Nitrogen dioxide emissions

Jenkin ME (2004) Analysis of sources and partitioning of oxidant in the UK—Part 2 contributions of nitrogen dioxide emissions and background ozone at a kerbside location in London. Atmos Environ 38(30) 5131—5138... 

A new system to reduce sulfur dioxide and nitrogen dioxide emissions... 

Local regulations require that the emissions of sulfur dioxide be less than 200 ppm (by moles) from your plant. They also require you to reduce nitrogen dioxide emissions to less than 50 ppm. You decide that the most economical method for control of these for your plant is to utilize ammonia-based processes. The proposed system is as follows ... 

Alien substances in air, as far as they are found in large quantities in locally limited areas, are usually the consequence of human activities. In densely populated areas, a constant rise in nitrogen dioxide emissions over... 

J. Lanier and co-workers, "Sulfur Dioxide and Nitrogen Oxide Emissions Control in a Coal-Eked MHD System," ASME Winter Annual Meeting Adanta, Ga., Dec. 1979. 

Air Pollution. Particulates and sulfur dioxide emissions from commercial oil shale operations would require proper control technology. Compliance monitoring carried out at the Unocal Parachute Creek Project for respirable particulates, oxides of nitrogen, and sulfur dioxide from 1986 to 1990 indicate a +99% reduction in sulfur emissions at the retort and shale oil upgrading faciUties. No violations for unauthorized air emissions were issued by the U.S. Environmental Protection Agency during this time (62). 

In 1990, a test using scrap tires (2x2 in. I DE) to generate steam for electricity was conducted at the Elexsys plant. The I DE replaced 20% of the plant s coal. Results showed that IDE is an environmentally sound fuel. Particulate emissions were reduced by the lower ash content of IDE, volatile organic compounds (VOC) were reduced because of more efficient burning of I DE compared to coal, and carbon dioxide emissions were reduced because I DE contains half the fixed carbon found in coal. Nitrogen oxide, chlorine emissions, and metals were also reduced, and ferrous metals and dioxins were nondetectable (7). 

Plant nutrient sulfur has been growing in importance worldwide as food production trends increase while overall incidental sulfur inputs diminish. Increasing crop production, reduced sulfur dioxide emissions, and shifts in fertilizer sources have led to a global increase of crop nutritional sulfur deficiencies. Despite the vital role of sulfur in crop nutrition, most of the growth in world fertilizer consumption has been in sulfiir-free nitrogen and phosphoms fertilizers (see Fertilizers). 

Acid deposition occurs when sulfur dioxide and nitrogen oxide emissions are transformed in the atmosphere and return to the earth in rain, fog or snow. Approximately 20 million tons of SOj are emitted annually in the United States, mostly from the burning of fossil fuels by electric utilities. Acid rain damages lakes, harms forests and buildings, contributes to reduced visibility, and is suspected of damaging health. 

Here a ehemieal reaetion produees a moleeule with eleetrons in an exeited state. Upon deeay to the ground state the liberated radiation is deteeted. One sueh example is the reaetion between ozone and nitrie oxide to form nitrogen dioxide emitting radiation in the near infra-red in the 0.5-3/x region. The teehnique finds use for measuring nitrie oxide in ambient air or staek emissions. 

SIPs are intended to prevent air pollution emergency episodes. The phms are directed toward preventing excessive buildup of air pollutants tliat me known to be harmful to the population and the enviroiunent when concentrations exceed certain limits. The compounds affected under the implementation plans are sulfur dioxide, particulate matter, ctirbon monoxide, nitrogen dioxide, and ozone. A contingency plan, which will outline the steps to be taken in tlie event tliat a particular pollutant concentration reaches tlie level at wliich it can be considered to be hannful, must be included in each implementation plan. The implementation plans are solely based on tlie continuous emission of tlie previously stated air pollutants. They do not mandate any actions to be taken in tlie event of an accidental toxic release. 

In contrast to carbon monoxide, small hydrocarbon molecules and soot that result from incomplete conversion of the hydrocarbon fuels, nitric oxide and nitrogen dioxide, are noxious emissions that result from the oxidizer—air. However, fuel components that contain nitrogen may also contribute, in a lesser way, to the formation of the oxides of nitrogen. 

Transportation is also the emissions leader. About 75 percent of carbon dioxide emissions and 45 percent of nitrogen oxide emissions come from the transportation sector. If rising levels of CO, are found to be responsible for global warming, and measures are put in place to severely curtail CO, emissions, the measures will have the greatest impact on the transportation sector. 

