Portable deep soil gas sampling device

Abstract

The invention provides a portable deep soil gas sampling device, which comprises: a filter assembly, which comprises a filter pipe and a screen cover; an air inlet of the sampling bag is connected with the bottom of the filter pipe; the piston assembly comprises an exhaust pipe, a piston capable of moving in the exhaust pipe and an elastic piece connected with the piston, and an exhaust hole is formed in the exhaust pipe; the control assembly comprises a limiting component and a driving component, and the limiting component fixes the piston in an initial state; when the driving part drives the limiting part to move, the piston is released, and the reset force of the elastic part drives the piston to move in the exhaust pipe, so that gas in the exhaust pipe is exhausted from the exhaust hole, the air pressure in the filter pipe connected with the exhaust pipe is reduced, and soil gas is promoted to flow into the filter pipe through the screen cover and enter the sampling bag through the air inlet; and sampling is completed. The portable deep soil gas sampling device provided by the invention solves the technical problems of high cost, complex operation and poor sampling flexibility of sampling equipment in related technologies.

Description

Technical Field

[0001] The invention relates to the technical field of soil gas sampling, and in particular to a portable deep soil gas sampling device. Background Art

[0002] Soil gas sampling is a key step in the remediation of contaminated sites and environmental monitoring. It can provide important information about the composition and content of soil gas, which helps to assess the status of soil pollution and guide the remediation of contaminated sites. In the existing technology, there are two common soil gas sampling methods: monitoring well sampling method and automatic sampling device.

[0003] Monitoring well sampling is a traditional soil gas sampling method. Monitoring wells are built on site and gas sampling equipment is inserted deep into the soil to collect samples. Although this method can obtain deep soil gas, it has some significant shortcomings: First, the cost of building monitoring wells is high and the construction time is long, which limits its application in large areas. Second, the sampling process is easily affected by the external environment, which affects the accuracy of soil gas samples. In addition, the sampling efficiency of monitoring wells is low and it is difficult to adapt to the needs of fast and multi-point sampling.

[0004] The automatic sampling device completes soil gas sampling through a combination of a gas extraction device, a filtering device and a storage device. The gas extraction device is responsible for extracting gas from the soil, the filtering device removes impurities, and the storage device is used to store the filtered gas. This device improves the sampling efficiency and accuracy to a certain extent. However, there are still some problems with the existing automatic sampling devices. First, they have a complex structure and high manufacturing cost, which are not suitable for large-scale promotion. Secondly, the filtering device is unstable in actual use, and incomplete filtration often occurs, resulting in impurities in the collected soil gas samples, affecting the accuracy of the test results. In addition, during the gas storage process, the existing devices are prone to gas leakage, resulting in sample loss. Finally, these devices are not flexible enough in adjusting the sampling depth and position, and it is difficult to meet the diverse needs under different environmental conditions.

[0005] Therefore, the prior art needs to be further developed. Summary of the invention

[0006] The purpose of the present invention is to overcome the above technical deficiencies and provide a portable deep soil gas sampling device to solve the technical problems of high sampling equipment cost, complex operation and poor sampling flexibility in the related art.

[0007] In order to achieve the above technical objectives, the present invention adopts the following technical solutions: a portable deep soil gas sampling device is provided, comprising: a filter assembly, comprising a filter tube and a screen cover, the screen cover is arranged on the top of the filter tube, and is used to filter soil impurities; a sampling bag, the air inlet of the sampling bag is connected to the bottom of the filter tube, and is used to collect filtered soil gas; a piston assembly, comprising an exhaust pipe, a piston movable in the exhaust pipe, and an elastic member connected to the piston, and an exhaust hole is arranged on the exhaust pipe; a control assembly, comprising a limiting component and a driving component, and the limiting component fixes the piston in an initial state; when the driving component drives the limiting component to move, the piston is released, and the restoring force of the elastic member drives the piston to move in the exhaust pipe, so that the gas in the exhaust pipe is discharged from the exhaust hole, resulting in a decrease in the air pressure in the filter tube connected to the exhaust pipe, thereby prompting the soil gas to flow into the filter tube through the screen cover, and enter the sampling bag through the air inlet to complete the sampling.

