Device for pressure reduction and desorption of coalbed methane

Abstract

The present invention relates to a device for pressure reduction and desorption of coalbed methane. The device for pressure reduction and desorption of coalbed methane comprises a gas storage tank and a pressure regulating mechanism. The gas storage tank comprises an outer tank and an inner tank. A gap is formed between each outer wall of the inner tank and each inner wall of the outer tank. An air inlet pipe and an air outlet pipe are arranged at the top of the outer tank. The upper end of the air inlet pipe and the upper end of the air outlet pipe extend out of the outer tank, the lower end of the air inlet pipe extends into the bottom of the inner tank, and the lower end of the air outlet pipe is located in a gap between the top of the outer tank and an opening in the upper end of the inner tank. The inner tank is filled with an adsorption medium. The pressure regulating mechanism comprises piston plates. Each piston plate is in the shape of a ring plate and is located between the peripheral outer wall of the inner tank and the corresponding peripheral inner wall of the outer tank. The present invention provides a device for pressure reduction and desorption of coalbed methane, aiming to solve or at least mitigate the safety risks posed to storage and transportation tanks during transport and storage, which arise when the saturated adsorption capacity of adsorption media inside the storage and transportation tanks decreases due to temperature increases.

Description

A pressure reduction and desorption device for coalbed methane Technical Field

[0001] The present invention belongs to the technical field of coalbed methane application, and relates to a coalbed methane pressure reduction and desorption device, in particular to a coalbed methane pressure reduction and desorption device during adsorption, transportation, storage and use. Background Art

[0002] Coalbed methane (CBM) is a type of natural gas with methane as its main component, found in coal seams. It is a type of natural gas with methane accounting for 80%-90%. It is produced during coalification projects and coexists with coal. It is also known as gas. It is a potential clean energy source with extremely rich reserves. According to the International Energy Agency, the world's onshore coalfields with a depth of more than 2,000 meters have approximately 260 trillion cubic meters of CBM resources. 3 , which is more than twice the proven reserves of conventional natural gas. my country has abundant coalbed methane resources, with more than 500 billion m 3 There are 14 coalbed methane basins in China, with a total coalbed methane geological resource of approximately 36 trillion m3 at a depth of less than 2,000 m. 3 The geological resources of coalbed methane at depths of less than 1000m, 1000-1500m and 1500-2000m account for 38.8%, 28.8% and 32.4% of the total geological resources of coalbed methane in China respectively. However, due to a series of technical difficulties, the utilization rate of coalbed methane in my country is very low at this stage. These technical difficulties mainly include mining technology and storage and transportation technology. Among them, storage and transportation technology mainly includes compression transportation and adsorption transportation. The traditional gas storage and transportation method is compression transportation. The pressure of its storage and transportation tank is as high as 25MPa, which is very dangerous when filling and transporting flammable gases. Correspondingly, the method of storing and transporting coalbed methane after adsorption by adsorption media, such as activated carbon, does not require deep compression of the gas, saves energy, and has high safety performance. It is a very promising transportation method. Technical issues

[0003] However, after the adsorption and transportation is completed, the gas needs to be desorbed before it can be used. The desorption process has the disadvantages of complex equipment, large investment of equipment, poor desorption effect and high operating costs.

[0004] To ensure that the tanks can hold a large amount of coalbed methane, the adsorption medium inside them is mostly in a saturated adsorption state during storage and transportation. The saturated adsorption capacity of the adsorption medium decreases with increasing temperature, so the adsorption medium is mostly at a lower temperature when adsorbing coalbed methane. However, maintaining a lower temperature is not recommended during transportation. However, the internal space of the tank is fixed, and as the saturated adsorption capacity of the adsorption medium decreases, coalbed methane will be released, increasing the pressure inside the tank and posing a safety hazard during transportation and storage. Technical Solutions

[0005] The purpose of the present invention is to overcome the deficiencies in the prior art, solve or at least alleviate the problem that when the saturated adsorption capacity of the adsorption medium in the storage tank decreases due to temperature increase, it poses a safety hazard to the storage tank during transportation and storage, and provide a pressure reduction and desorption device for coalbed methane.

