Air Pollution Essay Research Paper Air PollutionIntroductionAir

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Air Pollution Essay, Research Paper Air Pollution Introduction Air pollution is nothing new. Ever since the discovery of fire, less-than-desirable substances have been vented into the air. One of the first air-pollution regulations dates back to the fourteenth century, when King Edward I banned the burning of sea coal in lime kilns. U.S. air-pollution regulations have their roots in British Common Law. But regardless of those efforts, air pollution continues to be a serious local and world-wide problem. Pollution is the pressure within the air of one or more substances that are harmful to human health, welfare, animal or plant life, or property. In the past with air pollution we included mainly the outdoor pollutants, although in recent years this is not the case. Today we

separate pollutants in to two categories. Primary pollutants, because they come directly from various sources, and secondary which are by-products of chemical interactions of the primary pollutants within the atmosphere. Particulates Although air pollution might be thought of as unwanted gases in the atmosphere, two of five primary pollutants are really solid substances called particulates. Soot has always been a sure indicator of a polluted atmosphere, but other than soiling and a negative psychological effect, soot can’t settle into the lungs and cause serious diseases. Thick ,black smoke coming out of a stack is that what we think causes the pollution, but what really creates the damage is what we can’t see. Particles like this are called suspended particles. They come

from many incomplete burning and can consist a variety of substances. The most harmful type of particulate is so small that that it is microscopic. All the particulates are harmful for several reasons. When inhaled, they can damage the interior of the lung; they can also be poisonous. Sometimes gases will glue to their surfaces and in a process called adsorption they can reach the lungs. All these particles are mainly products of combustion. The major sources include industrial processes, power plants that are both coal and oil-fired, residential heating, and transportation. But coal burning is the greatest source. Table 1 below shows estimates of U.S. particulate emissions from various sources. TABLE 1 National U.S. Emissions Estimates-1990 (Million metric tons/year) SOURCE

PARTICULATES SULFUR OXIDES CARBON MONOXIDES Transportation Highway 1.3 0.6 30.3 Aircraft 0.1 0 1.1 Rail&Sea 0 0.3 1.9 Off-Highway equipment 0.1 0.1 4.4 TOTAL 1.5 1 37.7 Stationary fuel combustion Electric utilities 0.4 14.2 0.3 Indusrial furnaces 0.3 2.3 0.7 Commercial 0 0.4 0.1 Residential 1 0.3 6.4 TOTAL 1.7 17.2 7.5 Industrial processes 2.8 3.1 4.7 Solid waste disposal 0.3 0 1.7 Miacellaneous Forest fires 1.1 0 8.1 Other burning 0.1 0 0.6 Misc. Organic solvents 0 0 0 TOTAL 1.2 0 8.7 OVERALL TOTAL 7.5 21.3 60.3 Only 13% of the total is generated by transportation. Industrial sources account for nearly three times as much as 37%. Fires account for just about as much particulate emissions as transportation. That amount is matched by combustion from sources, which include the

generation of all heat and electricity. Emissions When coal was the main source to generate energy, power plants and homes accounted for much greater contribution. The switch to oil and nuclear power has lowered those concentrations, but it hasn’t been without its own problems. In addition to health-related problems, particles can damage materials through corrosion and erosion, as well as soiling. Particles can also impact the weather, through changes in visibility, and even in enhancing precipitation. Studies around major urban areas show an increase in precipitation and in thunderstorms with hail downwind from downtown areas. The weather modification is localizes but definite, and may be related to an increase in the large condensation nuclei that the particles provide. Lead