A high-density gas detection system and method applicable to an ultra-large-depth saturation living cabin

Abstract

The present invention discloses a high-density gas detection system applicable to an ultra-large depth saturation living cabin, which includes a high-pressure chamber, a sampling pipe, a gas treatment device, a first branch pipe, a second branch pipe, a third branch pipe, an EI source module, a PTR source module, a carbon monoxide detector, a mass spectrometry detection module, and gas detection software; the sampling pipe is connected to the first branch pipe, the second branch pipe, and the third branch pipe. The first branch pipe is used to direct the pretreated gas sample to the EI source module, the second branch pipe is used to direct the pretreated gas sample to the PTR source module, and the third branch pipe is used to direct the pretreated gas sample to the carbon monoxide detector; the mass spectrometry detection module is used to analyze the ionized gas obtained from the EI source module and the PTR source module; the gas detection software is used to process, display, and store the acquired detection data. The present invention selects appropriate detection modules according to the characteristics of different gases, achieving efficient and accurate detection of multiple gas components under high-pressure environments.

Description

Technical Field

[0001] This application belongs to the field of analytical detection, and particularly relates to a high-density gas detection system and method applicable to an ultra-large-depth saturation living cabin. Background Art

[0002] Ultra-large-depth saturation diving operations refer to long-duration diving work where divers are directly exposed to depths exceeding 120 meters underwater (even up to 300 - 500 meters). In such diving methods, divers first need to stay in a high-pressure environment cabin for a long time to adapt to the high-pressure environment at great depths underwater, and then directly enter and exit the large-depth underwater to carry out work, with a duration of up to 1 month. The gas environment in the ultra-large-depth saturation living cabin is more complex, and the presence of high-density gases increases the difficulty of detection. High-density gases such as CO2, NH3, N2, H2S, CH4, and other volatile organic compounds (VOCs) need to be accurately monitored to ensure that the gas composition in the cabin is within a safe range. Especially under high-pressure conditions, the concentration and distribution of these gases will change significantly, posing a potential threat to the health and safety of divers. Therefore, gas detection in the ultra-large-depth saturation living cabin not only needs to have high sensitivity and high precision but also needs to be able to respond in real time to the dynamic changes in gas composition.

[0003] In the prior art, there are many difficulties in detecting multiple high-density gases in a high-pressure cabin. First, the gas composition under high-pressure conditions is complex and the concentration changes greatly, requiring the detection system to have high sensitivity and high precision. Second, there may be interference between different gas components. For example, nitrogen and carbon monoxide have the same molecular weight (both are 28), making it difficult to distinguish them through traditional mass spectrometry techniques. In addition, water vapor has a great impact on the detection sensitivity of certain gases (such as H2S and NH3). Existing gas detection systems usually cannot simultaneously meet the detection requirements of high pressure, high humidity, and multiple gas components, and it is difficult to achieve real-time and accurate gas detection in a complex high-pressure environment. Summary of the Invention

[0004] Aiming at the deficiencies of the prior art, the present invention proposes a high-density gas detection system and method applicable to an ultra-large-depth saturation living cabin to solve the detection problems existing in the prior art and provide a more reliable and accurate gas detection means. When detecting gases such as CO2, O2, NH3, H2S, CH4, and CO in a high-pressure cabin, this system needs to select appropriate detection modules according to the characteristics of different gases and adjust the working mode of the gas treatment device according to the detection requirements to ensure the accuracy and reliability of the detection results.

[0005] To achieve the above object, the technical solution of the present invention is as follows: A high-density gas detection system applicable to an ultra-deep saturation living cabin, comprising a high-pressure chamber, a sampling tube, a gas treatment device, a first branch pipe, a second branch pipe, a third branch pipe, an EI source module, a PTR source module, a carbon monoxide detector, a mass spectrometry detection module, and gas detection software; the sampling tube is used to collect gas samples from the high-pressure chamber, and the gas treatment device is used to preprocess the collected gas samples; the sampling tube is connected to the first branch pipe, the second branch pipe, and the third branch pipe. The first branch pipe is used to direct the preprocessed gas samples to the EI source module, the second branch pipe is used to direct the preprocessed gas samples to the PTR source module, and the third branch pipe is used to direct the preprocessed gas samples to the carbon monoxide detector; the mass spectrometry detection module is used to analyze the ionized gas obtained from the EI source module and the PTR source module; the gas detection software is used to process, display, and store the detection data obtained from the carbon monoxide detector and the mass spectrometry detection module.

[0006] Preferably, the EI source module is used to detect CO2, 0-30% or 0-50% O2, and CH4, and is also used for quality control detection of high-purity He, N2, and O2; the PTR source module is used to detect NH3, H2S, and VOCs. The PTR source module includes a high-sensitivity PTR ion source, and realizes ionization and mass spectrometry detection of NH3, H2S, and VOCs through proton transfer reaction ionization; the carbon monoxide detector is based on the cavity ring-down spectroscopy principle and is used to separately detect the CO concentration.

[0007] Preferably, a first valve, a second valve, and a third valve are respectively arranged on the first branch pipe, the second branch pipe, and the third branch pipe.

