Full space-time joint prevention and control method for repeated mining water inrush risk of deep close-distance coal seam group

Abstract

The invention provides a full space-time joint prevention and control method for repeated mining water inrush risk of a deep close-distance coal seam group. The method comprises the steps that a working face roadway arrangement scheme is optimized through physical simulation and numerical simulation before stoping, an open-off cut and inclination double-internal-error arrangement mode is formed, and floor roadway arrangement is conducted; the thickness of a water-resisting layer is increased through area treatment before stoping, so that the water inrush coefficient is reduced; monitoring time, space and intensity information of a micro-seismic event in the area during recovery, and determining a micro-seismic monitoring early warning level; and observing a mine pressure value and hydrological information during stoping, paying attention to changes of the mine pressure value and the hydrological information, and performing pushing and mining speed control and fixed-point dynamic water drainage and pressure reduction in combination with a micro-seismic monitoring early warning level and a deep event dense area so as to reduce a water inrush coefficient of a working face. Through combined control of three methods of mine pressure, water pressure and micro-seismic monitoring and early warning, the water inrush risk can be reduced and safe mining of the working face can be guaranteed through the whole time period before mining and during mining.

Description

Technical Field

[0001] The present invention relates to the fields of coal seam technology and coal mine water hazard prevention and control, and in particular to a full-time and space joint prevention and control method for water inrush risk caused by repeated mining of deep and close-range coal seams. Background Art

[0002] Coal is an important basic energy source in my country, but there are differences in the occurrence conditions of coal resources, and there are different forms of safety issues in mining. The characteristics of extremely close-distance coal seams are that the distance between coal seams is close, the impact of adjacent coal seams during mining is significant, and the surrounding rock of the tunnel is severely deformed due to repeated mining. The intensity of the mine pressure increases, which greatly increases the threat of floor water hazards under repeated mining conditions, and the difficulty of water prevention and control increases. During the mining process, it is very easy to cause abnormal fluctuations in mine water inrush, which seriously threatens the safety of mine production.

[0003] At present, the prevention and control of water hazards in the mining of close-range coal seams is mainly achieved through strengthening hydrological observations, combining physical drilling with exploration of abnormal areas, etc., but dynamic control has not been achieved, and the means are relatively single. The effect of reducing the risk of water inrush needs to be improved. Summary of the invention

[0004] An embodiment of the present invention provides a method for joint prevention and control of water inrush risks during repeated mining of deep and close-range coal seams in all time and space, so as to solve the problem of reducing the risk of water inrush during mining of extremely close-range coal seams.

[0005] In the first aspect, an embodiment of the present invention provides a method for joint prevention and control of water inrush risk caused by repeated mining of deep and close-range coal seams in all time and space, including:

[0006] Before mining, the working face tunnel layout plan is optimized through physical simulation and numerical simulation to form a cutting eye and inclined double internal staggered layout, and the floor tunnel layout is carried out;

[0007] Before mining, the thickness of the aquiclude can be increased through regional management to reduce the water inrush coefficient;

[0008] During mining, the time, space and intensity information of microseismic events in the monitoring area are monitored, and the microseismic monitoring warning level is determined;

[0009] During mining, the mine pressure value and hydrological information are observed and their changes are paid attention to. At the same time, combined with the microseismic monitoring warning level and the deep event-intensive area, the mining speed is controlled and the fixed-point dynamic drainage and pressure reduction are carried out to reduce the water inrush coefficient of the working face.

[0010] In one possible implementation, the layout of the working face tunnels is optimized by physical simulation before mining, including:

[0011] Make a physical simulation model according to the similar scale with reference to the scale of the working face, and select the components of the physical simulation model according to the actual geological data of the mine;

[0012] Based on the physical simulation model, the roof was linearly pressurized in combination with the mining advancement time and the combined mechanical properties of the roof coal and rock mass. The bottom plate was pressurized with a spring to simulate the bottom plate water pressure, and a group of comparison schemes were compared. Among them, the comparison scheme was consistent with the dip alignment conditions, and the cut eye alignment and cut eye internal offset were compared.

[0013] In one possible implementation, the layout of the working face tunnels is optimized by numerical simulation before mining, including:

[0014] Based on the borehole histogram of the monitoring working face, the physical and mechanical parameters of the surrounding rock and coal seam, a model of the movement law of the overburden rock during coal seam mining based on fluid-solid coupling simulation is established;

[0015] The orthogonal experimental design method was adopted, and three influencing factors, namely, cut-eye arrangement, dip arrangement and mining speed, were selected. Cut-eye alignment, cut-eye internal deviation, dip alignment, dip protrusion, dip internal deviation, slow mining, medium speed mining and fast mining were used as simulation factors and levels. Based on the overburden movement law model, the simulation factors and levels were combined and compared.

[0016] In one possible implementation method, the water pressure at the working face is reduced by regional treatment before mining to increase the thickness of the impermeable layer and reduce the water inrush coefficient, including:

[0017] Before mining, the thickness of the impermeable layer is increased through regional management, the water inrush coefficient in normal areas is controlled at 0.06MPa / m, and the water inrush coefficient in weak areas is controlled at 0.04MPa / m through water drainage.

[0018] In a possible implementation, the fixed-point dynamic hydrophobic pressure reduction includes:

[0019] When the working face is under pressure or the water volume change is greater than the preset water volume change threshold, the drainage time of the drainage borehole is controlled by the valve;

[0020] According to the mining conditions, water is released in the geological structure area, the microseismic deep event intensive area and the primary fracture zone;

[0021] The effect of depressurization is evaluated based on the changes in water level after depressurization and the changes in mine water inflow.

[0022] In a possible implementation, determining the microseismic monitoring warning level includes:

[0023] If the daily amplitude of the bottom plate event is higher than the first preset threshold and lower than the second preset threshold, or microseismic events occur in the relatively water-rich thin limestone, the warning level is level 4;

[0024] If the daily amplitude of the bottom plate event exceeds the second preset threshold for 2 days within 7 days, or the main relatively water-rich thin limestone event occurs for 2 days within 7 days, or the Ordovician limestone event occurs, the warning level is level 3;

[0025] If the daily amplitude of the bottom plate events exceeds the third preset threshold for 5 days within 7 days, or the main relatively water-rich thin-layer limestone events occur for 5 days within 7 days, or the Ordovician limestone events occur for 3 days within 7 days, or the bottom plate microseismic events near the mining line are clustered in an up-and-down manner, the warning level is level 2;

[0026] If the Level 2 warning occurs for three consecutive days and an Aohui event occurs for three consecutive days, the warning level will be Level 1;

[0027] Based on the microseismic monitoring warning level and the deep event intensive area, the mining speed control and fixed-point dynamic drainage and pressure reduction are carried out, including:

[0028] The pressure intensity is determined based on the frequency change rate of microseismic events and the energy index, and prevention and control measures corresponding to the pressure intensity are taken; among them, the prevention and control measures include adjusting support measures, speed control and water pressure control.

