Soil gas collection device, gas collection method, and detection system

Abstract

The present application relates to a kind of soil gas collecting device, gas collecting method and detection system, it is related to geochemical exploration technical field.The present application's soil gas collecting device includes gas collecting container, semi-permeable membrane, water injection component and gas extraction component;The upper end of the gas collecting container is closed and the lower end is open;The semi-permeable membrane is set at the opening;The water injection component is set at the upper end of the gas collecting container, and the water injection component is used to inject water into the gas collecting container;The gas extraction component is set at the upper end of the gas collecting container, and the gas extraction component is used for gas outflow.The technical scheme disclosed in the present application can solve the problem that the existing gas collecting device cannot completely empty air using the method of air exhaust.

Description

Technical Field

[0001] This invention relates to the field of geochemical exploration technology, and in particular to a soil gas collection device, gas collection method and detection system. Background Technology

[0002] If oil and gas reservoirs, carbon dioxide, hydrogen, rare gases, etc., are present in the formation, the gas components will undergo vertical micro-transportation to the shallow surface soil due to differences in substance concentration, formation pressure, and formation temperature, leading to an increase in the concentration of the corresponding gas components in the soil. By measuring the gas components in the soil, it is possible to track and predict oil and gas reservoirs, carbon dioxide, hydrogen, rare gases, etc., in the underlying strata. Existing soil gas sampling methods typically use gas collection devices. Before sampling, it is generally necessary to evacuate the air from the gas channel. However, this method cannot completely remove all air, which reduces the recoverable volume of soil gas and introduces air into the collected soil gas, thus interfering with the sample. Summary of the Invention

[0003] This invention provides a soil gas collection device, a gas collection method, and a detection system, which can solve the problem that existing gas collection devices cannot completely remove air by using the method of evacuation.

[0004] In a first aspect, embodiments of the present invention provide a soil gas collection device, comprising:

[0005] A gas collecting container, wherein the upper end of the gas collecting container is closed and the lower end is open;

[0006] A semi-permeable membrane is disposed at the opening;

[0007] A water injection assembly is disposed at the upper end of the gas collecting container, and the water injection assembly is used to inject water into the gas collecting container; and

[0008] A gas sampling assembly is disposed at the upper end of the gas collection container, and the gas sampling assembly is used for gas outflow.

[0009] In one embodiment, the water injection assembly includes a water injection pipe and a water injection sealing plug disposed on the water injection pipe; the gas extraction assembly includes a gas extraction pipe and a gas extraction sealing plug disposed on the gas extraction pipe.

[0010] In one embodiment, the gas collection device further includes:

[0011] Analyzer;

[0012] The air intake assembly is connected at one end to the air inlet of the analyzer and at the other end to the gas collection container.

[0013] The gas outlet assembly is connected at one end to the gas outlet of the analyzer and at the other end to the gas collection container.

[0014] In one embodiment, the air intake assembly includes an air intake pipe and an air intake valve disposed on the air intake pipe; the air outlet assembly includes an air outlet pipe and an air outlet valve disposed on the air outlet assembly; wherein the length of the air intake pipe extending into the air collection container is greater than the length of the air outlet pipe extending into the air collection container.

[0015] In one embodiment, the length of the air intake pipe extending into the air collection container is greater than half the length of the air collection container.

[0016] Secondly, embodiments of the present invention provide a gas collection method applied to the soil gas collection device described above, comprising:

[0017] Place the gas collection device inside the sampling hole at the sampling point;

[0018] Inject exhaust water into the gas collection container to purge the air from the gas collection container;

[0019] Stop injecting the exhaust water into the gas collection container;

[0020] Based on the gravity of the exhaust water, the exhaust water seeps into the soil around the gas collection device and discharges the soil gas.

[0021] The soil gas is collected through the gas collection container.

[0022] In one implementation, it further includes:

[0023] After a preset balancing time, open the inlet valve and outlet valve, or open the inlet valve to connect the gas collection container to the analyzer;

[0024] The soil gas is detected using the analyzer.

[0025] In one implementation, it further includes:

[0026] After a preset equilibration time, an external sampling device is used to collect the soil gas through a gas sampling tube and transfer it into a transfer bottle.

[0027] In one embodiment, the step of collecting soil gas using an external sampling device through a gas sampling tube and transferring it to a transfer bottle after a preset equilibrium time includes:

[0028] After a preset equilibrium time, if the air pressure above the semipermeable membrane is less than the air pressure below the semipermeable membrane, then a preset volume of the exhaust water is injected into the gas collection container.

[0029] The soil gas was collected using an external sampling device through a gas sampling tube and transferred to a transfer bottle.

[0030] Thirdly, embodiments of the present invention provide a detection system, including the soil gas collection device as described above.

[0031] Compared with existing technologies, the advantages of this invention are as follows: by injecting exhaust water into the gas collection container through a water injection component, the air inside the gas collection container is completely emptied. The exhaust water then seeps into the soil to create negative pressure, drawing soil gas into the gas collection container. This solves the problem that existing gas collection devices using suction methods cannot completely empty the air, preventing air from occupying space in the gas collection container and reducing the collectable volume of soil gas, and preventing air from mixing into the soil gas and interfering with the sample. Furthermore, after injection, the exhaust water seeps into the soil due to its own gravity and the soil's absorbency, thus collecting soil gas at the corresponding burial depth. This achieves targeted, depth-based soil gas collection. Compared to existing gas collection devices that generally use a rotating spiral structure, resulting in compacted soil near the drill bit and only allowing extraction of a small amount of soil gas from that area, this invention collects soil gas at a deeper burial depth by allowing exhaust water to seep into the soil. This results in more representative samples and achieves accurate collection of soil gas from shallow surface soil. Attached Figure Description

[0032] The invention will now be described in more detail with reference to embodiments and the accompanying drawings.

[0033] Figure 1 This is a schematic diagram of the structure of a soil gas collection device provided in an embodiment of the present invention;

[0034] Figure 2 This is a flowchart of a gas collection method provided in another embodiment of the present invention.

[0035] Figure label:

[0036] 10. Gas collection container;

[0037] 20. Semi-permeable membrane;

[0038] 30. Water injection assembly; 310. Water injection pipe; 320. Water injection sealing plug;

[0039] 40. Gas sampling assembly; 410. Gas sampling pipe; 420. Gas sampling sealing plug;

[0040] 50. Analyzer;

[0041] 60. Intake assembly; 610. Intake pipe; 620. Intake valve;

[0042] 710. Air outlet pipe; 720. Air outlet valve. Detailed Implementation

[0043] The invention will now be further described with reference to the accompanying drawings.

[0044] If oil and gas reservoirs, carbon dioxide, hydrogen, rare gases, etc., are present in the formation, the gas components will undergo vertical micro-transportation to the shallow surface soil due to differences in substance concentration, formation pressure, and formation temperature, leading to an increase in the concentration of the corresponding gas components in the soil. By measuring the gas components in the soil, it is possible to track and predict oil and gas reservoirs, carbon dioxide, hydrogen, rare gases, etc., in the underlying strata. Existing soil gas sampling methods typically use gas collection devices. Before sampling, it is generally necessary to evacuate the air from the gas channel. However, this method cannot completely remove all air, which reduces the recoverable volume of soil gas and introduces air into the collected soil gas, thus interfering with the sample.

[0045] Example 1

[0046] like Figure 1 As shown, this embodiment of the invention provides a soil gas collection device, including a gas collection container 10, a semi-permeable membrane 20, a water injection component 30, and a gas collection component 40; the upper end of the gas collection container 10 is closed and the lower end is open; the semi-permeable membrane 20 is disposed at the opening; the water injection component 30 is disposed at the upper end of the gas collection container 10, and the water injection component 30 is used to inject water into the gas collection container 10; the gas collection component 40 is disposed at the upper end of the gas collection container 10, and the gas collection component 40 is used for gas outflow.

