基于中红外吸收光谱的长光程仪器在环境空气监测中的应用

Application of long-path air monitoring instrument based on mid-infrared absorption spectroscopy in ambient air monitoring

介绍了一种基于中红外吸收光谱的高灵敏长光程环境空气监测仪器,对其进行了实验室性能测试,并与点式化学发光法仪器进行了对比测试。实验室测试结果表明,长光程仪器的NO、NO_2和NH_3的零点和量程漂移均小于±1%F.S./24 h,示值误差均小于0.5%,重复性小于1%,稳定性小于±2.5%。现场比对测试结果表明,长光程和点式仪器对NO和NH_3的测量结果基本一致,NO2测量值的变化趋势基本一致,但是存在一定差异。

It presents a high - sensitivity long - path ambient air monitoring instrument based on mid - infrared ab- sorption spectroscopy, which conducted a laboratory performance test and a comparison test on site compared with point chemiluminescence method instrument. The results show that the zero point and range drift of NO, NO2 and NH3 for long optical path instrument is less than ±1% F. S./24h,the indication error is less than 0. 5%, repeatability is less than 1% ,and stability is less than ±2.5%. Comparison test on site results show that measurements on the NO and NH3 of long optical path instrument and chemiluminescence method instrument are basically the same, the trend of NO2 measurement is basically the same but a certain difference is there.