Coal mine water inrush deep ex-situ dredging and restoring method and system

Abstract

The invention aims to provide a coal mine water inrush body deep ex-situ dredging and restoring method and system, and belongs to the technical field of coal mine water disaster prevention and control. The system comprises a water inrush body recognition module, a drainage depressurization system, a closed pipeline collection system, a storage stratum screening and well design module, a high-pressure storage ectopic dredging system and a safety monitoring system. According to the method, the water inrush body is identified by finely evaluating the hydrogeological conditions, the optimal hydrogeological parameters are obtained by using the parameter inversion model and the particle swarm optimization, and drainage and pressure reduction are guided; a reservoir capacity grade dynamic evaluation system is established, a deep suitable stratum is screened, collected mine water is stored back to the deep part by using high-pressure equipment, and full-period safety monitoring is performed in combination with a multi-source data fusion early warning model. The strategic reserve of the mine water depth is achieved, the underground water ecology is effectively maintained, and the treatment cost and the safety risk are remarkably reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of coal mine water disaster prevention, and particularly relates to a coal mine water inrush deep part off-site dredging and storage method and system. BACKGROUND

[0002] The Ordos Basin is one of the main coal bases in China, and it bears the important responsibility of national energy supply safety. The coal production reached 1.36 billion tons in 2023. However, due to the special hydrogeological and engineering geological structure in the western region, a large amount of high-salt mine water is often produced from the roof during coal mining, with a production of more than 2.9 cubic meters per ton of coal. With the increasing depth and intensity of mining, the safety risk of water disaster is increasingly prominent, and the contradiction between coal and water development is intensified. The safe disposal of coal water inrush bodies has become a key problem faced by high-intensity mining and ecological environment protection.

[0003] Currently, the treatment of coal mine water inrush bodies mainly relies on the traditional lifting and surface treatment mode. The mine water needs to be lifted from the underground to the ground first, and then purified and discharged or utilized after a complex treatment process. This mode has many problems. On the one hand, the cost of mine water lifting is as high as 2.5 yuan / ton, and the treatment cost of high-salt mine water is as high as 18 yuan / ton, which brings a huge economic burden to enterprises. On the other hand, the discharge of a large amount of mine water has a continuous impact on the regional groundwater ecological environment. Under the background of increasingly strict ecological control, the discharge of mine water is facing more and more restrictions. In addition, the traditional treatment mode cannot fundamentally solve the water inrush threat of mining and excavation faces, and the mine water after pressure reduction still needs to be lifted and treated, which fails to realize the in-situ absorption and deep storage of water inrush bodies.

[0004] The existing technology lacks a systematic deep part off-site dredging and storage scheme for water inrush bodies. There is a lack of fine evaluation means in the identification of water inrush bodies, making it difficult to accurately determine the spatial distribution and water-rich nature of the main water-filled aquifer. There is a lack of scientific drilling layout method and water level monitoring control system in the water pressure reduction process. There are problems such as insufficient airtightness and unreasonable pipeline setting in the process of mine water collection and transportation. There is a lack of systematic geological evaluation standard and scientific reservoir capacity calculation method in the selection of storage strata. There is a lack of effective pressure and flow regulation system and long-term operation guarantee measures in the implementation process of high-pressure storage. There is a lack of a three-dimensional monitoring and early warning system for deep storage in safety monitoring. These problems make it difficult to achieve safe, economic, and environmentally friendly deep part off-site dredging and storage of coal mine water inrush bodies, which restricts the sustainable development of coal mining enterprises.

[0005] Therefore, it is urgent to develop a systematic coal mine water inrush deep allopatry dredging and storage technical scheme, realize the whole process technical integration from water inrush body identification, water drainage pressure reduction, closed collection, back storage stratum screening, high pressure back storage to safety monitoring, effectively reduce the mine water treatment cost, reduce the influence of mine water discharge on ecological environment, reduce the water inrush risk of mining working face, and guarantee the safety production of coal mine. SUMMARY

[0006] The purpose of the present application is to overcome the deficiencies in the prior art, provide a coal mine water inrush body deep allopatry dredging and storage method and system, collect water sources by closed pipeline, and allopatry dredge mine water to the screened deep stratum by high pressure water injection pump for back storage, finally realize the safe back storage of coal mine water inrush body by establishing an up-down three-dimensional safety monitoring system, and reduce the treatment cost and discharge risk.

[0007] To achieve the above purpose, the first aspect of the present application provides a coal mine water inrush body deep allopatry dredging and storage method, comprising the following steps:

[0008] Step S1, water inrush body identification, according to the influence height of the caving zone and the water flowing fractured zone after the coal seam is mined, the development height of the caving zone and the water flowing fractured zone is determined by drilling exploration, water pressure test, network parallel electric method monitoring and drilling peeping method, the hydrogeological conditions of the mining area are evaluated, the spatial distribution and water abundance of the main water-filled aquifer of the coal mine are found out, the source of the water inrush body is determined according to the water chemical composition of the main water-filled body, and the mine water inflow is calculated according to the hydrogeological parameters;

[0009] Step S2, water drainage pressure reduction, according to the water inrush body and water-rich area identified in step S1, drill fields are arranged along the two roadways of the working face, water drainage boreholes are constructed according to the grid distance combined with the estimated water inflow of the water-rich area, the changes of underground water level and water quantity are monitored through the installation of flow meters and water pressure gauges, the water drainage boreholes are started according to the water level change and drainage system arrangement, and water inrush body water level control is realized;