[0047] As can be seen from the above, by setting the water injection component 30 to inject exhaust water into the gas collection container 10, the air inside the gas collection container 10 is completely emptied. The exhaust water then seeps into the soil to create negative pressure, causing the soil gas in the soil to be drawn into the gas collection container 10. This solves the problem that existing gas collection devices using suction evacuation methods cannot completely empty the air, preventing air from occupying the space of the gas collection container 10 and reducing the collectable volume of soil gas, and preventing air in the gas collection container 10 from mixing with the soil gas and interfering with the sample. Furthermore, after injection, the exhaust water seeps into the soil due to its own gravity and the soil's water absorption, thus collecting soil gas at the corresponding burial depth. This achieves fixed-point, fixed-depth soil gas collection. Compared to existing gas collection devices that generally use a rotating spiral structure, resulting in compacted soil near the drill bit and only a small amount of soil gas can be extracted from that area, this invention collects soil gas at a deeper burial depth by allowing exhaust water to seep into the soil. This results in more representative samples and achieves accurate collection of soil gas from shallow surface soil.

[0048] It should be noted that the semi-permeable membrane 20 is a selectively permeable membrane that allows only certain molecules and particles to diffuse in and out. Generally, the semi-permeable membrane 20 only allows ions and small molecules to pass through. The semi-permeable membrane 20 in this invention allows unimpeded gas passage and allows water to pass through slowly. For example, the semi-permeable membrane 20 includes, but is not limited to, polyamide membranes and cellulose acetate membranes. In addition, the semi-permeable membrane 20 is fixedly installed at the opening of the gas collection container 10 by a stainless steel mesh.

[0049] It should also be noted that the gas collection container 10 is made of materials including but not limited to glass and stainless steel; the gas collection container 10 has a cylindrical structure, and the diameter and length of the gas collection container 10 are set according to actual needs. For example, it can be set according to the sampling depth and sampling volume. When the sampling depth is deeper, the length of the gas collection container 10 increases accordingly. When the sampling volume is larger, the volume of the gas collection container 10 also increases accordingly, that is, the diameter and length of the gas collection container 10 increase accordingly; the gas collection container 10 can be a one-piece structure or it can be composed of multiple segmented tubes.

[0050] It should also be noted that exhaust water includes, but is not limited to, clean water.

[0051] Example 2

[0052] like Figure 1 As shown, this embodiment of the invention provides a soil gas collection device, including a gas collection container 10, a semi-permeable membrane 20, a water injection component 30, and a gas collection component 40; the upper end of the gas collection container 10 is closed and the lower end is open; the semi-permeable membrane 20 is disposed at the opening; the water injection component 30 is disposed at the upper end of the gas collection container 10, and the water injection component 30 is used to inject water into the gas collection container 10; the gas collection component 40 is disposed at the upper end of the gas collection container 10, and the gas collection component 40 is used for gas outflow.

[0053] As can be seen from the above, by setting the water injection component 30 to inject exhaust water into the gas collection container 10, the air inside the gas collection container 10 is completely emptied. The exhaust water then seeps into the soil to create negative pressure, causing the soil gas in the soil to be drawn into the gas collection container 10. This solves the problem that existing gas collection devices using suction evacuation methods cannot completely empty the air, preventing air from occupying the space of the gas collection container 10 and reducing the collectable volume of soil gas, and preventing air in the gas collection container 10 from mixing with the soil gas and interfering with the sample. Furthermore, after injection, the exhaust water seeps into the soil due to its own gravity and the soil's water absorption, thus collecting soil gas at the corresponding burial depth. This achieves fixed-point, fixed-depth soil gas collection. Compared to existing gas collection devices that generally use a rotating spiral structure, resulting in compacted soil near the drill bit and only a small amount of soil gas can be extracted from that area, this invention collects soil gas at a deeper burial depth by allowing exhaust water to seep into the soil. This results in more representative samples and achieves accurate collection of soil gas from shallow surface soil.

[0054] It should be noted that the semi-permeable membrane 20 is a selectively permeable membrane that allows only certain molecules and particles to diffuse in and out. Generally, the semi-permeable membrane 20 only allows ions and small molecules to pass through. The semi-permeable membrane 20 in this invention allows unimpeded gas passage and allows water to pass through slowly. For example, the semi-permeable membrane 20 includes, but is not limited to, polyamide membranes and cellulose acetate membranes. In addition, the semi-permeable membrane 20 is fixedly installed at the opening of the gas collection container 10 by a stainless steel mesh.

[0055] It should also be noted that the gas collection container 10 is made of materials including but not limited to glass and stainless steel; the gas collection container 10 has a cylindrical structure, and the diameter and length of the gas collection container 10 are set according to actual needs. For example, it can be set according to the sampling depth and sampling volume. When the sampling depth is deeper, the length of the gas collection container 10 increases accordingly. When the sampling volume is larger, the volume of the gas collection container 10 also increases accordingly, that is, the diameter and length of the gas collection container 10 increase accordingly; the gas collection container 10 can be a one-piece structure or it can be composed of multiple segmented tubes.

[0056] It should also be noted that exhaust water includes, but is not limited to, clean water.

[0057] like Figure 1 As shown, in some embodiments, the water injection assembly 30 includes a water injection pipe 310 and a water injection sealing plug 320 disposed on the water injection pipe 310; the gas extraction assembly 40 includes a gas extraction pipe 410 and a gas extraction sealing plug 420 disposed on the gas extraction pipe 410.

[0058] By setting up a water injection pipe 310, a channel is provided for users to inject exhaust water into the gas collection container 10. The gas sampling pipe 410 not only serves as a channel for injecting water to empty the air inside the gas collection container 10, but also provides a channel for users to extract soil gas from the gas collection container 10. Furthermore, by setting up a water injection sealing plug 320 and a sampling sealing plug to seal the water injection pipe 310 and the gas sampling pipe 410 respectively, when exhaust water is injected into the gas collection container 10, the water injection sealing plug 320 and the sampling sealing plug must be removed to achieve water emptying. After water emptying is completed, the water injection sealing plug 320... 0. Sampling sealing plugs are installed on the water injection pipe 310 and the sampling pipe respectively to prevent air from the external environment from entering the gas collection container 10 and interfering with the soil gas sample in the gas collection container 10. When it is necessary to extract soil gas samples from the gas collection container 10, an external sampling device is used to collect soil gas through the gas collection pipe and transfer the soil gas to the transfer bottle through the external sampling device. For example, the external sampling device is a syringe. The syringe punctures the gas collection sealing plug and collects soil gas through the gas collection pipe, so that the gas collection sealing plug does not need to be removed, thus avoiding the exchange of soil gas and air and the loss of authenticity.

[0059] It should be noted that the water injection pipe 310 and the gas sampling pipe 410 are respectively sealed to the gas collection container 10, and the materials of the water injection pipe 310 and the gas sampling pipe 410 are the same as those of the gas collection container 10.

[0060] It should also be noted that the water injection sealing plug 320 and the gas extraction sealing plug 420 are, but are not limited to, made of rubber.

[0061] It should also be noted that the number of water injection components 30 can be set as needed, and can be one or more; this application does not impose any specific restrictions.

[0062] Example 3

[0063] like Figure 1 As shown, this embodiment of the invention provides a soil gas collection device, including a gas collection container 10, a semi-permeable membrane 20, a water injection component 30, and a gas collection component 40; the upper end of the gas collection container 10 is closed and the lower end is open; the semi-permeable membrane 20 is disposed at the opening; the water injection component 30 is disposed at the upper end of the gas collection container 10, and the water injection component 30 is used to inject water into the gas collection container 10; the gas collection component 40 is disposed at the upper end of the gas collection container 10, and the gas collection component 40 is used for gas outflow.