[0006] The present invention is achieved through the following technical solutions:

[0007] A pressure-reducing and desorbing coalbed methane device, comprising a gas storage tank and a pressure regulating mechanism, wherein the gas storage tank comprises an outer tank and an inner tank, wherein the outer tank is in the shape of a hollow shell, and the inner tank is in the shape of a shell with an upper end open and fixedly arranged in the outer tank, wherein gaps are left between each outer wall of the inner tank and each inner wall of the outer tank, and an air inlet pipe and an air outlet pipe are provided on the top of the outer tank, wherein the upper ends of the air inlet pipe and the air outlet pipe extend out of the outer tank, and the lower end of the air inlet pipe extends into the bottom of the inner tank, and the lower end of the air outlet pipe is located in the gap between the top of the outer tank and the upper opening of the inner tank, and the inner tank is filled with an adsorption medium;

[0008] The pressure regulating mechanism includes a piston plate, which is an annular flat plate and is located between the outer wall of the inner tank and the inner wall of the outer tank. The inner and outer sides of the piston plate are respectively sealed and longitudinally slidably connected to the outer wall of the inner tank and the inner wall of the outer tank.

[0009] In order to further realize the present invention, the following technical solutions may be preferably used:

[0010] Preferably, a positioning group is provided between the outer wall of the inner tank and the inner wall of the outer tank. There are two positioning groups, which are respectively located at the upper and lower parts of the inner tank. The positioning group includes several positioning plates arranged in a circular array. The inner and outer sides of the positioning plates are fixedly connected to the inner tank and the outer tank respectively, and the piston plate is located between the two positioning groups.

[0011] Preferably, the pressure reduction and desorption coalbed methane device also includes a temperature control component for adjusting the temperature of the adsorption medium. The bottom surface of the inner tank is provided with a concave temperature control chamber. The temperature control chamber is vertically arranged and the lower end is connected to the gap formed between the bottom surface of the outer tank and the bottom surface of the inner tank. The temperature control component is arranged in the temperature control chamber.

[0012] Preferably, the temperature regulating assembly comprises a temperature regulating shell, the upper portion of the temperature regulating shell is a shell having an open lower end corresponding to the shape of the temperature regulating chamber, and the outer wall of the temperature regulating shell is thermally bonded to the inner wall of the temperature regulating chamber;

[0013] An upper partition and a lower partition are respectively arranged transversely at the upper and lower parts of the temperature regulating shell, and the upper and lower partitions divide the internal space of the temperature regulating shell into a liquid storage section, a medicine storage section and a communication section from top to bottom. A liquid guide tube is longitudinally arranged in the medicine storage section, and the upper and lower ends of the liquid guide tube are respectively connected to the liquid storage section and the communication section, and the outer wall of the liquid guide tube is uniformly distributed with micropores;

[0014] Water is stored in the liquid storage section, quicklime is stored in the medicine storage section, and the communication section is connected to the gap formed between the bottom surface of the outer tank and the bottom surface of the inner tank.

[0015] Preferably, the bottom surface of the outer tank is provided with an inlet and outlet, the inlet and outlet are located directly below the temperature regulating chamber and have the same shape as the cross-section of the inner wall of the temperature regulating chamber, and the inlet and outlet are sealed with an inner sealing plate, the inner sealing plate is located in the outer tank and one side of the inner sealing plate is rotatably connected to the bottom surface of the outer tank;

[0016] A torsion spring and a limit block are provided between the inner sealing plate and the outer tank, and the torsion spring and the limit block drive the inner sealing plate to be located at the inlet and outlet of the bottom surface of the outer tank.

[0017] Preferably, the lower surface of the inner sealing plate is provided with an inwardly concave spiral slideway, the center of the circle where the slideway is located is located at the transition between the inner sealing plate and the bottom surface of the outer tank, the lower end of the slideway is connected to the lower surface of the inner sealing plate, and the upper end is connected to the side wall of the inner sealing plate, and a stopper is sealed at the connection between the upper end of the slideway and the side wall of the inner sealing plate, and the upper part of the stopper is hinged to the inner sealing plate by a torsion spring, and the torsion spring drives the stopper to seal and fit the side wall of the inner sealing plate;

[0018] The top surface of the temperature regulating shell is an outwardly convex arc surface, and a guide rod is vertically fixed outside the top surface of the temperature regulating shell. The upper end of the guide rod is in an outwardly convex hemispherical shape and is arranged corresponding to the slide of the inner sealing plate; when the temperature regulating shell enters the inlet and outlet of the outer tank, the upper end of the guide rod slides and is embedded in the slide of the inner sealing plate.

