High-geothermal-temperature mine retreat type mine-heat collaborative mining method

Abstract

The present application relates to the technical field of geothermal exploitation, and particularly relates to a high-geothermal-mine retreat type mine-geothermal collaborative exploitation method, comprising the following steps: step S1, drilling a hole downward along a coal seam floor from a hill; step S2, lowering a casing into the hole between the hill floor and a lower confined water and geothermal reservoir, and connecting a screen pipe at the bottom of the casing; step S3, passing a water delivery pipe into the hole from the hill, and extending the water delivery pipe along the casing and the screen pipe to a boundary of a mining stage; step S4, during the advancing of a working face, pulling the water delivery pipe at the hill, and locating the end of the water delivery pipe below the mining working face, and realizing self-flow or induced flow mining by using the geothermal reservoir pressure, and conveying the geothermal water along the water delivery pipe to the outside of the mine. The water delivery pipe is pulled synchronously with the advancing of the working face, and the "mining to where and water extraction to where" is realized, and the collaboration and efficiency of mining and water extraction are improved, and the problem of mutual interference between coal mining and geothermal water extraction is solved.

Description

Technical Field

[0001] This invention belongs to the technical field of geothermal extraction, specifically relating to a retreating mineral-thermal co-mining method for high-temperature mines. Background Technology

[0002] In high-temperature coal mining, the pressure and heat content of the confined aquifer in the lower part of the coal seam are higher than those in the shallow part. This leads to the waste of geothermal resources in deep coal seam mining, as well as problems such as heat hazards in high-temperature mines and water inrush from the confined aquifer in the floor. These issues have an increasingly serious impact on the safety of coal mining and the improvement of production efficiency. At present, deep coal seam mining and geothermal mining interfere with each other. The two are mostly operated independently and have not yet achieved coordinated development of multi-level resources. The coordination between mine heat hazard prevention and geothermal water development and utilization is poor, and the utilization efficiency of geothermal resources is low.

[0003] Therefore, there is a need to provide an improved technical solution that addresses the shortcomings of the existing technology. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art. This invention provides a retreat-type ore-thermal co-mining method for high-temperature mines.

[0005] To achieve the above objectives, the present invention provides the following technical solution: A retreat-type ore-thermal co-mining method for high-temperature mines includes the following steps: Step S1: Starting from the upper hill, drill holes downward along the bottom of the coal seam to form a drainage pipeline. After passing through the lower water-resistant layer, the drainage pipeline extends into the confined hydrothermal reservoir. Adjust the direction of the drainage pipeline in the confined hydrothermal reservoir so that the drainage pipeline extends to the boundary of the mining stage in a horizontal or near-horizontal direction. Step S2: A casing is installed in the extraction pipeline between the upper bottom plate and the lower confined hydrothermal reservoir. A screen pipe is connected to the bottom of the casing. The screen pipe extends along the extraction pipeline to the boundary of the mining stage within the confined hydrothermal reservoir. Step S3: Insert the water delivery pipe into the extraction pipeline from the uphill section, so that the water delivery pipe extends along the casing and screen pipe to the boundary of the mining stage; set up an extraction pump at the uphill section, and conduct trial extraction by connecting the extraction pump to the water delivery pipe. Step S4: During the advance of the working face, the water supply pipe is pulled uphill so that the end of the water supply pipe is located below the mining working face. The geothermal water is transported to the outside of the mine by gravity flow or diversion mining using the pressure of the thermal storage.

[0006] Preferably, in step S4, during the geothermal water extraction process, the advancing speed of the working face, the forward distance of the water pipe, and the geothermal water extraction flow rate, pressure, and temperature parameters are monitored in real time, and the traction rate of the water pipe is adjusted in real time to keep the water pipe and the advancing position of the working face synchronously corresponding, so that the retreating mining progress of the working face is dynamically adapted to the geothermal water extraction.

[0007] Preferably, in step S1, core samples are obtained by drilling into the coal seam and confined hydrothermal reservoir of the mine, and physical and mechanical parameters of the rock mass at each layer are obtained through indoor rock mechanics test and thermophysical property test. Geological exploration is used to obtain the burial depth, thickness, and occurrence state of coal seams and confined hydrothermal reservoirs, identify the lithology and thickness of the aquitard beneath the coal seam, determine the temperature, pressure, permeability, and hydrochemical characteristics of the confined hydrothermal reservoir beneath the coal seam, and determine the geothermal water extraction pipeline.

