Method and device for automatically eliminating vapor interference in Fourier transform infrared spectroscopy gas detection

Abstract

The invention relates to a method for automatically eliminating vapor interference in Fourier transform infrared spectroscopy gas detection. The method is characterized by comprising the steps of monitoring the vapor concentration in a gas cell in real time from a specified waveband by adopting a tunable laser absorption spectrum technology, automatically introducing pure nitrogen into to-be-detected gas in the gas cell according to the vapor concentration, enabling the vapor concentration of mixed gas in the gas cell to reach a predetermined concentration value, subtracting a vapor reference spectrum under the predetermined concentration acquired in the preliminary measurement by utilizing a subtraction method, eliminating the vapor interference, calculating the concentration of each component in the to-be-detected gas diluted by nitrogen, calculating a dilution ratio of the to-be-detected gas caused by nitrogen according to the vapor concentration values of the gas in the gas cell before and after pure nitrogen is introduced, and calculating the concentration of each component in the to-be-detected gas before being diluted. By adopting the method, the capability of the Fourier transform infrared spectroscopy technology for automatically and rapidly eliminating the vapor interference in the gas detection can be realized, and the unknown polluted gas can be rapidly detected.

Description

technical field [0001] The invention belongs to the field of spectral measurement of a Fourier transform infrared spectrometer, in particular to a method and a device for automatically eliminating water vapor interference in Fourier transform infrared spectroscopic gas detection. Background technique [0002] Industrial development has brought about a substantial increase in my country's gas pollution emissions, posing a great threat to people's health. At present, most of my country's industrial enterprises are in the middle and lower reaches of the value chain, and their investment in pollution monitoring is limited. The detection of many pollution sources mainly falls on the shoulders of environmental monitoring units with limited personnel. This puts forward an urgent need for a method that can conveniently and quickly detect different types of industrial waste gas at the pollution site. [0003] Fourier transform infrared spectroscopy has the advantages of multi-chann...

AI Technical Summary

Problems solved by technology

So far there is no automatic and fast method to eliminate water vapor interference in gas detection, which seriously affects the practicability of Fourier transform spectroscopy in gas detection

[0008] In summary, water vapor interference is unavoidable in the detection of gas pollutants and will seriously affect the measurement of pollutants

Existing methods to eliminate water vapor interference are difficult to meet the needs of rapid measurement

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