Coal seam mining overburden control method and device
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- TIANDI SCI & TECH CO LTD
- Filing Date
- 2022-12-20
- Publication Date
- 2026-07-21
Smart Images
Figure CN115898404B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of coal mining, and in particular to a method and apparatus for controlling overburden in coal seam mining. Background Technology
[0002] During large-scale coal mining, the roof strata of coal seams are prone to collapse or fracture, resulting in water-conducting fissures in a large area of strata above the roof, which damages the groundwater environment.
[0003] In related technologies, coal seam mining generally employs processes such as partial mining, limited-thickness mining, backfilling mining, and grouting to reduce sedimentation. However, these methods cannot control the extent of mining-induced damage during coal seam mining, which is detrimental to the normal mining and excavation continuity of the mine and results in significant resource waste, leading to a reduction in coal production efficiency. Summary of the Invention
[0004] This invention provides a method and apparatus for controlling overburden in coal seam mining, which solves the defects of existing technologies that cannot control the range of mining-induced damage during coal seam mining, resulting in serious resource waste and reduced coal production efficiency, and achieves controllable range of mining-induced damage during coal seam mining.
[0005] This invention provides a method for controlling overburden in coal seam mining, comprising:
[0006] Obtain the rock quality indicators of the coal seam roof, the thickness of the bedrock pillar, and the thickness of the coal seam;
[0007] Based on the rock quality indicators, the distribution information of the hard and thick rock layers is obtained, including the thickness and location of the hard and thick rock layers;
[0008] Based on the coal seam thickness and the preset fracture-to-mining ratio, the overburden failure height is obtained; the fracture-to-mining ratio includes at least one of the ratio of the maximum height of the caving zone to the mining thickness and the ratio of the maximum height of the fracture zone to the mining thickness.
[0009] If the ratio of the thickness of the hard, thick rock layer to the thickness of the coal seam is greater than or equal to a thickness threshold, the overburden failure height is less than or equal to the thickness of the bedrock pillar, and the location is a preset target location, then the hard, thick rock layer is determined to be a pre-fractureable hard, thick rock layer. The target location includes a distance A from the hard, thick rock layer to the caving zone. h The location and the distance B of the hard, thick rock layer from the collapse zone h At least one of the positions.
[0010] According to the present invention, a method for controlling overburden in coal seam mining is provided, wherein the hard, thick rock strata include hard, thick rock strata A and hard, thick rock strata B, and the distance from A... h The distance B is the distance between the hard, thick rock layer A and the coal seam. hThe distance between the hard, thick rock layer B and the coal seam is given. The fracture-to-mining ratio corresponding to the hard, thick rock layer A is the ratio of the maximum height of the overburden failure caving zone to the mining thickness, C0. The fracture-to-mining ratio corresponding to the hard, thick rock layer B is the ratio of the maximum height of the overburden failure fracture zone to the mining thickness, C1.
[0011] The determination that the ratio of the thickness of the hard, thick rock layer to the thickness of the coal seam is greater than or equal to a thickness threshold, the overburden failure height is less than or equal to the thickness of the bedrock pillar, and the location is a preset target location includes:
[0012] The distance B h Greater than or equal to 2M and less than or equal to MC0, where M represents the thickness of the coal seam;
[0013] The distance A h Greater than or equal to MC0, and less than or equal to 0.8M(C0+C1)-A m A m The thickness of the hard, thick rock layer A is given.
[0014] According to a method for controlling overburden in coal seam mining provided by the present invention, after determining that the hard, thick rock stratum is a hard, thick rock stratum capable of pre-fracture, the method further includes:
[0015] The pre-fractured hard and thick rock strata are subjected to pre-fracture treatment to obtain the target hard and thick rock strata;
[0016] If the ratio of the rock quality index in the target hard thick rock layer to the rock quality index of the pre-fractureable hard thick rock layer is less than the rock quality index threshold, the target hard thick rock layer is determined to be a modified hard thick rock layer.
[0017] According to a method for controlling overburden in coal seam mining provided by the present invention, the step of pre-fracture treatment of the pre-fractureable hard thick rock strata to obtain the target hard thick rock strata includes:
[0018] When the thickness of the hard rock layer is less than or equal to the hard rock layer thickness threshold, boreholes are drilled along multiple vertical centers of the hard rock layer to obtain the target hard rock layer.
[0019] Wherein, the distance between the boreholes on both sides of the hard thick rock stratum is greater than the dip width of the mining face, and the distance between the borehole on each side and the roadway of the working face is greater than or equal to the distance T, wherein the distance T is determined based on the distance between the target hard thick rock stratum and the coal seam.
