Full-laser methane and carbon monoxide detection device and method for borehole extraction

Abstract

The invention discloses a full-laser methane and carbon monoxide detection device for borehole extraction. The full-laser methane and carbon monoxide detection device comprises a connecting pipe, a gas buffer pool communicated with one end of the connecting pipe, a methane sensor assembly, a carbon monoxide sensor assembly, a control processing module, a transmission module and a power supply module, the methane sensor assembly and the carbon monoxide sensor assembly are fixedly arranged side by side at the top of the gas buffer pool with the cavity structure and are provided with gas to be detected by the gas buffer pool through the gas exchange membrane; the control processing module is connected with the methane sensor assembly, the carbon monoxide sensor assembly, the transmission module and the power supply module; the invention further discloses a corresponding detection method. Photoacoustic signals can be accurately picked up in an underground complex sound field environment, and full-range detection of methane concentration and high-precision detection of trace carbon monoxide are realized; and the system complexity is reduced, and the device size is reduced.

Description

Technical Field

[0001] The invention relates to the field of gas detection, and in particular to a full-laser methane and carbon monoxide detection device and method for drilling extraction. Background Art

[0002] Borehole extraction is an effective measure to prevent gas-powered disasters. The main component of gas is methane, which also contains a small amount of ethane, propane and other gases. In addition, borehole negative pressure extraction is prone to cause spontaneous combustion of coal, and the process is accompanied by the production of carbon monoxide. According to statistics, the main causes of underground fires, explosions, poisoning, suffocation and other accidents are mostly methane and carbon monoxide. In order to ensure safe and efficient mining, it is necessary to detect methane and carbon monoxide gases in the borehole extraction pipeline.

[0003] With the intelligent development of the coal mining industry and the increase in mining depth, coal mining companies attach great importance to underground safety, and the demand for borehole extraction gas detection is increasing. However, there are still many shortcomings in the existing borehole extraction gas detection equipment. First of all, traditional gas detection equipment is large in size, occupies a lot of space, is difficult to maintain, and has high power consumption. It is extremely inconvenient to install and arrange these devices in areas with limited space such as narrow tunnels in coal mines. Secondly, infrared absorption spectroscopy sensors are mostly used for full-range detection of methane, and trace gases cannot be measured within the limited gas pool volume. Therefore, sensors for detecting trace carbon monoxide gas in boreholes are mostly based on electrochemical, catalytic combustion and other principles, and their sensitivity and accuracy are insufficient.

[0004] Continuous technological innovation has led to significant progress in laser technology and weak signal detection technology. Photoacoustic spectroscopy is based on the photoacoustic effect and detects the gas concentration by detecting the acoustic signal. However, the complex gas environment and strong noise interference in the well make this method difficult to apply. Other solutions have the problem of large size and inconvenient installation in the well. Summary of the invention

[0005] In view of the problems or defects in the prior art, the object is to provide an accurate and reliable online detection device for the methane and carbon monoxide gas concentration in borehole extraction gas, which can solve the problems of low accuracy and large size of the existing gas detection technology in the well.

[0006] The scheme of the present invention is as follows: a full laser methane and carbon monoxide detection device for drilling extraction, comprising: a connecting pipe, a gas buffer tank connected to one end of the connecting pipe, a methane sensor assembly, a carbon monoxide sensor assembly, a control processing module, and a transmission module including a wireless transmission module, a wired transmission module and a power supply module; the methane sensor assembly and the carbon monoxide sensor assembly are fixedly arranged side by side on the top of the gas buffer tank of the cavity structure and the gas buffer tank provides the gas to be detected to the two through a gas exchange membrane; the control processing module is connected to the methane sensor assembly, the carbon monoxide sensor assembly, the transmission module, and the power supply module;

[0007] The methane sensor assembly includes a gas cell body with a cavity structure; a MEMS infrared light source and an infrared detector are respectively embedded at the center of the cavity wall on the left and right sides of the gas cell body, with their centers at the same height; the carbon monoxide sensor assembly includes a photoacoustic cell body with a cavity structure; a first MEMS microphone is embedded at the center of the top of the photoacoustic cell body, and a second MEMS microphone is embedded at the center of the rear side; the first MEMS microphone and the second MEMS microphone form a spatial array; the gas exchange membrane at the connection between the photoacoustic cell body and the gas buffer cell is staggered at a distance from the first MEMS microphone in the horizontal direction to reduce the influence of gas flow on the MEMS microphone receiving the photoacoustic signal; a MEMS infrared laser is embedded at the center of the right side of the photoacoustic cell body; the sinusoidal modulation signal frequencies of the EMS infrared light source and the MEMS infrared laser are consistent.

