Coal seam gas injection displacement extraction promotion monitoring system and regulation and control method

Abstract

The invention provides a coal seam gas injection displacement extraction promotion monitoring system and a regulation and control method, and the system comprises an extraction subsystem, a plurality of gas extraction ends of the extraction subsystem are respectively arranged in a coal seam, and the extraction subsystem is used for extracting first gas from the coal seam; a plurality of gas injection ends of the gas injection subsystem are arranged in the coal seam, and the gas injection subsystem is used for injecting second gas into the coal seam; and the monitoring subsystem is used for adjusting the pressure of the second gas according to the preset step pressure until the gas extraction pure flow in the first gas is within the flow range and the attenuation coefficient is within the coefficient range. According to the monitoring system and the regulation and control method for coal seam gas injection displacement and extraction promotion, effect monitoring and dynamic regulation of coal seam gas injection displacement and extraction promotion are achieved, so that the gas injection displacement and extraction promotion gas extraction efficiency is improved, and the real-time safety and high efficiency of a gas injection displacement technology are guaranteed.

Description

Technical Field

[0001] The present disclosure relates to the technical field of coal mine gas prevention and control, and particularly relates to a monitoring system and a regulation method for gas injection displacement and enhanced extraction of coal seam gas. Background Technique

[0002] As the ballast of energy supply, coal resources play an important strategic role in the economy. However, with the gradual depletion of traditional regional coal resources and the aggravation of disaster problems in recent years, the focus of coal resources is gradually shifting to new regions. The coal seams in the new regions are characterized by strong gas adsorption, poor permeability, and high gas unsaturation. Under the background of the intelligent intensive development of coal production capacity and the continuous increase in mining intensity, higher requirements are put forward for mine gas prevention and control. Traditional negative pressure extraction and coal seam modification and permeability enhancement technologies have poor extraction effects on solving the gas in such low gas-bearing coal seams.

[0003] The gas injection displacement and enhanced extraction technology, which injects high-energy and high-pressure gas into the coal seam and uses the dual effects of gas competitive adsorption and pressure drive to reduce the methane adsorption potential energy and enhance its fluidity, has been widely verified in recent years to effectively improve the gas extraction effect of low gas-bearing coal seams. However, in the process of on-site engineering application, the gas injection displacement and enhanced extraction technology has problems such as poor adaptability of gas injection parameters to coal seam occurrence, lag in monitoring the gas extraction effect of displacement and enhanced extraction, and rigid gas injection-extraction dynamic coordination regulation mode. In order to effectively monitor the gas extraction effect of gas injection displacement and improve the gas extraction efficiency of gas injection displacement and enhanced extraction, a monitoring system and a regulation method are proposed. Summary of the Invention

[0004] The present disclosure aims to solve at least one of the technical problems in the related technologies to some extent.

[0005] To this end, an object of the present disclosure is to provide a monitoring system and a regulation method for gas injection displacement and enhanced extraction of coal seam gas.

[0006] To achieve the above object, the first aspect of the present disclosure provides a monitoring system for gas injection displacement and enhanced extraction of coal seam gas, including: a extraction subsystem, multiple extraction ends of the extraction subsystem are respectively arranged in the coal seam, and the extraction subsystem is used to extract a first gas from the coal seam; an injection subsystem, multiple injection ends of the injection subsystem are respectively arranged in the coal seam, and the injection subsystem is used to inject a second gas into the coal seam; a monitoring subsystem, a communication end of the monitoring subsystem is respectively connected to a communication end of the extraction subsystem and a communication end of the injection subsystem, and the monitoring subsystem is used to adjust the pressure of the second gas according to a preset step pressure until the pure gas extraction flow rate of the gas in the first gas is within a flow rate range and the attenuation coefficient is within a coefficient range.

[0007] Optionally, the gas extraction subsystem includes: a plurality of gas extraction boreholes, a plurality of manifolds, a gas extraction branch pipe, and a plurality of gas extraction control valves; the plurality of gas extraction boreholes are respectively arranged in the coal seam, and the inlet ends of the manifolds are respectively connected to the outlet ends of the plurality of gas extraction boreholes, the inlet end of the gas extraction branch pipe is connected to the outlet ends of the plurality of manifolds, and the plurality of gas extraction control valves are respectively arranged between the inlet end of the gas extraction branch pipe and the outlet ends of the plurality of manifolds; the communication end of the monitoring subsystem is connected to the communication end of the gas extraction control valve, and the monitoring subsystem is used to control the gas extraction control valve so as to extract the first gas from the coal seam.

[0008] Optionally, the gas injection subsystem includes: a plurality of gas injection boreholes, a gas injection device, and a plurality of gas injection control valves; the plurality of gas injection boreholes are respectively arranged in the coal seam, and the outlet ends of the gas injection device are respectively connected to the inlet ends of the plurality of gas injection boreholes, the plurality of gas injection control valves are respectively arranged between the outlet ends of the gas injection device and the inlet ends of the plurality of gas injection boreholes; the communication end of the monitoring subsystem is respectively connected to the communication end of the gas injection device and the communication end of the gas injection control valve, and the monitoring subsystem is used to control the gas injection device and the gas injection control valve so that the gas injection device injects the second gas into the coal seam.

[0009] Optionally, the monitoring subsystem includes: a first monitoring module, a plurality of monitoring ends of the first monitoring module are respectively arranged at a plurality of gas extraction ends of the gas extraction subsystem, and the first monitoring module is used to monitor the total flow rate of the first gas and the methane concentration in the first gas; a control module, the communication end of the control module is connected to the communication end of the first monitoring module, and the control module is used to control the gas extraction subsystem and the gas injection subsystem according to the total flow rate of the first gas and the methane concentration in the first gas.