[0019] Preferably, a positioning sleeve is fixedly provided on the outside of the inlet and outlet of the outer tank, a positioning strip is longitudinally provided on the inner wall of the positioning sleeve, an outer sealing plate is detachably provided on the lower end of the positioning sleeve, a bottom plate is detachably provided at the lower part of the temperature control shell, and positioning grooves corresponding to the positioning strips are provided on the outside of the temperature control shell and the outside of the bottom plate.

[0020] Preferably, the pressure reduction and desorption coalbed methane device further includes a base, and a plurality of gas storage tanks are arranged on the upper part of the base, and both sides of the middle part of the gas storage tanks are rotatably connected to the base.

[0021] Preferably, a partition is laterally arranged on the upper part of the inner tank, and the adsorption medium is filled between the partition and the bottom of the inner tank. The adsorption medium includes but is not limited to solid materials such as activated carbon, molecular sieve, bentonite, etc. The partition prevents the adsorption medium from falling from the inner tank and does not hinder the passage of coalbed methane.

[0022] Preferably, the base is provided with a hydraulic cylinder, and the number of the hydraulic cylinders is equal to that of the gas tanks and they are arranged in a one-to-one correspondence. The hydraulic cylinder is located below the gas tank, the piston rod of the hydraulic cylinder extends vertically upward and a transducer is fixedly provided at the end of the piston rod, the upper surface of the transducer contacts the lower surface of the gas tank, and the transducer is connected to an ultrasonic generator. Beneficial effects

[0023] Through the above technical solution, the beneficial effects of the present invention are:

[0024] The present invention is provided with a temperature regulating component. When the gas tank is transported to the destination and prepared for desorption, the temperature regulating component is installed in the gas tank. In the early stage, the pressure in the gas tank is relatively high, the desorption rate of the coalbed methane is relatively high, and the coalbed methane output from the gas outlet pipe can meet normal use. At this time, the pressure in the gas tank is much higher than the atmospheric pressure, and the water in the liquid storage section of the temperature regulating shell will not flow out. As the coalbed methane is used, the pressure in the gas tank gradually decreases, the desorption rate of the coalbed methane decreases, and the coalbed methane output from the gas outlet pipe cannot meet normal use. When the pressure in the gas tank is close to or lower than the atmospheric pressure, the water in the liquid storage section of the temperature regulating shell flows into the drug storage section through the liquid guide pipe. The water generates heat when it encounters the quicklime stored in the drug storage section, which increases the temperature of the adsorption medium, thereby reducing the saturated adsorption capacity of the adsorption medium and indirectly increasing the desorption rate of the coalbed methane, so that the coalbed methane output from the gas outlet pipe can meet normal use.

[0025] In addition, the inlet and outlet of the bottom surface of the outer tank of the present invention are provided with an inner sealing plate. The inner sealing plate is located inside the outer tank. The pressure within the gas storage tank presses the inner sealing plate against the outer tank, ensuring the airtightness of the gas storage tank. Simultaneously, a slide is provided on the lower surface of the inner sealing plate, and a guide rod is provided on the top surface of the temperature-regulating shell. When the temperature-regulating shell is placed into the gas storage tank, the upper end of the guide rod abuts the bottom surface of the slide. As the temperature-regulating shell moves into the gas storage tank, the guide rod moves vertically, causing the inner sealing plate to move to one side and open. This inner sealing process does not require additional power, not only ensuring airtightness, but also avoiding accidental ignition and explosion caused by the use of electrical energy, thus ensuring safety.

[0026] The gas storage tank of the present invention is rotatably arranged above the base. When placing the temperature regulating shell, the gas storage tank is turned 180 degrees so that the bottom surface of the outer tank faces upward, and the temperature regulating shell is placed in a state where the liquid storage section is located at the lower end and then installed into the gas storage tank, thereby preventing water in the liquid storage section from entering the medicine storage section and facilitating operation. After the temperature regulating shell is installed, the gas storage tank is turned 180 degrees again, and the pressure in the liquid storage section prevents water from flowing out of the liquid storage section. At this time, the piston rod of the hydraulic cylinder rises and reaches the gas storage tank, so that the gas storage tank is in a stable state.