[0010] Step S3, closed collection, the water drainage boreholes are connected by a closed collection pipeline to collect the underground water generated by water drainage pressure reduction, the closed collection pipeline is controlled and adjusted in real time through valves, flow meters and water quality monitoring sensors to meet the water quantity and water quality requirements of high pressure back storage;

[0011] Step S4, back storage stratum screening and back storage well setting, the system collects geological stratum data, determines the stratum system characteristics, delimits the regional structure target area by using gravity and magnetic anomalies, excludes strata with mineral resources endowment, establishes the structure stress field and finds out the brittle stratum, quantitatively determines the supply runoff discharge conditions, water quality characteristics and boundaries of hydrogeology, screens the fractured sandstone stratum or karst limestone stratum, determines the back storage stratum, and sets the back storage well to build vertical channels or directional channels;

[0012] Step S5, high-pressure storage and diversion, the mine water collected in step S3 is temporarily stored in a storage pool, the water quality is monitored through an online water quality sensor and a temperature sensor, the water is transported to a water injection pump through a water inlet pump, the frequency of the plunger of the water injection pump is set, the pressure and flow are connected to the storage well for high-pressure storage, the mine water is injected into the deep stratum through the storage well, a signal mutual feedback adjustment system is formed through an online flow sensor and a water pressure sensor, the working frequency of the water injection pump is adjusted according to the changes of the pressure and flow, and the mine water is diverted in a high-pressure storage and diversion manner away from the site;

[0013] Step S6, safety monitoring, after the safety risk and roof and floor water inrush risk of the project are evaluated, a plurality of monitoring and early warning methods such as microseismic, electrical method and stress are established; microseismic sensors and electrical method sensors are arranged along the ground and the underground roadway of the coal mine to receive signals from the rock rupture and water enrichment change of the storage layer, armored optical fiber sensors are laid in the storage well and the monitoring well to collect temperature signals and stress and strain signals, the collected data are processed through multi-source heterogeneous fusion, and a single-factor or multi-factor early warning model is constructed.

[0014] Further, in the water inrush body identification module in step S1, an inversion model is constructed to calculate an optimal water conductivity T and a water storage coefficient S:

[0015] ,

[0016] In the formula, N is the number of observation time series data points; is the measured water level drawdown at i moment; Q is the water inflow in the current water diversion experiment process; T is the water conductivity to be inverted; S is the water storage coefficient to be inverted; is a well function; r is the distance from the calculation point to the water outlet well; is a prior water conductivity; is a prior water storage coefficient; is the observation time at i moment; is a regularization term, wherein is a regularization parameter.

[0017] Further, the parameter inversion model searches for minimization of the objective function through a particle swarm optimization algorithm PSO, and the particle swarm optimization algorithm specifically operates as follows:

[0018] The particle swarm size NP is determined, and the value range of NP is [20, 100];

[0019] The search range of the water conductivity T and the water storage coefficient S is set according to the hydrogeological prior knowledge obtained through exploration of the mining area;

[0020] The inertia weight , the initial value range is [0.9, 1.2], the final value range is [0.4, 0.6], the learning factor , the learning factor , the learning factor

[0021] The initial position of each particle is taken as its individual historical optimal position P, and the position that makes The minimum position is selected as the group historical optimal position G.

[0022] The particle velocity and position are updated, and the individual optimal is selected.

[0023] The group optimal is updated: the position with the optimal fitness is selected from all the updated individual optimal positions P as the group optimal position G. The position of each particle j Is updated according to the following formula:

[0024] ,

[0025] ,

[0026] In the formula, Is the velocity of particle j; Is the position of particle j; Is the inertia weight; Is the learning factor; Is a random number between 0 and 1; k is the iteration number; Is the individual historical optimal position of particle j; Is the group historical optimal position.

[0027] Further, the water level drawdown of the observation point in step S2 is calculated using the optimal transmissibility T and storage coefficient S calculated by the parameter inversion model according to claims 2 and 3:

[0028] ,

[0029] In the formula: s is the water level drawdown of the observation point; Q is the flow of the water outlet; T is the transmissibility; t is the time from the start of water release to the calculation time; r is the distance from the calculation point to the water release well; S is the storage coefficient of the aquifer.

[0030] Further, the closed collection pipeline in step S3 has airtightness and pressure resistance, and the closed collection pipeline is arranged considering the structure of the coal mine underground aquifer and the position of the pre-drainage device, so as to ensure that the pipeline arrangement is reasonable and the path is unobstructed.

[0031] Further, characterized in that the optimal transmissibility T and storage coefficient S calculated by the parameter inversion model are used to predict the mine water inflow under the drainage time t and water level drawdown s:

[0032] ,

[0033] in: In the formula, Q is the predicted inflow; T is the hydraulic conductivity; and s is the drawdown at the observation point. denoted as the Tays well function; u is the parameter of the Tays well function; r is the distance from the calculation point to the discharge well; S is the water storage coefficient of the aquifer; t is the time from the start of water discharge to the calculation time.

[0034] Furthermore, in the high-pressure recharge and off-site diversion system described in step S5, a dynamic evaluation system for reservoir capacity levels is established. Specifically, three reservoir capacity evaluation indicators are determined for level evaluation, including: theoretical reservoir capacity, effective reservoir capacity, and actual water storage volume. The calculation method for the reservoir capacity evaluation indicators is as follows:

[0035] Theoretical storage capacity calculation formula:

[0036] ,

[0037] In the formula, A represents the theoretical reservoir capacity; A represents the reservoir area; H represents the reservoir thickness. Effective porosity; This is the fracture development coefficient.