[0008] Furthermore, the filter assembly also includes a conical joint, and a first interface and a second interface are respectively arranged at both ends of the conical joint, the first interface is arranged around the inner wall of the filter tube, the diameter of the second interface is smaller than the diameter of the first interface, the air inlet is connected to the second interface, and the sampling bag is located between the conical joint and the piston assembly.

[0009] Furthermore, a screen is provided on the first interface, and the filter assembly also includes hydrophobic cotton and a filter membrane. The filter membrane is located on the side of the screen close to the screen cover, the hydrophobic cotton is located between the screen cover and the filter membrane, and the screen is used to support the hydrophobic cotton and the filter membrane; soil gas first enters the filter tube through the screen cover, and after filtering fine soil particles through the hydrophobic cotton, it enters the air inlet from the second interface through the filter membrane.

[0010] Furthermore, a one-way valve is provided on the sampling bag, and the one-way valve is located at the lower end of the air inlet, so that the gas only enters the sampling bag from the air inlet.

[0011] Furthermore, an air extraction port is provided at one end of the sampling bag away from the air inlet to facilitate air extraction after sampling is completed.

[0012] Furthermore, the elastic member is a first spring, one end of which is fixed to the bottom of the exhaust pipe, and the other end is connected to the piston, and the limiting component and the first spring are both located on the same side of the piston; in an initial state, the first spring is in a stretched state, the piston is clamped on the limiting component, and the driving component is fixed to the outside of the exhaust pipe for controlling the movement of the limiting component.

[0013] Furthermore, the driving component is a mechanical timer, a second spring is arranged in the mechanical timer, the limiting component is a card plate, one end of the second spring is fixed in the mechanical timer, and the other end is connected to the card plate; in the initial state, the card plate is pressed by turning the mainspring, so that the card plate passes through the side wall of the exhaust pipe and enters the interior to clamp the piston, and the second spring is stretched at this time; when the mechanical timer runs to a preset time, the card plate loses the pressing force of the mainspring, the second spring resets, and drives the card plate to move out of the exhaust pipe, thereby releasing the piston.

[0014] Further, the cone joint is threadably connected to the sampling bag.

[0015] Furthermore, the filter tube is threadedly connected to the exhaust pipe.

[0016] Furthermore, the sampling device also includes a pull ring, which is connected to the filter tube and is used to hang the sampling device.

[0017] Beneficial effects:

[0018] 1. The portable deep soil gas sampling device of the present invention has a compact design, simple structure, convenient operation, and is easy to carry. It is particularly suitable for multi-point soil gas sampling in different environments, overcoming the problems of bulky equipment and high cost in the prior art.

[0019] 2. The portable deep soil gas sampling device of the present invention can effectively reduce the air pressure in the filter tube through the cooperation of the piston assembly and the elastic member, thereby prompting the deep soil gas to flow into the sampling bag, thereby achieving efficient deep gas sampling.

[0020] 3. The portable deep soil gas sampling device of the present invention adopts a mechanical timer as a driving component, and realizes the operation of automatically releasing the piston through the cooperation of the clamping plate and the spring, thereby reducing manual intervention, reducing the complexity of operation, and ensuring the automation and accuracy of the sampling process.

[0021] 4. The portable deep soil gas sampling device of the present invention has a sampling bag, a filter tube and an exhaust pipe connected by threads, and can be quickly assembled and disassembled according to different sampling environments, with strong flexibility; in addition, by using a pull ring and a rope in combination, it can adapt to sampling needs at different depths and positions, and realizes flexible adjustment of the sampling depth and sampling position. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is a schematic structural diagram of a portable deep soil gas sampling device used in an embodiment of the present invention;

[0023] Figure 2 is a schematic diagram of the structure of the filter assembly used in the embodiment of the present invention;

[0024] Figure 3Schematic diagram of the structure of the sampling bag used in the embodiment of the present invention;

[0025] Figure 4 This is a schematic diagram of the use state of the limiting component retracted in the first embodiment of the present invention;

[0026] Figure 5 is a schematic diagram of the structure of the control component used in the first embodiment of the present invention;

[0027] Figure 6 It is a schematic diagram of the structure of the control component used in the second embodiment of the present invention.

