Record Display for the EPA National Library Catalog


OLS Field Name OLS Field Data
Main Title Relationship of fly ash composition, refractive index and density to in-stack opacity /
Author Cowen, S. J. ; Ensor, D. S.
Other Authors
Author Title of a Work
Ensor, D. S.
CORP Author Atmospheric Research Group, Altadena, CA.;Environmental Protection Agency, Research Triangle Park, NC. Air and Energy Engineering Research Lab.
Publisher GPO,
Year Published 1985
Report Number EPA/600/7-85/003
Stock Number PB85-169860
Subjects Fly ash. ; Light absorption.
Additional Subjects Fly ash ; Refractivity ; Density(Mass/volume) ; Opacity ; Air pollution ; Chemical compounds ; Plumes ; Optical properties ; Particles ; Industrial wastes ; Combustion products ; Solid wastes
Library Call Number Additional Info Location Last
NTIS  PB85-169860 Most EPA libraries have a fiche copy filed under the call number shown. Check with individual libraries about paper copy. NTIS 01/01/1988
Collation 66 pages : illustrations
The report gives results of an investigation of the refractive index, density, and composition of fly ash from coal-fired boilers, aimed at determining: (1) the interrelationship of refractive index and composition, and (2) the significance of ash properties on in-stack plume opacity. A survey was made of 14 ash samples representing a wide range of coals. Light absorption was measured using the Integrating Plate Method, which compares light absorption through a clean filter to that through a filter with a single layer of aerosol. Only absorption is measured, while scattered light is integrated equally for both cases. This technique requires fine particles (volume absorbers) for easy interpretation of results. The technique was calibrated using an aerosol, methylene blue, with known absorption characteristics. The real part of the refractive index was measured by an oil immersion technique. The real refractive index and density were found to be highly correlated with composition with a multilinear regression equation. The absorbing refractive index was well correlated with ash carbon content. The modeling of in-stack opacity showed a weak dependence on ash optical properties for the range of ashes studied. The effect of the real part of the refractive index on opacity tends to be counterbalanced by particle density effects. Furthermore, most fly ash absorbs relatively little light.
Caption title. "February 1985." "EPA-600/7-85-003." Microfiche.