[0029] In a possible implementation, the pushing and mining speed control includes:

[0030] The mining speed in deep event-intensive areas is controlled at 1.2 to 2 times the normal mining speed.

[0031] In a second aspect, an embodiment of the present invention provides a full-time and space joint prevention and control device for repeated mining of water inrush risk in deep and close-range coal seams, comprising:

[0032] The optimization module is used to optimize the layout of the working face tunnels through physical simulation and numerical simulation before mining, form the layout of cutting eyes and inclined double internal staggering, and arrange the floor tunnels;

[0033] The treatment module is used to increase the thickness of the aquiclude through regional treatment before mining to reduce the water inrush coefficient;

[0034] The monitoring module is used to monitor the time, space and intensity information of microseismic events in the mining area and determine the microseismic monitoring warning level;

[0035] The dewatering module is used to observe the mine pressure value and hydrological information during mining and pay attention to their changes. At the same time, combined with the microseismic monitoring warning level and deep event-intensive areas, it controls the mining speed and performs fixed-point dynamic dewatering and pressure reduction to reduce the water inrush coefficient of the working face.

[0036] In a third aspect, an embodiment of the present invention provides a terminal, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the steps of the method described in the first aspect or any possible implementation manner of the first aspect are implemented.

[0037] In a fourth aspect, an embodiment of the present invention provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the method described in the first aspect or any possible implementation of the first aspect are implemented.

[0038] The embodiment of the present invention provides a method for joint prevention and control of water inrush risk in deep and close-range coal seam groups in all time and space. It uses simulation data analysis to analyze important parameters such as pressure step distance and floor damage depth, and arranges floor lanes to achieve mine pressure control; it uses dynamic drainage and pressure reduction, regional governance and other measures to achieve water pressure management; it combines the frequency and depth of microseismic events to analyze the spatiotemporal evolution of events, and takes different measures according to early warning to dynamically control water drainage or reduce the concentration of mine pressure. Dynamic joint control is achieved through the integration of mine pressure, water pressure, and microseismic monitoring and early warning, which runs through the entire period before mining and mining, reduces the risk of water inrush, and ensures safe mining of the working face. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0040] Figure 1 It is a flow chart for realizing a method for joint prevention and control of water inrush risk in deep and close-range coal seam groups during repeated mining in all time and space provided by an embodiment of the present invention;

[0041] Figure 2 is a structural schematic diagram of a microseismic high-precision monitoring system provided by an embodiment of the present invention;

[0042] Figure 3 It is a technical roadmap for joint prevention and control provided by an embodiment of the present invention;

[0043] Figure 4A It is a schematic diagram of a working face laneway arrangement of cut-eye alignment and inclination alignment provided by an embodiment of the present invention;

[0044] Figure 4B It is a schematic diagram of a working face laneway arrangement with inward staggering of cuts and inclination alignment provided by an embodiment of the present invention;

[0045] Figure 5A It is a schematic diagram of the experimental floor failure depth when the working face tunnel arrangement is aligned with the cutting eye provided by an embodiment of the present invention;

[0046] Figure 5B It is a schematic diagram of the experimental floor failure depth of the working face tunnel arrangement as the cut-eye inner stagger provided by an embodiment of the present invention;

[0047] Figure 6 This is a physical simulation test point experimental diagram provided by an embodiment of the present invention;

[0048] Fig. 7A It is a schematic diagram of pressure values ​​for non-stop mining provided by an embodiment of the present invention;

[0049] Figure 7B This is a schematic diagram of the pressure value of a 24-day mining suspension provided by an embodiment of the present invention.

[0050] Figure 8 This is a comparison diagram of the change of bottom plate damage depth at different speeds provided by an embodiment of the present invention;

[0051] Fig. 9A This is a comparison diagram of horizontal displacement at a speed of 2 m / d provided by an embodiment of the present invention;

[0052] Fig. 9B This is a comparison diagram of horizontal displacement at a speed of 4 m / d provided by an embodiment of the present invention;

[0053] Fig. 9C This is a comparison diagram of horizontal displacement at a speed of 8 m / d provided by an embodiment of the present invention;

[0054] Fig.10 It is a 17-33200 bar chart provided by an embodiment of the present invention;

[0055] Fig.11 A microseismic event distribution diagram showing different perspectives of XY, XZ, and YZ provided by an embodiment of the present invention;

[0056] Fig.12 is a microseismic monitoring layer distribution table provided by an embodiment of the present invention;

[0057] Fig.13 This is an example diagram of daily warning of microseismic monitoring provided by an embodiment of the present invention;

[0058] Fig.14 It is a schematic diagram of a process of delineating a deep event intensive area provided by an embodiment of the present invention;

[0059] Fig.15 It is a schematic diagram of the structure of a full-time and space joint prevention and control device for repeated mining of water inrush risk in deep and close-range coal seams provided by an embodiment of the present invention;

[0060] Fig.16 is a schematic diagram of a terminal provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0061] In the following description, specific details such as specific system structures, technologies, etc. are provided for the purpose of illustration rather than limitation, so as to provide a thorough understanding of the embodiments of the present invention. However, it should be clear to those skilled in the art that the present invention may be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to prevent unnecessary details from obstructing the description of the present invention.

[0062] In order to make the purpose, technical solutions and advantages of the present invention more clear, specific embodiments will be described below in conjunction with the accompanying drawings.

[0063] See also Figure 1 , which shows a flow chart for implementing a method for joint prevention and control of water inrush risk in deep and close-range coal seam groups in all time and space provided by an embodiment of the present invention, and is described in detail as follows:

[0064] Step 101, before mining, optimize the working face tunnel layout plan through physical simulation and numerical simulation, form a cutting eye and inclined double inner staggered layout, and arrange the bottom plate tunnel.