[0028] The above drawings include the following reference numerals:

[0029] 1. Filter assembly; 11. Filter tube; 12. Screen cover; 13. Conical joint; 131. First interface; 132. Second interface; 133. Screen; 14. Hydrophobic cotton; 15. Filter membrane; 2. Sampling bag; 21. Air inlet; 22. One-way valve; 23. Air outlet; 3. Piston assembly; 31. Exhaust pipe; 311. Exhaust hole; 32. Piston; 33. Elastic member; 331. First spring; 4. Control assembly; 41. Limiting component; 411. Card plate; 412. Rack; 42. Driving component; 421. Mechanical timer; 422. Second spring; 423. Micro motor; 43. Gear; 44. Sleeve rod; 45. Fixed seat; 46. Limiting rod; 5. Pull ring. DETAILED DESCRIPTION

[0030] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present application.

[0031] According to an embodiment of the present invention, a portable deep soil gas sampling device is provided. Figures 1 to 6, including: a filter assembly 1, including a filter tube 11 and a screen cover 12, the screen cover 12 is set on the top of the filter tube 11, and is used to filter soil impurities; a sampling bag 2, the air inlet 21 of the sampling bag 2 is connected to the bottom of the filter tube 11, and is used to collect filtered soil gas; a piston assembly 3, including an exhaust pipe 31, a piston 32 that can move in the exhaust pipe 31, and an elastic member 33 connected to the piston 32, and the exhaust pipe 31 is provided with an exhaust hole 311; a control assembly 4, including a limit component 41 and the driving component 42, the limiting component 41 fixes the piston 32 in the initial state; when the driving component 42 drives the limiting component 41 to move, the piston 32 is released, and the restoring force of the elastic component 33 drives the piston 32 to move in the exhaust pipe 31, so that the gas in the exhaust pipe 31 is discharged from the exhaust hole 311, resulting in a decrease in the air pressure in the filter tube 11 connected to the exhaust pipe 31, thereby prompting the soil gas to flow into the filter tube 11 through the screen cover 12, and enter the sampling bag 2 through the air inlet 21, thereby completing the sampling.

[0032] The gas collection process of the portable deep soil gas sampling device of this embodiment is as follows: when the driving component 42 drives the limiting component 41 to move, the limiting component releases the fixed piston 32, and the elastic member 33 begins to reset, driving the piston 32 to move in the exhaust pipe 31. The movement of the piston 32 causes the gas in the exhaust pipe 31 to be discharged through the exhaust hole 311, and the air pressure in the exhaust pipe 31 is reduced, which in turn causes the air pressure in the filter tube 11 connected to the exhaust pipe 31 to be reduced, forming a negative pressure. As the air pressure in the filter tube 11 decreases, the gas in the soil is sucked in and passes through the mesh cover 12 located at the top of the filter tube 11, while filtering out impurities in the soil. The soil gas filtered by the mesh cover 12 continues to flow downward along the filter tube 11, and finally enters the sampling bag 2 through the air inlet 21 for collection, completing the entire soil gas sampling process. The piston assembly 3 is controlled to move by the control component 4, forming an air pressure difference in the exhaust pipe 31, prompting the external soil gas to enter the sampling bag 2 through the filter assembly 1, and automatically completing the collection of deep soil gas. The sampling device of this embodiment has a compact structure, simple design, and is easy to use. It is particularly suitable for sampling soil gas in various environments. Compared with the traditional monitoring well sampling method, the operation is simpler and does not require complex equipment, which greatly reduces the sampling difficulty, operation cost, and maintenance cost. In addition, the device is small in size, light in weight, and easy to carry. It is suitable for soil gas sampling in the field and under complex terrain conditions, and is particularly suitable for environmental monitoring of contaminated sites. The portable deep soil gas sampling device of this embodiment solves the technical problems of high sampling equipment cost, complex operation, and poor sampling flexibility in the related art.

[0033] See also Figure 1 and Figure 2In the portable deep soil gas sampling device of this embodiment, the filter assembly 1 also includes a cone joint 13, and the two ends of the cone joint 13 are respectively provided with a first interface 131 and a second interface 132, the first interface 131 is provided around the inner wall of the filter tube 11, the diameter of the second interface 132 is smaller than the diameter of the first interface 131, the air inlet 21 is connected to the second interface 132, and the sampling bag 2 is located between the cone joint 13 and the piston assembly 3. The design of the cone joint 13 makes the gas flow path more orderly, and the diameter difference between the first interface 131 and the second interface 132 can effectively guide the gas to flow into the sampling bag 2. Such a design optimizes the airflow path, reduces the resistance of gas flow, and improves the sampling efficiency.