[0027] The present invention also includes a transducer and ultrasonic generator. Under the action of sound waves, the diffusion coefficient of coalbed methane increases, and the higher the sound intensity, the greater the value. The sound waves increase the diffusion rate of coalbed methane. Under the action of sound waves, the internal diffusion resistance of the adsorption medium is reduced, the diffusion capacity is enhanced, and the mass transfer rate is accelerated. Simultaneously, the sound waves gradually increase the temperature of the adsorption medium, reducing the adsorption medium's saturated adsorption capacity. Used in conjunction with a temperature control component, this ensures that the coalbed methane output from the outlet pipe is in a state sufficient for normal use, and the ultrasonic waves will not cause coalbed methane explosions, making it safe and reliable to use. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] FIG1 is a schematic structural diagram of the present invention;

[0029] FIG2 is a front view of the present invention;

[0030] FIG3 is a schematic structural diagram of a gas storage tank according to the present invention;

[0031] FIG4 is a cross-sectional view of the structure of the gas storage tank of the present invention in use;

[0032] FIG5 is an enlarged view of point A in FIG4 of the present invention;

[0033] FIG6 is a cross-sectional view of the structure of the gas storage tank of the present invention in a transport state;

[0034] FIG7 is a schematic structural diagram of a temperature control assembly according to the present invention;

[0035] FIG8 is a cross-sectional view of the structure of the temperature control assembly of the present invention;

[0036] FIG9 is a schematic structural diagram of the inner sealing plate of the present invention;

[0037] FIG10 is a bottom view of the inner sealing plate of the present invention;

[0038] FIG11 is a schematic structural diagram of a base according to the present invention;

[0039] Including: 1-gas storage tank; 2-air inlet pipe; 3-air outlet pipe; 4-adsorption medium; 5-piston plate; 6-positioning plate; 7-temperature control chamber; 8-temperature control shell; 9-upper partition; 10-lower partition; 11-liquid guide tube; 12-water; 13-quicklime; 14-inner sealing plate; 15-stopper; 16-guide rod; 17-slideway; 18-positioning sleeve; 19-outer sealing plate; 20-bottom plate; 21-base; 22-screen; 23-hydraulic cylinder; 24-transducer; 25-ultrasonic generator; 101-outer tank; 102-inner tank. Modes for Carrying Out the Invention

[0040] In the description of the present invention, it should also be noted that, unless otherwise expressly specified or limited, the terms "disposed," "installed," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to mechanical connections or electrical connections; they may refer to direct connections or indirect connections through an intermediate medium; and they may refer to internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0041] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention. Example 1:

[0042] As shown in Figure 1-11, a pressure reduction and desorption coalbed methane device, the pressure reduction and desorption coalbed methane device includes a gas storage tank 1 and a pressure regulating mechanism, the gas storage tank 1 includes an outer tank 101 and an inner tank 102, the outer tank 101 is hollow cylindrical, the inner tank 102 is cylindrical with an upper end opening and is coaxially fixedly arranged in the outer tank 101, and gaps are left between each outer wall of the inner tank 102 and each inner wall of the outer tank 101, an air inlet pipe 2 and an air outlet pipe 3 are provided at the top of the outer tank 101, the upper ends of the air inlet pipe 2 and the air outlet pipe 3 both extend out of the outer tank 101, the lower end of the air inlet pipe 2 extends into the bottom of the inner tank 102, and the lower end of the air outlet pipe 3 is located in the gap between the top of the outer tank 101 and the upper opening of the inner tank 102, the inner tank 102 is filled with an adsorption medium 4; the air inlet pipe 2 and the air outlet pipe 3 are both provided with valves and one-way valves, and the outer tank 101 is provided with a pressure gauge;

[0043] The pressure regulating mechanism includes a piston plate 5, which is in the shape of a circular flat plate and is located between the outer wall of the inner tank 102 and the inner wall of the outer tank 101. The inner and outer sides of the piston plate 5 are respectively sealed and longitudinally slidably connected to the outer wall of the inner tank 102 and the inner wall of the outer tank 101.

[0044] In order to limit the upper and lower extreme positions of the piston plate 5 and improve the reliability of the connection between the inner tank 102 and the outer tank 101, a positioning group is arranged between the outer wall of the inner tank 102 and the inner wall of the outer tank 101. There are two positioning groups, and the two positioning groups are respectively located at the upper and lower parts of the inner tank 102. The positioning group includes a number of positioning plates 6 arranged in a circular array. The inner and outer sides of the positioning plate 6 are fixedly connected to the inner tank 102 and the outer tank 101 respectively, and the piston plate 5 is located between the two positioning groups.