[0064] As can be seen from the above, by setting the water injection component 30 to inject exhaust water into the gas collection container 10, the air inside the gas collection container 10 is completely emptied. The exhaust water then seeps into the soil to create negative pressure, causing the soil gas in the soil to be drawn into the gas collection container 10. This solves the problem that existing gas collection devices using suction evacuation methods cannot completely empty the air, preventing air from occupying the space of the gas collection container 10 and reducing the collectable volume of soil gas, and preventing air in the gas collection container 10 from mixing with the soil gas and interfering with the sample. Furthermore, after injection, the exhaust water seeps into the soil due to its own gravity and the soil's water absorption, thus collecting soil gas at the corresponding burial depth. This achieves fixed-point, fixed-depth soil gas collection. Compared to existing gas collection devices that generally use a rotating spiral structure, resulting in compacted soil near the drill bit and only a small amount of soil gas can be extracted from that area, this invention collects soil gas at a deeper burial depth by allowing exhaust water to seep into the soil. This results in more representative samples and achieves accurate collection of soil gas from shallow surface soil.

[0065] It should be noted that the semi-permeable membrane 20 is a selectively permeable membrane that allows only certain molecules and particles to diffuse in and out. Generally, the semi-permeable membrane 20 only allows ions and small molecules to pass through. The semi-permeable membrane 20 in this invention allows unimpeded gas passage and allows water to pass through slowly. For example, the semi-permeable membrane 20 includes, but is not limited to, polyamide membranes and cellulose acetate membranes. In addition, the semi-permeable membrane 20 is fixedly installed at the opening of the gas collection container 10 by a stainless steel mesh.

[0066] It should also be noted that the gas collection container 10 is made of materials including but not limited to glass and stainless steel; the gas collection container 10 has a cylindrical structure, and the diameter and length of the gas collection container 10 are set according to actual needs. For example, it can be set according to the sampling depth and sampling volume. When the sampling depth is deeper, the length of the gas collection container 10 increases accordingly. When the sampling volume is larger, the volume of the gas collection container 10 also increases accordingly, that is, the diameter and length of the gas collection container 10 increase accordingly; the gas collection container 10 can be a one-piece structure or it can be composed of multiple segmented tubes.

[0067] It should also be noted that exhaust water includes, but is not limited to, clean water.

[0068] like Figure 1 As shown, in some embodiments, the water injection assembly 30 includes a water injection pipe 310 and a water injection sealing plug 320 disposed on the water injection pipe 310; the gas extraction assembly 40 includes a gas extraction pipe 410 and a gas extraction sealing plug 420 disposed on the gas extraction pipe 410.

[0069] By setting up a water injection pipe 310, a channel is provided for users to inject exhaust water into the gas collection container 10. The gas sampling pipe 410 not only serves as a channel for injecting water to empty the air inside the gas collection container 10, but also provides a channel for users to extract soil gas from the gas collection container 10. Furthermore, by setting up a water injection sealing plug 320 and a sampling sealing plug to seal the water injection pipe 310 and the gas sampling pipe 410 respectively, when exhaust water is injected into the gas collection container 10, the water injection sealing plug 320 and the sampling sealing plug must be removed to achieve water emptying. After water emptying is completed, the water injection sealing plug 320... 0. Sampling sealing plugs are installed on the water injection pipe 310 and the sampling pipe respectively to prevent air from the external environment from entering the gas collection container 10 and interfering with the soil gas sample in the gas collection container 10. When it is necessary to extract soil gas samples from the gas collection container 10, an external sampling device is used to collect soil gas through the gas collection pipe and transfer the soil gas to the transfer bottle through the external sampling device. For example, the external sampling device is a syringe. The syringe punctures the gas collection sealing plug and collects soil gas through the gas collection pipe, so that the gas collection sealing plug does not need to be removed, thus avoiding the exchange of soil gas and air and the loss of authenticity.

[0070] It should be noted that the water injection pipe 310 and the gas sampling pipe 410 are respectively sealed to the gas collection container 10, and the materials of the water injection pipe 310 and the gas sampling pipe 410 are the same as those of the gas collection container 10.

[0071] It should also be noted that the water injection sealing plug 320 and the gas extraction sealing plug 420 are, but are not limited to, made of rubber.

[0072] It should also be noted that the number of water injection components 30 can be set as needed, and can be one or more; this application does not impose any specific restrictions.

[0073] like Figure 1 As shown, in some embodiments, the gas collection device further includes an analyzer 50, an air inlet assembly 60, and an air outlet assembly; one end of the air inlet assembly 60 is connected to the air inlet of the analyzer 50 and the other end is connected to the gas collection container 10, and one end of the air outlet assembly is connected to the air outlet of the analyzer 50 and the other end is connected to the gas collection container 10.

[0074] By setting up the air inlet assembly 60 and the air outlet assembly, a structural basis is provided for the connection between the gas collection device and the analyzer 50. Soil gas samples can be detected at the sampling point. Compared to existing gas collection devices that cannot be connected to the analyzer 50, this invention achieves on-site, in-situ, real-time, and dynamic detection and monitoring of soil gas. Furthermore, by connecting the air inlet assembly 60 and the air outlet assembly to the air inlet and outlet of the analyzer 50 respectively, a circulation path is formed, allowing soil gas to circulate between the gas collection container 10 and the analyzer 50, thereby enabling internal circulation measurement and achieving continuous, dynamic, and real-time monitoring, further improving the detection effect. Alternatively, the air outlet assembly can be closed, with only the air outlet assembly open, allowing soil gas to enter the analyzer 50 for measurement and then be discharged.

[0075] It should be noted that soil gas includes light hydrocarbons such as CH4, CO2, H2, H2S, He, Ne, and Rn. This information can provide important reference for research on energy, resources, environment, and disasters. Therefore, it is necessary to select the appropriate analyzer 50 according to the target components to be detected. The analyzer 50 includes, but is not limited to, portable chromatographs, sensors, and greenhouse gas infrared detectors.

[0076] Example 4

[0077] like Figure 1 As shown, this embodiment of the invention provides a soil gas collection device, including a gas collection container 10, a semi-permeable membrane 20, a water injection component 30, and a gas collection component 40; the upper end of the gas collection container 10 is closed and the lower end is open; the semi-permeable membrane 20 is disposed at the opening; the water injection component 30 is disposed at the upper end of the gas collection container 10, and the water injection component 30 is used to inject water into the gas collection container 10; the gas collection component 40 is disposed at the upper end of the gas collection container 10, and the gas collection component 40 is used for gas outflow.

[0078] As can be seen from the above, by setting the water injection component 30 to inject exhaust water into the gas collection container 10, the air inside the gas collection container 10 is completely emptied. The exhaust water then seeps into the soil to create negative pressure, causing the soil gas in the soil to be drawn into the gas collection container 10. This solves the problem that existing gas collection devices using suction evacuation methods cannot completely empty the air, preventing air from occupying the space of the gas collection container 10 and reducing the collectable volume of soil gas, and preventing air in the gas collection container 10 from mixing with the soil gas and interfering with the sample. Furthermore, after injection, the exhaust water seeps into the soil due to its own gravity and the soil's water absorption, thus collecting soil gas at the corresponding burial depth. This achieves fixed-point, fixed-depth soil gas collection. Compared to existing gas collection devices that generally use a rotating spiral structure, resulting in compacted soil near the drill bit and only a small amount of soil gas can be extracted from that area, this invention collects soil gas at a deeper burial depth by allowing exhaust water to seep into the soil. This results in more representative samples and achieves accurate collection of soil gas from shallow surface soil.

