
Carpets
Motorcycle helmets Pillows Shoes Toilet seats Movie film Credit cards Aspirin Golf balls Sunglasses Fishing rods Soft contact lenses Shaving cream Footballs

25. More Products made from petroleum
Tires Toothbrushes Toothpaste Lipstick Eyeglasses Ice chests Life jackets TV cabinets Car battery cases Refrigerants
Artificial Limbs Dentures Ballpoint pens Boats Nail polish Curtains Vitamin capsules Skis Insecticides Perfumes Petroleum jelly Food preservatives

26. Exhaust Emissions Combustion: “Perfect” Combustion Typical Combustion
Hydrocarbons in fuel mix with oxygen
14.7:1 Stoichiometric
“Perfect” Combustion
Fuel + Air = CO2 + H2O + N2
Typical Combustion
Fuel + Air = HC + NOx + CO + CO2 + H2O

27. Exhaust Pollutants Hydrocarbons (HC)
Result of incomplete burning of fuel
Component of smog
Particulate Matter
Black Stuff

28. Exhaust Pollutants
NOx CO
CO2

29. Catalytic Converter Part of exhaust system
Convert harmful pollutants to less harmful emissions
HC H2O
CO CO2
NOx  N2

30. Reduction Catalyst
2NO => N2 + O2 or 2NO2 => N2 + 2O2

31. Oxidation catalyst
2CO + O2 => 2CO2

32. Drawbacks to Catalytic Converters
Platinum
Only works at high temperatures

33. Evaporative Emissions
Occur when fuel evaporates before it is burned

34. Evaporative Emissions
Diurnal
Evaporation increases as temperature increases

35. Evaporative Emissions
Running Losses
Engine and exhaust vaporize fuel while car is running

36. Evaporative Emissions
Hot Soak
Engine remains hot after car is turned off and fuel continues to evaporate

37. Evaporative Emissions
Refueling
Fuel vapors are forced out of tank when displaced by fuel

38. Reducing Pollution from Cars
Avoid unnecessary driving
Consolidate trips
Plan errands
Car pool
Share a ride
Bike or Walk

39. Reducing Pollution from Cars
Maintain your car
Extend Life
Increase resale value
Better gas mileage
Change oil, filters, belts, fluids
Tires inflated
Octane

40. Reducing Pollution from Cars
Idling
Stop and Go driving
Air conditioning
High Engine Loads
Cold temperatures
Refueling