[0008] Preferably, an electric control valve and a pressure controller are also arranged on the sampling tube.

[0009] Preferably, the gas treatment device is arranged on the outer wall of the sampling tube. The gas treatment device includes a semiconductor refrigeration sheet, a dehumidification ring, a first heat pipe, a heating ring, and a second heat pipe. A dehumidification ring and a first heat pipe are arranged on the lower side of the cold end of the semiconductor refrigeration sheet. The first heat pipe is located in the upper end opening of the dehumidification ring. There is a gap between the upper surfaces of one end of the dehumidification ring and the first heat pipe and the cold end of the semiconductor refrigeration sheet. The hot end of the semiconductor refrigeration sheet is connected to the heating ring through the second heat pipe. The dehumidification ring and the heating ring are sleeved on the outer wall of the sampling tube.

[0010] Preferably, clamping members are provided on both sides of the semiconductor refrigeration sheet. The clamping members are sleeved on the support columns, and the size of the gap is adjusted by adjusting the height of the clamping members. The upper surface of one end of the dehumidification ring or the first heat pipe can be coated with thermal conductive silicone grease to contact the cold end of the semiconductor refrigeration sheet, and the other end of the first heat pipe is arranged on the heat dissipation plate of the EI source module; when the PTR source module is working or the carbon monoxide detector is working, the upper surface of the dehumidification ring is coated with thermal conductive silicone grease, and when the EI source module is working, the upper surface of one end of the first heat pipe is coated with thermal conductive silicone grease.

[0011] Preferably, a heat dissipation plate is provided at the top of the heating ring. One end of the second heat pipe is lapped on the hot end of the semiconductor refrigeration sheet, and the other end of the second heat pipe is lapped on the heat dissipation plate.

[0012] Preferably, a support member made of heat insulation material is provided between the lower surface of one end of the first heat pipe and the sampling pipe, and the lower surface of the support member is an arc surface adapted to the sampling pipe.

[0013] The present invention also discloses a detection method for a high-density gas detection system applicable to an ultra-large-depth saturation living cabin, including the following steps:

[0014] S1, collecting a gas sample from the high-pressure chamber through the sampling pipe;

[0015] S2, selecting different detection modules according to the type of gas to be detected, and determining the working mode of the gas treatment device:

[0016] S3, the collected gas sample flows through the gas treatment device and enters the detection module;

[0017] S4, in the EI source module, ionizing and mass spectrometric detecting the gas sample through an electron bombardment source; in the PTR source module, ionizing and mass spectrometric detecting the gas sample through a proton transfer reaction ionization method; analyzing the ionized gas obtained from the EI source module and the PTR source module through a mass spectrometry detection module; in the carbon monoxide detector, separately detecting the CO concentration based on the cavity ring-down spectroscopy principle;

[0018] S5, processing, displaying and storing the detection data obtained from the carbon monoxide detector and the mass spectrometry detection module through gas detection software.

[0019] Preferably, in step S2, when the gas to be detected is CO2, 0 - 30% or 0 - 50% O2, CH4, or high-purity He, N2, and O2, the gas sample is selected to be directed to the EI source module through the first branch pipe, and the gas treatment device does not perform dehumidification treatment; when the gas to be detected is NH3, H2S, and VOCs, the gas sample is selected to be directed to the PTR source module through the second branch pipe, and the gas treatment device performs dehumidification treatment; when the gas to be detected is CO, the gas sample is selected to be directed to the carbon monoxide detector through the third branch pipe, and the gas treatment device performs dehumidification treatment.

[0020] The beneficial effects of the present invention are as follows:

[0021] (1) The system of the present invention can realize real-time on-line detection of multiple gas components. After the gas sample enters the system through the sampling pipe, it is pre-treated by the gas treatment device, and then automatically switched through different branch pipes to the corresponding detection module, and finally the data analysis and display are carried out through the mass spectrometry detection module and the gas detection software. The whole process realizes the automation and high efficiency of gas detection. By combining the EI source, PTR source, and cavity ring-down spectroscopy technology, the present invention can detect multiple gas components in the hyperbaric chamber, including CO2, O2, CH4, NH3, H2S, and CO, etc., and has high precision and high sensitivity, and can quickly respond to the change of gas concentration to ensure that the gas components in the chamber are always within the safe range.

[0022] (2) The gas treatment device in the system of the present invention can automatically adjust the humidity treatment method according to the detection requirements of different gases. For example, when using the PTR source and the carbon monoxide detector, the gas treatment device will perform dehumidification treatment to reduce the influence of water vapor on the detection sensitivity; while when using the EI source mass spectrometry detection, no dehumidification treatment is required. This flexible humidity treatment method ensures accurate detection results under various environmental conditions.

