Acta Optica Sinica, Volume. 41, Issue 7, 0703002(2021)
Detection Technology of H2S and CO2 Based on Fiber Amplifier Enhanced Photoacoustic Spectroscopy
High-concentration CO2 has a great impact on the accuracy of H2S detection. Thus, this paper proposed a H2S and CO2 detection system based on fiber amplifier enhanced photoacoustic spectroscopy. A single distributed feedback (DFB) laser in series with a high-power erbium-doped fiber amplifier (EDFA) was taken as the photoacoustic excitation source for the high-precision detection of H2S and CO2 simultaneously. In addition, we analyzed the interference of CO2 on H2S detection at the selected H2S absorption line and corrected the measured H2S concentration with the detected CO2 concentration. The results show that the deviation of the corrected H2S concentration remains within -5% to 5%. Moreover, we used Allan variance analysis to calculate the detection limit of the system. When the integral time is 1 s, the detection limits to H2S and CO2 are 656.3×10 -9 and 25.2×10 -6, respectively; when the time is 100 s, the detection limits can reach 61×10 -9 and 2.6×10 -6, respectively. For trace H2S detection, the normalized noise equivalent absorption (NNEA) coefficient is calculated to be 5.5×10 -9 cm -1·W·Hz -1/2. In conclusion, the proposed system has high detection accuracy and good stability.
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Fengxiang Ma, Yu Tian, Ke Chen, Bo Zhang, Chenxi Li, Guangyin Zhang, Min Guo, Beilei Yang, Yue Zhao. Detection Technology of H2S and CO2 Based on Fiber Amplifier Enhanced Photoacoustic Spectroscopy[J]. Acta Optica Sinica, 2021, 41(7): 0703002
Category: COHERENCE OPTICS AND STATISTICAL OPTICS
Received: Oct. 15, 2020
Accepted: Nov. 17, 2020
Published Online: Apr. 11, 2021
The Author Email: Chen Ke (chenke@dlut.edu.cn)