Study on Trace Detection Method of Ammonia Escape Based on TDLAS

摘要

The accurate and fast monitoring of ammonia escape after the flue gas denitrification can be carried out to avoid the two pollution of the environment. It is one of the key work in the field of industry and environmental protection. Based on tunable diode laser absorption spectroscopy (TDLAS), the method for trace detection of ammonia escape was proposed, and the principle of TDLAS was introduced, and the experimental system of tunable diode laser absorption spectroscopy for trace detection of ammonia escape was built. The 1512nm single absorption spectrum was chosen as the target line. Combining the two harmonic technology and wavelength fast scanning technology, the accuracy, linearity, repeatability and fluctuation of the DFB laser were measured by using different concentrations of ammonia gas, and the detection limit was 26ppbv. The experimental results show that TDLAS has high sensitivity, high accuracy and good stability, and it meets the requirement of fast trace detection of ammonia escape.