[0079] It should be noted that the semi-permeable membrane 20 is a selectively permeable membrane that allows only certain molecules and particles to diffuse in and out. Generally, the semi-permeable membrane 20 only allows ions and small molecules to pass through. The semi-permeable membrane 20 in this invention allows unimpeded gas passage and allows water to pass through slowly. For example, the semi-permeable membrane 20 includes, but is not limited to, polyamide membranes and cellulose acetate membranes. In addition, the semi-permeable membrane 20 is fixedly installed at the opening of the gas collection container 10 by a stainless steel mesh.

[0080] It should also be noted that the gas collection container 10 is made of materials including but not limited to glass and stainless steel; the gas collection container 10 has a cylindrical structure, and the diameter and length of the gas collection container 10 are set according to actual needs. For example, it can be set according to the sampling depth and sampling volume. When the sampling depth is deeper, the length of the gas collection container 10 increases accordingly. When the sampling volume is larger, the volume of the gas collection container 10 also increases accordingly, that is, the diameter and length of the gas collection container 10 increase accordingly; the gas collection container 10 can be a one-piece structure or it can be composed of multiple segmented tubes.

[0081] It should also be noted that exhaust water includes, but is not limited to, clean water.

[0082] like Figure 1 As shown, in some embodiments, the water injection assembly 30 includes a water injection pipe 310 and a water injection sealing plug 320 disposed on the water injection pipe 310; the gas extraction assembly 40 includes a gas extraction pipe 410 and a gas extraction sealing plug 420 disposed on the gas extraction pipe 410.

[0083] By setting up a water injection pipe 310, a channel is provided for users to inject exhaust water into the gas collection container 10. The gas sampling pipe 410 not only serves as a channel for injecting water to empty the air inside the gas collection container 10, but also provides a channel for users to extract soil gas from the gas collection container 10. Furthermore, by setting up a water injection sealing plug 320 and a sampling sealing plug to seal the water injection pipe 310 and the gas sampling pipe 410 respectively, when exhaust water is injected into the gas collection container 10, the water injection sealing plug 320 and the sampling sealing plug must be removed to achieve water emptying. After water emptying is completed, the water injection sealing plug 320... 0. Sampling sealing plugs are installed on the water injection pipe 310 and the sampling pipe respectively to prevent air from the external environment from entering the gas collection container 10 and interfering with the soil gas sample in the gas collection container 10. When it is necessary to extract soil gas samples from the gas collection container 10, an external sampling device is used to collect soil gas through the gas collection pipe and transfer the soil gas to the transfer bottle through the external sampling device. For example, the external sampling device is a syringe. The syringe punctures the gas collection sealing plug and collects soil gas through the gas collection pipe, so that the gas collection sealing plug does not need to be removed, thus avoiding the exchange of soil gas and air and the loss of authenticity.

[0084] It should be noted that the water injection pipe 310 and the gas sampling pipe 410 are respectively sealed to the gas collection container 10, and the materials of the water injection pipe 310 and the gas sampling pipe 410 are the same as those of the gas collection container 10.

[0085] It should also be noted that the water injection sealing plug 320 and the gas extraction sealing plug 420 are, but are not limited to, made of rubber.

[0086] It should also be noted that the number of water injection components 30 can be set as needed, and can be one or more; this application does not impose any specific restrictions.

[0087] like Figure 1 As shown, in some embodiments, the gas collection device further includes an analyzer 50, an air inlet assembly 60, and an air outlet assembly; one end of the air inlet assembly 60 is connected to the air inlet of the analyzer 50 and the other end is connected to the gas collection container 10, and one end of the air outlet assembly is connected to the air outlet of the analyzer 50 and the other end is connected to the gas collection container 10.

[0088] By setting up the air inlet assembly 60 and the air outlet assembly, a structural basis is provided for the connection between the gas collection device and the analyzer 50. Soil gas samples can be detected at the sampling point. Compared to existing gas collection devices that cannot be connected to the analyzer 50, this invention achieves on-site, in-situ, real-time, and dynamic detection and monitoring of soil gas. Furthermore, by connecting the air inlet assembly 60 and the air outlet assembly to the air inlet and outlet of the analyzer 50 respectively, a circulation path is formed, allowing soil gas to circulate between the gas collection container 10 and the analyzer 50, thereby enabling internal circulation measurement and achieving continuous, dynamic, and real-time monitoring, further improving the detection effect. Alternatively, the air outlet assembly can be closed, with only the air outlet assembly open, allowing soil gas to enter the analyzer 50 for measurement and then be discharged.

[0089] It should be noted that soil gas includes light hydrocarbons such as CH4, CO2, H2, H2S, He, Ne, and Rn. This information can provide important reference for research on energy, resources, environment, and disasters. Therefore, it is necessary to select the appropriate analyzer 50 according to the target components to be detected. The analyzer 50 includes, but is not limited to, portable chromatographs, sensors, and greenhouse gas infrared detectors.

[0090] like Figure 1 As shown, in some embodiments, the air intake assembly 60 includes an air intake pipe 610 and an air intake valve 620 disposed on the air intake pipe 610; the air outlet assembly includes an air outlet pipe 710 and an air outlet valve 720 disposed on the air outlet assembly; wherein, the length of the air intake pipe 610 extending into the air collection container 10 is greater than the length of the air outlet pipe 710 extending into the air collection container 10.

[0091] The inlet pipe 610 and outlet pipe 710 provide a structural basis for the connection between the gas collection container 10 and the analyzer 50. The inlet valve 620 and outlet valve 720 control the opening and closing of the inlet pipe 610 and outlet pipe 710 respectively. When water is injected and emptied, both the inlet valve 620 and outlet valve 720 are closed. When internal circulation measurement is performed, the inlet valve 620 and outlet valve 720 are opened. When no internal circulation measurement is performed but a normal measurement is performed, the inlet valve 620 is opened and the outlet valve 720 is closed.

[0092] It should be noted that the air inlet pipe 610 and the air outlet pipe 710 are respectively sealed to the air collection container 10, and the materials of the air inlet pipe 610 and the air outlet pipe 710 are the same as those of the air collection container 10.

[0093] Example 5

[0094] like Figure 1As shown, this embodiment of the invention provides a soil gas collection device, including a gas collection container 10, a semi-permeable membrane 20, a water injection component 30, and a gas collection component 40; the upper end of the gas collection container 10 is closed and the lower end is open; the semi-permeable membrane 20 is disposed at the opening; the water injection component 30 is disposed at the upper end of the gas collection container 10, and the water injection component 30 is used to inject water into the gas collection container 10; the gas collection component 40 is disposed at the upper end of the gas collection container 10, and the gas collection component 40 is used for gas outflow.

[0095] As can be seen from the above, by setting the water injection component 30 to inject exhaust water into the gas collection container 10, the air inside the gas collection container 10 is completely emptied. The exhaust water then seeps into the soil to create negative pressure, causing the soil gas in the soil to be drawn into the gas collection container 10. This solves the problem that existing gas collection devices using suction evacuation methods cannot completely empty the air, preventing air from occupying the space of the gas collection container 10 and reducing the collectable volume of soil gas, and preventing air in the gas collection container 10 from mixing with the soil gas and interfering with the sample. Furthermore, after injection, the exhaust water seeps into the soil due to its own gravity and the soil's water absorption, thus collecting soil gas at the corresponding burial depth. This achieves fixed-point, fixed-depth soil gas collection. Compared to existing gas collection devices that generally use a rotating spiral structure, resulting in compacted soil near the drill bit and only a small amount of soil gas can be extracted from that area, this invention collects soil gas at a deeper burial depth by allowing exhaust water to seep into the soil. This results in more representative samples and achieves accurate collection of soil gas from shallow surface soil.

