Emissions from municipal incinerators

Scheidl K, Kuna RP, Wurst F. 1985. Chlorinated dioxins and furans in emissions from municipal incineration. Chemosphere 14 913-917. 

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). 

EPA has a project underway to respond to the requirements of Section 102 of the Hazardous and Solid Waste Act of 1984 (HSWA) concerning CDD emissions from municipal incinerators. This effort is intended to identify design and operating guidelines to minimize CDD emissions. 

Release of trichloroethylene also occurs at treatment and disposal sites. Water treatment facilities may release trichloroethylene from contaminated water through volatilization and air-stripping procedures (EPA 1985e). Trichloroethylene is also released to the atmosphere through gaseous emissions from landfills. The compound may occur as either an original contaminant or as a result of the decomposition of tetrachloroethylene. Trichloroethylene has also been detected in stack emissions from the incineration of municipal and hazardous waste (James et al. 1985 Oppelt 1987). 

Low levels of cresols are constantly emitted to the atmosphere in the exhaust from motor vehicle engines using petroleum based-fuels (Hampton et al. 1982 Johnson et al. 1989 Seizinger and Dimitriades 1972). Cresols have been identified in stack emissions from municipal waste incinerators (James et al. 1984 Junk and Ford 1980) and in emissions from the incineration of vegetable materials (Liberti et al. 1983). Cresols have also been identified as a component of fly ash from coal combustion (Junk and Ford 1980). Therefore, coal- and petroleum-fueled electricity-generating facilities are likely to emit cresols to the air. The combustion of wood (Hawthorne et al. 1988, 1989) and cigarettes (Arrendale et al. 1982 Novotny et al. 1982) also emits cresols to the ambient air. Cresols are also formed in the atmosphere as a result of reactions between toluene and photochemically generated hydroxy radicals (Leone et al. 1985). 

CDDs are released into the air in emissions from municipal solid waste and industrial incinerators. Exhaust from vehicles powered with leaded and unleaded gasoline and diesel fuel also release CDDs to the air. Other sources of CDDs in air include emissions from oil- or coal-fired power plants, burning of chlorinated compounds such as PCBs, and cigarette smoke. CDDs formed during combustion processes are associated with small particles in the air, such as ash. The larger particles will be deposited close to the emission source, while very small particles may be... 

Beychok MR. 1987. A data base of dioxin and furan emissions from municipal refuse incinerators. Atmos Environ 21 29-36. 

Hirota, K. Hakoda, T. Taguchi, M. Takigami, M. Kim, H. Kojima, T. Application of Electron Beam for the Reduction of PCDD/F Emission from Municipal Solid Waste Incinerators, Environ. Sci. Technol. 2003, 37, 3164-3170. 

PCNs have also been found in incinerator and metal refining emissions, as contaminants in PCB formulations [68,69] and have also been detected in air [65,66,70]. Other sources of PCNs to the atmosphere include chlor-aUcali processes and thermal processes [71], particularly emissions from municipal solid waste incinerators (MSWl) [72]. In developing countries, sources of PCNs are likely to be incinerators. Jaward et al. [70] measured significant levels of PCNs in air off the coast of West Africa and South Africa, indicating that this class of compounds cannot be neglected in developing countries. It also indicates that... 

Mercury is one of a number of toxic heavy metals that occur in trace amounts in fossil fuels, particularly coal, and are also present in waste materials. During the combustion of fuels or wastes in power plants and utility boilers, these metals can be released to the atmosphere unless remedial action is taken. Emissions from municipal waste incinerators can substantially add to the environmental audit of heavy metals, since domestic and industrial waste often contains many sources of heavy metals. Mercury vapor is particularly difficult to capture from combustion gas streams due to its volatility. Some processes under study for the removal of mercury from flue gas streams are based upon the injection of finely ground activated carbon. The efficiency of mercury sorption depends upon the mercury speciation and the gas temperature. The capture of elemental mercury can be enhanced by impregnating the activated carbon with sulfur, with the formation of less volatile mercuric sulfide [37] this technique has been applied to the removal of mercury from natural gas streams. One of the principal difficulties in removing Hg from flue gas streams is that the extent of adsorption is very low at the temperatures typically encountered, and it is often impractical to consider cooling these large volumes of gas. 