[0034] See also Figure 2 In the portable deep soil gas sampling device of this embodiment, a screen 133 is provided on the first interface 131, and the filter assembly 1 further includes a hydrophobic cotton 14 and a filter membrane 15. The filter membrane 15 is located on the side of the screen 133 close to the screen cover 12, and the hydrophobic cotton 14 is located between the screen cover 12 and the filter membrane 15. The screen 133 is used to support the hydrophobic cotton 14 and the filter membrane 15; the soil gas first enters the filter tube 11 through the screen cover 12, and after the hydrophobic cotton 14 filters the fine soil particles, it enters the air inlet 21 from the second interface 132 through the filter membrane 15. The hydrophobic cotton 14 does not absorb pollutants, and the combined design of the screen cover 12, the hydrophobic cotton 14, and the filter membrane 15 can effectively filter impurities, particles and moisture of different sizes. The screen cover 12 first filters out larger impurities, the hydrophobic cotton 14 further filters fine particles and removes excess water, and the filter membrane 15 finely filters the gas, and finally the metal screen 133 supports the gas to smoothly enter the sampling bag 2. Multi-level filtration ensures the purity of the soil gas sample and improves the accuracy of the test results.

[0035] See also Figure 1 and Figure 3 In the portable deep soil gas sampling device of this embodiment, a one-way valve 22 is also provided on the sampling bag 2. The one-way valve 22 is located at the lower end of the air inlet 21, so that the gas only enters the sampling bag 2 from the air inlet 21, effectively preventing the gas backflow, and ensuring that the soil gas sample will not be contaminated or the sample amount will be reduced due to gas backflow during the collection process, thereby improving the accuracy of the sample.

[0036] See also Figure 1 and Figure 3 In the portable deep soil gas sampling device of this embodiment, a gas extraction port 23 is provided at one end of the sampling bag 2 away from the gas inlet 21, so as to facilitate gas extraction after sampling. The gas extraction port 23 is provided so that after sampling, the operator can easily take out the gas sample through the port without moving or turning over the entire sampling bag, thereby simplifying the sampling process and improving the operating efficiency.

[0037] See also Figure 1 and Figure 4 In the portable deep soil gas sampling device of this embodiment, the elastic member 33 is a first spring 331, one end of the first spring 331 is fixed to the bottom of the exhaust pipe 31, and the other end is connected to the piston 32. The limiting component 41 and the first spring 331 are both located on the same side of the piston 32; in the initial state, the first spring 331 is in a stretched state, the piston 32 is clamped on the limiting component 41, and the driving component 42 is fixed on the outside of the exhaust pipe 31 to control the movement of the limiting component 41. Through the control of the driving component 42, when the piston 32 is released, the reset force of the first spring 331 drives the piston 32 to automatically complete the gas discharge process, so that a pressure difference is formed in the filter tube 11, prompting the gas to flow from the outside into the filter tube 11, and enter the sampling bag 2 through the air inlet 21. Since the first spring 331 is in a stretched state in the initial state, once the piston 32 is released, the first spring 331 will immediately reset and drive the piston 32 to move quickly, forming a gas pressure difference, thereby prompting the gas to quickly enter the sampling bag 2. The entire process requires no manual operation and is completed automatically, which improves sampling efficiency.

