Collaborative mining and mining surrounding rock total-space damage control method for coal mine resources

Abstract

The invention relates to the technical field of coal mining, and provides a coal mine resource collaborative mining and mining surrounding rock total-space damage control method which comprises the following steps: determining the position of a low-position thick and hard basic roof rock layer on the basis of structural parameters of a coal seam roof; based on the layer position of the low-position thick and hard basic roof rock layer, the arrangement position and parameters of fracturing drill holes are determined; fracturing drilling construction is conducted, and the horizontal section of a fracturing drill hole is located in the low-position thick and hard basic roof stratum and covers the length of the whole stope face in the trend; performing fracturing construction on the horizontal section to form a fracturing crack, and controlling the development of the fracturing crack to enable the fracturing crack to penetrate through the coal seam in the vertical direction; and after fracturing construction is completed, gas is extracted through the fracturing drill holes. By means of the arrangement, coal seam gas resource recovery, gas disaster control, coal mine roof / floor water disaster prevention and control and mining space surrounding rock control can be achieved at the same time through roof low-position thick and hard basic roof rock stratum fracturing, the disaster prevention and control project amount is greatly reduced, the project cost is reduced, and the construction period is shortened.

Description

Technical Field

[0001] The invention relates to the technical field of coal mining, and in particular to a method for coordinated mining of coal resources and full-space destruction control of mining-induced surrounding rocks. Background Art

[0002] After coal seam mining, the original equilibrium state of the stratum will be broken. Under the action of mining stress concentration and unloading, the roof, floor and surrounding rock of the coal seam will suffer a series of damages. The destruction of the roof rock layer and the connection to the aquifer will induce water damage to the mine roof and the loss of water resources in the roof. The destruction of the floor rock layer and the connection to the aquifer will induce water damage to the floor. The stress concentration of the surrounding rock in the mining space will induce the destruction of the tunnel, and the dynamic load and strong mine pressure in the mining space will appear. At the same time, a large amount of methane is often produced during the coal metamorphosis and stored in the coal seam. During the coal seam mining process, gas will be released into the mining space, which is easy to cause gas accumulation and induce gas explosion. When the coal seam gas content is high and the pressure is too high, coal and gas outbursts may even occur. Coal seam gas can be used as a clean energy when fully utilized, but if it is discharged disorderly, its greenhouse effect is about twenty times that of carbon dioxide.

[0003] At present, the methods for coal seam gas resource recovery and disaster prevention and control mainly include pre-mining coal seam drilling extraction, coal seam hydraulic fracturing extraction, coal seam drilling water jet extraction and other methods. The prevention and control of coal mine roof water hazards and water resource protection mainly include pre-mining drainage, partial mining, backfill mining and other overburden damage control methods, channel grouting plugging, aquifer grouting modification and other methods. The prevention and control of floor water hazards mainly adopts floor regional and local grouting reinforcement, floor water release and other methods. The large-scale destruction of the surrounding rock and dynamic disasters of the mining space induced by stress concentration and large-scale instability in the mining space are mainly prevented and controlled by strengthening support, unloading pressure by drilling holes in the tunnel, unloading pressure by hydraulic fracturing of the roof rock layer, and reasonable arrangement of the mining space.

[0004] However, there is still a lack of comprehensive, efficient, proactive and economical means to address the surrounding rock damage problems and symbiotic gas resource recovery caused by the above-mentioned series of coal mining. Summary of the invention

[0005] The present invention provides a method for coordinated mining of coal mine resources and control of destruction of surrounding rocks in the entire space caused by mining, which is used to solve the problem that it is difficult to economically and efficiently realize gas development and utilization and disaster prevention and control in the prior art. It can efficiently and economically realize coal mine gas extraction and control of destruction of roof and floor plates and surrounding rocks in the mining space.