U.S. Department of Energy, Clean Coal Technology Topical Reports. (1999). Technologies for the Combined Control of Sulfur Dioxide and Nitrogen Oxides Emissions from Coal-Fired Boilers. Report No. 13 (May). Washington, DC U.S. Government Printing Office. 

Transportation accounts for about one-fourth of the primary energy consumption in the United States. And unlike other sectors of the economy that can easily switch to cleaner natural gas or electricity, automobiles, trucks, nonroad vehicles, and buses are powered by internal-combustion engines burning petroleum products that produce carbon dioxide, carbon monoxide, nitrogen oxides, and hydrocarbons. Efforts are under way to accelerate the introduction of electric, fuel-cell, and hybrid (electric and fuel) vehicles to replace sonic of these vehicles in both the retail marketplace and in commercial, government, public transit, and private fleets. These vehicles dramatically reduce harmful pollutants and reduce carbon dioxide emissions by as much as 50 percent or more compared to gasoline-powered vehicles. 

Land/atmospheric interfacial processes which impact climate and biological activity on earth are illustrated in Figure 3. Emissions of carbon dioxide, methane, nitrogen dioxide, and chlorofluorocarbons (CFCs) have been linked to the transmission of solar radiation to the surface of the earth as well as to the transmission of terrestrial radiation to space. Should solar radiation be an internal process or an external driver of the hydrologic cycle, weather, and air surface temperatures Compounds of sulfur and nitrogen are associated with acidic precipitation and damage to vegetation, aquatic life, and physical structures. 

While natural emissions of sulphur and nitrogen exist, over 95% of the sulphur emissions in eastern North America are of man-made origin. Natural sources of nitrogen are less well estabUshed but are estimated to be small when compared to the man-made emissions 21). The distribution of North American sources of sulphur dioxide and nitrogen oxides are shown in Figure 2. In 1980, which has served as the base period for the assessment of emissions,it was estimated that sulphur dioxide emissions were Canada - 4.8 million tonnes (metric) and the United States - 24 million tonnes nitrogen oxides emissions were Canada - 1.8 million tonnes and the United States - 20 million tonnes. The more recent trends for sulphur dioxide emissions in Canada and the emission control limits are shown in Figure 3 14). 

Nitrogen Dioxide (NO2) Is a major pollutant originating from natural and man-made sources. It has been estimated that a total of about 150 million tons of NOx are emitted to the atmosphere each year, of which about 50% results from man-made sources (21). In urban areas, man-made emissions dominate, producing elevated ambient levels. Worldwide, fossil-fuel combustion accounts for about 75% of man-made NOx emissions, which Is divided equally between stationary sources, such as power plants, and mobile sources. These high temperature combustion processes emit the primary pollutant nitric oxide (NO), which Is subsequently transformed to the secondary pollutant NO2 through photochemical oxidation. 

Based solely on this relationship, it has been predicted that the ozone concentration should be about 2 pphm at solar noon in the United States. Indeed [7], in unpolluted environments, ozone concentrations are usually in the range of 2-5 pphm. However, in polluted urban areas, ozone concentrations can be as high as 50 pphm. Peroxy radicals formed from hydrocarbon emissions cause this enhanced ozone concentration. These radicals oxidize nitric oxide to nitrogen dioxide, thereby shifting the above steady-state relationship to higher ozone levels. 

The environmental problem of sulfur dioxide emission, as has been pointed out, is very much associated with sulfidic sources of metals, among which a peer example is copper production. In this context, it would be beneficial to describe the past and present approaches to copper smelting. In the past, copper metallurgy was dominated by reverberatory furnaces for smelting sulfidic copper concentrate to matte, followed by the use of Pierce-Smith converters to convert the matte into blister copper. The sulfur dioxide stream from the reverberatory furnaces is continuous but not rich in sulfur dioxide (about 1%) because it contains carbon dioxide and water vapor (products of fuel combustion), nitrogen from the air (used in the combustion of that fuel), and excess air. The gas is quite dilute and unworthy of economical conversion of its sulfur content into sulfuric acid. In the past, the course chosen was to construct stacks to disperse the gas into the atmosphere in order to minimize its adverse effects on the immediate surroundings. However, this is not an en-... 

In addition to the energy savings, the new process also has substantial environmental benefits. Along with the elimination of lead and nickel gases, carbon dioxide, carbon monoxide, and nitrogen oxide emissions from combustion will decrease. The consumption of refractory (a heat-resisting... 

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