Method for co-mining coal and associated uranium deposits

Abstract

The application discloses a method for jointly mining coal and symbiotic uranium mine, and belongs to the technical field of mine exploitation. The method is specifically as follows: a coal mine field is divided into three zones, one wing of the field is a uranium mine preferential mining zone, the other wing is a coal mine mining zone, and the middle part is a protection zone; liquid pumping and injecting wells for in-situ leaching of the uranium mine are arranged in the coal mine underground; then, a coal seam in the coal mine mining zone of the coal mine field is mined, and meanwhile, the liquid pumping and injecting wells for the uranium mine are constructed downwardly by using a mining preparation roadway in the uranium mine preferential mining zone to perform in-situ leaching of the uranium mine; after the uranium mine is mined, the overlying coal seam of the uranium mine is mined, and the underlying coal seam of the uranium mine is mined by using a filling type or in-situ unmanned mining. The method for jointly mining the coal mine and the uranium mine can avoid the influence of uranium mine mining on subsequent coal mine mining, saves engineering quantity, and improves the confidentiality of uranium mine mining.

Description

Technical Field

[0001] This invention relates to the field of mineral mining technology, specifically to a method for co-mining coal and associated uranium deposits. Background Technology

[0002] Coal and uranium are typical strategic metallic minerals associated with coal in my country, and uranium deposits are of great strategic significance to national defense and energy security. However, the occurrence and mining methods of uranium and coal differ greatly. Traditional underground coal mining and in-situ leaching of uranium both present challenges in mining this associated mineral. Rock activity and fluid migration caused by mining activities affect the normal operation of both, leading to conflicts between coal and uranium mining.

[0003] Coal-uranium mining involves two scenarios: "uranium above coal" and "coal above uranium." Under traditional mining conditions considering only a single mineral, the problems encountered in coal-uranium mining differ. The main problems with "coal above uranium" mining are: ① The impact of coal mining on uranium mining mainly includes: the dewatering and depressurization of the aquifer at the bottom of the coal mine causes a drop in the water level of the uranium-bearing aquifer, making normal uranium mining impossible; and the construction of uranium injection wells traversing the coal mine's goaf, leading to drilling difficulties. ② The main impacts of uranium mining on coal mining include: the dense injection wells (20-25m spacing between wells) in uranium leaching mining can disrupt the continuity of the coal seam; when the coal mining face encounters uranium injection wells, the cutting of the well shaft by the coal mining machine may generate sparks, affecting the safe production of the coal mine, etc.; while the main problems of "uranium above coal" mining are: ① The main impacts of coal mining on uranium mining include: the rock activity caused by coal mining leads to the rupture of the uranium aquitard, and the drainage and depressurization of the coal mine causes the water level of the uranium-bearing aquifer to drop, making it impossible to mine uranium normally, etc.; ② The main impacts of uranium mining on coal mining include: pollutants and radionuclides from uranium leaching mining migrate to the coal mine with the groundwater, affecting the safe production of the coal mine, etc.

[0004] In view of the drawbacks of traditional mining methods in coal-uranium coexisting areas, there is an urgent need to propose new methods that can effectively resolve the contradiction between coal and associated uranium mining, thereby reducing the waste of strategic resources and providing scientific and technological support for ensuring the secure supply of my country's strategic mineral resources. Summary of the Invention

[0005] The technical problem this invention aims to solve is: how to conduct coordinated mining of coal-uranium symbiotic minerals to achieve orderly and safe mining and improve the mining rate.

[0006] The inventive concept of this invention is based on the principle of "spatial separation and temporal staggering" in coal-uranium co-mining. The coal mine field is divided into three zones: one wing is the priority mining zone for uranium ore, the other wing is the coal mining zone, and the middle is the protection zone. The uranium leaching extraction and injection wells are arranged underground in the coal mine. Coal seams are mined in one wing of the coal mine field, while the coal mine preparation roadway is constructed in the other wing. Uranium ore extraction and injection wells are then constructed downwards through the coal mine preparation roadway for uranium leaching mining. Afterward, the overlying and overburdening coal seams are mined.

[0007] The technical solution of the present invention: a method for co-mining coal and associated uranium ore, characterized by comprising the following steps:

[0008] S1. Conduct geological exploration and collect geological and hydrological information of the mining area through exploration drilling in the coal-uranium co-mining area;

[0009] S2. Divide the mining area into three areas according to whether the coal mine field is superimposed with uranium mines. One wing of the mine field is the coal-uranium superposition area, which is the priority mining area for uranium mines. The other wing is the coal mining area where the coal seams are not superimposed with uranium mines. The middle of the two wings is the protection area.

[0010] S3. Establish coal mine production system and uranium mine production system, construct vertical shafts to the coal seam, and excavate preparatory roadways in the coal mining area and the uranium priority mining area respectively; form a complete coal mining system in the coal mining area, and construct injection wells, pumping wells and monitoring wells into the uranium ore-bearing and water-bearing strata in the track roadway of the uranium priority mining area to form a uranium mining system.