[0010] Optionally, the monitoring subsystem further includes: a second monitoring module, a plurality of monitoring ends of the second monitoring module are respectively arranged at a plurality of gas injection ends of the gas injection subsystem, and the second monitoring module is used to monitor the pressure of the second gas; wherein, the communication end of the control module is connected to the communication end of the second monitoring module, and the control module is used to control the gas injection subsystem according to the pressure of the second gas.

[0011] Optionally, the monitoring subsystem further includes: a third monitoring module disposed in the working space of the coal seam gas injection displacement and extraction, and the third monitoring module is used to monitor the oxygen concentration in the working space. The communication end of the control module is connected to the communication end of the third monitoring module, and the control module is used to control the gas injection subsystem according to the oxygen concentration in the working space; and / or, a fourth monitoring module disposed in the working space, and the fourth monitoring module is used to monitor the methane concentration in the working space. The communication end of the control module is connected to the communication end of the fourth monitoring module, and the control module is used to control the gas injection subsystem according to the methane concentration in the working space; and / or, a fifth monitoring module disposed in the working space, and the fifth monitoring module is used to monitor the temperature in the working space. The communication end of the control module is connected to the communication end of the fifth monitoring module, and the control module is used to control the gas injection subsystem according to the temperature in the working space; and / or, a video monitoring module disposed in the working space, and the video monitoring module is used to capture the image in the working space. The communication end of the control module is connected to the communication end of the video monitoring module, and the control module is used to monitor the extraction subsystem and the gas injection subsystem according to the image in the working space.

[0012] The second aspect of the present disclosure provides a method for regulating and controlling coal seam gas injection displacement and extraction, including: extracting a first gas from the coal seam and collecting the first pure gas extraction flow rate of the gas in the first gas; obtaining a first attenuation coefficient of the pure gas extraction flow rate according to the time change curve of the first pure gas extraction flow rate; obtaining a limit pure gas extraction flow rate according to the time change curve of the first pure gas extraction flow rate and the first attenuation coefficient; injecting a second gas into the coal seam, extracting the first gas from the coal seam, and collecting the second pure gas extraction flow rate of the gas in the first gas; obtaining a second attenuation coefficient of the pure gas extraction flow rate according to the time change curve of the second pure gas extraction flow rate; when the second pure gas extraction flow rate is not greater than the limit pure gas extraction flow rate, or the second attenuation coefficient is not less than the first attenuation coefficient, adjusting the pressure of the second gas according to a preset step pressure until the second pure gas extraction flow rate is not greater than the limit pure gas extraction flow rate and the second attenuation coefficient is not less than the first attenuation coefficient.

[0013] Optionally, the method further includes: extracting a first gas from the coal seam, and collecting a first total flow rate of the first gas and a first methane concentration in the first gas; obtaining a first pure gas extraction flow rate according to the first total flow rate and the first methane concentration; and / or, injecting a second gas into the coal seam, extracting the first gas from the coal seam, and collecting a second total flow rate of the first gas and a second methane concentration in the first gas; obtaining a second pure gas extraction flow rate according to the second total flow rate and the second methane concentration.

[0014] Optionally, the method further includes: collecting the first pure gas extraction flow rate every day, and obtaining the first decay coefficient according to the first pure gas extraction flow rate on the first day, the first pure gas extraction flow rate on the i-th day, and a curve fitting formula; and / or, collecting the second pure gas extraction flow rate every day, and obtaining the second decay coefficient according to the second pure gas extraction flow rate on the first day, the second pure gas extraction flow rate on the i-th day, and a curve fitting formula; wherein, the curve fitting formula is: q t = q1e -Nt , where q1 is the first pure gas extraction flow rate on the first day, q t is the first pure gas extraction flow rate on the i-th day, N is the decay coefficient, and t is the gas extraction time.

[0015] Optionally, the method further includes: collecting an oxygen concentration in the operation space for promoting gas extraction by gas injection into the coal seam, and stopping injecting the second gas into the coal seam when the oxygen concentration is lower than a preset oxygen concentration threshold; and / or, collecting a methane concentration in the operation space, and stopping injecting the second gas into the coal seam when the methane concentration is higher than a preset methane concentration threshold; and / or, collecting a temperature in the operation space, and stopping injecting the second gas into the coal seam when the temperature is higher than a preset temperature threshold.

[0016] The technical solution provided by the present disclosure may include the following beneficial effects:

[0017] Since multiple air extraction ends of the air extraction subsystem are respectively arranged in the coal seam, and the communication end of the monitoring subsystem is connected to the communication end of the air extraction subsystem, the monitoring subsystem can control the air extraction subsystem, so as to realize extracting the first gas from the coal seam. Moreover, since multiple gas injection ends of the gas injection subsystem are respectively arranged in the coal seam, and the communication end of the monitoring subsystem is connected to the communication end of the gas injection subsystem, the monitoring subsystem can control the gas injection subsystem, so as to realize injecting the second gas into the coal seam. Meanwhile, the monitoring subsystem also adjusts the pressure of the second gas according to a preset stepped pressure until the pure gas extraction flow rate of the gas in the first gas is within the flow rate range and the attenuation coefficient is within the coefficient range. Thus, through the air extraction subsystem, the gas injection subsystem and the monitoring subsystem, the effect monitoring and dynamic regulation of gas injection displacement and promotion of gas extraction in the coal seam are realized, thereby improving the gas extraction efficiency of gas injection displacement and promotion, and ensuring the real-time safety and high efficiency of the gas injection displacement technology.