[0065] In this embodiment, before mining, when designing the tunnels at the working face, different layout schemes are compared through physical simulation, numerical simulation, etc., and important parameters such as step distance and floor damage depth are pressed through physical and numerical simulation data analysis. After the upper layer is mined, the mining scale of the lower layer is appropriately reduced, and the cutting and internal deviation of the upper and lower tunnels are carried out, which is conducive to reducing the floor damage depth and timely collapse of the overlying surrounding rock during mining.

[0066] Through the arrangement of the floor roadway, the floor rock mass of the working face can be relieved in advance. The excavation of the floor roadway can properly relieve the pressure of the floor coal rock mining, especially when the coal seam group is superimposed and mined, the pressure relief effect is more significant.

[0067] Step 102, before mining, the thickness of the aquiclude is increased through regional management to reduce the water inrush coefficient.

[0068] In this embodiment, the floor water prevention and control should follow the principle of combining surface and underground management, and combining regional and local management. According to the actual situation of the mine, water prevention and control measures such as surface regional management, underground grouting to reinforce the floor or transform the aquifer, water drainage and pressure reduction, and backfill mining are adopted to eliminate the threat of water damage.

[0069] In addition, by collating the simulation experimental data of step 101, it was found that the inner offset of the cutting eye can effectively control the bottom plate damage depth and the initial pressure step distance, which can relatively increase the thickness of the effective waterproof layer and relatively improve the safety of the lower layer recovery.

[0070] Step 103, monitoring the time, space, and intensity information of microseismic events in the area during mining, and determining the microseismic monitoring warning level.

[0071] In this embodiment, microseismic events have multi-dimensional information such as time, space, and intensity. After accurate positioning, the frequency, location, and energy of the earthquake source can be intuitively displayed. A high-precision microseismic monitoring system is installed on the working face, such as Figure 2 As shown in the figure, the microseismic high-precision monitoring system includes geophones, monitoring substations, etc., which can obtain events in the study area in real time. After underground acquisition and transmission, ground transmission and triggering, data processing and output, a daily microseismic monitoring report is generated.

[0072] Step 104, during mining, the mine pressure value and hydrological information are observed and their changes are noted. Meanwhile, combined with the microseismic monitoring warning level and the deep event-intensive area, mining speed control and fixed-point dynamic drainage and pressure reduction are performed to reduce the water inrush coefficient of the working face.

[0073] In this embodiment, according to the distribution of events in the relatively water-rich thin limestone layer, also known as the microseismic monitoring and early warning layer, a deep event-intensive area is delineated, which is the deep fracture development area. Corresponding measures should be taken to reduce the risk of water inrush 100 meters before entering the area and during entering the area.

[0074] The collected data is uploaded to the ground server via optical fiber, and then quality controlled in professional processing software. Professional mapping software is used to display microseismic events from different perspectives, and the temporal and spatial evolution of events is analyzed in combination with indicators such as the frequency and depth of microseismic events. A daily microseismic monitoring report is issued. When the microseismic monitoring daily data triggers the warning conditions, the corresponding level of warning is issued to the mine. The mine takes different measures according to the warning to drain water or reduce the concentration of mine pressure to reduce the risk of water inrush.

[0075] At the same time, when passing through the original damaged zone or the structural anomaly area, a uniform and rapid passage is adopted, and the speed is generally 1.2 to 2 times the pushing and mining speed of the normal section. After passing through the original damaged zone or the structural anomaly area, the normal pushing and mining speed is restored to avoid the local concentration of mine pressure.

[0076] The embodiment of the present invention realizes mine pressure control by analyzing important parameters such as pressure step distance and floor damage depth through simulation data, and arranges floor lanes; realizes water pressure management through dynamic drainage and pressure reduction, regional governance and other measures; analyzes the spatiotemporal evolution of events in combination with indicators such as the frequency and depth of microseismic events, and takes different measures according to early warning to drain water or reduce the concentration of mine pressure. Dynamic joint control is achieved through the integration of mine pressure, water pressure, and microseismic monitoring and early warning, which runs through the entire period before mining and mining, reduces the risk of water inrush, and ensures safe mining of the working face.

[0077] In one possible implementation, the layout of the working face tunnels is optimized by physical simulation before mining, including:

[0078] Make a physical simulation model according to the similar scale with reference to the scale of the working face, and select the components of the physical simulation model according to the actual geological data of the mine;

[0079] Based on the physical simulation model, the roof was linearly pressurized in combination with the mining advancement time and the combined mechanical properties of the roof coal and rock mass. The bottom plate was pressurized with a spring to simulate the bottom plate water pressure, and a group of comparison schemes were compared. Among them, the comparison scheme was consistent with the dip alignment conditions, and the cut eye alignment and cut eye internal offset were compared.

[0080] In this embodiment, the physical simulation makes a model according to a similar scale with reference to the scale of the working face, and selects the components of similar simulation materials according to the actual geological data of the mine, to ensure that the model and the entity meet geometric similarity, time similarity and mechanical properties. The comparison scheme is consistent with the inclination alignment conditions, and the cut eye alignment and cut eye internal offset are compared. In the physical simulation, the roof of the similar model adopts a linear pressurization method. The pressure strength varies with the advancement of mining. At the same time, combined with the difference in the mechanical properties of the roof coal and rock mass, different degrees of pressurization are performed. The bottom plate adopts spring pressurization to simulate the bottom plate pressure water pressure, so that the simulation results are closer to the actual mining.

[0081] In one possible implementation, the layout of the working face tunnels is optimized by numerical simulation before mining, including:

[0082] Based on the borehole histogram of the monitoring working face, the physical and mechanical parameters of the surrounding rock and coal seam, a model of the movement law of the overburden rock during coal seam mining based on fluid-solid coupling simulation is established;

[0083] The orthogonal experimental design method was adopted, and three influencing factors, namely, cut-eye arrangement, dip arrangement and mining speed, were selected. Cut-eye alignment, cut-eye internal deviation, dip alignment, dip protrusion, dip internal deviation, slow mining, medium speed mining and fast mining were used as simulation factors and levels. Based on the overburden movement law model, the simulation factors and levels were combined and compared.

