CN117190053A - Coalbed methane purification multi-stage gas buffer tank - Google Patents

Abstract

The invention provides a multi-stage gas buffer tank for coal bed methane purification, which relates to the technical field of coal bed methane adsorption equipment. It solves the problem to a certain extent that the existing multi-stage gas buffer tank for coal bed methane purification cannot quickly eliminate the pressure fluctuation of the fluid, resulting in the inability of the gas to The problem of stable and uniform output. The multi-stage gas buffer tank for coalbed methane purification provided by the invention includes a tank body, a first rectification device, a replacement device and a second rectification device; an air inlet and an air outlet are formed on the tank body, and the first rectification device corresponds to the air inlet. Set, the second rectification device is arranged corresponding to the air outlet, the replacement device is distributed with a plurality of air holes, the replacement device is arranged in the tank, and is located between the first rectification device and the second rectification device, and covers the radial direction of the tank The tank body is divided into a first air chamber and a second air chamber.

Description

Coalbed methane purification multi-stage gas buffer tank

Technical field

The invention relates to the technical field of coalbed methane adsorption equipment, and in particular to a multi-stage gas buffer tank for coalbed methane purification.

Background technique

At present, most buffer tanks used in petrochemical and other fields have a cavity structure inside, and there are no other devices inside the cavity. When the fluid pressure is too high, the pressure fluctuation of the fluid cannot be quickly eliminated, so that the fluid in the pipeline cannot always maintain a stable operation, and the flow state of the fluid cannot be changed when the buffer tank stores the fluid.

Therefore, there is an urgent need to provide a multi-stage gas buffer tank for coalbed methane purification to solve the problems existing in the existing technology to a certain extent.

Contents of the invention

The object of the present invention is to provide a multi-stage gas buffer tank for coalbed methane purification, which can transform the turbulent flow state of the air flow before entering the buffer tank into a laminar flow state of regular flow of air flow after passing through the buffer tank, with stable pressure and uniform flow rate. To a certain extent, it solves the problem that the current multi-stage gas buffer tank for coalbed methane purification cannot quickly eliminate the existing pressure fluctuations, resulting in the inability of the gas to be output stably and uniformly.

The invention provides a multi-stage gas buffer tank for coalbed methane purification, which includes a tank body, a first rectification device, a replacement device and a second rectification device; an air inlet and an air outlet are formed on the tank body, and the first The rectification device is arranged corresponding to the air inlet, the second rectification device is arranged corresponding to the air outlet, the replacement device is distributed with a plurality of air holes, the replacement device is arranged in the tank body, and is located in the Between the first rectifying device and the second rectifying device, and covering the tank body along the radial direction of the tank body, the tank body is divided into a first air chamber and a second air chamber.

Wherein, the first rectification device includes a first outer tube and a plurality of first bundle tubes; the first outer tube is connected to the tank body, and a plurality of the first bundle tubes are arranged on the first outer tube. inside the tube, and a plurality of the first bundle tubes are closely arranged inside the first outer tube.

Specifically, the first outer tube is formed with a beveled surface in the tank body and at one end away from the tank body, and the angle formed between the beveled surface and the horizontal plane is between 40° and 50°, One end of the plurality of first bundle tubes corresponding to the chamfered surface is arranged in cooperation with the chamfered surface.

Further, a first docking piece is provided at one end of the first outer tube away from the chamfered surface.

Wherein, the second rectification device includes a second outer tube and a plurality of second bundle tubes; the second outer tube is connected to the tank body, and a plurality of the second bundle tubes are arranged on the second outer tube. inside the tube, and a plurality of the second bundled tubes are closely arranged inside the second outer tube.

Specifically, a gas collection port is formed at one end of the second outer tube located in the tank body, and the gas collection port is funnel-shaped.

Further, the multi-stage gas buffer tank for coalbed methane purification provided by the present invention also includes an air cap, which is disposed between the ends of the plurality of second bundle tubes and the gas collection ports, and is located between the plurality of second tube bundles and the gas collection ports. At the center of the second bundle tube, an air guide surface is formed at the end of the hood, and the air guide surface is arc-shaped.

Further, a second connecting piece is provided at one end of the second outer tube located outside the tank body.