[0023] (3) The present invention solves the interference problem existing in the detection of multiple gases. For example, by calculating the signal intensity of O2 in real time and subtracting the signal intensity of O2 from the total signal of M / Z 16, the pure signal intensity of CH4 is obtained, thereby calculating the CH4 gas concentration, solving the oxygen interference problem and improving the accuracy of the detection result; the high-precision carbon monoxide detector separately detects the carbon monoxide concentration, and the detection result is sent to the gas detection software in real time, which can provide a subtraction base for the nitrogen concentration in the chamber and the mass spectrometry detection. + Signal intensity to calculate O + Signal intensity, and subtract the O + Signal intensity from the total signal of M / Z 16 to obtain the pure CH4 + Signal intensity, thereby calculating the CH4 gas concentration, solving the oxygen interference problem, and improving the accuracy of the detection result; the high-precision carbon monoxide detector separately detects the carbon monoxide concentration, and the detection result is sent to the gas detection software in real time, which can provide a subtraction base for the nitrogen concentration in the chamber and the mass spectrometry detection. Description of the Drawings

[0024] One or more embodiments are illustrated by corresponding drawings. These illustrative descriptions do not limit the embodiments. Elements with the same reference numerals in the drawings represent similar elements, unless otherwise stated. The figures in the drawings do not constitute a scale limitation.

[0025] Figure 1 It is a schematic diagram of the overall high-density gas detection system applicable to the ultra-large depth saturation living cabin shown in the embodiments of the present invention;

[0026] Figure 2 It is a schematic diagram of the overall sampling tube and gas treatment device shown in the embodiments of the present invention;

[0027] Figure 3 It is a schematic diagram of another angle of the sampling tube and gas treatment device shown in the embodiments of the present invention;

[0028] Figure 4 It is a schematic diagram of some parts of the sampling tube and gas treatment device shown in the embodiments of the present invention;

[0029] Figure 5 It is a top view of the sampling tube and gas treatment device shown in the embodiments of the present invention;

[0030] Figure 6 It is a sectional view of the sampling tube and gas treatment device shown in the embodiments of the present invention;

[0031] Figure 7 It is a schematic diagram of the process flow of the high-density gas detection method applicable to the ultra-large depth saturation living cabin shown in the embodiments of the present invention.

[0032] Reference numerals: 1 - high-pressure chamber, 2 - sampling tube, 3 - gas treatment device, 4 - first branch pipe, 5 - second branch pipe, 6 - third branch pipe, 7 - EI source module, 8 - PTR source module, 9 - carbon monoxide detector, 10 - mass spectrometry detection module, 11 - gas detection software, 12 - semiconductor refrigeration chip, 13 - dehumidification ring, 14 - first heat pipe, 15 - heating ring, 16 - second heat pipe, 17 - gap, 18 - clamping member, 19 - support column, 20 - heat spreader, 21 - support member, 22 - electric control valve, 23 - pressure controller, 24 - first valve, 25 - second valve, 26 - third valve. Detailed implementation manners

[0033] For the convenience of understanding the present invention, the present invention will be described in more detail below with reference to the accompanying drawings and specific embodiments. It should be noted that when an element is expressed as "fixed to" another element, it can be directly on the other element, or there can be one or more intermediate elements therebetween. When an element is expressed as "connected to" another element, it can be directly connected to the other element, or there can be one or more intermediate elements therebetween. The terms "vertical", "horizontal", "left", "right", "inner", "outer" and similar expressions used in this specification are only for the purpose of illustration. In the description of the present invention, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating relative importance or implicitly indicating the quantity of the indicated technical features. Thus, unless otherwise stated, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features; the meaning of "a plurality" is two or more. The term "comprising" and any deformation thereof means non-exclusive inclusion, and there may be or be added one or more other features, integers, steps, operations, units, components and / or their combinations.

[0034] In addition, unless otherwise clearly defined and limited, the terms "installed", "connected", "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, or the communication inside two elements. All the technical and scientific terms used in this specification have the same meaning as commonly understood by those skilled in the technical field to which the present invention belongs. The terms used in the description of the present invention are only for the purpose of describing specific embodiments and are not used to limit the present invention. The term "and / or" used in this specification includes any and all combinations of one or more of the related listed items.

[0035] In addition, the technical features involved in different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0036] Please refer to Figures 1-6 , this embodiment provides a high-density gas detection system applicable to an ultra-large depth saturation living cabin, including a high-pressure chamber 1, a sampling pipe 2, a gas treatment device 3, a first branch pipe 4, a second branch pipe 5, a third branch pipe 6, an EI source module 7, a PTR source module 8, a carbon monoxide detector 9, a mass spectrometry detection module 10, and a gas detection software 11.