[0008] It also includes a display module and an explosion-proof housing connected to the control processing module; the gas buffer tank, methane sensor, carbon monoxide sensor, control processing module, transmission module, and power supply module are all arranged in the explosion-proof housing;

[0009] Furthermore, the MEMS infrared laser, the first MEMS microphone, the second MEMS microphone, the MEMS infrared light source, and the infrared detector are all provided with interface circuits at their tail ends, and relevant pins are connected to the control processing module.

[0010] Furthermore, a high reflectivity window is fixed at the center of the left side of the photoacoustic cell body through a cover plate to increase the optical path and improve the detection sensitivity. The high reflectivity window and the center of the MEMS infrared laser are at the same level.

[0011] Furthermore, a first through channel structure is provided at the connection between the gas pool body and the gas buffer pool; a first gas exchange membrane is provided in the first through channel structure, and the gas in the gas buffer pool can enter the gas pool through the first gas exchange membrane; a second through channel structure is provided at the connection between the photoacoustic pool body and the gas buffer pool, a second gas exchange membrane is provided in the second through channel structure, and the gas in the gas buffer pool can enter the photoacoustic pool through the second gas exchange membrane; the gas exchange membrane further prevents coal dust from entering on the one hand, and reduces the noise of gas exchange on the other hand.

[0012] Furthermore, it also includes a water-dust filter arranged on the connecting pipe, including a water filter and a dust filter.

[0013] Furthermore, the bottom of the gas buffer pool has a central opening which is connected to the connecting pipe; the bottom of the gas buffer pool cavity is inclined downward toward the central opening to prevent dust from accumulating in the gas buffer pool.

[0014] Furthermore, the control processing module includes a laser control circuit, a photoacoustic signal preprocessing circuit, a phase-locked amplifier circuit and a central processing circuit; the laser control circuit includes a laser modulation circuit and a laser temperature control circuit;

[0015] The laser modulation circuit can generate a sinusoidal modulation signal and a sawtooth wave signal or a triangle wave signal to modulate the MEMS infrared light source and the MEMS infrared laser;

[0016] The laser temperature control circuit respectively regulates the temperature of the MEMS infrared light source and the MEMS infrared laser;

[0017] The photoacoustic signal preprocessing circuit performs delay processing on the photoacoustic signal received by the second MEMS microphone, and then performs addition and subtraction, time-frequency decomposition and other operations on the photoacoustic signal received by the first MEMS microphone to obtain the target photoacoustic signal, so as to further reduce the strong noise interference of the underground environment and the noise interference of the photoacoustic pool, and improve the detection limit of trace carbon monoxide;

[0018] The phase-locked amplifier circuit receives the signal from the infrared detector and the photoacoustic signal processed by the photoacoustic signal preprocessing circuit, locks and amplifies the second harmonic f signal;

[0019] The central processing circuit is used to collect and process the second harmonic signal, and store and transmit the gas concentration result obtained by the processing.

[0020] Furthermore, the frequency of the sinusoidal modulation signal is designed according to the resonance frequency of the photoacoustic cell, because the sinusoidal modulation signal frequency has a greater impact on the carbon monoxide sensor based on the principle of photoacoustic spectroscopy, but has a smaller impact on the methane sensor based on the principle of absorption spectroscopy. Therefore, in the laser modulation circuit of this embodiment, a DDS chip can be used to generate a sinusoidal modulation signal.

[0021] Furthermore, the wavelength of the laser emitted by the MEMS infrared laser includes but is not limited to 1567nm and 4.67μm, which is used to excite carbon monoxide gas to produce photoacoustic signals; the MEMS infrared light source, whose wavelength includes but is not limited to 1653nm and 3.4μm, is used to excite methane gas.

