Comprehensive management and control system and method for curved directional long drill holes in target coal seam

Abstract

The invention discloses a comprehensive management and control system and method for curved directional long drill holes of a target coal seam, and the comprehensive management and control system comprises a negative pressure extraction module, a high-pressure nitrogen injection module, an intelligent regulation and control module and a multi-effect cooperation pipeline. The pit drainage operation of the inner extraction pipe is firstly carried out through the multi-effect collaborative pipeline, then the nitrogen injection displacement operation of the outer nitrogen injection pipe is carried out, and finally the gas extraction operation of the inner extraction pipe is carried out, so that the integrated comprehensive control of pit accumulated water drainage, nitrogen injection displacement and gas extraction of the same drill hole and the same pipeline is realized; while the nitrogen injection flow increasing and pumping promoting effects are improved, the engineering construction period is shortened, the resource allocation is optimized, and the construction cost is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of coal mine gas extraction, and in particular to a comprehensive management and control system and method for curved directional long drilling of a target coal seam. Background Art

[0002] As my country's coal resources gradually move towards the stage of deep mining, the "three highs and one low" characteristics of coal seams are becoming more and more obvious. Traditional drilling pre-extraction is difficult to overcome the problem of low permeability of coal seams. Its pre-extraction takes a long time and the borehole gas flow decays quickly, which cannot meet the needs of mining succession and safe production. With the continuous advancement of science and technology, gas injection gas displacement technology has made breakthrough progress from theory to on-site implementation. This technology increases the internal gas pressure of the coal body, accelerates the seepage rate of the mixed gas, injects strong power into the coal seam flow field and forms a reliable gas migration channel, effectively reduces the effective partial pressure of gas, and promotes the desorption of adsorbed gas, thereby solving the problem of insufficient pressure drop in coal seams in the later stage of mining. Therefore, gas injection gas displacement technology has become a key technical means to improve gas extraction efficiency and meet the challenges of deep coal seam mining.

[0003] However, for the regional nitrogen injection to promote extraction in coal seam directional long drilling, affected by sedimentation, structure, etc., in many cases, the coal seam is not uniformly and stably distributed along the strike. For the mineable coal seam, there are mainly the following situations: 1) The thickness of the coal seam is relatively stable, but the coal seam is affected by folds or fault structures and is wavy or undulating along the strike with the coal-bearing strata; 2) Affected by sedimentation or structure, the thickness of the coal seam changes in a wavy or undulating manner along the strike. 3) For the construction of long-distance drilling, the drill rod is too long, which will cause the borehole to deflect. Therefore, under the condition that the coal seam is wavy or undulating along the strike, the trajectory of the regional nitrogen injection directional long drilling arranged along the strike is bound to show wavy or undulating changes, which is the so-called curved nitrogen injection to promote extraction directional long drilling.

[0004] At present, there are the following problems in regional nitrogen injection to displace water accumulation in long directional curved borehole pits. First, it will affect the displacement effect. On the one hand, it will reduce the displacement efficiency. Water accumulation or slag clogging in the low-point pits of the borehole will affect the nitrogen injection displacement efficiency and even isolate the high-pressure nitrogen injection. The space occupied by nitrogen will reduce the contact area between nitrogen and gas in the coal seam, making it difficult for nitrogen to effectively displace methane from the coal seam. This will lead to reduced displacement efficiency and prolonged displacement time; on the other hand, it will also affect the nitrogen distribution. The presence of water accumulation will change the fluid distribution in the borehole, so that the seepage, diffusion and adsorption process of nitrogen in the coal seam will be disturbed. This may cause nitrogen to be unable to be evenly distributed throughout the coal seam, thereby affecting the displacement effect. In addition, it will also affect the characteristics of the coal seam. On the one hand, it will change the pore structure of the coal seam. Water accumulation in the borehole may have a certain impact on the pore structure of the coal seam, such as causing pore blockage or changing the pore size. This will affect the adsorption capacity of the coal seam for methane, and thus affect the displacement effect. On the other hand, it will affect the permeability of the coal seam. The presence of accumulated water will reduce the permeability of the coal seam, making it difficult for nitrogen to flow smoothly in the coal seam. This will increase the pressure loss during the nitrogen displacement process, thereby reducing the displacement efficiency. These problems will result in poor gas extraction results, and there will also be certain safety issues. If the accumulated water in the borehole is not handled properly, it may cause safety accidents, such as borehole wall collapse or other geological disasters. It may also cause corrosion or damage to the drilling equipment, increase the cost of repairing and replacing equipment, and deteriorate the working environment, increasing the difficulty and danger of the operation.

[0005] In summary, it is particularly important and urgent to solve the problem of water accumulation in depressions in directional long boreholes that are promoted by nitrogen injection in curved areas. However, the current technical methods for borehole drainage in the industry are mainly aimed at ordinary downward boreholes, including gas lift water method, orifice drainage method, deep well pump drainage method in the hole, etc. For the problem of water accumulation in curved long boreholes, the existing technology adopts the method of adding branch holes to solve this problem, but there are also some shortcomings. First, the construction of additional branch boreholes is limited by geological conditions, and its drilling efficiency and success rate will be affected to a certain extent; second, the construction of branch boreholes has certain difficulties in controlling the borehole trajectory, and the trajectory may deviate from the designed path, which will affect the drainage effect and the quality of subsequent projects; at the same time, the addition of branch boreholes may increase safety risks during construction, such as drill rod bending, borehole collapse, etc.; in addition, it also significantly increases construction costs. Summary of the invention

[0006] The embodiment of the present application provides a comprehensive management and control system and method for curved directional long drilling holes in the target coal seam, thereby realizing the integrated management and control of pit water discharge, nitrogen injection displacement and gas extraction in the same borehole and the same pipeline. It can improve the effect of nitrogen injection to increase flow and promote extraction, shorten the construction period, optimize resource allocation, and reduce construction costs.