[0045] The piston plate 5 divides the interior of the gas tank 1 into two sealed spaces: one is the storage space, where the adsorption medium 4 is placed to absorb and store coalbed methane, and the other is the regulating space. After the gas tank 1 is filled with coalbed methane, the pressure in the storage space and the regulating space are equal. As the adsorption medium 4 heats up and releases coalbed methane, the pressure in the storage space increases. This pressure becomes greater than the pressure in the regulating space, driving the piston plate 5 downward, increasing the storage space and decreasing the pressure. When the pressure in the storage space and the regulating space equalize, the piston plate 5 stops moving. The pressure regulating mechanism is located within the gas tank 1 and does not require an external power source, making the gas tank 1 simple and easy to use.

[0046] At the same time, the adsorption medium 4 is filled in the inner tank 102 , and gaps are left between the outer walls of the inner tank 102 and the inner walls of the outer tank 101 , which has a heat insulation effect and can effectively reduce the temperature change of the adsorption medium 4 .

[0047] The pressure reduction and desorption coalbed methane device also includes a temperature control component for adjusting the temperature of the adsorption medium 4. A concave temperature control chamber 7 is provided on the bottom surface of the inner tank 102. The temperature control chamber 7 is vertically arranged and the lower end is connected to the gap formed between the bottom surface of the outer tank 101 and the bottom surface of the inner tank 102. The temperature control component is arranged in the temperature control chamber 7.

[0048] In order to optimize the product structure, the temperature control component includes a temperature control shell 8, the upper part of the temperature control shell 8 is a shell with an open lower end corresponding to the shape of the temperature control chamber 7, and the outer wall of the temperature control shell 8 is thermally bonded to the inner wall of the temperature control chamber 7;

[0049] An upper partition 9 and a lower partition 10 are respectively arranged transversely at the upper and lower parts of the temperature regulating shell 8. The upper partition 9 and the lower partition 10 divide the internal space of the temperature regulating shell 8 into a liquid storage section, a medicine storage section and a communication section from top to bottom. A liquid guide tube 11 is longitudinally arranged in the medicine storage section. The upper and lower ends of the liquid guide tube 11 are respectively connected to the liquid storage section and the communication section. The outer wall of the liquid guide tube 11 is uniformly distributed with micropores.

[0050] The liquid storage section stores water 12 , the drug storage section stores quicklime 13 , and the communication section is connected to the gap formed between the bottom surfaces of the outer tank 101 and the inner tank 102 .

[0051] In order to facilitate the placement of the temperature regulating shell 8, an inlet and outlet are provided on the bottom surface of the outer tank 101. The inlet and outlet are located directly below the temperature regulating chamber 7 and have the same shape as the cross-section of the inner wall of the temperature regulating chamber 7. An inner sealing plate 14 is provided at the inlet and outlet to seal the inner sealing plate 14. The inner sealing plate 14 is located inside the outer tank 101 and one side thereof is rotatably connected to the bottom surface of the outer tank 101.

[0052] A torsion spring and a limit block are provided between the inner sealing plate 14 and the outer tank 101 , and the torsion spring and the limit block drive the inner sealing plate 14 to be located at the inlet and outlet of the bottom surface of the outer tank 101 .

[0053] The present invention is provided with a temperature regulating assembly. When the gas storage tank 1 is transported to the destination and prepared for desorption, the temperature regulating assembly is installed in the gas storage tank 1. In the early stage, the pressure in the gas storage tank 1 is relatively high, the desorption rate of the coalbed methane is relatively high, and the coalbed methane output from the gas outlet pipe 3 can meet normal use. At this time, the pressure in the gas storage tank 1 is much higher than the atmospheric pressure, and the water 12 in the liquid storage section of the temperature regulating shell 8 will not flow out. As the coalbed methane is used, the pressure in the gas storage tank 1 gradually decreases, the desorption rate of the coalbed methane decreases, and the coalbed methane output from the gas outlet pipe 3 cannot meet normal use. When the pressure in the gas storage tank 1 is close to or lower than the atmospheric pressure, the water 12 in the liquid storage section of the temperature regulating shell 8 flows into the drug storage section through the liquid guide pipe 11. The water 12 encounters the quicklime 13 stored in the drug storage section to generate heat, which increases the temperature of the adsorption medium 4, thereby reducing the saturated adsorption capacity of the adsorption medium 4 and indirectly increasing the desorption rate of the coalbed methane, so that the coalbed methane output from the gas outlet pipe 3 can meet normal use.

