Collecting device for greenhouse gases in different soil depths

Abstract

The utility model discloses a collection device for greenhouse gases in different soil depths. The collection device is composed of a top end device, a sampling well, a sampling pipe, a top sealing rubber ring, a sampling rubber ring, a sampling cavity, a sealing rubber ring and a gas collection chamber. The sampling rubber ring can be aligned with the latex tubes with different depths by pulling the sampling tube, so that the purpose of collecting greenhouse gases in soil with different depths is achieved. Materials used by the whole device are low in price, and the device is suitable for long-term collection or continuous automatic monitoring of soil gas at different depths, convenient, efficient, time-saving and labor-saving; meanwhile, the scales on the surface of the sampling tube ensure the accuracy of gases corresponding to different soil depths. The problems that gas at different soil depths is difficult to collect and the soil structure is easy to damage are solved.

Description

Technical Field

[0001] The invention relates to the field of gas sample collection and monitoring devices, and in particular to a device and method for collecting greenhouse gases in different soil depths. Background Art

[0002] In situ measurement of greenhouse gas fluxes at different soil depths and collection of greenhouse gases are the key to studying greenhouse gas fluxes in terrestrial ecosystems, and are also important aspects of building global climate change models and predicting future greenhouse gas emissions.

[0003] Traditionally, the profile method or the hole method is used to collect greenhouse gases at different soil depths. However, the current methods still have the following problems: 1) The utilization rate of the holes drilled in the soil is not high, and each hole can only collect soil gas at one depth; 2) The sampling device is cumbersome to operate, easily destroys the soil structure, and requires a lot of manpower and material resources.

[0004] Therefore, in order to solve the above problems, the present invention provides a device for simply collecting and monitoring gases at different soil depths. Summary of the invention

[0005] In order to solve the problems that measuring or collecting greenhouse gases at different soil depths easily destroys the soil structure, traditional devices cannot collect gases at different depths at one time, and the utilization rate of the dug holes is low, the present invention provides a device for collecting greenhouse gases at different soil depths and a method for collecting gases using the device.

[0006] A device for collecting greenhouse gases at different soil depths, comprising a sampling chamber (1), a latex tube (2), a top device (3), a sampling tube (4), a sampling well (5), a top sealing rubber ring (6), a sampling rubber ring (7), a sealing rubber ring (8) and a sampling well top (9);

[0007] The sampling chamber (1) has a vent hole (10) on its surface, and is connected to the sampling well (5) on its side through a latex tube (2). The connections between the latex tube (2) and the sampling chamber (1) and the sampling well (5) are all sealed. The sampling tube (4) is located in the center of the sampling well (5). The top sealing rubber ring (6) and the sampling rubber ring (7) are both provided with holes in their centers. The sampling tube (4) passes through the holes in the centers of the top sealing rubber ring (6) and the sampling rubber ring (7) and is connected to the sealing rubber ring (8). The connections between the sampling tube (4) and the top sealing rubber ring (6), the sampling rubber ring (7) and the sealing rubber ring (8) are all sealed. A top device (3) is provided at the tube mouth of the sampling tube (4), and a sampling cavity (11) is provided between the top sealing rubber ring (6) and the sealing rubber ring (8).

[0008] The top sealing rubber ring (6), the sampling rubber ring (7) and the sealing rubber ring (8) are fixed in relative positions on the sampling tube (4) and can move up and down with the sampling tube to collect soil gas at different depths.

[0009] The sampling chamber (1) has a size of 20×5×5 (cm3), and has air holes (10) on its surface. The diameter of the air holes (10) is 6 to 8 mm, and a filter gauze is provided on the outside.

[0010] The latex tube (2) and the sampling well (5) are both made of freeze-resistant materials and can operate in low-temperature environments such as freezing periods or freeze-thaw periods.

[0011] The latex tube (2) has a diameter of 0.8 to 1 cm and a length of 5 to 8 cm.

[0012] The sampling well (5) has a diameter of 8 to 10 cm, a length of 50 to 60 cm, and a sealed upper end.