[0096] It should be noted that the semi-permeable membrane 20 is a selectively permeable membrane that allows only certain molecules and particles to diffuse in and out. Generally, the semi-permeable membrane 20 only allows ions and small molecules to pass through. The semi-permeable membrane 20 in this invention allows unimpeded gas passage and allows water to pass through slowly. For example, the semi-permeable membrane 20 includes, but is not limited to, polyamide membranes and cellulose acetate membranes. In addition, the semi-permeable membrane 20 is fixedly installed at the opening of the gas collection container 10 by a stainless steel mesh.

[0097] It should also be noted that the gas collection container 10 is made of materials including but not limited to glass and stainless steel; the gas collection container 10 has a cylindrical structure, and the diameter and length of the gas collection container 10 are set according to actual needs. For example, it can be set according to the sampling depth and sampling volume. When the sampling depth is deeper, the length of the gas collection container 10 increases accordingly. When the sampling volume is larger, the volume of the gas collection container 10 also increases accordingly, that is, the diameter and length of the gas collection container 10 increase accordingly; the gas collection container 10 can be a one-piece structure or it can be composed of multiple segmented tubes.

[0098] It should also be noted that exhaust water includes, but is not limited to, clean water.

[0099] like Figure 1As shown, in some embodiments, the water injection assembly 30 includes a water injection pipe 310 and a water injection sealing plug 320 disposed on the water injection pipe 310; the gas extraction assembly 40 includes a gas extraction pipe 410 and a gas extraction sealing plug 420 disposed on the gas extraction pipe 410.

[0100] By setting up a water injection pipe 310, a channel is provided for users to inject exhaust water into the gas collection container 10. The gas sampling pipe 410 not only serves as a channel for injecting water to empty the air inside the gas collection container 10, but also provides a channel for users to extract soil gas from the gas collection container 10. Furthermore, by setting up a water injection sealing plug 320 and a sampling sealing plug to seal the water injection pipe 310 and the gas sampling pipe 410 respectively, when exhaust water is injected into the gas collection container 10, the water injection sealing plug 320 and the sampling sealing plug must be removed to achieve water emptying. After water emptying is completed, the water injection sealing plug 320... 0. Sampling sealing plugs are installed on the water injection pipe 310 and the sampling pipe respectively to prevent air from the external environment from entering the gas collection container 10 and interfering with the soil gas sample in the gas collection container 10. When it is necessary to extract soil gas samples from the gas collection container 10, an external sampling device is used to collect soil gas through the gas collection pipe and transfer the soil gas to the transfer bottle through the external sampling device. For example, the external sampling device is a syringe. The syringe punctures the gas collection sealing plug and collects soil gas through the gas collection pipe, so that the gas collection sealing plug does not need to be removed, thus avoiding the exchange of soil gas and air and the loss of authenticity.

[0101] It should be noted that the water injection pipe 310 and the gas sampling pipe 410 are respectively sealed to the gas collection container 10, and the materials of the water injection pipe 310 and the gas sampling pipe 410 are the same as those of the gas collection container 10.

[0102] It should also be noted that the water injection sealing plug 320 and the gas extraction sealing plug 420 are, but are not limited to, made of rubber.

[0103] It should also be noted that the number of water injection components 30 can be set as needed, and can be one or more; this application does not impose any specific restrictions.

[0104] like Figure 1 As shown, in some embodiments, the gas collection device further includes an analyzer 50, an air inlet assembly 60, and an air outlet assembly; one end of the air inlet assembly 60 is connected to the air inlet of the analyzer 50 and the other end is connected to the gas collection container 10, and one end of the air outlet assembly is connected to the air outlet of the analyzer 50 and the other end is connected to the gas collection container 10.

[0105] By setting up the air inlet assembly 60 and the air outlet assembly, a structural basis is provided for the connection between the gas collection device and the analyzer 50. Soil gas samples can be detected at the sampling point. Compared to existing gas collection devices that cannot be connected to the analyzer 50, this invention achieves on-site, in-situ, real-time, and dynamic detection and monitoring of soil gas. Furthermore, by connecting the air inlet assembly 60 and the air outlet assembly to the air inlet and outlet of the analyzer 50 respectively, a circulation path is formed, allowing soil gas to circulate between the gas collection container 10 and the analyzer 50, thereby enabling internal circulation measurement and achieving continuous, dynamic, and real-time monitoring, further improving the detection effect. Alternatively, the air outlet assembly can be closed, with only the air outlet assembly open, allowing soil gas to enter the analyzer 50 for measurement and then be discharged.

[0106] It should be noted that soil gas includes light hydrocarbons such as CH4, CO2, H2, H2S, He, Ne, and Rn. This information can provide important reference for research on energy, resources, environment, and disasters. Therefore, it is necessary to select the appropriate analyzer 50 according to the target components to be detected. The analyzer 50 includes, but is not limited to, portable chromatographs, sensors, and greenhouse gas infrared detectors.

[0107] like Figure 1 As shown, in some embodiments, the air intake assembly 60 includes an air intake pipe 610 and an air intake valve 620 disposed on the air intake pipe 610; the air outlet assembly includes an air outlet pipe 710 and an air outlet valve 720 disposed on the air outlet assembly; wherein, the length of the air intake pipe 610 extending into the air collection container 10 is greater than the length of the air outlet pipe 710 extending into the air collection container 10.

[0108] The inlet pipe 610 and outlet pipe 710 provide a structural basis for the connection between the gas collection container 10 and the analyzer 50. The inlet valve 620 and outlet valve 720 control the opening and closing of the inlet pipe 610 and outlet pipe 710 respectively. When water is injected and emptied, both the inlet valve 620 and outlet valve 720 are closed. When internal circulation measurement is performed, the inlet valve 620 and outlet valve 720 are opened. When no internal circulation measurement is performed but a normal measurement is performed, the inlet valve 620 is opened and the outlet valve 720 is closed.

[0109] It should be noted that the air inlet pipe 610 and the air outlet pipe 710 are respectively sealed to the air collection container 10, and the materials of the air inlet pipe 610 and the air outlet pipe 710 are the same as those of the air collection container 10.

[0110] like Figure 1 As shown, in some embodiments, the length of the air intake pipe 610 extending into the air collection container 10 is greater than half the length of the air collection container 10.

[0111] Example 6

[0112] like Figure 2As shown, this embodiment of the invention provides a gas collection method, applied to the soil gas collection device of any embodiment of the invention, thereby achieving all the technical effects brought about by the technical solutions of the above embodiments. The gas collection method includes:

[0113] S101: Place the gas collection device into the sampling hole of the sampling point;

[0114] It should be noted that before placing the gas collection device at the sampling point, a sampling hole must first be dug at the sampling point, including but not limited to using a twist drill or a Luoyang shovel to drill the hole. The depth and diameter of the sampling hole are set according to specific needs. The diameter of the sampling hole is slightly larger than the diameter of the gas collection container 10, and the depth of the sampling hole is less than the length of the gas collection container 10.

[0115] In some embodiments, placing the gas collection device inside the sampling hole of the sampling point includes:

[0116] The gap between the gas collection device and the sampling hole was filled with soil and compacted.

[0117] By filling and compacting the gap between the gas collection device and the sampling hole, a seal is achieved, preventing air from the external environment from entering the gas collection container 10 through the gap and interfering with the soil gas sample.

[0118] S102: Inject exhaust water into the gas collection container 10 to vent the air inside the gas collection container 10;

[0119] In some embodiments, before injecting exhaust water into the gas collection container 10, the water injection sealing plug 320 and the sampling sealing plug are removed, and the air inlet valve 620 and the air outlet valve 720 are closed.