[0006] The present invention provides a method for coordinated mining of coal resources and full-space damage control of surrounding rocks caused by mining, comprising the following steps: Based on the structural parameters of the coal seam roof, determine the position of the low-lying thick and hard basic top rock layer; Determining the layout and parameters of the fracturing drilling holes based on the position of the low-lying thick and hard basic top rock layer; Performing fracturing drilling construction, wherein the horizontal section of the fracturing drilling is located in the low-lying thick and hard basic top rock layer and covers the entire length of the mining working face in the strike direction; Performing fracturing construction in the horizontal section to form a fracturing crack, and controlling the development of the fracturing crack so that the fracturing crack penetrates the coal seam vertically; After the fracturing construction is completed, gas is extracted through the fracturing boreholes.

[0007] According to a method for coordinated mining of coal resources and full-space damage control of mining surrounding rocks provided by the present invention, the fracturing borehole is an "L-shaped" borehole on the ground; The fracturing borehole includes a vertical section perpendicular to the low-level thick and hard basic top rock layer, the horizontal section extending along the direction of the low-level thick and hard basic top rock layer, and a deflection section for connecting the vertical section and the horizontal section.

[0008] According to a method for coordinated mining of coal resources and full-space damage control of mining surrounding rocks provided by the present invention, the determination of the layout position and parameters of the fracturing drilling holes includes: When 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 are arranged in the length direction of the working face.

[0009] According to a method for coordinated mining of coal mine resources and full-space destruction control of surrounding rock caused by mining provided by the present invention, when it is determined that the horizontal section of a single fracturing borehole cannot control the entire length of the working face, two fracturing boreholes are arranged in the length direction of the working face, and the two fracturing boreholes are constructed on the cutting eye side and the stop mining line side, respectively.

[0010] According to a method for coordinated mining of coal resources and full-space damage control of mining surrounding rocks provided by the present invention, the determination of the layout position and parameters of the fracturing drilling holes includes: monitoring the development of the fracturing cracks during fracturing; Based on the development of the hydraulic fractures, judging the degree of hydraulic fractures, the effect of hydraulic fractures on the coal seam and the horizontal distribution of the hydraulic fractures; Based on the horizontal distribution of the hydraulic fracturing cracks, the horizontal spacing between adjacent hydraulic fracturing boreholes is determined so that the hydraulic fracturing cracks can cover the entire mining area.

[0011] According to a method for coordinated mining of coal resources and full-space damage control of mining surrounding rocks provided by the present invention, the structural parameters of the coal seam roof include: thickness of rock layers at each level and rock mechanical properties.

[0012] According to a method for coordinated mining of coal resources and full-space damage control of mining surrounding rocks provided by the present invention, the determination of the position of the low-lying thick and hard basic top rock layer comprises: Based on the thickness of each stratum and the mechanical properties of rock, the key layer theory is used to analyze the structure of each stratum in the roof and determine the position of the low-lying thick and hard basic roof stratum.

[0013] According to a method for coordinated mining of coal resources and full-space damage control of surrounding rocks caused by mining provided by the present invention, fracturing construction is performed in the horizontal section to form fracturing cracks, comprising: Hydraulic fracturing operations are carried out in the horizontal section of the fracturing borehole, and hydraulic fracturing operations are carried out on the low-lying thick and hard basic top rock layer in sections to form a hydraulic fracture network.

[0014] According to a method for coordinated mining of coal resources and full-space damage control of mining surrounding rocks provided by the present invention, when it is determined that the fracturing effect does not meet the requirements, secondary fracturing is performed.

[0015] According to a method for coordinated mining of coal resources and full-space destruction control of surrounding rocks caused by mining provided by the present invention, the development of the fracturing cracks is controlled by adjusting the viscosity of the fracturing fluid, the pump pressure and displacement of the fracturing pump, and temporary plugging.

