Smokestacks were first used during industrial revolution between the 18th century and 19th centuries and were known to foul the airs in most larger cities but were most noted in large industrial centers like Manchester England or Pittsburgh Pennsylvania. During the dramatic growth and evolution of systems used to produce electricity coal burning central electric stations that relied on direct current were found throughout cities that released noxious fumes and soot into the city air. Taller smokestacks helped to reduce this environmental issue. During the 20th century fans were used to increase air currents needed in furnaces while heights that reached 1,300 feet grew as a way to comply with environmental safety regulations passed by governments.
Tall smokestacks--stacks of 500 feet or higher, which are primarily used at coal power plants--release air pollutants such as sulfur dioxide (SO2) and nitrogen oxides (NOx) high into the atmosphere to help limit the impact of these emissions on local air quality. Tall stacks can also increase the distance these pollutants travel in the atmosphere and harm air quality and the environment in downwind communities. The 1977 amendments to the Clean Air Act encourage the use of pollution control equipment over dispersion techniques, such as tall stacks, to meet national air standards. Section 123 of the Act does not limit stack height, but prohibits sources of emissions from using the dispersion effects of stack heights in excess of a stack's good engineering practice (GEP) height to meet emissions limitations. GAO was asked to report on (1) the number and location of tall stacks of 500 feet or higher at coal power plants and when they began operating; (2) what is known about such stacks' contribution to the interstate transport of air pollution and the pollution controls installed at plants with these stacks; and (3) the number of stacks that were built above GEP height since 1988 and the reasons for this. GAO analyzed Energy Information Administration (EIA) data on power plants, surveyed states with tall stacks, and interviewed experts on the transport of air pollution. GAO is not making recommendations in this report. The Environmental Protection Agency and the Department of Energy stated they had no comments on this report
smokestacks
By 2030 more than three quarters of the world's absolute poor are projected to live in Africa. Accelerating economic growth is key to rising incomes on the continent, and central to this challenge is establishing activities that are capable of employing large numbers of unskilled workers, that can raise productivity through innovation, and that can power growth through exports. Such structural transformation is a key driver of growth, and between 1950-1996 about half of the economic catch-up by developing countries (led by East Asia) was due to rising productivity in manufacturing combined with growing agricultural output. Africa, however, has lagged behind.In 2014, the average share of manufacturing in GDP in sub-Saharan Africa hovered around 10 per cent, unchanged from the 1970s, leading some observers to be pessimistic about Africa's potential to catch the wave of sustained rapid growth and rising incomes. Industries Without Smokestacks: Industrialization in Africa Reconsidered challenges this view. It argues that other activities sharing the characteristics of manufacturing- including tourism, ICT, and other services as well as food processing and horticulture- are beginning to play a role analogous to that played by manufacturing in East Asia. This reflects not only changes in the global organization of industries since the early era of rapid East Asian growth, but also advantages unique to Africa. These 'industries without smokestacks' offer new opportunities for Africa to grow in coming decades.
Collins said it will likely be a lengthy process of demolishing the smokestacks. He said it will probably look similar to what Carlsbad, California is currently doing to remove their 400-foot-tall smokestack.
One is Morro Rock, the 23-million-year-old plug of an ancient volcano, rising 576 feet out of the sea. The other is a trident of 450-foot concrete smokestacks, built half a century ago for a seaside power plant.
Coal power plants use tall smokestacks to release air pollutants like sulfur dioxide and nitrogen oxides high into the atmosphere, in an effort to disperse pollution and decrease the impact on the local community. But wind currents are faster at higher altitudes, causing pollution to travel hundreds of miles to other areas or states. While the EPA has been attempting to decrease interstate air pollution, there has been an increase in smokestacks taller than 500 feet in the last four years.
Along with using these technologies, another technique is used which reduces harmful gases over a given area. This technique is to build the stack very high, because wind speeds are greater at high elevations, and the dispersion of the gases results in less gas remaining in a given area. Also, by building stacks higher than inversion layers the gas can be dispersed even more effectively. Some smokestacks are comparable to the largest buildings in the world, such as that in Figure 1, which is about as tall as the Empire State Building. Although dispersion of certain pollutants helps in some cases, this technique does not by any means solve the pollution problem of these power plants since these pollutants may cause problems downwind such as acid rain.[3]
The study shows that winds blowing from Asia toward North America carry emissions from Chinese power plants and other human sources to the surface waters of the North Pacific Ocean. Peak measurements show that early 60 percent of the iron in one vast swath emanates from smokestacks.
San Diego needs a mayor who will bring prosperity,Who will help to build up factories in this city by the sea. Oh, we love to have the tourists come, in our sunshine to bask, But we need some smokestacks: Give us work: a chance is all we ask.
Smokestack designs must be tall enough to release gases and smoke above the local inversion layer. The smoke then rises and blows away rather than settling into the immediate area. Surface inversions occur, usually at night, when cold ground chills the air directly above, and the heavier cold air stays in place. Night inversions may be a few hundred feet thick, so smokestacks must be designed to be taller than the local conditions.
Power plants burning fossil fuels, especially coal, require smokestacks to release the smoke and gases generated during burning. Taller smokestacks reduce the impact of pollutants on the local area by spreading the released pollutants over a larger area.
The Environmental Protection Agency requires that coal-generating power plants have their smokestack emissions checked annually by an independent auditor. Despite this testing, air pollution from power-generating plants causes approximately 52,000 premature deaths in the U.S., according to a 2013 MIT study, with a higher number of deaths occurring in the eastern U.S. where coal has a higher sulfur content. Coal-generated air pollution released through smokestacks historically have had similarly deadly consequences.
In December of 1952, the combined smoke from burning coal released from London's home chimneys and factory smokestacks became especially thick. An unexpected temperature inversion trapped the smoke. The sulfur oxides in the smoke reacted with water vapor in fog to form sulfuric acid droplets. These droplets especially impacted those with existing lung conditions.
The near surface concentrations of smokestack pollutants as well as their deposition are focused mainly along the major shipping lanes, influencing coastal regions in particular, but pollutants released from smokestacks are also transported over longer distances (e.g. Claremar et al. (2017), Jonson et al. (2015)). Pollutant release into the atmosphere generates a variety of risks to human health, primarily to the respiratory organs and the cardiovascular system (Corbett et al., 2007). Additional consequences include the formation of ground-level ozone, and enhanced eutrophication and acidification of water and soil. Particulate matter also absorbs or reflects radiation: the net effect of emissions from the maritime sector on the global radiation balance is estimated to be negative, resulting in a cooling effect on the global climate (Eyring et al., 2005; Fuglestvedt et al., 2009). Pollutant releases from smokestacks undergo transformations in the atmosphere and are deposited at the surface by dry or wet deposition. Transformation and deposition processes are dependent on turbulence, clouds and precipitation; thus the impact of smokestack release is interlinked with local meteorological conditions and atmospheric transport processes.
In 2008 the EU launched the Marine Strategy Framework Directive (MSFD), an ambitious plan for efficient protection of the marine environment (EU, 2008a). The ultimate goal of the MSFD is to reach Good Environmental Status of the marine environment. To define Good Environmental Status, 11 descriptors are used, and for each descriptor a set of measurable indicators are identified. The descriptors of greatest relevance for pollutant release from smokestacks and scrubbers are Contaminants (Descriptor 8) and Eutrophication (Descriptor 5). 2ff7e9595c
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