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.,
Other Authors
Author Title of a Work
Ensor, David S.,
Publisher Air and Energy Engineering Research Laboratory, Center for Environmental Research Information
Year Published 1985
Report Number EPA/600-S7-85-003
OCLC Number 896879476
Subjects Fly ash. ; Light absorption.
Internet Access
Description Access URL
Library Call Number Additional Info Location Last
EJBD ARCHIVE EPA 600-S7-85-003 In Binder Headquarters Library/Washington,DC 05/09/2018
EJBD  EPA 600-S7-85-003 In Binder Headquarters Library/Washington,DC 10/17/2018
Collation 2 pages ; 28 cm.
"EPA/600-S7-85-003." "April 1985." Caption title. At head of title: Project Summary.
Contents Notes
The refractive index, density, and composition of fly ash from coal-fired boilers was investigated. The goals were to determine: (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. Ony[sp] 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, except for very high carbon ashes, fly ash absorbs relatively little light.