Municipal waste incineration

A. M. Ujihara and M. Gough, ManagingMsh From Municipal Waste Incinerators, Resources for the Future, Washington, D.C., 1989. 

Hydrogen chloride in the lungs can cause pulmonary edema, a life threatening condition. In order for HCl in air to reach the lungs, it must be transported either as an aerosol or as a deposit on soot particles of less than 3 p.m in diameter. A procedure for the removal of 99% of the HCl from municipal waste incinerators has been developed (87). Lime is employed as a dry adsorbent which is collected in a filter bag system. 

Concentration of WTE Incinerators The total number of municipal waste incinerator facihties as hsted in the Solid Waste Digest, vol. 4, no. 9 September 1994 (a publication of Chartwell Information Publishers of Alexandria, VA) is 62. See Table 25-69, which covers over 200 existing units. The wastes burned in these facilities totals 8.44 percent of total municipal wastes managed in landfills, incinerators, and transfer stations. This amounts to 88,470 tons per day combusted municipal waste. 

Table 10.2 Selected emission limits for municipal waste incineration (units mg/m ) ...

EEC Directive on existing municipal waste incineration plants... 

Selective catalytic reduction (SCR) and selective noncatalytic reduction processes (SNCR) are widely employed in large industrial and utility boiler plants, as well as in municipal waste incineration plants and other combustion processes. They are used to complement mechanical improvements (such as low NOx burners and furnace design modifications) as an aid to reducing the emission levels of NOx, S02, and other noxious gases into the atmosphere. 

The fate of aromatic bromine compounds such as brominated dibenzodioxins occurring on fly ash of municipal waste incinerators has been deduced from appropriate laboratory experiments. Stereoselective, first order ipso-substitution of bromine by chlorine is observed. 

By variation of temperature and air flow rate burning conditions ranging form a smoldering fire to an open fire (e.g. conditions of a municipal waste incinerator) can be modeled. Details can be found in the literature (refs. 8-10). The furnaces are complementary to each other. In general similar results are obtained. 

Fate of Aromatic Bromine Compounds During Municipal Waste Incineration... 

Aromatic bromine compounds can be formed and transformed during various thermal processes, like aromatic chlorine compounds (ref. 22). Brominated dibenzodioxins and -furans and mixed brominated/chlorinated compounds have been detected in trace levels in the fly ash of a municipal waste incinerator (ref. 23).Chlorine is generally abundant compared to the bromine of typical municipal waste the chlorine vs. bromine ratio is in the range of 250 1. 

We have simulated the relevant reactions occurring at 3(X)°C on the surface of fly ash of electrostatic filters of a municipal waste incinerator (MWI) using the following device (Fig. 9) (ref. 24). 

These results show the fate of aromatic bromine compounds during municipal waste incineration bromine is exchanged by chlorine on the surface of fly ash at the electrostatic precipitator at 250-3(X)°C. But the toxic potential at brominated dibenzodioxins and furans is not reduced by these transformations. The increase of PCDD/F concentration in MWI by adding bromine compounds has been pointed out by Lahl and coworkers (ref. 26). 

Mowrer 1,1 Nordin (1987) Characterization of halogenated organic acids in flue gases from municipal waste incinerators. Chemosphere 16 1181-1192. 

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. 

The literature includes a number of mis-matches, the following standing as examples for the many The use of bovine liver and other animal tissues for QC in the analysis of hmnan body fluids should not be considered by analysts. The matrix and the levels of trace elements do not match the levels to be analyzed, which may lead to serious errors. An even more severe mis-use was recently reported by Schuhma-cher et al. (1996) for NIST SRM 1577a Bovine Liver, which was used for QC in the analysis of trace elements in plant materials and soil samples in the vicinity of a municipal waste incinerator. Also recently, Cheung and Wong (1997) described how the quality control for the analysis of trace elements in clams (shellfish) and sediments was performed with the same material NIST SRM 1646, Estuarine sediment. Whilst the selected SRM was appropriate for sediments, its usefulness as a QC tool for clams is difficult to prove see also Chapter 8. This inappropriate use is the more mystifying because a broad selection of suitable shellfish RMs from various producers is available. 

Chlorinated compounds PCP, PCBs, PCDD/Fs Manufacture of pesticide and herbicide (D) Wood preservation sites (P) Pulp and paper production (P) Municipal waste incineration (P,D) Plastics, fire-retardants manufacture (P,D) Chlorinated phenols -3.6 Chlorinated hydrocarbons - 2.4 [43, 44]... 

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

Both pathways have been shown to be relevant for PCDD/F formation in municipal-waste incinerations. Chlorophenols can be converted to PCDD by copper species known in synthetic chemistry as the Ullmann type II coupling reaction. By use of isotope labeling techniques in competitive concurrent reactions with both reactions performed in laboratory experiments it was shown that precursor theory pathways from chlorophenols may be more important compared to the de novo pathway, but either competing pathway strongly depends on such conditions as temperature, air flow rate, and residence time. It may be difficult to model the complex reahty of large incinerators using relevant laboratory experiments. 

Tong, H.Y. Monson, S.J. Gross, M.L. Huang, L.Q. Monohromopolychlorodi-henzo-p-Dioxins and Dihenzoihrans in Municipal Waste Incinerator Fly Ash. Anal. Chem. 1991,63,2697-2705. 

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). 

The flue gas from municipal waste incinerator boilers contains SO2, and HCl. To remove these harmful components simultaneously by dry process, electron beam treatment method was investigated. The pilot-scale test was conducted in Matsudo, Japan, in 1992 with a flue gas of 1000 m /hr [34]. Recently, dioxins, namely, poly-chlorinated-di-benzo-paradioxins (PCDDs) and poly-chrorinated-di-benzo-furan (PCDFs), from incinerators have become a very serious problem because of their high toxicity. Pilot-scale tests to decompose dioxins by electron beam irradiation were conducted in Karlsruhe, Germany [35], and in Takahama, Japan [36], using almost the same capacity of flue gas, 1000 m /hr. Very promising results were obtained with decomposing more than 90% of dioxins. 

Lancellotti, I. Manfredini, T. 2001. The possibility to recycle solid residues of the municipal waste incineration into a ceramic tile body. Journal of Material Science, 36, 4869-4873. 

Falcone, R., Hreglich, S., Profilo, B. Vallotto, M. 2003. Inertization by vitrification of mixtures of municipal waste incineration slag and ash and valorisation of the obtained glass products. Rivista della Stazione Sperimentale del Vetro, 4, 25-29. 

Also M. Gough and D. Turnbull, Use of a Threshold Model for the Estimation of Risk Associated with Exposure to Chlorinated Dibenzo-p-di-oxins and Dibenzofurans, in H. A. Hattemer-Frey and . C. Travis, eds., Health Effects of Municipal Waste Incineration (Boca Raton, Fla. CRS Press, 1989), pp.20151-46. 

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