[0016] The method for coordinated mining of coal resources and control of the destruction of surrounding rocks in the whole space provided by the present invention is to perform large-scale hydraulic fracturing on the overburden before mining, transform the permeability of the rock layer and the coal seam and the overburden strength, and construct the fracturing drilling inside the low-position thick and hard basic top rock layer. The rock layer has high strength and good stability, which greatly reduces the risk of hole collapse during gas extraction, improves gas release efficiency, reduces gas pressure, effectively prevents and controls the risk of outburst when uncovering coal, and reduces the amount of gas gushing during coal seam mining. Fracturing creates a large number of cracks in the top rock layer, which greatly weakens the strength and integrity of the rock layer. The fracturing rock layer can be further broken under the action of mining support stress. After the coal seam is mined, it will collapse and pile up in the goaf area in a disorderly manner as it collapses. It can effectively reduce the hanging length of the top rock layer, and use the fully broken and disorderly piled rock layer to support the overburden layer and promote the recovery of goaf stress. In addition, it can reduce the height of overburden damage and the depth of bottom plate damage while achieving the goal of reducing support stress, reducing the destruction of surrounding rocks in the mining space and preventing and controlling dynamic disasters, and reducing the amount of water gushing from the top and bottom plates. This enables efficient and economical coal mine gas extraction and control of roof, floor and surrounding rock damage in the mining space. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 It is a schematic diagram of the stress concentration distribution of the overburden structure and the surrounding rock failure characteristics caused by mining.

[0019] Figure 2 It is a flow chart of a method for coordinated mining of coal mine resources and full-space destruction control of mining surrounding rocks provided by an embodiment of the present invention.

[0020] Figure 3 It is a schematic diagram of fracturing a thick and hard basic top rock formation provided by an embodiment of the present invention.

[0021] Figure 4 Schematic diagram of controlling the destruction of surrounding rocks in all spaces by means of a fracturing structure for thick hard overburden strata provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] In order to better understand the method for coordinated mining of coal resources and full-space damage control of mining surrounding rocks provided by the embodiment of the present invention, its application background is first introduced. After coal seam mining, the original equilibrium state of the stratum will be broken. Under the action of mining stress concentration and unloading, a series of damages will occur to the roof, floor and surrounding rocks of the coal seam, thereby inducing disasters such as roof water damage, floor water damage, and tunnel damage. At the same time, the gas in the coal seam is prone to induce gas explosion. When the gas content of the coal seam is high and the pressure is too high, it may even cause coal and gas outburst problems (for example, Figure 1 as shown).

[0024] Among the related technologies, coal seam gas resource recovery and disaster prevention methods mainly adopt methods such as pre-mining coal seam drilling extraction, coal seam hydraulic fracturing extraction, and coal seam drilling water jet extraction. Coal mine roof water hazard prevention and control and water resource protection mainly adopt pre-mining drainage, partial mining, backfill mining and other overburden damage control methods, channel grouting plugging, aquifer grouting modification and other methods. Floor water hazard prevention and control mainly adopts floor regional and local grouting reinforcement, floor water release and other methods. The large-scale destruction of the surrounding rock and dynamic disasters of the mining space induced by stress concentration and large-scale instability in the mining space are mainly prevented and controlled by strengthening support, unloading pressure by drilling holes in the tunnels, unloading pressure by hydraulic fracturing of the roof rock layer, and reasonable arrangement of the mining space.

[0025] Among the above-mentioned related technologies, gas development and utilization and disaster management methods are mainly carried out in coal seams, but coal seams often have strong plasticity, especially under high gas pressure and high ground stress conditions, the boreholes in the coal seams are very prone to collapse, and the water pressure cracks in the coal seams are also very easy to fail under the action of stress and coal powder blockage, making it difficult to achieve efficient gas extraction and efficient prevention and control of gas disasters.

[0026] In the roof water hazard prevention and control methods, water drainage often leads to excessive drainage and causes water resource loss. Existing low-loss mining methods such as limited thickness mining, strip mining, and backfill mining are often costly, affect production and reduce the recovery rate.