[0007] In order to achieve the above object, the technical solution of the embodiment of the present invention is:

[0008] In the first aspect, an embodiment of the present invention provides a comprehensive management and control system for a curved directional long borehole of a target coal seam, including: a negative pressure extraction module, a high-pressure nitrogen injection module, an intelligent control module and a multi-effect coordinated pipeline; the multi-effect coordinated pipeline is arranged in the curved directional long borehole, including an inner extraction pipe of an inner layer and an outer nitrogen injection pipe of an outer layer; wherein the inner extraction pipe is used to extract the accumulated water in the borehole and perform gas extraction operations, and the external nitrogen injection pipe is used to inject nitrogen into the borehole; the negative pressure extraction module is used to generate a negative pressure environment, and realize the extraction of accumulated water and gas in the borehole through the inner extraction pipe; the high-pressure nitrogen injection module is used to provide high-pressure nitrogen, and inject nitrogen into the borehole through the external nitrogen injection pipe to realize the displacement effect of nitrogen and enhance the gas fluidity in the target coal seam; the intelligent The control module is respectively connected to the negative pressure extraction module, the high-pressure nitrogen injection module and the multi-effect collaborative pipeline, and is used for intelligently controlling the working states of the negative pressure extraction module and the high-pressure nitrogen injection module; wherein, the specific process of intelligent control includes: first, starting and controlling the operation of the negative pressure extraction module, extracting the accumulated water in the borehole through the internal extraction pipe, and closing the negative pressure extraction module after the accumulated water is extracted; then starting and controlling the operation of the high-pressure nitrogen injection module, performing nitrogen injection displacement operation through the external nitrogen injection pipe, and closing the high-pressure nitrogen injection module after the nitrogen injection displacement operation reaches the preset conditions; finally, starting and controlling the operation of the negative pressure extraction module again, extracting the gas in the borehole through the internal extraction pipe, thereby realizing the integrated management and control of the discharge of accumulated water in the curved directional long borehole pit, nitrogen injection displacement and gas extraction.

[0009] In some possible implementations, the internal extraction pipe and the external nitrogen injection pipe are connected via a separation connection device, and the number of the separation connection devices is determined according to the length of the curved directional long borehole; the main body of the separation connection device is a ventilation double sleeve, and a one-way valve is provided at each of the upper and lower ports, and filters are provided at the outer ends of the two one-way valves.

[0010] In some possible implementations, a high-pressure nitrogen injection stop valve and a negative pressure extraction stop valve are arranged between the multi-effect collaborative pipeline and the intelligent control module; the high-pressure nitrogen injection stop valve is used to control the flow and stop of the high-pressure nitrogen in the external nitrogen injection pipe, and the negative pressure extraction stop valve is used to control the flow and stop of the accumulated water or gas in the internal extraction pipe; when the negative pressure extraction module is working, the high-pressure nitrogen injection stop valve is closed and the negative pressure extraction stop valve is opened; when the high-pressure nitrogen injection module is working, the high-pressure nitrogen injection stop valve is opened and the negative pressure extraction stop valve is closed.

[0011] In some possible implementations, a sensor is provided at the end of the multi-effect collaborative pipeline for real-time monitoring of the pressure and concentration data in the borehole; the intelligent control module determines whether to perform nitrogen re-injection or re-drainage according to the monitored pressure and concentration data.

[0012] In some possible implementations, the curved directional long boreholes include multiple, each of which is arranged with a multi-effect collaborative pipeline; a connection regulator is provided between the multiple multi-effect collaborative pipelines and the intelligent control module, and the intelligent control module can control the connection regulator to realize the replacement of the connection with the end of each multi-effect collaborative pipeline.

[0013] In some possible implementations, the connection regulator is also used to indirectly achieve the effect of pulse nitrogen injection when performing nitrogen injection displacement operations.

[0014] In some possible implementations, the tube head of the inner extraction tube is in a closed state; and the density of the nitrogen injection ports provided on the outer nitrogen injection tube gradually increases from the outside to the inside of the borehole.

[0015] In some possible implementations, the sealing section of the curved directional long borehole is arranged between the elastic zone and the original stress zone of the stress concentration zone.

[0016] In the second aspect, an embodiment of the present invention provides a method for comprehensive control of curved directional long drilling holes in a target coal seam, which is applied to the comprehensive control system for curved directional long drilling holes in a target coal seam provided in the first aspect, including: designing a curved directional long drilling trajectory according to a preset nitrogen injection displacement flow increase and extraction promotion target, the occurrence conditions of the coal and rock formations at the target working face, and the performance of the directional drilling construction equipment; performing drilling construction according to the designed curved directional long drilling trajectory, and arranging a multi-effect collaborative pipeline in the long borehole after the drilling is completed; sealing the borehole between the elastic zone of the stress concentration zone and the original stress zone; closing the negative pressure extraction shut-off valve, opening the high-pressure nitrogen injection shut-off valve, and starting And control the operation of the negative pressure extraction module to discharge the accumulated water in the borehole through the internal extraction pipe; when it is determined that the pumping is completed according to the flow data of the internal extraction pipe, close the negative pressure extraction module, open the negative pressure extraction stop valve, close the high-pressure nitrogen injection stop valve, start and control the operation of the high-pressure nitrogen injection module, and perform nitrogen injection displacement operations through the external nitrogen injection pipe; after the nitrogen injection displacement operation reaches the preset conditions, close the high-pressure nitrogen injection module, close the negative pressure extraction stop valve, open the high-pressure nitrogen injection stop valve, start and control the operation of the negative pressure extraction module, and perform gas extraction operations through the internal extraction pipe, so as to realize the integrated management and control of the discharge of accumulated water in the curved directional long borehole pit, nitrogen injection displacement and gas extraction.

[0017] One or more technical solutions provided in the embodiments of the present invention have at least the following technical effects or advantages:

[0018] In the embodiment of the present invention, the multi-effect collaborative pipeline can be applied to most curved long boreholes, and can flexibly respond to various complex and changeable geological environments, ensuring that whether in a long winding borehole or in an environment facing extreme geological challenges, the efficient implementation of the nitrogen injection flow-increasing and pumping-promoting project can be achieved, thereby meeting the diversified needs of geological exploration and engineering implementation. In addition, the construction requirements of redundant branch boreholes in the drainage operation of the traditional curved directional long borehole are avoided, which not only reduces the potential damage to the geological structure, but also effectively improves the overall construction efficiency. By reducing unnecessary drilling operations, not only the natural state of underground resources is protected, but also the practice of environmentally friendly construction concepts is promoted. In addition, through the multi-effect collaborative pipeline, the pit drainage operation of the inner extraction pipe is first carried out, followed by the nitrogen injection displacement operation of the external nitrogen injection pipe, and finally the gas extraction operation of the inner extraction pipe is carried out, so as to realize the integrated management and control of the pit water discharge, nitrogen injection displacement and gas extraction of the same borehole and the same pipeline. The multi-effect implementation of drilling operations solves the problem of time waste caused by laying out the water pumping pipeline first and then the nitrogen injection pipeline in traditional operations, greatly shortening the overall construction period of the project; by efficiently integrating the construction steps, it not only greatly reduces the occupied time of construction equipment, but also effectively optimizes resource allocation, further reduces construction costs, and improves the economic benefits of the project. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention, the accompanying drawings required for use in the embodiments of the present invention will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying any creative work.

