Ash disposal

Ash content is also important. Ash discharge at high temperature, as molten ash from a slagging boiler, involves substantial amounts of sensible heat. However, the higher cost of washed coal of lower (about 10%) ash content does not always merit its use. Ash disposal and extra freight costs for high... 

Ultimate analysis-an analysis to determine the amounts of basic feed constituents. These constituents are moisture, oxygen, carbon, hydro- gen, sulfur, nitrogen, and ash. In addition, it is typical to determine chloride and other elements that may contribute to air emissions or ash- disposal problems. Once the ultimate analysis has been completed, Dulong s formula can be used to estimate the heating value of the sludge, Dulong s formula is ... 

Similar to Alternative 3 incinerator ash disposed in municipal landfill. If metals are present in Area 2, incinerator ash would be disposed in RCRA landfill. Incineration very reliable because material is... 

Lake Erie near coal ash disposal basin 1983-84 ... 

Hatcher, C.O., R.E. Ogawa, T.P Poe, and J.R.P. French, III. 1992. Trace elements in lake sediment, macrozoobenthos, and fish near a coal ash disposal basin. Jour. Freshwater Ecol. 7 257-269. 

Thus they not only minimized the ash disposal problem at coalburning power plants but had reduced substantially the primary contributor to air pollution. (48) By 1966, because of favorable technical and economic analyses and a continually deteriorating balance between petroleum consumption and domestic production, Spencer decided to expand its program. (49)... 

Cost includes vendor profit but excludes waste excavation, feed preparation, and ash disposal. Cost includes vendor profit, waste excavation, and feed preparation but excludes ash disposal. Cost excludes vendor profit, waste excavation, feed preparation, and ash disposal. 

The concern is that the combustion process mobilizes the major/minor and trace element concentrations of combustion product and that fresh water (streams, lakes) as well as ground-water may become contaminated by leachate. In general, sites for ash disposal are physically close to the combustion site. Thus, the location is chosen primarily on the basis of economics, and the disposal sites exhibit a wide range of local hydrological regimes and are, of course, subject to prevailing climatic conditions. 

Simsiman, G. V., Chesters, G. A. Anders, W. 1987. Effect of ash disposal ponds on ground-water quality at coal-fired power plant. Water Research, 21, 417-426. 

However, test bums that were conducted at a single facility to study the effects of adding TDF to a base fuel reveal chemical trends that may be similar to those observed at other facilities, and thus could be useful for assessing ash disposal and groundwater protection strategies. 

The emphasis in the present work is on leachates derived from fly ash disposal, but it must not be forgotten that fine ash particles may escape from power plants. The transport and dispersion of particulate emissions from tall stacks has been actively researched over the last 20-30 years. A review by Carras (1995) records that plumes have been observed to remain as coherent units up to distances of at least 1800 km and thus deposit pollution far from source. However, maximum particulate surface loadings are likely to be found adjacent to old power plants with limited fine-particle fly ash entrapment. Evans et al. (1980) estimated that in a period of 23 years the cumulative stack ash load at a distance of 1.7 km from an 83 MW... 

The leaching behaviour of fly ash is of considerable interest in horticulture, and the literature is extensive. In addition to the reclamation of fly ash disposal sites, fly ash is used extensively as a soil conditioner. Acidic agricultural soils benefit from the addition of alkaline fly ash, and essential plant nutrients present in the ash, such as B, Ca, Mg, K, S, Mn, and Zn are also added improving both chemical and physical properties (Clark et al. 1995 Sikka Kansal 1995). In coal mining areas, acid mine drainage... 

Batch leaching tests are generally taken as an initial step to evaluate toxicity of the ashes because the batch tests represent the best leaching conditions and generate the highest quantity of leachates (Benito et al. 2001). Serial batch leaching tests also often successfully simulate ash pond conditions (Praharaj et al. 2002), whereas the column leaching tests simulate dry ash disposal (Benito et al. 2001). 

Fig. 2. Variation of major elements in porewaters as a function of depth in the Barlow (open circles) and Meaford (solid circles) ash disposal mounds.

Choi, S.-K., Lee, S., Song, Y.-K. Moon, H.-S. 2002. Leaching characteristics of selected Korean fly ashes and its implications for the groundwater composition near the ash disposal mound. Fuel, 81, 1083-1090. 

Hardy, M. A. 1981. Effects of Coal-Fly Ash Disposal on Water Quality in and around the Indiana Dunes National Lake-Shore, Indiana. Water-Resources Investigations, 81-16. USGS Indianapolis. 

Sakata, M. 1987. Movement and neutralization of alkaline leachate at coal ash disposal. Environmental Science and Technology, 21, 771-777. 

Theis, T. L., Westrick, J. D., Hsu, C. L. Marley, J. J. 1978. Field investigation of trace metals in groundwater from fly ash disposal. Journal of Water Pollution Control Federation, 50, 2457-2469. 

Although Eh (redox potential) can affect both the adsorption/desorption reactions that can occur as well as the secondary phases that can form during CCB weathering, Theis Richter (1979) stated that their studies of ash disposal ponds showed that oxidizing conditions rather consistently prevail in the active leaching zone (i.e., the unsaturated zone above the water table). 

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