[0037] The sampling tube 2 is used to collect gas samples from the high-pressure chamber 1. These samples contain mixed gases such as helium, oxygen, carbon dioxide, moisture, and nitrogen in the high-pressure chamber 1. The gas processing device 3 is used to preprocess the collected gas samples, including removing water vapor to improve the detection accuracy. The sampling tube 2 is connected to the first branch pipe 4, the second branch pipe 5, and the third branch pipe 6. The first branch pipe 4 is used to direct the preprocessed gas samples to the EI source module 7. The EI source module 7 is used to detect CO2, 0 - 30% or 0 - 50% of O2, and CH4, and is also used for quality control detection of high-purity He, N2, and O2. The EI source module 7, that is, the electron impact ionization source, directly measures CO2, 0 - 30% or 0 - 50% of O2, and CH4 through the electron impact source, and realizes the full-spectrum detection of high-purity He, N2, and O2 through the electron impact source. The second branch pipe 5 is used to direct the preprocessed gas samples to the PTR source module 8. The PTR source module 8 is used to detect NH3, H2S, and VOCs. The PTR source module 8 includes a high-sensitivity PTR ion source, and realizes the ionization and mass spectrometry detection of NH3, H2S, and VOCs through the proton transfer reaction ionization method. The PTR source module 8, that is, the proton transfer reaction source, realizes the ionization of gas molecules through the proton transfer reaction. The proton transfer reaction source uses H3O⁺ ions generated by water vapor, and these ions collide with the gas molecules to be measured, transferring protons to the gas molecules to ionize them. The third branch pipe 6 is used to direct the preprocessed gas samples to the carbon monoxide detector 9. The carbon monoxide detector 9 separately detects CO based on the cavity ring-down spectroscopy principle. The cavity ring-down spectroscopy technology determines the concentration of CO in the gas sample by measuring the ring-down time of light in a high-reflectivity cavity. The mass spectrometry detection module 10 is used to analyze the ionized gas obtained from the EI source module 7 and the PTR source module 8, and realizes the accurate measurement of gas components through high-precision mass spectrometry analysis. The gas detection software 11 is used to process, display, and store the detection data obtained from the carbon monoxide detector 9 and the mass spectrometry detection module 10, ensuring real-time monitoring and recording of the changes in the gas environment in the cabin, and guaranteeing the health and safety of divers.

[0038] The first valve 24, the second valve 25, and the third valve 26 are respectively arranged on the first branch pipe 4, the second branch pipe 5, and the third branch pipe 6. These valves are used to control the flow direction and flow rate of gas samples between different branch pipes. By adjusting these valves, the precise distribution of gas samples between each detection module can be realized, ensuring that each module can receive the required gas samples for detection. In addition, an electric control valve 22 and a pressure controller 23 are also arranged on the sampling tube 2. The electric control valve 22 is used to automatically adjust the gas flow rate, and the pressure controller 23 is used to adjust the high-pressure gas samples collected from the high-pressure chamber 1 to the atmospheric pressure state to ensure that the gas samples maintain a stable pressure level before entering the detection module. This design not only improves the automation degree of the system but also ensures the accuracy and reliability of the detection results.

[0039] The gas treatment device 3 is arranged on the outer wall of the sampling tube 2. The gas treatment device 3 includes a semiconductor refrigeration sheet 12, a dehumidification ring 13, a first heat pipe 14, a heating ring 15, and a second heat pipe 16. The semiconductor refrigeration sheet 12 generates cold to condense the moisture in the gas, ensuring the dryness of the sample gas. A dehumidification ring 13 and a first heat pipe 14 are arranged on the lower side of the cold end of the semiconductor refrigeration sheet 12. The first heat pipe 14 is located in the upper opening of the dehumidification ring 13 and does not contact the dehumidification ring 13, with a gap therebetween. There is a gap 17 between the upper surfaces of one ends of the dehumidification ring 13 and the first heat pipe 14 and the cold end of the semiconductor refrigeration sheet 12. This gap 17 is used to control the efficiency of cold transfer, enabling efficient dehumidification by filling thermal conductive silicone grease when dehumidification is required, and maintaining an air gap to avoid cold transfer when not needed. The hot end of the semiconductor refrigeration sheet 12 is connected to the heating ring 15 through the second heat pipe 16 to ensure that the heat generated during the refrigeration process can be effectively dissipated. The heating ring 15 is sleeved on the outer wall of the sampling tube 2, and the sampling tube 2 is heat-insulated through the setting of the heating ring 15, that is, the temperature on the heat-insulated pipe section is between 40°C and 90°C, preventing the sample gas from condensing on the inner wall of the pipeline due to low temperature during transmission.

[0040] Clamping members 18 are arranged on both sides of the semiconductor refrigeration sheet 12. The clamping members 18 are used to fix and stabilize the position of the semiconductor refrigeration sheet 12. The clamping members 18 are sleeved on the support columns 19 so that they can move up and down along the support columns 19. By adjusting the height of the clamping members 18, the size of the gap 17 can be adjusted. When the gap 17 is large, it is convenient to apply thermal conductive silicone grease. After the application is completed, the gap 17 can be adjusted to be smaller. In addition, the size of the gap 17 can also control the amount and efficiency of cold transfer. The upper surface of one end of the dehumidification ring 13 or the first heat pipe 14 can be coated with thermal conductive silicone grease to contact the cold end of the semiconductor refrigeration sheet 12. To improve the heat conduction efficiency, thermal conductive silicone grease can be coated on the upper surface of one end of the dehumidification ring 13 or the first heat pipe 14 to make it closely contact the cold end of the semiconductor refrigeration sheet 12. The other end of the first heat pipe 14 is arranged on the heat dissipation plate of the EI source module 7 to effectively conduct heat to the heat dissipation plate and help the electron bombardment ionization source dissipate heat. When the PTR source module 8 is working or the carbon monoxide detector 9 is working, the upper surface of the dehumidification ring 13 is coated with thermal conductive silicone grease. When the EI source module 7 is working, the upper surface of one end of the first heat pipe 14 is coated with thermal conductive silicone grease.

