低碳化学品火焰红外光谱辐射特性研究

低碳化学品火灾事故风险高、危害极大，探究低碳化学品火焰光谱特性对探测识别该类火灾危害污染意义重大，但目前国内外对大型低碳化学品火灾事故产生有毒、有害的硫化物（SO_X）和氮化物（NO_X）气体等相关研究较少。通过搭建1.2～12 μm红外波段火焰光谱测试实验平台，对二硫化碳、92#汽油和酒精进行5，14和20 cm三种不同燃烧尺度火焰光谱测试，探究火焰燃烧尺度对高温火焰分子辐射光谱的影响。随着燃烧尺度的增大，火焰辐射强度增强和特征波段出现增宽现象。分析5 cm 燃烧尺度下四种典型化学品中液化天然气（LNG）、丙烯腈、乙腈和95#汽油不同的火焰光谱特征。通过用傅里叶变换红外光谱仪测量高温黑体炉的不同温度，对火焰光谱信号进行辐射定标，得出准确的辐射定标系数，从而得到高温火焰分子发射的辐射亮度值。并且与HITRAN数据库模拟大气压1 atm、温度1 300 K单一的SO₂，H₂O，CO₂和NO₂分子辐射光谱进行对比分析。其中高温火焰分子光谱主要有7.3～7.6，8.7和4.0 μm SO₂波段、1.8～2.1和6.4 μm H₂O波段和4.2～4.6 μm CO₂波段，以及2.5～2.9 μm H₂O和CO₂共同波段。高温NO₂气体未达到红外光谱仪的检测限，通过HITRAN数据库模拟可知6.0～6.4，3.4和2.4 μm NO₂波段。为了进一步区分各种化学品火焰光谱，对定标后的火焰光谱信号进行归一化处理，用db2小波基函数进行6层分解得到高频部分近似系数和低频部分的细节系数，通过对比不同化学品高温火焰光谱的近似和细节系数的差异。结果表明，二硫化碳火焰光谱特征和小波分析的化学品火焰光谱特征，可作为区分低碳化学品与油料重要依据，并为后续遥感探测低碳化学品特征污染物、组分浓度反演以及识别评估其污染危害奠定重要基础。

Research on the Radiation Characteristics of Low-Carbon Chemical Flame Infrared Spectrum

Low-carbon chemical fire accidents have a high risk and great harm.Exploring the flame spectrum characteristics of low-carbon chemicals is of great significance in detecting and identifying such fire hazards and pollution.However,domestic and foreign large-scale low-carbon chemical fire accidents produce toxic and harmful sulfur Research on SO_X and NO_X gases is rare.In this paper,by building an experimental platform for flame spectrum testing in the 1.2~12μm infrared band,the flame spectrum test of carbon disulfide,92#gasoline and alcohol at three different combustion scales of 5,14 and 20 cm is carried out to explore the effect of flame combustion scale on high-temperature flame molecular radiation The influence of the spectrum.As the combustion scale increases,the flame radiation intensity increases,and the characteristic waveband appears to broaden.Analyze the different flame spectrum characteristics of liquefied natural gas(LNG),acrylonitrile,acetonitrile and 95#gasoline in the four typical chemicals at the 5 cm combustion scale.Using Fourier transform infrared spectrometer to measure the different temperatures of the high-temperature blackbody furnace,the flame spectrum signal is radiated calibration,and the accurate radiant calibration coefficient is obtained,thereby obtaining the radiance value emitted by the high-temperature flame molecules.Moreover,compared with the HITRAN database simulated atmospheric pressure 1 atm,temperature 1300 K single SO₂,H₂O,CO₂,NO₂ molecular radiation spectrum for comparative analysis.Among them,the high temperature flame molecular spectrum mainly has 7.3~7.6,8.7 and 4.0μm SO₂ bands,1.8~2.1 and 6.4μm H₂O bands,4.2~4.6μm CO₂ bands,and 2.5~2.9μm H₂O and CO₂ common bands.The high temperature NO₂ gas did not reach the detection limit of the infrared spectrometer,and the 6.0~6.4,3.4 and 2.4μm NO₂ bands can be known through the HITRAN database simulation.In order to further distinguish the flame spectra of various chemicals,the calibrated flame spectrum signal is normalized,and the db2 wavelet basis function is used for 6-layer decomposition to obtain the approximate coefficients of the high frequency part and the detail coefficients of the low-frequency part,by comparing different chemistry,the approximation and detail coefficient difference of the high-temperature flame spectrum.The results show that the flame spectrum characteristics of carbon disulfide and the chemical flame spectrum characteristics of wavelet analysis can be used as an important basis for distinguishing low-carbon chemicals from oils and for subsequent remote sensing detection of low-carbon chemical characteristic pollutants,component concentration inversion and identification evaluation Its pollution hazards lay an important foundation.