Respirable particulate or gaseous forms of lead may be inhaled. Sources include cigarette smoke vehicle exhaust emissions from municipal waste incinerators, iron and steel plants, smelting and refining operations, lead acid battery manufacturing facilities, and sandblasting and burning of surfaces coated with lead paint. Particulate air emissions may eventually deposit and contaminate the soil. 

This fraction can lead to emissions of cadmium to the environment (atmospheric and water emissions). Today, in the EU members states these emissions need to be strictly controlled according to EU Directives on Waste (91/156/EEC), on Emissions from Municipal Solid Waste Incinerators (2000/76/EC), and from Landfills (99/31/EC). These emissions could be further reduced by an optimised collection efficiency of portable rechargeable batteries. 

EXPOSURE ROUTES Inhalation (automobile exhaust, smoking, emissions from municipal waste incinerators, chemical industries and metal manufacturing industries) ingestion (wastewater facilities, groundwater near landfills) absorption occupational exposure. 

The following paragraphs are based on typical information for incinerator flue gases [29.7] and on the use of a standard conunercial hydrated lime, with more than 94 % Ca(OH)2, a BET surface area of at least 12 m /g and a median particle size of less than 8 pm. Table 29.1 gives typical concentrations of HCl, HF and SO2 in the untreated gases from municipal incinerators and an indicative range of emission limits (which vary from one country to another and with the type of installation). 

Carbon-based processes (both direct injection and fixed-bed) have been developed for control of mercury emission from municipal- and hazardous-waste incinerators [10, llj. Existing data from the incinerators provide some insight on mercury control, but these data cannot be used directly for coal-fired utilities because mercury concentrations, species, and process conditions differ greatly [Ij. For example, municipal solid waste (MSW) mercury concentrations (200 to 1000 pg/m ) are one to two orders of magnitude larger than for flue gases generated by coal combustion sources. 

Venmri scrubbers have been applied to control PM emissions from utility, industrial, commercial, and institutional boilers fired with coal, oil, wood, and liquid waste. They have also been applied to control emission sources in the chemical, mineral products, wood, pulp and paper, rock products, and asphalt manufacrnring industries lead, aluminum, iron and steel, and gray iron production industries and to municipal solid waste incinerators. Typically, venturi scrubbers are applied where it is necessary to obtain high collection efficiencies for fine PM. Thus, they are applicable to controlling emission sources with high concentrations of submicron PM. 

The pyrolysis of vinylidene chloride produced a range of chlorinated aromatic compounds including polychlorinated benzenes, styrenes, and naphthalenes (Yasahura and Morita 1988), and a series of chlorinated acids including chlorobenzoic acids has been identified in emissions from a municipal incinerator (Mowrer and Nordin 1987). 

Reductions in U.S. mercuiy emissions from medical and municipal waste incinerators and other industrial sectors have already occurred. Additional emission reductions from some coal-fired power plants have also already begun as co-benefits from technologies used to control SO2 and NO emissions. These mercury emissions from power plants are, however, expected to be reduced further over the next few decades. Meanwhile, changes in mercuiy emissions in other parts of the world may also affect some U.S. ecosystems. 

Greim H. 1990. Toxicological evaluation of emission from modem municipal waste incinerators. 

Trichlorophenol may enter the environment as emissions from combustion of fossil fuels and incineration of municipal wastes, as well as emissions from its manufacture and use as a pesticide, and in the use of 2,4-D, in which it is an impurity. Significant amounts may result from the chlorination of phenol-containing waters (United States National Library of Medicine, 1997). 

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