[0041] When the PTR source module 8 is working, the upper surface of the dehumidification ring 13 is coated with thermal conductive silicone grease. In this detection mode, by coating the upper surface of the dehumidification ring 13 with thermal conductive silicone grease, the dehumidification effect can be enhanced and the dryness of the gas can be improved. At this time, the upper surface of one section of the first heat pipe 14 is not coated with thermal conductive silicone grease to ensure that all the cold energy can be transferred to the dehumidification ring 13. Proton transfer reaction mass spectrometry is very sensitive to water vapor, and it is necessary to ensure that the sample gas is as dry as possible to improve the accuracy and sensitivity of detection. For example, when detecting H2S gas, water vapor greatly affects the detection. The dehumidification ring 13 can remove more than 90% of the water in the sample to be detected, and at the same time, the adsorption rate of H2S is less than 5%. A drain hole (not shown in the figure) can also be provided on the sampling tube 2. The drain hole is used to discharge the condensed water liquid to prevent water from accumulating in the tube. A water permeable membrane is provided on the drain hole. The water permeable membrane can allow water to be discharged without affecting the flow of the gas, ensuring the continuity and efficiency of gas treatment.

[0042] When the carbon monoxide detector 9 is working, the upper surface of the dehumidification ring 13 is coated with thermal conductive silicone grease. In this detection mode, by coating the upper surface of the dehumidification ring 13 with thermal conductive silicone grease, the dehumidification effect can be enhanced and the dryness of the gas can be improved. At this time, the upper surface of one section of the first heat pipe 14 is not coated with thermal conductive silicone grease to ensure that all the cold energy can be transferred to the dehumidification ring 13. The carbon monoxide detector 9 is based on the principle of cavity ring-down spectroscopy and has high requirements for humidity. The cavity ring-down spectroscopy technology detects the gas concentration by measuring the decay time of light in a high-reflectivity optical cavity. The presence of water vapor will absorb and scatter light, interfering with the transmission and decay process of light and resulting in inaccurate detection results.

[0043] When the EI source module 7 is working, the upper surface of one end of the first heat pipe 14 is coated with thermal conductive silicone grease. At this time, the upper surface of the dehumidification ring 13 can be coated with a small amount of thermal conductive silicone grease or not coated with thermal conductive silicone grease. In the electron impact ionization detection mode, by coating the upper surface of one end of the first heat pipe 14 with thermal conductive silicone grease, the cold energy can be effectively conducted. The other end of the first heat pipe 14 is located on the heating component of the electron impact ionization source to help the electron impact ionization source dissipate heat and ensure its normal operation. The electron impact ionization detection mode is not as sensitive to water vapor as the above two modes and has low requirements for dehumidification. However, a large amount of heat is generated during the operation of the electron impact ionization source, so effective heat dissipation measures are required to maintain its stability and efficiency.

[0044] The above design enables the cold energy to be concentrated on dehumidification when the PTR source module 8 and the carbon monoxide detector 9 are working, ensuring the dryness of the sample gas, thereby improving the sensitivity and accuracy of detection; while when the EI source module 7 is working, the cold energy is mainly used for heat dissipation to ensure the normal operation of the electron impact ionization source. In this way, the device can achieve the best performance and reliability under different detection modes.

[0045] The top end of the heating ring 15 is provided with a heat sink 20. The heat sink 20 is installed at the top end of the heating ring 15 and is used to evenly distribute heat, ensuring that the heat transferred by the second heat pipe 16 can be evenly transferred to the sampling tube 2. One end of the second heat pipe 16 is lapped on the hot end of the thermoelectric cooler 12, and the other end of the second heat pipe 16 is lapped on the heat sink 20, evenly distributing the heat conducted from the thermoelectric cooler 12 to the heat sink 20, and then transferring it to the sampling tube 2 through the heating ring 15, preventing the sample gas from condensing on the inner wall of the pipeline due to low temperature during the transmission process.

[0046] A support 21 made of heat-insulating material is provided between the lower surface of one end of the first heat pipe 14 and the sampling tube 2 for support and heat insulation. The lower surface of the support 21 is an arc surface adapted to the sampling tube 2, ensuring that the support 21 can be stably fixed on the sampling tube 2, providing support for one section of the first heat pipe 14 while providing an effective heat insulation function, preventing heat from being directly conducted to the sampling tube 2 and affecting the temperature control of the gas sample.