[0018] Additional aspects and advantages of the present disclosure will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The above and / or additional aspects and advantages of the present disclosure will become apparent and be readily understood from the following description of embodiments in conjunction with the drawings, wherein:

[0020] Figure 1 is a schematic structural diagram of a monitoring system for gas injection displacement and promotion of coal seam gas according to an embodiment of the present disclosure;

[0021] Figure 2 is a schematic flowchart of a regulation method for gas injection displacement and promotion of coal seam gas according to an embodiment of the present disclosure;

[0022] Figure 3 is a time-varying curve graph according to an embodiment of the present disclosure;

[0023] As shown in the figure: 1. Air extraction subsystem, 11. Air extraction borehole, 12. Confluence pipe, 13. Air extraction branch pipe, 14. Air extraction control valve;

[0024] 2. Gas injection subsystem, 21. Gas injection borehole, 22. Gas injection equipment, 23. Gas injection control valve;

[0025] 3. Monitoring subsystem, 31. Control module, 32. First monitoring module, 33. Second monitoring module, 34. Third monitoring module, 35. Fourth monitoring module, 36. Fifth monitoring module, 37. Video monitoring module. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0026] Embodiments of the present disclosure will be described in detail below. Examples of the embodiments are shown in the accompanying drawings, where like or similar reference numerals denote like or similar elements or elements having like or similar functions throughout. The embodiments described below by referring to the drawings are exemplary only for explaining the present disclosure and should not be construed as limiting the present disclosure. On the contrary, the embodiments of the present disclosure include all variations, modifications, and equivalents falling within the spirit and scope of the appended claims.

[0027] As Figure 1 shown, an embodiment of the present disclosure provides a monitoring system for promoting gas extraction by injecting gas into coal seams, including: a gas extraction subsystem 1, a gas injection subsystem 2, and a monitoring subsystem 3. A plurality of gas extraction ends of the gas extraction subsystem 1 are respectively arranged in the coal seam, and the gas extraction subsystem 1 is used to extract a first gas from the coal seam. A plurality of gas injection ends of the gas injection subsystem 2 are respectively arranged in the coal seam, and the gas injection subsystem 2 is used to inject a second gas into the coal seam. Communication ends of the monitoring subsystem 3 are respectively connected to the communication ends of the gas extraction subsystem 1 and the gas injection subsystem 2. The monitoring subsystem 3 is used to adjust the pressure of the second gas according to a preset stepped pressure until the pure gas extraction flow rate of the gas in the first gas is within a flow rate range and the attenuation coefficient is within a coefficient range.

[0028] It can be understood that since a plurality of gas extraction ends of the gas extraction subsystem 1 are respectively arranged in the coal seam, and the communication end of the monitoring subsystem 3 is connected to the communication end of the gas extraction subsystem 1, the monitoring subsystem 3 can control the gas extraction subsystem 1, thereby realizing the extraction of the first gas from the coal seam. Moreover, since a plurality of gas injection ends of the gas injection subsystem 2 are respectively arranged in the coal seam, and the communication end of the monitoring subsystem 3 is connected to the communication end of the gas injection subsystem 2, the monitoring subsystem 3 can control the gas injection subsystem 2, thereby realizing the injection of the second gas into the coal seam. At the same time, the monitoring subsystem 3 also adjusts the pressure of the second gas according to a preset stepped pressure until the pure gas extraction flow rate of the gas in the first gas is within a flow rate range and the attenuation coefficient is within a coefficient range.

[0029] Thus, through the gas extraction subsystem 1, the gas injection subsystem 2, and the monitoring subsystem 3, the effect monitoring and dynamic adjustment of promoting gas extraction by injecting gas into coal seams are realized, thereby improving the gas extraction efficiency of promoting gas extraction by injecting gas, and ensuring the real-time safety and high efficiency of the gas injection displacement technology.

[0030] It should be noted that the gas extraction subsystem 1 is used to extract a first gas from the coal seam, the gas injection subsystem 2 is used to inject a second gas into the coal seam. The gas extraction subsystem 1 and the gas injection subsystem 2 cooperate to realize the gas extraction of promoting gas extraction by injecting gas. The monitoring subsystem 3 is used for parameter monitoring and regulation during the process of promoting gas extraction by injecting gas into coal seams, which can effectively solve problems such as poor adaptability of gas injection parameters to coal seam occurrence, lag in monitoring the gas extraction effect of promoting gas extraction by injecting gas, and rigid gas injection - gas extraction dynamic collaborative regulation mode, maximize the gas displacement and promotion of gas extraction, and ensure the safety of coal mining operations.

[0031] Among them, the specific types of the gas extraction subsystem 1, the gas injection subsystem 2, and the monitoring subsystem 3 can be set according to actual needs, and there is no limitation on this.

[0032] Such as Figure 1 As shown, in some embodiments, the gas extraction subsystem 1 includes: a plurality of gas extraction boreholes 11, a plurality of confluence pipes 12, a gas extraction branch pipe 13, and a plurality of gas extraction control valves 14. The plurality of gas extraction boreholes 11 are respectively arranged in the coal seam, and the intake ends of the confluence pipes 12 are respectively connected to the outlet ends of the plurality of gas extraction boreholes 11. The intake end of the gas extraction branch pipe 13 is connected to the outlet ends of the plurality of confluence pipes 12. The plurality of gas extraction control valves 14 are respectively arranged between the intake end of the gas extraction branch pipe 13 and the outlet ends of the plurality of confluence pipes 12. The communication end of the monitoring subsystem 3 is connected to the communication end of the gas extraction control valve 14, and the monitoring subsystem 3 is used to control the gas extraction control valve 14 so as to extract the first gas from the coal seam.

[0033] It can be understood that since the plurality of gas extraction boreholes 11 are respectively arranged in the coal seam, and the intake ends of the confluence pipes 12 are respectively connected to the outlet ends of the plurality of gas extraction boreholes 11, and the intake end of the gas extraction branch pipe 13 is connected to the outlet ends of the plurality of confluence pipes 12, the gas extraction branch pipe 13 can extract the first gas in the coal seam by using the plurality of confluence pipes 12 and the plurality of gas extraction boreholes 11. Moreover, since the plurality of gas extraction control valves 14 are respectively arranged between the intake end of the gas extraction branch pipe 13 and the outlet ends of the plurality of confluence pipes 12, the gas extraction control valve 14 can selectively conduct or cut off the passage between the intake end of the gas extraction branch pipe 13 and the outlet end of the confluence pipe 12.