[0020] Figure 1 It is a schematic diagram of the long curved borehole and the water accumulation in the pit;

[0021] Figure 2 A schematic diagram of the structure of a comprehensive control system for curved directional long drilling of a target coal seam provided for the implementation of the present invention;

[0022] Figure 3 It is a schematic structural diagram of the main components of the separation and connection device in an embodiment of the present invention;

[0023] Figure 4 It is a structural schematic diagram of a separation and connection device in a multi-effect collaborative pipeline according to an embodiment of the present invention;

[0024] Figure 5 Schematic diagram of the structure of the sealing position in the drill hole in the embodiment of the present invention;

[0025] Figure 6 It is a structural schematic diagram of another integrated control system for curved directional long drilling of target coal seams in an embodiment of the present invention;

[0026] Figure 7 It is a schematic diagram of an embodiment of a method for comprehensive control of a curved directional long drilling hole in a target coal seam according to an embodiment of the present invention;

[0027] Figure 8 It is a structural schematic diagram of the multi-effect cooperative pipeline pumping process at the beginning of the embodiment of the present invention;

[0028] Fig. 9 It is a structural schematic diagram of the multi-effect cooperative pipeline pumping process in an embodiment of the present invention;

[0029] Fig.10 It is a structural schematic diagram of a multi-effect coordinated pipeline nitrogen injection displacement process in an embodiment of the present invention;

[0030] Fig.11 It is a structural schematic diagram of the multi-effect coordinated pipeline gas extraction process in an embodiment of the present invention. DETAILED DESCRIPTION

[0031] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0032] In the relevant description of this embodiment, the terms "including, containing, having" and the like are open terms and are generally understood to include but not be limited to; the term "at least one" is generally understood to mean one or more, where "plurality" refers to two or more; the term "at least one of the following" or similar expressions refers to any combination of these items, including any combination of single or plural items, for example, "at least one of a, b or c", or "at least one of a, b and c", can all represent: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, c can be single or multiple, respectively; the symbol "A / B" is used to describe the selection relationship of associated objects, generally indicating an "or" relationship before and after.

[0033] In the following description of the present embodiment, the terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application. The singular forms "a" and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.

[0034] Those skilled in the art should understand that in the following description of the embodiments of the present application, the order of serial numbers does not mean the order of execution, some or all of the steps can be executed in parallel or sequentially, and the execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0035] Those skilled in the art will appreciate that the numerical ranges in the embodiments of the present application are to be construed as also specifically disclosing each intermediate value between the upper and lower limits of the scope. Each smaller range between the intermediate value in any stated value or stated range and any other stated value or intermediate value in the range is also included in the present invention. The upper and lower limits of these smaller ranges may be independently included or excluded in the scope.

[0036] Unless otherwise specified, the technical / scientific terms used herein have the same meanings as those generally understood by those skilled in the art to which this application belongs. Although this application only describes preferred methods and materials, any methods and materials similar or equivalent to these may also be used in the implementation or testing of this application. All documents mentioned in this specification are incorporated by reference to disclose and describe methods and / or materials related to the documents. In the event of a conflict with any incorporated document, the content of this specification shall prevail.

[0037] In order to illustrate the technical solution of the present invention, specific embodiments are provided below for illustration.

[0038] As my country's coal resources gradually move towards the stage of deep mining, the "three highs and one low" characteristics of coal seams are becoming more and more obvious. Traditional drilling pre-extraction is difficult to overcome the problem of low permeability of coal seams. Its pre-extraction takes a long time and the borehole gas flow decays quickly, which cannot meet the needs of mining succession and safe production. With the continuous advancement of science and technology, gas injection gas displacement technology has made breakthrough progress from theory to on-site implementation. This technology increases the internal gas pressure of the coal body, accelerates the seepage rate of the mixed gas, injects strong power into the coal seam flow field and forms a reliable gas migration channel, effectively reduces the effective partial pressure of gas, and promotes the desorption of adsorbed gas, thereby solving the problem of insufficient pressure drop in coal seams in the later stage of mining. Therefore, gas injection gas displacement technology has become a key technical means to improve gas extraction efficiency and meet the challenges of deep coal seam mining.

[0039] However, for the regional nitrogen injection to promote extraction in coal seams through directional long drilling, affected by sedimentation, structure, etc., in many cases, the coal seams are not uniformly and stably distributed along the strike. For mineable coal seams, the following situations mainly exist: 1) The thickness of the coal seams is relatively stable, but the coal seams are affected by folds or fault structures and are distributed along the strike with the coal-bearing strata in a wavy or undulating manner; 2) Affected by sedimentation or structure, the thickness of the coal seams changes in a wavy or undulating manner along the strike. 3) For the construction of long-distance drilling, the drill rod is too long, which will cause the borehole to deflect. Therefore, under the condition that the coal seams are distributed in a wavy or undulating manner along the strike, the trajectory of the regional nitrogen injection directional long drilling holes arranged along the strike is bound to show wavy or undulating changes, which is the so-called curved nitrogen injection to promote extraction directional long drilling. For example Figure 1 As shown, Figure 1 This is a schematic diagram of a long curved borehole and water accumulation in a depression.

[0040] At present, regional nitrogen injection to displace water accumulation in directional curved long borehole depressions (mainly including one-time water accumulation caused by hydraulic drilling construction and secondary dynamic water accumulation caused by slow seepage of water-bearing coal and rock layers or other water-bearing geological bodies in the later stage) has the following problems. Figure 1 The curved boreholes shown have different levels of pit water.