[0008] Preferably, sealing material is injected between the casing and the extraction pipeline to seal the outer side of the casing and the wall of the extraction pipeline. A connecting pipe is provided at one end of the screen pipe corresponding to the sleeve, and a sliding sealing mechanism is installed inside the connecting pipe to provide a sliding seal for the water supply pipe.

[0009] Preferably, a winch is installed on the uphill side, and the winch is connected to the upper end of the water supply pipe to pull the water supply pipe to move as the mining face advances.

[0010] Preferably, the screen tube has water-permeable holes evenly distributed on its sidewall, and the inner diameter of the screen tube is larger than the outer diameter of the water supply pipe.

[0011] Preferably, in step S4, after coal mining is completed, the water supply pipe is recovered and the extraction pipeline is sealed.

[0012] Preferably, the water supply pipe adopts a concentric double-layer pipe. The inner pipe is used to reinject the cooling water after the heat pump extracts heat energy, and the gap between the outer pipe and the inner pipe is used to extract hot water. A bottom packer is provided at the end of the water supply pipe to isolate the extraction area and the reinjection area.

[0013] Preferably, multiple extraction pipelines are distributed below the coal seam.

[0014] Preferably, multiple extraction pipelines converge at the uphill point and extend out of the coal seam floor through the same casing, and the water supply pipes corresponding to the multiple extraction pipelines are simultaneously pulled out as the mining face advances.

[0015] Beneficial effects: The traction water pipeline moves forward synchronously with the working face, realizing "wherever coal is mined, water is extracted", improving the coordination and efficiency of mining and extraction, solving the problem of mutual interference between coal mining and geothermal water extraction, and realizing the drainage and pressure reduction of the pressurized hydrothermal reservoir, effectively alleviating coal seam heat hazards, preventing water inrush risks, and ensuring the safety of coal mining.

[0016] Unlike the "indirect heat extraction" through buried pipes in the filling scheme, the extraction pipeline is buried in the pressurized hydrothermal reservoir, eliminating the thermal resistance effect caused by the filling medium and the pipe wall. This completely changes the situation in the traditional scheme where heat exchange pipelines occupy a large area of ​​the roadway bottom and side space, ensuring that the obtained heat source has a higher temperature and stable flow, significantly improving the energy recovery grade, and avoiding cross-interference between the heat extraction system and core production processes such as mine transportation, ventilation, and tunneling. Attached Figure Description

[0017] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. Wherein: Figure 1 This is a cross-sectional plan view of the retreating mineral-thermal co-mining method provided by the present invention; Figure 2 This is a schematic diagram of the retreating ore-thermal co-mining method provided by the present invention; Figure 3 This is a top view of the retreating ore-thermal co-mining method provided by the present invention; Figure 4 This is a schematic diagram of the arrangement of the sieve tubes provided by the present invention; Figure 5 This is a schematic diagram of the structure of the screen tube and water conveying pipe provided by the present invention.

[0018] In the diagram: 1. Uphill; 2. Transport roadway; 3. Extraction pipeline; 4. Coal mining roadway; 5. Mining face; 6. Screen pipe; 7. Return air roadway; 8. Winch; 9. Heat pump; 10. Water supply pipe; 11. Aquitard; 12. Confined hydrothermal reservoir; 13. Casing. Detailed Implementation

[0019] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention are within the scope of protection of the present invention.

[0020] In the description of this invention, the terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," and "bottom," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and do not require the invention to be constructed and operated in a specific orientation; therefore, they should not be construed as limitations on the invention. The terms "connected" and "linked" used in this invention should be interpreted broadly. For example, they can refer to a fixed connection or a detachable connection; they can refer to a direct connection or an indirect connection through intermediate components. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances.

[0021] The present invention will now be described in detail with reference to the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described herein can be combined with each other.

