Sewage sludge combustion

Sohr, W.H., Ott, R., Albertson, O.E. Fluid and Sewage Sludge Combustion, Water Works and Waste Engineering, Sept. 1965, p. 90. 

J. Werther and T. Ogada, Sewage Sludge Combustion, Progr. Energy Combust. Sci. 25(1), 55-116 (1999). 

Fuel Replacement in Sewage Sludge Combustion by Utilization of Chlorinated Hydrocarbon Side Products [158]-[161]... 

F/uidi ed-BedIncinerator. Fluidized-bed incinerators are employed in the paper and petroleum (qv) industries, in the processing of nuclear wastes, and the disposal of sewage sludge. These are quite versatile and can be used for disposal of soflds, Hquids, and gaseous combustible wastes. 

Small amounts of cadmium enter the environment from the natural weathering of minerals, but most is released as a result of human activities such as mining, smelting, fuel combustion, disposal of metal-containing products, and application of phosphate fertilizers or sewage sludges (USPHS 1993). In 1988, an estimated 306,000 kg of cadmium entered the domestic environment as a result... 

Elevated levels of molybdenum in nonbiological materials have been reported near certain mines, power plants, and oil shale deposits, as well as in various sewage sludges, fertilizers, and agricultural drainwaters (Table 30.1). Molybdenum is concentrated in coal and petroleum, and the burning of these fuels contributes heavily to atmospheric molybdenum (King et al. 1973). Combustion of fossil fuels contributes about 5000 metric tons of molybdenum annually to the atmosphere atmospheric particulates contain about 0.001 pg Mo/m3 air (Goyer 1986). 

Stationary sources Waste incineration Steel industry Recycling plants Energy production Municipal solid waste, clinical waste, hazardous waste, sewage sludge Steel mills, sintering plants, hot-strip mills Non-ferrous metals (melting, foundry Al, Cu, Ptx, Zn, Sn) Fossil fuel power plants, wood combustion, landfill gas... 

PCDD/Fs are emitted or spilled from many processes, but as they were found in the emissions from all combustion processes, thermal processes are recognized to be a main source, and a major public concern, especially waste incineration. But dioxins problem is attributed to all human activities, connected either with production or utilization of solid wastes and wastewaters. One of the crucial examples of the problem is sewage sludge contamination. 

Stolarek, R, Ledakowicz, S. 2001. Thermal proeessing of sewage sludge by drying, pyrolysis, gasification and combustion. Water Sci Tech 44 333-339. 

Similarly, polychlorinated dioxins and furans form in both compost and sewage sludge (1), but the major congeners in both systems are heptachloro- and octa-chlorodibenzo-p-dioxins and their origin is not understood (2052-2056). Several studies have attempted to elucidate the importance of natural combustion events as a source of polychlorinated dioxins and furans (1), but recent reports indicate that forest fires may not be a significant source of these compounds (227, 2057) despite earlier suggestions to the contrary (1, 2058, 2059). Nevertheless, numerous studies (wood stoves, control bums, etc.) clearly demonstrate that the combustion of wood... 

More than 5,000 tons of organotins were released, primarily to landfills, in the United States in 1976 (Laughlin and Linden 1985). Additional releases to soil may occur by disposal of fly ash from coal combustion or land application of sewage sludge. 

CDDs have been measured in all environmental media including ambient air, surface water, groundwater, soil, and sediment. While the manufacture and use of chlorinated compounds, such as chlorophenols and chlorinated phenoxy herbicides, were important sources of CDDs to the environment in the past, the restricted manufacture of many of these compounds has substantially reduced their current contribution to environmental releases. It is now believed that incineration/combustion processes are the most important sources of CDDs to the environment (Zook and Rappe 1994). Important incineration/combustion sources include medical waste, municipal solid waste, hazardous waste, and sewage sludge incineration industrial coal, oil, and wood burning secondary metal smelting, cement kilns, diesel fuel combustion, and residential oil and wood burning (Clement et al. 1985 Thoma 1988 Zook and Rappe 1994). 

ND-9.4 ppt). The widespread occurrence of 2,3,7,8-TCDD in U S. urban soils at levels of 0.001-0.01 ppb suggests that local combustion sources, including industrial and municipal waste incinerators, are the probable sources of the trace 2,3,7,8-TCDD soil concentrations found in those locations (Nestrick et al. 1986). Soil samples collected in the vicinity of a sewage sludge incinerator were compared with soil samples from rural and urban sites in Ontario, Canada (Pearson et al. 1990). 

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