[0038] See also Figure 4 and Figure 5In the portable deep soil gas sampling device of this embodiment, the driving component 42 is a mechanical timer 421, a second spring 422 is arranged in the mechanical timer 421, and the limiting component 41 is a cardboard 411, one end of the second spring 422 is fixed in the mechanical timer 421, and the other end is connected to the cardboard 411; in the initial state, the cardboard 411 is pressed by turning the spring, so that the cardboard 411 passes through the side wall of the exhaust pipe 31 and enters the inside thereof to clamp the piston 32, and at this time the second spring 422 is stretched; when the mechanical timer 421 runs to the preset time, the cardboard 411 loses the pressing force of the spring, and the second spring 422 is reset, driving the cardboard 411 to move out of the exhaust pipe 31, thereby releasing the piston 32. Before the device is ready for use, the operator first turns the spring on the mechanical timer 421, and this operation stretches the second spring 422 inside the timer to store elastic potential energy. At the same time, the clamping plate 411 is pressed from the side wall of the exhaust pipe 31 into the exhaust pipe 31, passes through the side wall and clamps the piston 32 to prevent it from moving. In this state, the piston 32 is locked in the initial position, and the first spring 331 remains in a stretched state. When the mechanical timer 421 starts to run, the spring gradually releases the stored energy, and the timer accurately counts according to the preset time. In this timing stage, the clamping plate 411 remains in a pressed state, and the piston 32 is still fixed in the exhaust pipe 31. When the mechanical timer 421 runs to the preset time, the pressure of the spring gradually weakens, and the second spring 422 in the timer begins to reset and restores its original state. The reset force of the second spring 422 drives the clamping plate 411 to move out of the side wall of the exhaust pipe 31, releasing the fixation of the piston 32. Once the clamping plate 411 is moved out, the first spring 331 begins to reset quickly, driving the piston 32 to move downward in the exhaust pipe 31. The movement of the piston 32 causes the gas in the exhaust pipe 31 to be discharged through the exhaust hole 311, generating negative pressure, thereby reducing the air pressure in the filter tube 11 connected to the exhaust pipe 31. As the air pressure in the filter tube 11 decreases, the gas in the deep soil is sucked in, enters the filter tube 11 through the screen cover 12, passes through multiple layers of filtration (such as hydrophobic cotton, filter membrane, etc.), and finally enters the sampling bag 2 through the second interface 132 and the air inlet 21 to complete the gas sampling. Through the mechanical timer 421, the sampling process can be automatically triggered at a set time point, reducing the error and burden of manual operation, low cost of use, and ensuring accurate and stable sampling.

[0039] See also Figure 6In the portable deep soil gas sampling device of this embodiment, the driving component 42 is a micro motor 423, the limiting component 41 is a rack 412, the control component 4 also includes a gear 43 and a sleeve rod 44, the sleeve rod 44 and the micro motor 423 are both fixed in a fixed seat 45 connected to the exhaust pipe 31, the sleeve rod 44 is sleeved on the rack 412, the rack 412 is movable relative to the sleeve rod 44, the output end of the micro motor 423 is connected to the gear 43, and the rack 412 is provided with a tooth groove meshing with the gear 43; when the micro motor 423 drives the gear 43 to rotate, the gear 43 drives the rack 412 to move, so that the rack 412 extends into or moves out of the exhaust pipe 31, thereby engaging or releasing the piston 32. A limiting rod 46 is provided on the side of the rack 412 away from the gear 43, and the limiting rod 46 is used to limit the moving range of the rack 412. When the device is in the initial state, the rack 412 is controlled by the micro motor 423 to be in the extended state, and the rack 412 passes through the side wall of the exhaust pipe 31 to firmly clamp the piston 32 in the exhaust pipe 31. The first spring 331 is in a stretched state at this time, accumulating elastic potential energy for reset, waiting for clamping release. When the piston 32 needs to be released for sampling, the device starts the micro motor 423, and the output shaft of the micro motor drives the gear 43 connected thereto to start rotating. The rotation of the gear 43 is engaged with the tooth groove on the rack 412, driving the rack 412 to move along the direction of the sleeve rod 44. As the gear 43 rotates, the rack 412 is pushed by the gear 43 and gradually moves out of the side wall of the exhaust pipe 31. When the rack 412 is completely moved out of the exhaust pipe 31, the piston 32 loses its fixation and the clamping is released. When the piston 32 is released, the first spring 331 begins to reset, pushing the piston 32 to move downward along the exhaust pipe 31, pushing the gas in the exhaust pipe 31 to be discharged through the exhaust hole 311, thereby causing the air pressure in the exhaust pipe 31 to decrease. Since the exhaust pipe 31 is connected to the filter tube 11, the air pressure in the filter tube 11 also decreases, forming a negative pressure. Under the action of the negative pressure, the gas in the deep soil is sucked in, and the gas enters the sampling bag 2 through the air inlet 21, completing the gas sampling. After the sampling is completed, the micromotor 423 can reversely drive the gear 43 to rotate again, push the rack 412 to extend into the exhaust pipe 31 again, re-engage the piston 32 in its position, complete the reset of the device, and prepare for the next sampling operation. The micromotor has low energy consumption and simple operation, and can easily realize the automated operation of sampling, reduce the energy consumption of the device, and reduce the need for complex manual operation.