[0054] In order to enable the temperature regulating shell 8 to drive the inner sealing plate 14 to rotate, a concave spiral slide 17 is provided on the lower surface of the inner sealing plate 14. The center of the circle where the slide 17 is located is located at the transition between the inner sealing plate 14 and the bottom surface of the outer tank 101. The lower end of the slide 17 is connected to the lower surface of the inner sealing plate 14, and the upper end is connected to the side wall of the inner sealing plate 14. A stopper 15 is sealed at the connection between the upper end of the slide 17 and the side wall of the inner sealing plate 14. The upper part of the stopper 15 is hinged to the inner sealing plate 14 by a torsion spring, and the torsion spring drives the stopper 15 to seal and fit the side wall of the inner sealing plate 14;

[0055] The top surface of the temperature regulating shell 8 is an outwardly convex arc surface, and a guide rod 16 is vertically fixed outside the top surface of the temperature regulating shell 8. The upper end of the guide rod 16 is an outwardly convex hemispherical shape and is arranged corresponding to the slide 17 of the inner sealing plate 14; when the temperature regulating shell 8 enters the inlet and outlet of the outer tank 101, the upper end of the guide rod 16 slides and is embedded in the slide 17 of the inner sealing plate 14.

[0056] In order to prevent the temperature regulating shell 8 from rotating when placed, a positioning sleeve 18 is fixedly provided on the outside of the inlet and outlet of the outer tank 101, and a positioning strip is longitudinally provided on the inner wall of the positioning sleeve 18. The lower end of the positioning sleeve 18 is sealed and detachably provided with an outer sealing plate 19, and a bottom plate 20 is detachably provided at the lower part of the temperature regulating shell 8. Positioning grooves corresponding to the positioning strips are provided on the outside of the temperature regulating shell 8 and the outside of the bottom plate 20.

[0057] In addition, the inlet and outlet of the bottom surface of the outer tank 101 of the present invention are provided with an inner sealing plate 14. The inner sealing plate 14 is located inside the outer tank 101. The pressure inside the gas tank 1 presses the inner sealing plate 14 against the outer tank 101, ensuring the airtightness of the gas tank 1. Simultaneously, a slide 17 is provided on the lower surface of the inner sealing plate 14, and a guide rod 16 is provided on the top surface of the temperature-regulating shell 8. When the temperature-regulating shell 8 is placed into the gas tank 1, the upper end of the guide rod 16 abuts the bottom surface of the slide 17. When the temperature-regulating shell 8 moves into the gas tank 1, the guide rod 16 moves vertically, causing the inner sealing plate 14 to move to one side and open. This process of opening the inner sealing plate 14 does not require any other power, which not only ensures the airtightness but also avoids the use of electricity, which could cause accidental ignition and explosion, thus ensuring safety.

[0058] To further optimize the product structure and improve practicality, the pressure reduction and desorption coalbed methane device also includes a base 21, and a plurality of gas storage tanks 1 are arranged on the upper part of the base 21, and both sides of the middle part of the gas storage tanks 1 are rotatably connected to the base 21.

[0059] In order to prevent the adsorption medium 4 from falling from the inner tank 102 when it is turned over, a partition net 22 is horizontally arranged on the upper part of the inner tank 102, and the adsorption medium 4 is filled between the partition net 22 and the bottom surface of the inner tank 102. The adsorption medium 4 includes but is not limited to solid materials such as activated carbon, molecular sieve, bentonite, etc. The partition net 22 prevents the adsorption medium 4 from falling from the inner tank 102 and does not hinder the passage of coalbed methane.

[0060] The base 21 is provided with a hydraulic cylinder 23. The number of hydraulic cylinders 23 is equal to that of the gas tank 1 and they are arranged one-to-one. The hydraulic cylinder 23 is located below the gas tank 1. The piston rod of the hydraulic cylinder 23 extends vertically upward and a transducer 24 is fixedly provided at the end of the piston rod. The upper surface of the transducer 24 is against the lower surface of the gas tank 1. The transducer 24 is connected to the ultrasonic generator 25.

