Optical Analysis System Based on Binary Differential Absorption Intensity Reconstruction Combined with Discretization...

Area of Science:

• Analytical Chemistry
• Spectroscopy
• Environmental Monitoring

Background:

• Accurate monitoring of ammonia (NH3) and nitric oxide (NO) is crucial for industrial selective catalytic reduction (SCR) processes.
• Simultaneous measurement of NH3, NO, and temperature using UV-differential optical absorption spectroscopy (UV-DOAS) is challenging due to spectral overlap.

Purpose of the Study:

• To develop an optical analysis system for simultaneous measurement of NH3, NO, and temperature.
• To overcome the spectral overlap limitations in UV-DOAS for complex gas mixtures.

Main Methods:

• A novel optical analysis system based on binary differential absorption intensity reconstruction and discretization variability analysis was developed.
• Spectral mapping and Boolean screening matrices were used to separate NH3 and NO spectra.
• The relationship between temperature and spectral discretization was established.

Main Results:

• The system achieved high parallel measurement accuracy: 3.9% MRE for NH3 (0-50.0 ppm), 3.5% MRE for NO (0-50.0 ppm), and 2.8% MRE for temperature (290.15-773.15 K).
• Three-dimensional field maps of temperature, concentration, and reconstructed optical parameter (ROP) were constructed for simultaneous measurement.

Conclusions:

• This study presents the first report of simultaneous NH3, NO, and temperature measurements using UV-DOAS.
• The developed optical analysis system offers a promising solution for real-time monitoring and regulation of industrial combustion processes.