Wherein, the replacement device includes a baffle and a plurality of gas collecting pipe assemblies; a perforation is formed on the baffle, the perforations are arranged in one-to-one correspondence with the gas collecting pipe assemblies, and the gas collecting pipe assembly is arranged in the perforation. , and can slide relative to the baffle; the gas collecting pipe assembly includes a gas collecting pipe and a retaining ring. The two ends of the gas collecting pipe are respectively formed with abutting portions. The retaining ring is sleeved on the gas collecting pipe and is connected with the gas collecting pipe. The abutting portions of the gas collecting pipe located in the first air chamber are in contact with each other, and the air passage hole is formed at one end of the gas collecting pipe located in the second air chamber.

Specifically, the bottom of the tank is provided with a drain pipe and a support. The drain pipe is used to discharge the liquid in the tank, and the support is used to support the tank from the ground.

Compared with the existing technology, the multi-stage gas buffer tank for coalbed methane purification provided by the present invention has the following advantages:

The multi-stage gas buffer tank for coalbed methane purification provided by the invention includes a tank body, a first rectification device, a replacement device and a second rectification device; an air inlet and an air outlet are formed on the tank body, and the first rectification device corresponds to the air inlet. Set, the second rectification device is arranged corresponding to the air outlet, the replacement device is distributed with a plurality of air holes, the replacement device is arranged in the tank, and is located between the first rectification device and the second rectification device, and covers the radial direction of the tank The tank body is divided into a first air chamber and a second air chamber.

From this analysis, it can be seen that through the air inlet and air outlet formed by the tank, a first rectification device is provided at the air inlet position, and a second rectification device is provided at the air outlet position, so that the input can be only The gas in the tank is rectified once. Correspondingly, the gas that is about to be output from the tank can be finally rectified through the second rectification device, so that the pressure fluctuation of the gas can be eliminated to a certain extent through the first rectification device and the second rectification device. , so that the gas can be stably output from the tank.

Moreover, in this application, a replacement device is provided in the tank body, and the replacement device covers the tank body in the radial direction of the tank body. Therefore, the tank body can be divided into a first air chamber and a second air chamber. When the gas enters the tank body from the first rectification device, it can fill the first gas chamber, so that the gas can be initially buffered. Moreover, since the replacement device in the present application is formed with air holes, the buffer gas in the first air chamber can enter the second air chamber through the air holes, so that through the plurality of air holes distributed on the replacement device, the gas can be The first air chamber enters the second air chamber evenly and stably, further eliminating the pressure fluctuation after the gas enters the tank, thereby ensuring that the gas can be stably output from the tank.

Description of the drawings

In order to more clearly explain the specific embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings that need to be used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings in the following description The drawings illustrate some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without exerting any creative effort.

Figure 1 is a schematic diagram of the overall structure of a multi-stage gas buffer tank for coalbed methane purification provided by an embodiment of the present invention;

Figure 2 is a schematic structural diagram of the first rectification device in the multi-stage gas buffer tank for coalbed methane purification provided by an embodiment of the present invention;

Figure 3 is a schematic structural diagram of the second rectification device in the multi-stage gas buffer tank for coal bed methane purification provided by the embodiment of the present invention;

Figure 4 is a schematic structural diagram of a displacement device in a multi-stage gas buffer tank for coal bed methane purification provided by an embodiment of the present invention.

In the figure: 1-tank; 101-first air chamber; 102-second air chamber; 103-drain pipe; 104-support; 2-first rectification device; 201-first outer tube; 2011-oblique section ; 2012-First docking piece; 202-First bundle tube; 3-Second rectification device; 301-Second outer tube; 3011-Gas collection port; 3012-Second docking piece; 302-Second bundle tube; 303- Hood; 3031-wind guide surface; 4-replacement device; 401-baffle; 4011-perforation; 402-air collecting pipe; 4021-butting part; 4022-retaining ring; 4023-air hole.

Detailed ways

In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only These are part of the embodiments of this application, but not all of them. The components of the embodiments of the present application generally described and illustrated in the figures herein may be arranged and designed in a variety of different configurations. Accordingly, the following detailed description of the embodiments of the application provided in the appended drawings is not intended to limit the scope of the claimed application, but rather to represent selected embodiments of the application. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without any creative work shall fall within the scope of protection of this application.