[0027] Among the existing methods for preventing and controlling water hazards in coal mine floors, the cost of regional grouting treatment is high and there are often blind spots in the treatment, making it difficult to achieve treatment effects.

[0028] Among the existing methods for controlling mining space destruction and dynamic disasters, local enhanced support and drilling pressure relief are often difficult to achieve effective results, roof hydraulic fracturing pressure relief is often relatively blind, and reasonable layout of mining space often cannot fully achieve the expected results.

[0029] Therefore, there is still a lack of comprehensive, efficient, proactive and economical means to address the surrounding rock damage problems and symbiotic gas resource recovery caused by the above-mentioned series of coal mining.

[0030] In response to the above technical problems, an embodiment of the present invention provides a method for coordinated mining of coal mine resources and full-space damage control of mining surrounding rocks, which can efficiently and economically achieve coal mine gas extraction and roof and floor plate as well as surrounding rock damage control in the mining space.

[0031] Combine the following Figure 2-Figure 4 The invention describes the method for coordinated mining of coal resources and full-space destruction control of mining surrounding rocks.

[0032] Figure 1 Schematic diagram of the process of the method for coordinated mining of coal resources and full-space damage control of surrounding rock caused by mining provided by an embodiment of the present invention, such as Figure 1 As shown, the method comprises the following steps: Step 10: Based on the structural parameters of the coal seam roof, determine the position of the low-lying thick and hard basic top rock layer.

[0033] Specifically, the structural parameters of the coal seam roof include the thickness of each stratum and the mechanical characteristics of the rock. The thickness of each stratum and the mechanical characteristics of the rock are statistically analyzed based on the drill column chart of the mine mining area. The key layer theory is used to deduce the distribution of the key overburden layer, thereby determining the position of the low-level thick and hard basic roof rock layer.

[0034] Step 11: Based on the position of the low-lying thick and hard basic top rock layer, determine the layout position and parameters of the fracturing drilling holes.

[0035] Specifically, after determining the position of the low-level thick and hard basic top rock layer, the layout position and parameters of the fracturing borehole are designed. The fracturing borehole is an "L-shaped" borehole constructed on the ground, that is, the fracturing borehole position, that is, the parameters are designed at the ground position corresponding to the coal mining working face. The fracturing borehole includes a vertical section perpendicular to the low-level thick and hard basic top rock layer, a horizontal section extending along the direction of the low-level thick and hard basic top rock layer, and an inclined section for connecting the above-mentioned vertical section and the above-mentioned horizontal section. Parameters such as the depth of the vertical section of the fracturing borehole, the length of the horizontal section, and the turning radius of the inclined section need to be designed in combination with the actual geological conditions, and are not specifically limited in the embodiments of the present invention.

[0036] It should be pointed out that the construction of "L-shaped" drilling is a mature existing technology. Therefore, the equipment and specific construction method used in the "L-shaped" drilling construction are not described in detail in the embodiments of the present invention.

[0037] Step 12: Perform fracturing drilling construction. The horizontal section of the fracturing drilling is located in the low-lying thick and hard basic top rock layer and covers the entire length of the mining working face in the strike direction.

[0038] Step 13: After the fracturing drilling construction is completed, fracturing construction is carried out in the horizontal section to form fracturing cracks, and the development of the fracturing cracks is controlled so that the fracturing cracks penetrate the coal seam vertically.

[0039] Specifically, hydraulic fracturing operations are carried out in the horizontal section of the fracturing borehole, and hydraulic fracturing construction is carried out in sections on the low-lying thick and hard basic top 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 displacement of the fracturing pump, temporary plugging, etc., so that the fracturing fractures can vertically penetrate the coal seam and fully pre-crack and weaken the low-lying thick and hard basic top rock layer.

[0040] Step 14: After the fracturing construction is completed, gas is extracted through the fracturing borehole. After the fracturing construction is completed, negative pressure is applied to the fracturing borehole to continuously extract coal seam gas.

