介绍了自行研发的便携式DOAS系统, 该系统基于差分吸收光谱技术(differential optical absorption spectroscopy, DOAS), 并结合了光纤光谱仪和多次反射池技术。 通过采用SO2标准气体和NO2标准气体对系统的精确度及稳定性进行测试, 利用该系统对铜陵市某工业园区的SO2, NO2和苯等污染成分开展了走航观测实验。 结果表明, 在整个测量期间, 以上污染气体在近污染厂区显示了较高的浓度值, SO2的最高浓度为5 023.2 μg·m-3, NO2为2 195.2 μg·m-3, 苯为162.5 μg·m-3。 在吸收光程为12.6 m时, 系统对SO2, NO2和苯的最低检测限分别为67.0, 169.9和30.6 μg·m-3。 该便携式DOAS系统可为工业园区气体泄漏、 无组织排放等气态污染物的应急性及监督性监测和评估提供便捷、 有效的技术手段。

The self-developed portable DOAS instrument based on differential optical absorption spectroscopy(DOAS) and composed of optical fiber spectrograph and multiple-pass cell was introduced. The standard gases of SO2 and NO2 were employed to test the accuracy and stability of the system, and then cruise observation of SO2, NO2 and benzene was carried out using the system in Tongling industrial park. During the entire period, the polluted gases showed high concentrations near the contaminated areas and the maximum concentrations of SO2, NO2 and benzene were 5 023.2, 2 195.2 and 162.5 μg·m-3, respectively. With 12.6 m optical path, the detection limits of SO2, NO2 and benzene were 67.0, 169.9, 30.6 μg·m-3, respectively. The portable DOAS system provides a convenient and effective technique for industrial park about emergency and supervisory monitoring and evaluation of gas leakage and fugitive emissions of gaseous pollutants.