A gas concentration detection system and method in a liquid

Abstract

This invention relates to a gas concentration detection system in a liquid, comprising a storage tank, a multi-wavelength laser, a fiber laser hydrophone, and a mobile device. The storage tank has a resonant cavity for containing a liquid sample. The multi-wavelength laser is positioned opposite the incident end of the storage tank and emits a laser beam into the storage tank, enabling the gas in the liquid sample to absorb the laser and generate an acoustic signal. The fiber laser hydrophone is located within the resonant cavity and is used to collect the acoustic signal and convert it into an optical signal. The mobile device is communicatively connected to the fiber laser hydrophone and is used to calculate the concentration of the gas being measured based on the optical signal. This invention, through the combined use of the multi-wavelength laser, fiber laser hydrophone, and mobile device, eliminates the need for degassing the liquid sample and allows for direct measurement of the gas concentration in the liquid sample.

Description

Technical Field

[0001] This invention relates to the field of gas detection technology, and more specifically to a gas concentration detection system and method in a liquid. Background Technology

[0002] Currently, gas detection is mainly based on photoacoustic spectroscopy. However, photoacoustic spectroscopy requires degassing of the liquid before gas concentration detection can be performed. However, due to the large dispersion during gas-liquid separation and degassing, the detection results are highly variable. Furthermore, the time-consuming degassing process significantly limits the real-time performance of online detection. Summary of the Invention

[0003] Based on the above description, the present invention provides a gas concentration detection system and method in liquids, aiming to solve the problems of long degassing time and large degassing dispersion in existing gas detection methods in liquids, which leads to large dispersion of detection results.

[0004] The technical solution of the present invention to solve the above-mentioned technical problems is as follows:

[0005] In a first aspect, a gas concentration detection system in a liquid includes:

[0006] A liquid storage tank having a resonant cavity for containing a liquid sample;

[0007] A multi-wavelength laser is disposed opposite to the incident end of the liquid storage tank. The multi-wavelength laser is used to emit a laser beam into the liquid storage tank, which enables the gas in the liquid sample to absorb the laser and generate an acoustic signal.

[0008] A fiber laser hydrophone is disposed within the resonant cavity. The fiber laser hydrophone is used to collect the acoustic wave signal and convert it into an optical signal.

[0009] A mobile device is communicatively connected to the fiber laser hydrophone, and the mobile device is used to calculate the concentration of the gas being measured based on the optical signal.

[0010] Based on the above technical solution, the present invention can be further improved as follows.

[0011] Furthermore, the resonant cavity is constructed in a horn shape.

[0012] Furthermore, it includes a spatial light modulator, which is disposed between the multi-wavelength laser and the incident end of the liquid storage tank, and the spatial light modulator is used to modulate the laser beam.

[0013] Furthermore, it includes a laser controller electrically connected to the multi-wavelength laser, the laser controller being used to control the multi-wavelength laser to emit laser beams of different wavelengths.

[0014] Furthermore, it includes a conductivity sensor, the detection end of which penetrates the bottom wall of the liquid storage tank and is inserted into the resonant cavity. The conductivity sensor is electrically connected to the mobile device and is used to detect the conductivity of the liquid sample.

[0015] Furthermore, it includes a spectrometer, which is disposed opposite to the emission end of the liquid storage tank. The spectrometer is electrically connected to the mobile device. The spectrometer is used to receive the laser beam emitted from the liquid storage tank to generate a spectral image, and to calculate the impurity content of the liquid sample based on the spectral image.

[0016] In a second aspect, a method for detecting gas concentration in a liquid, the gas detection method being applicable to the gas concentration detection system in a liquid described in the first aspect, comprising:

[0017] The multi-wavelength laser emits a laser beam toward the liquid storage tank, which enables the gas in the liquid sample to absorb the laser and generate an acoustic signal.

[0018] The fiber laser hydrophone collects the acoustic signal and converts it into an optical signal;

[0019] The mobile device calculates the concentration of the gas being measured based on the optical signal.

[0020] Compared with the prior art, the technical solution of the present invention has the following beneficial technical effects:

[0021] (1) The present invention uses a multi-wavelength laser, a fiber laser hydrophone and a mobile device to directly measure the gas concentration of the liquid sample without the need for degassing.

