基于太阳光谱的FTIR技术监测石油化工区丙烯的浓度分布

介绍了一种基于太阳光谱的傅里叶变换红外光谱(FTIR)技术实时监测石油化工区丙烯浓度分布情况的新方法和非线性最小二乘法反演污染气体浓度的算法。利用自主研发的车载FTIR系统对预监测污染源区域做闭合环路测量获取背景参考谱、测量谱,同时应用气体辐射传输的简化模型计算得到大气透过率谱,最终应用非线性最小二乘拟合算法对大气透过率谱反演得出污染源区域周边污染气体分布的柱浓度信息。运用此方法实际遥测了上海高桥石油化工区丙烯排放的情况,实验结果显示,测量的丙烯柱浓度分布准确地反应了污染物的排放和扩散情况,证明了车载FTIR技术在区域性污染气体监测方面的实用性。

Application of Fourier Transform Infrared Spectroscopy Based on Sun Spectrum to Monitor the Distribution of Propylene from Petrochemical Industry

In the paper, a new method is introduced for real-time monitoring the column concentration of propylene from petrochemical industry, which is based on the technique of Fourier Transform Infrared Spectroscopy (FTIR) by using sun spectrum. The retrieval algorithm of the concentrations of polluted gases based on nonlinear least squares is proposed. Continuous measurements surrounding the pre-monitoring contaminated areas are performed with a closed loop by using self-developed vehicular FTIR system to obtain the regional background reference spectrum, measured spectrum,while application of a simplified gas radiative transmission model to calculate atmospheric transmittance spectrum, and finally using the nonlinear least squares fitting algorithm for atmospheric transmittance spectrum to achieve the column concentration of propylene surrounding polluted areas. Using this method, remote sensing experiment of propylene in Shanghai Gaoqiao petrochemical zone was done. The experimental result shows that the measured column concentration distribution of propylene well reflects the pollutant’s emission and dispersion and proves the availability of the vehicular FTIR technology in monitoring regional gas pollution.