[0038] Effective storage capacity calculation formula:

[0039] ,

[0040] In the formula, For effective storage capacity; The theoretical reservoir capacity is T; T is the optimal hydraulic conductivity obtained from parameter inversion calculation. The maximum hydraulic conductivity in the region; Actual water injection pressure; This refers to the formation fracturing pressure; This is the hydraulic connectivity coefficient.

[0041] Formula for calculating actual water storage:

[0042] ,

[0043] In the formula, This represents the actual water storage capacity. This refers to the water injection rate; This refers to the vertical leakage rate; t represents the lateral loss rate; t represents the injection time.

[0044] Furthermore, the criteria for determining the storage capacity level are as follows:

[0045] The first level reservoir capacity is set as a high-quality water storage layer, and the following conditions are met simultaneously: , , , microseismic event frequency times / day;

[0046] The second level reservoir capacity is set as a medium water storage layer, and any one of the following conditions is met: , , , microseismic event frequency 5-15 times / day;

[0047] The third level reservoir capacity is set as a limited water storage layer, and any one of the following conditions is met: , , , microseismic event frequency > 15 times / day, and formation pressure stability coefficient < 0.7.

[0048] Further, the early warning model in step S6 is a single-factor early warning model or a multi-factor early warning model, and the early warning information is provided to the coal mine user through the early warning model.

[0049] In a second aspect, the present application also provides a coal mine water inrush deep heterotopic dredging and storage system for executing the coal mine water inrush deep heterotopic dredging and storage method as described above, comprising:

[0050] A water inrush body identification module is used to finely evaluate the hydrogeological conditions of the mining area according to the caving zone and the water flowing fractured zone after the coal seam is mined, to find out the spatial distribution and water abundance of the main water filling aquifer of the coal mine, to determine the source of the water inrush body, to calculate the mine water inflow, and to build a parameter inversion model and calculate the optimal water conducting coefficient T and the water storage coefficient S through a particle swarm optimization algorithm;

[0051] A water drainage and pressure reduction system is used to drain and reduce the pressure of the water inrush body, comprising a drilling field and a water drainage borehole arranged along the two roadways of the working face, a flowmeter and a water pressure gauge installed on the water drainage borehole, and the T and S coefficients calculated by the inversion model are used to predict the mine water inflow and calculate the water level drawdown of the observation point;

[0052] A water drainage and discharge sealed pipeline collection system is used to collect the underground water generated by the water drainage and pressure reduction and transport it to the high-pressure storage equipment, comprising a sealed collection pipeline connected to the water drainage borehole, and a valve, a flowmeter and a water quality monitoring sensor arranged on the sealed collection pipeline;

[0053] A back storage stratum screening and well setting module is used to screen the back storage stratum and set the back storage well, and the back storage well is a vertical channel or a directional channel;

[0054] The high-pressure back storage ectopic drainage system for injecting mine water into deep strata comprises a storage pool, an online water quality sensor, a temperature sensor, a water inlet pump, a water injection pump, an online flow sensor and a water pressure sensor, the water injection pump is connected with the back storage well, and a reservoir capacity level dynamic evaluation system is established.

[0055] The safety monitoring and early warning system is used for safety monitoring of the back storage process, comprises microseismic sensors and electrical method sensors arranged on the ground and underground mine roadway, and armored optical fiber sensors laid in the back storage well and the monitoring well, and a single factor or multi-factor early warning model is built.

[0056] Compared with the prior art, the present application has the following beneficial effects:

[0057] (1) The present application proposes a coal mine water inrush deep ectopic drainage and back storage method, which integrates six steps of water inrush body identification, water drainage and pressure reduction, closed collection, back storage stratum screening, high-pressure back storage ectopic drainage and safety monitoring, and forms a complete closed-loop technical solution. The method uses the "two-zone" wave propagation height evaluation and water chemical analysis to finely identify the source and water enrichment of the water inrush body, sets up a drilling field along the two roadways of the working face for targeted water drainage and pressure reduction, and screens suitable deep fracture type sandstone or karst type limestone strata as back storage layers. The mine water is safely injected into the deep strata by using a high-pressure water injection pump and a signal mutual feedback adjustment system, which not only solves the problem of coal mine water inrush body treatment, but also effectively maintains the underground water ecological environment and reduces the risk of secondary geological disasters.

[0058] (2) The present application significantly improves the accuracy of hydrogeological parameter acquisition and the scientificity of water drainage engineering by building a parameter inversion model and combining a particle swarm optimization algorithm. The method establishes a target function with measured water level drawdown and water inflow as input, introduces a regularization term, and uses the linear decreasing inertia weight and learning factor in the particle swarm algorithm to dynamically search for the global optimal transmissibility coefficient T and storage coefficient S, avoiding the error of empirical assignment. Based on the accurate parameters obtained by inversion, the present application can accurately predict the mine water inflow under different drainage times and water level drawdowns using the Theis well function, and calculate the water level drawdown of the observation point, providing reliable quantitative basis for the opening and closing control of the water drainage borehole and the capacity configuration of the mine drainage system.

