Coal mine resource collaborative exploitation and mining surrounding rock full space destruction control method

Abstract

The present application relates to the technical field of coal mining, and provides a coal mine resource collaborative mining and full-space destruction control method for surrounding rock in a mining area, comprising the following steps: determining the horizon of a low-position thick hard basic roof rock layer based on the structural parameters of a coal seam roof; determining the arrangement position and parameters of a fracturing borehole based on the horizon of the low-position thick hard basic roof rock layer; performing fracturing borehole construction, with the horizontal section of the fracturing borehole being located in the low-position thick hard basic roof rock layer and covering the entire length of the mining face in the strike direction; performing fracturing construction in the horizontal section to form fracturing cracks and controlling the development of the fracturing cracks to make the fracturing cracks penetrate the coal seam in the vertical direction; and after the fracturing construction is completed, extracting gas through the fracturing borehole. In this way, by using the fracturing of the low-position thick hard basic roof rock layer, the coal seam gas resource recovery, gas disaster control, coal mine roof / floor water disaster prevention and control, and surrounding rock control in the mining and excavation space can be simultaneously achieved, the disaster prevention and control engineering quantity is greatly reduced, the engineering cost is reduced, and the construction period is shortened.

Description

Technical Field

[0001] This invention relates to the technical field of coal mining, and in particular to a method for coordinated mining of coal resources and full-space control of mining-induced surrounding rock damage. Background Technology

[0002] Coal seam mining disrupts the original equilibrium of the strata. Under the stress concentration and unloading effects of mining, the roof, floor, and surrounding rock of the coal seam will all experience a series of failures. Roof strata failure leading to aquifers will induce roof water hazards and loss of roof water resources; floor strata failure leading to aquifers will induce floor water hazards; stress concentration in the surrounding rock of the mining space will induce roadway failure; and dynamic loads and high mine pressures will manifest in the mining space. Simultaneously, coal metamorphism often produces large amounts of methane, which accumulates in the coal seam. During coal seam mining, this methane will be released into the mining space, easily causing methane accumulation and inducing methane explosions. When the methane content in the coal seam is high and the pressure is excessive, even coal and gas outbursts may occur. While coal seam methane can be used as a clean energy source when fully utilized, its greenhouse effect is approximately twenty times that of carbon dioxide if emitted in an uncontrolled manner.

[0003] Currently, methods for coal seam gas resource recovery and disaster prevention mainly include pre-mining coal seam drilling and extraction, hydraulic fracturing and extraction, and water jet extraction from coal seams. Roof water hazard prevention and water resource protection in coal mines mainly involve pre-mining water drainage, partial mining, backfilling mining, and other methods to control overburden damage, as well as grouting and sealing of passageways and grouting modification of aquifers. Floor water hazard control mainly employs methods such as regional and local grouting reinforcement of the floor and floor water drainage. Large-scale damage and dynamic disasters in the surrounding rock of mining spaces induced by stress concentration and large-area instability are mainly prevented by strengthening support, roadway drilling for pressure relief, hydraulic fracturing and pressure relief of the roof strata, and rational layout of mining spaces.

[0004] However, there is still a lack of comprehensive, efficient, proactive, and economical means to address the aforementioned issues of surrounding rock damage caused by coal mining and the recovery of associated gas resources. Summary of the Invention

[0005] This invention provides a method for coordinated mining of coal resources and full-space destruction control of surrounding rock during mining, which solves the problem that it is difficult to achieve gas development and utilization and disaster prevention in an economical and efficient manner in the existing technology. It can achieve efficient and economical gas extraction and destruction control of roof and floor as well as surrounding rock in mining space.

[0006] This invention provides a method for coordinated mining of coal resources and full-space damage control of surrounding rock caused by mining, comprising the following steps:

[0007] Based on the structural parameters of the coal seam roof, the stratigraphic position of the low-lying, thick, hard basic roof strata is determined.

[0008] Based on the stratigraphic position of the aforementioned low-lying, thick, and hard underlying rock layer, the location and parameters of the fracturing boreholes are determined.

[0009] The horizontal section of the fracturing borehole is located within the low-lying, thick, hard, basic top rock layer and covers the entire length of the mining face in terms of its strike.

[0010] Fracturing operations are performed in the horizontal section to form fracturing fractures, and the development of the fracturing fractures is controlled so that the fracturing fractures penetrate the coal seam vertically.

