Measuring Chemical Air Emissions Using Environmental CAT Scanning

University Of North Carolina At Chapel Hill, Chapel Hill NC

Investigators

Abstract

0001385 Todd The goals of this research are the development and field-testing of an innovative real-time method for measuring, visualizing and quantifying chemical air emissions and emission rates. With the proposed method, two-dimensional pollutant concentration maps of large areas are generated using an environmental CAT (computer assisted tomography) scanning system that couples the chemical detection technology of open-path Fourier transform infrared (OP-FTIR) spectroscopy with the mapping capabilities of computer assisted tomography. In the proposed system, several OP-FTIR spectrometers transmit beams of infrared light along open beam paths (up to one kilometer, approximately) to simultaneously measure and identify a wide range of multiple contaminants directly in the atmosphere, typically at part per billion or part per million detection levels. The tomographic system uses a mathematical image reconstruction algorithm to process the multiple data into two-dimensional chemical maps. If successful, this method will allow concentrations to be spatially resolved in real-time over large areas with fewer measurements than would be required with conventional point samplers to obtain the same level of detail. ***