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| Titel: |
Trace Element Geochemistry of the Whitewood Mine Coals in Alberta |
| Auteur: |
Gentzis, Thomas Goodarzi, Fariborz Hickinbotham, Andrew |
| Verschenen in: |
Energy sources. Part A, Recovery utilization and environmental effects |
| Paginering: | Jaargang 18 (1996) nr. 4 pagina's 419-445 |
| Jaar: |
1996-06-01 |
| Inhoud: |
Subbituminous coals, taken from a freshly mined open pit as well as from nine drillholes in the Whitewood Mine, Alberta, were analyzed for their elemental and radionuclide concentration. Furthermore, the coal ash was analyzed for major oxides, and a comparison was made with coals of similar rank and present only 12 km away, in the Highvale Mine. The Whitewood Mine coals are “clean“ by world standards and do not contain any environmentally deleterious elements in excess amounts. They are suitable for utilization, but care should be taken to minimize the negative opacity effects on the electrostatic precipitators (ESPs). The low Na2O content in the coals, particularly in the open-pit samples, may affect ash resistivity. This could result in a decrease in the flow of current and thus a decrease in the precipitator efficiency. Certain trends of major oxides in the coal ash are observed in a north-south direction and are discussed, with particular emphasis on the Na2O distribution in the six coal seams. The Whitewood Mine drillhole samples contain the following mean concentration of elements: As (4.7 ppm), Br (15.1 ppm), CI (21.5 ppm), Co (3.3ppm), Cr (7ppm), Mo (4.8ppm), Na (710ppm), Ca (1.5%), Mn (110 ppm), Th (6 ppm), U (2.5 ppm), V (19.3 ppm), and Sb (0.7ppm). In the surface samples, the mean concentrations of the above elements are as follows: As (4.5 ppm), Br (196.2ppm), CI (38.4ppm), Co (5.4ppm), Cr (200ppm), Mo (16.7ppm), Na (263ppm), Ca (1.4%), Mn (120ppm), Th (5.2ppm), U (1.6ppm), V (14.3ppm), and Sb (0.7ppm). The open-pit surface samples are much enriched in Br, Mo, and Cr, slightly enriched in CI and Co, much depleted in Na, and slightly depleted in Th, U, and V compared to the drillhole samples. Both sets have similar concentrations of As and Mn. There is a slight increase in As concentration in the north and south ends of the pit; a slight increase in a northern direction was also noted for Si, U, and Na. All rare earth elements (REEs) are within the world range for most coals. Compared to the Highvale Mine coals, the Whitewood Mine coals are slightly enriched in As and V; depleted in Br, Cl, Cr, Se, and Sb; and have essentially the same concentration of Co, Mn, U, and radioactwe nuclides. The radioactwe nuclides of the U and Th series present in the surface coals are low and comparable with those in coak from Australia, the United States, and the United Kingdom. Semiquantitatwe mineralogical analysis of the whole coal indicates rhe predomi-nance of quartz and its polymorph cristobalite, followed by kaolinire, mired-layered clays and illite, with minor diopside, zeolite, rhodochrosite, and pyde. The coal ash of the Whitewood Mine coals has low to medium slagging and fouling propensity. |
| Uitgever: |
Taylor & Francis |
| Bronbestand: |
Elektronische Wetenschappelijke Tijdschriften |
Details van artikel 207 van 216 gevonden artikelen
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