[0040] See also Figure 1 and Figure 2 In the portable deep soil gas sampling device of this embodiment, the cone joint 13 is threadedly connected to the sampling bag 2 to facilitate installation and disassembly, which simplifies the sampling operation process and improves the convenience of operation, allowing the operator to complete the sampling task more quickly.

[0041] See also Figure 1and Figure 2 In the portable deep soil gas sampling device of this embodiment, the filter tube 11 is threadedly connected with the exhaust pipe 31, making installation and disassembly simple and quick.

[0042] See also Figure 1 and Figure 2 The portable deep soil gas sampling device of this embodiment further comprises a pull ring 5, which is connected to the filter tube 11 and is used to hang the sampling device. The pull ring 5 can hang a rope, so that the sampling device can be easily lowered into the borehole of the deep soil, which greatly improves the sampling ability of the sampling device for the deep soil, and enables the operator to obtain soil gas samples that are deeper and more difficult to reach. By precisely controlling the length of the rope and the hanging position of the pull ring 5, the operator can accurately locate the depth of the sampling device in the borehole. This precise control helps to ensure that each sampling can be carried out at the target depth, thereby improving the accuracy and representativeness of the sampling.

[0043] The portable deep soil gas sampling device of the present invention has a threaded connection design between the filter tube and the exhaust pipe, which further enhances the sealing of the filtration system and effectively prevents gas leakage during the filtration process, thereby ensuring the purity and quality of the gas. Compared with the prior art, there is no need to build expensive monitoring wells, and the use of pull rings and ropes for hanging sampling reduces the sampling cost. At the same time, the device is small and light, easy to carry and operate, and improves the sampling efficiency. In addition, the device can sample deep into the soil, reduce the influence of surface interference factors, improve the accuracy of sampling, and realize flexible adjustment of the sampling depth and sampling position. The operator can easily adjust the length of the rope and the position of the pull ring according to actual needs, so as to accurately control the depth and position of the sampling device in the soil. This design enables the sampling device to adapt to the sampling needs under different environmental conditions, and improves the flexibility and practicality of sampling.

[0044] The present invention can be widely used in application fields such as soil remediation science and environmental monitoring. First, in the field of soil remediation science, the present invention provides an efficient and accurate soil gas sampling method, which can greatly improve the efficiency and accuracy of sampling, reduce the influence of artificial factors, and improve the research efficiency and quality of soil gas. At the same time, the present invention can also realize the accurate sampling of soil gas at different depths and different positions, meet the sampling needs under different environmental conditions, and help to deeply understand the gas composition and content in the soil, which is of great significance for the research and application of soil remediation science. In the field of environmental monitoring, the present invention provides an efficient and accurate soil gas monitoring method, which can monitor the gas composition and content in the soil in real time, and timely reflect the health status of the soil and the degree of environmental pollution, which is of great significance for environmental protection and governance. At the same time, the present invention can also realize the accurate monitoring of soil gas at different depths and different positions, meet the monitoring needs under different environmental conditions, and help to improve the efficiency and quality of environmental monitoring.

[0045] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0046] Optionally, the specific examples in this embodiment may refer to the examples described in the above embodiments, and this embodiment will not be described in detail here.

[0047] The serial numbers of the above-mentioned embodiments of the present application are for description only and do not represent the advantages or disadvantages of the embodiments.

[0048] In the above embodiments of the present application, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, please refer to the relevant description of other embodiments.