[0020] According to a method for controlling overburden in coal seam mining provided by the present invention, the method of pre-fractured the pre-fractureable hard thick rock strata to obtain the target hard thick rock strata further includes:
[0021] When the thickness of the hard rock layer is greater than the hard rock layer thickness threshold, and the difference between the thickness of the hard rock layer and the hard rock layer thickness threshold exceeds the distance threshold, the number of borehole rows is determined based on the distance threshold and the difference.
[0022] Based on the number of borehole rows, boreholes are drilled along multiple vertical centers of the hard, thick rock layer to obtain the target hard, thick rock layer.
[0023] According to the present invention, a coal seam mining overburden control device is provided, the device comprising:
[0024] The acquisition module is used to acquire the rock quality indicators of the coal seam roof, the thickness of the bedrock pillar, and the thickness of the coal seam.
[0025] The hard and thick rock layer detection module is used to obtain the distribution information of the hard and thick rock layer based on the rock quality index. The distribution information of the hard and thick rock layer includes the thickness and location of the hard and thick rock layer.
[0026] The overburden failure range detection module is used to obtain the overburden failure height based on the coal seam thickness and a preset fracture-mining ratio; the fracture-mining ratio includes at least one of the ratio of the maximum height of the caving zone to the mining thickness and the ratio of the maximum height of the fracture zone to the mining thickness.
[0027] The pre-fractureable hard thick rock strata detection module is used to determine that the hard thick rock strata are pre-fractureable hard thick rock strata when the ratio of the thickness of the hard thick rock strata to the thickness of the coal seam is greater than or equal to a thickness threshold, the overburden failure height is less than or equal to the thickness of the bedrock pillar, and the location is a preset target location. The target location includes a distance A from the hard thick rock strata to the caving zone. h The location and the distance B of the hard, thick rock layer from the collapse zone h At least one of the positions.
[0028] According to the present invention, a coal seam mining overburden control device further includes:
[0029] The pre-splitting module is used to pre-splitting the hard and thick rock layer after determining that the hard and thick rock layer is a pre-splitting hard and thick rock layer, so as to obtain the target hard and thick rock layer.
[0030] The hard thick rock layer modification detection module is used to determine that the target hard thick rock layer is a modified hard thick rock layer when the ratio of the rock quality index in the target hard thick rock layer to the rock quality index of the pre-fractureable hard thick rock layer is less than the rock quality index threshold.
[0031] The present invention also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the coal seam mining overburden control method as described above.
[0032] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the coal seam mining overburden control method as described above.
[0033] The present invention also provides a computer program product, including a computer program that, when executed by a processor, implements the coal seam mining overburden control method as described above.
[0034] The coal seam mining overburden control and device provided by this invention obtains the rock quality indicators of the coal seam roof, the thickness of the bedrock pillar, and the coal seam thickness to predict the thickness of the hard and thick strata. It then uses the thickness of the hard and thick strata and the fracturing ratio to calculate the overburden failure height at the start of coal seam mining. Finally, when the thickness of the hard and thick strata, the overburden failure height, and the location of the hard and thick strata all meet preset conditions, the hard and thick strata are determined to be pre-fracturing hard and thick strata. This achieves controllable overburden failure during coal seam mining, provides a basis for judgment in the subsequent pre-fracturing process of the hard and thick strata, and thus improves the efficiency of coal seam mining. Attached Figure Description
[0035] 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.
[0036] Figure 1 This is a schematic flowchart of the coal seam mining overburden control method provided by the present invention;
[0037] Figure 2 This is one of the schematic diagrams of the distribution of coal seams and hard, thick rock strata provided by the present invention;
[0038] Figure 3 This is the second schematic diagram of the distribution of coal seams and hard, thick rock strata provided by the present invention;
[0039] Figure 4 This is a schematic diagram of the interface between the pre-splitting borehole and the pre-splitting segment provided by the present invention;
[0040] Figure 5 This is a schematic diagram of the interface of the pre-crack provided by the present invention;
[0041] Figure 6 This is a schematic diagram of the pre-splitting borehole distribution interface provided by the present invention;
[0042] Figure 7 This is a schematic diagram of the overburden control device for coal seam mining provided by the present invention;
[0043] Figure 8 This is a schematic diagram of the physical structure of an electronic device provided by the present invention. Detailed Implementation
[0044] 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.
[0045] The following is combined Figures 1-7 The present invention describes a method and apparatus for controlling overburden in coal seam mining.
[0046] Figure 1 This is one of the flowcharts illustrating the coal seam mining overburden control method provided by the present invention, such as... Figure 1 As shown, the present invention provides a method for controlling overburden in coal seam mining, comprising the following steps:
[0047] Step 110: Obtain the rock quality indicators of the coal seam roof, the thickness of the bedrock pillar, and the coal seam thickness.
