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Applied Optics

Applied Optics


  • Vol. 38, Iss. 27 — Sep. 20, 1999
  • pp: 5710–5723

Model of the diffuse reflectivity of fly ash and its application to an optical sensor system for the determination of carbon in fly ash

Alexander Schneider  »View Author Affiliations

Applied Optics, Vol. 38, Issue 27, pp. 5710-5723 (1999)

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Fly ash, a fine gray powder, is filtered out of the flue gas in coal-fired power stations. It consists of silicon oxide, metal oxides, and unburned carbon. An optical sensor system for measurement of the carbon content of fly ash is described. Based on a mathematical model, an algorithm is deduced that allows the carbon content to be calculated from two measurements of the diffuse reflectivity of a fly ash sample before and after a surface-grinding process. In this model the fly ash sample is assumed to be composed of three types of cube: light-scattering cubes, soft absorbing cubes (carbon), and hard absorbing cubes (iron oxide).

© 1999 Optical Society of America

OCIS Codes
(000.3860) General : Mathematical methods in physics
(120.1740) Instrumentation, measurement, and metrology : Combustion diagnostics
(120.1840) Instrumentation, measurement, and metrology : Densitometers, reflectometers
(120.5700) Instrumentation, measurement, and metrology : Reflection
(160.4760) Materials : Optical properties
(240.6490) Optics at surfaces : Spectroscopy, surface

Original Manuscript: January 5, 1999
Revised Manuscript: April 23, 1999
Published: September 20, 1999

Alexander Schneider, "Model of the diffuse reflectivity of fly ash and its application to an optical sensor system for the determination of carbon in fly ash," Appl. Opt. 38, 5710-5723 (1999)

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