[0034] At the same time, since the communication end of the monitoring subsystem 3 is connected to the communication end of the gas extraction control valve 14, the monitoring subsystem 3 can control the gas extraction control valve 14, thereby accurately realizing the gas extraction operation of injecting gas to displace and promote gas extraction.

[0035] It should be noted that the gas extraction boreholes 11 are used to be arranged in the coal seam to extract the first gas in the coal seam by using negative pressure. The specific type of the gas extraction boreholes 11 can be set according to actual needs, and there is no limitation on this.

[0036] The confluence pipes 12 are used to confluence the first gas in the plurality of gas extraction boreholes 11. The specific type of the confluence pipes 12 can be set according to actual needs, and there is no limitation on this. Among them, each confluence pipe 12 corresponds to a plurality of gas extraction boreholes 11. For example: each return pipe is connected to four gas extraction boreholes 11.

[0037] The gas extraction branch pipe 13 is used to transmit the negative pressure required for gas extraction. The specific type of the gas extraction branch pipe 13 can be set according to actual needs, and there is no limitation on this.

[0038] The air extraction control valve 14 is used to control the on-off of the passage between the intake end of the extraction branch pipe 13 and the outlet end of the confluence pipe 12. The specific type of the air extraction control valve 14 can be set according to actual needs, and there is no limitation on this. Among them, each air extraction control valve 14 corresponds to a confluence pipe 12, that is to say, the air extraction passage of each confluence pipe 12 can be independently controlled.

[0039] As Figure 1 shown, in some embodiments, the gas injection subsystem 2 includes: a plurality of gas injection boreholes 21, a gas injection device 22, and a plurality of gas injection control valves 23. The plurality of gas injection boreholes 21 are respectively arranged in the coal seam, and the outlet ends of the gas injection device 22 are respectively connected to the intake ends of the plurality of gas injection boreholes 21. The plurality of gas injection control valves 23 are respectively arranged between the outlet end of the gas injection device 22 and the intake ends of the plurality of gas injection boreholes 21. The communication ends of the monitoring subsystem 3 are respectively connected to the communication ends of the gas injection device 22 and the gas injection control valves 23, and the monitoring subsystem 3 is used to control the gas injection device 22 and the gas injection control valves 23 so that the gas injection device 22 injects a second gas into the coal seam.

[0040] It can be understood that since the plurality of gas injection boreholes 21 are respectively arranged in the coal seam, and the outlet ends of the gas injection device 22 are respectively connected to the intake ends of the plurality of gas injection boreholes 21, the gas injection device 22 can use the plurality of gas injection boreholes 21 to inject the second gas into the coal seam. And since the plurality of gas injection control valves 23 are respectively arranged between the outlet end of the gas injection device 22 and the intake ends of the plurality of gas injection boreholes 21, the gas injection control valves 23 can selectively conduct or cut off the passage between the intake end of the extraction branch pipe 13 and the outlet end of the confluence pipe 12.

[0041] At the same time, since the communication ends of the monitoring subsystem 3 are respectively connected to the communication ends of the gas injection device 22 and the gas injection control valves 23, the monitoring subsystem 3 can control the gas injection device 22 and the gas injection control valves 23, so as to accurately realize the gas injection displacement and enhanced coalbed methane extraction operation.

[0042] It should be noted that the gas injection boreholes 21 are used to be arranged in the coal seam to transport the second gas into the coal seam by positive pressure. The specific type of the gas injection boreholes 21 can be set according to actual needs, and there is no limitation on this.

[0043] The gas injection device 22 is used to generate positive pressure to transport the second gas into the coal seam by positive pressure. The specific type of the gas injection device 22 can be set according to actual needs, and there is no limitation on this.

[0044] The gas injection control valve 23 is used to control the on-off of the passage between the intake end of the extraction branch pipe 13 and the outlet end of the confluence pipe 12. The specific type of the gas injection control valve 23 can be set according to actual needs, and there is no limitation on this. Among them, each gas injection control valve 23 corresponds to a gas injection borehole 21, that is to say, the gas injection passage of each gas injection borehole 21 can be independently controlled.

[0045] As Figure 1 shown, in some embodiments, the monitoring subsystem 3 includes: a first monitoring module 32 and a control module 31. A plurality of monitoring ends of the first monitoring module 32 are respectively arranged at a plurality of gas extraction ends of the gas extraction subsystem 1, and the first monitoring module 32 is used to monitor the total flow rate of the first gas and the methane concentration in the first gas. The communication end of the control module 31 is connected to the communication end of the first monitoring module 32, and the control module 31 is used to control the gas extraction subsystem 1 and the gas injection subsystem 2 according to the total flow rate of the first gas and the methane concentration in the first gas.

[0046] It can be understood that since a plurality of monitoring ends of the first monitoring module 32 are respectively arranged at a plurality of gas extraction ends of the gas extraction subsystem 1, and the communication end of the control module 31 is connected to the communication end of the first monitoring module 32, the first monitoring module 32 can monitor the total flow rate of the first gas and the methane concentration in the first gas, so that the control module 31 can control the gas extraction subsystem 1 and the gas injection subsystem 2 according to the total flow rate of the first gas and the methane concentration in the first gas, and further realize the precise monitoring of the gas extraction operation of gas injection displacement and promotion.