[0041] Specifically, refer to Figure 3 and Figure 4 After the fracturing drilling construction is completed, fracturing construction is carried out in the horizontal section of the fracturing drilling hole. The fracturing cracks enter the coal seam and form complex cracks in the roof rock layer. The fracturing cracks can fully increase the permeability of the coal rock and reduce the structural integrity and overall strength of the roof rock layer. After the fracturing construction is completed, gas extraction is carried out through the "L-shaped" fracturing drilling hole. Since the fracturing drilling hole is located inside the low-lying thick and hard basic roof rock layer, the rock layer has high strength and good stability, which greatly reduces the risk of hole collapse during gas extraction, improves gas release efficiency, reduces gas pressure, effectively prevents and controls the risk of outbursts during coal uncovering, and reduces the amount of gas outbursts during coal seam mining. In addition, since the borehole is an "L-shaped" borehole on the ground, air will not be mixed in during gas extraction to reduce the gas concentration, which can effectively increase the extracted gas concentration and increase the utilization rate of extracted gas.

[0042] In addition, the fracturing process will create a large number of fracturing cracks in the rock mass. The cutting of the rock mass by the fracturing cracks and the interaction between the fracturing fluid and the rock mass will weaken the strength and integrity of the rock mass, so that the basic top rock layer, which originally showed periodic fracture movement after the coal seam was mined, is fully destroyed under the action of the mining support stress and collapses with mining. On the one hand, the collapse of the thick and hard basic top rock layer with mining can effectively reduce the hanging top of the top rock layer and reduce the stress concentration in the mining space caused by the self-central stress of the hanging top rock layer; on the other hand, the thick and hard basic top rock layer that collapses with mining will be randomly deposited in the goaf, and the coefficient of the randomly deposited rock mass will be significantly greater than that of the periodically broken neatly deposited rock mass. The randomly deposited rock mass is a typical strain hardening material, that is, when pressure acts on the randomly deposited rock mass, the bearing capacity of the randomly deposited rock mass will increase with the increase of load deformation. Therefore, the randomly deposited rock mass can provide certain support for the upper rock layer in time, reduce the subsidence of the overburden rock layer and weaken the risk of dynamic pressure caused by large-scale shear failure, while realizing the control of overburden damage and mining space pressure.

[0043] The reason why coal mining causes floor damage is that the mining stress is redistributed around the mining space to form a supporting stress, and a pressure relief zone is formed in the empty area after coal seam mining. The rock mass at the boundary of the mining space is shear-slipped under the huge stress difference between the pressurized area and the pressure relief area, and the hidden structure of the floor is unstable and damaged under the stress difference. Therefore, controlling the damage of the coal seam floor should start from reducing the size of the supporting stress and promoting the stress recovery of the empty area.

[0044] As mentioned above, after fracturing, the roof rock will collapse as mining progresses, the hanging distance will be greatly reduced, and the mining support stress will be effectively controlled. On the other hand, the roof rock that collapses as mining progresses can fill the goaf in time and promote the recovery of the rock stress in the goaf. Therefore, large-scale hydraulic fracturing of the roof rock can effectively reduce the boundary stress difference of the mining space and achieve the effect of controlling the damage to the coal seam floor.

[0045] Compared with related technologies, the method for coordinated mining of coal mine resources and full-space damage control of mining surrounding rock provided by the embodiment of the present invention can simultaneously achieve coal seam gas resource recovery, gas disaster control, coal mine roof / floor water hazard prevention and control, and mining space surrounding rock control by adopting low-position thick and hard basic top rock layer fracturing of the roof, thereby greatly reducing the amount of disaster prevention and control projects, reducing project costs and shortening the construction period.

[0046] In one embodiment of the present invention, step 11 includes: Step 110: When it is determined that the horizontal section of a single fracturing borehole cannot control the entire length of the working surface, two or more fracturing boreholes are arranged in the length direction of the working surface so that the fracturing boreholes can cover the entire working surface in the length direction and reduce blind spots.