[0011] After the fracturing operation is completed, gas is extracted through the fracturing borehole.

[0012] According to the present invention, a method for coordinated mining of coal resources and full-space destruction control of surrounding rock during mining is provided, wherein the fracturing borehole is an "L-shaped" borehole on the ground.

[0013] The fracturing borehole includes a vertical section perpendicular to the low-lying, thick, hard base rock stratum, a horizontal section extending along the strike of the low-lying, thick, hard base rock stratum, and a sloping section for connecting the vertical section and the horizontal section.

[0014] According to the present invention, a method for coordinated mining of coal resources and full-space failure control of surrounding rock during mining is provided, wherein determining the layout location and parameters of fracturing boreholes includes:

[0015] If it is determined that the horizontal section of a single fracturing borehole cannot control the entire working face length, two or more fracturing boreholes are arranged in the working face length direction.

[0016] According to the present invention, a method for coordinated mining of coal resources and full-space destruction control of surrounding rock during mining is provided. When it is determined that the horizontal section of a single fracturing borehole cannot control the entire working face length, two fracturing boreholes are arranged in the working face length direction. The two fracturing boreholes are constructed on the cutting side and the stop line side, respectively.

[0017] According to the present invention, a method for coordinated mining of coal resources and full-space failure control of surrounding rock during mining is provided, wherein determining the layout location and parameters of fracturing boreholes includes:

[0018] During fracturing, monitor the development of the fracturing fractures;

[0019] The degree of fracturing, the effect of fracturing on the coal seam, and the horizontal distribution of the fracturing fractures are determined based on the development of the fracturing fractures.

[0020] Based on the horizontal distribution of the fracturing fractures, the horizontal spacing between adjacent fracturing boreholes is determined so that the fracturing fractures can cover the entire mining area.

[0021] According to the present invention, a method for coordinated mining of coal resources and full-space destruction control of surrounding rock during mining is provided, wherein the structural parameters of the coal seam roof include: the thickness of each stratum and the rock mechanical properties.

[0022] According to the present invention, a method for coordinated mining of coal resources and full-space destruction control of surrounding rock during mining is provided, wherein determining the stratigraphic position of the low-lying, thick, hard, basic roof strata includes:

[0023] Based on the thickness of each stratum and the mechanical properties of the rock, the key layer theory was used to conduct structural analysis of each stratum in the top plate to determine the strata of the low-lying, thick, and hard basic top stratum.

[0024] According to the present invention, a method for coordinated mining of coal resources and full-space failure control of surrounding rock during mining is provided, wherein hydraulic fracturing is performed in the horizontal section to form hydraulic fractures, including:

[0025] Hydraulic fracturing operations are carried out in the horizontal section of the fracturing borehole, and hydraulic fracturing is performed in sections on the low-lying thick and hard basic top rock layer to form a hydraulic fracture network.

[0026] According to the present invention, a method for co-mining coal resources and controlling the destruction of surrounding rock in the whole space during mining is provided, wherein secondary fracturing is performed when the fracturing effect does not meet the requirements.

[0027] According to the present invention, a method for co-mining coal resources and controlling the full-space damage of surrounding rock during mining is provided, wherein the development of fracturing fractures is controlled by adjusting the viscosity of fracturing fluid, the pump pressure and discharge rate of fracturing pump, and by temporary plugging.

[0028] This invention provides a method for coordinated mining of coal resources and full-space destruction control of surrounding rock during mining. It involves large-scale hydraulic fracturing of the overburden before mining to modify the permeability and strength of the rock strata and coal seam. The fracturing boreholes are drilled within the low-lying, thick, and hard basic roof strata, where the rock strength and stability are high. This significantly reduces the risk of borehole collapse during gas drainage, improves gas release efficiency, reduces gas pressure, effectively prevents outburst risks during coal seam exposure, and reduces gas emissions during coal seam excavation. The fracturing creates numerous cracks in the roof strata, significantly weakening their strength and integrity. Under the stress of mining support, the fracturing strata can be further broken up. After coal seam extraction, it will collapse and accumulate randomly in the goaf, effectively reducing the overburden length and utilizing the fully broken and randomly accumulated rock strata to support the overburden and promote goaf stress recovery. Furthermore, while reducing support stress, minimizing damage to the surrounding rock in the mining space, and preventing dynamic disasters, it also reduces the height of overburden destruction and the depth of floor destruction, and decreases the amount of water flowing into the roof and floor. This enables efficient and economical control of coal mine gas extraction and the destruction of the roof, floor, and surrounding rock in the mining space. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0030] Figure 1 It is a schematic diagram of the stress concentration distribution and surrounding rock failure characteristics of the mining-induced overburden structure.