[0047] It should be noted that the first monitoring module 32 is used to monitor the total flow rate of the first gas and the methane concentration in the first gas. The specific type of the first monitoring module 32 can be set according to actual needs, and there is no limitation on this. By way of example, the first monitoring module 32 can be a multi-parameter measuring instrument for gas extraction, which can not only monitor the total flow rate of the first gas and the methane concentration in the first gas, but also monitor parameters such as the negative pressure and carbon monoxide concentration in the first gas.

[0048] The control module 31 is used for the monitoring of the gas extraction subsystem 1 and the gas injection subsystem 2. The specific type of the control module 31 can be set according to actual needs, and there is no limitation on this. By way of example, the control module 31 includes: a substation system, a ring network system and a ground data center. The substation system is arranged in the working space, and the ground data center is arranged on the ground. The substation system is used for the monitoring of the gas extraction subsystem 1 and the gas injection subsystem 2. The substation system communicates with the ground data center through the ring network system to realize data upload and ground control.

[0049] As Figure 1As shown, in some embodiments, the monitoring subsystem 3 further includes: a second monitoring module 33. A plurality of monitoring ends of the second monitoring module 33 are respectively arranged at a plurality of gas injection ends of the gas injection subsystem 2, and the second monitoring module 33 is used to monitor the pressure of the second gas. Wherein, the communication end of the control module 31 is connected to the communication end of the second monitoring module 33, and the control module 31 is used to control the gas injection subsystem 2 according to the pressure of the second gas.

[0050] It can be understood that since a plurality of monitoring ends of the second monitoring module 33 are respectively arranged at a plurality of gas injection ends of the gas injection subsystem 2, and the communication end of the control module 31 is connected to the communication end of the second monitoring module 33, the second monitoring module 33 can monitor the pressure of the second gas, so that the control module 31 can control the gas injection subsystem 2 according to the pressure of the second gas, thereby realizing precise monitoring of the gas injection displacement and promoting gas extraction operation.

[0051] It should be noted that the second monitoring module 33 is used to monitor the pressure of the second gas. The specific type of the second monitoring module 33 can be set according to actual needs, and there is no limitation in this regard. By way of example, the second monitoring module 33 can be a gas injection parameter meter, which can not only monitor the pressure of the second gas, but also monitor parameters such as the flow rate of the second gas.

[0052] As Figure 1 shown, in some embodiments, the monitoring subsystem 3 further includes: a third monitoring module 34. The third monitoring module 34 is arranged in the working space of the coal seam gas injection displacement and promotion, and the third monitoring module 34 is used to monitor the oxygen concentration in the working space. The communication end of the control module 31 is connected to the communication end of the third monitoring module 34, and the control module 31 is used to control the gas injection subsystem 2 according to the oxygen concentration in the working space.

[0053] As Figure 1 shown, in some embodiments, the monitoring subsystem 3 further includes: a fourth monitoring module 35. The fourth monitoring module 35 is arranged in the working space, and the fourth monitoring module 35 is used to monitor the methane concentration in the working space. The communication end of the control module 31 is connected to the communication end of the fourth monitoring module 35, and the control module 31 is used to control the gas injection subsystem 2 according to the methane concentration in the working space;

[0054] As Figure 1 shown, in some embodiments, the monitoring subsystem 3 further includes: a fifth monitoring module 36. The fifth monitoring module 36 is arranged in the working space, and the fifth monitoring module 36 is used to monitor the temperature in the working space. The communication end of the control module 31 is connected to the communication end of the fifth monitoring module 36, and the control module 31 is used to control the gas injection subsystem 2 according to the temperature in the working space;

[0055] As Figure 1As shown, in some embodiments, the monitoring subsystem 3 further includes: a video monitoring module 37. The video monitoring module 37 is disposed in the operation space, and the video monitoring module 37 is used to capture the images in the operation space. The communication end of the control module 31 is connected to the communication end of the video monitoring module 37. The control module 31 is used to monitor the extraction subsystem 1 and the gas injection subsystem 2 according to the images in the operation space.

[0056] It can be understood that since the third monitoring module 34 is disposed in the operation space of coal seam gas injection displacement and promotion of extraction, and the communication end of the control module 31 is connected to the communication end of the third monitoring module 34, the third monitoring module 34 can monitor the oxygen concentration in the operation space, so that the control module 31 can control the gas injection subsystem 2 according to the oxygen concentration in the operation space.

[0057] Since the fourth monitoring module 35 is disposed in the operation space, and the communication end of the control module 31 is connected to the communication end of the fourth monitoring module 35, the fourth monitoring module 35 can monitor the methane concentration in the operation space, so that the control module 31 can control the gas injection subsystem 2 according to the methane concentration in the operation space.

[0058] Since the fifth monitoring module 36 is disposed in the operation space, and the communication end of the control module 31 is connected to the communication end of the fifth monitoring module 36, the fifth monitoring module 36 can monitor the temperature in the operation space, so that the control module 31 can control the gas injection subsystem 2 according to the temperature in the operation space.

[0059] Since the video monitoring module 37 is disposed in the operation space, and the communication end of the control module 31 is connected to the communication end of the video monitoring module 37, the video monitoring module 37 can capture the images in the operation space, so that the control module 31 can monitor the extraction subsystem 1 and the gas injection subsystem 2 according to the images in the operation space.

[0060] Thus, through the cooperation of the third monitoring module 34, the fourth monitoring module 35, the fifth monitoring module 36 and the video monitoring module 37, the precise monitoring of the gas extraction operation of gas injection displacement and promotion is realized.

[0061] It should be noted that the third monitoring module 34 is used to monitor the oxygen concentration in the operation space. The specific type of the third monitoring module 34 can be set according to actual needs, and there is no limitation thereto. By way of example, the third monitoring module 34 can be an oxygen sensor.