[0120] It should be noted that because a semi-permeable membrane 20 is provided at the bottom of the gas collection container 10, the exhaust water slowly passes through the semi-permeable membrane 20. The injection rate of the exhaust water is greater than the discharge rate of the exhaust water, so the water level in the gas collection container 10 gradually rises, purging the air in the gas collection container 10. This avoids air occupying the volume in the gas collection container 10, which would reduce the usable volume of soil gas and thus reduce the collectable volume of soil gas. It also avoids air mixing into the soil gas and interfering with the soil gas sample.

[0121] S103: Stop injecting exhaust water into the gas collection container 10;

[0122] In some embodiments, stopping the injection of exhaust water into the gas collection container 10 includes installing a water injection sealing plug 320 into the water injection pipe 310 and a gas collection sealing plug 420 into the gas collection pipe 410.

[0123] S104: Based on the gravity of the exhaust water, the exhaust water seeps into the soil around the gas collection device and discharges the soil gas.

[0124] S105: Collect the soil gas through the gas collection container 10.

[0125] It should be noted that, under the influence of gravity of the exhaust gas and the water absorption of the soil, the exhaust water slowly passes through the semi-permeable membrane 20 and seeps into the soil at the buried depth, forming a negative pressure. The gas collection container 10 draws in the soil gas at the buried depth, thereby obtaining soil gas at a fixed point and depth.

[0126] It should also be noted that the volume of soil gas collected is related to the volume of the gas collection container 10. The larger the gas collection container 10 is, the larger the volume of exhaust water injected into the gas collection container 10 will be, and the more exhaust water will seep into the soil. Therefore, the gas collection container 10 will absorb more soil gas.

[0127] In some embodiments, it also includes:

[0128] After the preset balancing time, open the inlet valve 620 and outlet valve 720 of the gas collection device, or open the inlet valve 620 to connect the gas collection container 10 to the analyzer 50.

[0129] The soil gas was detected using an analyzer 50.

[0130] It should be noted that the preset equilibrium time can be set according to specific needs. For example, the preset equilibrium time can be 24 hours. This is because it takes time for the exhaust water to seep into the soil, and it also allows time for the stable equilibrium of soil gas in the gas collection container 10. This ensures the representativeness of the sample, guarantees the collection of soil gas samples, reduces errors, accurately obtains the target components, and provides a guarantee for obtaining real and effective data.

[0131] It should also be noted that after the preset equilibration time, the inlet valve 620 and outlet valve 720 of the gas collection device are opened to connect the gas collection container 10 and the analyzer 50, so that a circulation path for the flow of soil gas is formed between the gas collection container 10 and the analyzer 50. The gas circulation is measured by the analyzer 50, thereby continuously, dynamically and in real time monitoring the soil gas.

[0132] After a preset equilibration time, the air inlet valve 620 of the gas collection device is opened, and the gas collection container 10 is connected to the analyzer 50. The soil gas enters the analyzer 50 for detection, and is then discharged.

[0133] Example 7

[0134] This invention provides a gas collection method, applied to the soil gas collection device of any embodiment of this invention, thereby achieving all the technical effects brought about by the technical solutions of the above embodiments. The gas collection method includes:

[0135] S101: Place the gas collection device into the sampling hole of the sampling point;

[0136] It should be noted that before placing the gas collection device at the sampling point, a sampling hole must first be dug at the sampling point, including but not limited to using a twist drill or a Luoyang shovel to drill the hole. The depth and diameter of the sampling hole are set according to specific needs. The diameter of the sampling hole is slightly larger than the diameter of the gas collection container 10, and the depth of the sampling hole is less than the length of the gas collection container 10.

[0137] In some embodiments, placing the gas collection device inside the sampling hole of the sampling point includes:

[0138] The gap between the gas collection device and the sampling hole was filled with soil and compacted.

[0139] By filling and compacting the gap between the gas collection device and the sampling hole, a seal is achieved, preventing air from the external environment from entering the gas collection container 10 through the gap and interfering with the soil gas sample.

[0140] S102: Inject exhaust water into the gas collection container 10 to vent the air inside the gas collection container 10;

[0141] In some embodiments, before injecting exhaust water into the gas collection container 10, the water injection sealing plug 320 and the sampling sealing plug are removed, and the air inlet valve 620 and the air outlet valve 720 are closed.

[0142] It should be noted that because a semi-permeable membrane 20 is provided at the bottom of the gas collection container 10, the exhaust water slowly passes through the semi-permeable membrane 20. The injection rate of the exhaust water is greater than the discharge rate of the exhaust water, so the water level in the gas collection container 10 gradually rises, purging the air in the gas collection container 10. This avoids air occupying the volume in the gas collection container 10, which would reduce the usable volume of soil gas and thus reduce the collectable volume of soil gas. It also avoids air mixing into the soil gas and interfering with the soil gas sample.

[0143] S103: Stop injecting exhaust water into the gas collection container 10;

[0144] In some embodiments, stopping the injection of exhaust water into the gas collection container 10 includes installing a water injection sealing plug 320 into the water injection pipe 310 and a gas collection sealing plug 420 into the gas collection pipe 410.

[0145] S104: Based on the gravity of the exhaust water, the exhaust water seeps into the soil around the gas collection device and discharges the soil gas.

[0146] S105: Collect the soil gas through the gas collection container 10.

[0147] It should be noted that, under the influence of gravity of the exhaust gas and the water absorption of the soil, the exhaust water slowly passes through the semi-permeable membrane 20 and seeps into the soil at the buried depth, forming a negative pressure. The gas collection container 10 draws in the soil gas at the buried depth, thereby obtaining soil gas at a fixed point and depth.

[0148] It should also be noted that the volume of soil gas collected is related to the volume of the gas collection container 10. The larger the gas collection container 10 is, the larger the volume of exhaust water injected into the gas collection container 10 will be, and the more exhaust water will seep into the soil. Therefore, the gas collection container 10 will absorb more soil gas.

[0149] In some embodiments, it also includes:

[0150] After a preset equilibration time, an external sampling device is used to collect soil gas through the gas sampling pipe 410 and transfer it into a transfer bottle.

[0151] It should be noted that when the target detection component cannot be detected on-site at the sampling point, the soil gas can be extracted from the gas sampling tube 410 using a syringe, transferred to a transfer bottle, and then brought back to the laboratory for analysis.

[0152] It should also be noted that the external sampling device includes, but is not limited to, a syringe. The syringe pierces the gas sampling sealing plug 420 and collects soil gas through the gas sampling tube 410, thus eliminating the need to remove the gas sampling sealing plug 420 and avoiding the exchange of soil gas with air, which would compromise the authenticity of the sample.

[0153] Example 8

[0154] This invention provides a gas collection method, applied to the soil gas collection device of any embodiment of this invention, thereby achieving all the technical effects brought about by the technical solutions of the above embodiments. The gas collection method includes:

[0155] S101: Place the gas collection device into the sampling hole of the sampling point;

[0156] It should be noted that before placing the gas collection device at the sampling point, a sampling hole must first be dug at the sampling point, including but not limited to using a twist drill or a Luoyang shovel to drill the hole. The depth and diameter of the sampling hole are set according to specific needs. The diameter of the sampling hole is slightly larger than the diameter of the gas collection container 10, and the depth of the sampling hole is less than the length of the gas collection container 10.

[0157] In some embodiments, placing the gas collection device inside the sampling hole of the sampling point includes:

[0158] The gap between the gas collection device and the sampling hole was filled with soil and compacted.