In the description of the embodiments of this application, it should be noted that the terms "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. indicate The orientation or positional relationship is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the invention is usually placed when used. It is only for the convenience of describing the invention and simplifying the description, and is not an indication or implication. The devices or elements must have a specific orientation, be constructed and operate in a specific orientation, and therefore are not to be construed as limitations of the invention. In addition, the terms "first", "second", "third", etc. are only used to distinguish descriptions and shall not be understood as indicating or implying relative importance.

In addition, the terms "horizontal", "vertical", etc. do not mean that the component is required to be absolutely horizontal or suspended, but may be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical". It does not mean that the structure must be completely horizontal, but can be slightly tilted.

In the description of the embodiments of this application, it should also be noted that, unless otherwise clearly stated and limited, the terms "setting", "installation", "connection" and "connection" should be understood in a broad sense. For example, they can be fixed The connection may be a detachable connection or an integral connection; it may be a mechanical connection or an electrical connection; it may be a direct connection or an indirect connection through an intermediate medium; it may be an internal connection between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood on a case-by-case basis.

As used herein, the term "and/or" includes any one and any combination of two or more of the associated listed items.

For ease of description, spatially relative terms, such as “on,” “upper,” “below,” and “lower,” may be used herein to describe the relationship of one element to another as illustrated in the figures. component relationship. Such spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures.

The terms used herein are used only to describe various examples and are not intended to limit the disclosure. The singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. The terms "comprises," "comprises," and "having" enumerate the presence of stated features, quantities, operations, components, elements, and/or combinations thereof, but do not exclude the presence or addition of one or more other features, quantities, Operations, components, elements and/or combinations thereof.

Due to manufacturing techniques and/or tolerances, variations in the shapes shown in the drawings may occur. Accordingly, the examples described herein are not limited to the specific shapes shown in the drawings, but include changes in shape that occur during manufacturing.

Features of the examples described herein may be combined in various ways that will become apparent upon understanding the disclosure of this application. Furthermore, while the examples described herein have a wide variety of configurations, other configurations are possible, as will be apparent upon understanding the disclosure of this application. In addition, the technical solutions in various embodiments can be combined with each other, but it must be based on the realization by those of ordinary skill in the art. When the combination of technical solutions is contradictory or cannot be realized, it should be considered that such a combination of technical solutions does not exist. , nor is it within the scope of protection required by this application.

As shown in Figures 1 to 4, the present invention provides a multi-stage gas buffer tank for coal bed methane purification, including a tank body 1, a first rectification device 2, a replacement device 4 and a second rectification device 3; the tank body 1 is formed with For the air inlet and the air outlet, the first rectification device 2 is arranged corresponding to the air inlet, and the second rectification device 3 is arranged corresponding to the air outlet. A plurality of air holes 4023 are distributed on the replacement device 4, and the replacement device 4 is arranged in the tank 1. And it is located between the first rectification device 2 and the second rectification device 3, and covers the tank 1 along the radial direction of the tank 1, so as to divide the tank 1 into a first air chamber 101 and a second air chamber 102.

Compared with the existing technology, the multi-stage gas buffer tank for coalbed methane purification provided by the present invention has the following advantages:

The coalbed methane purification multi-stage gas buffer tank provided by the present invention has an air inlet and an air outlet formed by the tank 1, and a first rectification device 2 is provided at the air inlet position, and a second rectification device 3 is provided at the air outlet position. , so that the gas input into only the tank 1 can be rectified once through the first rectification device 2. Correspondingly, the gas that is about to be output from the tank 1 can be finally rectified through the second rectification device 3, so that through the first rectification The device 2 and the second rectifying device 3 can eliminate the pressure fluctuation of the gas to a certain extent, so that the gas can be stably output from the tank 1.

Moreover, in this application, a replacement device 4 is also provided in the tank 1, and the replacement device 4 covers the tank 1 in the radial direction of the tank 1. Therefore, the tank 1 can be divided into the first air chamber 101 and the first air chamber 101. The second air chamber 102. When the gas enters the tank 1 from the first rectifying device 2, it can fill the first air chamber 101. Moreover, since the replacement device 4 in this application is formed with a gas hole 4023, the gas in the first air chamber 101 It can enter the second air chamber 102 through the air holes 4023, so that through the multiple air holes 4023 distributed on the replacement device 4, the gas can stably enter the second air chamber 102 from the first air chamber 101, further eliminating the gas. The pressure fluctuation after entering the tank 1 ensures that the gas can be stably output from the tank 1.