[0048] In this step, rock quality indicators include RQD (Rock Quality Designation) and uniaxial compressive strength, etc.
[0049] In this embodiment, the overburden structure of the coal seam roof is analyzed. By calculating the content of sandstone and mudstone in the coal seam roof and analyzing the uniaxial compressive strength of sandstone and mudstone, the hard and thick rock layers in the overburden are identified. For example, rock layers with a uniaxial compressive strength greater than 40 MPa and a rock quality index RQD ≥ 70% are hard and thick rock layers.
[0050] Figure 2 This is one of the schematic diagrams of the distribution of coal seams and hard, thick rock strata provided by the present invention. Figure 2 In the embodiment shown, the coal seam thickness is M, and there are two hard, thick rock layers in the overburden, namely hard, thick rock layer A and hard, thick rock layer B. The thickness of hard, thick rock layer A is A. m The bottom boundary of the hard, thick rock layer A is A's distance from the coal seam. h The thickness of the hard, thick rock layer B is B. m The bottom boundary of the hard, thick rock layer B is B' from the coal seam. h The thickness of the bedrock column is the distance from the upper part of the coal seam to the bottom boundary of the loose layer.
[0051] Step 120: Based on rock quality indicators, obtain the distribution information of hard and thick rock layers, including the thickness and location of the hard and thick rock layers.
[0052] In this step, the uniaxial compressive strength and RQD value of the rock in the coal seam roof can be detected to determine whether the rock belongs to a hard and thick rock layer, and then the location and thickness of the hard and thick rock layer in the coal seam roof can be detected.
[0053] In this embodiment, the hard, thick rock strata in the coal seam roof can be a single layer or multiple layers.
[0054] Figure 3 This is the second schematic diagram of the distribution of coal seams and hard, thick rock strata provided by the present invention. Figure 3 In the embodiment described, there are two hard and thick rock layers in the roof of the coal seam. Hard and thick rock layer A is located in the upper middle region of the fracture zone, and hard and thick rock layer B is located in the upper part of the caving zone and the lower middle region of the fracture zone. The upper region of the fracture zone is a tortuous subsidence zone.
[0055] In this embodiment, the rock can be classified as a hard, thick rock layer if the rock's uniaxial compressive strength is greater than 40 MPa and the rock quality index RQD exceeds a preset value (e.g., 70%).
[0056] Step 130: Based on the coal seam thickness and the preset fracture-mining ratio, obtain the overburden failure height; the fracture-mining ratio includes at least one of the ratio of the maximum height of the caving zone to the mining thickness and the ratio of the maximum height of the fracture zone to the mining thickness.
[0057] In this step, the fracture-to-mining ratio can be the ratio of the maximum height of the overburden fracture zone to the mining thickness, the ratio of the maximum height of the overburden fracture zone to the mining thickness, or the ratio of the maximum height of the combined fracture zone to the mining thickness.
[0058] In this embodiment, the overburden failure height during coal seam mining in this area can be expressed by the following formula:
[0059] D = MC;
[0060] Where D represents the overburden failure height, M represents the coal seam thickness, and C represents the ratio of the maximum height of the overburden failure caving zone and fracture zone to the mining thickness, i.e., the fracture-to-mining ratio; the unit of each parameter can be m.
[0061] exist Figure 3 In the embodiment shown, the overburden failure height D is composed of the caving zone height MC0 and the fracture zone height MC1.
[0062] Step 140: If the ratio of the thickness of the hard, thick rock layer to the thickness of the coal seam is greater than or equal to the thickness threshold, the overburden failure height is less than or equal to the thickness of the bedrock pillar, and the location is the target location, then the hard, thick rock layer is determined to be a pre-fractureable hard, thick rock layer. The target location includes the distance A between the hard, thick rock layer and the caving zone. hLocation and distance of the thick, hard rock layer from the collapse zone B h At least one of the positions.
[0063] In this step, the thickness threshold can be customized according to the user's actual needs. For example, for coal seam mining areas with different terrains, the thickness threshold can be 5. Then, when the coal seam thickness is 3m, the thickness of a single hard rock layer should be at least 15m. Similarly, if the coal seam mining thickness is 5m, the thickness of a single hard rock layer in the overburden should not be less than 25m. At this time, it is considered that the thickness of the hard rock layer has the conditions to modify and weaken it to achieve control of mining impact.
[0064] It should be noted that the height of overburden failure varies depending on the degree of rock strata collapse and fracturing. The area directly located on the top of the coal seam, which collapses violently and loses its original stratification, is called the caving zone. The area of rock strata above the caving zone that has fractured but has not lost its original stratification is called the fracture zone.
