基于激光吸收光谱多点瓦斯监测技术的研究

Study of Multipoint Gas Monitoring Technology Based on Laser Absorption Spectrum

研究了可调谐半导体激光吸收光谱(TDLAS)技术在煤矿多点瓦斯监测中的应用。分析讨论了基于光谱吸收原理的多点瓦斯实时监测系统的设计方案,TDLAS技术、分布式光纤传感技术和时分复用的信号检测技术相结合,实现多点气体浓度的光学传感。提出了在光路中嵌入标定池的方法来反演浓度。通过不同浓度的瓦斯气体对系统性能进行了测试,检测限低于60×10^(-6)。研究表明系统方案可行,该技术具有实时、连续、非接触快速检测的特点,能够满足矿井瓦斯多点安全监测要求。

The application of coal mining gas multipoint monitoring with tunable diode laser absorption spectroscopy （TDLAS） technique is studied. The principle and design scheme of real-time monitoring of multipoint gas concentration system which based on spectroscopy absorption principle is analyzed. The TDLAS technique, distributed fiber sensing technique and time division multiplexing detection technique are integrated to achieve optical sensing of multipoint gas concentration. Considering the requirement of real-time, measurement, a new inversion method by insetting a calibration cell with standard concentration gas into the optical path is introduced. The system＇s performance is tested by measuring gas of different concentrations. The detection limit is below 60 × 10^-6. It proves that the scheme is feasible, and the technology has characteristics of real-time, successive, non-intrusive and fast measurement, so it can meet the requirements of coal mining gas monitoring.