Optionally, as shown in Figure 1 in combination with Figure 2, the first rectification device 2 in this application includes a first outer tube 201 and a plurality of first tube bundles 202; the first outer tube 201 is connected to the tank 1, and the first outer tube 201 is connected to the tank 1. A first bundle tube 202 is disposed in the first outer tube 201, and a plurality of first bundle tubes 202 are closely arranged in the first outer tube 201.

By closely arranging a plurality of first tube bundles 202 in the first outer tube 201, the first outer tube 201 can be divided into multiple air channels, so that when the gas enters the tank 1 from the first rectifying device 2, it can be distributed By flowing into the plurality of first bundle tubes 202, the gas originally in a turbulent flow state can be preliminarily rectified into a state close to laminar flow, and the gas flow rate can be reduced and the gas flow pressure can be stabilized.

Preferably, as shown in Figure 2, the first outer tube 201 in this application is inside the tank 1, and has a beveled surface 2011 formed at one end away from the tank 1, and the angle formed between the beveled surface 2011 and the horizontal plane is Between 40° and 50°, one end of the plurality of first bundle tubes 202 corresponding to the beveled surface 2011 is arranged to cooperate with the beveled surface 2011.

In this application, by forming a beveled surface 2011 at one end of the first outer tube 201 away from the tank 1, the flow area of the first outer tube 201 can be increased, thereby increasing the air intake volume.

It can be understood that the first outer tube 201 in this application has a cylindrical structure. The beveled surface 2011 formed at one end can make the end surface of the first outer tube 201 elliptical, thereby increasing the flow area. It is further preferred that the angle between the oblique plane 2011 in this application and the horizontal plane is 45°, so as to maximize the area of the elliptical air outlet surface formed, thereby maximizing the air intake volume and ensuring the air intake and rectification effects.

What needs to be supplemented here is that when processing the first rectifying device 2 provided in this application, the end of the first outer tube 201 is first cut obliquely to form an oblique section 2011 with an angle of 45° to the horizontal plane. After that, the plurality of first bundle tubes 202 are inserted into the first outer tube 201. The above-mentioned one end of the first bundle tube 202 corresponding to the chamfered surface 2011 is arranged to match the chamfered surface 2011. This means that the plurality of first bundled tubes 202 are inserted into the first outer tube 201. The bundle tubes 202 have different lengths, and by arranging the first bundle tubes 202 of different lengths in the first outer tube 201 according to the angle of the oblique section 2011, the end surface formed by the plurality of first bundle tubes 202 can be aligned with the oblique section. It remains consistent in 2011, thus ensuring the maximum flow area and increasing the air intake volume.

Optionally, as shown in Figure 2, the end of the first outer tube 201 in this application away from the bevel 2011 is provided with a first connecting piece 2012, and the first connecting piece 2012 is a flange, which can be connected with the air supply pipeline. docking to realize the supply of gas into the tank 1 .

Optionally, as shown in Figure 3, the second rectification device 3 in this application includes a second outer tube 301 and a plurality of second tube bundles 302; the second outer tube 301 is connected to the tank 1, and a plurality of second tube bundles 302 are connected to the tank body 1. The bundle tube 302 is disposed in the second outer tube 301 , and a plurality of second bundle tubes 302 are closely arranged in the second outer tube 301 .

By closely arranging a plurality of second tube bundles 302 in the second outer tube 301, the second outer tube 301 can be divided into multiple air channels, so that when the gas enters the second outer tube 301 from the second air chamber 102, The flow can be distributed into multiple first bundle tubes 202, and the gas entering the second air chamber 102 can be further rectified and output, so that the output air flow is in a laminar flow state and the stability of the output air flow pressure is improved.

Preferably, as shown in Figure 3, the second outer tube 301 in this application is formed with a gas collection port 3011 at one end located in the tank 1, and the gas collection port 3011 is funnel-shaped. It can be understood that a funnel-shaped gas collection port 3011 can have a better gas gathering effect, allowing the gas to enter the second outer tube 301 and flow to the second bundle tube 302.