[0022] As another aspect of the present invention, it also relates to a full laser methane and carbon monoxide detection method for borehole extraction, comprising the following steps:

[0023] Step 1: Preparation

[0024] Ensure that all components, including connecting pipes, water and dust filters, gas buffer tanks, methane sensors, carbon monoxide sensors, control processing modules, display modules, wireless transmission modules, wired transmission modules and power supply modules, are properly installed and connected; provide power to the device through the power supply module to ensure normal startup of the device; calibrate the methane sensor and carbon monoxide sensor as needed to ensure detection accuracy;

[0025] Step 2: Connect the extraction pipeline

[0026] Connecting pipeline: Connect one end of the connecting pipe to the extraction pipeline in the coal mine, ensuring the connection is tight and leak-free;

[0027] Check the sealing: confirm that the connection pipe joints are well sealed to prevent gas leakage from affecting the test results;

[0028] Step 3: Start the detection device

[0029] Turn on the power of the equipment and start the laser control circuit and photoacoustic signal preprocessing circuit in the control processing module; perform initial settings through the display module, including detection parameters and transmission methods;

[0030] Step 4: Gas extraction and filtration

[0031] The underground gas is transported to the detection device through the extraction pipeline; the gas first passes through the water and dust filter to remove moisture and impurities to prevent damage to the sensor;

[0032] Step 5: Gas Detection

[0033] Methane detection:

[0034] The gas enters the methane sensor through the gas buffer cell;

[0035] The MEMS infrared light source excites the methane gas, and the infrared detector detects the generated spectral signal;

[0036] The control processing module processes the signal and calculates the methane concentration;

[0037] Carbon Monoxide Detection:

[0038] The gas enters the carbon monoxide sensor through the gas buffer cell;

[0039] The MEMS infrared laser excites carbon monoxide gas to generate a photoacoustic signal;

[0040] The first MEMS microphone and the second MEMS microphone receive the photoacoustic signal, and the control processing module processes the signal to calculate the carbon monoxide concentration;

[0041] Step 6: Data processing and display

[0042] The central processing circuit of the control processing module collects and processes the signals from the methane sensor and the carbon monoxide sensor, and calculates the gas concentration; the processing results are displayed through the display module, including the real-time concentrations of methane and carbon monoxide.

[0043] The beneficial effects and features of the present invention are:

[0044] (1) The full-laser methane and carbon monoxide detection device for borehole extraction of the present invention adopts absorption spectroscopy technology and its derived photoacoustic spectroscopy method to detect the concentrations of methane and carbon monoxide in borehole extracted gas, realizes full-range detection of methane concentration and high-precision detection of trace carbon monoxide, can solve the problem of accurate detection of trace carbon monoxide in borehole extraction, provide reliable data for coal spontaneous combustion early warning, and has the advantages of high gas selectivity, high stability, fast response speed, and adaptability to complex environments.

[0045] (2) The full laser methane and carbon monoxide detection device for drilling extraction of the present invention has a carbon monoxide sensor with a thick photoacoustic cell body, which can achieve shock resistance and noise isolation, and uses a dual-microphone spatial array to further reduce noise, and can accurately pick up photoacoustic signals in a complex acoustic field environment underground.

[0046] (3) The full laser methane and carbon monoxide detection device for borehole extraction of the present invention has a sinusoidal modulation signal frequency that drives the methane sensor light source and the carbon monoxide sensor light source, unifies and simplifies the dual-light source laser modulation circuit and phase-locked amplifier circuit in sensors with different spectral principles, and helps to reduce system complexity and device size. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 This is a schematic diagram of a full-laser methane and carbon monoxide detection device for drilling extraction according to a preferred embodiment of the present invention.

[0048] Figure 2 This is a schematic diagram of the structure and connection method of the gas buffer tank, methane sensor, and carbon monoxide sensor in a preferred embodiment of the present invention.

[0049] Figure 3 Schematic diagram of the circuit principle of the control processing module of a preferred embodiment of the present invention.

