LEAPES UNIT 7

Unit 7: Air Pollution - Stuff You Should Know

1. Identify and describe the pollution control measures and what specific pollutants each is used for.

Vapor Recovery Nozzle- Capture hydrocarbon VOCs released from gasoline fumes during refueling

Catalytic converter- filters out nitrogen oxides, carbon monoxide, and gasoline particles

Crushed limestone- used to reduce SO2 from coal power plants by mixing with coal before burning

Fluidized bed combustion- filters out sulfur dioxide by pumping in oxygen making combustion more efficient

Scrubbers- treats power plant emissions with chemicals which filter out NOx, So2, and VOCs (and PM in wet scrubbers)

Electrostatic precipitator- filters out particulate matter by charging particles and collecting the charged particles 

Fabric (baghouse) filters- filters out particulate matter

2. Describe the causes and effects of a thermal inversion

Layer of warm air overriding a layer of cool air at the surface.  Reduces dispersion of pollutants throughout the atmosphere which concentrates them at the surface, causing poor air quality

3. Identify the natural and anthropogenic sources of various air pollutants

Sulfur dioxide- natural: volcanic eruptions.  Anthropogenic: combustion of coal

Nitrogen oxides- natural: forest fires and lightning.  Anthropogenic: combustion of oil

Particulate matter- natural: forest fires, volcanic eruptions, dust storms.  Anthropogenic: combustion of coal or oil

Carbon dioxide- natural: decomposition, respiration, volcanic eruptions, forest fires.  Anthropogenic: combustion fossil fuels and deforestation

Carbon monoxide- anthropogenic: combustion of oil and natural gas

Ozone- natural: reaction of oxygen and sunlight in the stratosphere.  Anthropogenic: reaction of VOCs, nitrogen/sulfur oxides, and sunlight in the troposphere

Smog- anthropogenic: reaction of sunlight with VOCs and nitrogen/sulfur oxides

4. Provide examples of how to reduce the concentration of air pollutants into the atmosphere

Use less resources

Use energy more efficiently

Utilize the pollution control measures from #1

5. Explain the implications of the Clean Air Act and its amendments

Identified air pollutants that are now federally regulated.  This means that their emission is controlled and monitored that way their concentrations remain low

6. Identify the difference between primary and secondary pollutants

Primary pollutants are emitted directly into the air (from a smoke stack or tailpipe of a car).  

Secondary pollutants are created by a reaction between primary pollutants and sunlight or water

7. Describe the causes and effects of photochemical smog

Urban areas have more smog due to all of these factors

• More traffic → more NO₂

• Hotter temps due to low albedo of blacktop

• More VOCs due to gas stations & factories

• More electricity demand; more NO_x emissions from nearby power plants

Impacts

• Reduces sunlight; limiting photosynthesis

• O₃ damages plant stomata and irritates animal resp. tracts

• Resp. irritant; worsens asthma, bronchitis, COPD; irritates eyes

• Increased health care costs to treat asthma, bronchitis, COPD

• Lost productivity due to sick workers missing work or dying

• Decreased ag. yields due to less sunlight reaching crops & damage to plant stomata 

8. Describe the causes and effects of acid deposition

   1. Causes- reaction of primary pollutants (NOx and SO2) with water in the atmosphere

   2. Effects- soil/water acidification, leaching of metals out of soil and sediment (leads to toxic levels of things like aluminum)

9. Describe how acid rain can be an environmental problem away from the source and explain how it’s effects can be remediated

   1. Prevailing winds carry acid rain away from the source of pollution and degrade habitats further downwind (usually toward the East in the USA)

10. Describe the environmental impacts of noise pollution

    1. Can disrupt animal communication, predator-prey dynamics (predators can’t hear prey or prey can’t hear predators), migration paths, and disrupt organisms that use sonar to navigate or communicate

11. Describe the human health consequences of the following indoor air pollutants

    1. Radon- lung cancer

    2. VOCs- respiratory irritant

    3. Lead- neurotoxin, damages central nervous system especially in children

12. Describe the source of the following pollutants

    1. Radon- granite bedrock

    2. Mercury- burning coal

    3. Lead- burning oil or coal

    4. Arsenic- burning coal