Optionally, as shown in Figure 3, the coalbed methane purification multi-stage gas buffer tank provided by the present invention also includes an air cap 303. The air cap 303 is disposed between the ends of the plurality of second bundle tubes 302 and the gas collection port 3011, and Located at the center of the plurality of second bundle tubes 302, an air guide surface 3031 is formed at an end of the hood 303, and the air guide surface 3031 is arc-shaped.

Since the gas entering the second air chamber 102 through the replacement device 4 is closer to a laminar flow state, and the flow rate in the center area of the laminar flow state is fast and the flow rate around it is slow, therefore, the present application uses Installing the hood 303 at the center can slow down and guide the airflow with fast flow speed in the center. When the air contacts the air guide surface 3031 of the hood 303, since the air guide surface 3031 is arc-shaped, the airflow can be directed to the surroundings, thus It can not only slow down the gas flow rate in the central area, but also increase the surrounding gas flow rate to achieve a balanced state of air flow, so that the gas flow rate entering the plurality of second bundle tubes 302 is basically consistent, and thus the output through the second bundle tube 302 can be maintained The gas reaches a laminar flow state to ensure stable gas pressure.

Optionally, as shown in Figure 3, the second outer pipe 301 in this application is provided with a second connecting piece 3012 at one end outside the tank 1, and the second connecting piece 3012 also uses a flange, so that it can be connected with the outlet. The gas pipeline is connected to realize the output of gas.

Optionally, as shown in Figure 4, the replacement device 4 in this application includes a baffle 401 and a plurality of gas collecting pipe 402 assemblies; the baffle 401 is formed with perforations 4011, and the perforations 4011 are arranged in one-to-one correspondence with the gas collecting pipe 402 components. The gas collecting pipe 402 assembly is arranged in the perforation 4011 and can slide relative to the baffle 401; the gas collecting pipe 402 assembly includes the gas collecting pipe 402 and a retaining ring 4022. The two ends of the gas collecting pipe 402 are respectively formed with abutment portions 4021, and the retaining ring 4022 is sleeved On the gas collecting pipe 402, and in contact with the contact portion 4021 of the gas collecting pipe 402 located in the first air chamber 101, an air passage 4023 is formed at one end of the gas collecting pipe 402 located in the second air chamber 102.

It can be understood that the hole diameter of the perforation 4011 in this application is slightly larger than the diameter of the gas collecting pipe 402, so that the gas collecting pipe 402 can slide relative to the baffle 401. The gas collecting pipe 402 can slide relative to the baffle 401 because when the gas enters the first air chamber 101 from the first rectifying device 2, the pressure of the first gas chamber 101 can be continuously increased, thereby pushing the gas collecting pipe 402 gradually toward the The direction entering the second air chamber 102 slides relative to the baffle 401 .

Since the contact portions 4021 are formed at both ends of the gas collecting pipe 402 in this application, and the air hole 4023 is formed at one end of the gas collecting pipe 402 located in the second gas chamber 102, when the gas is continuously input into the first gas chamber 101 When inside, the air pressure in the first air chamber 101 can push the air collecting pipe 402 to slide in the direction of the second air chamber 102 relative to the baffle 401. When the abutment portion 4021 located in the first air chamber 101 abuts against the baffle 401 , the gas collecting pipe 402 no longer slides. Since the baffle ring 4022 abuts the abutment portion 4021 of the gas collecting pipe 402 in the first air chamber 101, the baffle ring 4022 can seal the abutment portion 4021 and the baffle 401 to a certain extent, so that The gas can only be discharged into the second air chamber 102 through the gas collecting pipe 402 and the air hole 4023.

When there is no more air intake in the first air chamber 101 or the amount of air intake decreases, the air collecting pipe 402 moves downward relative to the baffle 401 under the influence of gravity, so that the abutment portion 4021 located in the second air chamber 102 can contact the baffle plate 402 . 401 are in contact with each other to limit the position of the gas collecting pipe 402. Moreover, as shown in Figure 4, since the air hole 4023 in this application is located on the side wall of the gas collecting pipe 402, when the contact portion in the second air chamber 102 When 4021 is in contact with the baffle 401, the baffle 401 can block the air hole 4023, so that the gas collecting pipe 402 no longer conducts gas, thereby causing the pressure in the first air chamber 101 to continue to rise until the gas collecting pipe can be pushed 402 moves upward to allow the gas to enter the second air chamber 102 again to realize automatic pressure regulation.