[0065] In this embodiment, when the ratio of the thickness of the hard, thick rock layer to the thickness of the coal seam is greater than or equal to a thickness threshold, and the thickness of the bedrock pillar on the roof of the coal seam is J... m When the overburden failure height is greater than the hard, thick rock layer located in the fracture zone and at a certain distance from the collapse zone, it indicates that the overburden structure modification effect is good and mining impact control is easy to achieve.
[0066] In this embodiment, if multiple layers of hard, thick rock strata exist simultaneously in the roof of the coal seam, a higher level of mining impact control can be achieved through multiple overburden structure modifications.
[0067] In this embodiment, if the hard, thick rock layer is located above or near the top boundary of the fracture zone, it is not conducive to controlling the impact of mining.
[0068] The overburden control method for coal seam mining provided in this invention obtains the rock quality indicators of the coal seam roof, the thickness of the bedrock pillar, and the coal seam thickness to predict the thickness of the hard and thick strata. It then uses the thickness of the hard and thick strata and the fracturing ratio to calculate the overburden failure height at the start of coal seam mining. Finally, when the thickness of the hard and thick strata, the overburden failure height, and the location of the hard and thick strata all meet preset conditions, the hard and thick strata are determined to be pre-fracturingable. This achieves controllable overburden failure during coal seam mining, provides a basis for judgment in the subsequent pre-fracturing process of the hard and thick strata, and thus improves coal seam mining efficiency.
[0069] In some embodiments, the hard, thick rock layer includes hard, thick rock layer A and hard, thick rock layer B, at a distance from A. h The distance between the hard, thick rock layer A and the coal seam is [distance B]. hThe distance between the thick hard rock layer B and the coal seam is given. The fracture-to-mining ratio corresponding to the thick hard rock layer A is the ratio of the maximum height of the overburden failure caving zone to the mining thickness (C0). The fracture-to-mining ratio corresponding to the thick hard rock layer B is the ratio of the maximum height of the overburden failure fracture zone to the mining thickness (C1). The target location is determined when the ratio of the thickness of the thick hard rock layer to the thickness of the coal seam is greater than or equal to a thickness threshold, the overburden failure height is less than or equal to the bedrock pillar thickness, and the location is a preset target location. This includes the distance B between the thick hard rock layer B and the coal seam. h Greater than or equal to 2M and less than or equal to MC0, where M represents the coal seam thickness; the distance A between the hard, thick rock layer A and the coal seam. h Greater than or equal to MC0, and less than or equal to 0.8M(C0+C1)-A m A m The thickness of the hard, thick rock layer A is given.
[0070] In this embodiment, both a hard, thick rock layer A and a hard, thick rock layer B exist simultaneously in the roof of the coal seam. The hard, thick rock layer B is located below the hard, thick rock layer A. Therefore, based on the distance B between the hard, thick rock layer B and the coal seam... h The effect of overburden structure modification in the hard, thick rock layer B can be determined.
[0071] exist Figure 3 In the embodiment shown, the distance between the hard, thick rock layer B and the coal seam satisfies 2M≤B h When ≤MC0, the effect of overburden structure modification in hard and thick rock layer B is considered to be better; otherwise, the effect is poor.
[0072] In this embodiment, based on the distance A between the hard, thick rock layer A and the coal seam... h The effect of overburden structure modification in the hard, thick rock layer B can be determined.
[0073] exist Figure 3 In the embodiment shown, the distance A between the hard, thick rock layer A and the coal seam is... h When MC0≤A h And A h +A m When the concentration is ≤0.8MC, the modification effect on the overlying structure in the hard, thick rock layer A is considered to be better; A m The thickness of the hard, thick rock layer A is given.
[0074] The coal seam mining overburden control method provided in this embodiment of the invention determines the effect of overburden structure modification in the two hard-thickness layers by judging whether the position of each hard-thickness layer in the fracture zone is subject to preset conditions when there are two hard-thickness layers in the coal seam roof, thereby improving the reliability of the evaluation of the feasibility of controlling mining impact.
[0075] In some embodiments, after determining that the hard thick rock layer is a pre-fractureable hard thick rock layer, the method further includes: performing pre-fracture treatment on the pre-fractureable hard thick rock layer to obtain a target hard thick rock layer; and determining that the target hard thick rock layer is a modified hard thick rock layer when the ratio of the rock quality index in the target hard thick rock layer to the rock quality index in the pre-fractureable hard thick rock layer is less than the rock quality index threshold.
[0076] In this embodiment, the rock quality index threshold can be set according to user needs; for example, the rock quality index threshold is 0.6.