[0062] The fourth monitoring module 35 is used to monitor the methane concentration in the operation space. The specific type of the fourth monitoring module 35 can be set according to actual needs, and there is no limitation thereto. By way of example, the fourth monitoring module 35 can be a methane sensor.

[0063] The fifth monitoring module 36 is used to monitor the temperature in the working space. The specific type of the fifth monitoring module 36 can be set according to actual needs, and there is no limitation in this regard. By way of example, the fifth monitoring module 36 can be a temperature sensor.

[0064] The video monitoring module 37 is used to capture the images in the working space to provide a basis for the remote unattended operation of the system. The specific type of the video monitoring module 37 can be set according to actual needs, and there is no limitation in this regard. By way of example, the video monitoring module 37 can be a video monitor.

[0065] As Figure 2 shown, an embodiment of the present disclosure also provides a method for regulating coal seam gas injection displacement and extraction promotion, including:

[0066] S1: Extract the first gas from the coal seam and collect the first pure gas extraction flow rate of the gas in the first gas.

[0067] S2: Obtain the first attenuation coefficient of the pure gas extraction flow rate according to the time change curve of the first pure gas extraction flow rate of the gas.

[0068] S3: Obtain the limit pure gas extraction flow rate according to the time change curve of the first pure gas extraction flow rate of the gas and the first attenuation coefficient.

[0069] S4: Inject the second gas into the coal seam, extract the first gas from the coal seam, and collect the second pure gas extraction flow rate of the gas in the first gas.

[0070] S5: Obtain the second attenuation coefficient of the pure gas extraction flow rate according to the time change curve of the second pure gas extraction flow rate of the gas.

[0071] S6: When the second pure gas extraction flow rate is not greater than the limit pure gas extraction flow rate, or the second attenuation coefficient is not less than the first attenuation coefficient, adjust the pressure of the second gas according to the preset stepped pressure until the second pure gas extraction flow rate is not greater than the limit pure gas extraction flow rate, and the second attenuation coefficient is not less than the first attenuation coefficient.

[0072] It can be understood that the first gas is extracted from the coal seam, and the first attenuation coefficient and the ultimate pure gas drainage flow rate are sequentially obtained according to the collected pure gas drainage flow rate of the first gas drainage, so as to obtain the reference threshold value in the gas injection displacement promotion drainage mode under the conventional drainage mode. Moreover, the second gas is injected into the coal seam, the first gas is extracted from the coal seam, and the pure gas drainage flow rate of the second gas in the first gas is collected, and the second attenuation coefficient of the pure gas drainage flow rate is obtained according to the collected pure gas drainage flow rate of the second gas. Thus, when the pure gas drainage flow rate of the second gas is not greater than the ultimate pure gas drainage flow rate, or the second attenuation coefficient is not less than the first attenuation coefficient, the pressure of the second gas is adjusted according to the preset stepped pressure until the pure gas drainage flow rate of the second gas is not greater than the ultimate pure gas drainage flow rate and the second attenuation coefficient is not less than the first attenuation coefficient, so as to realize the real-time monitoring of the gas drainage effect and the dynamic adjustment of the gas drainage, and better ensure the real-time safety and efficiency of the gas injection displacement technology.

[0073] It should be noted that the time variation curve can be formed by the pure gas drainage flow rate data of one month, as Figure 3 shown.

[0074] The preset stepped pressure can be 0.5 MPa. That is to say, when the pure gas drainage flow rate of the second gas is not greater than the ultimate pure gas drainage flow rate, or the second attenuation coefficient is not less than the first attenuation coefficient, the injection pressure of 0.5 MPa is continuously adjusted until the pure gas drainage flow rate of the second gas is not greater than the ultimate pure gas drainage flow rate and the second attenuation coefficient is not less than the first attenuation coefficient.

[0075] When the pure gas drainage flow rate of the second gas is not greater than the ultimate pure gas drainage flow rate, or the second attenuation coefficient is not less than the first attenuation coefficient, the gas injection displacement promotion drainage is completed, and the ground data issues an instruction to close the gas injection subsystem, and the injection-drawing ratio is automatically analyzed based on the data monitored by the gas injection parameter meter and the data monitored by the gas drainage multi-parameter detector.

[0076] In some embodiments, the method further includes: extracting the first gas from the coal seam, and collecting the first total flow rate of the first gas and the first methane concentration in the first gas; obtaining the first pure gas drainage flow rate according to the first total flow rate and the first methane concentration.

[0077] It can be understood that by using the first total flow rate of the first gas and the first methane concentration in the first gas, the first pure gas drainage flow rate can be obtained, and thus the first attenuation coefficient and the ultimate pure gas drainage flow rate can be obtained according to the first pure gas drainage flow rate.

[0078] In some embodiments, the method further includes: injecting the second gas into the coal seam, extracting the first gas from the coal seam, and collecting the second total flow rate of the first gas and the second methane concentration in the first gas; obtaining the second pure gas drainage flow rate according to the second total flow rate and the second methane concentration.

[0079] It can be understood that, by using the second total flow rate of the first gas and the second methane concentration in the first gas, the second pure gas drainage flow rate can be obtained. Then, based on the second pure gas drainage flow rate, the second attenuation coefficient can be obtained. Furthermore, by comparing the second pure gas drainage flow rate with the limit pure gas drainage flow rate and comparing the second attenuation coefficient with the first attenuation coefficient, the real-time monitoring of the gas drainage effect and the dynamic adjustment of gas drainage can be realized.

[0080] It should be noted that the pure gas drainage flow rate obtained from the total flow rate and methane concentration can be expressed by the formula:

[0081] q 纯 =Q 混 ×C.

[0082] Wherein, q 纯 is the pure gas drainage flow rate of the first gas, with the unit of m 3 / min, Q 混 is the total flow rate of the first gas, with the unit of m 3 / min, and C is the methane concentration in the first gas, with the unit of %.

