Morphological and chemical characterization of iron-rich fly ash fractions

Flyash samples collected from the electrostatic precipitator of a coal-fired power plant were separated into magnetic and nonmagnetic fractions. Examination revealed that the flyash particles in the magnetic concentrates were predominantly spherical and were general solid in cross section. The larger particles exhibited the most diversity with respect to internal morphology. A variety of dendritic growths were among the features observed. The magnetic fraction was composed primarily of magnetite and Lesser amounts of hematite. Results suggest a potential for increasing ash density and purity by selecting a particle size range that will optimize these parameters.