[0022] like Figures 1 to 5 As shown, a retreat-type ore-thermal co-mining method for high-geothermal mines achieves multi-objective synergy in the coordinated recovery of ore and thermal resources, prevention of water inrush, reduction of thermal hazards, and stability of the mining system structure. Specifically, it includes the following steps: Step S1: Starting from the upper slope 1, drill downwards along the coal seam floor to form the extraction pipeline 3. It should be noted that the upper slope 1 is a mining term referring to an inclined roadway serving a mining area or panel. Its main transport roadway is located in the lower part of the mining area and is used to transport coal seams above the mining level downwards. The extraction pipeline 3 passes downwards through the lower water-resistant layer 11 and extends into the confined hydrothermal reservoir 12. In the confined hydrothermal reservoir 12, adjust the direction of the extraction pipeline 3 so that the extraction pipeline 3 extends horizontally or nearly horizontally to the boundary of the mining stage. The diameter of the extraction pipeline 3 is designed according to the specifications of the subsequent casing 13, screen pipe 6, and water conveyance pipe 10. When adjusting the direction of the extraction pipeline 3 in the confined hydrothermal reservoir 12, a smooth transition is used to transition with the vertical end of the extraction pipeline 3. Directional drilling technology is used to ensure that the extraction pipeline 3 is excavated according to the preset direction.

[0023] Step S2: After the extraction pipeline 3 is completed, a hole cleaning operation is performed. After the hole cleaning is completed, a casing 13 is installed in the extraction pipeline 3 between the bottom plate of the upper slope 1 and the lower pressurized hydrothermal reservoir 12. A screen pipe 6 is connected to the bottom of the casing 13. The screen pipe 6 extends along the extraction pipeline 3 to the boundary of the mining stage within the pressurized hydrothermal reservoir 12. The casing 13 and the screen pipe 6 are made of high-strength and corrosion-resistant materials, such as stainless steel, to isolate the borehole wall of the extraction pipeline 3 from the geothermal water and prevent the borehole wall from collapsing and impurities from entering the pipeline.

[0024] Step S3: Insert the water supply pipe 10 from the uphill section 1 into the extraction pipeline 3, so that the water supply pipe 10 extends along the casing 13 and screen pipe 6 to the boundary of the mining stage. The water supply pipe 10 is a flexible pipe with high temperature resistance, high pressure resistance, and corrosion resistance, such as PPR pipe, which is convenient for subsequent extraction and movement as the working face advances. An extraction pump is set up at the uphill section 1, and the water supply pipe 10 is connected to the extraction pump for trial extraction. The trial extraction is used to test the sealing of the water supply pipe 10, the operating status of the extraction pump, and the flow rate, pressure, temperature and other parameters of the geothermal water, and to check for pipeline leaks, blockages and other problems. After ensuring that the extraction system is operating stably, the formal mining stage can begin.

[0025] Step S4: The working face adopts a retreating mining and advancement method. During the advancement of the working face, the water supply pipe 10 is pulled out at the uphill 1. The pulling speed of the water supply pipe 10 is synchronized with the advancement speed of the working face, so that the end of the water supply pipe 10 is located below the mining working face 5. This ensures that the geothermal water extraction always covers the current mining area, making full use of geothermal energy resources while reducing the risk of heat hazards and water inrush around the working face and improving the working environment. The geothermal water is transported to the outside of the mine along the water supply pipe 10 using gravity flow or diversion mining based on the pressure of the thermal reservoir. Specifically, when the local thermal reservoir pressure meets the gravity flow conditions, the extraction pump can be stopped and the geothermal water can be extracted by gravity flow to reduce energy consumption. When the local thermal reservoir pressure is insufficient, the extraction pump is started for diversion mining to ensure the continuity and stability of geothermal water extraction.

[0026] Once coal mining in a certain stage is completed, geothermal water extraction is stopped. The water supply pipe 10 is completely extracted from the extraction pipeline 3 using the winch 8. After the water supply pipe 10 is retrieved, the extraction pipeline 3 is sealed. The sealing is done in sections, with sealing materials (such as cement mortar, sealant, etc.) injected sequentially from the bottom to the top of the extraction pipeline 3 to ensure a tight seal and prevent groundwater or geothermal water from crossing layers through the extraction pipeline 3, thus avoiding geological environmental problems. After sealing, the opening of the extraction pipeline 3 is reinforced and marked to facilitate subsequent geological exploration and mine maintenance.

[0027] In an optional embodiment, in step S4, during the geothermal water extraction process, the advancing speed of the working face, the forward distance of the water pipe 10, and the geothermal water extraction flow rate, pressure, and temperature parameters are monitored in real time. The traction rate of the water pipe 10 is adjusted in real time to keep the water pipe 10 synchronized with the advancing position of the working face, so that the retreating mining progress of the working face is dynamically adapted to the geothermal water extraction.