[0047] 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 length of the working face, two fracturing boreholes can be arranged in the length direction of the working face, and the two fracturing boreholes are constructed on one side of the cutting line and the stop production line respectively.

[0048] In one embodiment of the present invention, step 11 further includes: Step 111: Detect the development of the fracturing cracks during fracturing.

[0049] Step 112: judging the degree of fracturing, the effect of fracturing on the coal seam and the horizontal distribution of the fracturing cracks based on the development of the fracturing cracks.

[0050] Step 113: Based on the horizontal distribution of the hydraulic fractures, the spacing between adjacent hydraulic fracture holes is determined so that the hydraulic fractures can cover the entire mining area.

[0051] Specifically, before coal mining, an "L-shaped" fracturing borehole is constructed on the ground. The horizontal landing point of the fracturing borehole is located in the low-lying thick and hard basic roof rock layer, and covers the entire length of the mining face in the axial direction. After the "L-shaped" borehole is constructed, hydraulic fracturing is carried out, and the fracturing parameters are adjusted to ensure that the fracturing gap can penetrate the coal seam while effectively reducing the integrity and overall strength of the roof rock layer. During fracturing, the development of the fracturing cracks is monitored to determine the degree of fracturing, the effect of fracturing on the coal seam, and the horizontal distribution of the fracturing cracks. The horizontal spacing of adjacent fracturing boreholes is then determined based on the horizontal distribution of the fracturing cracks. The fracturing cracks generated by adjacent fracturing boreholes should be connected to each other to form a continuous fracturing network to ensure that the fracturing cracks can cover the entire mining area in both vertical and horizontal directions, avoid blind spots, and avoid overlapping cracks and waste of resources. Reasonable borehole spacing design can ensure the effectiveness of fracturing operations while reducing unnecessary costs and environmental impacts.

[0052] In one embodiment of the present invention, the method for coordinated mining of coal resources and full-space damage control of surrounding rocks caused by mining further includes the following steps: Step 15: When it is determined that the fracturing effect does not meet the requirements, perform secondary fracturing.

[0053] Specifically, the fracturing effect can be judged by the gas extraction volume and the weakening of rock formation strength. If the expected fracturing effect is not met, secondary fracturing and other means can be adopted to increase the gas extraction volume and further weaken the rock formation strength.

[0054] It is to be understood that, without mutual contradiction, those skilled in the art may combine and combine the different embodiments or examples and the features of the different embodiments or examples described in this specification.

[0055] The method for coordinated mining of coal resources and full-space destruction control of mining surrounding rock provided by the embodiment of the present invention performs large-scale hydraulic fracturing on the overburden before mining to transform the permeability of the rock layer and coal seam and the overburden strength. The fracturing drilling is constructed inside the low-position thick and hard basic top rock layer, and the rock layer has high strength and good stability, so that the risk of hole collapse during gas extraction is greatly reduced, the gas release efficiency is improved, the gas pressure is reduced, the risk of outburst during coal uncovering is effectively prevented, and the amount of gas gushing during coal seam mining is reduced. Fracturing creates a large number of cracks in the top rock layer, which greatly weakens the strength and integrity of the rock layer. The fracturing rock layer can be further broken under the action of mining support stress. After the coal seam is mined, it will collapse and pile up in the goaf area in a disorderly manner as it collapses. It can effectively reduce the hanging length of the top rock layer, and use the fully broken and disorderly piled rock layer to support the overburden layer and promote the recovery of the goaf stress. In addition, it can reduce the overburden damage height and the bottom plate damage depth while achieving the goal of reducing the support stress, reducing the surrounding rock damage in the mining space and preventing and controlling dynamic disasters, and reducing the water gushing amount of the top and bottom plates. It can efficiently and economically realize coal mine gas extraction and control of roof, floor and surrounding rock damage in mining space.