[0050] The reference numerals in the figure represent respectively: 1-connecting pipe, 2-water and dust filter, 3-gas buffer tank, 4-methane sensor, 4-1-first gas exchange membrane, 4-2-MEMS infrared light source, 4-3-infrared detector, 4-4-gas tank body, 4-5-gas tank, 5-monoxide detection sensor, 5-1-second gas exchange membrane, 5-2-MEMS infrared laser, 5-3-high reflectivity window, 5-4-cover plate, 5-5-first MEMS microphone, 5-6-second MEM S microphone, 5-7-photoacoustic cell body, 5-8-photoacoustic cell, 6-control processing module, 6-1-laser control circuit, 6-1-1-laser modulation circuit, 6-1-2-laser temperature control circuit, 6-2-photoacoustic signal preprocessing circuit, 6-3-phase-locked amplifier circuit, 6-4-central processing circuit, 7-display module, 8-wireless transmission module, 9-wired transmission module, 10-power supply module, 11-explosion-proof housing, 12-first through channel structure, 13-second through channel structure. DETAILED DESCRIPTION

[0051] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0052] Please refer to Figure 1 An embodiment of the present invention relates to a full-laser methane and carbon monoxide detection device for drilling extraction, including a connecting pipe 1, a water and dust filter 2, and a gas buffer tank 3, a methane sensor 4, a carbon monoxide sensor 5, a control processing module 6, a display module 7, a wireless transmission module 8, a wired transmission module 9 and a power supply module 10 installed in an explosion-proof housing 11.

[0053] One end of the connecting pipe 1 is connected to the extraction pipeline, and the connection method includes but is not limited to connecting to the gas extraction valve, inserting a single hole into the pipeline, etc. The other end of the connecting pipe 1 is connected to the water dust filter 2.

[0054] The bottom center of the gas buffer pool 3 is opened and connected to the water dust filter 2. The bottom of the gas buffer pool 3 has a certain inclination toward the center to prevent dust from accumulating in the gas buffer pool 3.

[0055] The power supply module 10 is connected to the control processing module 6 and is powered by an intrinsically safe battery.

[0056] Please refer to Figure 2 Two internal threaded holes are provided on the top of the gas buffer pool 3, which are respectively fastened to the external threaded columns at the bottom of the gas pool body 4-4 and the photoacoustic pool body 5-7.

[0057] As a preferred solution, the gas pool body 4-4 is bonded with a first gas exchange membrane 4-1 at the threaded connection to facilitate gas inflow and outflow.

[0058] As a preferred solution, the material of the gas pool body 4-4 is metal, including but not limited to brass and stainless steel.

[0059] As a preferred solution, a MEMS infrared light source 4-2 is embedded in the center of the left side of the gas pool body 4-4, and its wavelength includes but is not limited to 1653nm and 3.4μm, which is used to excite methane gas. An infrared detector 4-3 is embedded in the center of the right side of the gas pool body 4-4. The centers of the MEMS infrared light source 4-2 and the infrared detector 4-3 are at the same horizontal height. The tail ends of the MEMS infrared light source 4-2 and the infrared detector 4-3 are both provided with interface circuits, and the relevant pins are connected to the control processing module 6.

[0060] As a preferred solution, a cylindrical gas pool 4-5 is formed in the center of the gas pool body 4-4. As another embodiment, a reflector or a concave mirror can also be added to the gas pool 4-5 to increase the optical path.

[0061] As a preferred solution, a second gas exchange membrane 5-1 is bonded to the threaded hole connection of the photoacoustic cell body 5-7 to facilitate gas entry and exit; the photoacoustic cell body 5-7 is made of metal, including but not limited to brass and stainless steel, and the cell body is thick enough to achieve the effect of shock absorption and isolation of external noise.

[0062] A MEMS infrared laser 5-2 is embedded in the center of the right side of the photoacoustic cell body 5-7, and its wavelength includes but is not limited to 1567nm and 4.67μm, which is used to excite carbon monoxide gas to generate photoacoustic signals; a high reflectivity window 5-3 is fixed to the center of the left side of the photoacoustic cell body 5-7 through a cover plate 5-4 to increase the optical path and improve the detection sensitivity. The center of the high reflectivity window 5-3 and the MEMS infrared laser 5-2 are at the same level.