[0031] Figure 2 This is a flowchart of the method for collaborative mining of coal resources and full-space destruction control of surrounding rock during mining, provided in an embodiment of the present invention.

[0032] Figure 3 This is a schematic diagram of hydraulic fracturing of a thick, hard base rock stratum provided in an embodiment of the present invention.

[0033] Figure 4 A schematic diagram of the whole-space surrounding rock damage control by the fracturing structure of thick and hard overburden provided in this embodiment of the invention. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0035] To better understand the method for coordinated mining of coal resources and full-space destruction control of surrounding rock during mining provided in this invention, its application background is first introduced. After coal seam mining, the original equilibrium state of the strata will be disrupted. Under the stress concentration and unloading effects of mining, the roof, floor, and surrounding rock of the coal seam will all experience a series of damages, which will induce disasters such as roof water hazards, floor water hazards, and roadway damage. At the same time, the gas in the coal seam is prone to induce gas explosions. When the gas content in the coal seam is high and the pressure is too great, coal and gas outbursts may even occur (specifically, as shown in the figure). Figure 1 (As shown).

[0036] In related technologies, methods for coal seam gas resource recovery and disaster prevention mainly include pre-mining coal seam drilling and extraction, hydraulic fracturing and extraction, and water jet extraction from coal seam boreholes. Roof water hazard prevention and water resource protection in coal mines mainly involve pre-mining water drainage, partial mining, backfilling mining, and other methods to control overburden damage, as well as grouting and sealing of passageways and grouting modification of aquifers. Floor water hazard prevention mainly employs methods such as regional and local grouting reinforcement of the floor and floor water drainage. Large-scale damage and dynamic disasters in the surrounding rock of mining spaces induced by stress concentration and large-area instability are mainly prevented by strengthening support, roadway drilling for pressure relief, hydraulic fracturing and pressure relief of the roof strata, and rational layout of mining spaces.

[0037] Among the aforementioned technologies, gas development and utilization and disaster control methods are mainly carried out in coal seams. However, coal seams are often highly plastic, and especially under high gas pressure and high ground stress conditions, boreholes in coal seams are prone to collapse. Water pressure fractures in coal seams are also prone to failure under stress and coal dust blockage, making it difficult to achieve efficient gas extraction and efficient gas disaster prevention and control.

[0038] In the methods of roof water hazard prevention and control, water release often leads to excessive release and water resource loss. Existing low-loss mining methods such as limited thickness mining, strip mining, and backfilling mining are often costly, affect production, and reduce recovery rate.

[0039] Among the existing methods for preventing and controlling water hazards in coal mine floors, regional grouting treatment is costly and often has blind spots, making it difficult to achieve the desired treatment effect.

[0040] Among the existing methods for controlling the destruction of mining spaces and dynamic disasters, local reinforcement of support and borehole decompression often fail to achieve the desired effect, hydraulic fracturing of the roof decompression is often rather haphazard, and reasonable layout of mining spaces often fails to fully achieve the expected results.

[0041] Therefore, there is still a lack of comprehensive, efficient, proactive, and economical means to address the aforementioned issues of surrounding rock damage caused by coal mining and the recovery of associated gas resources.

[0042] To address the aforementioned technical problems, this invention provides a method for coordinated mining of coal resources and full-space destruction control of surrounding rock during mining, which can efficiently and economically achieve coal mine gas extraction and destruction control of the roof, floor, and mining space surrounding rock.

[0043] The following is combined Figures 2-4 This invention describes a method for coordinated mining of coal resources and full-space destruction control of surrounding rock during mining.

[0044] Figure 1 This is a schematic flowchart of the method for coordinated mining of coal resources and full-space damage control of surrounding rock provided in an embodiment of the present invention, as shown below. Figure 1 As shown, the method includes the following steps:

[0045] Step 10: Based on the structural parameters of the coal seam roof, determine the stratigraphic position of the low-lying, thick, hard basic roof strata.

[0046] Specifically, the structural parameters of the coal seam roof include the thickness of each stratum and the mechanical characteristics of the rock. Based on the borehole columnar section of the mining area, the thickness of each stratum and the mechanical characteristics of the rock are statistically analyzed. The distribution of the key overburden strata is derived using the key stratum theory, thereby determining the strata of the low-lying, thick, and hard basic roof strata.