[0083] In some embodiments, the method further includes: collecting the first pure gas drainage flow rate every day, and obtaining the first attenuation coefficient according to the first pure gas drainage flow rate on the first day, the first pure gas drainage flow rate on the i-th day, and the curve fitting formula.

[0084] In some embodiments, the method further includes: collecting the second pure gas drainage flow rate every day, and obtaining the second attenuation coefficient according to the second pure gas drainage flow rate on the first day, the second pure gas drainage flow rate on the i-th day, and the curve fitting formula.

[0085] Wherein, the curve fitting formula is: q t =q1e -Nt , q1 is the pure gas drainage flow rate on the first day, q t is the pure gas drainage flow rate on the i-th day, N is the attenuation coefficient, and t is the gas drainage time.

[0086] It should be noted that the gas drainage time refers to the time point when the pure gas drainage flow rate is collected on the i-th day, which can be in days, such as i, or more specific hours, minutes, etc.

[0087] In some embodiments, the method further includes: collecting the oxygen concentration in the operation space of coal seam gas injection displacement and extraction, and when the oxygen concentration is lower than the preset oxygen concentration threshold, stopping injecting the second gas into the coal seam.

[0088] It can be understood that when the oxygen concentration is lower than the preset oxygen concentration threshold, stopping injecting the second gas into the coal seam can avoid too low oxygen concentration and thus ensure safe operation underground.

[0089] In some embodiments, the method further includes: collecting the methane concentration in the working space, and when the methane concentration is higher than a preset methane concentration threshold, stopping injecting the second gas into the coal seam.

[0090] It can be understood that when the methane concentration is higher than the preset methane concentration threshold, stopping injecting the second gas into the coal seam can avoid too high methane concentration and thus ensure safe underground operation.

[0091] In some embodiments, the method further includes: collecting the temperature in the working space, and when the temperature is higher than a preset temperature threshold, stopping injecting the second gas into the coal seam.

[0092] It can be understood that when the temperature is higher than the preset temperature threshold, stopping injecting the second gas into the coal seam can avoid too high temperature and thus ensure safe underground operation.

[0093] It should be noted that according to the requirements of the "Coal Mine Safety Regulations", the oxygen concentration in the underground working environment shall not be lower than 20%, the methane concentration shall not be higher than 1%, and the temperature shall not be higher than 30°C. To ensure operation safety, it is considered to increase the early warning lower limit value. Among them, the alarm lower limit value of the oxygen sensor is 19%, the alarm lower limit of the methane sensor is 0.6%, and the alarm lower limit value of the temperature sensor is 28°C.

[0094] During the implementation of the gas injection displacement and enhanced drainage process, when an alarm occurs in environmental monitoring, the ground data center remotely controls the shutdown of the gas injection subsystem, and tracks and records the images of the area where the gas injection displacement and enhanced drainage process is implemented through the video monitoring module, providing a remote decision-making basis for ground operators.

[0095] The system and method of this embodiment, compared with the existing technical means of coal seam gas injection displacement and enhanced drainage, consider the real-time monitoring of gas extraction effect, environmental safety monitoring and dynamic adjustment of gas extraction, and can better ensure the real-time safety and efficiency of the gas injection displacement technology.

[0096] It should be noted that in the description of the present disclosure, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. In addition, in the description of the present disclosure, unless otherwise specified, the meaning of "a plurality" is two or more.

[0097] Any process or method description depicted in a flowchart or otherwise described herein can be understood to represent a module, segment, or portion of code that includes one or more executable instructions for implementing a specific logical function or process. The scope of the preferred embodiments of the present disclosure includes additional implementations in which functions may be executed in a substantially simultaneous manner or in an order opposite to that shown or discussed, according to the functions involved, which should be understood by those skilled in the art to which the embodiments of the present disclosure pertain.

[0098] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present disclosure. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0099] Although the embodiments of the present disclosure have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present disclosure. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present disclosure.

Claims

1. A monitoring system for promoting the extraction of coal seam gas by gas injection displacement, characterized in that, Including: A gas extraction subsystem, with multiple gas extraction ends of the gas extraction subsystem respectively arranged in the coal seam, and the gas extraction subsystem is used to extract a first gas from the coal seam; An air injection subsystem, with multiple air injection ends of the air injection subsystem respectively arranged in the coal seam, and the air injection subsystem is used to inject a second gas into the coal seam; A monitoring subsystem, with the communication ends of the monitoring subsystem respectively connected to the communication ends of the gas extraction subsystem and the air injection subsystem. The monitoring subsystem is used to adjust the pressure of the second gas according to a preset cascade pressure until the pure gas extraction flow rate of the gas in the first gas is within the flow range and the attenuation coefficient is within the coefficient range.

2. The coal seam gas injection displacement and promotion pumping monitoring system according to claim 1, wherein The gas extraction subsystem includes: Multiple gas extraction boreholes, multiple manifold pipes, a gas extraction branch pipe, and multiple gas extraction control valves; Multiple of the gas extraction boreholes are respectively arranged in the coal seam, and the inlet ends of the manifold pipes are respectively connected to the outlet ends of the multiple gas extraction boreholes. The inlet end of the gas extraction branch pipe is connected to the outlet ends of the multiple manifold pipes. Multiple gas extraction control valves are respectively arranged between the inlet end of the gas extraction branch pipe and the outlet ends of the multiple manifold pipes; The communication end of the monitoring subsystem is connected to the communication end of the gas extraction control valve, and the monitoring subsystem is used to control the gas extraction control valve so as to extract the first gas from the coal seam.