[0059] (3) This invention innovatively establishes a dynamic evaluation system for reservoir capacity levels, overcoming the limitations of traditional static reservoir capacity calculation and achieving accurate assessment of the water storage capacity of deep strata. This system quantifies three core indicators: theoretical reservoir capacity, effective reservoir capacity, and actual water storage. It comprehensively considers key factors such as reservoir area, effective porosity, fracture development coefficient, and the ratio of actual injection pressure to formation fracturing pressure. Based on the ratio relationships between indicators and the frequency of microseismic events, the reservoir strata are divided into three levels: high-quality reservoir, medium-quality reservoir, and limited reservoir. This multi-factor weighted quantitative judgment standard guides on-site personnel to maximize the utilization of reservoir capacity while ensuring stable formation pressure, achieving a balance between injection efficiency and geological safety.

[0060] (4) This invention ensures the safety of the entire project lifecycle through a high-standard closed-loop transportation and multi-source early warning mechanism. The closed-loop drainage collection system has excellent airtightness and pressure resistance. Combined with the real-time adjustment of valves, flow meters and water quality monitoring sensors, it effectively prevents the risk of leakage during the high-pressure water transportation process. At the same time, the safety monitoring link integrates multi-source heterogeneous data such as microseismic, electrical resistivity, stress-strain and temperature data from the ground and underground to construct a single-factor or multi-factor early warning model. This model can capture the signals of rock fracturing and water-bearing changes in the reservoir in real time, promptly detect signs of instability in the overburden structure, and provide real-time and accurate early warning information for safe coal mine production.

[0061] (5) This invention provides a deep ex-situ drainage and storage system for coal mine water inrush bodies that integrates water inrush body identification, drainage and pressure reduction, pipeline collection, formation screening, high-pressure storage and safety monitoring, achieving significant economic and social benefits. This system transforms the traditional mine water discharge mode into a deep strategic reserve mode, greatly reducing treatment costs. Calculated based on a single well service period of 5 years, it can cumulatively save approximately RMB 86.5 million in mine water treatment costs, reducing the cost per ton of mine water treatment from approximately RMB 20.5 to RMB 2 to 3, while reducing the amount of mine water discharged by approximately 5 million cubic meters. While ensuring safe production at the mining face, it achieves efficient utilization of water resources and low-cost green management. Attached Figure Description

[0062] The accompanying drawings, which form part of this specification, illustrate embodiments of the invention and, together with the specification, serve to explain the principles of the invention.

[0063] The invention will be more clearly understood with reference to the accompanying drawings and the following detailed description, wherein:

[0064] Figure 1 This is a flowchart of the deep ex-situ diversion and storage method for coal mine water inrush bodies provided in the embodiments of the present invention;

[0065] Figure 2is a water inrush body identification schematic diagram provided by the embodiment of the present application;

[0066] Figure 3 is a water inrush body identification schematic diagram provided by the embodiment of the present application;

[0067] Figure 4 is a water inrush body identification schematic diagram provided by the embodiment of the present application;

[0068] Figure 5 is a water inrush body identification schematic diagram provided by the embodiment of the present application;

[0069] Figure 6 is a water inrush body identification schematic diagram provided by the embodiment of the present application;

[0070] Figure 7 is a water inrush body identification schematic diagram provided by the embodiment of the present application; DETAILED DESCRIPTION

[0071] The technical solutions of the present application will be described in detail below with the help of the accompanying drawings and specific embodiments. It should be understood that the specific features in the embodiments and the embodiments of the present application are detailed descriptions of the technical solutions of the present application, and are not limitations of the technical solutions of the present application. In the case of no conflict, the technical features in the embodiments and the embodiments of the present application can be combined with each other. The following embodiments are only used to more clearly illustrate the technical solutions of the present application, and cannot limit the protection scope of the present application.

[0072] The term "and / or" in this paper is only a description of the association relationship between the associated objects, which means that there can be three kinds of relationships, for example, A and / or B, which can represent the existence of A alone, the existence of A and B at the same time, and the existence of B alone. In addition, the character " / " in this paper generally represents that the associated objects before and after are a kind of "or" relationship.

[0073] As shown in Figure 1 The present embodiment provides a coal mine water inrush body deep heterotopic dredging and storage method, which comprises the following steps:

[0074] Step S1, water inrush body identification: as Figure 2As shown, the present application is affected by the hydrogeological and engineering geological structure of coal mines in the western region, and first needs to finely evaluate the hydrogeological conditions of the mining area according to the influence height of the "two zones" after coal seam mining, that is, the caving zone and the water-conducting fractured zone. This process uses drilling exploration, water pressure test, network parallel electric method monitoring and borehole peeping and other methods to determine the actual development height of the "two zones". Subsequently, the source of the water inrush body is accurately distinguished according to the water chemical composition of the main water filling body, and the spatial distribution and water abundance of the main water filling aquifer are found out. On this basis, the present application also constructs a parameter inversion model, and uses the particle swarm optimization algorithm PSO to dynamically solve the optimal water conductivity coefficient T and water storage coefficient S, and then calculates the normal water inflow of the mine according to these hydrogeological parameters. Among them, the constructed parameter inversion model is used to calculate the optimal water conductivity coefficient T and water storage coefficient S, and the objective function is

[0075] ,

[0076] In the formula, N is the number of observation time series data points; is the measured water level drawdown at i moment; is the well function; Q is the water inflow in the current water drainage experiment process; is the prior water conductivity coefficient; is the prior water storage coefficient; is the regularization term, wherein is the regularization parameter, . The parameter inversion model searches for the minimum of the objective function by the particle swarm optimization algorithm PSO, and in the algorithm, the objective function is directly taken as the fitness function, and the smaller the value is, the better the particle position is. The specific operation steps of the particle swarm optimization algorithm are as follows:

[0077] 1. Determine the particle swarm size NP, and the value range of NP is [20, 100];

[0078] 2. Set the search range of the water conductivity coefficient T and the water storage coefficient S according to the hydrogeological prior knowledge obtained by the mine exploration;

[0079] 3. Set the inertia weight using the linear decreasing strategy, and the initial value range is [0.9, 1.2], and the final value range is [0.4, 0.6]. The value range of the learning factor , is [1.5, 2.0];

[0080] 4. Take the initial position of each particle as its individual historical optimal position P, and select the position that makes minimum from all P as the group historical optimal position G;

[0081] 5. Update the particle velocity and position, select the individual optimal;

[0082] 6. Update the group optimal: select the optimal position of fitness from all updated individual optimal positions P as the group optimal position G. The position of each particle j is updated according to the following formula:

[0083] ,

[0084] ,

[0085] wherein, , is the velocity and position of particle j, and the position is a candidate value of a set [T, S]; is the inertia weight updated to the Kth generation; , is a learning factor; , is a random number between 0 and 1. When the group optimal position G converges, the algorithm is terminated, and the final group optimal position G is output as the optimal hydraulic conductivity T and storage coefficient S obtained by parameter inversion.

[0086] Step S2, hydrophobic pressure reduction: according to the water inrush body position and water-rich area identified in step S1, drill fields are arranged along the two roadways of the working face, as shown in Figure 3 , and combined with the estimated water yield of the water-rich area, drainage holes are constructed according to a certain grid distance, and the structure of the drainage pressure reduction drill hole is determined according to the estimated drainage amount, so as to drain the water in the water inrush body of the roof or floor of the working face. These drill holes are mainly concentrated in the area where the water inrush body is located and the water level is high. By installing flow meters and water pressure gauges, the changes of underground water level and water yield are monitored in real time, and according to the changes of water level and the overall arrangement of the drainage system, the corresponding drainage drill holes are reasonably started, and finally the safe control of the water inrush body water level is realized, and the threat of water disaster is slowed down, as shown in Figure 3 the underground water funnel. The water level drawdown of the observation point in the drainage process is calculated by the optimal hydraulic conductivity T and storage coefficient S calculated by the parameter inversion model, and the formula is

[0087] ,

[0088] wherein: s is the water level drawdown of the observation point; Q is the flow of the drainage hole; T is the hydraulic conductivity; t is the time from the start of drainage to the calculation time; r is the distance from the calculation point to the drainage well; S is the storage coefficient of the aquifer.

[0089] Step S3, closed collection: as shown in Figure 4As shown, the drainage closed pipeline collection system with certain airtightness and pressure resistance is connected with each drainage borehole to collect and transport the underground water generated in the drainage depressurization process to the high-pressure storage equipment, thereby playing a role of water guide and water flow transmission. The pipeline system needs to consider the structure of the coal mine underground aquifer and the position of the pre-drainage device to ensure that the pipeline arrangement is reasonable and the path is unobstructed. The pipeline is also equipped with valves, flow meters and water quality monitoring sensors for reasonable control of the opening and closing of the drainage depressurization and real-time adjustment to ensure that the water quantity and water quality collected meet the requirements of subsequent high-pressure storage. At the same time, the optimal water guide coefficient T and the storage coefficient S calculated by the parameter inversion model are used to predict the mine water inflow under the drainage time t and water level drawdown s, and the formula is

[0090] wherein ,

[0091] In the formula, Q is the predicted water inflow; is the Thies well function, that is, the in the inversion model.

[0092] Step S4, selection of storage stratum and setting of storage well: when selecting the storage target stratum, the following steps need to be taken: 1. collect geological stratum data; 2. determine the characteristics of the stratum system; 3. use gravity and magnetic anomalies to delineate regional structures and grade “sweet spot” target areas; 4. exclude strata with mineral resources endowments; 5. establish a tectonic stress field and identify brittle strata; 6. quantitatively analyze hydrogeological recharge, runoff and discharge conditions, water quality characteristics and boundaries; 7. scientifically select suitable fractured sandstone strata or karst limestone strata as storage areas; and 8. comprehensively determine and optimize the storage stratum. After determining the stratum, the storage well engineering is designed and implemented according to the geological and hydrogeological structure of the mining area, as shown in Figure 5 The storage well, as a channel, can be a vertical channel or a directional channel, and its arrangement needs to consider the layout of the coal mine underground space and the safety production requirements. The design of the storage well will refer to the relevant well structure design requirements and specifications in the coal mine industry field.

[0093] Step S5, high-pressure storage and heterotopic drainage: as shown in Figure 6As shown, the mine water collected in step S3 is first temporarily stored in a storage tank, and online water quality sensors and temperature sensors are installed to monitor the water quality. Then, the water is pumped to the injection pump via an intake pump. The appropriate pressure and flow rate are selected by setting the injection pump plunger frequency, and the system is connected to a return storage well for high-pressure return storage. The injection pump uses the return storage well to inject the mine water into the deep formation under high pressure. The entire system is equipped with online flow sensors and water pressure sensors, forming a signal feedback regulation system that can automatically adjust the operating frequency of the injection pump according to real-time changes in pressure and flow. A key objective of this invention is to increase the permeability and storage capacity of the return storage formation through long-term hydraulic fracturing, achieving the expected return storage capacity. Simultaneously, the system establishes a dynamic evaluation system for storage capacity levels, using three indicators—theoretical storage capacity, effective storage capacity, and actual water storage—to dynamically assess the state of the reservoir. This system includes three storage capacity evaluation indicators, calculated as follows:

[0094] Theoretical storage capacity calculation formula:

[0095] ,

[0096] In the formula, A is the area of ​​the aquifer; H is the thickness of the aquifer. Effective porosity; This is the fracture development coefficient, before hydraulic fracturing. After hydraulic fracturing .

