Feasibility Study of Coal Dust Measurement by Light Reflectance Photometry

摘要

This report describes the design, fabrication, and testing of a proto-type instrument that demonstrates the feasibility of determining respirable coal dust concentrations by light reflectance photometry. Coal dust is collected on a filter and the amount collected is continuously monitored by reflectance photometry. Light emission and detection is accomplished by reflective object sensors, which have both light source and detector in one chip. The use of a pulsed light source insures low drift characteristics of the measuring circuitry. The collection of the respirable coal dust on filters facilitates accurate calibration and also allows measurement verification by well-accepted gravimetric methods.