[0047] The thermoelectric cooler 12 adopted in the present invention utilizes the Peltier effect to generate a temperature difference at both ends through the flow of current, with one end being the cold end and the other end being the hot end. The temperature of the cold end can be reduced to close to 0°C or even lower, thereby condensing and removing water vapor. Compared with other dehumidification methods, such as Nafion tube dehumidification and adsorbent dehumidification, semiconductor cooling dehumidification has a mild effect. While effectively removing water vapor, the analyte is basically not lost, maintaining the integrity and accuracy of the sample. In addition, semiconductor dehumidification is a dehumidification method with adjustable humidity. By adjusting the temperature of the thermoelectric cooler, different degrees of dehumidification of the sample to be measured can be achieved. For example, 100% dehumidification, 40% dehumidification, or 20% dehumidification can be realized according to actual needs. By utilizing the heat generated by the thermoelectric cooler, it is further possible to prevent the condensation and adsorption of the sample gas on the inner wall of the pipeline, ensuring the complete transmission of the sample gas and improving the accuracy of detection. The semiconductor dehumidification system can work as long as it is powered on, is small in size, has no vibration and noise, and is very suitable for integration with a mass spectrometry device.

[0048] The heat pipe adopted in the present invention is a high-efficiency heat transfer element filled with a heat-conducting medium, which can quickly conduct heat. The heat-conducting medium filled in the heat pipe can quickly move under the drive of the temperature difference at both ends, thereby realizing high-efficiency heat transfer, especially for heat transfer over a long distance.

[0049] Furthermore, considering that the temperature of the insulation section of the sampling tube 2 needs to be maintained at 40°C to 90°C, a heat-insulating material can be wrapped around the heating ring 15. The heat-insulating material is used to reduce heat loss, ensure the maximum thermal efficiency of the heating ring 15, and improve the heating efficiency. At the same time, to avoid excessive temperature, a temperature sensor can be set on the insulation section of the sampling tube 2. The temperature sensor monitors the temperature of the sampling tube 2 in real time and adjusts the power of the semiconductor refrigeration chip 12 based on the feedback signal of the temperature sensor. By dynamically adjusting the power of the semiconductor refrigeration chip 12, the temperature of the heating ring 15 can be accurately controlled and maintained within the set range.

[0050] To address the temperature difference problem between the dehumidification section of the sampling tube 2 corresponding to the dehumidification ring 13 and the insulation section of the sampling tube 2 corresponding to the heating ring 15, the present invention designs the structure of the sampling tube 2 by increasing the distance between the two positions. The sampling tube 2 is made of polytetrafluoroethylene or stainless steel material, which has a low thermal conductivity and can effectively reduce heat conduction, ensuring the independence of the temperatures of the dehumidification ring 13 and the heating ring 15. In addition, an insulating section is designed on the sampling tube 2 between the dehumidification ring 13 and the heating ring 15. The insulating section has an adiabatic effect, with one end connected to the dehumidification section where the dehumidification ring 13 is located and the other end connected to the insulation section where the heating ring 15 is located, forming a complete insulating structure. The insulating section is designed with a detachable structure, which is convenient for installation and maintenance, and at the same time ensures the reliability of the insulating effect. The inside of the insulating section can be filled with insulating materials or adopt a multi-layer structure with air or other insulating media in the middle to further enhance the insulating effect. Through this design, the present invention can effectively overcome the temperature difference problem between the dehumidification ring 13 and the heating ring 15 on the sampling tube 2, ensure the temperature independence and stability of each functional section, and thus improve the detection sensitivity and accuracy of the device. At the same time, the use of polytetrafluoroethylene material or stainless steel material and the insulating section further optimizes the thermal management performance of the sampling tube 2, improving the overall reliability and service life of the device.

[0051] Furthermore, a convex ring (not shown in the figure) can be formed on the inner wall surface corresponding to the insulation section of the sampling tube 2, and the convex ring is smoothly connected to the inner wall surface of the sampling tube 2. The purpose of the convex ring design is to increase the air flow disturbance and reduce the formation of the boundary layer, thereby further reducing the adsorption of the sample gas. The smooth connection between the convex ring and the inner wall surface of the sampling tube 2 avoids dead ends and ensures the smoothness of the gas flow.

[0052] Please refer to Figure 7 , another embodiment of the present invention also discloses a detection method based on the above-mentioned high-density gas detection system applicable to a super-deep saturation living cabin, including the following steps:

[0053] S1, collect a gas sample from the high-pressure chamber 1 through the sampling tube 2;

[0054] S2. Select different detection modules according to the type of gas to be detected, and determine the working mode of the gas treatment device 3;

[0055] S3. The collected gas sample flows through the gas treatment device 3 and enters the detection module;

[0056] S4. In the EI source module 7, the gas sample is ionized and mass-spectrometrically detected by an electron impact source. In the PTR source module 8, the gas sample is ionized and mass-spectrometrically detected by proton transfer reaction ionization. The ionized gas obtained from the EI source module 7 and the PTR source module 8 is analyzed by the mass spectrometry detection module 10. In the carbon monoxide detector 9, the CO concentration is separately detected based on the principle of cavity ring-down spectroscopy;

[0057] S5. The detection data obtained from the carbon monoxide detector 9 and the mass spectrometry detection module 10 are processed, displayed, and stored by the gas detection software 11; these data are used for real-time monitoring and analysis of the changes in the gas composition in the cabin to ensure the safety and health of the divers.