[0049] The above is only a preferred implementation of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A portable deep soil gas sampling device, characterized in that: include: A filter assembly (1) comprises a filter tube (11) and a screen cover (12), wherein the screen cover (12) is arranged on the top of the filter tube (11) and is used to filter soil impurities; A sampling bag (2), wherein the air inlet (21) of the sampling bag (2) is connected to the bottom of the filter tube (11) and is used to collect filtered soil gas; A piston assembly (3) comprises an exhaust pipe (31), a piston (32) movable in the exhaust pipe (31), and an elastic member (33) connected to the piston (32), wherein the exhaust pipe (31) is provided with an exhaust hole (311); The control component (4) comprises a limiting component (41) and a driving component (42), wherein the limiting component (41) fixes the piston (32) in an initial state; when the driving component (42) drives the limiting component (41) to move, the piston (32) is released, and the restoring force of the elastic component (33) drives the piston (32) to move in the exhaust pipe (31), so that the gas in the exhaust pipe (31) is discharged from the exhaust hole (311), resulting in a decrease in the air pressure in the filter pipe (11) connected to the exhaust pipe (31), thereby causing the soil gas to flow into the filter pipe (11) through the screen cover (12) and enter the sampling bag (2) through the air inlet (21), thereby completing the sampling.

2. The portable deep soil gas sampling device according to claim 1, characterized in that: The filter assembly (1) further comprises a conical joint (13), wherein a first interface (131) and a second interface (132) are respectively arranged at two ends of the conical joint (13), wherein the first interface (131) is arranged around the inner wall of the filter tube (11), and the diameter of the second interface (132) is smaller than the diameter of the first interface (131), the air inlet (21) is connected to the second interface (132), and the sampling bag (2) is located between the conical joint (13) and the piston assembly (3).

3. The portable deep soil gas sampling device according to claim 2, characterized in that: A screen (133) is provided on the first interface (131), and the filter assembly (1) further comprises hydrophobic cotton (14) and a filter membrane (15), wherein the filter membrane (15) is located on a side of the screen (133) close to the screen cover (12), the hydrophobic cotton (14) is located between the screen cover (12) and the filter membrane (15), and the screen (133) is used to support the hydrophobic cotton (14) and the filter membrane (15); soil gas first enters the filter tube (11) through the screen cover (12), and after filtering fine soil particles through the hydrophobic cotton (14), enters the air inlet (21) from the second interface (132) through the filter membrane (15).

4. The portable deep soil gas sampling device according to claim 1, characterized in that: The sampling bag (2) is also provided with a one-way valve (22), which is located at the lower end of the air inlet (21) so that gas can enter the sampling bag (2) only from the air inlet (21).

5. The portable deep soil gas sampling device according to claim 4, characterized in that: An air extraction port (23) is provided at one end of the sampling bag (2) away from the air inlet (21) to facilitate air extraction after sampling is completed.

6. The portable deep soil gas sampling device according to claim 1, characterized in that: The elastic member (33) is a first spring (331), one end of the first spring (331) is fixed to the bottom of the exhaust pipe (31), and the other end is connected to the piston (32), and the limiting component (41) and the first spring (331) are both located on the same side of the piston (32); in an initial state, the first spring (331) is in a stretched state, the piston (32) is clamped on the limiting component (41), and the driving component (42) is fixed to the outside of the exhaust pipe (31) and is used to control the movement of the limiting component (41).

7. The portable deep soil gas sampling device according to claim 6, characterized in that: The driving component (42) is a mechanical timer (421), a second spring (422) is arranged inside the mechanical timer (421), the limiting component (41) is a card plate (411), one end of the second spring (422) is fixed inside the mechanical timer (421), and the other end is connected to the card plate (411); In the initial state, the spring is turned to press the clamping plate (411), so that the clamping plate (411) passes through the side wall of the exhaust pipe (31) and enters the interior thereof to clamp the piston (32), and at this time, the second spring (422) is stretched; when the mechanical timer (421) runs to a preset time, the clamping plate (411) loses the pressing force of the spring, and the second spring (422) is reset, driving the clamping plate (411) to move out of the exhaust pipe (31), thereby releasing the piston (32).

8. The portable deep soil gas sampling device according to claim 2, characterized in that: The cone joint (13) is threadably connected to the sampling bag (2).

9. The portable deep soil gas sampling device according to claim 1, characterized in that: The filter tube (11) is threadably connected to the exhaust pipe (31).

10. The portable deep soil gas sampling device according to claim 1, characterized in that: The sampling device further comprises a pull ring (5), wherein the pull ring (5) is connected to the filter tube (11) and is used for hanging the sampling device.

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