[0028] Specifically, the advancing speed of the working face is recorded; a displacement sensor is installed on the water supply pipe 10 to monitor the forward distance of the water supply pipe 10 in real time; flow, pressure, and temperature sensors are installed at the outlet of the water supply pipe 10 and in the extraction pipeline 3 to collect geothermal water extraction parameters in real time; all monitoring data are transmitted to the ground control center, where the control center analyzes and processes the data, and automatically or manually adjusts the traction rate of the water supply pipe 10 according to the advancing speed of the working face to ensure that the end of the water supply pipe 10 is always below the working face 5, so that geothermal water extraction can keep up with the advancement of the working face in a timely manner, avoiding problems such as excessively high ground temperature in the mining area or insufficient geothermal water extraction; at the same time, the operating parameters of the extraction pump or the position of the water supply pipe 10 are adjusted in a timely manner according to changes in the geothermal water extraction flow, pressure, and temperature to ensure the dynamic balance of mineral-thermal co-mining.

[0029] Furthermore, prior to mining, core samples are obtained from various strata, including the coal seam, aquitard 11, and confined hydrothermal reservoir 12, through drilling. These core samples are then sent to a laboratory for indoor rock mechanics testing to determine the compressive strength, tensile strength, elastic modulus, and other physical and mechanical parameters of the rock mass. This provides parameter support for drilling operations, casing 13 installation, and water pipe 10 traction. Simultaneously, thermal property tests are conducted to obtain thermal properties such as thermal conductivity and specific heat capacity of the rock mass at each stratum, providing a basis for geothermal temperature control and geothermal energy utilization.

[0030] Geological exploration methods such as ground-penetrating radar and seismic exploration are used to obtain the burial depth, thickness, and occurrence state of the coal seam, identify the lithology and thickness of the aquitard 11 under the coal seam, and determine the temperature, pressure, permeability, and hydrochemical characteristics of the confined hydrothermal reservoir 12 under the coal seam. This clarifies the mining scope, accurately identifies the lithology (such as mudstone, shale, etc.), thickness, and distribution continuity of the aquitard 11 under the coal seam, and judges the water-blocking performance of the aquitard 11 to avoid damage to the aquitard 11 during drilling construction, which could lead to geothermal water cross-contamination. Pumping tests and water sample analysis are used to determine the temperature, pressure, and permeability of the geothermal water in the confined hydrothermal reservoir 12, analyze the hydrochemical characteristics of the geothermal water (such as ionic composition, pH, etc.), and confirm the geothermal water recharge channel, flow direction, and discharge path. This provides a scientific basis for the layout of the extraction pipeline 3 and the design of geothermal water extraction parameters, thereby determining the extraction pipeline 3.

[0031] In another embodiment, after the casing 13 is lowered into the extraction pipeline 3, sealing material is injected between the casing 13 and the borehole wall. The sealing material is a high-strength, corrosion-resistant, water-swellable sealant or cement mortar to seal the outer side of the casing 13 and the wall of the extraction pipeline 3, preventing geothermal water from leaking into the coal seam or roadway and avoiding geothermal hazards and groundwater pollution. A connecting pipe is installed at the connection between the screen pipe 6 and the casing 13. The connecting pipe uses the same material and diameter as the casing 13 and the screen pipe 6. One end of the connecting pipe is fixedly connected to the bottom of the casing 13, and the other end is seamlessly connected to the screen pipe 6. A sliding sealing mechanism is installed inside the connecting pipe to provide a sliding seal for the water delivery pipe 10. The sliding sealing mechanism uses a high-temperature resistant and wear-resistant sealing ring, which can maintain the sealing performance between the water delivery pipe 10 and the connecting pipe during the pulling and moving of the water delivery pipe 10, preventing geothermal water from leaking from the gap between the water delivery pipe 10 and the connecting pipe, and ensuring that all geothermal water can be transported to the outside of the mine along the water delivery pipe 10.

[0032] A winch 8 is installed at the designated location on the uphill section 1. The traction rope of the winch 8 is fixedly connected to the connection device at the upper end of the water supply pipe 10 through a guide pulley. During the advancement of the working face, the water supply pipe 10 is pulled to move along with the advancement of the mining working face 5. During the extraction, by controlling the start, stop and speed of the winch 8, the water supply pipe 10 is pulled forward synchronously, so that the end of the water supply pipe 10 always corresponds to the advancement position of the working face.