[0097] Effective storage capacity calculation formula:

[0098] ,

[0099] In the formula, The effective reservoir capacity is T; T is the optimal hydraulic conductivity obtained from parameter inversion calculation. The maximum hydraulic conductivity in the region, The closer the ratio is to 1, the better the water conductivity of the current formation; Actual water injection pressure; For formation fracture pressure, The closer the ratio is to 1, the greater the potential for water injection pressure is utilized and the higher the water injection efficiency. A ratio greater than 1 means there is a risk of inducing new cracks and causing overburden instability. The hydraulic connectivity coefficient is determined through a multi-hole pressure water test.

[0100] Formula for calculating actual water storage:

[0101] ,

[0102] In the formula, This refers to the water injection rate; This represents the vertical leakage rate; This represents lateral loss.

[0103] The criteria for determining the storage capacity level are as follows:

[0104] Level 1 reservoir capacity, i.e., high-quality aquifer: must meet the following conditions simultaneously: , , Microseismic event frequency Once / day;

[0105] Level 2 reservoir capacity, i.e., medium-sized reservoir: meets any of the following conditions: , , Microseismic events occur 5-15 times per day;

[0106] Level 3 reservoir capacity, i.e., finite water storage: meets any of the following conditions: , , Microseismic event frequency > 15 times / day, formation pressure stability coefficient < 0.7.

[0107] Step S6, Safety Monitoring: High-pressure backfilling significantly alters the hydrodynamic conditions of the backfill layer, forming high-pressure water mounds within the influence radius of the backfill well. Under the influence of high water pressure and mining disturbances, this can easily lead to instability of the overlying rock structure and induce secondary geological disasters. Therefore, after conducting an engineering safety risk assessment, if... Figure 7 As shown, a targeted three-dimensional safety monitoring system was established both above and below ground. This system deploys microseismic and electrical resistivity sensors along the surface and in underground mine roadways and working faces to receive signals of rock fracturing and changes in water content. Through the installation of data acquisition substations and data transmission lines, these signals are uniformly sent to a surface data processing station for in-depth analysis and real-time display, providing real-time safety monitoring information for the coal mine. Simultaneously, armored fiber optic sensors are laid in the storage and monitoring wells to collect signals such as temperature and stress-strain. These signals are then collected and processed to provide users with real-time monitoring information. Finally, the collected data undergoes multi-source heterogeneous fusion processing to construct single-factor or multi-factor early warning models, achieving safe high-pressure storage and providing early warning information to coal mine users.

[0108] As one embodiment, the present invention also provides a deep ex-situ diversion and storage system for coal mine water inrush bodies, used to execute any of the aforementioned deep ex-situ diversion and storage methods for coal mine water inrush bodies, comprising:

[0109] The water inrush body identification module is used to evaluate the hydrogeological conditions of the mining area in a high degree of detail based on the impact of the caving zone and water-conducting fracture zone after coal seam mining, identify the spatial distribution and water-bearing properties of the main water-bearing aquifers in the coal mine, determine the source of the water inrush body, calculate the mine water inflow, and construct a parameter inversion model and calculate the optimal water conductivity T and water storage coefficient S through the particle swarm optimization algorithm.

[0110] A hydrophobic pressure reduction system for hydrophobic pressure reduction of the water inrush body, comprising a drilling field and a water drainage borehole arranged along two roadways of a working face, and a flow meter and a water pressure meter installed on the water drainage borehole, and T and S coefficients are calculated by using an inversion model to predict the mine water inflow and calculate the water level drawdown of an observation point;

[0111] A drainage sealed pipeline collection system for collecting underground water generated by hydrophobic pressure reduction and conveying to a high-pressure storage device, comprising a sealed collection pipeline connected to the water drainage borehole, and a valve, a flow meter and a water quality monitoring sensor arranged on the sealed collection pipeline;

[0112] A storage stratum screening and well setting module for screening a storage stratum and setting a storage well, the storage well being a vertical channel or a directional channel;

[0113] A high-pressure storage ectopic drainage system for injecting mine water into a deep stratum, comprising a storage pool, an online water quality sensor, a temperature sensor, a water inlet pump, a water injection pump, an online flow sensor and a water pressure sensor, the water injection pump being connected to the storage well, and a reservoir capacity level dynamic evaluation system being established;

[0114] A safety monitoring and early warning system for safety monitoring of the storage process, comprising microseismic sensors and electrical method sensors arranged on the ground and in the underground roadway of the coal mine, and armored optical fiber sensors laid in the storage well and the monitoring well, and a single factor or multi-factor early warning model being constructed.

