燃煤电厂波长调制激光吸收光谱氨逃逸测量系统的参数优化研究

Parameter Optimization Study of Wavelength Modulation Spectroscopy Ammonia Escape Measurement System for Power Plants

基于波长调制激光吸收光谱(WMS)技术的气体浓度测量系统是燃煤电厂氨逃逸监测的主要手段。调制深度的选择是影响波长调制激光吸收光谱测量信噪比的关键,设计NH3分子吸收光谱调制参数优化的数值仿真试验,研究发现在200℃伴热条件下,WMS测量系统的最优调制深度为0.2388 cm^(-1)。在-20~500℃的宽温度范围内,随着温度的提高,最优调制深度接近线性的降低,最优调制深度am与摄氏温度T之间的关系可以用公式am=0.2918-3.26514×10^(-4)T+2.28214×10^(-7)T2精确地描述,该结果对燃煤电厂氨逃逸监测系统的调制参数优化具有重要的指导意义。

A gas concentration measurement system based on wavelength modulation spectroscopy(WMS)technology is the main tool for ammonia escape monitoring in coal-fired power plants.In this paper,we designed a numerical simulation experiment to optimize the modulation parameters of NH_3 molecular absorption spectroscopy,and it was found that the optimal modulation depth of WMS measurement system is 0.2388 cm^(-1)under the condition of 200℃.In the temperature range of-20-500℃,the optimal modulation depth decreases nearly linearly with the increase of temperature,and the relationship between the optimal modulation depth,a_m,and the Celsius temperature,T,can be precisely described by the equation a_m=0.2918-3.26514×10^(-4)T+2.28214×10^(-7)T^2.These results are of great significance for the optimization of the modulation parameters of the ammonia escape monitoring system in coal-fired power plants.