[0047] Step 11: Based on the stratigraphic position of the low-lying, thick, hard, basic top rock layer, determine the layout and parameters of the fracturing boreholes.

[0048] Specifically, after determining the stratigraphic position of the low-lying, thick, hard base rock stratum, the layout and parameters of the fracturing boreholes are designed. The fracturing boreholes are "L-shaped" boreholes constructed on the ground, meaning that the location and parameters of the fracturing boreholes are designed at the ground position corresponding to the coal mining face. The fracturing borehole includes a vertical section perpendicular to the low-lying, thick, hard base rock stratum, a horizontal section extending along the strike of the low-lying, thick, hard base rock stratum, and a directional drilling section used to connect the vertical and horizontal sections. The depth of the vertical section, the length of the horizontal section, and the turning radius of the directional drilling section need to be designed in conjunction with the actual geological conditions, and no specific limitations are imposed in this embodiment of the invention.

[0049] It should be noted that the construction of "L-shaped" boreholes is a mature existing technology. Therefore, the equipment and specific construction methods used in the construction of "L-shaped" boreholes will not be described in detail in the embodiments of this invention.

[0050] Step 12: Conduct fracturing drilling. The horizontal section of the fracturing borehole is located within the low-lying, thick, hard basic top rock layer and covers the entire length of the longwall mining face in terms of its strike.

[0051] Step 13: After the fracturing borehole construction is completed, fracturing construction is carried out in the horizontal section to form fracturing fractures. The development of fracturing fractures is controlled so that the fracturing fractures penetrate the coal seam vertically.

[0052] Specifically, hydraulic fracturing operations are carried out in the horizontal section of the fracturing borehole. The hydraulic fracturing operations are carried out in sections on the low-lying thick and hard basic roof rock layer to form a hydraulic fracture network. The development of fractures can be controlled by adjusting the viscosity of the fracturing fluid, the pressure and discharge rate of the fracturing pump, and temporary plugging, so that the fracturing fractures penetrate the coal seam vertically and fully pre-fracture and weaken the low-lying thick and hard basic roof rock layer.

[0053] Step 14: After the fracturing operation is completed, gas is extracted through the fracturing borehole. After the fracturing operation is completed, negative pressure is applied to the fracturing borehole to continuously extract gas from the coal seam.

[0054] Specifically, refer to Figure 3 and Figure 4After the fracturing borehole is completed, fracturing is carried out in the horizontal section of the borehole. The fracturing fractures enter the coal seam and form complex fractures in the roof strata. The fracturing fractures can significantly increase the permeability of the coal and rock, reduce the structural integrity and overall strength of the roof strata. After the fracturing is completed, gas drainage is carried out through the "L-shaped" fracturing borehole. Because the fracturing borehole is located inside the low-lying, thick, and hard basic roof strata, the rock strata have high strength and good stability, which greatly reduces the risk of borehole collapse during gas drainage, improves gas release efficiency, reduces gas pressure, effectively prevents the risk of outbursts during coal seam exposure, and reduces the amount of gas emitted during coal seam mining. In addition, because the borehole is a surface "L-shaped" borehole, air will not be mixed in during gas drainage to reduce the gas concentration, which can effectively increase the concentration of extracted gas and increase the utilization rate of extracted gas.

[0055] Furthermore, the fracturing process creates numerous fracturing fractures within the rock mass. The cutting action of these fractures and the interaction between the fracturing fluid and the rock mass weaken its strength and integrity. This causes the original, periodically fractured roof strata, which would normally exhibit periodic fracturing after coal seam extraction, to be fully destroyed under the stress of mining support, collapsing as mining progresses. On one hand, the collapse of the thick, hard roof strata as mining progresses effectively reduces the overhang of the roof strata, decreasing stress concentration in the mining space caused by the stress within the overhanging strata. On the other hand, the collapsing, thick, hard roof strata will accumulate haphazardly in the goaf. The coefficient of fragmentation of this haphazardly accumulated rock mass is significantly greater than that of the periodically fractured, neatly accumulated rock mass. This haphazardly accumulated rock mass is a typical strain-hardening material; that is, when pressure is applied to it, its bearing capacity increases with the increase of deformation under load. Therefore, this haphazardly accumulated rock mass can provide timely support to the overlying strata, reducing the subsidence of the overlying strata and mitigating the risk of dynamic pressure generated by large-area shear failure, while simultaneously controlling overlying strata damage and mining space pressure.