[0013] The sampling tube (4) has a diameter of 3 to 5 cm and a length of 55 to 65 cm. Its surface is graduated, starting from the sampling rubber ring (7). A section of the surface of the sampling tube (4) located below the sampling cavity (11) is provided with a hole.

[0014] The top sealing rubber ring (6), the sampling rubber ring (7) and the sealing rubber ring (8) have the same specifications, with a nominal outer diameter of 8 to 10 cm, a nominal inner diameter of 3 to 5 cm, and a cross-sectional diameter of 2 cm.

[0015] The top device (3) is a three-way valve, the lower side of which is connected to a sampling tube, the upper side of which is a sealing rubber pad for manual sampling, and the right side of which is connected to an automatic gas extraction device for continuous monitoring.

[0016] The distance between the top sealing rubber ring (6) and the sealing rubber ring (8) is 6 to 8 cm, and the sampling rubber ring (7) is located in the middle.

[0017] The sampling rubber ring (7) is surrounded by small holes (12), and the diameter of the small holes (12) is 0.8 to 1 cm.

[0018] Beneficial effects:

[0019] Compared with traditional methods, the present invention can effectively reduce soil disturbance, which is particularly important for research that requires high-frequency gas measurement. The materials used in the entire device are low-priced and suitable for long-term collection or continuous automatic monitoring of soil gas at different depths. It is convenient and efficient, saving time and effort; at the same time, the scale on the surface of the sampling tube ensures the accuracy of the gas corresponding to different soil depths.

[0020] In addition, the gas collection chamber and the sampling well are connected with latex tubes, which can maximize the protection that the collected gas is not affected by surface air. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the structure of soil gas collection devices at different depths;

[0022] Figure 2 It is a cross-sectional view of the sampling well portion of the collection device;

[0023] Figure 3 It is a schematic diagram of the top device structure;

[0024] Figure 4 Schematic diagram of the top device surface button (left) and the upper sealing gasket protective cover surface scale (right);

[0025] Figure 5 This is a diagram showing the use of the present invention to collect gas at a depth of 30 cm in the soil;

[0026] In the figure: 1. Sampling chamber, 2. Latex tube, 3. Top device, 4. Sampling tube, 5. Sampling well, 6. Top sealing rubber ring, 7. Sampling rubber ring, 8. Sealing rubber ring, 9. Top of sampling well, 10. Air vent, 11. Sampling cavity, 12. Small hole. DETAILED DESCRIPTION

[0027] The present invention is further described below in conjunction with specific implementations. The technical solution of the present invention is not limited to the following specific implementations, but also includes any combination of the specific implementations.

[0028] Embodiment 1: A device for collecting greenhouse gases at different soil depths

[0029] The device for collecting greenhouse gases in different soil depths of the present invention is composed of a sampling chamber 1, a latex tube 2, a top device 3, a sampling tube 4, a sampling well 5, a top sealing rubber ring 6, a sampling rubber ring 7, a sealing rubber ring 8 and a top 9 of the sampling well. The side of the sampling chamber 1 is connected to the sampling well 55 through the latex tube 2. The connection between the latex tube 2 and the sampling chamber 1 and the sampling well 5 is sealed. The sampling tube 4 is located in the center of the sampling well 5. There are holes in the top sealing rubber ring 7 and the center of the sampling rubber ring 7, and the sampling tube 4 passes through the holes in the center of the top sealing rubber ring 6 and the sampling rubber ring 7 and is connected to the sealing rubber ring 8. The connection between the sampling tube 4 and the top sealing rubber ring 6, the sampling rubber ring 7 and the sealing rubber ring 8 is sealed. The top device 3 is provided at the mouth of the sampling tube 4. There are holes at the bottom of the sampling tube 4 corresponding to the sampling cavity.