[0077] In this embodiment, after identifying the hard, thick rock strata that can be pre-fractured, the hard, thick rock strata can be pre-fractured by high-pressure hydraulic fracturing to change their original stratum integrity and strength, and weaken their mechanical properties.
[0078] In this embodiment, taking the thick rock layer A as an example, the pre-splitting treatment steps of the overlying rock structure are as follows: (1) First, a pre-splitting borehole is constructed in the middle of the thick rock layer A; (2) High-pressure hydraulic fracturing is carried out in the borehole to generate a network of cracks in the thick rock layer A; (3) Core sampling is performed to detect the development of the crack network and the integrity of the rock mass in the thick rock layer A after the pre-splitting modification treatment.
[0079] In this embodiment, the RQD of the hard, thick rock layer before drilling is 0.8, and the RQD of the hard, thick rock layer after drilling is 0.4. Since the ratio of 0.4 to 0.8 is less than 0.6, the pre-fracture process of the target hard, thick rock layer is considered to be qualified.
[0080] In this embodiment, if the pre-cracking process is unqualified, supplementary pre-cracking is required.
[0081] Figure 4 This is a schematic diagram of the interface between the pre-splitting borehole and the pre-splitting segment provided by the present invention. Figure 4 In the embodiment shown, I-IX pre-splitting segments are set in the middle of the hard and thick rock layer A, and each pre-splitting segment is drilled once.
[0082] Figure 5 This is a schematic diagram of the interface of the pre-crack provided by the present invention. Figure 5 In the embodiment shown, after drilling multiple pre-splitting segments in the middle of the hard and thick rock layer A, the location of each drill hole corresponds to a set of artificial pre-splitting cracks.
[0083] The coal seam mining overburden control method provided in this invention pre-fracturing the hard and thick rock strata through high-pressure hydraulic fracturing, avoids pollution to the groundwater environment, takes into account both environmental protection and coal seam mining cost constraints, and improves the environmental protection during coal seam mining.
[0084] In some embodiments, pre-fracture treatment is performed on a pre-fractureable hard thick rock stratum to obtain a target hard thick rock stratum, including: drilling holes along multiple vertical centers of the hard thick rock stratum when the thickness of the hard thick rock stratum is less than or equal to a hard rock stratum thickness threshold to obtain the target hard thick rock stratum; wherein the distance between the holes on both sides of the hard thick rock stratum is greater than the dip width of the longwall face, and the distance between the hole on each side and the longwall face roadway is greater than or equal to distance T, where distance T is determined based on the distance between the target hard thick rock stratum and the coal seam.
[0085] In this embodiment, different hard rock layer thickness thresholds can be set according to different formation hardness or primary fracture development. The hard rock layer thickness threshold can be set according to user needs, for example, the hard rock layer thickness threshold is 20m.
[0086] In this embodiment, the distance T can be set according to user needs. For example, the hard rock layer thickness threshold can be between 20m and 50m.
[0087] In this embodiment, the working face roadway is located on both sides of the longwall face.
[0088] In this embodiment, the distance T can be determined by the following formula:
[0089] T = A h / tan70°+10;
[0090] Among them, A h This indicates the distance between the hard, thick rock layer A and the coal seam.
[0091] Figure 6 This is a schematic diagram of the pre-splitting borehole distribution interface provided by the present invention. Figure 6 In the embodiment shown, eight boreholes are drilled along the vertical centers of the hard, thick rock layer A in the middle, resulting in eight boreholes. The distance L between two adjacent boreholes is less than the distance between the first and eighth boreholes. The distance between the first borehole and the left edge of the working face roadway a is greater than the distance T, and the distance between the eighth borehole and the right edge of the working face roadway b is greater than the distance T.
[0092] The coal seam mining overburden control method provided in this embodiment of the invention, by drilling holes along multiple vertical centers of the hard rock layer when the thickness of the hard rock layer is less than or equal to the hard rock layer thickness threshold, and the distance between the holes on both sides of the hard rock layer is greater than the dip width of the mining face, and by setting the distance between the holes on each side of the hard rock layer and the working face roadway to be greater than the distance T, can ensure the development of fracture network and rock mass integrity in the hard rock layer, and further improve the modification effect of the hard rock layer.
[0093] In some embodiments, pre-fracture treatment is performed on the pre-fractureable hard thick rock layer to obtain the target hard thick rock layer, which further includes: when the thickness of the hard thick rock layer is greater than the hard rock layer thickness threshold, and the difference between the thickness of the hard thick rock layer and the hard rock layer thickness threshold exceeds the distance threshold, determining the number of borehole rows based on the distance threshold and the difference; and drilling along multiple vertical centers of the hard thick rock layer based on the number of borehole rows to obtain the target hard thick rock layer.
[0094] In this embodiment, the distance threshold can be set according to user needs; for example, the distance threshold can be 10m.
