TDLAS逃逸氨检测中温度影响的研究  

Temperature Influence in the TDLAS Detection of Escaping Ammonia

作　　者：张增福[1] 邹得宝[1] 陈文亮[1] 赵会娟[1] 徐可欣[1] 

机构地区：[1]天津大学精密测试技术及仪器国家重点实验室,天津300072

出　　处：《光电工程》2014年第6期32-37,共6页Opto-Electronic Engineering

基　　金：国家863高技术项目(2012AA022602);国家重大科学仪器专项(2012YQ 060165)资助

摘　　要：可调谐半导体激光吸收光谱技术(TDLAS)为逃逸氨的现场抽取式的检测提供了可靠的技术手段,现场环境中温度对二次谐波信号影响非常大,必须要对检测的结果进行温度的修正。当温度从25℃变化到250℃时,在Herriott样品池中对100×10-6的NH3进行检测,得到二次谐波光谱图,结果显示二次谐波信号的幅度随温度的升高而减小,线宽趋于平缓。当压力从0 kPa变化到100 kPa时,二次谐波的信号峰值随着压力增加而减小,线宽趋于平缓。根据上述实验结果,给出了温度修正的公式,通过对不同温度下50×10-6浓度的NH3进行修正,来评价公式的可靠性,修正后的最高误差为5.1%,极大地提高了测量的精度,使系统能够适应高温环境下在线抽取式监测需求。Tunable Diode Laser Absorption Spectroscopy （TDLAS） provides a reliable means of on-line detection technology for sampling style escaping ammonia. Since the temperature had great effects on the 2f signal in the field environment, the results must be modified. When the temperature changed from 25℃ to 250℃, the concentrations of 100 × 10-6 NH3 were detected in the Herriott cell and the 2f signals spectrogram were obtained. The results show that the 2f signal intensity decreases and the curve smooth with the temperature rising. When the pressure changed from 20kPa to 100kPa, the results show that the 2f signal intensity decreases and the curve smooth with the pressure rising. According to the above results, the experience formula of temperature correction was raised. The formula reliability was evaluated through the correction of the 50 × 10-6 concentration NH3 in different temperatures, and the error correction was within 5.1%, which greatly improved the precision of the detection. The results show that the system is suitable for online sampling style monitoring in high temperature environment.

关 键 词：可调谐激光吸收光谱(TDLAS) 氨气检测 温度影响 Herriott样品池 

分 类 号：TH711[机械工程—测试计量技术及仪器]