[0063] Those skilled in the art should understand that Figure 2 The high reflectivity window shown is only an example. In some other embodiments, the high reflectivity window and the cover plate may be removed, leaving the complete cell body on the left.

[0064] Furthermore, a first MEMS microphone 5-5 is embedded in the center of the top of the photoacoustic cell body 5-7, and a second MEMS microphone 5-6 is embedded in the center of the rear side. The first MEMS microphone 5-5 and the second MEMS microphone 5-6 form a spatial array. The second gas exchange membrane 5-1 is not on the same vertical line as the first MEMS microphone 5-5 to prevent the gas inlet and outlet noise from affecting the photoacoustic spectrum detection effect, so as to reduce the impact of gas flow on the MEMS microphone 5-5 receiving the photoacoustic signal. The MEMS infrared laser 5-2, the first MEMS microphone 5-5 and the second MEMS microphone 5-6 have interface circuits at their tail ends, and the relevant pins are connected to the control processing module 6.

[0065] As a preferred solution, a cylindrical photoacoustic cell 5-8 is formed in the center of the photoacoustic cell body 5-7, and its surface is smooth and can be plated with gold or silver when necessary.

[0066] Those skilled in the art should understand that Figure 2 The cylindrical photoacoustic cell shown is only an example, and the actual photoacoustic cell structure may also be a spherical type, a Helmholtz resonant cavity, etc.

[0067] Please refer to Figure 3 The control processing module 6 mainly includes a laser control circuit 6-1, a photoacoustic signal preprocessing circuit 6-2, a phase-locked amplifier circuit 6-3, and a central processing circuit 6-4. Among them, the laser control circuit 6-1 includes a laser modulation circuit 6-1-1 and a laser temperature control circuit 6-1-2; the laser modulation circuit 6-1-1 can generate a sine modulation signal and a sawtooth wave signal or a triangle wave signal to modulate the MEMS infrared light source 4-2 and the MEMS infrared laser 5-2.

[0068] Furthermore, the sinusoidal modulation signal frequency f is designed according to the resonance frequency of the photoacoustic cell 5-8, because the sinusoidal modulation signal frequency has a greater impact on the carbon monoxide sensor based on the photoacoustic spectroscopy principle, but has a smaller impact on the methane sensor based on the absorption spectroscopy principle. Therefore, in the laser modulation circuit of this embodiment, a DDS chip can be used to generate a sinusoidal modulation signal.

[0069] The laser temperature control circuit 6-1-2 regulates the temperature of the MEMS infrared light source 4-2 and the MEMS infrared laser 5-2 respectively.

[0070] The photoacoustic signal preprocessing circuit 6-2 performs delay processing on the photoacoustic signal received by the second MEMS microphone 5-6, and then performs addition, subtraction, time-frequency decomposition and other operations on the photoacoustic signal received by the first MEMS microphone 5-5 to obtain the target photoacoustic signal, so as to further reduce the strong noise interference of the underground environment and the noise interference of the photoacoustic pool, and improve the detection limit of trace carbon monoxide.

[0071] The phase-locked amplifier circuit 6-3 receives the signal from the infrared detector 4-3 and the photoacoustic signal processed by the photoacoustic signal preprocessing circuit 6-2, and locks and amplifies its second harmonic (2f) signal.

[0072] The central processing circuit 6 - 4 is used to collect and process the second harmonic signal, and store and transmit the processed gas concentration results.

[0073] Please refer to Figure 1 As a preferred solution, the control processing module 6 is also connected to the display module 7, the wireless transmission module 8 and the wired transmission module 9 for displaying and transmitting the methane and carbon monoxide concentration detection results.

[0074] Among them, the communication methods of the wireless transmission module 8 include but are not limited to WiFi, LORA, etc., and the gas concentration detection results can be uploaded to the upper-level equipment, such as the underground signal acquisition substation and the surface monitoring platform. The specific implementation method is set according to the mine environment and surface requirements.

[0075] Among them, the communication methods of the wired transmission module 9 include but are not limited to RS485, optical cable, etc., and the gas concentration detection results can be uploaded to the upper-level equipment, such as the underground signal acquisition substation and the surface monitoring platform. The specific implementation method is set according to the mine environment and surface requirements.

