针对高炉煤气成分复杂、燃烧效率低、燃烧稳定性差的问题, 提出了基于波长调制光谱(Wavelength Modulation Spectroscopy, WMS)的高炉煤气燃烧场温度测量方法。WMS具有抗噪声能力强、测量精度高和灵敏度好的特点, 适用于高炉煤气燃烧场的温度测量。基于可调谐二极管激光吸收光谱技术的测量特点, 以H2O为目标气体, 选取波长位于1 391.67 nm和1 397.75 nm的吸收谱线, 通过两个激光器时分复用的方式获取两条目标吸收谱线, 对黑体炉和平面火焰燃烧炉进行温度测量, 达到了实验验证的目的。实验结果表明, 所提检测方案对高炉煤气所在500~2 000 K温度范围内都有较高的测量灵敏度, 检测结果线性度优于99%。现场实验验证系统可满足高炉煤气的温度场测量等原位在线测量的应用, 为后续的燃烧优化和节能减排奠定了基础。

Aiming at the problems of composition complexity, low combustion efficiency and poor combustion stability of blast furnace gas, a temperature measurement method of blast furnace gas combustion field based on wavelength modulation spectroscopy(WMS) was proposed. WMS method has the characteristics of strong anti-noise ability, high measurement accuracy and high sensitivity. It was suitable for temperature measurement of blast furnace gas combustion field. Based on the measurement characteristics of tunable diode laser absorption spectroscopy, H2O was taken as the target gas, and its absorption spectral lines at 1 391.67 nm and 1 397.75 nm were selected. Two target absorption lines spectra were obtained by time division multiplexing of two lasers. The temperature measurement of blackbody furnace and flat flame combustion furnace were measured respectively for the experimental verification. The results show that the proposed detection scheme has high sensitivity to the temperature range of 500-2 000 K, and the linearity of the detection results is better than 99%. The field test verified that the system can meet the application of in-situ on-line measurement of blast furnace gas temperature, which lays a foundation for subsequent combustion optimization and energy saving and emission reduction.