[0056] The cause of floor failure in coal mining lies in the redistribution of mining-induced stress around the mining space, creating supporting stress, while a stress relief zone forms in the goaf after coal seam extraction. Under the influence of the significant stress difference between the stress-increasing and stress-relief zones, the boundary rock mass of the mining space undergoes shear slip failure, leading to instability and failure of the concealed floor structures. Therefore, controlling coal seam floor failure should begin with reducing the magnitude of supporting stress and promoting stress recovery in the goaf.

[0057] As mentioned above, after hydraulic fracturing, the roof strata will collapse as mining progresses, significantly reducing the overhang distance and effectively controlling the stress on the mining support. Furthermore, the collapse of the roof strata during mining allows for timely filling of the goaf, promoting stress recovery in the goaf strata. Therefore, large-scale hydraulic fracturing of the roof strata can effectively reduce the stress difference at the boundary of the mining space, achieving the effect of controlling damage to the coal seam floor.

[0058] Compared with related technologies, the coal mine resource collaborative mining and mining-induced surrounding rock full-space damage control method provided by the embodiments of the present invention can simultaneously realize coal seam gas resource recovery, gas disaster control, coal mine roof / floor water hazard prevention and control, and mining space surrounding rock control by using the fracturing energy of the low-level thick and hard basic roof rock layer. This significantly reduces the amount of disaster prevention and control engineering, reduces engineering costs, and shortens the construction period.

[0059] In one embodiment of the present invention, step 11 includes:

[0060] Step 110: If the horizontal section of a single fracturing borehole cannot control the entire working face length, arrange two or more fracturing boreholes along the length of the working face so that the fracturing boreholes can cover the entire working face in the length direction and reduce blind spots.

[0061] As a specific embodiment of the present invention, when it is determined that the horizontal section of a single fracturing borehole cannot control the entire working face length, two fracturing boreholes can be arranged in the working face length direction, with the two fracturing boreholes being constructed on the side of the cut-in line and the stop-mining line, respectively.

[0062] In one embodiment of the present invention, step 11 further includes:

[0063] Step 111: Detect the development of fracturing fractures during fracturing.

[0064] Step 112: Determine the degree of fracturing, the effect of fracturing on the coal seam, and the horizontal distribution of fracturing fractures based on the development of the fracturing fractures.

[0065] Step 113: Based on the horizontal distribution of the fracturing fractures, determine the spacing between adjacent fracturing boreholes so that the fracturing fractures can cover the entire mining area.

[0066] Specifically, before coal seam mining, "L-shaped" fracturing boreholes are constructed on the surface. The horizontal landing point of the fracturing boreholes is located within the low-lying, thick, and hard basic roof strata, and axially covers the entire length of the mining face. After the "L-shaped" boreholes are constructed, hydraulic fracturing is performed. The fracturing parameters are adjusted to ensure that the fracturing fractures can penetrate the coal seam while effectively reducing the integrity and overall strength of the roof strata. During fracturing, the development of the fracturing fractures is monitored to determine the degree of fracturing, the effect of fracturing on the coal seam, and the horizontal distribution of the fracturing fractures. Then, based on the horizontal distribution of the fracturing fractures, the horizontal spacing between adjacent fracturing boreholes is determined. The fracturing fractures generated by adjacent fracturing boreholes should be interconnected to form a continuous fracturing fracture network, ensuring that the fracturing fractures cover the entire mining area in both the longitudinal and transverse directions, avoiding blind spots, and preventing overlapping fractures that waste resources. A reasonable borehole spacing design can ensure the effectiveness of fracturing operations while reducing unnecessary costs and environmental impacts.

[0067] In one embodiment of the present invention, the method for coordinated mining of coal resources and full-space damage control of surrounding rock during mining further includes the following steps:

[0068] Step 15: If the fracturing effect does not meet the requirements, perform secondary fracturing.

[0069] Specifically, the fracturing effect can be judged by the amount of gas extracted and the weakening of the rock strata. If the expected fracturing effect is not met, secondary fracturing and other means can be adopted to increase the amount of gas extracted and further weaken the rock strata.

[0070] It is understood that, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of the different embodiments or examples.