[0076] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A full laser methane and carbon monoxide detection device for drilling extraction, characterized in that: include: A connecting pipe (1), a gas buffer pool (3) connected to one end of the connecting pipe, a methane sensor assembly (4), a carbon monoxide sensor assembly (5), a control processing module (6), a transmission module and a power supply module (10); the methane sensor assembly (4) and the carbon monoxide sensor assembly (5) are fixedly arranged side by side on the top of the gas buffer pool (3) with a cavity structure, and the gas buffer pool provides the gas to be detected to the two through a gas exchange membrane; the control processing module (6) is connected to the methane sensor assembly (4), the carbon monoxide sensor assembly (5), the transmission module and the power supply module (10); The methane sensor assembly (4) comprises a gas cell body (4-4) with a cavity structure; a MEMS infrared light source (4-2) and an infrared detector (4-3) are respectively embedded at the center of the cavity wall on the left and right sides of the gas cell body (4-4) with their centers at the same height; the carbon monoxide sensor assembly (5) comprises a photoacoustic cell body (5-7) with a cavity structure; a first MEMS microphone (5-5) is embedded at the center of the top of the photoacoustic cell body (5-7), and a second MEMS microphone (5-6) is embedded at the center of the rear side; the first MEMS microphone (5-5) and the second MEMS microphone (5-6) form a spatial array; a gas exchange membrane (5-1) at the connection between the photoacoustic cell body (5-7) and the gas buffer cell (3) is staggered with the first MEMS microphone (5-5) in the horizontal direction; a MEMS infrared laser (5-2) is embedded at the center of the right side of the photoacoustic cell body (5-7); and the sinusoidal modulation signal frequencies of the EMS infrared light source (4-2) and the MEMS infrared laser (5-2) are consistent.

2. The full laser methane and carbon monoxide detection device for drilling extraction according to claim 1 is characterized in that: The MEMS infrared laser (5-2), the first MEMS microphone (5-5), the second MEMS microphone (5-6), the MEMS infrared light source (4-2), and the infrared detector (4-3) all have interface circuits at their tail ends, and related pins are connected to a control processing module (6).

3. The full laser methane and carbon monoxide detection device for drilling extraction according to claim 1 is characterized in that: A high reflectivity window (5-3) is fixed to the left center of the photoacoustic cell body (5-7) through a cover plate (5-4) to increase the optical path and improve the detection sensitivity; the high reflectivity window (5-3) and the center of the MEMS infrared laser (5-2) are at the same level.

4. The full laser methane and carbon monoxide detection device for drilling extraction according to claim 1 is characterized in that: A first through-channel structure (12) is provided at the connection between the gas pool body (4-4) and the gas buffer pool (3); a first gas exchange membrane (4-1) is provided in the first through-channel structure (12), and the gas in the gas buffer pool (3) can enter the gas pool (4-5) through the first gas exchange membrane (4-1); a second through-channel structure (13) is provided at the connection between the photoacoustic pool body (5-7) and the gas buffer pool (3), a second gas exchange membrane (5-1) is provided in the second through-channel structure (13), and the gas in the gas buffer pool (3) can enter the photoacoustic pool (5-8) through the second gas exchange membrane (5-1).

5. The full laser methane and carbon monoxide detection device for drilling extraction according to claim 1 is characterized in that: It also includes a water and dust filter (2) arranged on the connecting pipe (1).

6. The full laser methane and carbon monoxide detection device for drilling extraction according to claim 1 is characterized in that: The gas buffer pool (3) has a central opening at the bottom thereof, which is connected to the connecting pipe (1); the bottom of the cavity of the gas buffer pool (3) is inclined downward toward the central opening.