[0084] In this embodiment, the numerical simulation refers to the borehole columnar diagram of the monitored working face, the physical and mechanical parameters of the surrounding rock and the coal seam, and establishes a model of the movement law of the overlying rock during coal seam mining. The following boundary conditions are generally adopted: fixed horizontal displacement of the left and right boundaries, fixed vertical displacement of the bottom boundary, and the top is a free boundary.

[0085] The numerical simulation adopts the fluid-solid coupling simulation method and is designed using the orthogonal experimental design method to determine the factors related to the optimization of tunnel layout and mining. The orthogonal table is selected by the influencing factors and the number of levels, and the cut-eye alignment, cut-eye internal deviation, inclination alignment, inclination protrusion, inclination internal deviation, slow mining, medium-speed mining, and fast mining are filled into the orthogonal table to form a specific experimental plan, record the comparative experimental results of each group, and calculate the contribution coefficient and range of each influencing factor to finally determine the optimal combination. The corresponding relationship between the simulation factors and the levels is shown in Table 1.

[0086] Table 1

[0087]

[0088] In one possible implementation method, the thickness of the aquiclude is increased by regional treatment before mining to reduce the water inrush coefficient, including:

[0089] Before mining, the thickness of the impermeable layer is increased through regional management, the water inrush coefficient in normal areas is controlled at 0.06MPa / m, and the water inrush coefficient in weak areas is controlled at 0.04MPa / m through water drainage.

[0090] In this embodiment, according to the calculation formula of water inrush coefficient in Appendix 5 of the "Detailed Rules for Water Control in Coal Mines", it is applicable to coal mining working faces. According to national data, the water inrush coefficient of areas with structural damage to the bottom plate shall generally not be greater than 0.06MPa / m, and the water inrush coefficient of areas with intact impermeable layers and no fracture structural damage shall not be greater than 0.1MPa / m. The calculation formula of water inrush coefficient is:

[0091]

[0092] Wherein, T is water inrush coefficient, MPa / m; P is the actual water head value borne by the bottom plate aquiclude, MPa; the water pressure should be calculated from the top interface of the aquifer, and the water level value shall be the highest value of the aquifer observed in the past three years; M is the thickness of the bottom plate aquiclude, m.

[0093] In this embodiment, the water pressure is reduced by dynamic drainage and pressure reduction, regional management and other measures to increase the thickness of the waterproof layer, thereby reducing the water inrush coefficient and achieving strict management of the water pressure on the working face. The normal section is controlled at 0.06MPa / m, and the weak area is controlled at 0.04MPa / m through drainage, ensuring safe production on the working face.

[0094] In a possible implementation, the fixed-point dynamic hydrophobic pressure reduction includes:

[0095] When the working face is under pressure or the water volume change is greater than the preset water volume change threshold, the drainage time of the drainage borehole is controlled by the valve;

[0096] According to the mining conditions, water is released in the geological structure area, the microseismic deep event intensive area and the primary fracture zone;

[0097] The effect of depressurization is evaluated based on the changes in water level after depressurization and the changes in mine water inflow.

[0098] In this embodiment, the main measure of water pressure control is fixed-point dynamic drainage. During mining, when the floor water inrush coefficient is higher than 0.06MPa / m, or when weak areas such as structures and original damaged zones are passed, the high-pressure aquifer in the deep coal seam floor is drained and depressurized, and water-pressure mining is carried out under the condition of reducing the head pressure. The drainage borehole directly enters the water-filled rock layer (body) that needs drainage, which is used to disperse the drainage or local drainage, reduce the water pressure value, and thus reduce the water inrush coefficient.

[0099] Drainage and pressure reduction is a dynamic control method. ① When the working face is under pressure or the water volume changes greatly, the drainage time is controlled by a valve to achieve temporal dynamics. ② Reasonable drainage is carried out according to the mining conditions. Common locations include geological structure areas, microseismic deep event intensive areas, primary fracture zones, etc., which can achieve positional dynamics.

[0100] During the drainage process, attention should be paid to matching the corresponding mine drainage system, improving the drainage capacity, and ensuring the drainage capacity of deep and thick limestone water.

[0101] In this embodiment, by establishing an automatic water level observation system, the changes in water level after drainage and pressure reduction, as well as the changes in the amount of water inflow in the mine are monitored in real time, so as to evaluate the effect of drainage and pressure reduction. The automatic water level observation system includes hydrological sensors, measuring stations, transmission equipment, servers, and a water hazard risk warning information display platform. The main steps of its establishment are: select a suitable measuring point location within the coal mine, install water level and water volume sensing equipment, transmit to the server through the network, and upload a water level and water volume data to the monitoring platform every 4 hours. The monitoring platform can query and display real-time and cumulative values. When the water level and water volume data in the platform reach the warning value, the platform will issue a warning prompt and push it to relevant personnel through the mobile phone, and the drainage hole valve will be opened in time for drainage.

[0102] In a possible implementation, determining the microseismic monitoring warning level includes:

[0103] If the daily amplitude of the bottom plate event is higher than the first preset threshold and lower than the second preset threshold, or microseismic events occur in the relatively water-rich thin limestone, the warning level is level 4;

[0104] If the daily amplitude of the bottom plate event exceeds the second preset threshold for 2 days within 7 days, or the main relatively water-rich thin limestone event occurs for 2 days within 7 days, or the Ordovician limestone event occurs, the warning level is level 3;

[0105] If the daily amplitude of the bottom plate events exceeds the third preset threshold for 5 days within 7 days, or the main relatively water-rich thin-layer limestone events occur for 5 days within 7 days, or the Ordovician limestone events occur for 3 days within 7 days, or the bottom plate microseismic events near the mining line are clustered in an up-and-down manner, the warning level is level 2;

[0106] If the Level 2 warning occurs for three consecutive days and an Aohui event occurs for three consecutive days, the warning level will be Level 1;

[0107] Based on the microseismic monitoring warning level and the deep event intensive area, the mining speed control and fixed-point dynamic drainage and pressure reduction are carried out, including:

[0108] The pressure intensity is determined based on the frequency change rate and energy index of microseismic events, and prevention and control measures corresponding to the pressure intensity are taken; among them, the prevention and control measures include support measures, speed control and water pressure control.

[0109] In this embodiment, specific microseismic monitoring and early warning triggering conditions may be as shown in Table 2.

