Major Air Pollutants: Part 1 Carbon Oxides, Sulfur Oxides, and Particulates

During the 1950’s and 1960’s, most factories looked like this

17_15b.JPG Figure 17-15b Title: Industrial smog. Caption: Under certain weather conditions, industrial smog can blanket whole towns or regions, as it did in Donora, Pennsylvania, shown here in the daytime during its deadly 1948 smog episode (b). Notes: Keywords: atmosphere, air pollution, pollutants, industrial smog, sulfur dioxide, acid precipitation, rain, carbon dioxide, carbon monoxide, greenhouse gases, climates, global warming, energy resources, fossil fuels, nonrenewable, coal, oil

What is industrial smog? Industrial smog is a mixture of sulfur dioxide, droplets of sulfuric acid, and a variety of suspended solid particles emitted mostly by burning coal.

There are six criteria of air pollutants established by the EPA Carbon Oxides Sulfur Oxides Nitrogen Oxides Ozone (at ground level) Particulate matter Lead

17_12.JPG Figure 17-12 Title: Emission of the six major pollutants. Caption: In 2006, the United States emitted 137 million tons of the six major pollutants whose emissions are monitored by the EPA and state and local agencies. Carbon monoxide accounted for most of these emissions, by mass. Data from U.S. EPA. Notes: Keywords: atmosphere, air pollution, criteria pollutants, carbon monoxide, nitrous oxides, sulfur dioxide, particulates, lead, ozone

17_11.JPG Figure 17-11 Title: EPA's national ambient air quality standards. Caption: Roughly 122 million Americans live in counties that in 2005 failed to meet the EPA's national ambient air quality standards (NAAQS) for at least one criteria pollutant. This map shows counties that failed to attain the standards for one (green) through four (red) of the six criteria pollutants. Data from U.S. EPA. Notes: Keywords: atmosphere, air pollution, criteria pollutants

Major Air Pollutants Sulfur dioxide (SO2) and sulfuric acid: About one-third of SO2 in the troposphere occurs naturally through the sulfur cycle. Two-thirds come from human sources, mostly combustion (S+ O2  SO2) of sulfur-containing coal and from oil refining and smelting of sulfide ores.

How the Sulfur Found in Coal and Oil turns into air pollution: S + O2 = SO2 (Primary Air Pollutant) 2SO2 + O2 = 2SO3 (Secondary Air Pollutant) SO3 + H2O = H2SO4 (Sulfuric Acid – Acid Rain)

17_15a.jpg Figure 17-15a Title: Industrial smog. Caption: Emissions from the combustion of coal and oil in manufacturing plants and utilities without pollution-control technologies can create industrial smog. Industrial smog consists primarily of sulfur dioxide and particulate matter, as well as carbon monoxide and carbon dioxide from the carbon component of fossil fuels. When fossil fuels are combusted, sulfur contaminants give rise to sulfur dioxide, which in the presence of other chemicals in the atmosphere can produce several other sulfur compounds (a). Notes: Keywords: atmosphere, air pollution, pollutants, industrial smog, sulfur dioxide, acid precipitation, rain, carbon dioxide, carbon monoxide, greenhouse gases, climates, global warming, energy resources, fossil fuels, nonrenewable, coal, oil

Major Air Pollutants Carbon oxides: Carbon monoxide (CO) is a highly toxic gas that forms during the incomplete combustion of carbon-containing materials. 93% of carbon dioxide (CO2) in the troposphere occurs as a result of the carbon cycle. 7% of CO2 in the troposphere occurs as a result of human activities (mostly burning fossil fuels). California has now classified Carbon Dioxide as an air pollutant and is taking action to reduce its production

Discussion Question Are you willing to pay more for energy and the things that you buy in order to help reduce carbon dioxide levels?

17_10b.jpg Figure 17-10b Title: Natural air pollution. Caption: Volcanoes are another, as shown by Mount Saint Helens (b), which erupted in the state of Washington in 1980. Notes: Keywords: atmosphere, air pollution, pollutants, volcanoes, volcanic eruptions

17_10c.JPG Figure 17-10c Title: Natural air pollution. Caption: A third cause is fires in forests and grasslands (c). Often, pollution from natural sources is made worse by human influence, such as when poor agricultural practices lead to soil erosion by wind, or when fire suppression leads to more devastating fires. Notes: Keywords: atmosphere, air pollution, pollutants, wildfires

Major Air Pollutants Suspended particulate matter (SPM): Consists of a variety of solid particles and liquid droplets small and light enough to remain suspended in the air. The most harmful forms of SPM are fine particles (PM-10, with an average diameter < 10 micrometers) and ultrafine particles (PM-2.5). According to the EPA, SPM is responsible for about 60,000 premature deaths a year in the U.S.

This instrument monitors the amount of particulate pollution in the air in micrograms per cubic meter

Factors Influencing Levels of Outdoor Air Pollution Outdoor air pollution can be reduced by: settling out, precipitation, sea spray, winds, and chemical reactions. Outdoor air pollution can be increased by: urban buildings (slow wind dispersal of pollutants), mountains (promote temperature inversions), and high temperatures (promote photochemical reactions).