7. The full laser methane and carbon monoxide detection device for drilling extraction according to any one of claims 1 to 6, characterized in that: The control processing module (6) comprises a laser control circuit (6-1), a photoacoustic signal preprocessing circuit (6-2), a phase-locked amplifier circuit (6-3) and a central processing circuit (6-4); the laser control circuit (6-1) comprises a laser modulation circuit (6-1-1) and a laser temperature control circuit (6-1-2); The laser modulation circuit (6-1-1) can generate a sinusoidal modulation signal and a sawtooth wave signal or a triangle wave signal to modulate the MEMS infrared light source (4-2) and the MEMS infrared laser (5-2); The laser temperature control circuit (6-1-2) respectively regulates the temperature of the MEMS infrared light source (4-2) and the MEMS infrared laser (5-2); The photoacoustic signal preprocessing circuit (6-2) performs delay processing on the photoacoustic signal received by the second MEMS microphone 5-6), and then performs addition, subtraction, time-frequency decomposition and other operations on the photoacoustic signal received by the first MEMS microphone (5-5) to obtain a target photoacoustic signal; The phase-locked amplifier circuit (6-3) receives the signal from the infrared detector (4-3) and the photoacoustic signal processed by the photoacoustic signal preprocessing circuit (6-2), and locks and amplifies the second harmonic signal thereof; The central processing circuit (6-4) is used to collect and process the second harmonic signal, and store and transmit the gas concentration results obtained through the processing.

8. The full laser methane and carbon monoxide detection device for drilling extraction according to claim 7 is characterized in that: The frequency of the sinusoidal modulation signal is designed according to the resonance frequency of the photoacoustic cell (5-8). This is because the frequency of the sinusoidal modulation signal has a greater impact on the carbon monoxide sensor based on the principle of photoacoustic spectroscopy, but has a smaller impact on the methane sensor based on the principle of absorption spectroscopy; therefore, a DDS chip is used in the laser modulation circuit to generate a sinusoidal modulation signal.

9. The full laser methane and carbon monoxide detection device for drilling extraction according to claim 7, characterized in that: The MEMS infrared laser (5-2) emits laser wavelengths including but not limited to 1567nm and 4.67μm, which is used to excite carbon monoxide gas to generate photoacoustic signals; the MEMS infrared light source (4-2) has a wavelength including but not limited to 1653nm and 3.4μm.

10. The detection method of the full laser methane and carbon monoxide detection device for borehole extraction according to any one of claims 1 to 6, characterized in that: The steps include: Step 1: Preparation Ensure that all components, including the connecting pipe (1), the water and dust filter (2), the gas buffer tank (3), the methane sensor (4), the carbon monoxide sensor (5), the control processing module (6), the display module (7), the wireless transmission module (8), the wired transmission module (9) and the power supply module (10), are properly installed and connected; provide power to the device through the power supply module (10) to ensure that the device starts normally; calibrate the methane sensor (4) and the carbon monoxide sensor (5) as needed to ensure detection accuracy; Step 2: Connect the extraction pipeline Connecting pipeline: connect one end of the connecting pipe (1) to the extraction pipeline in the coal mine, ensuring that the connection is tight and leak-free; Check the sealing: make sure that the connection of the connecting pipe (1) is well sealed to prevent gas leakage from affecting the test results; Step 3: Start the detection device Turn on the power of the device, start the laser control circuit and the photoacoustic signal preprocessing circuit in the control processing module (6); perform initial settings through the display module (7), including detection parameters and transmission mode; Step 4: Gas extraction and filtration The underground gas is transported to the detection device through the extraction pipeline; the gas first passes through the water and dust filter (2) to remove moisture and impurities to prevent damage to the sensor; Step 5: Gas Detection Methane detection: gas enters the methane sensor (4) through the gas buffer pool (3); the MEMS infrared light source (4-2) excites the methane gas, and the infrared detector (4-3) detects the generated spectral signal; the control processing module (6) processes the signal and calculates the methane concentration; Carbon monoxide detection: gas enters the carbon monoxide sensor (5) through the gas buffer pool (3); the MEMS infrared laser (5-2) excites the carbon monoxide gas to generate a photoacoustic signal; the first MEMS microphone (5-5) and the second MEMS microphone (5-6) receive the photoacoustic signal, and the control processing module (6) processes the signal to calculate the carbon monoxide concentration; Step 6: Data processing and display The central processing circuit of the control processing module (6) collects and processes the signals from the methane sensor (4) and the carbon monoxide sensor (5) to calculate the gas concentration; the processing results are displayed through the display module (7), including the real-time concentrations of methane and carbon monoxide.

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