[0011] S4. Mining coal and uranium mines, recovering coal from the coal mining area, and simultaneously leaching uranium in the priority mining area of ​​the uranium mine, using the coal mining roadway excavated in step S3 to transport the leaching solution.

[0012] S5. Mining coal in the priority mining area of ​​uranium ore, and permanently sealing the pumping, injection and monitoring wells after the uranium ore mining is completed; improving the coal mine production system in the area based on the mining preparation roadway in the priority mining area of ​​uranium ore, and mining the overlying coal seam of uranium ore; after the overlying coal seam is mined, mining the underlying coal seam of uranium ore.

[0013] S6. After the coal seam overlying the uranium mine is mined, tunnels are excavated in the coal seam of the protected area to mine the coal seam of the protected area.

[0014] As a further technical solution of the present invention, in step S1, the geological and hydrological information of the mining area specifically includes: the occurrence characteristics and distribution range of coal and associated uranium, the physical and mechanical properties of the coal seam and the top and bottom plates of the coal seam as well as the water level and head of the ore-bearing aquifer.

[0015] As a further technical solution of the present invention, in step S2, the method for establishing the protected area is as follows: using the rock physical and mechanical property parameters measured in step S1, through numerical simulation and physical similarity simulation methods, the evolution law of coal seam mining-induced fractures and the distribution characteristics of mining-induced rock mass stress field are obtained, and the range of disturbance of coal mining to the surrounding rock mass is determined, which is the range of the protected area.

[0016] As a preferred technical solution of the present invention, in step S3, a suitable drilling spacing is determined based on the hydrogeological conditions obtained from exploration; according to the layout of the coal mine preparation roadway, the uranium mine drilling is designed as inclined shafts at different angles, and the number of inclined shafts varies with the width of the working face; the inclined shafts are used to increase the coverage area of ​​the uranium reservoir by the drilling, reduce the spacing between the uranium reservoir injection points, and thereby improve the resource recovery rate.

[0017] As a preferred technical solution of the present invention, in step S3, according to the layout of the coal mine preparation roadway, the uranium mine drilling is designed as an "L-shaped" horizontal well. The middle horizontal well is used to inject leaching solution, and the horizontal wells on both sides are used to extract leaching solution. The leaching solution is extracted and injected using the holes in the horizontal well section. The horizontal well is used to increase the contact area between the leaching point of the leaching solution and the uranium reservoir, thereby improving the leaching extraction efficiency.

[0018] As a further technical solution of the present invention, in step S3, when constructing injection wells, pumping wells, and monitoring wells in the priority mining area of ​​uranium ore, the presence of the lower aquifer causes the drilling to be conducted under pressure. The method to prevent drilling water inrush is as follows:

[0019] (1) Use a pressure-bearing drilling rig and pre-install the pressure-bearing sleeve at the borehole opening;

[0020] (2) Use a high-pressure grouting pump to solidify the cement. After the borehole pipe is installed, attach a control gate valve and control the water volume after the water comes out of the borehole. (3) When the water pressure in the borehole is expected to be greater than 1.5 MPa, use the method of back pressure and blowout prevention device to drill.

[0021] As a further technical solution of the present invention, in step S4, the pumping route of the uranium ore leaching solution is: surface industrial square → auxiliary shaft → bottom shaft yard → main track roadway → track uphill → track level roadway → injection well. The extraction route of the leaching solution is opposite to the pumping route, and after being pumped to the surface, it is further filtered and purified.

[0022] As a further technical solution of the present invention, in step S5, during the mining of the coal seam overlying the uranium mine, the bottom plate is reinforced by grouting to seal any possible water-conducting cracks in the bottom plate and further prevent water inrush from the bottom plate.

[0023] As a preferred technical solution of the present invention, in step S5, the uranium ore overlying coal seam is mined by filling method. The specific method is: by filling the goaf with solid, paste or high water material, the movement of the overlying strata is controlled, and the formation of interlayer fissures is avoided so that pollutants in the groundwater of the uranium mine decommissioning area migrate to the coal mining face below.

[0024] As a preferred technical solution of the present invention, in step S5, the uranium ore-covered coal seam is mined in situ without human intervention, including underground coal gasification and in-situ microbial hydrogen production. This in-situ unmanned mining method fundamentally avoids safety issues. Underground coal gasification involves controlled combustion of coal in situ, producing combustible gases such as H2, CO, and CH4 through pyrolysis and a series of chemical reactions between the coal and oxygen and water vapor. Microbial hydrogen production utilizes the metabolism of specific microorganisms to generate hydrogen.