[0095] In this embodiment, the number of pre-drilled holes is determined based on the thickness of the hard rock layer. When the thickness of the hard rock layer exceeds the hard rock layer thickness threshold, drilling is only performed in the middle of the hard rock layer, which cannot guarantee the development of the fracture network and the integrity of the rock mass in the hard rock layer.
[0096] In this embodiment, the hard rock layer thickness threshold is 20m, and when the thickness A of the hard rock layer is... m For thicknesses greater than 20m, an additional row of boreholes is added for every 10m increase in thickness; for example, A m When the depth is 43m, the number of borehole rows is 3.
[0097] In some embodiments, when there is only one hard, thick rock layer within the overburden failure height, the drilling density and the number of pre-splitting segments can be increased to carry out deeper pre-splitting construction.
[0098] The coal seam mining overburden control device provided by the present invention is described below. The coal seam mining overburden control device described below can be referred to in correspondence with the coal seam mining overburden control method described above.
[0099] The coal seam mining overburden control method provided in this invention, by reasonably adjusting the number of boreholes in the thick hard rock layer when the thickness of the thick hard rock layer is greater than the hard rock layer thickness threshold, can ensure the development of fracture network and the integrity of rock mass in the thick hard rock layer.
[0100] Figure 7 This is a schematic diagram of the overburden control device for coal seam mining provided by the present invention, as shown below. Figure 7 As shown, the coal seam mining overburden control device includes an acquisition module 710, a hard and thick rock layer detection module 720, a hard and thick rock layer detection module 730, and an overburden damage range detection module 740.
[0101] The acquisition module 710 is used to acquire the rock quality indicators of the coal seam roof, the thickness of the bedrock pillar, and the thickness of the coal seam.
[0102] The hard and thick rock layer detection module 720 is used to obtain the distribution information of hard and thick rock layers based on rock quality indicators. The distribution information of hard and thick rock layers includes the thickness and location of the hard and thick rock layers.
[0103] The overburden failure range detection module 730 is used to obtain the overburden failure height based on the coal seam thickness and a preset fracture-mining ratio; the fracture-mining ratio includes at least one of the ratio of the maximum height of the caving zone to the mining thickness and the ratio of the maximum height of the fracture zone to the mining thickness.
[0104] The pre-fractureable hard thick rock strata detection module 740 is used to determine whether a hard thick rock strata is a pre-fractureable hard thick rock strata when the ratio of the thickness of the hard thick rock strata to the thickness of the coal seam is greater than or equal to a thickness threshold, the overburden failure height is less than or equal to the thickness of the bedrock pillar, and the location is a target location. The target location includes the distance A between the hard thick rock strata and the caving zone. h Location and distance of the thick, hard rock layer from the collapse zone B h At least one of the positions.
[0105] The coal seam mining overburden control device provided in this embodiment of the invention obtains the rock quality indicators of the coal seam roof, the thickness of the bedrock pillar, and the coal seam thickness to predict the thickness of the hard and thick strata. It then uses the thickness of the hard and thick strata and the fracturing ratio to calculate the overburden failure height at the start of coal seam mining. Finally, when the thickness of the hard and thick strata, the overburden failure height, and the location of the hard and thick strata all meet preset conditions, the hard and thick strata are determined to be pre-fracturing hard and thick strata. This achieves controllable overburden failure during coal seam mining, provides a basis for judgment in the subsequent pre-fracturing process of the hard and thick strata, and thus improves the efficiency of coal seam mining.
[0106] In some embodiments, the device further includes a pre-splitting module 750 and a hard thick rock layer modification detection module 760.
[0107] The pre-splitting module 750 is used to pre-splitting the hard and thick rock layer after determining that it is a hard and thick rock layer that can be pre-splitting, so as to obtain the target hard and thick rock layer.
[0108] The hard thick rock layer modification detection module 760 is used to determine that the target hard thick rock layer is a modified hard thick rock layer when the ratio of the rock quality index in the target hard thick rock layer to the rock quality index of the pre-crackable hard thick rock layer is less than the rock quality index threshold.
[0109] The coal seam mining overburden control device provided in this embodiment of the invention pre-fracturing the hard and thick rock strata through high-pressure hydraulic fracturing, avoiding pollution to the groundwater environment, taking into account both environmental protection and coal seam mining cost constraints, and improving the environmental protection during coal seam mining.