Preferably, as shown in Figure 1, the bottom of the tank 1 in this application is provided with a drain pipe 103 and a support 104. The drain pipe 103 is used to discharge the liquid in the tank 1, and the support 104 is used to drain the tank 1 Off the ground.

The drain pipe 103 is connected to the bottom of the tank 1 and can discharge the liquid in the tank 1 . The support 104 provided at the bottom of the tank 1 can support the tank 1 and make the tank 1 Set away from the ground.

The above descriptions are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included in the present invention. within the scope of protection.

Claims (10)

1. The multi-stage gas buffer tank for purifying the coalbed methane is characterized by comprising a tank body, a first rectifying device, a replacing device and a second rectifying device;

the tank body is provided with an air inlet and an air outlet, the first rectifying device is arranged corresponding to the air inlet, the second rectifying device is arranged corresponding to the air outlet, a plurality of air passing holes are distributed on the replacing device, the replacing device is arranged in the tank body and is located between the first rectifying device and the second rectifying device, and the tank body is radially covered along the tank body so as to divide the tank body into a first air chamber and a second air chamber.

2. The coalbed methane purification multistage gas buffer tank of claim 1, wherein the first rectifying device comprises a first outer tube and a plurality of first bundle tubes;

the first outer tube is connected with the tank body, a plurality of first beam tubes are arranged in the first outer tube, and a plurality of first beam tubes are closely arranged in the first outer tube.

3. The multi-stage gas buffer tank for purifying coal bed gas according to claim 2, wherein the first outer tube is arranged in the tank body, a chamfer is formed at one end far away from the tank body, an included angle formed between the chamfer and a horizontal plane is 40 ° -50 °, and one ends of the first bundle of tubes corresponding to the chamfer are matched with the chamfer.

4. A coalbed methane purification multistage gas buffer tank as claimed in claim 3, wherein the end of the first outer tube remote from the chamfer is provided with a first abutment.

5. The coalbed methane purification multistage gas buffer tank of claim 1, wherein the second rectifying device comprises a second outer tube and a plurality of second beam tubes;

the second outer tube is connected with the tank body, a plurality of second beam tubes are arranged in the second outer tube, and a plurality of second beam tubes are closely arranged in the second outer tube.

6. The multi-stage gas surge tank for purifying coal bed gas of claim 5, wherein a gas collecting port is formed at one end of the second outer tube located in the tank body, and the gas collecting port is funnel-shaped.

7. The multi-stage gas buffer tank for purifying coal bed gas according to claim 6, further comprising a hood, wherein the hood is disposed between the ends of the plurality of second bundles and the gas collecting port and is located at the center of the plurality of second bundles, and the ends of the hood are formed with air guiding surfaces, and the air guiding surfaces are arc-shaped.

8. The multi-stage gas buffer tank for purifying coal bed gas as recited in claim 5, wherein a second butt joint member is arranged at one end of the second outer pipe located outside the tank body.

9. The coalbed methane purification multistage gas buffer tank of claim 1, wherein the displacement device comprises a baffle and a plurality of header assemblies;

the baffle is provided with perforations, the perforations are arranged in one-to-one correspondence with the gas collecting tube assemblies, and the gas collecting tube assemblies are arranged in the perforations and can slide relative to the baffle;

the gas collecting tube assembly comprises a gas collecting tube and a retaining ring, wherein the two ends of the gas collecting tube are respectively provided with an abutting part, the retaining ring is sleeved on the gas collecting tube and is abutted with the abutting part of the gas collecting tube in the first gas chamber, and the gas passing hole is formed in one end of the gas collecting tube in the second gas chamber.

10. The multi-stage gas buffer tank for purifying coal bed gas according to claim 1, wherein a drain pipe and a support are arranged at the bottom of the tank body, the drain pipe is used for draining liquid in the tank body, and the support is used for supporting the tank body off the ground.