基于非分散红外技术的煤矿井下有害气体定量探测方法研究

煤矿井下有害气体的浓度监测对煤矿生产安全预警至关重要。介绍了一种基于非分散红外光谱技术能够同时定量探测煤矿井下一氧化碳、甲烷等有害气体的方法。入射红外光经过高速旋转的滤光轮,得到各种待测气体相应滤波通道的调制光信号,经怀特池中待测气体吸收后得到各种气体的吸光度。通过非线性最小二乘拟合吸收光与被测气体浓度,得到测量系统的浓度定标曲线,一氧化碳、甲烷和二氧化碳三者定标拟合相关系数分别为0.9992、0.9996和0.9998。分析了系统的测量精度,通过比较样气标准浓度与实测浓度大小,发现所有被测气体的这两组数据的相关性均大于0.998,测量误差均小于5%。实验结果表明,采用非分散红外光谱技术可以实现煤矿井下多组分有害气体的同步精确探测,为扩展煤矿安全预警技术手段提供了参考。

Study on quantitative measurement method of deleterious gases in underground mine using non-dispersive infrared technology

Measurements of deleterious gases in underground mine are very important to coal mine satety. A methoO using non-dispersive infrared technology for simultaneously measuring carbon monoxide and methane under mine was presented. The modulated infrared lights of every measured gas filter channel was gained by rotating a filter wheel, and these lights were absorbed by measured gases. The gas concentration retrieved functions were acquired by nonlinear least square fitting sample concentrations to absorbance of each gas. The fitting correlation coefficients of carbon monoxide, methane and carbon dioxide were respectively 0. 9992, 0. 9996 and 0. 9998. The measured concentrations of three gases retrieved by concentration retrieved functions were compared with their nominal con- centrations and all correlation coefficients were more than 0. 998 and the measuring errors were all less than 5 %. The test results showed that using non-dispersive infrared technology to simultaneously measure deleterious gases under coal mine is feasible, and this technology is a new monitoring method for mine safety.