Hostname: page-component-78c5997874-8bhkd Total loading time: 0 Render date: 2024-11-10T08:46:39.195Z Has data issue: false hasContentIssue false

Speciation in Size and Density Fractionated Fly Ash II. Characterization of a Low-Calcium, High-Iron Fly Ash

Published online by Cambridge University Press:  25 February 2011

R. T. Hemmings
Affiliation:
Ontario Research Foundation, Sheridan Park, Mississauga, Ontario, Canada, L5K 1B3.
E. E. Berry
Affiliation:
Ontario Research Foundation, Sheridan Park, Mississauga, Ontario, Canada, L5K 1B3.
B. J. Cornelius
Affiliation:
Ontario Research Foundation, Sheridan Park, Mississauga, Ontario, Canada, L5K 1B3.
B. E. Scheetz
Affiliation:
Materials Research Laboratory, The Pennsylvania State University, University Park, PA 16802
Get access

Abstract

Morphological, chemical and mineralogical speciation of a low-Ca, high-Fe fly ash from a bituminous coal has been investigated by examination of size, density and magnetic fractions. Fractionation by size revealed little information as to speciation among particle types. However, separation of the ash into eight density fractions and into magnetic and non-magnetic components showed major differences in particle properties. It was found that glasscontaining particles can be divided into three general types: Type 1, being low-Fe content, low-density hollow spheres comprising aluminosilicate/mullite glass ceramics; Type 2, of intermediate density, being ferroaluminosilicate/ mullite glass ceramics; and Type 3, high density composite particles of spinel/hematite crystals embedded in an iron-substituted glass. It is proposed that Type 1 and Type 2 particles are derived from thermal decomposition of clay minerals with a range of Fe contents. Type 3 particles are considered to arise from thermal decomposition of pyrite in the presence of small quantities of aluminosilicate minerals. Two general types of glass were distinguished: Glass I(f), being largely a low-iron aluminosilicate; and Glass II(f), being a ferroaluminosilicate of high Fe-content. XRD and vibrational spectroscopic evidence suggest that, in both glass types, Fe is substituted for Al in an aluminosilicate-type structure.

Type
Research Article
Copyright
Copyright © Materials Research Society 1987

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

REFERENCES

1. Jackson, P.J., J. Appl. Chem. 7, 605 (1957).Google Scholar
2. Simons, H.S. and Jeffery, J.W., J. Appl. Chem. 10, 328 (1960).Google Scholar
3. Watt, J.D. and Thorne, D.J., J. Appl. Chem. 15, 585594 (1965).Google Scholar
4. Lauf, R.J., Bull. Am. Ceram. Soc. 61 (4), 487490 (1982).Google Scholar
5. Hulett, L.D. and Weinberger, A.J., Env. Sci. Technol. 14, 965970 (1980).Google Scholar
6. Lauf, R.J., Harris, L.A. and Rawlson, S.S., Env. Sci. Technol., 16, 218220 (1982).Google Scholar
7. Hinkley, C.C., Smith, G.V., Twardowska, H., Saporoschenko, M., Shirley, R.H. and Griffen, R.A., Fuel 59, 161 (1981).Google Scholar
8. Huggins, F.E., Kosmack, D.A. and Huffman, G.P., Fuel 60, 577 (1981).Google Scholar
9. Huffman, G.P., Huggins, F.E. and Dunmyre, G.R., Fuel 60, 585 (1981).Google Scholar
10. Aiken, T.L.H., Cashion, J.D. and Oltrey, A.L., Fuel 63 12691275 (1984).Google Scholar
11. Biggs, D.L. and Bruns, J., in Fly Ash and Coal Conversion By-Products: Characterization, Utilization and Disposal I, edited by McCarthy, G.J. and Lauf, R. J., Mat. Res. Soc. Symp. Proc. Vol.43 (Materials Research Society, Pittsburgh, 1985), pp. 2129.Google Scholar
12. Diamond, S., Cem. Concr. Res. 16, 569579 (1986).Google Scholar
13. Norton, G.A., Markuszewski, R. and Shanks, H.R., Env. Sci. Technol. 20, 409413 (1986).Google Scholar
14. Hemmings, R.T. and Berry, E.E., in Fly Ash and Coal Conversion By-Products: Characterization, Utilization and Disposal II, edited by McCarthy, G.J., Glasser, F.P. and Roy, D.M., Mat. Res. Soc. Symp. Proc. Vol.65 (Materials Research Society, Pittsburgh, 1986) pp. 91104.Google Scholar
15. van Roode, M. and Hemmings, R.T., CANMET Contract Report, No. ISQ83–00162, July 1985.Google Scholar
16. Scheetz, B.E. and White, W.B., in Fly Ash and Coal Conversion By-Products: Characterization, Utilization and Disposal I, edited by McCarthy, G.J. and Lauf, R.J., Mat. Res. Soc. Symp. Proc. Vol.43 (Materials Research Society, Pittsburgh, 1985), pp. 5360.Google Scholar
17. Scheetz, B.E., White, W.B. and Adar, F., in Advances in Materials Characterization II, edited by Synder, R.L., Condrate, R.A. and Johnson, P.E., Materials Science Research Vol.19 (Plenum Press, N.Y. 1985) pp. 145154.Google Scholar
18. Muan, A., J. Am. Ceram. Soc. 40, 420431 (1957).Google Scholar