[0115] The energy-saving and emission-reducing benefit analysis of the present application is as follows: according to the general situation, the cost of lifting one ton of mine water is 2.5 yuan / ton, the cost of treating high-salt mine water is 18 yuan / ton, the construction cost of a single storage well is 8 million yuan, the storage equipment and monitoring equipment matched with the storage well are calculated as 3 million yuan, the depreciation of the storage equipment is calculated as 5 years, 10 million m3 of mine water is stored per year, the annual electricity cost is about 1 million yuan, and the service period is 5 years, so the first year saving is 10 million x (18+2.5)-80 million-6 million-10 million=109 million yuan; the second year, the third year, the fourth year and the fifth year each year save 10 million x (18+2.5)-6 million-10 million=189 million yuan, and the cumulative savings during the service period is 86.5 million yuan for a single well, and the treatment cost of mine water per ton is reduced from 20.5 yuan to 2-3 yuan. At the same time, 50 million m3 of mine water is reduced and converted into unconventional water resources for deep strategic reserve, and the risk of water inrush in mining and excavation working faces is reduced, and normal production of working faces is ensured.

[0116] The above merely describes the preferred embodiments of the present application, and it should be pointed out that, for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present application, and these improvements and modifications should also be considered as the protection scope of the present application.

Claims

1. A coal mine water inrush body deep part allochthonous dredging and storage method, characterized in that, The method comprises the following steps: Step S1, water inrush body identification, according to the wave height of the caving zone and the water flowing fractured zone after the coal seam is mined, the development height of the caving zone and the water flowing fractured zone is determined by drilling exploration, water pressure test, network parallel electric method monitoring and drilling peep method, the hydrogeological conditions of the mining area are evaluated, the spatial distribution and water abundance of the main water filling aquifer of the coal mine are found out, the source of the water inrush body is determined according to the water chemical composition of the main water filling body, and the mine water inflow is calculated according to the hydrogeological parameters; Step S2, water drainage and pressure reduction, according to the water inrush body and water-rich area identified in step S1, drill fields are arranged along the two roadways of the working face, water drainage and pressure reduction drill holes are constructed according to the grid distance combined with the estimated water inflow of the water-rich area, the change of underground water level and water quantity is monitored through the installation of flow meters and water pressure gauges, the water drainage and pressure reduction drill holes are started according to the change of water level and the drainage system, and water inrush body water level control is realized; Step S3, closed collection, the underground water generated by water drainage and pressure reduction is collected through the closed collection pipeline connected with the water drainage drill hole, the closed collection pipeline is controlled and adjusted in real time through valves, flow meters and water quality monitoring sensors to meet the water quantity and water quality requirements of high-pressure storage; Step S4, selection of storage stratum and setting of storage well, the system collects geological stratum data, determines the stratum system characteristics, delimits the regional structure target area by using gravity and magnetic anomalies, excludes strata with mineral resources endowment, establishes a structure stress field and finds out brittle strata, quantitatively determines the supply runoff discharge conditions, water quality characteristics and boundaries of hydrogeology, selects crack-type sandstone strata or karst-type limestone strata, determines the storage stratum, and sets up the storage well for building vertical channels or directional channels; Step S5, high-pressure storage and diversion, the mine water collected in step S3 is temporarily stored in a storage tank, the water quality is monitored through online water quality sensors and temperature sensors, the water is transported to a water injection pump through a water inlet pump, the plunger frequency of the water injection pump is set, the pressure and flow are connected with the storage well for high-pressure storage, the mine water is injected into deep strata through the storage well, an online flow sensor and a water pressure sensor form a signal mutual feedback adjustment system, the working frequency of the water injection pump is adjusted according to the change of pressure and flow, and mine water high-pressure storage and diversion are realized; Step S6, safety monitoring, after the safety risk and roof and floor water inrush risk of the project are evaluated, a plurality of monitoring and early warning methods such as microseism, electric method and stress are established; microseismic sensors and electric method sensors are arranged along the ground and the roadway in the coal mine to receive signals from the rock fracture and water abundance change of the storage layer, armored optical fiber sensors are laid in the storage well and the monitoring well to collect temperature signals and stress and strain signals, the collected data are processed through multi-source heterogeneous fusion, and a single-factor or multi-factor early warning model is constructed.

2. The coal mine water inrush body deep part allochthonous dredging and storage method according to claim 1, characterized in that, In the water inrush body identification module in step S1, a parameter inversion model is constructed to calculate the optimal water conductivity T and water storage coefficient S: ， In the formula, N represents the number of observation time series data points; is the measured water level drawdown at i moment; Q is the water inflow in the current water release experiment; T is the to-be-inverted transmissibility coefficient; S is the to-be-inverted storage coefficient; is the well function; r is the distance from the calculation point to the water release well; is the prior transmissibility coefficient; is the prior storage coefficient; is the observation time at i moment; is the regularization term, wherein is the regularization parameter.

3. The coal mine water inrush body deep part allochthonous dredging and storage method according to claim 2, characterized in that, The parameter inversion model performs a minimization search on the objective function by a particle swarm optimization algorithm (PSO) with the following specific operation steps: The particle swarm size NP is determined, and the value range of NP is [20, 100]; The search range of the water conductivity T and the water storage coefficient S is set according to the hydrogeological prior knowledge obtained by the mine exploration; Adopting linearly decreasing strategy to set inertia weight , the initial value range is [0.9, 1.2], the final value range is [0.4, 0.6], the learning factor , the learning factor The value range is [1.5, 2.0]. The initial position of each particle is taken as its individual historical optimal position P, and the position that makes the minimum is selected from all P as the group historical optimal position G; The particle velocity and position are updated, and the individual optimal is selected; Update group optimum: select the optimum position G with the best fitness from all updated individual optimum positions P, and update the position of each particle j Update according to the following formula: ， ， where, is the velocity of particle j; is the position of particle j; is the inertia weight; is the learning factor; is a random number between [0, 1]; k is the iteration number; is the individual historical best position of particle j; is the global historical best position.