[0110] Figure 8 An example is a schematic diagram of the physical structure of an electronic device, such as... Figure 8 As shown, the electronic device may include: a processor 810, a communication interface 820, a memory 830, and a communication bus 840, wherein the processor 810, the communication interface 820, and the memory 830 communicate with each other through the communication bus 840. The processor 810 can call logical instructions in the memory 830 to execute a coal seam mining overburden control method. This method includes: acquiring rock quality indicators of the coal seam roof, bedrock pillar thickness, and coal seam thickness; obtaining distribution information of the hard, thick rock strata based on the rock quality indicators, including the thickness and location of the hard, thick rock strata; obtaining the overburden failure height based on the coal seam thickness and a preset fracturing ratio; the fracturing ratio includes at least one of the ratio of the maximum height of the caving zone to the mining thickness and the ratio of the maximum height of the fracture zone to the mining thickness; and determining that the hard, thick rock strata are pre-fracturing hard, thick rock strata when the ratio of the hard, thick rock strata thickness to the coal seam thickness is greater than or equal to a thickness threshold, the overburden failure height is less than or equal to the bedrock pillar thickness, and the location is a preset target location, wherein the hard, thick rock strata are pre-fracturing hard, thick rock strata, and the target location includes a distance A from the hard, thick rock strata to the caving zone. h Location and distance of the thick, hard rock layer from the collapse zone B h At least one of the positions.
[0111] Furthermore, the logical instructions in the aforementioned memory 830 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, essentially, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.
[0112] On the other hand, the present invention also provides a computer program product, which includes a computer program that can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute the coal seam mining overburden control method provided by the above methods. The method includes: acquiring rock quality indicators of the coal seam roof, bedrock pillar thickness, and coal seam thickness; obtaining distribution information of hard and thick rock layers based on the rock quality indicators, the distribution information of hard and thick rock layers including the thickness and location of hard and thick rock layers; obtaining the overburden failure height based on the coal seam thickness and a preset fracture-to-mining ratio; the fracture-to-mining ratio includes at least one of the ratio of the maximum height of the caving zone to the mining thickness and the ratio of the maximum height of the fracture zone to the mining thickness; and determining that the hard and thick rock layer is a pre-fractureable hard and thick rock layer when the ratio of the thickness of the hard and thick rock layer to the coal seam thickness is greater than or equal to a thickness threshold, the overburden failure height is less than or equal to the bedrock pillar thickness, and the location is a preset target location, the hard and thick rock layer is determined to be a pre-fractureable hard and thick rock layer, the target location including the distance A between the hard and thick rock layer and the caving zone. h Location and distance of the thick, hard rock layer from the collapse zone B h At least one of the positions.
[0113] In another aspect, the present invention also provides a non-transitory computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the coal seam mining overburden control method provided by the above methods. This method includes: acquiring rock quality indicators of the coal seam roof, bedrock pillar thickness, and coal seam thickness; obtaining distribution information of hard, thick rock strata based on the rock quality indicators, the distribution information including the thickness and location of the hard, thick rock strata; obtaining the overburden failure height based on the coal seam thickness and a preset fracturing ratio; the fracturing ratio including at least one of the ratio of the maximum height of the caving zone to the mining thickness and the ratio of the maximum height of the fracture zone to the mining thickness; and determining that the hard, thick rock strata are pre-fracturing hard, thick rock strata when the ratio of the hard, thick rock strata thickness to the coal seam thickness is greater than or equal to a thickness threshold, the overburden failure height is less than or equal to the bedrock pillar thickness, and the location is a preset target location, wherein the hard, thick rock strata are pre-fracturing hard, thick rock strata, and the target location includes a distance A from the hard, thick rock strata to the caving zone. h Location and distance of the thick, hard rock layer from the collapse zone B h At least one of the positions.
[0114] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.
[0115] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.
[0116] 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 controlling overburden in coal seam mining, characterized in that, include: Obtain the rock quality indicators of the coal seam roof, the thickness of the bedrock pillar, and the thickness of the coal seam; Based on the rock quality indicators, the distribution information of the hard and thick rock layers is obtained, including the thickness and location of the hard and thick rock layers; Based on the coal seam thickness and the preset fracture-to-mining ratio, the overburden failure height is obtained; the fracture-to-mining ratio is the sum of the ratio of the maximum height of the caving zone to the mining thickness and the ratio of the maximum height of the fracture zone to the mining thickness. If the ratio of the thickness of the hard, thick rock layer to the thickness of the coal seam is greater than or equal to a thickness threshold, the overburden failure height is less than or equal to the thickness of the bedrock pillar, and the location is a preset target location, then the hard, thick rock layer is determined to be a pre-fractureable hard, thick rock layer. The target location includes a distance A from the hard, thick rock layer to the caving zone. h The location and the distance B of the hard, thick rock layer from the collapse zone h At least one of the positions; The hard, thick rock layer includes hard, thick rock layer A and hard, thick rock layer B, and the distance from A... h The distance B is the distance between the hard, thick rock layer A and the coal seam. h The distance between the hard, thick rock layer B and the coal seam is given. The fracture-to-mining ratio corresponding to the hard, thick rock layer A is the ratio of the maximum height of the overburden fracture zone to the mining thickness, C0. The fracture-to-mining ratio corresponding to the hard, thick rock layer B is the ratio of the maximum height of the overburden collapse zone to the mining thickness, C1. The determination that the ratio of the thickness of the hard, thick rock layer to the thickness of the coal seam is greater than or equal to a thickness threshold, the overburden failure height is less than or equal to the thickness of the bedrock pillar, and the location is a preset target location includes: The distance B h Greater than or equal to 2M and less than or equal to MC0, where M is the thickness of the coal seam; The distance A h Greater than or equal to MC0, and less than or equal to 0.8M(C0+C1)-A m A m The thickness of the hard, thick rock layer A is given.
