High Precision Measurement of Spectroscopic Parameters of H2S at 6320 ~6350cm-1 Band
High Precision Measurement of Spectroscopic Parameters of H2S at 6320 ~6350cm-1 Band
复制标题
DOI：
10.7498/aps.72.20221855
复制
发表时间：
2023
影响因子：
1
通讯作者：
Tian Si-Di;Du Yan-jun;Li Ji-Dong;Ding Yan-Jun;Peng Zhi-Min;Lv Jun-Fu;Pan Chao;Feng Xiao-Ya
中科院分区：
文献类型：
--
作者：
Tian Si-Di;Du Yan-jun;Li Ji-Dong;Ding Yan-Jun;Peng Zhi-Min;Lv Jun-Fu;Pan Chao;Feng Xiao-Ya
硫化氢（H2S）是一种强腐蚀性、剧毒性气体，是化工、能源、环境等领域的重要中间产物或污染物。准确的在线测量其浓度对于过程控制和安全生产具有重要意义。可调谐半导体激光吸收光谱（TDLAS）作为一种定量吸收光谱技术，适用于大气环境和工业过程中H2S浓度的高精度在线测量。考虑到HITRAN 2020数据库中H2S的光谱参数大多基于半经验理论模型计算，缺乏实验数据验证，本文首次采用直接吸收光谱法（DAS）测量了H2S在6320~6350 cm-1波段的吸收光谱。选取了6组吸收较强、相对独立的特征谱线作为实验测量的目标跃迁。然后，采用无需定标、高信噪比的波长调制-直接吸收（WM-DAS）方法，测量了不同压力下6组跃迁的能量密度。将Voigt、Raution和二次速度相关的Voigt谱线对测量的光谱数据进行最小二乘拟合，得到碰撞增宽系数、谱线强度和迪凯窄化系数等光谱参数，其最小标准偏差为7×10-5。谱线强度的测量不确定度小于2%，碰撞增宽系数、迪凯窄化系数和速度相关系数的测量不确定度小于10%。该工作有助于完善H2S光谱数据库，为H2S浓度的高精度测量提供光谱数据基础。
As a highly corrosive and highly toxic gas, hydrogen sulfide (H2S) is an important intermediate product or pollutant in many fields such as chemical industry, energy and environment. Accurate online measurement of its concentration is of great significance for process control and production safety. Tunable diode laser absorption spectroscopy (TDLAS), as a quantitative absorption spectroscopy technique, is suitable for high-precision on-line measurement of H2S concentration in atmospheric environment and industrial processes. Considering that most of the spectroscopic parameters of H2S in the HITRAN2020 database are mainly calculated based on semi-empirical theoretical model and lack of experimental data verification, in this paper, direct absorption spectroscopy (DAS) method was firstly used to measure the absorption spectra of H2S in the band of 6320~6350 cm-1. Six groups of characteristic lines with strong absorption and relative independence were selected as the target transitions for experimental measurement. Then, the wavelength modulation-direct absorption (WM-DAS) method with no calibration and high signal-to-noise ratio was used to measure the absorbances of the six groups of transitions under different pressures. Voigt, Raution and quadratic speed-dependent Voigt profiles were least squares fit to the measured absorbances in order to obtaining the spectroscopic parameters such as the collision broadening coefficient, line strength and Dicke narrowing coefficient, and the minimum standard deviation of residual error of absorbances was 7×10-5. The measurement uncertainty of line strengths were less than 2%, and the uncertainty of collision broadening coefficients, Dicke narrowing coefficients and the speed-dependent coefficients were less than 10%. This work is helpful to improve the H2S spectral database and provide the spectral data basis for the high-precision measurement of H2S concentration.