Coal bed gas yield increasing system and method for driving compressor to heat coal bed through solar energy

Abstract

The invention discloses a coal bed gas yield increasing system and method for driving a compressor to heat a coal bed through solar energy. The production well, the horizontal well and the injection well are sequentially communicated to form a U-shaped well structure. An outlet of the production well is connected to the input end of the storage tank through a first valve, and the first output end and the second output end of the storage tank are connected to the input end of the purification device and the first input end of the compressor through a third valve and a fourth valve respectively. The output end of the solar driving unit is connected to the second input end of the compressor, and the output end of the compressor is connected to an inlet of the injection well through a second valve; and the plurality of temperature and pressure monitors are respectively arranged at the inlet of the injection well, the intersection of the injection well and the horizontal well, the middle part of the horizontal well and the bottom of the production well. The system utilizes solar energy to drive the compressor to heat the coal bed, the temperature of the coal bed is effectively increased, methane desorption is promoted, the coal bed gas yield is increased, and dynamic adjustment of gas flow directions under different working conditions is achieved through intelligent control valve switching.

Description

Technical Field

[0001] This application relates to the field of coalbed methane development, and particularly to a coalbed methane production increase system and method for heating coal seams by using a solar-powered compressor. Background Art

[0002] As a key development target, coalbed methane is becoming increasingly important in the global energy market. From an environmental protection perspective, the development of coalbed methane is of great significance for reducing greenhouse gas emissions. The carbon dioxide emissions generated by its combustion are much lower than those of coal, which plays a significant role in slowing down climate change. At the same time, it can effectively reduce coal mine gas disasters and improve the environmental safety level of mining areas. However, there are many problems with existing coalbed methane production methods by injecting heat: the steam injection method causes a decrease in gas-phase permeability due to condensation, large energy losses, and is prone to water lock damage; although the carbon dioxide injection method has obvious advantages, its technical considerations are complex; the microwave injection method faces technical problems such as well entry, transmission loss, and radiation radius; the in-situ combustion method has problems such as difficult ignition, serious pollution, poor wellbore stability, and difficult combustion control in coal seam applications. Summary of the Invention

[0003] The embodiments of this application solve the problems raised in the background art by providing a coalbed methane production increase system and method for heating coal seams by using a solar-powered compressor.

[0004] In a first aspect, the embodiments of this application provide a coalbed methane production increase system for heating coal seams by using a solar-powered compressor, including a production well, a horizontal well, an injection well, a storage tank, a solar-powered unit, a compressor, a controller, and multiple temperature and pressure monitors; the production well, the horizontal well, and the injection well are connected in sequence to form a U-shaped well structure; wherein, the production well and the injection well are vertical wells, and their bottoms both extend to the middle area of the coal reservoir; the horizontal well is located in the middle of the coal reservoir and connects the bottoms of the production well and the injection well; the outlet of the production well is connected to the input end of the storage tank through a first valve, and the first output end and the second output end of the storage tank are respectively connected to the input end of the purification device and the first input end of the compressor through a third valve and a fourth valve; the output end of the solar-powered unit is connected to the second input end of the compressor, and the output end of the compressor is connected to the inlet of the injection well through a second valve; multiple temperature and pressure monitors are respectively arranged at the inlet of the injection well, the intersection of the injection well and the horizontal well, the middle of the horizontal well, and the bottom of the production well; the controller is communicatively connected to the temperature and pressure monitors, the compressor, the first valve, the second valve, the third valve, and the fourth valve.

[0005] In combination with the first aspect, in a possible implementation manner, the coalbed methane production increase system for heating a coal seam by using a solar energy-driven compressor further includes a gas pretreatment device; the input end of the gas pretreatment device is connected to the first valve, and its output end is connected to the input end of the storage tank.

[0006] In combination with the first aspect, in a possible implementation manner, the gas pretreatment device includes a cyclone separator and a dehydration module; the input end of the cyclone separator is connected to the first valve, its output end is connected to the input end of the dehydration module, and the output end of the dehydration module is connected to the input end of the storage tank; the cyclone separator is used to remove solid particles in the coalbed methane; the dehydration module is used to remove tar.

