| Abstract: | Fly ash quality, both as the amount of petrographically distinguishable carbons and in chemistry, varies in both time and space. Temporal variations are a function of a number of variables. Variables can include variations in the coal blend organic petrography, mineralogy, and chemistry; variations in the pulverization of the coal, both as a function of the coal‘s Hardgrove grindability index and as a function of the maintenance and settings of the pulverizers; and variations in the operating conditions of the boiler, including changes in the pollution control system. Spatial variation, as an instantaneous measure of fly ash characteristics, should not involve changes in the first two sets of variables listed above. Spatial variations are a function of the gas flow within the boiler and ducts, certain flow conditions leading to a tendency for segregation of the less-dense carbons in one portion of the gas stream. Caution must be applied in sampling fly ash. Samples from a single bin, or series of bins, m ay not be representative of the whole fly ash, providing a biased view of the nature of the material. Further, it is generally not possible to be certain about variation until the analysis of the ash is complete. ?? 2001 Elsevier Science B.V. All rights reserved. |
| Genre: | Article |
| ProdID: | 70023083 |
| Citation Author: | Hower, J. C.; Trimble, A. S.; Eble, C. F. |
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| Citation End Page: | 58 |
| Citation Issue: | 1 |
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| Citation Language: | English |
| Citation Larger Work Title: | Fuel Processing Technology |
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| Citation Number Of Pages: | 22 |
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| Citation Search Results Text: | Temporal and spatial variations in fly ash quality; 2001; Article; Journal; Fuel Processing Technology; Hower, J. C.; Trimble, A. S.; Eble, C. F. |
| Citation Start Page: | 37 |
| Citation Volume: | 73 |
| Citation Year: | 2001 |
| Type: | citation/reference |
| Text: | Temporal and spatial variations in fly ash quality; 2001; Article; Journal; Fuel Processing Technology; Hower, J. C.; Trimble, A. S.; Eble, C. F. |
| URL (THUMBNAIL): | http://pubs.er.usgs.gov/thumbnails/outside_thumb.jpg |
| URL (DIGITAL OBJECT IDENTIFIER): | http://dx.doi.org/10.1016/S0378-3820(01)00193-X |
| Date Other: | Mon, 1 Jan 2001 00:00 -0600 |
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