[0030] The diameter of the air holes 10 on the surface of the gas sampling chamber is 6 to 8 mm, and there is a filter gauze in the hole. The purpose of distributing numerous holes on the surface of the gas sampling chamber 1 is to ensure that soil gas can enter the sampling well 5 through the gas sampling chamber 1, and to ensure that the gas collected in the tube is a stable soil gas production amount after the inflow and outflow are balanced. The purpose of having a filter gauze in the hole is to ensure that soil and other soil materials cannot enter the sampling chamber to avoid clogging the sampling hole, and to provide a smooth passage for the inflow and outflow of soil gas.

[0031] Before collecting gas, sampling chambers are pre-buried at different soil depths to collect soil gas at different depths.

[0032] The latex tube is made of freeze-resistant material and can withstand extremely low temperatures, which can ensure that the collection device can work in low-temperature environments such as freezing period or freeze-thaw period.

[0033] The latex tube 2 has a diameter of 0.8 to 1 cm and a length of 5 to 8 cm. The purpose of the latex tube 2 is to connect the sampling chamber with the sampling well 5, so as to ensure that the soil gas in the sampling chamber enters the sampling well.

[0034] The material used for the sampling well 5 is a freeze-resistant material with a diameter of 8 to 10 cm and a length of 50 to 60 cm. The upper end of the sampling well 5 is sealed to prevent gas leakage in the sampling cavity or entry of external gas.

[0035] The sampling tube 4 has a scale on its surface, and the scale starts from the sampling rubber ring. The scale on the sampling tube 4 surface can be used to determine the sampling rubber ring to connect to latex tubes of different depths, thereby connecting to the gas sampling chamber of the same depth to achieve the purpose of collecting or monitoring soil gas at different depths.

[0036] There are small holes 12 around the sampling rubber ring 7. Every 30° rotation just makes the new small holes align with the latex tube, so that the gas in the gas sampling chamber can enter the sampling cavity 11, and it is also convenient to convert the holes on the sampling rubber ring 7 after they are worn.

[0037] The distance between the top sealing rubber ring 3 and the sealing rubber ring 8 is 6 to 8 cm, and the sampling rubber ring 7 is located in the middle. The space between the top sealing rubber ring 3 and the sealing rubber ring 8 is called the sampling cavity 11, and the upper and lower parts thereof are kept in a sealed state.

[0038] The top sealing rubber ring 3, the sampling rubber ring 7 and the sealing rubber ring 8 are fixed on the sampling tube 4 and can move up and down with the sampling tube 4 to facilitate the collection of soil gas at different depths.

[0039] Lubricant can be regularly added between the top sealing rubber ring 3, the sampling rubber ring 7, the sealing rubber ring 8 and the sampling well 5 to reduce the friction between the rubber ring and the inner wall of the sampling well 5, reduce the wear of the rubber ring, facilitate the pulling out of the sampling tube, and improve the sealing performance.

[0040] A hole is provided on the surface of the sampling tube 4 at the position corresponding to the sampling cavity 11 below the sampling tube 4. The diameter of the hole is 0.8 to 1 cm, so that the gas in the sampling cavity can enter the sampling tube.

[0041] The top 9 of the sampling well is a blind end with a pointed protrusion to facilitate the insertion of the sampling well into the soil.

[0042] The top device 3 is a three-way valve, the lower side is connected to the sampling tube 4, the upper side is a sealing pad for manual sampling, and the right side is connected to the automatic gas extraction device for continuous monitoring. The connection direction can be changed by rotating the button on the surface of the top device.

[0043] Embodiment 2: Manual sampling implementation method:

[0044] Step 1: pre-bury the gas sampling chamber 1 in the soil at the required sampling depth;

[0045] Step 2: Use a soil drill to take out a soil column whose depth and diameter match the depth and diameter of the sampling well at the corresponding position, and place the sampling well 5 into the corresponding soil column hole;

[0046] Step 3: Pull the sampling tube 4 to align the closed position above the sampling well 5 with the required scale on the sampling tube surface, and align the sampling rubber ring 7 with the latex tubes at different depths. Rotate the button on the surface of the top device 3 to connect the lower sampling tube with the upper sealing pad, and regularly use a syringe to pass through the sealing pad to extract soil gas samples and measure the greenhouse gas content in the soil. The pre-buried sampling chamber and sampling well do not need to be taken out and can be reused repeatedly.