[0058] Further, in step S2, when the gas to be detected is CO2, 0 - 30% or 0 - 50% O2, CH4, or high-purity He, N2, and O2, select to direct the gas sample to the EI source module 7 through the first branch pipe 4, and the gas treatment device 3 does not perform dehumidification treatment. When these gases are ionized by electron impact in the EI source module, they are not sensitive to humidity, so dehumidification treatment is not required to ensure the accuracy and precision of the detection. When the gas to be detected is NH3, H2S, and VOCs, select to direct the gas sample to the PTR source module 8 through the second branch pipe 5, and the gas treatment device 3 performs dehumidification treatment. These gases are ionized by proton transfer reaction in the PTR source module and are very sensitive to humidity, so dehumidification treatment is required first to improve the detection sensitivity and accuracy. When the gas to be detected is CO, select to direct the gas sample to the carbon monoxide detector 9 through the third branch pipe 6, and the gas treatment device 3 performs dehumidification treatment. The carbon monoxide detector is based on the principle of cavity ring-down spectroscopy and also has high requirements for humidity, so dehumidification treatment can ensure the accuracy and stability of the detection results.

[0059] For the detection of CO gas, there is a problem that it is difficult to distinguish between N2 and CO with the same molecular weight (both are 28) in mass spectrometry detection. A high-precision carbon monoxide detector based on the principle of cavity ring-down spectroscopy is used to separately detect the CO concentration, and the detection results are sent to the gas detection software in real time, which can also provide a deduction base for the N2 concentration in the cabin and mass spectrometry detection. For the detection of CH4 gas, ionization treatment is carried out through a 70eV electron impact ionization source to generate CH4 + and O + ions. Since O + ions interfere with the M / Z 16 signal, the system uses O2+ Real-time calculation of the signal intensity O + of the signal intensity, and deduct the calculated O from the total M / Z 16 signal + signal intensity, so as to obtain pure CH4 + signal intensity, based on the corrected CH4 + signal intensity to calculate the CH4 gas concentration. For the detection of three high-purity gases, namely He (95%-100%), N2 (95%-100%), and O2 (95%-100%), the EI source mass spectrometry mode is adopted, and the full-spectrum detection of high-purity He, N2, and O2 gases is realized through electron bombardment to obtain the gas concentration.

[0060] In summary, the present invention provides a high-density gas detection system and method applicable to an ultra-large-depth saturation living cabin. Through innovative design and precise technical means, efficient and accurate detection of multiple gas components under high-pressure environment is achieved. The system includes a high-pressure chamber, a sampling tube, a gas treatment device, multiple detection modules (EI source module, PTR source module, and carbon monoxide detector), a mass spectrometry detection module, and a gas detection software. Through the collaborative work of these components, the present invention can monitor and analyze multiple gases in the high-pressure chamber in real time, including CO2, O2, CH4, He, N2, NH3, H2S, VOCs, and CO, etc. During the detection process, the system selects appropriate detection modules according to the characteristics of different gases, and adjusts the humidity through the gas treatment device to ensure the sensitivity and accuracy of the detection. For example, the EI source module is suitable for the detection of humidity-insensitive gases, while the PTR source module and the carbon monoxide detector improve the detection accuracy through dehumidification treatment. In addition, the application of the mass spectrometry detection module and the gas detection software realizes the comprehensive analysis and data storage of various gases, ensuring the reliability and real-time nature of the detection results. Through the present invention, many problems in the gas detection in the high-pressure chamber of the prior art are solved, and a method and system capable of accurately and stably detecting multiple gas components under high-pressure and high-humidity environment are provided. This not only improves the efficiency and accuracy of gas detection under high-pressure environment, but also provides a reliable guarantee for the safety and health of divers.