[0007] In combination with the first aspect, in a possible implementation manner, the solar energy driving unit includes a photovoltaic panel and an inverter; the photovoltaic panel is connected to the input end of the inverter, and the first output end of the inverter is connected to the second input end of the compressor.

[0008] In combination with the first aspect, in a possible implementation manner, the solar energy driving unit further includes an energy storage device; the input end of the energy storage device is connected to the second output end of the inverter, and its output end is connected to the second input end of the compressor.

[0009] In the second aspect, an embodiment of the present application provides a method for increasing coalbed methane production by using a solar energy-driven compressor to heat a coal seam, including the coalbed methane production increase system for heating a coal seam by using a solar energy-driven compressor according to the first aspect or any possible implementation manner of the first aspect. The method includes: S1: Drill a vertical injection well to the middle of the coal reservoir, and then drill a production well to the middle of the coal reservoir. Horizontally drill from the bottom of the production well to the bottom of the injection well to form a horizontal well located in the middle area of the coal reservoir; S2: During the mining period or the period without sunlight, the controller opens the first valve and the third valve, and closes the second valve and the fourth valve; store the gas produced by the production well in the storage tank, and part of the gas is output to the user end through the purification device; S3: During the sunlight period, when the controller detects that the sunlight intensity ≥ 500 W / m², close the first valve and the third valve, open the second valve and the fourth valve, start the solar energy driving unit and the compressor, pressurize and heat the gas in the storage tank and then transport it to the injection well; the high-temperature and high-pressure gas heats the coal reservoir through the horizontal well, promotes the desorption of adsorbed methane, and the desorbed gas is produced through the production well; S4: During the execution of S3 in the sunlight period, the controller monitors the temperature in the middle of the horizontal well and the pressure at the bottom of the production well in real time: If the temperature in the middle of the horizontal well is lower than 60% of the highest temperature during the current illumination period, or the bottom pressure of the production well is less than 60% of the set threshold, the controller will open the first valve, while keeping the fourth valve and the second valve open and the third valve closed; Continuously pressurize and heat the gas in the storage tank and inject it into the coal reservoir, and at the same time store the newly produced gas from the production well in the storage tank until the end of the current illumination period; S5: At the end of the current illumination period: The controller opens the first valve and the third valve, and closes the second valve and the fourth valve; Store the gas produced by the production well in the storage tank, and part of the gas is output to the user side through the purification device; S6: Repeat S2 - S5 until the methane concentration of the produced gas < 5% to terminate the cycle.

[0010] Combined with the second aspect, in a possible implementation, in S3, the gas temperature at the output end of the compressor is 90 - 120 °C, and the pressure is 2 - 5 MPa higher than the formation pressure.

[0011] Combined with the second aspect, in a possible implementation, S2 further includes storing the gas produced by the production well in the storage tank after being processed by the gas pretreatment device to remove solid particles and tar in the gas produced by the production well.

[0012] Combined with the second aspect, in a possible implementation, in S4, the set threshold is the bottom pressure value of the production well at the end of the previous illumination period.

[0013] One or more technical solutions provided in the embodiments of the present application have at least the following technical effects: When the coalbed methane production increase system of the present application works, first drill injection wells and production wells and form horizontal wells to build a gas production channel; during the mining period or the non - illumination period, the controller adjusts the valves to store the gas from the production well in the storage tank and output part of it; during the illumination period, the controller switches the valve states according to the illumination intensity, starts the solar - driven unit and the compressor, pressurize and heat the gas in the storage tank and inject it into the coal reservoir, and use the high - temperature and high - pressure gas to heat the coal reservoir to promote methane desorption; during this period, the temperature in the middle of the horizontal well and the bottom pressure of the production well are monitored in real time. If the temperature or pressure is lower than the set value, adjust the valve state and continue to pressurize and inject gas; restore the initial valve state at the end of the illumination period. On the one hand, this system makes full use of solar energy resources, reduces the dependence on traditional energy, and realizes green and energy - saving gas production; on the other hand, by precisely controlling the valves and the operation of equipment, optimizing the gas circulation and heating process, it effectively promotes the desorption of adsorbed methane in the coal reservoir, improves the recovery rate of methane, and terminates the cycle until the methane concentration of the produced gas is lower than 5%, realizing efficient and sustainable coalbed methane exploitation. Description of the Drawings

[0014] To more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the accompanying drawings required for the description of the embodiments of the present application. Obviously, the accompanying drawings in the following description are some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can also be obtained based on these drawings.