[0041] First of all, it will affect the displacement effect. On the one hand, it will reduce the displacement efficiency. Water accumulation or slag clogging at the low point of the borehole will affect the nitrogen injection displacement efficiency and even isolate the high-pressure nitrogen injection. The space occupied by nitrogen will reduce the contact area between nitrogen and gas in the coal seam, making it difficult for nitrogen to effectively displace methane from the coal seam. This will lead to a decrease in displacement efficiency and prolong the displacement time; on the other hand, it will also affect the nitrogen distribution. The presence of water accumulation will change the fluid distribution in the borehole, causing the seepage, diffusion and adsorption process of nitrogen in the coal seam to be disturbed. This may cause nitrogen to be unable to be evenly distributed throughout the coal seam, thereby affecting the displacement effect. In addition, it will also affect the characteristics of the coal seam. On the one hand, it will change the pore structure of the coal seam. Water accumulation in the borehole may have a certain impact on the pore structure of the coal seam, such as causing pore blockage or changing the pore size. This will affect the coal seam's adsorption capacity for methane, thereby affecting the displacement effect. On the other hand, it will affect the permeability of the coal seam. The presence of water accumulation will reduce the permeability of the coal seam, making it difficult for nitrogen to flow smoothly in the coal seam. This will increase the pressure loss during the nitrogen displacement process, thereby reducing the displacement efficiency. These problems will result in poor gas extraction results, and there will also be certain safety issues. If the accumulated water in the borehole is not handled properly, it may cause safety accidents, such as borehole wall collapse or other geological disasters. It may also cause corrosion or damage to the drilling equipment, increase the cost of repairing and replacing equipment, and deteriorate the working environment, increasing the difficulty and danger of the operation.

[0042] In summary, it is particularly important and urgent to solve the problem of water accumulation in depressions in directional long boreholes that are promoted by nitrogen injection in curved areas. However, the current technical methods for borehole drainage in the industry are mainly aimed at ordinary downward boreholes, including gas lift water method, orifice drainage method, deep well pump drainage method in the hole, etc. For the problem of water accumulation in curved long boreholes, the existing technology solves this problem by adding branch holes, but there are also some shortcomings. First, the construction of additional branch boreholes is limited by geological conditions, and its drilling efficiency and success rate will be affected to a certain extent; second, the construction of branch boreholes has certain difficulties in controlling the borehole trajectory, and the trajectory may deviate from the designed path, which will affect the drainage effect and the quality of subsequent projects; at the same time, adding branch boreholes may increase safety risks during construction, such as drill rod bending, borehole collapse, etc.; in addition, the construction cost is increased.

[0043] Based on this, the embodiments of the present invention provide a comprehensive management and control system and method for curved directional long drilling holes in the target coal seam, thereby realizing the integrated management and control of pit water discharge, nitrogen injection displacement and gas extraction in the same borehole and the same pipeline. It can improve the effect of nitrogen injection to increase flow and promote extraction, shorten the construction period, optimize resource allocation, and reduce construction costs.

[0044] Figure 2 A structural schematic diagram of a target coal seam curved directional long drilling integrated control system provided for the implementation of the present invention, see Figure 2 As shown, the above-mentioned target coal seam curved directional long drilling integrated management and control system may include:

[0045] Negative pressure extraction module 11, high pressure nitrogen injection module 12, intelligent control module 13 and multi-effect collaborative pipeline 14; their connection relationship is as follows Figure 2 shown.

[0046] The multi-effect cooperative pipeline 14 is arranged in a curved directional long borehole, and the multi-effect cooperative pipeline 14 includes an inner layer of an inner extraction pipe 141 and an outer layer of an external nitrogen injection pipe 142; wherein the inner extraction pipe 141 is used to extract the accumulated water in the borehole and perform gas extraction operations, and the external nitrogen injection pipe 142 is used to inject nitrogen into the borehole;

[0047] The negative pressure extraction module 11 is used to generate a negative pressure environment and extract the water and gas in the borehole through the inner extraction pipe 141;

[0048] The high-pressure nitrogen injection module 12 is used to provide high-pressure nitrogen and inject nitrogen into the borehole through the external nitrogen injection pipe 142 to achieve the displacement effect of nitrogen and enhance the gas fluidity in the target coal seam;

[0049] The intelligent control module 13 is respectively connected to the negative pressure extraction module 11 , the high pressure nitrogen injection module 12 and the multi-effect collaborative pipeline 14 , and is used for intelligently controlling the working states of the negative pressure extraction module 11 and the high pressure nitrogen injection module 12 .

[0050] The specific process of intelligent control by the intelligent control module 13 includes:

[0051] First, the negative pressure extraction module 11 is started and controlled to extract the accumulated water in the borehole through the internal extraction pipe 141, and the negative pressure extraction module 11 is closed after the accumulated water is extracted; then the high pressure nitrogen injection module 12 is started and controlled to perform nitrogen injection displacement operation through the external nitrogen injection pipe 142, and the high pressure nitrogen injection module 12 is closed after the nitrogen injection displacement operation reaches the preset conditions; finally, the negative pressure extraction module 11 is started and controlled again to extract the gas in the borehole through the internal extraction pipe 141, thereby realizing the integrated management and control of the discharge of accumulated water in the curved directional long borehole pit, nitrogen injection displacement and gas extraction.

[0052] In some embodiments, the internal extraction pipe 141 and the external nitrogen injection pipe 142 can be connected to each other through a separate connecting device 15 .

[0053] Among them, the main body of the separation and connection device is a ventilation double sleeve. Figure 3 FIG. 1 is a schematic diagram of the structure of the main components of the separation and connection device 15 in an embodiment of the present invention. Figure 3 As shown, the double sleeve of the separation connection device 15 includes two independent channels in the inner and outer layers, each of which includes a port at the top and bottom, respectively. Figure 3 Port 151 and port 152 as shown. Figure 3 The separation and connection device of the ventilation double-tube structure shown allows the inner extraction pipe 141 and the outer nitrogen injection pipe 142 to pass through the two independent channels of the double-tube respectively, thereby realizing the spatial separation of the two. At the same time, the necessary connection can be achieved through the upper and lower ports 151 and port 152.

[0054] Figure 4 1 is a schematic diagram of the structure of the separation and connection device 15 in the multi-effect cooperative pipeline 14 of an embodiment of the present invention. Figure 4 As shown, a one-way valve 16 is respectively provided at the upper and lower ports of the separation connection device 15 , and a filter screen 161 is provided at the outer ends of the two one-way valves 16 .

[0055] It can be understood that the design of the one-way valve 16 ensures that the gas or liquid can only flow in one direction, thereby preventing the accumulated water from flowing back into the borehole in the pipe during the drainage process. The filter 161 is arranged at the outer end of the one-way valve 16 to prevent impurities or particles inside and outside the borehole from entering the separation connection device, affecting the normal operation of the one-way valve or causing blockage. The filter 161 can effectively filter out these impurities or particles to ensure the cleanliness and smoothness of the separation connection device 15.