[0061] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than limiting it; under the idea of the present invention, the technical features in the above embodiments or different embodiments can also be combined, and the steps can be implemented in any order, and there are many other variations in different aspects of the present invention as described above. For the sake of brevity, they are not provided in detail; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A high-density gas detection system suitable for use in ultra-deep saturation living cabins, characterized in that: The invention comprises a high-pressure chamber (1), a sampling tube (2), a gas processing device (3), a first branch pipe (4), a second branch pipe (5), a third branch pipe (6), an EI source module (7), a PTR source module (8), a carbon monoxide detector (9), a mass spectrometer detection module (10), and gas detection software (11); the sampling tube (2) is used to collect gas samples from the high-pressure chamber (1), and the gas processing device (3) is used to pre-treat the collected gas samples; the sampling tube (2) is connected to the first branch pipe (4), the second branch pipe (5), and the third branch pipe (6); the first branch pipe (4) is used to guide the pre-treated gas sample to the EI source module (7); ), the second branch pipe (5) is used to guide the pretreated gas sample to the PTR source module (8), and the third branch pipe (6) is used to guide the pretreated gas sample to the carbon monoxide detector (9); the mass spectrometer detection module (10) is used to analyze the ionized gas obtained from the EI source module (7) and the PTR source module (8); the gas detection software (11) is used to process, display and store the detection data obtained from the carbon monoxide detector (9) and the mass spectrometer detection module (10); the gas processing device (3) is arranged on the outer wall of the sample injection tube (2), and the gas processing device (3) includes a semiconductor refrigeration sheet (12), a dehumidification ring (13), a first heat pipe ( 14), a heating ring (15), and a second heat pipe (16); a dehumidification ring (13) and a first heat pipe (14) are arranged on the lower side of the cold end of the semiconductor refrigeration sheet (12); the first heat pipe (14) is located in the upper opening of the dehumidification ring (13); a gap (17) exists between the upper surface of one end of the dehumidification ring (13) and the first heat pipe (14) and the cold end of the semiconductor refrigeration sheet (12); the hot end of the semiconductor refrigeration sheet (12) is connected to the heating ring (15) through the second heat pipe (16); the dehumidification ring (13) and the heating ring (15) are sleeved on the outer wall of the sample injection tube (2); clamping members are arranged on both sides of the semiconductor refrigeration sheet (12); (18), the clamping member (18) is sleeved on the support column (19), and the size of the gap (17) is adjusted by adjusting the height of the clamping member (18); the upper surface of the dehumidification ring (13) or one end of the first heat pipe (14) can be coated with thermal conductive silicone grease to contact the cold end of the semiconductor refrigeration plate (12), and the other end of the first heat pipe (14) is arranged on the heat dissipation plate of the EI source module (7); when the PTR source module (8) is working or the carbon monoxide detector (9) is working, the upper surface of the dehumidification ring (13) is coated with thermal conductive silicone grease, and when the EI source module (7) is working, the upper surface of one end of the first heat pipe (14) is coated with thermal conductive silicone grease.

2. The high-density gas detection system suitable for use in a super-deep saturation living cabin according to claim 1, characterized in that: The EI source module (7) is used to detect CO2, 0-30% or 0-50% O2 and CH4, and is also used for quality control detection of high-purity He, N2 and O2; the PTR source module (8) is used to detect NH3, H2S and VOCs, and the PTR source module (8) includes a high-sensitivity PTR ion source, which realizes ionization and mass spectrometry detection of NH3, H2S and VOCs through proton transfer reaction ionization; the carbon monoxide detector (9) is based on the principle of cavity ring-down spectroscopy and is used to detect CO concentration alone.

3. The high-density gas detection system suitable for use in a super-deep saturation living cabin according to claim 1, characterized in that: The first branch pipe (4) is provided with a first valve (24), the second branch pipe (5) is provided with a second valve (25), and the third branch pipe (6) is provided with a third valve (26).

4. The high-density gas detection system suitable for use in a super-deep saturation living cabin according to claim 1, characterized in that: The sample injection tube (2) is also provided with an electric regulating valve (22) and a pressure controller (23).

5. The high-density gas detection system suitable for use in a super-deep saturation living cabin according to claim 1, characterized in that: A heat spreader (20) is provided at the top end of the heating ring (15); one end of the second heat pipe (16) is overlapped on the hot end of the semiconductor cooling plate (12); and the other end of the second heat pipe (16) is overlapped on the heat spreader (20).

6. The high-density gas detection system suitable for use in a super-deep saturation living cabin according to claim 5, characterized in that: A support member (21) made of a heat insulating material is provided between the lower surface of one end of the first heat pipe (14) and the sample injection tube (2), and the lower surface of the support member (21) is an arc-shaped surface adapted to the sample injection tube (2).

7. A detection method for a high-density gas detection system suitable for use in a super-deep saturation living cabin based on claim 1, characterized in that: The following steps are involved: S1, collecting a gas sample from a high pressure chamber (1) through a sampling tube (2); S2, according to the type of gas to be detected, select different detection modules and determine the working mode of the gas processing device (3): S3, the collected gas sample flows through the gas processing device (3) and enters the detection module; S4, in the EI source module (7), ionizing the gas sample and performing mass spectrometry detection by an electron bombardment source; in the PTR source module (8), ionizing the gas sample and performing mass spectrometry detection by a proton transfer reaction ionization method; analyzing the ionized gas obtained from the EI source module (7) and the PTR source module (8) by a mass spectrometry detection module (10); and in the carbon monoxide detector (9), performing a separate detection of the CO concentration based on the cavity ring-down spectroscopy principle; S5, processing, displaying and storing the detection data obtained from the carbon monoxide detector (9) and the mass spectrometer detection module (10) through the gas detection software (11).

8. The detection method according to claim 7, characterized in that: In step S2, when the gas to be detected is CO2, 0-30% or 0-50% O2, CH4 or high-purity He, N2 and O2, the gas sample is directed to the EI source module (7) through the first branch pipe (4), and the gas processing device (3) does not perform dehumidification treatment; when the gas to be detected is NH3, H2S and VOCs, the gas sample is directed to the PTR source module (8) through the second branch pipe (5), and the gas processing device (3) performs dehumidification treatment; when the gas to be detected is CO, the gas sample is directed to the carbon monoxide detector (9) through the third branch pipe (6), and the gas processing device (3) performs dehumidification treatment.

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