[0022] (2) The curved liquid storage tank wall in the horn-shaped resonant cavity of the present invention can improve the resonance of the acoustic signal, while maximizing the reduction of the noise when the laser beam passes through the liquid storage tank, and further improving the detection accuracy of the gas components to be measured in the liquid sample. Attached Figure Description

[0023] Figure 1 This is a structural block diagram of a gas concentration detection system in a liquid provided in an embodiment of the present invention;

[0024] Figure 2 This is a comparison diagram of the acoustic wave signal test results of the horn-shaped resonant cavity and the I-shaped resonant cavity in an embodiment of the present invention;

[0025] Figure 3 This is a comparison chart of the concentration test results of four transformer oils containing different concentrations of acetylene in embodiments of the present invention.

[0026] Explanation of reference numerals in the attached figures:

[0027] 1. Liquid storage tank; 11. Resonant cavity;

[0028] 2. Multi-wavelength laser;

[0029] 3. Fiber laser hydrophone;

[0030] 4. Mobile devices;

[0031] 5. Spatial light modulator;

[0032] 6. Laser controller;

[0033] 7. Conductivity sensor;

[0034] 8. Spectrometer. Detailed Implementation

[0035] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Embodiments of the invention are shown in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of the invention will be thorough and complete.

[0036] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0037] It is understood that spatial relation terms such as "below," "under," "below," "below," "above," "over," etc., can be used here to describe the relationship between one element or feature shown in the figure and other elements or features. It should be understood that, in addition to the orientation shown in the figure, spatial relation terms also include different orientations of the device in use and operation. For example, if the device in the figure is flipped, the element or feature described as "below" or "under" or "below" of other elements or features will be oriented "over" of other elements or features. Therefore, the exemplary terms "below" and "under" can include both upper and lower orientations. Furthermore, the device may also include other orientations (e.g., rotated 90 degrees or other orientations), and the spatial descriptive terms used herein will be interpreted accordingly.

[0038] When used herein, the singular forms of “a,” “an,” and “the” may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising,” “including,” or “having,” etc., specify the presence of the stated feature, whole, step, operation, component, part, or combination thereof, but do not preclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof.

[0039] Reference Figure 1 As shown, the present invention provides a technical solution: a gas concentration detection system in a liquid, comprising a storage tank 1, a multi-wavelength laser 2, a fiber laser hydrophone 3, and a mobile device 4; the storage tank 1 has a resonant cavity 11 for containing a liquid sample; the multi-wavelength laser 2 is disposed opposite to the incident end of the storage tank 1, and the multi-wavelength laser 2 is used to emit a laser beam into the storage tank 1, which enables the gas in the liquid sample to absorb the laser and generate an acoustic signal; the fiber laser hydrophone 3 is disposed inside the resonant cavity 11, and the fiber laser hydrophone 3 is used to collect the acoustic signal and convert it into an optical signal; the mobile device 4 is communicatively connected to the fiber laser hydrophone 3, and the mobile device 4 is used to calculate the concentration of the gas to be measured based on the optical signal.

[0040] For example, mobile device 4 can be a computer, etc.

[0041] In this embodiment, by using a multi-wavelength laser 2, a fiber laser hydrophone 3, and a mobile device 4, the gas concentration of the liquid sample can be directly measured without the need for degassing the liquid sample.

[0042] Reference Figure 1 As shown, in some embodiments, the resonant cavity 11 is configured as a horn shape.

[0043] In this embodiment, the resonance of the acoustic signal can be improved by the curved liquid storage tank wall in the resonant cavity 11, while minimizing the noise of the laser beam passing through the liquid storage tank, thereby further improving the detection accuracy of the gaseous components in the liquid sample.

[0044] Due to significant dispersion and light absorption effects in liquid samples, please refer to... Figure 2 As shown, in a conventional I-shaped resonant cavity 11, the acoustic signal is not significant due to dispersion and light absorption effects after a laser beam is incident. However, the horn-shaped resonant cavity 11 of this invention exhibits a strong acoustic signal despite the effects of dispersion and light absorption.

[0045] Reference Figure 1 As shown, in some embodiments, a spatial light modulator 5 is included, which is disposed between the incident end of the multi-wavelength laser 2 and the liquid storage tank 1. The spatial light modulator 5 is used to modulate the laser beam.

[0046] In this embodiment, when the laser beam enters the spatial light modulator 5, the spatial light modulator 5 modulates the laser beam to control the phase and amplitude of the laser beam in order to obtain a high-resolution laser beam.

[0047] Reference Figure 1 As shown, in some embodiments, a laser controller 6 is included, which is electrically connected to a multi-wavelength laser 2 and is used to control the multi-wavelength laser 2 to emit laser beams of different wavelengths.

[0048] In this embodiment, the multi-wavelength laser 2 is controlled by the laser controller 6 to emit laser beams of different wavelengths, thereby enabling the detection of the concentration of different gases.