[0056] In some embodiments, the number of the separation connection devices 15 is determined according to the length of the curved directional long borehole;

[0057] Specifically, if the borehole is long, more separation and connection devices 15 need to be provided in the borehole to ensure that the inner extraction pipe 141 and the outer nitrogen injection pipe 142 can maintain stable connection and connection over the entire borehole length, while ensuring the efficiency of the extraction operation and the nitrogen injection operation. If the borehole is short, the number of separation and connection devices 15 can be reduced accordingly.

[0058] In some embodiments, the pipe head of the inner extraction pipe 141 at one end inside the borehole is in a closed state; thereby, the negative pressure extraction module 11 extracts water accumulated in the borehole through the one-way valve into the pipeline, thereby improving drainage efficiency.

[0059] It is understandable that when the negative pressure extraction module 11 starts working, it will generate a negative pressure environment inside the borehole. Since the pipe head is closed, the accumulated water in the borehole can only enter the pipeline through the pre-installed one-way valve. This effectively prevents the possibility of fluid backflow or external impurities entering the borehole. Since the accumulated water can only enter the inner extraction pipe 141 through the one-way valve, the unidirectionality and stability of the fluid flow can be ensured, reducing the risk of reduced extraction efficiency or equipment damage caused by fluid backflow or impurities entering, and improving drainage efficiency.

[0060] In some embodiments, the density of the nitrogen injection ports provided on the external nitrogen injection pipe 142 gradually increases from the outside to the inside of the borehole, that is, as the depth of the borehole increases, the distance between the nitrogen injection ports becomes shorter and shorter, and the arranged nitrogen injection ports become more and more dense.

[0061] It is understandable that the pressure of nitrogen will gradually decrease as it flows in the pipeline. If the distribution of nitrogen injection ports is uneven, especially if there are not enough nitrogen injection ports deep in the borehole, the farthest nitrogen injection port may not be able to effectively inject nitrogen into the borehole due to insufficient nitrogen pressure, thus affecting the nitrogen injection displacement of the entire borehole area. By increasing the density of nitrogen injection ports through components, the injection density of nitrogen in the entire borehole can be uniformed, thereby improving the effect of nitrogen injection displacement operations.

[0062] In some embodiments, the nitrogen injection port may adopt any same or different shapes, such as conical, circular, trumpet-shaped or other shapes that can increase the diffusion area and speed of nitrogen, thereby improving the distribution uniformity and coverage of nitrogen in the borehole.

[0063] In some embodiments, a high-pressure nitrogen injection stop valve 51 and a negative pressure extraction stop valve 52 are provided between the multi-effect collaborative pipeline 14 and the intelligent control module 13 (see Figure 5 shown).

[0064] Among them, the high-pressure nitrogen injection stop valve 51 is used to control the flow and stop of high-pressure nitrogen in the external nitrogen injection pipe 142, and the negative pressure extraction stop valve 52 is used to control the flow and stop of accumulated water or gas in the internal extraction pipe 141;

[0065] Specifically, when the negative pressure extraction module 11 is working, the intelligent control module 13 can automatically control the high-pressure nitrogen injection stop valve 51 to close and the negative pressure extraction stop valve 52 to open; when the high-pressure nitrogen injection module is working, the intelligent control module 13 can automatically control the high-pressure nitrogen injection stop valve 51 to open and the negative pressure extraction stop valve 52 to close.

[0066] In some embodiments, when the multi-effect cooperative pipeline 14 is arranged in a curved directional long borehole, the borehole opening needs to be sealed. The borehole sealing section is arranged between the elastic area and the original stress area in the stress concentration area.

[0067] It is understandable that in order to ensure the effective injection of nitrogen and the stable extraction of gas, while preventing unnecessary exchange of gas or liquid inside and outside the borehole, the borehole mouth needs to be strictly sealed, which is crucial to maintaining the stability and safety of the internal environment of the borehole.

[0068] Exemplarily, in order to achieve the sealing of the borehole, the existing "two plugs and one injection" sealing method can be adopted. The core of this sealing method is that it sets two sealing plugs (usually called "plugs") at specific positions of the borehole, and forms a closed space between the two plugs, namely the sealing section. This sealing section is arranged between the elastic zone and the original stress zone in the stress concentration zone to ensure that the sealing effect of the borehole is optimal. Specifically, the first plug is usually placed near the borehole mouth, and its main function is to initially block the gas or liquid outside the borehole from entering the borehole. The second plug is placed at a certain distance from the first plug to form a relatively closed interval. In this interval, special sealing materials (such as cement slurry, polyurethane foam, etc.) can be injected into the borehole using grouting equipment. These materials will form a strong and dense sealing layer after curing to further prevent gas leakage and exchange. The sealing section is arranged between the elastic zone and the original stress zone in the stress concentration zone. The stress state of the rock formation is relatively stable and not easily disturbed by external factors, thus providing a good curing environment for the sealing material and ensuring the durability and reliability of the sealing effect.

[0069] For example, see also Figure 5 As shown, Figure 5 Schematic diagram of the sealing position in the borehole in the embodiment of the present invention. 53 is the coal seam fracture zone, 54 is a two-blocking and one-injection bag for sealing the borehole in a "two-blocking and one-injection" manner, and 55 is a nitrogen injection port provided on the external nitrogen injection pipe 142.

[0070] It should be noted that there is usually a fracture zone of a certain depth in the coal seam at the borehole mouth, such as Figure 5 The coal seam fracture zone 53 shown is usually accompanied by a large number of cracks and faults. These cracks are not only numerous but also widely distributed. The existence of these cracks seriously damages the integrity of the formation and forms channels for the flow of gas and liquid. Due to the development of cracks, the permeability of the coal seam fracture zone 53 is usually very strong. This means that the gas or liquid inside and outside the borehole can easily exchange through these cracks, thereby increasing the difficulty of sealing the borehole. Therefore, when sealing the borehole, it is necessary to avoid the following Figure 5 The crushing zone 53 area shown in is selected between the elastic zone and the original stress zone within the stress concentration zone as described above.

[0071] In some embodiments, a sensor is provided at the end of the multi-effect cooperative pipeline 14 for real-time monitoring of the pressure and concentration data in the borehole;

[0072] The intelligent control module 13 can determine whether to perform a nitrogen re-injection operation or a drainage operation based on the monitored pressure and concentration data.