[0071] The coal mine resource collaborative mining and mining-induced surrounding rock full-space damage control method provided in this invention involves large-scale hydraulic fracturing of the overburden before mining, modifying the permeability and strength of the strata and coal seam. The fracturing boreholes are constructed within the low-lying, thick, and hard basic roof strata, where the high strength and stability of the strata significantly reduce the risk of borehole collapse during gas drainage, improve gas release efficiency, reduce gas pressure, effectively prevent outburst risks during coal seam exposure, and reduce gas emission during coal seam excavation. Fracturing creates numerous cracks in the roof strata, significantly weakening the strength and integrity of the strata. Under the stress of mining support, the fracturing strata can be further broken up. After coal seam extraction, it will collapse and accumulate randomly in the goaf, effectively reducing the overburden length and utilizing the fully broken and randomly accumulated strata to support the overburden and promote goaf stress recovery. Furthermore, while reducing support stress, minimizing surrounding rock damage in the mining space, and preventing dynamic disasters, it also reduces the height of overburden damage and the depth of floor damage, and reduces the amount of water flowing into the roof and floor. It can efficiently and economically achieve coal mine gas extraction and control of damage to the roof, floor, and surrounding rock in the mining space.

[0072] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for coordinated mining of coal resources and full-space control of surrounding rock damage during mining, characterized in that, Includes the following steps: Based on the structural parameters of the coal seam roof, the stratigraphic position of the low-lying, thick, hard basic roof strata is determined. Based on the stratigraphic position of the aforementioned low-lying, thick, and hard underlying rock layer, the location and parameters of the fracturing boreholes are determined. The horizontal section of the fracturing borehole is located within the low-lying, thick, hard, basic top rock layer and covers the entire length of the mining face in terms of its strike. Fracturing operations are performed in the horizontal section to form fracturing fractures, and the development of the fracturing fractures is controlled so that the fracturing fractures penetrate the coal seam vertically. After the fracturing operation is completed, gas is extracted through the fracturing borehole; The fracturing borehole is an "L-shaped" borehole on the ground; The fracturing borehole includes a vertical section perpendicular to the low-lying thick and hard base rock layer, a horizontal section extending along the strike of the low-lying thick and hard base rock layer, and a sloping section for connecting the vertical section and the horizontal section. The determination of the layout and parameters of the fracturing boreholes includes: If it is determined that the horizontal section of a single fracturing borehole cannot control the entire length of the working face, two or more fracturing boreholes shall be arranged in the length direction of the working face; The determination of the layout and parameters of the fracturing boreholes includes: During fracturing, monitor the development of the fracturing fractures; The degree of fracturing, the effect of fracturing on the coal seam, and the horizontal distribution of the fracturing fractures are determined based on the development of the fracturing fractures. Based on the horizontal distribution of the fracturing fractures, the horizontal spacing between adjacent fracturing boreholes is determined so that the fracturing fractures can cover the entire mining area; The structural parameters of the coal seam roof include: the thickness of each stratum and the rock mechanical properties; Determining the stratigraphic position of the low-lying, thick, hard, basic top rock layer includes: Based on the thickness of each stratum and the mechanical properties of the rock, the key layer theory was used to conduct structural analysis of each stratum in the top plate to determine the strata of the low-lying, thick, and hard basic top stratum.

2. The method for coordinated mining of coal resources and full-space damage control of surrounding rock during mining, as described in claim 1, is characterized in that... If it is determined that the horizontal section of a single fracturing borehole cannot control the entire working face length, two fracturing boreholes are arranged in the working face length direction, with the two fracturing boreholes being constructed on the cut-in side and the stop-mining line side, respectively.

3. The method for coordinated mining of coal resources and full-space destruction control of surrounding rock during mining, as described in claim 1, is characterized in that... Fracturing operations are performed in the horizontal section to create fracturing fractures, including: Hydraulic fracturing operations are carried out in the horizontal section of the fracturing borehole, and hydraulic fracturing is performed in sections on the low-lying thick and hard basic top rock layer to form a hydraulic fracture network.

4. The method for coordinated mining of coal resources and full-space damage control of surrounding rock during mining, as described in claim 1, is characterized in that... If the fracturing effect is not satisfactory, secondary fracturing should be performed.

5. The method for coordinated mining of coal resources and full-space damage control of surrounding rock during mining, as described in claim 1, is characterized in that... The development of the fracturing fractures is controlled by adjusting the viscosity of the fracturing fluid, the pump pressure and flow rate of the fracturing pump, and by temporary plugging.

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