INSTRUMENT FOR MONITORING FINE, RESPIRABLE PARTICULATE MATTER IN FLUE GASES

The flue gases of combustion-type power plants contain small, respirable ash andfume particles which originate from the inorganic species in the fuel. Coalburning power plants, for example, have a notorious reputation for spewing outflue gas particles originating from the mineral mater in the coal. These fluegas particles (10 microns in diameter) must be characterized for two reasons:1) to determine their potential as toxic air emissions; and 2) to determine thefeasibility for controlling the risk. This proposal offers the development ofan instrument that can characterize the particles in flue gases in-situ for sizedistribution, concentration, and composition. The instrument will utilizeFourier Transform Infrared (FT-IR) transmission spectroscopy to measure infraredextinction as a function of wavelength in the forward direction. The measurementis wavelength dependent with regards to the scattering and adsorption componentsof extinction. Therefore, Mie theory analysis can be utilized to interpret thespectral data for particle size distribution and concentration. Composition isobtained by analysis of absorption band position. Phase I will demonstrate fluegas particle characterization by FT-IR measurements of respirable ash in alaboratory suspension cell. Phase II will develop a prototype instrument thatwill be tested on a power plant flue. The end use of the continuous monitor isfor compliance monitoring and measurement of control process effectiveness.