CE2308 AIR POLLUTION MANAGEMENT_NoRestriction_NoRestriction.pdf. CE2308 AIR POLLUTION MANAGEMENT_NoRestriction_NoRestric
UNIT I AIR POLLUTION Transfer of harmful and/or of Natural/Synthetic materials into the atmosphere as direct/indirect consequences of human activity.
Types of Air Pollution •
Personal air exposure -It refers to exposure to dust, fumes and gases to which an individual exposes himself when he indulge himself in smoking
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Occupational air exposure -It represents the type of exposure of individuals to potentially harmful concentration of aerosols, vapors, and gases in their working environment.
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Community air exposure
-This is most serious, complex, consists of varieties of assortment of pollution sources, meteorological factors, and wide variety of adverse social, economical, and health effects. Sources of air pollution
So Natural Sources –Volcano, forest fire, dust storms, oceans, plants and trees •
Anthropogenic Sources - created by human beings
-Stationary sources u
Atmosphere
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It is a mixture of gases that forms a layer of about 250 miles thick around the earth. - Bottom 10-12 miles (Troposphere) is most important part in terms of
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Weather Other aspects of Biogeochemical cycle
- The lowest 600 meters of Troposphere: Air Quality Studies
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Composition of Air - 78% nitrogen, 21% oxygen, 1% carbon dioxide, water, other gases
Divided into four zones: - Troposphere - Stratosphere - Mesosphere - Thermosphere
Source of Air Pollution • •
Natural Sources –Volcano, forest fire, dust storms, oceans, plants and trees Anthropogenic Sources - created by human beings -Stationary sources
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Point sources (Industrial processing, power plants, fuels combustion etc.) Area sources (Residential heating coal gas oil, on site incineration, open burning etc.)
- Mobile sources
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Line sources (Highway vehicles, railroad locomotives, channel vessels etc.)
Air Pollutants Any substance occurring in the atmosphere that may have adverse effects on humans, animals, plant life, and/or inanimate materials.
Air pollutants have known or suspected harmful effects on human health and tironment.
Criteria Air Pollutants • •
Based on health effects with measured air quality levels that violate the National Ambient Air Quality Standards (NAAQS) (NAAQS) -CO -NOx -SOx -VOCs -Particulates -Pb
Hazardous Air Pollutants • •
Predecessor: National Emission Standards for Hazardous Air Pollutants (NESHAPs) Clean Air Act Amendments of 1990 directed EPA to establish emission controls for 189 chemicals listed in the Act. -NOT based on health criteria -Based on Maximum Achievable Control Technology (MACT)
Non-Criteria Pollutants • •
In essence, all pollutants not included in the NAAQS and HAP lists Examples: -CO -NaCl
Air Pollutants
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Primary air pollutants - Materials that when released pose health risks in their unmodified forms or those emitted directly from identifiable sources.
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Secondary air pollutants - Primary pollutants interact with one another, sunlight, or natural gases to produce new, harmful compounds
Primary Air Pollutants •
Five major materials released directly into the atmosphere in unmodified forms. -Carbon monoxide -Sulfur dioxide -Nitrogen oxides -Hydrocarbons -Particulate matter
Carbon Monoxide •
Produced by burning of organic material (coal, gas, wood, trash, etc.)
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Automobiles biggest source (80%)
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Cigarette smoke another major source
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Toxic because binds to hemoglobin, reduces oxygen in blood
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Not a persistent pollutant, combines with oxygen to form CO2
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Most communities now meet EPA standards, but rush hour traffic can produce high CO levels
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Not a persistent pollutant, combines with oxygen to form CO2
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Most communities now meet EPA standards, but rush hour traffic can produce high CO levels
Sulphur Dioxide
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Produced by burning sulfur containing fossil fuels (coal, oil)
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Coal-burning power plants major source
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Reacts in atmosphere to produce acids
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One of the major components of acid rain
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When inhaled, can be very corrosive to lung tissue
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London -1306 banned burning of sea coal -1952 “killer fog”: 4,000 people died in 4 weeks o tied to sulfur compounds in smog
Nitrogen Oxides
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Produced from burning of fossil fuels
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Contributes to acid rain, smog
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Automobile engine main source
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New engine technology has helped reduce, but many more cars
Hydrocarbons •
Hydrocarbons - organic compounds with hydrogen, carbon
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From incomplete burning or evaporated from fuel supplies
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Major source is automobiles, but some from industry
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Contribute to smog
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Improvements in engine design have helped reduce
Particulates
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Particulates - small pieces of solid materials and liquid droplets (2.5 mm and 10 mm)
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Examples: ash from fires, asbestos from brakes and insulation, dust
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Easily noticed: e.g. smokestacks
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Can accumulate in lungs and interfere with the ability of lungs to exchange gases.
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Some particulates are known carcinogens
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Those working in dusty conditions at highest risk (e.g., miners)
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Respirable Suspended Particulate Matter (RSPM) -PM1 having size
