Laser gas analyzer for multicomponent multiplexing measurement

Abstract

The invention discloses a laser gas analyzer for multicomponent multiplexing measurement, comprising a laser driving control circuit, three packaged lasers, an optical fiber beam combiner, a collimating lens, an optical receiving module and a signal processing and display module, wherein the laser driving control circuit modulates and drives the three packaged lasers to emit different laser light rays needing to be modulated in wavelength; the laser light emitted by each packaged laser is transmitted through a single-mode optical fiber; the single-mode optical fibers are combined into an optical fiber beam through the optical fiber beam combiner; the laser light is emitted from the tail part of the optical fiber beam, and enters into the optical receiving module for collection and light-splitting detection after collimation in the collimating lens; and a signal obtained after light-splitting detection is transmitted to the signal processing and display module for processing so that real-time concentrations of a plurality of gases needing to be detected can be obtained. According to the invention, multiplexing detection is carried out on the laser lights with various wavelengths in an optical fiber beam mode; and such a method is capable of effectively avoiding optical noise aroused by the processing of a wavelength division multiplexing device, improving the accuracy of the analyzer measuring concentrations and reducing the cost.

Description

technical field [0001] The invention relates to a laser gas analyzer, in particular to a laser gas analyzer for multi-component multiplexing measurement. Background technique [0002] Semiconductor laser gas analyzer is a "real-time" and "on-line" gas monitoring device, which is often used in petrochemical, steel, cement, environmental protection, industrial online monitoring and other fields. Laser gas analyzer is a high-sensitivity gas analysis method. Its principle is that after the laser of a specific wavelength passes through the gas, it is absorbed by the specific absorption peak of the gas, resulting in attenuation of light intensity. The attenuation of light intensity can be accurately described by the Beer-Lambert law: [0003] [0004] in are the light intensity after the laser passes through the gas and before passing through the gas, v is the frequency of the laser, P, X and L are the pressure, concentration and optical path of the gas, respectively. L...

AI Technical Summary

Problems solved by technology

At the same time, due to the large volume of large boilers, a single detection point cannot effectively reflect the overall concentration of the boiler, so it is necessary to measure the concentration of various characteristic gases at multiple measurement points

However, an ordinary laser gas analyzer can only measure the concentration of one characteristic gas per instrument. If the concentration of multiple characteristic gases is measured at multiple locations on site, many analyzers must be arranged, and the on-site installation will be very complicated and confusing.

Even in some positions, it is impossible to provide so many welding flange openings, and it is impossible to measure the characteristic gas concentration

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