2. The method for controlling overburden in coal seam mining according to claim 1, characterized in that, After determining that the hard, thick rock layer is a hard, thick rock layer that can be pre-fractured, the method further includes: The pre-fractured hard and thick rock strata are subjected to pre-fracture treatment to obtain the target hard and thick rock strata; If the ratio of the rock quality index in the target hard thick rock layer to the rock quality index of the pre-fractureable hard thick rock layer is less than the rock quality index threshold, the target hard thick rock layer is determined to be a modified hard thick rock layer.
3. The method for controlling overburden in coal seam mining according to claim 2, characterized in that, The process of pre-fractured the pre-fractureable hard and thick rock strata to obtain the target hard and thick rock strata includes: When the thickness of the hard rock layer is less than or equal to the hard rock layer thickness threshold, boreholes are drilled along multiple vertical centers of the hard rock layer to obtain the target hard rock layer. Wherein, the distance between the boreholes on both sides of the hard thick rock stratum is greater than the dip width of the mining face, and the distance between the borehole on each side and the roadway of the working face is greater than or equal to the distance T, wherein the distance T is determined based on the distance between the target hard thick rock stratum and the coal seam.
4. The method for controlling overburden in coal seam mining according to any one of claims 2-3, characterized in that, The process of pre-fracture the pre-fractureable hard thick rock layer to obtain the target hard thick rock layer further includes: When the thickness of the hard rock layer is greater than the hard rock layer thickness threshold, and the difference between the thickness of the hard rock layer and the hard rock layer thickness threshold exceeds the distance threshold, the number of borehole rows is determined based on the distance threshold and the difference. Based on the number of borehole rows, boreholes are drilled along multiple vertical centers of the hard, thick rock layer to obtain the target hard, thick rock layer.
5. A coal seam mining overburden control device, employing the coal seam mining overburden control method as described in claim 1, characterized in that, The device includes: The acquisition module is used to acquire the rock quality indicators of the coal seam roof, the thickness of the bedrock pillar, and the thickness of the coal seam. The hard and thick rock layer detection module is used to obtain the distribution information of the hard and thick rock layer based on the rock quality index. The distribution information of the hard and thick rock layer includes the thickness and location of the hard and thick rock layer. The overburden failure range detection module is used to obtain the overburden failure height based on the coal seam thickness and a preset fracture-to-mining ratio; the fracture-to-mining ratio is the sum of the ratio of the maximum height of the caving zone to the mining thickness and the ratio of the maximum height of the fracture zone to the mining thickness. The pre-fractureable hard thick rock strata detection module is used to determine that the hard thick rock strata are pre-fractureable hard thick rock strata when the ratio of the thickness of the hard thick rock strata to the thickness of the coal seam is greater than or equal to a thickness threshold, the overburden failure height is less than or equal to the thickness of the bedrock pillar, and the location is a preset target location. The target location includes a distance A from the hard thick rock strata to the caving zone. h The location and the distance B of the hard, thick rock layer from the collapse zone h At least one of the positions.
6. The coal seam mining overburden control device according to claim 5, characterized in that, The device further includes: The pre-splitting module is used to pre-splitting the hard and thick rock layer after determining that the hard and thick rock layer is a pre-splitting hard and thick rock layer, so as to obtain the target hard and thick rock layer. The hard thick rock layer modification detection module is used to determine that the target hard thick rock layer is a modified hard thick rock layer when the ratio of the rock quality index in the target hard thick rock layer to the rock quality index of the pre-fractureable hard thick rock layer is less than the rock quality index threshold.
7. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the coal seam mining overburden control method as described in any one of claims 1 to 4.
8. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the coal seam mining overburden control method as described in any one of claims 1 to 4.
9. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by the processor, it implements the coal seam mining overburden control method as described in any one of claims 1 to 4.