Nitrogen oxide emission control

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. 

An important consequence is that control of atmospheric organic aerosol concentrations can be achieved by two types of control strategies specific control of precursors with high afa may prove to be as efficient as total hydrocarbon and nitrogen oxides emission control. 

Nitrogen oxide emission control M G V205-W0/fi02 300-400 1 4-10,000 GHSV [16] 306... 

Postformation nitrogen oxide emission control measures include selective catalytic and noncatalytic reduction with ammonia, which between them are used by some 900 power station installations worldwide [51]. The catalytic removal methods are 70-90% efficient at NOx removal, but are more expensive to operate than the noncatalytic methods which are 30-80% efficient. Ammonia or methane noncatalytic reduction of NOx to elemental nitrogen is also an effective method which is cost-effective for high concentration sources such as nitric acid plants (Chap. 11). NOx capture in packed beds is less expensive, but this method is not particularly effective [23]. It is also not a very practical method either for utilities or for transportation sources. Two-stage scrubbing has also been proposed as an effective end-of-pipe NOx control measure. The first stage uses water alone and the second uses aqueous urea. 

Srivastava, R.K., Hall, R.E., Khan, S., Culligan, K., and Lani, B.W. 2005. Nitrogen oxides emission control options for coal-fired electric utility boilers. Journal of the Air Waste Management Association, 55 1367-1388. 

Title rV Acid Deposition Control - As we all know, acid rain 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... 

New low-NO, burners are effective in reducing emissions from both new power plants and existing plants that are being retrofitted. Low NO, burners limit the formation of nitrogen oxides by controlling the mixing of fuel and air, in effect... 

Ammonia Plants - New ammonia plants should set as a target the achievement of nitrogen oxide emissions of not more than 0.5 kg/t of product (expressed as NOj at 3%). Ammonia releases in liquid effluents can be controlled to 0.1 kg/t of product. Condensates from ammonia produetion should be reused. 

U.S. Department of Energy, Clean Coal Technology Topical Reports. (1999). Reburmng Technologies for the Control of Nitrogen Oxides Emissions from Coal-Fired Boilers. Report No. 14 (May). Washington, DC U.S. 

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). 

Less, but still significant, information is available on the surface chemistry of other nitrogen oxides. In terms of N20, that molecule has been shown to be quite reactive on most metals on Rh(110), for instance, it decomposes between 60 and 190 K, and results in N2 desorption [18]. N02 is also fairly reactive, but tends to convert into a mixed layer of adsorbed NO and atomic oxygen [19] on Pd(lll), this happens at 180 K, and is partially inhibited at high coverages. Ultimately, though the chemistry of the catalytic reduction of nitrogen oxide emissions is in most cases controlled by the conversion of NO. 

FCC feed, sulfur compounds in, 11 716 FCC unit emissions, 11 714 controlling, 11 689-694 FCC unit regenerators, 11 713 air distribution systems in, 11 726 catalyst emissions from, 11 714—715 CO2 emissions from, 11 720—721 configuration and mechanical hardware in, 11 722-731 cyclones in, 11 726-728 design of, 11 722-723 flue gas handling in, 11 729 fluidization in, 11 723-725 nitrogen oxide emissions from,... 

Kemal, A., J. Dorn, and C. T. Bowman. 1997. Control of nitrogen oxide emissions from air-breathing combustors using partial premixing of fuel and air. Western States Section of the Combustion Institute. Paper No. 97F-136. 

C.T. Bowman. Control of Combustion-Generated Nitrogen Oxide Emissions Technology Driven by Regulation. Proc. Combust. Inst., 24 859-878,1992. 

While the development of flue gas clean-up processes has been progressing for many years, a satisfactory process is not yet available. Lime/limestone wet flue gas desulfurization (FGD) scrubber is the most widely used process in the utility industry at present, owing to the fact that it is the most technically developed and generally the most economically attractive. In spite of this, it is expensive and accounts for about 25-35% of the capital and operating costs of a power plant. Techniques for the post combustion control of nitrogen oxides emissions have not been developed as extensively as those for control of sulfur dioxide emissions. Several approaches have been proposed. Among these, ammonia-based selective catalytic reduction (SCR) has received the most attention. But, SCR may not be suitable for U.S. coal-fired power plants because of reliability concerns and other unresolved technical issues (1). These include uncertain catalyst life, water disposal requirements, and the effects of ammonia by-products on plant components downstream from the reactor. The sensitivity of SCR processes to the cost of NH3 is also the subject of some concern. 

In general, the greatest resolution can be obtained in estimates of current or recent historical (within the last 10 to 15 years) emissions. This is because reliable data on fuel use (both quality and quantity) and other activity levels are available, and good estimates of emission coefficients and control efficiencies are available. As one goes further back in time, the data needed for detailed emission estimates are either not available or are less reliable. Recently, SOp and nitrogen oxide emissions were estimated for EPA for the period 1900 to 1980 at the state level by fuel and source sector (4J1). It was particularly difficult to obtain reliable estimates of pre-1940 fuel use and quality, control efficiency, and emission coefficients. Obviously, the less data that are available, the simpler the methodology that must be used. A discussion of a data set required for detailed analysis of emissions and deposition is beyond the scope of this paper, but is available elsewhere (6). 

For the control of carbon monoxide, hydrocarbon, and nitrogen oxide emissions from automobiles, oval-shaped extruded cordierite or metal monolith catalysts are wrapped in ceramic wool and placed inside a stainless steel casing (Fig. 19-18a). The catalytic metals are Pt-Rh or Pd-Rh, or combinations. Cell sizes typically ranges between 400 and 600 cells per square inch. The catalysts achieve over 90 percent reduction in all three pollutants. 

Selective catalytic reduction (SCR) catalysts are used for controlling nitrogen oxide emissions from power plants. The reducing agent is... 

Control Techniques for Nitrogen Oxide Emissions from Stationary Sources, ... 

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