[0015] Figure 1 It is a schematic structural diagram of a coalbed methane production-increasing system for heating a coal seam by using a solar-driven compressor provided in an embodiment of the present application; Figure 2 It is a schematic diagram showing the change of the adsorption amount of methane in coalbed methane with temperature provided in an embodiment of the present application.

[0016] Reference numerals: 1 - production well; 11 - first valve; 2 - horizontal well; 3 - injection well; 31 - second valve; 4 - storage tank; 41 - third valve; 42 - fourth valve; 5 - solar-driven unit; 51 - photovoltaic panel; 52 - inverter; 53 - energy storage device; 6 - compressor; 7 - purification device; 8 - gas pretreatment device; 9 - coal reservoir; 10 - rock formation. Detailed implementation manners

[0017] The following will clearly and completely describe the technical solutions in the embodiments of the present application in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are some, but not all, of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present application.

[0018] In the description of the embodiments of the present application, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the embodiments of the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present application. The terms "first", "second", "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance. In addition, the terms "installation", "connection", "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the internal communication of two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to specific circumstances.

[0019] An embodiment of the present application provides a coalbed methane production increase system that uses solar energy to drive a compressor to heat a coal seam, as Figure 1 shown. The coalbed methane production increase system that uses solar energy to drive a compressor to heat a coal seam includes a production well 1, a horizontal well 2, an injection well 3, a storage tank 4, a solar energy driving unit 5, a compressor 6, a controller, and multiple temperature and pressure monitors; the production well 1, the horizontal well 2, and the injection well 3 are connected in sequence to form a U-shaped well structure; wherein, the production well 1 and the injection well 3 are vertical wells, and their bottoms both extend to the middle area of the coal reservoir 9; the horizontal well 2 is located in the middle of the coal reservoir 9 and connects the bottoms of the production well 1 and the injection well 3. The coal reservoir 9 is located below the rock formation 10.

[0020] Preferably, the distance between the top of the horizontal well 2 of the present application and the roof of the coal reservoir 9 should be controlled between 0.5 - 2 m. The distance between the top of the horizontal well 2 and the roof of the coal reservoir 9 being 0.5 - 2 m can make the heat transfer to the coal reservoir 9 more uniform and efficient. If the distance is too close, the properties of the coal reservoir 9 may change due to excessive local temperature, affecting the uniformity of heat conduction; if the distance is too far, the heat loss increases during the transfer process, and the coal seam cannot be effectively heated. This distance range can ensure that the heat fully acts on the coal seam, making more adsorbed methane desorb into free state, and improving the desorption efficiency of coalbed methane. A reasonable distance helps the desorbed coalbed methane to diffuse better in the pores of the coal seam. When the distance is between 0.5 - 2 m, the gas diffusion channel is relatively smooth, and the gas can flow rapidly towards the production well 1 direction, reducing the residence time of the gas in the coal reservoir 9, thereby improving the production efficiency of coalbed methane.

[0021] The outlet of the production well 1 is connected to the input end of the storage tank 4 through a first valve 11, and the first output end and the second output end of the storage tank 4 are respectively connected to the input end of the purification device 7 and the first input end of the compressor 6 through a third valve 41 and a fourth valve 42; the output end of the solar energy driving unit 5 is connected to the second input end of the compressor 6, and the output end of the compressor 6 is connected to the inlet of the injection well 3 through a second valve 31; multiple temperature and pressure monitors are respectively arranged at the inlet of the injection well 3, the intersection of the injection well 3 and the horizontal well 2, the middle of the horizontal well 2, and the bottom of the production well 1; the controller is communicatively connected to the temperature and pressure monitors, the compressor 6, the first valve 11, the second valve 31, the third valve 41, and the fourth valve 42.