[0073] Specifically, if the intelligent control module 13 detects that the extracted gas concentration is reduced or the concentration distribution is uneven, or the nitrogen concentration in the borehole is reduced or the pressure distribution is uneven, indicating that the nitrogen displacement effect may be weakened, the intelligent control module 13 will trigger the nitrogen re-injection operation in time to ensure that the nitrogen can continue to effectively displace the gas from the coal seam.

[0074] In some embodiments, the curved directional long borehole may include multiple holes. Figure 6 As shown, Figure 6 FIG. 2 is a schematic diagram of another integrated control system for curved directional long drilling of target coal seams in an embodiment of the present invention. Figure 6 As shown, the target coal seam includes three curved directional long boreholes 17 (the boreholes are curved in actual application, and are represented by straight lines in the figure for convenience), and the multi-effect coordinated pipelines 14 described above can be evenly arranged in each borehole; a connection regulator 62 is provided between the end 61 of the multi-effect coordinated pipeline 14 in each borehole and the intelligent control module 13. When performing water discharge, nitrogen injection displacement and gas extraction operations, the intelligent control module 13 can control the connection regulator 62 to achieve the replacement of the connection with the end 61, so as to respectively perform gas extraction in each borehole.

[0075] In some embodiments, the intelligent control module 13 determines whether to perform nitrogen re-injection or drainage according to the pressure and concentration data monitored by the sensor. It can also determine which borehole needs nitrogen re-injection or drainage.

[0076] Specifically, the intelligent control module 13 will judge whether the extraction effect has deteriorated and whether to perform nitrogen injection again based on the real-time data of pressure and concentration detected by the sensor of the end 61 of the multi-effect collaborative pipeline 14. When the number of boreholes with deteriorated extraction effect is 0, it indicates that all boreholes do not need to perform secondary nitrogen injection displacement operation, and there is no need to adjust the connection regulator 62; when the number of boreholes with deteriorated extraction effect is 1, it indicates that one borehole needs secondary nitrogen injection displacement operation, and at this time, the connection regulator 62 is adjusted to connect the high-pressure nitrogen injection module 12 to the end 61 of the multi-effect collaborative pipeline 14 in the corresponding borehole; when the number of boreholes with deteriorated extraction effect is greater than 1, it indicates that multiple boreholes need secondary nitrogen injection displacement operation, and it is necessary to adjust the connection regulator 62 in turn to connect the end 61 of the multi-effect collaborative pipeline 14 in the corresponding borehole. The principle of "heavy first and light later" can be adopted at the same time, first connecting the multi-effect collaborative pipeline 14 in the borehole with the worst extraction effect, and then connecting the multi-effect collaborative pipelines 14 in other boreholes in turn.

[0077] In some embodiments, the connection regulator 62 is also used to indirectly achieve the effect of pulse nitrogen injection when performing nitrogen injection displacement operations.

[0078] For details, see Figure 6 As shown, the connection regulator 62 can select the end 61 for establishing a connection relationship between the three multi-effect collaborative pipelines 14 periodically or randomly according to a preset program or according to instructions from the intelligent control module 13, so that nitrogen can be injected into the borehole and coal seam in the form of pulses.

[0079] Under the action of nitrogen pulses, the pores and cracks in the coal body are forced to undergo a dynamic process of expansion-contraction-re-expansion-re-contraction. This periodic stress change causes fatigue damage inside the coal body, which in turn promotes the penetration of internal pores, the development, expansion and regeneration of cracks. These changes greatly improve the gas migration channel and reduce the migration resistance of the mixed gas, thereby accelerating the diffusion and seepage rate of coal body gas, thereby achieving a considerable purpose of promoting the discharge / extraction of gas. In addition, pulse nitrogen injection also helps to evenly distribute nitrogen in the coal seam. By periodically injecting nitrogen, local accumulation of nitrogen in the coal seam can be avoided, ensuring that nitrogen can fully contact the gas in the coal seam and effectively displace it. This uniform nitrogen distribution not only improves the displacement efficiency, but also shortens the displacement time.

[0080] In the second aspect, an embodiment of the present invention further provides a method for comprehensive control of curved directional long drilling holes in a target coal seam, which can be applied to the comprehensive control system for curved directional long drilling holes in a target coal seam provided in the first aspect. Figure 7 FIG. 1 is a flow chart of an embodiment of a method for comprehensive control of a target coal seam curved directional long drilling hole in an embodiment of the present invention. Figure 7 As shown, the above method may include:

[0081] S701, design a curved directional long drilling trajectory according to the preset nitrogen injection displacement flow increase and pumping promotion target, the coal and rock formation strike and occurrence conditions of the target working face, and the performance of the directional drilling construction equipment;

[0082] Among them, the clear preset nitrogen injection displacement flow increase and extraction promotion goals are the basis of the entire design process. For example, it includes specific indicators such as the expected gas extraction volume, the degree of gas concentration reduction, and the nitrogen injection displacement effect. These goals will directly guide the design of the drilling trajectory to ensure that the drilling can accurately act on the target coal seam and achieve the expected gas extraction effect.

[0083] The orientation and occurrence conditions of the coal and rock formations at the target working face are important factors that must be considered when designing the drilling trajectory. The inclination, thickness, joint development, and geological structure of the coal and rock formations will directly affect the construction difficulty and gas extraction efficiency of the drilling. Therefore, during the design process, it is necessary to fully understand the geological conditions of the target working face and conduct a comprehensive analysis based on the actual situation to determine the best drilling trajectory.

[0084] In addition, the performance of directional drilling equipment is also a factor that cannot be ignored when designing the drilling trajectory. The drilling capacity, guidance accuracy and stability of the equipment will directly affect the quality and efficiency of drilling. Therefore, when designing the drilling trajectory, it is necessary to fully consider the performance characteristics of the equipment to ensure that the drilling trajectory can be achieved within the capacity of the equipment and to maximize the construction efficiency and quality.

[0085] Taking the above factors into consideration, scientific methods and means, such as geological exploration, numerical simulation, and optimization design, are used when designing the curved directional long drilling trajectory to ensure that the drilling trajectory can meet the preset nitrogen injection displacement flow increase and pumping promotion goals.