4. The coal mine water inrush body deep part allochthonous dredging and storage method according to claim 1, characterized in that, The water level drawdown of the observation point in step S2 is calculated by using the optimal transmissibility T and storage coefficient S calculated by the parameter inversion model according to claims 2 and 3: ， In the formula, s is the water level drawdown of the observation point; Q is the flow of the water outlet; T is the transmissibility; t is the time from the start of water discharge to the calculation time; r is the distance from the calculation point to the water outlet; and S is the storage coefficient of the aquifer.

5. The coal mine water inrush body deep part allochthonous dredging and storage method according to claim 1, characterized in that, The closed collection pipeline in step S3 has the properties of being closed and pressure-resistant, and the closed collection pipeline is arranged by considering the structure of the underground aquifer and the position of the pre-drainage device to ensure that the pipeline is reasonably arranged and the path is unobstructed.

6. The coal mine water inrush body deep part allochthonous dredging and storage method according to claims 1-3, characterized in that, The optimal transmissibility T and storage coefficient S calculated by the parameter inversion model are used to predict the mine water inflow under the drainage time t and water level drawdown s: ， where: , where Q is the predicted inflow; T is the transmissibility; s is the water level drawdown at the observation point; is the Theis well function; u is the parameter of the Theis well function; r is the distance from the calculation point to the discharge well; S is the storage coefficient of the aquifer; and t is the time from the beginning of discharge to the calculation time.

7. The coal mine water inrush body deep part allochthonous dredging and storage method according to claim 1, characterized in that, In step S5, a dynamic evaluation system of reservoir capacity is established in the high-pressure back storage and heterotopic drainage system, and three reservoir capacity evaluation indexes are determined for grade evaluation, including theoretical reservoir capacity, effective reservoir capacity and actual water storage capacity; and the reservoir capacity evaluation index calculation method is as follows: Theoretical reservoir capacity calculation formula: ， In the formula, is the theoretical reservoir capacity; A is the water storage layer area; H is the water storage layer thickness; is the effective porosity; is the fracture development coefficient; Effective reservoir capacity calculation formula: ， In the formula, is the effective reservoir capacity; is the theoretical reservoir capacity; T is the optimal hydraulic conductivity calculated by parameter inversion; is the maximum hydraulic conductivity of the region; is the actual injection pressure; is the formation fracture pressure; is the hydraulic connection coefficient; Actual water storage capacity calculation formula: ， wherein is the actual water storage; is the injection rate; is the vertical leakage; is the lateral loss; and t is the injection time.

8. The coal mine water inrush body deep part allochthonous dredging and storage method according to claim 7, characterized in that, The reservoir capacity grade determination standard is as follows: Grade 1 reservoir capacity, set as high-quality water storage layer: meet the following conditions at the same time: , , , microseismic event frequency times / day; Level 2 reservoir capacity, set to medium water storage layer: meet any of the following conditions: , , , microseismic event frequency 5-15 times / day; Grade 3 reservoir capacity, set as limited water storage layer: meet any of the following conditions: , , , Microseismic event frequency > 15 times / day, formation pressure stability coefficient <0.

7.

9. The coal mine water inrush body deep part allochthonous dredging and storage method according to claim 1, characterized in that, In step S6, the early warning model is a single-factor early warning model or a multi-factor early warning model, and the early warning model provides early warning information for the coal mine user.

10. A coal mine water inrush body deep part heterotopic dredging and storage system for performing the coal mine water inrush body deep part heterotopic dredging and storage method of any one of claims 1-9, characterized in that, It includes: A water inrush body identification module is used to finely evaluate the hydrogeological conditions of the mine area according to the caving zone and water-conducting fractured zone after coal seam mining, to find out the spatial distribution and water abundance of the main water-filled aquifer of the coal mine, to determine the source of the water inrush body, to calculate the mine water inflow, and to construct a parameter inversion model and calculate the optimal transmissibility T and storage coefficient S by using a particle swarm optimization algorithm; A water drainage and pressure reduction system is used to drain and depressurize the water inrush body, including drill fields and water drainage boreholes arranged along the two roadways of the working face, and flowmeters and water pressure gauges installed on the water drainage boreholes, and the T and S coefficients calculated by using the inversion model are used to predict the mine water inflow and calculate the water level drawdown of the observation point; A drainage closed pipeline collection system is used to collect the underground water produced by the water drainage and pressure reduction and to transport the underground water to the high-pressure back storage equipment, including a closed collection pipeline connected to the water drainage borehole, and valves, flowmeters and water quality monitoring sensors arranged on the closed collection pipeline; A back storage stratum screening and well setting module is used to screen the back storage stratum and set back storage wells, and the back storage wells are vertical channels or directional channels; A high-pressure back storage and heterotopic drainage system is used to inject mine water into deep strata, including a storage pool, online water quality sensors, temperature sensors, a water inlet pump, a water injection pump, online flow sensors and water pressure sensors, the water injection pump is connected to the back storage well, and a dynamic evaluation system of reservoir capacity is established; A safety monitoring and early warning system is used to monitor the safety of the back storage process, including microseismic sensors and electrical sensors arranged on the ground and underground roadways of the coal mine, and armored optical fiber sensors laid in the back storage well and the monitoring well, and a single-factor or multi-factor early warning model is constructed.

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