[0022] Specifically, packers are provided on the outer walls of the well pipes of the production well 1 and the horizontal well 2.

[0023] It should be noted that when the coalbed methane production enhancement system of the present application operates, injection wells 3 and production wells 1 are first drilled and horizontal wells 2 are formed to construct a gas production channel. During the exploitation period or the period without sunlight, the controller adjusts the valve to store the gas in the production well 1 in the storage tank 4 and partially output it. During the sunlight period, the controller switches the valve state according to the sunlight intensity, starts the solar energy drive unit 5 and the compressor 6, pressurizes and heats the gas in the storage tank 4 and then injects it into the coal reservoir 9. The high-temperature and high-pressure gas is used to heat the coal reservoir 9 to promote methane desorption. During this period, the temperature in the middle of the horizontal well 2 and the pressure at the bottom of the production well 1 are monitored in real time. If the temperature or pressure is lower than the set value, the valve state is adjusted to continue pressurized gas injection. At the end of the sunlight period, the initial valve state is restored. On the one hand, this system makes full use of solar energy resources, reduces the dependence on traditional energy sources, and realizes green and energy-saving gas production. On the other hand, by precisely controlling the valve and equipment operation, optimizing the gas circulation and heating process, it effectively promotes the desorption of adsorbed methane in the coal reservoir 9, improves the recovery rate of methane, and terminates the cycle until the methane concentration in the produced gas is lower than 5%, realizing efficient and sustainable coalbed methane exploitation.

[0024] In the embodiment of the present application, the coalbed methane production enhancement system that uses solar energy to drive a compressor to heat the coal seam further includes a gas pretreatment device 8. The input end of the gas pretreatment device 8 is connected to the first valve 11, and its output end is connected to the input end of the storage tank 4.

[0025] In the embodiment of the present application, the gas pretreatment device 8 includes a cyclone separator and a dehydration module. The input end of the cyclone separator is connected to the first valve 11, its output end is connected to the input end of the dehydration module, and the output end of the dehydration module is connected to the input end of the storage tank 4. The cyclone separator is used to remove solid particles in the coalbed methane, and the dehydration module is used to remove tar.

[0026] In the embodiment of the present application, a gas pretreatment device 8 is arranged on the path of transporting the gas in the production well 1 to the storage tank 4. When the gas produced by the production well 1 flows out through the first valve 11, it first enters the cyclone separator, and the solid particles in the coalbed methane are separated and removed by the centrifugal force generated by the cyclone. Subsequently, the gas enters the dehydration module, and the tar in it is removed through a specific dehydration process. The purified gas after treatment then enters the storage tank 4 for storage. This gas pretreatment device 8 effectively purifies the coalbed methane, avoids damage such as abrasion, blockage, and corrosion to subsequent equipment such as the compressor 6 and pipelines caused by solid particles and tar, ensures the stable operation of the system, extends the service life of the equipment, improves the quality of the coalbed methane at the same time, reduces the subsequent purification treatment burden, and enhances the reliability and economy of the entire production enhancement system.

[0027] In the embodiment of the present application, the solar energy drive unit 5 includes a photovoltaic panel 51 and an inverter 52. The photovoltaic panel 51 is connected to the input end of the inverter 52, and the first output end of the inverter 52 is connected to the second input end of the compressor 6.

[0028] In the embodiment of the present application, the solar driving unit 5 further includes an energy storage device 53; the input end of the energy storage device 53 is connected to the second output end of the inverter 52, and its output end is connected to the second input end of the compressor 6.

[0029] In the embodiment of the present application, when the solar driving unit 5 operates, the photovoltaic panel 51 converts solar energy into direct current and transmits it to the inverter 52. On the one hand, the inverter 52 converts the direct current into alternating current with appropriate parameters through the first output end and directly supplies it to the motor of the compressor 6 to drive its operation; on the other hand, the excess electric energy is transmitted to the energy storage device 53 through the second output end for storage; when the light is insufficient or the instantaneous power demand of the compressor 6 is large, the energy storage device 53 releases the stored electric energy, and supplies power to the compressor 6 together with the electric energy converted by the inverter 52 in real time to ensure its stable operation; the solar driving unit 5 efficiently utilizes solar energy through the photovoltaic panel 51, combines the energy storage device 53 to realize the storage and flexible allocation of electric energy, effectively solves the problem of solar intermittency, ensures that the compressor 6 can obtain continuous and stable power supply under various working conditions, improves the reliability of system operation and energy utilization efficiency, and at the same time reduces the dependence on traditional energy sources, having significant energy-saving and environmental protection benefits.

