AIR POLLUTION

Primary vs Secondary Primary pollutants: enter atmosphere directly –Ex: CO 2, NO x, SO x, Particulates and Hydrocarbons Secondary pollutants: form due to chemical rxns occurring in air. – Ex: Trop. Ozone & Acid Rain

Case Study: Acid Rain Secondary Pollutant: Sulfuric Acid, H 2 SO 4 SO 2 + H 2 O  H 2 SO 4 Burning coal Reduces crop yields, irritates lungs

Effects of Air Pollution Damages lungs and reduces visibility Corrodes materials Contributes to global warming, acid rain, and ozone depletion Bangkok Popo

Little Kids More Susceptible… Higher metabolisms… Lungs are still developing…

Burning Fossil Fuels Causes most air pollution  energy Fossil fuel: fuel formed in earth from ancient plant /animal remains. Ex’s: coal, oil, natural gas

Benxi: Pollution from steel mills blows over residential buildings

Controlling Air Pollutants Burn < Fossil Fuels!

…By using alternative energy sources

Wet Scrubb er - - mix liquid w/ air pollutant  pollutant sinks w/ liquid.

Electrostatic Precipitator Give air pollutants a charge  stick to negative plate  wipe plate clean

Catalytic Converter Reduces emissions from combustion engines 3 tasks: A) take CO  CO 2 B) Take NOx  O 2 and N C) Take HCs  CO 2 and H 2 O

Its required by the law!!!….unless your car is older than 1973

Clean Air Act of 1970 Set air quality standards for primary & secondary pollutants Established “criteria pollutants”- human DANGER States must develop clean air plans and test cars! Bush signs ‘90 amendment for NAAQS

Particulate Matter AKA aerosols: dust, lead, asbestos, salt, ash Enters by: hair, skin, gas, fire retardant, volcanoes – A– A– A– All eventually settle –R–R–R–Reduces amount of sun that reaches earth’s surface. Dust x 12000

Nitrogen Oxides (NO x ) –Damage: Inhibits plant growth, causes asthma, major cause of photochemical smog

NOx’s enters by: 1) combustion of gasoline from autos 2) fertilizer application 3) burning crop residues

Photochemical Smog Sun + NOx + Vol. Org Compounds (VOC’s)  Smog Smog PSA LA

Reacts in atmosphere  acid rain (H 2 SO 4 ) Irritates respiratory tracts; degrades metals & stone Sulfur Oxides (SOx)

–Enters by: Coal and oil burning for energy utilities –Can be taken out with calcium oxide (lime) after coal burning  flue gas desulfurization Sulfur Oxides (SOx)

CO, Carbon monoxide: poisonous, reduces red blood cells ability to carry O 2 CO 2 Carbon dioxide: adds to global warming Carbon Oxides (COx)

Enters: solid waste, fossil fuels (oil, natural gas, and coal), and wood are burned. Also, animal respiration. Carbon Oxides (COx)

Case Study: Lake Nyos Lake Nyos on top of magma in Cameroon. CO 2 leaks into the lake from magma. Huge CO 2 bubble released in Killed 1800 people and 3500 livestock. Cow suffocated

Case Study: Lake Nyos

Before and After

Highly volatile (unstable) compounds, cause cancer & contribute to global warming.Highly volatile (unstable) compounds, cause cancer & contribute to global warming. Hydrocarbons

Formed by: Engine combustion of fossil fuel, cow farts, wetland decompositionFormed by: Engine combustion of fossil fuel, cow farts, wetland decomposition Hydrocarbons

Major Air Pollutants Tropospheric ozoneTropospheric ozone –Secondary pollutant –NO 2 + light  NO + O –O + O 2  O 3 –Damage: coughing, inflammation of lungs.

Nature Helps Us! Gravity Rain and Snow Salty Sea Spray Winds Chemical Reactions  All Ways to Reduce Levels of Outdoor Air Pollution