[0110] Table 2

[0111]

[0112]

[0113] Combined with microseismic identification, the mine pressure is controlled and the parameters used include:

[0114] Parameter 1 Microseismic event frequency change rate

[0115]

[0116] Where N n is the number of microseismic events on that day, in units of pieces, N n-1 is the number of microseismic events on the previous day, in units;

[0117] Parameter 2 Energy Index (EI)

[0118] The energy index can be used to describe the degree of damage to the rock mass when microseismic occurs. Combined with the actual situation of the working face, see formula (2).

[0119]

[0120] Where Ep is the energy of microseismic events within a single day, in J. is the average energy value of microseismic events during the monitoring period, in J.

[0121] The pressure intensity corresponding to the microseismic event can be determined based on the parameters f and EI. According to the different pressure intensities, corresponding measures can be taken, including support measures and velocity control. At the same time, combined with hydrological information, water pressure control measures can be appropriately supplemented.

[0122] In a possible implementation, the pushing and mining speed control includes:

[0123] The mining speed in deep event-intensive areas is controlled at 1.2 to 2 times the normal mining speed.

[0124] In this embodiment, through the actual measurement and statistics of on-site microseismic data, numerical simulation of the changes in pressure values ​​at different mining speeds, and the impact of temporary suspension of production and resumption of mining on the working face, hydrological changes and microseismic monitoring, mine pressure support values, etc. are combined in mining.

[0125] From the above, it can be seen that before the repeated mining of the lower layers of the coal seam group at a very close distance, the present invention reduces the risk of water inrush by arranging the double internal staggering of the cutting eye and the inclination of the lower layer tunnel, excavating the bottom plate tunnel, grouting reinforcement before mining, and draining water. During mining, the water inrush coefficient of the working face is reduced by combining real-time microseismic monitoring and early warning, speed control in deep event-intensive areas, and draining water. Through the joint control of the three methods of water pressure, mine pressure, and microseismic monitoring and early warning, throughout the entire period before mining and during mining, the water inrush coefficient in normal areas is not greater than 0.06MPa / m, and the water inrush coefficient in weak areas such as structural areas is not greater than 0.04MPa / m, ensuring the safe mining of the working face.

[0126] In a specific embodiment, the specific implementation of the present invention is described by taking Pingmei No. 10 Mine as an example. The mining geological conditions of Pingmei No. 10 Mine are deep burial, high water pressure, and high water temperature, which lead to large structural stress, severe mine pressure, great thermal damage threat, and serious water inrush threat. The technical roadmap for comprehensive control is as follows: Figure 3 As shown, the details are as follows:

[0127] 1. Mine pressure control

[0128] (1) Working face tunnel layout

[0129] ①Physical simulation

[0130] Physical simulation experiments have the advantages of strong intuitiveness, high flexibility, and good repeatability. They can vividly and intuitively depict the deformation and fracture process of the coal seam roof and floor under the influence of mining. According to the specific conditions of Pingmei Ji 17-33200, the alignment and internal misalignment of the cut eye are simulated. The working face is mainly affected by the mining stress and the uplift stress of the deep limestone aquifer, and the roof and floor failure law and the difference in the development of the roof and floor cracks are also simulated. A set of comparative schemes for physical simulation are as follows Figure 4A , Figure 4B As shown, Figure 4AThe working face tunnel layout is cut eye alignment, inclination alignment, Figure 4B The working face tunnel arrangement is staggered inward and aligned inclination.

[0131] Record the experimental process, take pictures of the experimental bottom plate damage depth, and analyze the bottom plate damage depth. Figure 5A The working face tunnel layout is cut eye alignment, Figure 5B The working face tunnel layout is staggered inward.

[0132] The experimental data in the simulation process were organized into a table, and it was found that the internal offset of the cut effectively controlled the floor failure depth and the initial pressure step, and the thickness of the effective waterproof layer was relatively increased, which relatively improved the safety of the lower layer mining. Table 3 is a data comparison table of different layout methods.

[0133] Table 3

[0134] First time pressing step distance Cycle pressure step Depth of bottom plate damage Cutting eye alignment 36m 24m 38m Intraocular misalignment 30m 24m 33m

[0135] ② Numerical simulation

[0136] The numerical simulation was carried out for four methods: "cut eye alignment, inclination inward deviation", "cut eye inward deviation, inclination inward deviation", "cut eye inward deviation, inclination alignment", and "cut eye inward deviation, inclination protrusion". The data were sorted and listed in a table. From the data in the table, it can be seen that the cut eye inward deviation, inclination inward deviation, the pressure value is the smallest, and the bottom plate damage depth is also the smallest. Table 4 is a comparison table of various numerical simulation methods.

[0137] Table 4

[0138]

[0139] Based on the above-mentioned physical simulation, numerical simulation and other analyses, the 33200 working face of Pingmei No. 10 Mine finally adopted the layout of "70m inward offset of the cutting eye and inward offset of the inclination".

[0140] (2) Floor tunnel layout

[0141] The bottom plate tunnel is arranged 12 to 22.5 meters below the bottom plate of the J15-33200 machine, ventilation tunnel and cut-eye.

[0142] (3) Determination of the recovery speed when the working face passes through the deep primary fracture zone

[0143] ① Comparison of whether the mining is suspended

[0144] Figure 6 This is a diagram of the physical simulation test point experiment. Fig. 7A This is a schematic diagram of the pressure value for non-stop mining. Figure 7B This is a schematic diagram of the pressure value after the mining is suspended for 24 days.

[0145] like Figure 6 , Fig. 7A , Figure 7B As shown, in the initial stage of re-mining of the working face, the stress mutation value increases sharply, the disturbance degree of the bottom plate increases, and the mining should be resumed without stopping if a small amount of water comes out of the bottom plate.

[0146] ② Comparison of floor damage depth at different mining speeds

[0147] Figure 8 This is a comparison chart of the changes in bottom plate damage depth at different speeds. Within a certain speed range, the faster the advancement speed, the smaller the bottom plate damage depth.

[0148] Figure 9A-9C is a comparison chart of horizontal displacement at different speeds, where Fig. 9A The speed is 2m / d, Fig. 9B The speed is 4m / d, Fig. 9C The speed is 8m / d, Figure 9A-9C It can be seen that the impact distance of horizontal displacement is reduced from 1300m to 800m to 450m. However, considering that the stress release is too fast when the speed is too fast, it is not conducive to the collapse of the roof. When the working face passes through the deep primary fracture area, it adopts a uniform speed of 1.2 to 2 times the normal recovery speed. The water volume of the working face does not change much, ensuring safe production.

