Laser infrared gas analyzer based on TDLAS-WMS (tunable diode laser absorption spectroscopy-wavelength modulation spectroscopy)

Abstract

The invention belongs to the technical field of gas detection and relates to a laser infrared gas analyzer based on TDLAS-WMS (tunable diode laser absorption spectroscopy-wavelength modulation spectroscopy) for detecting hydrogen chloride, methane, carbon monoxide, water vapor and other gases. The laser infrared gas analyzer comprises a laser, a laser driving circuit, a temperature control circuit, an optical system with an optical cavity, a main detector, a reference detector, an intensity modulation and canceling circuit, a phase-locking and amplification circuit and a data acquisition and display circuit, wherein the laser driving circuit and the temperature control circuit are used for controlling the laser to emit light, the two ends of the optical system are respectively connected with the laser and the detector, the intensity modulation and canceling circuit is used for canceling the influence of intensity modulation in the system, the phase-locking and amplification circuit is used for extracting harmonic signals, and the data acquisition and display circuit is used for displaying the concentration of the gas to be detected. Compared with other detection instruments, the laser infrared gas analyzer has the advantages that division operation is introduced into the intensity modulation and canceling circuit, and the laser infrared gas analyzer is combined with a space double-optical path differential detection method, so that the influence of the intensity modulation can be fundamentally canceled.

Description

technical field [0001] The invention belongs to the technical field of gas detection, in particular to a laser infrared gas analysis based on TDLAS-WMS (Tunable Diode Laser Absorption Spectroscopy, TDLAS, Wavelength modulation spectroscopy, WMS) for detecting hydrogen chloride, methane, carbon monoxide, water vapor and other gases instrument. Background technique [0002] Hydrogen chloride is a colorless gas with a pungent odor. Volatile, strong diffusivity, soluble in water. Hydrogen chloride is also an important chemical raw material. Therefore, in the chemical production process, hydrogen chloride waste gas will inevitably be produced. Since hydrogen chloride has a strong stimulating effect on human eyes and respiratory system, it will cause a series of human diseases and even death. . Hydrogen chloride is also harmful to the environment. In order to minimize the impact of hydrogen chloride gas on human production and life, its monitoring is very important. [0003] M...

AI Technical Summary

Problems solved by technology

Aiming at the intensity modulation phenomenon existing in the measurement, the present invention proposes a new solution, that is to use the division operation combined wit...

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