[0030] The embodiment of the present application provides a method for increasing the production of coalbed methane by using solar energy to drive a compressor to heat a coal seam, including the above-mentioned system for increasing the production of coalbed methane by using solar energy to drive a compressor to heat a coal seam, and the method includes: S1: Drill a vertical injection well 3 to the middle of the coal reservoir 9, and then drill a production well 1 to the middle of the coal reservoir 9, and horizontally drill from the bottom of the production well 1 to the bottom of the injection well 3 to form a horizontal well 2 in the middle area of the coal reservoir 9; S2: During the mining period or the period without light, the controller opens the first valve 11 and the third valve 41, and closes the second valve 31 and the fourth valve 42; store the gas produced by the production well 1 in the storage tank 4, and part of the gas is output to the user end through the purification device 7; S3: During the light period, when the controller detects that the light intensity ≥ 500 W / m², close the first valve 11 and the third valve 41, open the second valve 31 and the fourth valve 42, start the solar driving unit 5 and the compressor 6, pressurize and heat the gas in the storage tank 4 and then transport it to the injection well 3; the high-temperature and high-pressure gas heats the coal reservoir 9 through the horizontal well 2, promotes the desorption of adsorbed methane, and the desorbed gas is produced through the production well 1; It should be noted that when the temperature in the middle of the horizontal well 2 is lower than 60% of the highest temperature during this light period, continue to inject gas until the end of the light period to avoid waste of solar energy resources.

[0031] S4: During the execution of S3 in the light period, the controller monitors the temperature in the middle of the horizontal well 2 and the pressure at the bottom of the production well 1 in real time: If the temperature in the middle of the horizontal well 2 is lower than 60% of the highest temperature during the current light period, or the bottom pressure of the production well 1 is less than 60% of the set threshold, the controller will open the first valve 11, while keeping the fourth valve 42 and the second valve 31 open and the third valve 41 closed; Continuously pressurize and heat the gas in the storage tank 4 and inject it into the coal reservoir 9, while storing the newly produced gas from the production well 1 into the storage tank 4 until the end of the current light period; S5: At the end of the current light period: The controller opens the first valve 11 and the third valve 41, and closes the second valve 31 and the fourth valve 42; Store the gas produced by the production well 1 into the storage tank 4, and part of the gas is output to the user side through the purification device 7; S6: Repeat S2 - S5 until the methane concentration in the produced gas < 5% to terminate the cycle.

[0032] In the coalbed methane production increase method of the embodiment of the present application, by first constructing a U-shaped well structure, during the mining period or the non-light period, the controller controls the valves to store the gas from the production well 1 into the storage tank 4 and supply part of it to the user; when the light reaches the standard during the light period, the valves are switched, and the solar energy driving unit 5 (the photovoltaic panel 51 generates electricity and the energy storage device 53 assists) is started to drive the compressor 6. The gas in the storage tank 4 is pressurized and heated to appropriate parameters and then injected into the injection well 3. The high-temperature and high-pressure gas heats the coal reservoir 9 through the horizontal well 2, breaking the adsorption equilibrium and promoting methane desorption and production. This method uses solar energy to drive the compressor 6 to accurately control the injection gas parameters, effectively heats the coal seam to improve the methane desorption efficiency, and significantly increases the coalbed methane production; through intelligent valve switching and real-time monitoring, flexible conversion of different working conditions is realized, ensuring the stable and efficient operation of the system, while making full use of clean energy, reducing the mining cost and carbon emissions.

[0033] In the embodiment of the present application, in S3, the gas temperature at the output end of the compressor 6 is 90 - 120 °C, and the pressure is 2 - 5 MPa higher than the formation pressure. The formation pressure varies depending on the depth of the coal reservoir 9.

