Emissions from combustion sources

Sidhu S, Gullet B, Striebich R, Klosterman JR, Contreras J, DeVito M (2005) Endocrine disrupting chemical emissions from combustion sources diesel particulate emissions and domestic waste open bum emissions. Atmos Environ 39 801-811... 

Tucker WG. 1987. Characterization of emissions from combustion sources Controlled studies. Atmos Environ 21(2) 281-284. 

The different size modes reflect differences in particle sources, transformations, and sinks (Finlayson-Pitts and Pitts 2000). For example, coarse particles are generated by mechanical processes such as wind erosion of soil, wave action in the oceans, and abrasion of plant material. In contrast, many of the fine particles in the atmosphere are produced from either primary emissions from combustion sources or via atmospheric gas-to-particle conversions (i.e., new particle formation). The relative and absolute sizes of particle modes, as well as the number of modes, can vary greatly in different locations and at different times. In addition, the chemical composition of particles within one size... 

Matthews TG, Reed TJ, Tromberg BJ, et al. 1985. Formaldehyde emission from combustion sources and solid formaldehyde-resin-containing products Potential impact on indoor formaldehyde concentrations. In Gammage RB, Kaye SV, Jacobs VA, ed. Indoor air and human health. Chelsea, MI Lewis Publishers, Inc., 131-150. 

It is now known that endocrine disrupting chemicals are emitted from combustion sources. Interest has focused on the emissions of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/F), which are also known carcinogens. However, oxy-PAH, epoxides, and other oxygenated species are known EDCs. These can also be emitted from combustion sources, although they are not well characterized. They are semipolar compounds that are difficult to analyze. Thus, improved methods of analysis are needed in conjunction with biological testing to determine the nature and quantity of EDC emissions from combustion sources. 

Concern about dioxin s effect on human health can be traced to a number of Industrial exposures. Its recognition as a byproduct In the production of large-scale quantities of chlorophenols such as 2,4,5- trichlorophenol (TCP) and pentachlorophenol (PCP), the finding of birth defects In animals exposed to 2,3,7,8- TCDD, and the recognition In the 1970 s of a more general environmental contamination due to emissions from combustion sources. 

Sources From Combustion Processes. In 1977, PCDD and PCDF were detected in particulate emissions from municipal incinerators (5). Similar data were soon reported from around the world. In 1980, workers at Dow Chemical Company, using the most sensitive and specific analytical techniques of that time, detected a range of PCDD in residues from many combustion processes (6). These workers postulated that all combustion processes that contain chlorine sources produce PCDD. Although this postulate is not supported in all situations, dioxin emissions from combustion sources are major contributors to PCDD in the environment (7). 

Assessment of ODD and CDF emissions from combustion sources has received limited study. Previous work included studies of emissions from hazardous waste incinerators, utility boilers, and municipal waste combustion. Even for those source categories that had previously been tested, there is considerable variation in the extent and quality of testing and the test methods employed. 

Future Work. Although the majority of the planned Tier 4 study has been completed, there are a number of continuing efforts that EPA plans to pursue with respect to CDD emissions from combustion sources. These include the following ... 

Environmental considerations also were reflected in coal production and consumption statistics, including regional production patterns and economic sector utilization characteristics. Average coal sulfur content, as produced, declined from 2.3% in 1973 to 1.6% in 1980 and 1.3% in 1990. Coal ash content declined similarly, from 13.1% in 1973 to 11.1% in 1980 and 9.9% in 1990. These numbers clearly reflect a trend toward utilization of coal that produces less SO2 and less flyash to capture. Emissions from coal in the 1990s were 14 x 10 t /yr of SO2 and 450 x 10 t /yr of particulates generated by coal combustion at electric utiUties. The total coal combustion emissions from all sources were only slightly higher than the emissions from electric utiUty coal utilization (6). 

The emissions from combustion processes may be predicted to some extent if the variables of the processes are completely defined. Figure 6-7 indicates how the emissions from a combustion source would be expected to vary with the temperature of the reaction. No absolute values are shown, as these will vary greatly with fuel type, independent variables of the combustion process, etc. 

Improved furnace designs and combustion techniques could reduce NOx emissions from stationary sources by 40-70%. These methods are not in widespread use now. The processes for removing NOx from flue gases are in an early stage of development. 

Use of bromine-containing additives (ethylene dibromide) in leaded gasoline results in the release of bromomethane in exhaust fumes (about 70-220 pg/m of exhaust) (Harsch and Rasmussen 1977), and this may have been significant source of bromomethane release in the past. Combustion of unleaded gasoline releases much less bromomethane (about 4-5 pg/m ), so current emissions from this source are presumably much lower than previously, and are likely to decrease further as leaded gasoline continues to be phased out. 

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. 

In addition to emissions from combustion processes, other potential sources of airborne compounds from... 

HCB was neither imported nor manufactured in South Korea. Domestic emission, therefore, should originate from process such as combustion of organic matters combined with chlorine and from impurities in the production of chemicals and pesticides. HCB emission for 2000 in South Korea was estimated in a preliminary study of emission inventory using top-down approach (KMOE, 2003b). Emissions from some sources in 2005 were determined by measuring concentrations in archived samples originally collected for analysis of PCDDs/DFs in 2001-2003 (KMOE, 2005a). 

Although the production of CDDs during combustion processes are highlighted here, most samples from combustion sources show a complex mixture of isomers and congeners of CDDs and CDFs which vary in their relative concentrations (Kolenda et al. 1994 Nestrick and Lamparski 1983 Vikelsoe et al. 1994). CDDs have been detected in emissions (flue gas and fly ash) from municipal, hazardous waste, and industrial incinerators (Buser 1987 Oppelt 1991 Sedman and Esparza 1991 Schecter 1983). 

A number of combustion and chemical production processes contribute to environmental concentrations of PCDD/F. Sources that have traditionally caused the greatest concern include municipal waste incinerators, hospital waste incinerators, bleached chemical wood pulp and paper mills, motor vehicles and wood combustion. We have attempted to represent the most recent data available on PCDD/F emissions from these sources. It should be remembered that the list presented here is by no means exhaustive. Potential sources of TCDD not discussed in the following paragraphs include discharges from metal processing and treatment plants, copper smelting plants and pentachlorophenol production. 

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