3. The coal seam gas injection displacement and promotion extraction monitoring system according to claim 1, characterized in that The air injection subsystem includes: Multiple air injection boreholes, air injection equipment, and multiple air injection control valves; Multiple of the air injection boreholes are respectively arranged in the coal seam, and the outlet ends of the air injection equipment are respectively connected to the inlet ends of the multiple air injection boreholes. Multiple air injection control valves are respectively arranged between the outlet ends of the air injection equipment and the inlet ends of the multiple air injection boreholes; The communication end of the monitoring subsystem is respectively connected to the communication ends of the air injection equipment and the air injection control valve, and the monitoring subsystem is used to control the air injection equipment and the air injection control valve so that the air injection equipment injects the second gas into the coal seam.

4. The coal seam gas injection displacement and promotion extraction monitoring system according to claim 1, wherein, The monitoring subsystem includes: A first monitoring module, with multiple monitoring ends of the first monitoring module respectively arranged at multiple gas extraction ends of the gas extraction subsystem, and the first monitoring module is used to monitor the total flow rate of the first gas and the methane concentration in the first gas; A control module, with the communication end of the control module connected to the communication end of the first monitoring module, and the control module is used to control the gas extraction subsystem and the air injection subsystem according to the total flow rate of the first gas and the methane concentration in the first gas.

5. The coal seam gas injection displacement and extraction promotion monitoring system according to claim 4, characterized in that The monitoring subsystem further includes: A second monitoring module, with multiple monitoring ends of the second monitoring module respectively arranged at multiple air injection ends of the air injection subsystem, and the second monitoring module is used to monitor the pressure of the second gas; Wherein, the communication end of the control module is connected to the communication end of the second monitoring module, and the control module is used to control the air injection subsystem according to the pressure of the second gas.

6. The coal seam gas injection displacement and promotion pumping monitoring system according to claim 4, characterized in that, The monitoring subsystem further includes: A third monitoring module, which is arranged in the operation space of the coal seam gas injection displacement and extraction, and the third monitoring module is used to monitor the oxygen concentration in the operation space. The communication end of the control module is connected to the communication end of the third monitoring module, and the control module is used to control the gas injection subsystem according to the oxygen concentration in the operation space; and / or, A fourth monitoring module, which is arranged in the operation space, and the fourth monitoring module is used to monitor the methane concentration in the operation space. The communication end of the control module is connected to the communication end of the fourth monitoring module, and the control module is used to control the gas injection subsystem according to the methane concentration in the operation space; and / or, A fifth monitoring module, which is arranged in the operation space, and the fifth monitoring module is used to monitor the temperature in the operation space. The communication end of the control module is connected to the communication end of the fifth monitoring module, and the control module is used to control the gas injection subsystem according to the temperature in the operation space; and / or, A video monitoring module, which is arranged in the operation space, and the video monitoring module is used to capture the picture in the operation space. The communication end of the control module is connected to the communication end of the video monitoring module, and the control module is used to monitor the extraction subsystem and the gas injection subsystem according to the picture in the operation space.

7. A method for regulating and controlling gas injection displacement and promoting gas extraction in coal seams, characterized in that, comprising: Extracting a first gas from the coal seam and collecting the first pure gas extraction flow rate of the first gas; Obtaining a first attenuation coefficient of the pure gas extraction flow rate according to the time change curve of the first pure gas extraction flow rate of the first gas; Obtaining the limit pure gas extraction flow rate according to the time change curve of the first pure gas extraction flow rate of the first gas and the first attenuation coefficient; Injecting a second gas into the coal seam, extracting the first gas from the coal seam, and collecting the second pure gas extraction flow rate of the first gas; Obtaining a second attenuation coefficient of the pure gas extraction flow rate according to the time change curve of the second pure gas extraction flow rate of the second gas; When the second pure gas extraction flow rate is not greater than the limit pure gas extraction flow rate, or the second attenuation coefficient is not less than the first attenuation coefficient, adjusting the pressure of the second gas according to a preset stepped pressure until the second pure gas extraction flow rate is not greater than the limit pure gas extraction flow rate and the second attenuation coefficient is not less than the first attenuation coefficient.

8. The coal seam gas injection displacement promotion and extraction regulation method according to claim 7, characterized in that, The method further includes: Extracting a first gas from the coal seam, collecting the first total flow rate of the first gas and the first methane concentration in the first gas; obtaining the first pure gas extraction flow rate according to the first total flow rate and the first methane concentration; and / or, Injecting a second gas into the coal seam, extracting the first gas from the coal seam, and collecting the second total flow rate of the first gas and the second methane concentration in the first gas; obtaining the second pure gas extraction flow rate according to the second total flow rate and the second methane concentration.

9. The coal seam gas injection displacement and extraction promotion and regulation method according to claim 7, characterized in that The method further includes: Collect the daily net gas drainage flow of the first type, and obtain the first attenuation coefficient according to the net gas drainage flow of the first type on the first day, the net gas drainage flow of the first type on the i-th day, and the curve fitting formula; and / or Collect the daily net gas drainage flow of the second type, and obtain the second attenuation coefficient according to the net gas drainage flow of the second type on the first day, the net gas drainage flow of the second type on the i-th day, and the curve fitting formula; Among them, the curve fitting formula is: q t = q1e -Nt , where q1 is the pure gas drainage flow on the first day, q t is the pure gas drainage flow on the i-th day, N is the attenuation coefficient, and t is the gas drainage time.

10. The coal seam gas injection displacement promotion and extraction regulation method according to claim 7, characterized in that, The method further includes: Collect the oxygen concentration in the operation space for promoting gas extraction by injecting gas into the coal seam, and stop injecting the second gas into the coal seam when the oxygen concentration is lower than the preset oxygen concentration threshold; and / or Collect the methane concentration in the operation space, and stop injecting the second gas into the coal seam when the methane concentration is higher than the preset methane concentration threshold; and / or Collect the temperature in the operation space, and stop injecting the second gas into the coal seam when the temperature is higher than the preset temperature threshold.

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