[0034] As Figure 2As shown, from the perspective of methane desorption, when the temperature > 80°C, the adsorption capacity of methane in the coal seam decreases significantly, and the desorption rate increases significantly. In this temperature range, high-temperature and high-pressure gas can more effectively break the adsorption equilibrium of methane in coal reservoir 9, making it easier for methane molecules originally adsorbed on the pore surface of coal reservoir 9 to break free from the bondage and transform from the adsorbed state to the free state, thereby greatly improving the desorption efficiency of coalbed methane and increasing the output of coalbed methane. At the same time, precisely controlling the temperature in the range of 90 - 120°C can effectively avoid the problem of coal oxidation and spontaneous combustion caused by too high temperature. The oxidation and spontaneous combustion of coal will not only damage the structure of coal reservoir 9 and affect the coalbed methane mining environment, but also may cause safety accidents and threaten the safety of mining equipment and personnel. By reasonably controlling the temperature, while ensuring the efficient desorption of methane, it provides a safe and stable working environment for the coalbed methane mining process, ensures that the entire production-increasing system can operate continuously and stably, improves the safety and reliability of mining, and reduces the mining risk and cost.

[0035] In addition, the pressure at the output end of the compressor 6 is greater than the pressure at the bottom of the well. In the embodiment of the present application, S2 further includes storing the gas produced by the production well 1 in the storage tank 4 after being processed by the gas pretreatment device 8 to remove solid particles and tar in the gas produced by the production well 1.

[0036] In the embodiment of the present application, in S4, the set threshold value is the bottom pressure value of the production well 1 at the end of the previous illumination period.

[0037] It should be noted that setting the set threshold value as the bottom pressure value of the production well 1 at the end of the previous illumination period, this dynamic setting method can accurately reflect the pressure change characteristics of the coal reservoir 9 under different illumination cycles, enabling the system to flexibly switch working conditions according to the actual pressure condition of the coal reservoir 9 during the mining process, preventing the gas production efficiency from decreasing due to too low pressure and avoiding potential safety hazards caused by too high pressure, ensuring the efficiency, stability and safety of the coalbed methane mining process, and improving the reliability and economy of the entire production-increasing system.

[0038] The various embodiments in this specification are described in a progressive manner. For the same or similar parts between the various embodiments, reference can be made to each other. Each embodiment focuses on the differences from other embodiments.

[0039] The above embodiments are only used to illustrate the technical solutions of the present application, rather than limiting the present application. Although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the present application.

Claims

1. A coalbed methane production-increasing system that uses solar energy to drive a compressor to heat a coal seam, characterized in that, It includes a production well (1), a horizontal well (2), an injection well (3), a storage tank (4), a solar-driven unit (5), a compressor (6), a controller, and multiple temperature and pressure monitors; The production well (1), the horizontal well (2), and the injection well (3) are connected in sequence to form a U-shaped well structure; wherein, the production well (1) and the injection well (3) are vertical wells, and their bottoms both extend to the middle area of the coal reservoir (9); the horizontal well (2) is located in the middle of the coal reservoir (9) and connects the bottoms of the production well (1) and the injection well (3); The outlet of the production well (1) is connected to the input end of the storage tank (4) through a first valve (11), and the first output end and the second output end of the storage tank (4) are respectively connected to the input end of a purification device (7) and the first input end of the compressor (6) through a third valve (41) and a fourth valve (42); The output end of the solar-driven unit (5) is connected to the second input end of the compressor (6), and the output end of the compressor (6) is connected to the inlet of the injection well (3) through a second valve (31); Multiple temperature and pressure monitors are respectively arranged at the inlet of the injection well (3), the intersection of the injection well (3) and the horizontal well (2), the middle of the horizontal well (2), and the bottom of the production well (1); The controller is communicatively connected to the temperature and pressure monitors, the compressor (6), the first valve (11), the second valve (31), the third valve (41), and the fourth valve (42).