[0033] Preferably, the screen pipe 6 has evenly distributed permeable holes on its sidewalls. These permeable holes are either round or strip-shaped. The inner diameter of the screen pipe 6 is larger than the outer diameter of the water delivery pipe 10, ensuring that geothermal water can smoothly enter the screen pipe 6 through the permeable holes while effectively preventing rock debris and impurities from entering the pressurized hydrothermal reservoir 12. The total area of ​​the permeable holes is designed according to the expected geothermal water extraction flow rate to ensure that the water delivery demand is met and to avoid a decrease in geothermal water extraction efficiency due to insufficient permeable hole area. The inner diameter of the screen pipe 6 is 2-3 times the outer diameter of the water delivery pipe 10. This facilitates the free movement of the water delivery pipe 10 inside the screen pipe 6, reducing friction and wear between the water delivery pipe 10 and the screen pipe 6, and extending the service life of the pipeline. On the other hand, it provides sufficient flow space for the geothermal water, ensuring that the geothermal water can quickly enter the water delivery pipe 10 and improve extraction efficiency.

[0034] In this embodiment, to improve the utilization efficiency of geothermal energy resources, the water transmission pipe 10 adopts a concentric double-layer pipe structure, with an annular gap between the outer and inner pipes. The inner pipe is used to reinject the cooling water extracted by the heat pump 9 into the pressurized hydrothermal reservoir 12. The gap between the outer and inner pipes is used to extract hot water, realizing the recycling of geothermal water, reducing water waste, and maintaining the pressure balance of the pressurized hydrothermal reservoir 12 to avoid a drop in the water level of the pressurized hydrothermal reservoir 12 due to excessive extraction. A bottom packer is installed at the end of the water transmission pipe 10. The bottom packer can effectively seal the inner and outer pipes between the end of the water transmission pipe 10 and the inner wall of the screen pipe 6, separating the extraction area from the reinjection area, preventing the extracted geothermal water from mixing with the reinjected cooling water, and ensuring the quality of geothermal water extraction and the reinjection effect. The bottom packer moves synchronously with the water transmission pipe 10, always maintaining effective isolation between the extraction area and the reinjection area.

[0035] In another embodiment, to achieve uniform extraction of geothermal water throughout the entire mining area, multiple extraction pipelines 3 are evenly distributed between the transport roadway and the return air roadway 7. These pipelines are arranged at specific intervals between the transport roadway and the return air roadway 7. The spacing of the extraction pipelines 3 is designed based on the coal seam thickness, the permeability of the confined hydrothermal reservoir 12, and the distribution of geothermal water, generally ranging from 50 to 100 meters, ensuring that the extraction ranges of each extraction pipeline 3 are interconnected and there are no blind spots. Each extraction pipeline 3 is constructed and fitted with a casing 13, a screen pipe 6, and a water delivery pipe 10 according to steps S1-S4, forming multiple independent geothermal water extraction units. These units collectively achieve geothermal water extraction and geothermal temperature control throughout the entire mining face 5, further improving the efficiency and effectiveness of the ore-thermal co-mining process.

[0036] Multiple extraction pipelines 3 converge at the uphill position 1, and then extend out of the coal seam floor through the same main casing 13. The diameter of the casing 13 is larger than the diameter of the screen pipes 6 of each branch extraction pipeline 3, ensuring that all branch water conveyance pipes 10 can pass through smoothly. The casings 13 of each branch extraction pipeline 3 are sealed to the main casing 13 to prevent geothermal water leakage. The water conveyance pipe 10 corresponding to each extraction pipeline 3 is connected to the winch 8 at the uphill position 1. The operation of all winches 8 is controlled by a unified control system, so that multiple water conveyance pipes 10 are synchronously pulled out as the mining face 5 advances. This ensures that the end of each water conveyance pipe 10 always corresponds synchronously with the advancing position of the working face, achieving uniform and synchronous extraction of geothermal water throughout the mining area. This avoids problems such as excessively high local ground temperature or insufficient geothermal water extraction, further improving the coordination and efficiency of the mine-thermal co-mining.

[0037] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention shall be within the scope of protection of the pending claims of the present invention.

