Hostname: page-component-cd9895bd7-jn8rn Total loading time: 0 Render date: 2024-12-27T01:49:04.599Z Has data issue: false hasContentIssue false
  • English
  • Français

Transmitted and Reflected Visible Light Microscopy of Two Bituminous Fly Ashes

Published online by Cambridge University Press:  25 February 2011

Donald L. Biggs  and
Joseph J. Bruns
Donald L. Biggs
Affiliation:
Department of Earth Sciences and Ames Laboratory, Iowa State University, Ames, IA 50011
Joseph J. Bruns
Affiliation:
Department of Earth Sciences and Ames Laboratory, Iowa State University, Ames, IA 50011
Get access

Abstract

Fly ashes of high magnetic content taken from two midwestern power plants were examined to determine the mineralogy of the magnetic and nonmagnetic fractions. Fly ash spheres from the magnetic fraction are predominantly composed of ferrite spinel, hematite and silicate glass. The hematite appears to be a replacement product of the original ferrite spinel. Nonmagnetic phases include mullite, lime, small amounts of hematite and silicate glass. Quartz morphology indicates that it did not fuse in the furnace. Mullite and lime have morphologies indicative of crystallization in the furnace. Hematite is bonded to the nonmagnetic particles or as a complete replacement of ferrite spinel spheres.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 43: Symposium M – Fly Ash and Coal Conversion By-Products I , 1984 , 21
Copyright
Copyright © Materials Research Society 1985

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. Jarrige, A. 1970. Research in the area of fly ash. United States Bureau of Mines Information Circular 8488: 220–236.Google Scholar
2. Murtha, M. J. and Burnet, G. 1978. Power plant fly ash as a source of alumina. Presented at the Sixth Mineral Waste Utilization, Chicago, Illinois.Google Scholar
3. Murtha, M. J. and Burnet, G. 1978. New developments in the lime-soda sinter process for recovery of alumina from fly ash. Ames Laboratory USDOE and Department of Chemical Engineering, Iowa State University, paper No. IS-M-177.Google Scholar
4. Murtha, M. J. and Burnet, G. 1978. The magnetic fraction of coal fly ash: Its separation, properties and utilization. Proceedings of the IowaAcademy of Science 85: 10–13.Google Scholar
5. O'Gorman, J. V. and Walker, P. L. 1971. Mineral matter characteristics of some American coals. Fuel 50: 136–151.Google Scholar
6. O'Gorman, J. V. and Walker, P. L. 1973. Thermal behavior of mineral fractions separated from selected American coals. Fuel 52: 71–79.Google Scholar
7. Roy, N. K., Murtha, M. J., and Burnet, G. 1979. Use of the magnetic fraction of fly ash as a heavy medium material in coal washing. Proceedings of the 5th International Ash Utilization Symposium, Atlanta, Ga.Google Scholar
8. Roy, N. K., Murtha, M. J., and Burnet, G. 1978. Recovery of iron oxide from power plant fly ash by magnetic separation. International Conference on Industrial Applications of Magnetic Separators, Rindge, New Hampshire.Google Scholar
9. Minnick, J. I. 1961. The application of the Roto-Flux Magnetic Separator to pulverized coal fly ash. American Society of Mechanical Engineers. Paper No. 61-WA-313.Google Scholar
10. Colombu, U., Fagherazzi, G., Gazzarrini, F., Lanzavecchia, G., and Sironi, G. 1964. Mechanisms in the first stage of oxidation of magnetite. Nature 202: 175–176.10.1038/202175a0Google Scholar
11. Columbu, U., Fagherazzi, G., Gazzarrini, F., Lanzavecchia, G., and Sironi, G. 1965. Magnetite oxidation: a proposed mechanism. Science 147: 1033.10.1126/science.147.3661.1033Google Scholar
12. Hurst, V. J. and Styron, R. W. 1976. Fly ash for use in the industrial extender market. AMAX Resource Recovery Systems, Inc., Smyma, Georgia.Google Scholar
13. Keyser, T. R., Natusch, D. F. S., Evans, C. A., and Linton, R. W. 1978. Characterizing the surfaces of environmental particles. Environmental Science and Technology 12, No. 7: 768–773.Google Scholar
14. Lauf, R. J. Microstructures of Coal Fly Ash Particles. Ceramic Bulletin 61: 4, 487–490.Google Scholar
15. Watt, J. D. and Thorne, J. 1965. Composition and pozzolanic properties of pulverized fuel ashes I. Composition of fly ashes from some British power stations and properties of their component particles. Journal of Applied Chemistry 15: 585–594.10.1002/jctb.5010151207Google Scholar
16. Biggs, D. L. and Lindsay, C. G. 1984. High temperature interactions among minerals occurring in coal. American Chemical Society, Division of Fuel Chemistry Symposium, Chemistry of mineral matter and ash in coal, In press.Google Scholar
17. Lightman, P. and Street, P. J. 1968. Microscopical examination of heat treated pulverized coal particles. Fuel 47: 1, 7–28.Google Scholar
18. Ramsden, A. R. 1968. Application of electron microscopy to the study formation. Journal of the Institute of Fuel: 451–454.Google Scholar