2. The coalbed methane production-increasing system for heating a coal seam by using a solar energy-driven compressor according to claim 1, wherein, It further includes a gas pretreatment device (8); The input end of the gas pretreatment device (8) is connected to the first valve (11), and its output end is connected to the input end of the storage tank (4).

3. The coalbed methane production-increasing system for heating a coal seam by using a solar energy-driven compressor according to claim 2, wherein The gas pretreatment device (8) includes a cyclone separator and a dehydration module; The input end of the cyclone separator is connected to the first valve (11), its output end is connected to the input end of the dehydration module, and the output end of the dehydration module is connected to the input end of the storage tank (4); The cyclone separator is used to remove solid particles in the coalbed methane; the dehydration module is used to remove tar.

4. The coalbed methane production enhancement system for heating a coal seam by using a solar energy-driven compressor according to claim 1, wherein The solar-driven unit (5) includes a photovoltaic panel (51) and an inverter (52); The photovoltaic panel (51) is connected to the input end of the inverter (52), and the first output end of the inverter (52) is connected to the second input end of the compressor (6).

5. The coalbed methane production enhancement system for heating a coal seam by using a solar energy-driven compressor according to claim 4, wherein The solar-driven unit (5) further includes an energy storage device (53); The input end of the energy storage device (53) is connected to the second output end of the inverter (52), and its output end is connected to the second input end of the compressor (6).

6. A method for increasing the production of coalbed methane by using solar energy to drive a compressor to heat a coal seam, characterized in that, It includes a coalbed methane production increase system for heating coal seams by using a solar-driven compressor according to any one of claims 1-5, and the method includes: S1: Drill a vertical injection well (3) to the middle of the coal reservoir (9), and then drill a production well (1) to the middle of the coal reservoir (9). Horizontally drill from the bottom of the production well (1) to the bottom of the injection well (3) to form a horizontal well (2) in the middle area of the coal reservoir (9). S2: During the mining period or the period without sunlight, the controller opens the first valve (11) and the third valve (41), and closes the second valve (31) and the fourth valve (42); store the gas produced by the production well (1) in the storage tank (4), and part of the gas is output to the user end through the purification device (7). S3: During the sunlight period, when the controller detects that the sunlight intensity ≥ 500 W / m², close the first valve (11) and the third valve (41), open the second valve (31) and the fourth valve (42), start the solar drive unit (5) and the compressor (6), pressurize and heat the gas in the storage tank (4) and then transport it to the injection well (3); the high-temperature and high-pressure gas heats the coal reservoir (9) through the horizontal well (2) to promote the desorption of adsorbed methane, and the desorbed gas is produced through the production well (1). S4: During the process of executing S3 in the sunlight period, the controller monitors the temperature in the middle of the horizontal well (2) and the pressure at the bottom of the production well (1) in real time: If the temperature in the middle of the horizontal well (2) is lower than 60% of the highest temperature in this sunlight period, or the pressure at the bottom of the production well (1) is less than 60% of the set threshold, the controller will open the first valve (11), and at the same time keep the fourth valve (42) and the second valve (31) open, and the third valve (41) closed. Continuously pressurize and heat the gas in the storage tank (4) and inject it into the coal reservoir (9), and at the same time store the newly produced gas from the production well (1) in the storage tank (4) until the end of the current sunlight period. S5: When the current sunlight period ends: The controller opens the first valve (11) and the third valve (41), and closes the second valve (31) and the fourth valve (42); Store the gas produced by the production well (1) in the storage tank (4), and part of the gas is output to the user end through the purification device (7). S6: Repeat S2 - S5 until the methane concentration of the produced gas < 5% and then terminate the cycle.

7. The method according to claim 6, wherein In S3, the gas temperature at the output end of the compressor (6) is 90 - 120 °C, and the pressure is 2 - 5 MPa higher than the formation pressure.

8. The method according to claim 6, wherein S2 also includes treating the gas produced by the production well (1) through the gas pretreatment device (8) and then storing it in the storage tank (4) to remove solid particles and tar in the gas produced by the production well (1).

9. The method according to claim 6, wherein In S4, the set threshold is the bottom pressure value of the production well (1) at the end of the previous sunlight period.

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