Claims

1. A method for retreating ore-thermal co-mining in high-temperature mines, characterized in that, Includes the following steps: Step S1: Starting from the upper hill, drill holes downward along the bottom of the coal seam to form a drainage pipeline. After passing through the lower water-resistant layer, the drainage pipeline extends into the confined hydrothermal reservoir. Adjust the direction of the drainage pipeline in the confined hydrothermal reservoir so that the drainage pipeline extends to the boundary of the mining stage in a horizontal or near-horizontal direction. Step S2: A casing is installed in the extraction pipeline between the upper bottom plate and the lower confined hydrothermal reservoir. A screen pipe is connected to the bottom of the casing. The screen pipe extends along the extraction pipeline to the boundary of the mining stage within the confined hydrothermal reservoir. Step S3: Insert the water delivery pipe into the extraction pipeline from the uphill section, so that the water delivery pipe extends along the casing and screen pipe to the boundary of the mining stage; set up an extraction pump at the uphill section, and conduct trial extraction by connecting the extraction pump to the water delivery pipe. Step S4: During the advance of the working face, the water supply pipe is pulled uphill so that the end of the water supply pipe is located below the mining working face. The geothermal water is transported to the outside of the mine by gravity flow or diversion mining using the pressure of the thermal storage.

2. The method for retreating mineral-thermal co-mining in high-temperature mines according to claim 1, characterized in that, In step S4, during the geothermal water extraction process, the advancing speed of the working face, the forward distance of the water delivery pipe, and the geothermal water extraction flow rate, pressure, and temperature parameters are monitored in real time. The traction rate of the water delivery pipe is adjusted in real time to keep the water delivery pipe synchronized with the advancing position of the working face, so that the retreating mining progress of the working face is dynamically adapted to the geothermal water extraction.

3. The method for retreating mineral-thermal co-mining in high-temperature mines according to claim 1, characterized in that, In step S1, core samples are obtained by drilling into the coal seam and confined hydrothermal reservoir in the mine, and physical and mechanical parameters of the rock mass at each layer are obtained through indoor rock mechanics tests and thermophysical property tests. Geological exploration is used to obtain the burial depth, thickness, and occurrence state of coal seams and confined hydrothermal reservoirs, identify the lithology and thickness of the aquitard beneath the coal seam, determine the temperature, pressure, permeability, and hydrochemical characteristics of the confined hydrothermal reservoir beneath the coal seam, and determine the geothermal water extraction pipeline.

4. The method for retreating mineral-thermal co-mining in high-temperature mines according to claim 1, characterized in that, Inject sealing material between the casing and the extraction pipeline to seal the outer side of the casing and the wall of the extraction pipeline. A connecting pipe is provided at one end of the screen pipe corresponding to the sleeve, and a sliding sealing mechanism is installed inside the connecting pipe to provide a sliding seal for the water supply pipe.

5. The method for retreating mineral-thermal co-mining in high-temperature mines according to claim 1, characterized in that, A winch is installed on the mountainside and connected to the upper end of the water supply pipe to pull the water supply pipe as the mining face advances.

6. The method for retreating mineral-thermal co-mining in high-temperature mines according to claim 1, characterized in that, The screen tube has water-permeable holes evenly distributed on its sidewall, and the inner diameter of the screen tube is larger than the outer diameter of the water supply pipe.

7. The method for retreating mineral-thermal co-mining in high-temperature mines according to claim 1, characterized in that, In step S4, after the coal mining is completed, the water supply pipe is recovered and the extraction pipeline is sealed.

8. The method for retreating mineral-thermal co-mining in high-temperature mines according to claim 1, characterized in that, The water supply pipe adopts a concentric double-layer pipe. The inner pipe is used to reinject the cooling water after the heat pump extracts heat energy. The gap between the outer and inner pipes is used to extract hot water. A bottom packer is installed at the end of the water supply pipe to isolate the extraction area and the reinjection area.

9. The method for retreating mineral-thermal co-mining in high-temperature mines according to claim 1, characterized in that, Multiple extraction pipelines are distributed beneath the coal seam.

10. The method for retreating mineral-thermal co-mining in high-temperature mines according to claim 9, characterized in that, Multiple extraction pipelines converge at the uphill point and extend out of the coal seam floor through the same casing. The water supply pipes corresponding to the multiple extraction pipelines are simultaneously pulled out as the mining face advances.

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