Gas detection system and method

Abstract

According to the gas detection system and method provided by the invention, the signal receiving module can be prevented from being in direct contact with gas molecules and laser at the same time, the signal receiving module can be protected from being damaged by corrosive gas, and the thermal noise of the system can be reduced, so that the gas detection precision is ensured, and the signal-to-noise ratio of the system is improved. The system comprises a temperature control current source, a laser, a gas absorption cell, a hot wire type optical fiber and a signal receiving and demodulation module, the temperature control current source is connected with the laser device, an output end optical fiber of the laser device is connected with an input end of the gas absorption cell, an output end optical fiber of the gas absorption cell is connected with the hot-wire type optical fiber, the hot-wire type optical fiber is close to the signal receiving and demodulation module, the hot-wire type optical fiber can convert optical energy into heat energy, and the signal receiving and demodulation module is connected with the temperature control current source. And the signal receiving and demodulating module can detect the concentration of the gas to be detected in the gas absorption cell by utilizing the heat energy converted by the hot-wire type optical fiber.

Description

technical field [0001] The present application relates to the field of gas detection, in particular to a gas detection system and method. Background technique [0002] With the progress of society and the development of science and technology, high-precision monitoring of gas concentration is of great significance in many fields such as ensuring oil and gas exploitation, biopharmaceutical safety, air pollution prevention and control, food and drug safety, etc. The current common quartz-enhanced photoacoustic spectroscopy gas detection technology is a gas contact measurement technology. The quartz tuning fork is embedded in the gas sample to be measured, which limits its application in fields such as long-distance measurement, and if the gas to be measured As a corrosive gas, it will damage the metal film on the surface of the quartz tuning fork, resulting in frequency drift or even damage to the quartz tuning fork. [0003] At present, some scholars have proposed a quartz-e...

AI Technical Summary

Problems solved by technology

The current common quartz-enhanced photoacoustic spectroscopy gas detection technology is a gas contact measurement technology. The quartz tuning fork is embedded in the gas sample to be measured, which limits its application in fields such as long-distance measurement, and if the gas to be measured It is a corrosive gas that will damage the metal film on the surface of the quartz tuning fork, resulting in frequency drift or even damage to the quartz tuning fork

[0003] At present, some scholars have proposed a quartz-enhanced photothermal spectroscopy gas detection technology, which is a non-contact gas detection technology. After the light is absorbed in the gas absorption cell, it is directly incident on the quartz tuning fork arm. On the basis of photothermal effect, the gas is detected, but this method requires direct contact between the laser and the quartz tuning fork, which inevitably produces a lot of thermal noise, because the photothermal signal is proportional to the laser power, but the thermal noise of the quartz tuning fork and the laser The power is exponentially related, so the signal-to-noise ratio of the system will be greatly reduced

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