Separation and analysis method of overlapping absorption spectra with cross interference in gas mixture measurement

doi:10.7498/aps.70.20210286

	Separation and analysis method of overlapping absorption spectra with cross interference in gas mixture measurement
	Wang Qian-Jin 3,4; Sun Peng-Shuai 4; Zhang Zhi-Rong 1,3,4,5; Zhang Le-Wen 4,6; Yang Xi 3,4; Wu Bian 4; Pang Tao 4; Xia Hua 4; Li Qi-Yong 2
刊名	ACTA PHYSICA SINICA
	2021-07-20
卷号	70
关键词	tunable diode laser absorption spectroscopy (TDLAS) gas mixture overlapping spectral lines support vector regression
ISSN号	1000-3290
DOI	10.7498/aps.70.20210286
通讯作者	Zhang Zhi-Rong(zhangzr@aiofm.ac.cn)
英文摘要	The interference between overlapping gas absorption lines often occurs in the measurement of multicomponent gas mixture with using tunable diode laser absorption spectroscopy (TDLAS). This is also the main problem of the technology in some applications. For instance, in the early application of multi-component gas mixture measurement in coal mines, we found that the absorption lines of carbon monoxide (CO) and methane (CH4) seriously overlapped. The absorption signal of trace CO gas was annihilated and could not be effectively demodulated, especially in the presence of high concentration of CH4. This problem could not be solved just by accurately selecting the spectral lines due to the band absorption of CH4. Therefore, in this paper, we introduce the support vector regression (SVR) model to deal with the interference between CO and CH4 absorption lines. The spectral signals of 14 groups of mixed gases with different concentrations of CO and CH4 are used as the training sets, and the five-fold cross-validation is adopted to prevent the model from overfitting. After 15 iterations in 30 seconds, the optimal regression model of CO and CH4 can be obtained respectively. Furthermore, it is worth noting that based on the experimental data, the linear kernel function is selected to construct the two gas SVR models, and the parameters of the SVR models are optimized by the sequential minimal optimization(SMO) algorithm. With the assistance of the SVR models, the absorption spectra of the two gases can be demodulated effectively, and finally the accurate measurement results are obtained. The measurement results show that the absolute error of trace CO and CH4 concentration(volume fraction of gas) are less than 2 x 10(-6) and 0.2 x 10(-2) respectively. Meanwhile, the correlation coefficient between the measured values and the actual values of CO and CH4 are 0.998 and 0.9995, respectively. In addition, the dynamic stability for each of the two regression models is fully verified by the experiment of the inflation process. Consequently, this method can eliminate the interference between the overlapping spectra, and can fully meet the requirements for accurately measuring the gas mixture. We hope that the SVR model can provide an effective solution for the real-time monitoring of multi-component gas mixture, and thus greatly improving the adaptability of TDLAS technology in the future.
资助项目	National Natural Science Foundation of China[11874364] ; National Natural Science Foundation of China[41877311] ; National Natural Science Foundation of China[42005107] ; National Key Research and Development Program of China[2017YFC0805004] ; Key Research and Development Projects of Anhui Province, China[201904c03020005] ; Spark Fund Project of Hefei Institutes of Physics Science, Chinese Academy Sciences, China[YZJJ2020QN8]
WOS关键词	DIODE-LASER ; WAVELENGTH ; CO2
WOS研究方向	Physics
语种	英语
出版者	CHINESE PHYSICAL SOC
WOS记录号	WOS:000677544100016
资助机构	National Natural Science Foundation of China ; National Key Research and Development Program of China ; Key Research and Development Projects of Anhui Province, China ; Spark Fund Project of Hefei Institutes of Physics Science, Chinese Academy Sciences, China
内容类型	期刊论文
源URL	[http://ir.hfcas.ac.cn:8080/handle/334002/123221]
专题	中国科学院合肥物质科学研究院
通讯作者	Zhang Zhi-Rong
作者单位	1.Natl Univ Def Technol, Adv Laser Technol Lab Anhui Prov, Hefei 230037, Peoples R China 2.Monitoring Ctr Ecol & Environm Anhui Prov, Hefei 230071, Peoples R China 3.Univ Sci & Technol China, Sch Environm Sci & Optoelect Technol, Hefei 230026, Peoples R China 4.Chinese Acad Sci, Anhui Inst Opt & Fine Mech, Hefei Inst Phys Sci, Anhui Prov Key Lab Photon Devices & Mat, Hefei 230031, Peoples R China 5.Chinese Acad Sci, Anhui Inst Opt & Fine Mech, Hefei Inst Phys Sci, Key Lab Environm Opt & Technol, Hefei 230031, Peoples R China 6.Univ Sci & Technol China, Hefei 230022, Peoples R China
推荐引用方式 GB/T 7714	Wang Qian-Jin,Sun Peng-Shuai,Zhang Zhi-Rong,et al. Separation and analysis method of overlapping absorption spectra with cross interference in gas mixture measurement[J]. ACTA PHYSICA SINICA,2021,70.
APA	Wang Qian-Jin.,Sun Peng-Shuai.,Zhang Zhi-Rong.,Zhang Le-Wen.,Yang Xi.,...&Li Qi-Yong.(2021).Separation and analysis method of overlapping absorption spectra with cross interference in gas mixture measurement.ACTA PHYSICA SINICA,70.
MLA	Wang Qian-Jin,et al."Separation and analysis method of overlapping absorption spectra with cross interference in gas mixture measurement".ACTA PHYSICA SINICA 70(2021).