[0061] The gas storage tank 1 of the present invention is rotatably arranged above the base 21. When placing the temperature regulating shell 8, the gas storage tank 1 is turned 180 degrees so that the bottom surface of the outer tank 101 faces upward, and the temperature regulating shell 8 is placed in a state where the liquid storage section is located at the lower end and the gas storage tank 1 is installed, so as to prevent the water 12 in the liquid storage section from entering the medicine storage section and facilitate operation. After the temperature regulating shell 8 is installed, the gas storage tank 1 is turned 180 degrees again, and the pressure in the liquid storage section prevents the water 12 from flowing out of the liquid storage section. At this time, the piston rod of the hydraulic cylinder 23 rises and reaches the gas storage tank 1, so that the gas storage tank 1 is in a stable state.

[0062] Under the action of sound waves, the diffusion coefficient of coalbed methane increases, and this coefficient increases with higher sound intensity. Therefore, sound waves increase the diffusion rate of coalbed methane. Under the action of sound waves, the diffusion resistance within the adsorption medium 4 is reduced, the diffusion capacity is enhanced, and the mass transfer rate is accelerated. Simultaneously, the sound waves gradually increase the temperature of the adsorption medium 4, reducing the saturated adsorption capacity of the adsorption medium 4. Used in conjunction with the temperature control component, this ensures that the coalbed methane output from the gas outlet pipe 3 is in a state sufficient for normal use. Ultrasonic waves will not cause coalbed methane explosions, ensuring safe and reliable use.

[0063] Finally, it should be noted that the above are only preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or make equivalent replacements for some of the technical features therein. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A decompression and desorption device for coalbed methane, characterized in that: The decompression and desorption coalbed methane device comprises a gas storage tank (1) and a pressure regulating mechanism, wherein the gas storage tank (1) comprises an outer tank (101) and an inner tank (102), wherein the outer tank (101) is in the shape of a hollow shell, and the inner tank (102) is in the shape of a shell with an upper end open and fixedly arranged in the outer tank (101), and gaps are left between each outer wall of the inner tank (102) and each inner wall of the outer tank (101), and an air inlet pipe (2) and an air outlet pipe (3) are arranged at the top of the outer tank (101), and the upper ends of the air inlet pipe (2) and the air outlet pipe (3) extend out of the outer tank (101), and the lower end of the air inlet pipe (2) extends into the bottom of the inner tank (102), and the lower end of the air outlet pipe (3) is located in the gap between the top of the outer tank (101) and the upper opening of the inner tank (102), and the inner tank (102) is filled with an adsorption medium (4); The pressure regulating mechanism comprises a piston plate (5), which is in the shape of an annular flat plate and is located between the peripheral outer wall of the inner tank (102) and the peripheral inner wall of the outer tank (101), and the inner side and the outer side of the piston plate (5) are respectively sealed and longitudinally slidably connected to the peripheral outer wall of the inner tank (102) and the peripheral inner wall of the outer tank (101).

2. A decompression and desorption coalbed methane device according to claim 1, characterized in that: A positioning group is arranged between the outer wall of the inner tank (102) and the inner wall of the outer tank (101). There are two positioning groups, which are respectively located at the upper part and the lower part of the inner tank (102). The positioning group includes a plurality of positioning plates (6) arranged in a circular array. The inner and outer sides of the positioning plates (6) are respectively fixedly connected to the inner tank (102) and the outer tank (101). The piston plate (5) is located between the two positioning groups.

3. The decompression and desorption coalbed methane device according to claim 1, characterized in that: The decompression and desorption coalbed methane device also includes a temperature control component for adjusting the temperature of the adsorption medium (4); the bottom surface of the inner tank (102) is provided with a concave temperature control chamber (7); the temperature control chamber (7) is vertically arranged and the lower end is connected to the gap formed between the bottom surface of the outer tank (101) and the bottom surface of the inner tank (102); the temperature control component is arranged in the temperature control chamber (7).

4. A decompression and desorption device for coalbed methane according to claim 3, characterized in that: The temperature control component comprises a temperature control shell (8), the upper part of the temperature control shell (8) is a shell having an opening at the lower end corresponding to the shape of the temperature control bin (7), and the outer wall of the temperature control shell (8) is thermally bonded to the inner wall of the temperature control bin (7); An upper partition (9) and a lower partition (10) are transversely arranged at the upper and lower parts of the temperature regulating shell (8), respectively. The upper partition (9) and the lower partition (10) divide the internal space of the temperature regulating shell (8) into a liquid storage section, a medicine storage section and a connecting section from top to bottom. A liquid guide tube (11) is longitudinally arranged in the medicine storage section. The upper and lower ends of the liquid guide tube (11) are connected to the liquid storage section and the connecting section respectively. The outer wall of the liquid guide tube (11) is uniformly distributed with micropores. The liquid storage section stores water (12), the medicine storage section stores quicklime (13), and the connecting section is connected to the gap formed between the bottom surface of the outer tank (101) and the bottom surface of the inner tank (102).

