Experiment Study of continuous emission monitoring system based on Differential Optical Absorption Spectroscopy

Differential optical absorption spectroscopy (DOAS) technique is based on the recording of the difference between local maxima and minima in the absorption of the probed gas species. An interesting application of the DOAS is to use for the power plant flue gas continuous emission monitoring system. It makes use of the flue gas pollutant different optical absorption characteristic at the UV-VIS wave band to measure their average density and categories. By DOAS principle, experimental study was carried out measuring different concentration SO2, NO2 and NO. The DOAS technology can eliminate the influence of dust etc. The DOAS can be applied to monitor the flue gas emission concentration and should correct the temperature effect on flue gas differential absorption characteristic.