[0047] Example 3: Automatic sampling implementation method:

[0048] The difference from the second embodiment is that the button on the surface of the top device 3 is rotated to connect the lower sampling tube 4 with the right automatic gas monitoring device to automatically measure the gas flux in the sampling tube 4.

Claims

1. A device for collecting greenhouse gases at different soil depths, characterized by: It is composed of a sampling chamber (1), a latex tube (2), a top device (3), a sampling tube (4), a sampling well (5), a top sealing rubber ring (6), a sampling rubber ring (7), a sealing rubber ring (8) and a top of the sampling well (9); The sampling chamber (1) has a vent hole (10) on its surface, and is connected to the sampling well (5) on its side through a latex tube (2). The connections between the latex tube (2) and the sampling chamber (1) and the sampling well (5) are all sealed. The sampling tube (4) is located in the center of the sampling well (5). The top sealing rubber ring (6) and the sampling rubber ring (7) are both provided with holes in their centers. The sampling tube (4) passes through the holes in the centers of the top sealing rubber ring (6) and the sampling rubber ring (7) and is connected to the sealing rubber ring (8). The connections between the sampling tube (4) and the top sealing rubber ring (6), the sampling rubber ring (7) and the sealing rubber ring (8) are all sealed. A top device (3) is provided at the tube mouth of the sampling tube (4), and a sampling cavity (11) is provided between the top sealing rubber ring (6) and the sealing rubber ring (8). The top sealing rubber ring (6), the sampling rubber ring (7) and the sealing rubber ring (8) are fixed in relative positions on the sampling tube (4) and can move up and down with the sampling tube.

2. The device for collecting greenhouse gases at different soil depths according to claim 1, characterized in that: The sampling chamber (1) has a size of 20×5×5 cm, and has air holes (10) on its surface. The diameter of the air holes (10) is 6 to 8 mm, and a filter gauze is provided outside.

3. The device for collecting greenhouse gases at different soil depths according to claim 2, characterized in that: The latex tube (2) and the sampling well (5) are both made of freeze-resistant materials and can operate in a low-temperature environment during the freezing period or the freeze-thaw period.

4. The device for collecting greenhouse gases at different soil depths according to claim 3, characterized in that: The latex tube (2) has a diameter of 0.8 to 1 cm and a length of 5 to 8 cm.

5. The device for collecting greenhouse gases at different soil depths according to claim 4, characterized in that: The sampling well (5) has a diameter of 8 to 10 cm, a length of 50 to 60 cm, and a sealed upper end.

6. The device for collecting greenhouse gases at different soil depths according to claim 5, characterized in that: The sampling tube (4) has a diameter of 3 to 5 cm and a length of 55 to 65 cm. Its surface is graduated, starting from the sampling rubber ring (7). A section of the surface of the sampling tube (4) located below the sampling cavity (11) is provided with a hole.

7. The device for collecting greenhouse gases at different soil depths according to claim 6, characterized in that: The top sealing rubber ring (6), the sampling rubber ring (7) and the sealing rubber ring (8) have the same specifications, with a nominal outer diameter of 8 to 10 cm, a nominal inner diameter of 3 to 5 cm, and a cross-sectional diameter of 2 cm.

8. The device for collecting greenhouse gases at different soil depths according to claim 7, characterized in that: The top device (3) is a three-way valve, the lower side of which is connected to a sampling tube, the upper side of which is a sealing rubber pad for manual sampling, and the right side of which is connected to an automatic gas extraction device for continuous monitoring.

9. The device for collecting greenhouse gases at different soil depths according to claim 8, characterized in that: The distance between the top sealing rubber ring (6) and the sealing rubber ring (8) is 6 to 8 cm, and the sampling rubber ring (7) is located in the middle.

10. The device for collecting greenhouse gases at different soil depths according to claim 9, characterized in that: The sampling rubber ring (7) is surrounded by small holes (12), and the diameter of the small holes (12) is 0.8 to 1 cm.

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