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Air Pollution . Causes, Effects, and Solutions. Terms to be familiar with…. CAA – Clean Air Act CO – carbon monoxide NOx – nitrogen dioxide and nitrogen oxides PM – Particulate Matter SOx – Sulfur dioxide and sulfur oxides VOC’s – Volatile Organic Compounds. Our Atmospheric Composition.
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Air Pollution Causes, Effects, and Solutions
Terms to be familiar with… • CAA – Clean Air Act • CO – carbon monoxide • NOx – nitrogen dioxide and nitrogen oxides • PM – Particulate Matter • SOx – Sulfur dioxide and sulfur oxides • VOC’s – Volatile Organic Compounds
Air Pollution Air Pollution Control Act of 1955 1st federal air pollution law 1960s - Clean Air Act of 1963 • (Emissions standards set for stationary sources such as power plants and steel mills) 1970 – The Clean Air Act (CAA) of 1970 • EPA was formed to enforce air pollution laws (change in national policy from advisor to enforcer) – Six major air pollutant types 1990 – The Clean Air Act of 1990 • Clean Air Act of 1970 is re-written and new titles established
Six Common Air Pollutants • Particulate Matter • Carbon monoxide • Nitrogen dioxide • Lower Troposphere OZONE producing activities • Sulfur dioxide • Lead The EPA asked to Obama Administration to consider Carbon dioxide as a new common air pollutant. Source: U.S. Environmental Protection Agency- July 19, 2011
Particulate Matter (PM) • It is known as “Particle Pollution” and can range in sizes and effects on humans • Particle sizes: • 10 um (diameter) greater health threat than “Course particles” found near roadways and in mining and concrete industries.
Carbon monoxide (CO) • CO is a colorless-odorless gas produced by the incomplete combustion of fossil fuels. • Motor vehicle exhaust contributes to 56% of the CO produced in the U.S. • Over 20% comes from other engines, boats and equipment not on-road.
CO Pollution EPA : 1999 Data
Updated On 11/30/2011, Published on 12/27/2011 Environmental Epidemiology Program, Bureau of Epidemiology, Division of Disease Control and Prevention, Utah Department of Health, Salt Lake City, UT 84114-2104
Nitrogen dioxide (NOx) • Generic term for multiple combinations of nitrogen and oxygen • Colorless and odorless but sometimesNO2 can be seen as a brown-red gas • Sources include motor vehicles, electric utilities, industry, and commercial and residential fossil fuel usages.
NOx is Alarming • Contributes to the formation of acid rain • Can contribute to nutrient load that affects water quality • Contributes to Global Warming (traps long wave radiation on Earth) which becomes Thermal Radiation.
Los Angeles California: the smog is the brown layer in the picture Source: http://www.city-data.com/picfilesv/picv8898.php
New York city picture: This 1963 photo shows a massive smog episode in New York City. (Photo: AP/Wide World Photo, EPA Journal Jan/Feb 1990.
OZONE • It is not usually emitted directly into the air, but at ground level is created by a chemical reaction between oxides of nitrogen (NOx) and volatile organic compounds (VOC) in the presence of sunlight. • Sunlight and hot weather cause ground-level ozone to form in harmful concentrations in the air.
Good Good Ozone is “Bad” Here
Ozone There are two forms of Ozone. The Ozone that limits UV rays from reaching the Earth is in the Stratosphere (10 – 30 miles above the Earth’s surface. The “Bad” Ozone is in the lower Troposphere.
Sulfur dioxide (SOx) • Common in raw materials like coal, ore, and crude oil. • Over 65% of SO2 released to the air, or more than 13 million tons per year, comes from electric utilities, especially those that burn coal.
SOx emission Source: http://www.epa.gov/air/urbanair/so2/what1.html
Acadia, ME Big Bend, TX Bryce Canyon, UT
Lead • These emissions have been phased out in the U.S., but NOT globally. • The major sources TODAY are smelters, waste incinerators, utilities and lead-acid battery manufacturers.
Notice the change in lead emission sources since the banning of lead fuel use in the early 1980’s in the U.S. Source: http://www.epa.gov/air/urbanair/lead/what.html
Lead Concerns • Affects young children and infants more • Is still found at high levels in urban and industrial areas • Deposits are in soil and water and harms animals and fish
Air Pollution Health Impacts Air Pollutant Respiratory Other Particulate Matter Yes Limited Carbon monoxide Yes Neurologic Nitrogen oxides Yes Limited Ozone Yes Limited Sulfur oxides Yes Limited Lead Limited Organ/Neuro
Solutions to Industrial Emissions • Wet Scrubbers • Baghouse (Venturi) Filters • Electrostatic Precipitators • Cyclone Separators
Wet Scrubbers • The purge stream, which contains the particulate and sulfur oxides removed from the flue gas, may either be treated in the refinery's existing wastewater treatment system or may be treated in a dedicated PTU (Purge Treatment Unit).
Cyclone Separators • Cyclone dust collectors have been used as a pre-filter before a cartridge or baghouse collector, • Effective for larger, more abrasive dust particles that can easily damage standard media filters.
Baghouse filter • "Baghouse" is an example of surface filtration • "Filter" is a membrane (sheet steel, cloth, wine mesh, or filter paper) with holes smaller than the particles. • It is usually the cake on the filter that stops particles from flowing through
Electrostatic Precipitators • Electrostatic precipitators have collection efficiency of 99%, but do not work well for flyash with a high electrical resistivity (as commonly results from combustion of low-sulfur coal). Flyash is a common emission from the burning of fossil fuels
Indoor Pollutants VOCs Solvents (common) from paints, etc VOC’s (emitted from dishwashers) Over-insulated homes can cause pollutants to be held indoors Poorly maintained heating systems
What’s up with Carbon dioxide? Is it the cause of Global Warming? “Global Climate Change”