近红外长光程激光调制吸收光谱甲烷检测仪  

A methane detection device using near-infrared long-path laser absorption spectroscopy

作　　者：齐海英[1] 郑传涛 QI Hai-ying;ZHENG Chuan-tao(College of Electrical Information,Changchun University of Architecture and Civil Engineering,Changchun 130607,China;State Key Laboratory of Integrated Optoelectronics,College of Electronic Science and Engineering,Jilin University,2699Qianjin Street,Changchun 130012,China;Jilin Provincial Engineering Research Center of Infrared Gas Sensing Technique,2699Qianjin Street,Changchun 130012,China)

机构地区：[1]长春建筑学院电气信息学院,吉林长春130607 [2]吉林大学电子科学与工程学院,集成光电子学国家重点联合实验室吉林大学实验区,吉林长春130012 [3]吉林省红外气体传感技术工程研究中心,吉林长春130012

出　　处：《光电子．激光》2020年第1期21-26,共6页Journal of Optoelectronics·Laser

基　　金：国家重点研发计划课题(2016YFD0700101);国家自然科学基金项目(61775079,61627823,61960206004);吉林省科技发展计划项目(20180201046GX,20190101016JH)资助项目。

摘　　要：甲烷(CH4)是一种温室效应气体且泄漏的甲烷会造成安全隐患,因此实时监测工业生产及大气中CH4浓度尤为重要。根据甲烷分子在近红外波段的吸收特性和长光程激光吸收光谱技术,本文研制了一种基于长光程多通池吸收气室的近红外激光甲烷检测仪。该检测仪的光学系统采用分布反馈激光器作为光源,多通池气室的有效光程为16 m,物理尺寸为58×8×9 cm;在电学系统方面,编写了基于LabVIEW的数据产生、采集与处理程序,用于提取二次谐波信号、标定浓度和开展系统的稳定性测试实验。利用气体混合系统,配备了浓度为10-100×10-6(体积分数)的甲烷气体样品,开展了气体标定与性能测试实验。结果显示,当积分时间为0.1 s时,系统的检测下限约为70×10^-9;当积分时间为100 s时,该系统的检测下限可以降至5×10^-9。Leaked methane(CH4)will not only cause safety hazards but also cause greenhouse effect.Therefore,it is particularly important to monitor the concentration level of CH4 in real time in atmosphere and industrial field.Based on the absorption characteristics of CH4 molecule in the near-infrared region and long-path laser absorption spectroscopy,a near-infrared CH4 sensor system based on long-path multi-pass gas cell was developed.For the optical sub-system of the detection device,a distributed feedback laser was used as the light source,and the effective light path of the multi-pass gas cell was 16 m with a physical size of 58×8×9 cm.In terms of electrical sub-system,a data generation,acquisition and processing program based on LabVIEW was compiled for the second harmonic signal extraction,calibration concentration and stability test.Standard CH4 samples with concentration levels of 10-100 parts-per-million in volume(ppmv)were prepared using a gas mixing system,and sensor calibration and performance measurement were carried out.The results show that the detection limit of the sensor system is 70 parts-per-billion in volume(ppbv)with an averaging time of 0.1 s,and it can be reduced to 5 ppbv with an averaging time of 100 s.

关 键 词：光电检测 红外技术与应用 甲烷检测 多通池气室 

分 类 号：TN21[电子电信—物理电子学]