[0159] By filling and compacting the gap between the gas collection device and the sampling hole with soil, a seal is achieved, preventing air from the external environment from entering the gas collection container 10 through the gap and interfering with the soil gas sample.

[0160] S102: Inject exhaust water into the gas collection container 10 to vent the air inside the gas collection container 10;

[0161] In some embodiments, before injecting exhaust water into the gas collection container 10, the water injection sealing plug 320 and the sampling sealing plug are removed, and the air inlet valve 620 and the air outlet valve 720 are closed.

[0162] It should be noted that because a semi-permeable membrane 20 is provided at the bottom of the gas collection container 10, the exhaust water slowly passes through the semi-permeable membrane 20. The injection rate of the exhaust water is greater than the discharge rate of the exhaust water, so the water level in the gas collection container 10 gradually rises, purging the air in the gas collection container 10. This avoids air occupying the volume in the gas collection container 10, which would reduce the usable volume of soil gas and thus reduce the collectable volume of soil gas. It also avoids air mixing into the soil gas and interfering with the soil gas sample.

[0163] S103: Stop injecting exhaust water into the gas collection container 10;

[0164] In some embodiments, stopping the injection of exhaust water into the gas collection container 10 includes installing a water injection sealing plug 320 into the water injection pipe 310 and a gas collection sealing plug 420 into the gas collection pipe 410.

[0165] S104: Based on the gravity of the exhaust water, the exhaust water seeps into the soil around the gas collection device and discharges the soil gas.

[0166] S105: Collect the soil gas through the gas collection container 10.

[0167] It should be noted that, under the influence of gravity of the exhaust gas and the water absorption of the soil, the exhaust water slowly passes through the semi-permeable membrane 20 and seeps into the soil at the buried depth, forming a negative pressure. The gas collection container 10 draws in the soil gas at the buried depth, thereby obtaining soil gas at a fixed point and depth.

[0168] It should also be noted that the volume of soil gas collected is related to the volume of the gas collection container 10. The larger the gas collection container 10 is, the larger the volume of exhaust water injected into the gas collection container 10 will be, and the more exhaust water will seep into the soil. Therefore, the gas collection container 10 will absorb more soil gas.

[0169] In some embodiments, it also includes:

[0170] After a preset equilibration time, an external sampling device is used to collect soil gas through the gas sampling pipe 410 and transfer it into a transfer bottle.

[0171] It should be noted that when the target component cannot be detected on-site at the sampling point, soil gas can be extracted from the gas sampling tube 410 using a syringe, transferred to a transfer bottle, and then brought back to the laboratory for analysis.

[0172] In some embodiments, after a preset equilibration time, an external sampling device is used to collect soil gas through a gas sampling tube 410 and transfer it to a transfer bottle, including:

[0173] After a preset equilibrium time, if the air pressure above the semipermeable membrane 20 is less than the air pressure below the semipermeable membrane 20, then a preset volume of exhaust water is injected into the gas collection container 10.

[0174] The soil gas was collected using an external sampling device through the gas collection tube 410 and transferred to a transfer bottle.

[0175] By injecting the exhaust water from a pre-set container into the gas collecting container 10, a large volume of sample can be collected into the transfer bottle, providing sufficient sample volume for laboratory observation.

[0176] It should be noted that when the sampling volume is large, a negative pressure will be formed inside the gas collection container 10, which will prevent soil gas from entering the gas collection container 10. Therefore, the pre-filled exhaust water of the container is injected into the gas collection container 10 to increase the gas pressure inside the gas collection container 10, so that the soil gas can enter the gas collection container 10 smoothly.

[0177] It should also be noted that the preset volume is related to the sampling volume and the volume of the gas collection container 10.

[0178] Example 9

[0179] This invention provides a detection device, including a soil gas collection device according to any embodiment of this invention, thereby achieving all the technical effects brought about by the technical solutions of the above embodiments.

[0180] Example 10

[0181] The gas collection device of this invention is used to collect samples at sampling point A. The gas collection container 10 has a diameter of 6 cm and a length of 1.3 m. A sampling hole with a depth of 1.2 m is formed at sampling point A by drilling a hole with a diameter slightly larger than that of the gas collection container 10. Soil is filled and compacted to seal the gap between the gas collection container 10 and the sampling hole. The water injection sealing plug 320 and the gas collection sealing plug 420 are removed. The gas outlet valve 720 and the gas inlet valve 620 are closed. Exhaust gas is injected into the gas collection container 10 through the water injection pipe 310. Water is used to expel the air from the gas collection container 10. Water injection plugs 320 and gas collection plugs 420 are installed in the water injection pipe 310 and gas collection pipe 410 respectively to seal them. Due to gravity and soil water absorption, the vented water in the gas collection device slowly permeates through the semi-permeable membrane 20 into the soil, creating negative pressure, and the soil gas is drawn into the gas collection device. After 24 hours of equilibration, a 500ml soil gas sample is extracted from the gas collection pipe 410 by puncturing the gas collection plug 420 with a syringe and transferred to a transfer bottle for later analysis in the laboratory. Water is continuously injected through the injection port to collect samples; the maximum volume of soil gas sample that can be collected is equal to the volume of the gas collection container 10, which is 3675ml.

[0182] Light hydrocarbons in the samples were determined in the laboratory using a gas chromatograph with a flame hydrogen detector, and the contents of CO2, H2, He, and Ne were determined using a gas chromatograph with a thermal conductivity detector. The results are shown in Table 1.

[0183] Table 1. Gas component content in soil at sample point A (μL / L)

[0184] Sample number <![CDATA[CH4]]> <![CDATA[C2H6]]> <![CDATA[C2H4]]> <![CDATA[C3H8]]> <![CDATA[C3H6]]> <![CDATA[i-C4H 10 ]]> <![CDATA[n-C4H 10 ]]> <![CDATA[CO2]]> He Ne <![CDATA[H2]]> A 10.31 1.29 0.29 0.29 0.50 0.31 0.46 2277.5 5.09 17.53 130.3

[0185] Example 11

[0186] The gas collection device of this invention is used to collect samples at sampling point B. The gas collection container 10 has a diameter of 6 cm and a length of 1.3 m. A sampling hole with a depth of 1.2 m is formed at sampling point B by drilling a hole with a diameter slightly larger than that of the gas collection container 10. Soil is filled and compacted to seal the gap between the gas collection container 10 and the sampling hole. The water injection sealing plug 320 and the gas collection sealing plug 420 are removed. The gas outlet valve 720 and the gas inlet valve 620 are closed. Exhaust water is injected into the gas collection container 10 through the water injection pipe 310 to collect the gas. The air inside container 10 is emptied, and water injection sealing plugs 320 and gas collection sealing plugs 420 are installed in water injection pipe 310 and gas collection pipe 410 respectively to seal them. The exhaust water in the gas collection device slowly seeps into the soil through semi-permeable membrane 20 due to gravity and soil water absorption, forming a negative pressure. The soil gas is drawn into the gas collection device. After 24 hours of equilibration, the gas analyzer 50 is connected, and the inlet valve 620 and outlet valve 720 are opened to conduct on-site internal gas circulation measurement and continuous, dynamic, and real-time monitoring. The test results are shown in Table 2.

[0187] Table 2B shows the content (μL / L) of gas components in the soil from continuous detection.