[0149] 2. Water pressure control

[0150] The mining of the Ji15-33200 working face overlying the Ji17-33200 in Pingmei has been completed, and water inrush occurred in the floor roadway during the mining process. The floor roadway is 12 to 22.5 meters below the machine, wind roadway and cut-eye floor of Ji15-33200, and the maximum water inflow reaches 260.3m3 / h, and finally stabilizes at 160m3 / h. The permeability coefficient of the Cambrian limestone in Ji17-33200 is 0.000402 to 0.726m / d. The water level of the 26th observation hole near the Ji17-33200 working face is -687.4m, and the lowest elevation of the working face is -962m. The water pressure of the Cambrian limestone water on the Ji17-33200 working face is 2.75MPa. According to the actual exposure of the working face and the analysis of the exposure data of the limestone water drilling hole in the floor roadway, the thickness of the coal seam floor to the Cambrian limestone roof of the working face is about 86m. The depth of floor damage is about 32m, so the critical water inrush coefficient is 0.04MPa / m, the safety water pressure is 2.16MPa (i.e. 220.4m), and the drainage pressure relief head value S is 108.2m. The Tenth Mine drilled 13 water prevention and control holes in the wind tunnel section, machine tunnel and cut-eye construction of the rock protection layer working face in the 33200 section. On the one hand, the drilling verification of the abnormal water-rich area was carried out, and on the other hand, the drilling holes can be used to implement drainage pressure relief and eliminate threats.

[0151] 3. Real-time monitoring and early warning control of microseismic events

[0152] The structure of the microseismic real-time monitoring and early warning system is as follows: Figure 2As shown in the figure, 10 detectors are arranged in the two lanes of the flat coal working face, and 2 acquisition substations are set up with a spacing of 80 to 100 meters.

[0153] Fig.10 This is the bar chart of 17-33200. Fig.10 As shown in the figure, according to the hydrogeological conditions of the working face and the mining engineering drawings, it is divided into six strata: 30m shallower than the upper roof of Ji-17 coal, 30m from the roof of Ji-17 coal to the bottom of Ji-17 coal, the upper section of Carboniferous limestone (0-40m from the bottom of Ji-17 coal), the middle section of Carboniferous limestone (40-65m from the bottom of Ji-17 coal), the lower section of Carboniferous limestone (65-92m from the bottom of Ji-17 coal), and the top interface of Cambrian limestone. Among them, the shallower bottom of Ji-17 coal seam is the roof event, and the deeper bottom of Ji-17 coal seam is the bottom event.

[0154] Fig.11 Display microseismic event distribution diagrams from different perspectives: XY, XZ, and YZ. Fig.12 is the distribution table of microseismic monitoring layers. For example, during the monitoring process, the distribution of microseismic events on a certain day is as follows: Fig.11 The distribution of events in each layer is shown in Fig.12 As shown in the figure, there are more events near the top and bottom of the coal seam, accounting for a large proportion. However, the middle limestone section affected by deep water movement and its deep section are the key focus of microseismic monitoring.

[0155] Fig.13 This is an example of a daily warning for microseismic monitoring. Combined with the mining location and microseismic event distribution in the daily report, the blue warning condition is triggered and a blue level warning is issued in the daily report, such as Fig.13 shown.

[0156] Fig.14 The diagram is a schematic diagram of the process of delineating the deep event intensive area. The early warning layer and its deep event monthly summary map are shown in Figure 14. The deep event intensive area can be delineated. On July 27, deep microseismic events began to occur in the working face about 100m away from the area. As the mining progressed, the deep events gradually increased. The mine took timely drainage measures and advanced at a uniform speed to ensure the safe mining of the working face.

[0157] It should be understood that the order of execution of the steps in the above embodiment does not necessarily mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiment of the present invention.

[0158] The following is an embodiment of the device of the present invention. For details not described in detail therein, reference may be made to the corresponding method embodiment described above.

[0159] Fig.15The schematic diagram of the structure of the all-time and space joint prevention and control device for repeated mining of water inrush risk in deep and close-range coal seams provided by an embodiment of the present invention is shown. For the convenience of explanation, only the part related to the embodiment of the present invention is shown, which is described in detail as follows:

[0160] like Fig.15 As shown, the full-time and space joint prevention and control device 2 for repeated mining of water inrush risk in deep and close-range coal seam groups includes:

[0161] Optimization module 21, used to optimize the working face tunnel layout plan through physical simulation and numerical simulation before mining, form a cutting eye and inclined double internal staggered layout mode, and perform floor tunnel layout;

[0162] The treatment module 22 is used to reduce the water pressure of the working face through regional treatment before mining, so as to increase the thickness of the water-proof layer and reduce the water inrush coefficient;

[0163] Monitoring module 23, used to monitor the time, space and intensity information of microseismic events in the area during mining, and determine the microseismic monitoring warning level;

[0164] The dewatering module 24 is used to observe the mine pressure value and hydrological information during mining and pay attention to their changes. At the same time, combined with the microseismic monitoring warning level and the deep event intensive area, it controls the mining speed and performs fixed-point dynamic dewatering and pressure reduction to reduce the water inrush coefficient of the working face.

[0165] In a possible implementation, the optimization module 21 is specifically used for:

[0166] Make a physical simulation model according to the similar scale with reference to the scale of the working face, and select the components of the physical simulation model according to the actual geological data of the mine;

[0167] Based on the physical simulation model, the roof was linearly pressurized in combination with the mining advancement time and the combined mechanical properties of the roof coal and rock mass. The bottom plate was pressurized with a spring to simulate the bottom plate water pressure, and a group of comparison schemes were compared. Among them, the comparison scheme was consistent with the dip alignment conditions, and the cut eye alignment and cut eye internal offset were compared.

[0168] In a possible implementation, the optimization module 21 is specifically used for:

[0169] Based on the borehole histogram of the monitoring working face, the physical and mechanical parameters of the surrounding rock and coal seam, a model of the movement law of the overburden rock during coal seam mining based on fluid-solid coupling simulation is established;

[0170] The orthogonal experimental design method was adopted, and three influencing factors, namely, cut-eye arrangement, dip arrangement and mining speed, were selected. Cut-eye alignment, cut-eye internal deviation, dip alignment, dip protrusion, dip internal deviation, slow mining, medium speed mining and fast mining were used as simulation factors and levels. Based on the overburden movement law model, the simulation factors and levels were combined and compared.