[0049] Reference Figure 1 As shown, in some embodiments, a conductivity sensor 7 is included. The detection end of the conductivity sensor 7 penetrates the bottom wall of the liquid storage tank 1 and is inserted into the resonant cavity 11. The conductivity sensor 7 is electrically connected to the mobile device 4. The conductivity sensor 7 is used to detect the conductivity of the liquid sample.

[0050] In this embodiment, the conductivity sensor 7 is used to measure the current and voltage of the liquid sample to calculate the conductivity or resistivity. Finally, the conductivity parameters of the liquid sample are obtained through the mobile device 4, thereby enabling multifunctional detection.

[0051] Reference Figure 1 As shown, in some embodiments, a spectrometer 8 is included, which is arranged opposite to the emission end of the liquid storage tank 1. The spectrometer 8 is electrically connected to the mobile device 4. The spectrometer 8 is used to receive the laser beam emitted from the liquid storage tank 1 to generate a spectral image and calculate the impurity content of the liquid sample based on the spectral image.

[0052] In this embodiment, the use of spectrometer 8 to detect impurities in the liquid sample can help users understand the state of the liquid sample in a timely manner, prevent potential problems, and improve production efficiency and quality control.

[0053] This invention was used to test four types of transformer oil containing different concentrations of acetylene. The acetylene concentration in the oil increased from 25 ml / L to 100 ml / L. During the experiment, the ambient temperature was approximately 25°C, and the pressure in the storage tank was maintained at standard atmospheric pressure. The relationship between acetylene concentration and sound wave signal intensity is as follows: Figure 3 As shown, it is clear that the intensity of the sound wave signal gradually increases with the increase of acetylene concentration.

[0054] This invention provides a technical solution: a method for detecting gas concentration in a liquid, applicable to the aforementioned liquid gas concentration detection system, comprising the following steps:

[0055] S1, the multi-wavelength laser 2 emits a laser beam toward the liquid storage tank 1, which enables the gas in the liquid sample to absorb the laser and generate an acoustic signal.

[0056] S2, the fiber laser hydrophone 3 collects acoustic signals and converts them into optical signals;

[0057] S3, the mobile device 4 calculates the concentration of the gas being measured based on the optical signal.

[0058] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A gas concentration detecting system in a liquid, characterized by, include: The liquid storage tank (1) has a resonant cavity (11) which is constructed in a funnel shape, with the small end of the resonant cavity (11) facing the incident end of the liquid storage tank (1), and the resonant cavity (11) is used to contain liquid samples. A multi-wavelength laser (2) is disposed opposite to the incident end of the liquid storage tank (1). The multi-wavelength laser (2) is used to emit a laser beam into the liquid storage tank (1). Under the influence of dispersion effect and light absorption effect, the gas in the liquid sample can absorb the laser and generate a strong acoustic signal. A fiber laser hydrophone (3) is disposed inside the resonant cavity (11). The fiber laser hydrophone (3) is used to collect the acoustic signal and convert it into an optical signal. The mobile device (4) is communicatively connected to the fiber laser hydrophone (3), and the mobile device (4) is used to calculate the concentration of the gas to be measured based on the optical signal; Spatial light modulator (5), the spatial light modulator (5) is disposed between the multi-wavelength laser (2) and the incident end of the liquid storage tank (1), the spatial light modulator (5) is used to modulate the laser beam; A laser controller (6) is electrically connected to the multi-wavelength laser (2) and is used to control the multi-wavelength laser (2) to emit laser beams of different wavelengths. The conductivity sensor (7) has its detection end penetrating the bottom wall of the liquid storage tank (1) and inserted into the resonant cavity (11). The conductivity sensor (7) is electrically connected to the mobile device (4). The conductivity sensor (7) is used to detect the conductivity of the liquid sample. A spectrometer (8) is arranged opposite to the emission end of the liquid storage tank (1). The spectrometer (8) is electrically connected to the mobile device (4). The spectrometer (8) is used to receive the laser beam emitted from the liquid storage tank (1) to generate a spectral image and calculate the impurity content of the liquid sample based on the spectral image.

2. A method of detecting a gas in a liquid, characterized by, The gas detection method is applicable to a gas concentration detection system in a liquid according to claim 1, comprising: The multi-wavelength laser (2) emits a laser beam into the liquid storage tank (1). Under the influence of dispersion and light absorption effects, the gas in the liquid sample can absorb the laser and generate a strong acoustic signal. The fiber laser hydrophone (3) collects the acoustic signal and converts it into an optical signal; The mobile device (4) calculates the concentration of the gas being measured based on the optical signal.

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