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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
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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

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