[0171] In a possible implementation, the governance module 22 is specifically used to:

[0172] Before mining, the thickness of the impermeable layer is increased through regional management, the water inrush coefficient in normal areas is controlled at 0.06MPa / m, and the water inrush coefficient in weak areas is controlled at 0.04MPa / m through water drainage.

[0173] In a possible implementation, the decongestion module 24 is specifically configured to:

[0174] When the working face is under pressure or the water volume change is greater than the preset water volume change threshold, the drainage time of the drainage borehole is controlled by the valve;

[0175] According to the mining conditions, water is released in the geological structure area, the microseismic deep event intensive area and the primary fracture zone;

[0176] The effect of depressurization is evaluated based on the changes in water level after depressurization and the changes in mine water inflow.

[0177] In a possible implementation, the monitoring module 23 is specifically used to:

[0178] If the daily amplitude of the bottom plate event is higher than the first preset threshold and lower than the second preset threshold, or microseismic events occur in the relatively water-rich thin limestone, the warning level is level 4;

[0179] If the daily amplitude of the bottom plate event exceeds the second preset threshold for 2 days within 7 days, or the main relatively water-rich thin limestone event occurs for 2 days within 7 days, or the Ordovician limestone event occurs, the warning level is level 3;

[0180] If the daily amplitude of the bottom plate events exceeds the third preset threshold for 5 days within 7 days, or the main relatively water-rich thin-layer limestone events occur for 5 days within 7 days, or the Ordovician limestone events occur for 3 days within 7 days, or the bottom plate microseismic events near the mining line are clustered in an up-and-down manner, the warning level is level 2;

[0181] If the Level 2 warning occurs for three consecutive days and an Aohui event occurs for three consecutive days, the warning level will be Level 1;

[0182] Based on the microseismic monitoring warning level and the deep event intensive area, the mining speed control and fixed-point dynamic drainage and pressure reduction are carried out, including:

[0183] The pressure intensity is determined based on the frequency change rate of microseismic events and the energy index, and prevention and control measures corresponding to the pressure intensity are taken; among them, the prevention and control measures include adjusting support measures, speed control and water pressure control.

[0184] In a possible implementation, the decongestion module 24 is specifically configured to:

[0185] The mining speed in deep event-intensive areas is controlled at 1.2 to 2 times the normal mining speed.

[0186] The embodiment of the present invention realizes mine pressure control by analyzing important parameters such as pressure step distance and floor damage depth through simulation data, and arranges floor lanes; realizes water pressure management through dynamic drainage and pressure reduction, regional governance and other measures; analyzes the spatiotemporal evolution of events in combination with indicators such as the frequency and depth of microseismic events, and takes different measures according to early warning to drain water or reduce the concentration of mine pressure. Dynamic joint control is achieved through the integration of mine pressure, water pressure, and microseismic monitoring and early warning, which runs through the entire period before mining and mining, reduces the risk of water inrush, and ensures safe mining of the working face.

[0187] Fig.16 is a schematic diagram of a terminal provided by an embodiment of the present invention. Fig.16 As shown, the terminal 3 of this embodiment includes: a processor 30, a memory 31, and a computer program 32 stored in the memory 31 and executable on the processor 30. When the processor 30 executes the computer program 32, the steps in the above-mentioned embodiments of the method for joint prevention and control of water inrush risk caused by repeated mining of each deep and close-range coal seam group in all time and space are implemented, for example Figure 1 Alternatively, when the processor 30 executes the computer program 32, the functions of each module / unit in the above-mentioned device embodiments are realized, for example Fig.15 Functions of the modules / units 21 to 24 are shown.

[0188] Exemplarily, the computer program 32 may be divided into one or more modules / units, which are stored in the memory 31 and executed by the processor 30 to implement the present invention. The one or more modules / units may be a series of computer program instruction segments capable of implementing specific functions, which are used to describe the execution process of the computer program 32 in the terminal 3. For example, the computer program 32 may be divided into Fig.15 Modules / units 21 to 24 are shown.

[0189] The terminal 3 may be a computing device such as a desktop computer, a notebook, a PDA, or a cloud server. The terminal 3 may include, but is not limited to, a processor 30 and a memory 31. Those skilled in the art will appreciate that Fig.16 It is only an example of terminal 3 and does not constitute a limitation on terminal 3. It may include more or fewer components than shown in the figure, or a combination of certain components, or different components. For example, the terminal may also include input and output devices, network access devices, buses, etc.

[0190] The processor 30 may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor, etc.

[0191] The memory 31 may be an internal storage unit of the terminal 3, such as a hard disk or memory of the terminal 3. The memory 31 may also be an external storage device of the terminal 3, such as a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, etc. equipped on the terminal 3. Further, the memory 31 may also include both an internal storage unit and an external storage device of the terminal 3. The memory 31 is used to store the computer program and other programs and data required by the terminal. The memory 31 may also be used to temporarily store data that has been output or is to be output.

[0192] The technicians in the relevant field can clearly understand that for the convenience and simplicity of description, only the division of the above-mentioned functional units and modules is used as an example for illustration. In practical applications, the above-mentioned function allocation can be completed by different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiment can be integrated in a processing unit, or each unit can exist physically separately, or two or more units can be integrated in one unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of software functional units. In addition, the specific names of the functional units and modules are only for the convenience of distinguishing each other, and are not used to limit the scope of protection of this application. The specific working process of the units and modules in the above-mentioned system can refer to the corresponding process in the aforementioned method embodiment, which will not be repeated here.

[0193] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0194] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present invention.

[0195] In the embodiments provided by the present invention, it should be understood that the disclosed devices / terminals and methods can be implemented in other ways. For example, the device / terminal embodiments described above are only schematic. For example, the division of the modules or units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0196] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0197] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0198] If the integrated module / unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the present invention implements all or part of the processes in the above-mentioned embodiment method, and can also be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a computer-readable storage medium. When the computer program is executed by the processor, it can implement the steps of the above-mentioned embodiments of the method for joint prevention and control of the risk of water inrush in the full time and space of each deep and close-range coal seam group repeated mining. Among them, the computer program includes computer program code, and the computer program code can be in the form of source code, object code, executable file or some intermediate form. The computer-readable medium may include: any entity or device that can carry the computer program code, recording medium, U disk, mobile hard disk, disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electric carrier signal, telecommunication signal and software distribution medium. It should be noted that the content contained in the computer-readable medium can be appropriately increased or decreased according to the requirements of legislation and patent practices in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practices, computer-readable media does not include electrical carrier signals and telecommunication signals.