[0056] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions 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 damage control of surrounding rocks caused by mining, characterized in that: The following steps are involved: Based on the structural parameters of the coal seam roof, determine the position of the low-lying thick and hard basic top rock layer; Determining the layout and parameters of the fracturing drilling holes based on the position of the low-lying thick and hard basic top rock layer; Performing fracturing drilling construction, wherein the horizontal section of the fracturing drilling is located in the low-lying thick and hard basic top rock layer and covers the entire length of the mining working face in the strike direction; Performing fracturing construction in the horizontal section to form a fracturing crack, and controlling the development of the fracturing crack so that the fracturing crack penetrates the coal seam vertically; After the fracturing construction is completed, gas is extracted through the fracturing boreholes.

2. The method for coordinated mining of coal resources and full-space damage control of surrounding rock caused by mining according to claim 1 is characterized in that: The fracturing borehole is an "L-shaped" borehole on the ground; The fracturing borehole includes a vertical section perpendicular to the low-level thick and hard basic top rock layer, the horizontal section extending along the direction of the low-level thick and hard basic top rock layer, and a deflection section for connecting the vertical section and the horizontal section.

3. The method for coordinated mining of coal resources and full-space damage control of surrounding rocks caused by mining according to claim 1 is characterized in that: The step of determining the arrangement position and parameters of the fracturing drilling holes includes: When 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 are arranged in the length direction of the working face.

4. The method for coordinated mining of coal resources and full-space damage control of mining surrounding rocks according to claim 3 is characterized in that: When it is determined that the horizontal section of a single fracturing borehole cannot control the entire length of the working face, two fracturing boreholes are arranged in the length direction of the working face, and the two fracturing boreholes are constructed on the cutting side and the stop production line side respectively.

5. The method for coordinated mining of coal resources and full-space damage control of surrounding rock caused by mining according to claim 3 is characterized in that: The step of determining the arrangement position and parameters of the fracturing drilling holes includes: monitoring the development of the fracturing cracks during fracturing; Based on the development of the hydraulic fractures, judging the degree of hydraulic fractures, the effect of hydraulic fractures on the coal seam and the horizontal distribution of the hydraulic fractures; Based on the horizontal distribution of the hydraulic fracturing cracks, the horizontal spacing between adjacent hydraulic fracturing boreholes is determined so that the hydraulic fracturing cracks can cover the entire mining area.

6. The method for coordinated mining of coal resources and full-space damage control of surrounding rock caused by mining according to any one of claims 1 to 5, characterized in that: The structural parameters of the coal seam roof include: the thickness of each stratum and the mechanical properties of the rock.

7. The method for coordinated mining of coal resources and full-space damage control of surrounding rock caused by mining according to claim 6 is characterized in that: Determining the position of the low-lying thick and hard basic top rock layer includes: Based on the thickness of each stratum and the mechanical properties of rock, the key layer theory is used to analyze the structure of each stratum in the roof and determine the position of the low-lying thick and hard basic roof stratum.

8. The method for coordinated mining of coal resources and full-space damage control of surrounding rock caused by mining according to claim 1 is characterized in that: Performing fracturing construction in the horizontal section to form fracturing cracks includes: Hydraulic fracturing operations are carried out in the horizontal section of the fracturing borehole, and hydraulic fracturing operations are carried out on the low-lying thick and hard basic top rock layer in sections to form a hydraulic fracture network.

9. The method for coordinated mining of coal resources and full-space damage control of surrounding rock caused by mining according to claim 1 is characterized in that: When it is determined that the fracturing effect does not meet the requirements, secondary fracturing is carried out.

10. The method for coordinated mining of coal resources and full-space damage control of mining surrounding rocks according to claim 1, characterized in that: The development of the fracturing cracks is controlled by adjusting the viscosity of the fracturing fluid, the pump pressure and displacement of the fracturing pump, and temporary plugging.

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