5. A decompression and desorption device for coalbed methane according to claim 4, characterized in that: The bottom surface of the outer tank (101) is provided with an inlet and an outlet, the inlet and an outlet are located directly below the temperature regulating chamber (7) and have the same shape as the cross-section of the inner wall of the temperature regulating chamber (7), and an inner sealing plate (14) is provided at the inlet and an outlet for sealing, the inner sealing plate (14) is located in the outer tank (101) and one side of the inner sealing plate is rotatably connected to the bottom surface of the outer tank (101); A torsion spring and a limit block are provided between the inner sealing plate (14) and the outer tank (101), and the torsion spring and the limit block drive the inner sealing plate (14) to be located at the inlet and outlet of the bottom surface of the outer tank (101).

6. A decompression and desorption device for coalbed methane according to claim 5, characterized in that: The lower surface of the inner sealing plate (14) is provided with an inwardly concave spiral slideway (17), the center of the circle where the slideway (17) is located is located at the transition point between the inner sealing plate (14) and the bottom surface of the outer tank (101), the lower end of the slideway (17) is connected to the lower surface of the inner sealing plate (14), and the upper end is connected to the side wall of the inner sealing plate (14), and a stopper (15) is sealed at the connection point between the upper end of the slideway (17) and the side wall of the inner sealing plate (14), and the upper part of the stopper (15) is hinged to the inner sealing plate (14) through a torsion spring, and the torsion spring drives the stopper (15) to seal and fit the side wall of the inner sealing plate (14); The top surface of the temperature regulating shell (8) is an outwardly convex arc surface, and a guide rod (16) is vertically fixedly arranged outside the top surface of the temperature regulating shell (8). The upper end of the guide rod (16) is in an outwardly convex hemispherical shape and is arranged corresponding to the slideway (17) of the inner sealing plate (14); when the temperature regulating shell (8) enters the inlet and outlet of the outer tank (101), the upper end of the guide rod (16) slides and fits into the slideway (17) of the inner sealing plate (14).

7. A decompression and desorption device for coalbed methane according to claim 6, characterized in that: A positioning sleeve (18) is fixedly provided on the outer side of the inlet and outlet of the outer tank (101), a positioning strip is longitudinally provided on the inner wall of the positioning sleeve (18), an outer sealing plate (19) is detachably provided at the lower end of the positioning sleeve (18), a bottom plate (20) is detachably provided at the lower part of the temperature regulating shell (8), and positioning grooves corresponding to the positioning strip are provided on the outer side of the temperature regulating shell (8) and the outer side of the bottom plate (20).

8. A decompression and desorption coalbed methane device according to any one of claims 5 to 7, characterized in that: The decompression and desorption coalbed methane device also includes a base (21), a plurality of gas storage tanks (1) are arranged on the upper part of the base (21), and both sides of the middle part of the gas storage tanks (1) are rotatably connected to the base (21).

9. A decompression and desorption device for coal bed methane according to claim 8, characterized in that: A partition (22) is laterally arranged at the upper inner portion of the inner tank (102), and the adsorption medium (4) is filled between the partition (22) and the bottom surface of the inner tank (102). The adsorption medium (4) includes but is not limited to solid materials such as activated carbon, molecular sieve, bentonite, etc. The partition (22) prevents the adsorption medium (4) from falling from the inner tank (102) and does not hinder the passage of coalbed methane.

10. The device for reducing pressure and desorbing coalbed methane according to claim 8, characterized in that: The base (21) is provided with a hydraulic cylinder (23), the number of the hydraulic cylinders (23) is equal to that of the gas storage tank (1) and they are arranged one-to-one, the hydraulic cylinder (23) is located below the gas storage tank (1), the piston rod of the hydraulic cylinder (23) extends vertically upward and a transducer (24) is fixedly arranged at the end of the piston rod, the upper surface of the transducer (24) abuts against the lower surface of the gas storage tank (1), and the transducer (24) is connected to an ultrasonic generator (25).

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