Emissions control from stationary

The East Bridgewater facility (also serving Brockton), was built with an incinerator, (conventional except that it has bag filters for emission control), and as an alternate disposal means, a Resource Recovery facility. In 1972 CEA entered into an agreement with Arthur D. Little (ADL) to develop processes for emission controls from stationary sources and also for treatment of Municipal Solid Wastes. 

Emission control from heavy duty diesel engines in vehicles and stationary sources involves the use of ammonium to selectively reduce N O, from the exhaust gas. This NO removal system is called selective catalytic reduction by ammonium (NH3-SGR) and it is additionally used for the catalytic oxidation of GO and HGs.The ammonia primarily reacts in the SGR catalytic converter with NO2 to form nitrogen and water. Excess ammonia is converted to nitrogen and water on reaction with residual oxygen. As ammonia is a toxic substance, the actual reducing agent used in motor vehicle applications is urea. Urea is manufactured commercially and is both ground water compatible and chemically stable under ambient conditions [46]. 

As Table I indicates, almost half of the total national NOa emissions result from stationary fuel combustion. In principle, NOa emissions from fossil fuel-combustion systems can be reduced by three methods fuel cleaning (removal of the fuel nitrogen), combustion modification, and flue gas treatment. Combustion modification appears to be by far the easiest and most economical of the three. Therefore, EPA has assigned to the Control Systems Divisions, Combustion Research Section (CRS) the responsibility for assisting industry in developing technology to re-... 

This covers all NOx emissions both from stationary and mobile sources. The signatory countries are also required to use the best available technology to control emissions from both... 

PGM catalyst technology can also be appHed to the control of emissions from stationary internal combustion engines and gas turbines. Catalysts have been designed to treat carbon monoxide, unbumed hydrocarbons, and nitrogen oxides in the exhaust, which arise as a result of incomplete combustion. To reduce or prevent the formation of NO in the first place, catalytic combustion technology based on platinum or palladium has been developed, which is particularly suitable for appHcation in gas turbines. Environmental legislation enacted in many parts of the world has promoted, and is expected to continue to promote, the use of PGMs in these appHcations. 

Control of stationary sources of air pollution requires the application of either the control concepts mentioned in Chapter 28 of the control devices mentioned in Chapter 29. In some cases, more than one system or device must be used to achieve satisfactory control. The three general methods of control are (1) process change to a less polluting process or to a lowered emission from the existing process through modification of the operation,... 

EPA, 1982. U.S. EPA, Office of Air Quality Planning and Standards, "Control Techniques for Particulate Emissions from Stationary Sources, Volume 1," EPA-450/3-81-005a, Research Triangle Park, NC, September, 1982. 

Control Technologies for Sulfur Oxide Emission from Stationary Sources," 2" Edition, Research Triangle Park, NC, April, 1981. 

The control of NO from stationary sources includes techniques of modification of the combustion stage (primary measures) and treatment of the effluent gases (secondary measures). The use oflow-temperature NO,.burners, over fire air (OFA), fiue gas recirculation, fuel reburning, staged combustion and water or steam injection are examples of primary measures they are preliminarily attempted, extensively applied and guarantee NO reduction levels of the order of 50% and more. However, they typically do not fit the most stringent emission standards so that secondary measures or flue gas treatment methods must also be applied. 

Although the standard urea-ammonia SCR technology is nowadays well established and used world-wide for the control of NO, from stationary sources, additional applications are predicted in large gas turbines, incinerators, stationary diesel engines and the cement and glass industries in view of the enforcement of stricter emission limits and of the high cost of alternative very efficient primary methods. 

Control of sulfur dioxide emissions from stationary sources (such as power plants) usually takes one of three forms fuel cleaning, also known as fuel beneficiation removal of sulfur during combustion or flue gas processing. 

Reduction of Nitric Oxide with Ammonia. - Control of the emission of NO from stationary sources is possible by selective catalytic reduction, for which up to now NH3 is the only effective reductant in the presence of excess 02. Beside noble metal catalysts Bauerle etal.101 109 and Wu and Nobe108 studied Al2 03-supported vanadium oxide and found this to be highly effective in NO removal which is considerably enhanced by the presence of 02. Alkali metal compounds which are usually added as promoters for S02 oxidation completely inactivate the catalysts for NO reduction. Adsorption kinetic studies indicated first-order dependence on NH3 adsorption. Similar results were obtained for NO on reduced vanadium oxide, but its adsorption on... 

Numerous technologies are available to control NOx emissions from stationary point sources as illustrated in Table 4.1157. 

Hexane. Control of hexane emissions is a major issue and will continue to be so for several years. In the United States, hexane is classified as an air toxic compound. Air toxic compounds are, for the purposes of this article, a list of potentially toxic compounds emitted primarily to the atmosphere in quantities of 909 Kg per year or greater, from stationary (industrial) emission sources. As a result, total hexane emissions for all extraction plants will need to meet the same standards as the best 12% in the industry are now achieving. As a minimum, this will require a well-run mineral oil absorber and excellent control of other loss points throughout the system. 

The American 1970 Clean Air Act defined ambient air quality standards (NAAQS) in the United States for atmospheric ozone, NO, lead, carbon monoxide, sulfur oxides, and PM-10 (particulate matter less than 10 p.m). The strategy to reduce levels of lead, NOx, PM-10, and to some extent carbon monoxide was to control emissions from automobiles that included the phasing-out of leaded fuel. As previously noted, ozone is a product of the photochemical reaction of volatile organic compounds with NOx (photochemical smog), so the balance between organic compounds and NOx pollutants is important in meeting target ozone levels (e.g., 0.12 ppm). Emissions from stationary sources is an important factor, and limits have been set for them. Because of low pressure drop requirements, coated monolithic catalysts... 

Stationary sources are the major contributors of most environmentally important metals in air. Flinn and Reimers (23) reported the annual airborne emissions of metals in the United States from stationary sources projected through 1983 based on production estimates and assuming no changes in processes or control technology. Their results, summarized in Table V, show projected increases in emissions from all environmentally important metals where data are available. Comparatively low concentrations (150-900 ton/year) of the highly toxic metals— berylhum, selenium, and mercury— were reported for the 1969-1971 period. Metals emitted in the highest concentrations are zinc (151,000 ton/year) and titanium (88,000 ton/year), although iron could be expected to exceed these levels. 

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

Alternative Control Techniques Document - NOx Emissions from Stationary Gas Turbines, United States Environmental Protection Agency, EPA-453/R-93-007, 1993. 

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