基于量子级联激光的高精度在线烟气氨分析仪的性能测试研究

A high-sensitivity on-line flue gas ammonia sensor based on quantum cascade lasers

针对目前脱硝工艺控制中氨逃逸测量的问题,介绍了一种基于中红外量子级联激光吸收光谱技术的高温烟气氨分析仪器,具有高线性度和高灵敏度。实验测量结果表明该分析仪响应时间小于30s,测量示值误差优于1%,1s积分时间测量精度达0.07μL/L。与目前主流的近红外激光氨分析仪对比测试表明,中红外激光氨分析仪能够更快速、更准确地响应氨气浓度的变化,不仅能够满足工业现场氨逃逸在线测量的要求,而且使得烟气脱硝过程中的喷氨实时反馈及精准控制成为可能。

An ultra-sensitive high-temperature ammonia analyzer is developed for flue gas denitrification(DeNOx)process control based on the mid-infrared quantum cascade laser(QCL)spectroscopy.The laboratory results show that the analyzer has a response time less than 30 seconds,accuracy better than 1%,and resolution of 0.07μL/L with 1 second integration time.The mid-infrared analyzer responds to changes in ammonia concentration more quickly and accurately compared to the conventional near-infrared laser based ammonia analyzers.The functionality can meet the requirements of online ammonia slip measurement in industry.Besides,the mid-infrared analyzer provides real-time data of ammonia concentration that enables precise control of ammonia injection in the DeNOx process.