[0086] S702, drilling construction is performed according to the designed module curved directional long drilling trajectory, and after the drilling is completed, the module multi-effect collaborative pipeline is arranged in the long drilled hole;

[0087] In some embodiments, the multi-effect cooperative pipeline can be pre-placed inside the drill rod. During the drilling process, the multi-effect cooperative pipeline can enter the curved directional long borehole synchronously with the drill rod. After the drilling construction is completed, the drill rod and the drill bit are withdrawn, and the multi-effect cooperative pipeline can be left in the borehole. In this way, the construction process is greatly simplified, avoiding the complexity and potential risks of pipeline installation after the drilling is completed.

[0088] In other embodiments, the multi-effect coordinated pipeline can also be arranged in the borehole after the curved directional long drilling construction is completed. It is understandable that although this method requires additional construction steps and may face higher technical challenges compared to synchronous built-in pipelines, it can provide flexibility for handling special terrain, adjusting pipeline layout or responding to emergencies.

[0089] It should be noted that since the pipeline layout after drilling requires additional construction and the pipeline layout in the borehole is difficult, in a preferred embodiment of the present invention, the multi-effect cooperative pipeline can be directly inserted into the borehole synchronously with the drill rod and the drill bit.

[0090] S703, sealing the drilled hole between the elastic zone of the stress concentration zone and the original stress zone;

[0091] Specifically, the above-mentioned "two blocking and one injection" method can be adopted. After each hole is drilled, the casing is immediately sealed. Expansive cement can be used, and the sealing length can be determined based on experience. For example, it should not be less than 30m. The "two blocking and one injection" sealing method is used to arrange the drilling sealing section between the elastic area of ​​the stress concentration area and the original stress area; the pressure in the borehole is measured using a pressure gauge, and the integrity of the air tightness is checked.

[0092] S704, close the negative pressure extraction stop valve, open the high-pressure nitrogen injection stop valve, start and control the operation of the negative pressure extraction module, and discharge the accumulated water in the borehole through the internal extraction pipe; when it is determined that the water extraction is completed according to the flow data of the internal extraction pipe, close the negative pressure extraction module, open the negative pressure extraction stop valve, close the high-pressure nitrogen injection stop valve, start and control the operation of the high-pressure nitrogen injection module, and perform nitrogen injection displacement operation through the external nitrogen injection pipe; after the nitrogen injection displacement operation reaches the preset conditions, close the high-pressure nitrogen injection module, close the negative pressure extraction stop valve, open the high-pressure nitrogen injection stop valve, start and control the operation of the negative pressure extraction module, and perform gas extraction operation through the internal extraction pipe, so as to realize the integrated management and control of the discharge of accumulated water in the curved directional long borehole pit, nitrogen injection displacement and gas extraction.

[0093] For example, the state changes of the multi-effect synergistic pipeline during the process of water discharge, nitrogen injection displacement and gas extraction through the above-mentioned target coal seam curved directional long drilling integrated control method can be seen in Figures 8 to 11 As shown, Figure 8 FIG. 1 is a schematic diagram of the structure of the multi-effect cooperative pipeline pumping process at the beginning of the embodiment of the present invention; see Figure 8 As shown, the accumulated water in the borehole enters the inner extraction pipe 141 through the one-way valve 16. Fig. 9 This is a structural schematic diagram of the multi-effect cooperative pipeline pumping process in the embodiment of the present invention; see Fig. 9 As shown, the accumulated water is pumped out through the inner pumping pipe 141.

[0094] Fig.10 is a structural schematic diagram of the multi-effect coordinated pipeline nitrogen injection displacement process in an embodiment of the present invention; see Fig.10 As shown, nitrogen enters the borehole from the nitrogen injection port 55 of the external nitrogen injection pipe 142, thereby displacing the gas in the coal seam.

[0095] Fig.11 Schematic diagram of the structure of the multi-effect coordinated pipeline gas extraction process in the embodiment of the present invention. Fig.10 As shown, after the nitrogen injection displacement effect is completed, the gas is also extracted by entering the inner extraction pipe 141 through the one-way valve 16, and then extracted out through the inner extraction pipe 141.

[0096] In some embodiments, the nitrogen injection displacement operation reaches the preset condition by staying for a period of time after the nitrogen injection displacement operation is completed, so that the nitrogen can fully exert its displacement effect in the coal seam and release as much gas as possible from the coal seam. Alternatively, the nitrogen injection displacement operation reaches the preset condition by directly detecting the gas concentration in the flow state, and when the gas concentration in the flow state reaches the preset value, gas extraction can be carried out.

[0097] The nitrogen injection displacement operation reaches the preset condition mainly to determine whether the nitrogen injection displacement is completed, as a judgment condition for whether gas extraction can be performed. The selection of the preset condition does not limit the scope of the present invention, so the embodiment of the present invention does not specifically limit this.

[0098] It should be noted that the specific execution process and achievable functions of the method for comprehensive control of curved directional long drilling of target coal seams can be specifically referred to the description of the functions of each functional module in the above-mentioned comprehensive control system for curved directional long drilling of target coal seams, and the embodiments of the present invention will not elaborate on this.

[0099] In the embodiment of the present invention, the multi-effect collaborative pipeline can be applied to most curved long boreholes, and can flexibly respond to various complex and changeable geological environments, ensuring that whether in a long winding borehole or in an environment facing extreme geological challenges, the efficient implementation of the nitrogen injection flow-increasing and pumping-promoting project can be achieved, thereby meeting the diversified needs of geological exploration and engineering implementation. In addition, the construction requirements of redundant branch boreholes in the drainage operation of the traditional curved directional long borehole are avoided, which not only reduces the potential damage to the geological structure, but also effectively improves the overall construction efficiency. By reducing unnecessary drilling operations, not only the natural state of underground resources is protected, but also the practice of environmentally friendly construction concepts is promoted. In addition, through the multi-effect collaborative pipeline, the pit drainage operation of the inner extraction pipe is first carried out, followed by the nitrogen injection displacement operation of the external nitrogen injection pipe, and finally the gas extraction operation of the inner extraction pipe is carried out, so as to realize the integrated management and control of the pit water discharge, nitrogen injection displacement and gas extraction of the same borehole and the same pipeline. The multi-effect implementation of drilling operations solves the problem of time waste caused by arranging the water pumping pipeline first and then the nitrogen injection pipeline in traditional operations, greatly shortening the overall construction period of the project; by efficiently integrating the construction steps, it not only greatly reduces the occupation time of construction equipment, but also effectively optimizes resource allocation, further reduces construction costs, and improves the economic benefits of the project. In addition, through the linkage between the intelligent control module system and the connection regulator, pulse nitrogen injection can be indirectly achieved to improve the efficiency of gas extraction. The multifunctional integration of the integrated management and control system for water discharge, nitrogen injection displacement and gas extraction can reduce manpower operation time and reduce the time underground workers are exposed to potentially dangerous environments, thereby effectively reducing the risk of accidents during operations.