[0188]

[0189]

[0190] Example 12

[0191] The gas collection device of this invention is used to collect samples at sampling point C. The gas collection container 10 has a diameter of 6 cm and a length of 1.3 m. A sampling hole with a depth of 1.2 m is formed at sampling point C by drilling a hole with a diameter slightly larger than that of the gas collection container 10. Soil is filled and compacted to seal the gap between the gas collection container 10 and the sampling hole. The water injection sealing plug 320 and the gas sampling sealing plug 420 are removed. The gas outlet valve 720 and the gas inlet valve 620 are closed. Exhaust water is injected into the gas collection container 10 through the water injection pipe 310 to fill the gas collection container. The air inside the device 10 is purged, and water injection sealing plugs 320 and gas collection sealing plugs 420 are installed in the water injection pipe 310 and gas collection pipe 410 respectively to seal them. The exhaust water in the gas collection device slowly seeps into the soil through the semi-permeable membrane 20 due to gravity and soil water absorption, forming a negative pressure. The soil gas is drawn into the gas collection device. After 24 hours of equilibration, the gas analyzer 50 is connected, the inlet valve 620 is opened and the outlet valve 720 is closed to conduct on-site internal gas circulation measurement and continuous, dynamic and real-time monitoring. The test results are shown in Table 3.

[0192] Table 3. Gas component content in soil at sample point C (μL / L)

[0193] Sample number <![CDATA[CH4]]> <![CDATA[CO2]]> C 3.056 2225

[0194] As can be seen from the above, the gas collection device provided by this invention can collect soil gas, enabling not only large-volume sampling and return to the laboratory for target component detection, but also continuous, dynamic, and real-time on-site detection or monitoring. It reduces air interference, ensures the collection of soil gas samples, reduces errors, and accurately obtains target components, thus guaranteeing the acquisition of accurate and effective data.

[0195] Comparative Example 1

[0196] Existing Chinese patent CN101236141A discloses a geogas sampling auger, which belongs to the same field of drilling tools as this invention. This geogas sampling auger includes components such as a conical drill bit body, a capped auger rod, a drill rod, and a handle, and is a manual soil gas sampling device.

[0197] To illustrate the accuracy and effectiveness of the gas collection device and method of the present invention, a ground gas collection auger is used as a comparative example for comparison.

[0198] Specifically, the ground gas sampling auger disclosed in CN101236141A was used to collect gas samples at the same sampling points as in Example 10 above. The contents of light hydrocarbons, carbon dioxide, and helium-neon hydrogen in the collected samples were determined using a gas chromatograph with the same flame ionization detector and thermal conductivity detector as in Example 10 above, and the results are shown in Table 4.

[0199] Table 4. Soil gas component content (μL / L) collected by a geothermal sampling auger at sampling point A.

[0200] Sample number <![CDATA[CH4]]> <![CDATA[C2H6]]> <![CDATA[C2H4]]> <![CDATA[C3H8]]> <![CDATA[C3H6]]> <![CDATA[i-C4H 10 ]]> <![CDATA[n-C4H 10 ]]> <![CDATA[CO2]]> He Ne <![CDATA[H2]]> A 8.22 0.93 0.14 0.16 0.35 0.17 0.23 2086.4 5.07 17.32 105.9

[0201] By comparing Table 1 of Example 10 and Table 4 of the comparative example, it can be seen that when gas samples were collected using the existing ground gas sampling auger, and air samples were analyzed at each sampling point, the methane content was approximately 2 μL / L, the carbon dioxide content was approximately 400 μL / L, and the helium, neon, and hydrogen contents were approximately 5 μL / L, 17 μL / L, and 1 μL / L, respectively. The comparison revealed that air was mixed into the samples collected using the existing technology, resulting in a decrease in the content of light hydrocarbons, carbon dioxide, and hydrogen compared to the gas samples collected using the device and method of the present invention. However, the helium and neon contents were comparable to those of air, and their content was essentially unaffected. This proves that the gas samples collected using the gas collection device and method of the present invention do not contain mixed air, meaning that the soil gas obtained using the high-fidelity gas collection device and method of the present invention is genuine and effective soil gas. Furthermore, the maximum collectable volume of the gas sample at point A collected using the existing ground gas sampling auger is 6.4 mL, which is significantly less than the amount of gas sample collected using the high-fidelity gas collection device and method of the present invention. Therefore, the gas collection device and method of the present invention can obtain a larger amount of gas samples, and their efficiency and practicality are greatly improved.

[0202] In summary, the gas collection device and method of this invention utilize liquid displacement to expel residual air from the channel. The liquid leakage creates negative pressure, drawing in soil gas. Once equilibrium is reached, the collection and transfer of soil gas is completed. This process avoids air interference, ensuring accurate soil gas collection without loss. The collected sample volume is large enough to meet instrumental analysis needs, laying the foundation for obtaining accurate and effective target gas components and thus for effectively tracking and predicting underlying oil and gas reservoirs, other gas reservoirs, and geothermal resources.

[0203] Although the invention has been described with reference to preferred embodiments, various modifications can be made and components can be replaced with equivalents without departing from the scope of the invention. In particular, the technical features mentioned in the various embodiments can be combined in any manner as long as there is no structural conflict. The invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A soil gas collection device, characterized in that, include: A gas collecting container, wherein the upper end of the gas collecting container is closed and the lower end is open; A semi-permeable membrane is disposed at the opening; The semi-permeable membrane allows gas to pass through without obstruction and allows water to pass through slowly. A water injection assembly, disposed at the upper end of the gas collecting container, is used to inject exhaust water into the gas collecting container, the exhaust water slowly passing through the semi-permeable membrane; and A gas sampling assembly is disposed at the upper end of the gas collection container, and the gas sampling assembly is used for gas outflow.

2. The soil gas collection device according to claim 1, characterized in that, The water injection assembly includes a water injection pipe and a water injection sealing plug disposed on the water injection pipe; the gas extraction assembly includes a gas extraction pipe and a gas extraction sealing plug disposed on the gas extraction pipe.

3. The soil gas collection device according to claim 1, characterized in that, The gas collection device also includes: Analyzer; The air intake assembly is connected at one end to the air inlet of the analyzer and at the other end to the gas collection container. The gas outlet assembly is connected at one end to the gas outlet of the analyzer and at the other end to the gas collection container.

4. The soil gas collection device according to claim 3, characterized in that, The air intake assembly includes an air intake pipe and an air intake valve disposed on the air intake pipe; the air outlet assembly includes an air outlet pipe and an air outlet valve disposed on the air outlet assembly; wherein, the length of the air intake pipe extending into the air collection container is greater than the length of the air outlet pipe extending into the air collection container.

5. The soil gas collection device according to claim 4, characterized in that, The length of the air intake pipe extending into the air collection container is greater than half the length of the air collection container.

6. A gas collection method, characterized in that, The soil gas collection device as described in any one of claims 1-5 comprises: Place the gas collection device inside the sampling hole at the sampling point; Inject exhaust water into the gas collection container to purge the air from the gas collection container; Stop injecting the exhaust water into the gas collection container; Based on the gravity of the exhaust water, the exhaust water seeps into the soil around the gas collection device and discharges the soil gas. The soil gas is collected through the gas collection container.

7. The gas collection method according to claim 6, characterized in that, Also includes: After a preset balancing time, open the inlet valve and outlet valve, or open the inlet valve to connect the gas collection container to the analyzer; The soil gas is detected using the analyzer.

8. The gas collection method according to claim 6, characterized in that, Also includes: After a preset equilibration time, an external sampling device is used to collect the soil gas through a gas sampling tube and transfer it into a transfer bottle.

9. The gas collection method according to claim 8, characterized in that, After a preset equilibration time, the process of using an external sampling device to collect soil gas through a gas sampling tube and transferring it to a transfer bottle includes: After a preset equilibrium time, if the air pressure above the semipermeable membrane is less than the air pressure below the semipermeable membrane, then a preset volume of the exhaust water is injected into the gas collection container. The soil gas is collected using an external sampling device through a gas collection tube and transferred to the transfer bottle.

10. A detection system, characterized in that, It includes the soil gas collection device as described in any one of claims 1-5.

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