Waveband selection within 400-4000 cm(-1) of optical identification of airborne dust in coal mine tunneling face

摘要

Aimed at the optical evaluation of pollution levels caused by rock dust in an underground coal mine tunneling face, the optimal detection line and optical channel were investigated. The spatial distribution of airborne rock dust under local mining and ventilation conditions was simulated by the computational fluid dynamics method; thus, combined with the scattering and absorption properties of dust particles and gas molecules, the spectral transmission characteristics of a polluted atmosphere, including dust aerosols within 400-4000 cm(-1), were obtained. By eliminating the optical background of mine gases, the pure infrared signals of rock dust were further analyzed. Based on the comparison results, the detection line, which is 1.5 m high and 0.3 m away from the right wall, was determined to be the best observation position, and a waveband of 1505-1525 cm(-1) was selected to estimate the dust concentration. In addition, a dual-band detection method was presented, which can simultaneously identify the dust distribution and dispersion. (C) 2016 Optical Society of America