[0100] The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referenced to each other. Each embodiment focuses on the differences from other embodiments.

[0101] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit the present application. Although the present application has been described in detail with reference to the aforementioned embodiments, a person of ordinary skill in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some or all of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the present application.

Claims

1. A comprehensive management and control system for curved directional long drilling of target coal seams, characterized in that: include: Negative pressure extraction module, high pressure nitrogen injection module, intelligent control module and multi-effect collaborative pipeline; The multi-effect coordinated pipeline is arranged in a curved directional long borehole, and includes an inner extraction pipe of an inner layer and an outer nitrogen injection pipe of an outer layer; wherein the inner extraction pipe is used to extract the accumulated water in the borehole and perform gas extraction operations, and the outer nitrogen injection pipe is used to inject nitrogen into the borehole; The negative pressure extraction module is used to generate a negative pressure environment and realize the extraction of water and gas in the borehole through the inner extraction pipe; The high-pressure nitrogen injection module is used to provide high-pressure nitrogen and inject nitrogen into the borehole through the external nitrogen injection pipe to achieve nitrogen displacement and enhance gas fluidity in the target coal seam; The intelligent control module is respectively connected to the negative pressure extraction module, the high-pressure nitrogen injection module and the multi-effect collaborative pipeline, and is used for intelligently controlling the working states of the negative pressure extraction module and the high-pressure nitrogen injection module; wherein, the specific process of intelligent control includes: first, starting and controlling the operation of the negative pressure extraction module, extracting the accumulated water in the borehole through the internal extraction pipe, and closing the negative pressure extraction module after the accumulated water is extracted; then starting and controlling the operation of the high-pressure nitrogen injection module, performing nitrogen injection displacement operation through the external nitrogen injection pipe, and closing the high-pressure nitrogen injection module after the nitrogen injection displacement operation reaches the preset conditions; finally, starting and controlling the operation of the negative pressure extraction module again, extracting the gas in the borehole through the internal extraction pipe, thereby realizing the integrated management and control of the discharge of accumulated water in the curved directional long borehole pit, nitrogen injection displacement and gas extraction.

2. The integrated management and control system according to claim 1, characterized in that: The inner extraction pipe and the outer nitrogen injection pipe are connected and interconnected via a separation connection device, the number of which is determined according to the length of the curved directional long borehole; the main body of the separation connection device is a ventilation double sleeve, and a one-way valve is provided at each of the upper and lower ports, and filters are provided at the outer ends of the two one-way valves.

3. The integrated management and control system according to claim 2, characterized in that: A high-pressure nitrogen injection stop valve and a negative pressure extraction stop valve are arranged between the multi-effect collaborative pipeline and the intelligent control module; the high-pressure nitrogen injection stop valve is used to control the flow and stop of the high-pressure nitrogen in the external nitrogen injection pipe, and the negative pressure extraction stop valve is used to control the flow and stop of the accumulated water or gas in the internal extraction pipe; when the negative pressure extraction module is working, the high-pressure nitrogen injection stop valve is closed and the negative pressure extraction stop valve is opened; when the high-pressure nitrogen injection module is working, the high-pressure nitrogen injection stop valve is opened and the negative pressure extraction stop valve is closed.

4. The integrated management and control system according to claim 3, characterized in that: The multi-effect collaborative pipeline end is provided with a sensor for real-time monitoring of the pressure and concentration data in the borehole; the intelligent control module determines whether to perform re-nitrogen injection operation or re-drainage operation based on the monitored pressure and concentration data.

5. The integrated management and control system according to claim 4, characterized in that: The curved directional long boreholes include a plurality of boreholes, each of which is provided with the multi-effect coordinated pipeline; A connection regulator is provided between the plurality of multi-effect collaborative pipelines and the intelligent control module, and the intelligent control module can control the connection regulator to achieve replacement of the connection points with the end heads of each multi-effect collaborative pipeline.

6. The integrated management and control system according to claim 5, characterized in that: The connection regulator is also used to indirectly achieve the effect of pulse nitrogen injection when performing nitrogen injection displacement operations.

7. The integrated management and control system according to claim 6, characterized in that: The pipe head of the inner extraction pipe is in a closed state; in the direction from the outside to the inside of the borehole, the density of the nitrogen injection ports arranged on the outer nitrogen injection pipe gradually increases.

8. The integrated management and control system according to claim 7, characterized in that: The sealing section of the curved directional long borehole is arranged between the elastic zone and the original stress zone of the stress concentration zone.

9. A method for comprehensive control of curved directional long drilling of a target coal seam, applied to the comprehensive control system according to any one of claims 1 to 8, characterized in that: include: According to the preset nitrogen injection displacement flow increase and pumping promotion target, the coal and rock formation strike and occurrence conditions of the target working face, and the performance of the directional drilling construction equipment, a curved directional long drilling trajectory is designed; Drilling is performed according to the designed curved directional long drilling trajectory, and after the drilling is completed, the multi-effect collaborative pipeline is arranged in the long drilled hole; Sealing the drilled hole between the elastic zone and the original stress zone in the stress concentration area; Close the negative pressure extraction stop valve, open the high pressure nitrogen injection stop valve, start and control the operation of the negative pressure extraction module, and discharge the accumulated water in the borehole through the inner extraction pipe; when it is determined that the water extraction is completed according to the flow data of the inner extraction pipe, close the negative pressure extraction module, open the negative pressure extraction stop valve, close the high pressure nitrogen injection stop valve, start and control the operation of the high pressure nitrogen injection module, and perform nitrogen injection displacement operation through the external nitrogen injection pipe; after the nitrogen injection displacement operation reaches the preset conditions, close the high pressure nitrogen injection module, close the negative pressure extraction stop valve, open the high pressure nitrogen injection stop valve, start and control the operation of the negative pressure extraction module, and perform gas extraction operation through the inner extraction pipe, so as to realize the integrated management and control of the discharge of accumulated water in the curved directional long borehole pit, nitrogen injection displacement and gas extraction.

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