[0199] The embodiments described above are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such 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, and should all be included in the protection scope of the present invention.

Claims

1. A method for joint prevention and control of water inrush risk caused by repeated mining of deep and close-range coal seams in all time and space, characterized in that: include: Before mining, the working face tunnel layout plan is optimized through physical simulation and numerical simulation to form a cutting eye and inclined double internal staggered layout, and the floor tunnel layout is carried out; Before mining, the thickness of the aquiclude can be increased through regional management to reduce the water inrush coefficient; During mining, the time, space and intensity information of microseismic events in the monitoring area are monitored, and the microseismic monitoring warning level is determined; During mining, the mine pressure value and hydrological information are observed and their changes are paid attention to. At the same time, combined with the microseismic monitoring warning level and deep event-intensive areas, the mining speed is controlled and the fixed-point dynamic drainage and pressure reduction are carried out to reduce the water inrush coefficient of the working face.

2. The full-time and space joint prevention and control method for repeated mining of water inrush risk in deep and close-range coal seams according to claim 1 is characterized in that: Optimize the working face tunnel layout plan through physical simulation before mining, including: A physical simulation model is prepared according to a similar scale with reference to the scale of the working face, and components constituting the physical simulation model are selected according to actual geological data of the mine; Based on the physical simulation model, the roof is linearly pressurized in combination with the mining advancement time and the combined mechanical properties of the roof coal and rock mass, and the bottom plate is pressurized with a spring to simulate the bottom plate water pressure, and a group of comparison schemes are compared; among them, the comparison scheme is consistent with the dip alignment conditions, and the cut eye alignment and cut eye internal offset are compared.

3. The full-time and space joint prevention and control method for repeated mining of water inrush risk in deep and close-range coal seams according to claim 1 is characterized in that: Before mining, the layout of the working face tunnels is optimized through numerical simulation, including: Based on the borehole histogram of the monitoring working face, the physical and mechanical parameters of the surrounding rock and coal seam, a model of the movement law of the overburden rock during coal seam mining based on fluid-solid coupling simulation is established; The orthogonal experimental design method was adopted, and three influencing factors, namely, cut-eye arrangement, dip arrangement and mining speed, were selected. Cut-eye alignment, cut-eye internal deviation, dip alignment, dip protrusion, dip internal deviation, slow mining, medium-speed mining and fast mining were used as simulation factors and levels. Based on the overburden movement law model, the simulation factors and levels were combined and compared.

4. The full-time and space joint prevention and control method for repeated mining of water inrush risk in deep and close-range coal seams according to claim 1 is characterized in that: The method of increasing the thickness of the aquiclude by regional treatment before mining to reduce the water inrush coefficient includes: Before mining, the thickness of the impermeable layer is increased through regional management, the water inrush coefficient in normal areas is controlled at 0.06MPa / m, and the water inrush coefficient in weak areas is controlled at 0.04MPa / m through water drainage.

5. The full-time and space joint prevention and control method for repeated mining of water inrush risk in deep and close-range coal seams according to claim 1 is characterized in that: The fixed-point dynamic hydrophobic pressure reduction comprises: When the working face is under pressure or the water volume change is greater than the preset water volume change threshold, the drainage time of the drainage borehole is controlled by the valve; According to the mining conditions, water is released in the geological structure area, the microseismic deep event intensive area and the primary fracture zone; The effect of depressurization is evaluated based on the changes in water level after depressurization and the changes in mine water inflow.

6. The full-time and space joint prevention and control method for repeated mining of water inrush risk in deep and close-range coal seams according to claim 1 is characterized in that: Determining the microseismic monitoring warning level includes: If the daily amplitude of the bottom plate event is higher than the first preset threshold and lower than the second preset threshold, or microseismic events occur in the relatively water-rich thin limestone, the warning level is level 4; If the daily amplitude of the bottom plate event exceeds the second preset threshold for 2 days within 7 days, or the main relatively water-rich thin limestone event occurs for 2 days within 7 days, or the Ordovician limestone event occurs, the warning level is level 3; If the daily amplitude of the bottom plate events exceeds the third preset threshold for 5 days within 7 days, or the main relatively water-rich thin-layer limestone events occur for 5 days within 7 days, or the Ordovician limestone events occur for 3 days within 7 days, or the bottom plate microseismic events near the mining line are clustered in an up-and-down manner, the warning level is level 2; If the Level 2 warning occurs for three consecutive days and an Aohui event occurs for three consecutive days, the warning level will be Level 1; The method of controlling the mining speed and performing fixed-point dynamic water drainage and pressure reduction based on the microseismic monitoring warning level and the deep event intensive area also includes: The pressure intensity is determined based on the frequency change rate of microseismic events and the energy index, and prevention and control measures corresponding to the pressure intensity are taken; wherein the prevention and control measures include adjusting support measures, speed control and water pressure control.

7. The full-time and space joint prevention and control method for repeated mining of water inrush risk in deep and close-range coal seams according to claim 1 is characterized in that: The pushing and mining speed control comprises: The mining speed in deep event-intensive areas is controlled at 1.2 to 2 times the normal mining speed.

8. A full-time and space joint prevention and control device for repeated mining of water inrush risk in deep and close-range coal seams, characterized in that: include: The optimization module is used to optimize the layout of the working face tunnels through physical simulation and numerical simulation before mining, form the layout of cutting eyes and inclined double internal staggering, and arrange the floor tunnels; The treatment module is used to increase the thickness of the aquiclude through regional treatment before mining to reduce the water inrush coefficient; The monitoring module is used to monitor the time, space and intensity information of microseismic events in the mining area and determine the microseismic monitoring warning level; The dewatering module is used to observe the mine pressure value and hydrological information during mining and pay attention to their changes. At the same time, combined with the microseismic monitoring warning level and deep event intensive areas, it controls the mining speed and performs fixed-point dynamic dewatering and pressure reduction to reduce the water inrush coefficient of the working face.

9. A terminal 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 computer program, the steps of the method according to any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the steps of the method as claimed in any one of claims 1 to 7 are implemented.

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