Application of the Least Squares Fitting in Mine Optical Fiber Carbon Dioxide Monitoring System

Abstract:

Carbon dioxide is one of the important signature gases in spontaneous combustion forecasting of coal goaf area. In the mine limited ventilation environment, concentration of CO2 directly affects the health of coal mines. So a new application of the least squares fitting method in Coal Mine gas monitoring was introduced. The optical fiber CO2 monitoring system which based on this method and tunable diode laser absorption spectroscopy (TDLAS) technology was used in Coal Mine beam tube system, and selected a near-infrared wavelength 1609.117nm fiber-coupled distributed feedback laser (DFB) as light source. Goaf area gas concentrations were directly calculated by the least squares fitting method which also simplified the calibration operation that used only one point to calibrate. Compared to electronic CO2 detector, this improved system has very high detection accuracy and stability. In the condition of 1.4m gas cell, the minimum detectable concentration is 0.05%, and the minimum detectable spectral absorption rate can up to , response time≤60s.

• Periodical: Applied Mechanics and Materials (Volumes 278-280)
• Pages: 983-987
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.278-280.983
• Online since: January 2013
• Authors: Ting Ting Zhang, Xin Wang, Yu Bin Wei, Chang Wang, Tong Yu Liu
• Keywords: Beam Tube System, Carbon Dioxide Monitoring, Coal Goaf Area, Least Square Fitting, Spontaneous Combustion, Tunable Diode Laser Absorption Spectroscopy

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