[0025] The beneficial effects of this invention are:

[0026] This invention overcomes the drawbacks of traditional mining methods, which involve severe mutual interference between uranium and coal mining, particularly in the "coal above, uranium below" occurrence pattern. By placing the uranium leaching injection wells underground in the coal mine, the impact of uranium mining on subsequent coal mining is avoided, saving on engineering work and improving the confidentiality of uranium mining. For "uranium above, coal below" overlying coal seams, this invention overcomes the limitations of traditional mining methods, which easily induce inter-layer fractures, causing pollutants from groundwater in decommissioned uranium mining areas to migrate to the coal face. It employs a backfilling method to mine the overlying coal seam, controlling the migration of overlying strata and preventing the formation of inter-layer fractures that could lead to the migration of pollutants from groundwater in decommissioned uranium mining areas to the underlying coal face. Alternatively, it utilizes disruptive mining technologies such as in-situ unmanned coal mining, including underground coal gasification and in-situ microbial hydrogen production, to fundamentally avoid safety issues through unmanned in-situ coal mining. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the on-site layout for the co-mining of coal and associated uranium ore according to the present invention;

[0028] Figure 2 This is a schematic diagram of the horizontal well mining method for co-mining coal and associated uranium ore according to the present invention;

[0029] Figure 3 This is a top view of the drilling layout for uranium mine inclined shaft mining, an embodiment of the present invention, where coal and associated uranium ore are co-mined.

[0030] Figure 4 This is a top view of the drilling layout for uranium mine inclined shaft mining, which is a co-mining method for coal and associated uranium ore, according to another embodiment of the present invention.

[0031] Figure 5 This is a schematic diagram of the backfilling mining method for uranium ore covering coal seams;

[0032] Figure 6 This is a schematic diagram of the microbial in-situ mining method for uranium ore overlying coal seams;

[0033] In the diagram, 1-coal seam; 2-uranium ore-bearing aquifer; 3-uranium orebody; 4-coal mining area; 5-protected area; 6-uranium priority mining area; 7-main shaft; 8-auxiliary shaft; 9-bottom yard; 10-main track roadway; 11-main transport roadway; 12-transport uphill roadway; 13-main track uphill roadway; 14-level track roadway; 15-level transport roadway; 16-return airway; 17-ventilation shaft; 18-coal mining face; 19-injection well; 20-extraction well. 21-Monitoring well; 22-Collection pool; 23-Hydrometallurgical plant; 24-Liquid preparation room; 25-Coal seam covered by uranium ore; 26-Backfill material; 27-Pollutants from uranium mining; 28-Bacterial solution injection well; 29-Microbial solution; 30-Coal seam fracture network; 31-Coal microbial mining area; 32-Gas extraction well; 33-Horizontal well; 34-Injection well in inclined shaft; 35-Liquid extraction well in inclined shaft; 36-Injection and extraction unit; 37-Width of coal mining face. Detailed Implementation

[0034] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0035] A large-scale coal-uranium coexistence exists on the southern edge of the Ili Basin in Xinjiang. This embodiment takes a sandstone-type uranium deposit in Xinjiang as an example to explain in detail the method of co-mining coal and co-existing uranium.

[0036] like Figure 1 As shown, coal seam 1 and uranium ore body 3 are spatially stacked, with one wing of the mining area overlying uranium ore and the other wing not. The conflict between mining the upper coal seam and mining the lower uranium ore is significant, and improper handling could lead to serious waste of strategic mineral resources and radioactive contamination. Therefore, it is necessary to implement "coal-uranium co-mining" for coal and associated sandstone-type uranium deposits. To address the above problems, the present invention provides a method for co-mining coal and associated uranium, the specific steps of which are as follows:

[0037] Step S1: Conduct geological exploration: In the coal-uranium co-mining area, drill holes from the surface down to the top and bottom strata of coal seam 1 and uranium-bearing aquifer 2 to obtain the occurrence characteristics, distribution range, and hydrogeological information of coal and associated uranium deposits. This information includes the physical and mechanical properties of the coal seam and its top and bottom strata, as well as the water level and head of uranium-bearing aquifer 2. Based on the core samples obtained from drilling, test the physical and mechanical properties of the rocks in each stratum, including: porosity, permeability, uniaxial compressive strength, tensile strength, cohesion, internal friction angle, elastic modulus, Poisson's ratio, and fracture toughness. Focus on detecting faults, collapse columns, and other easily water-conducting geological structures. All boreholes are fully grouted and sealed during the drilling process.

[0038] Step S2: Divide the mining area: Divide the coal mine field into three areas. One wing of the field is a coal-uranium superposition zone, designated as the uranium priority mining zone 6. The other wing contains coal seams not superimposed with uranium, designated as the coal mining zone 4. A protection zone 5 is reserved between the two winges, and will not be mined during uranium mining. The principle for determining the protection zone is as follows: using the rock physical and mechanical property parameters obtained from geological exploration, numerical simulation and physical similarity simulation methods are used to obtain the evolution law of coal seam mining-induced fractures and the stress field distribution characteristics of the mining-induced rock mass, thus clarifying the range of disturbance to the surrounding rock mass caused by coal mining, which is the range of protection zone 5. Protection zone 5 serves as an isolation buffer between coal mining zone 4 and uranium priority mining zone 6, reducing the mutual influence between coal and uranium mining.

[0039] Step S3: Establish the coal mine production system and the uranium mine production system: Construct the main shaft 7, auxiliary shaft 8, and ventilation shaft 17 to coal seam 1; construct the bottom shaft yard 9; and construct preparatory roadways from the bottom shaft yard 9 to both sides of the minefield, including: main track roadway 10, main haulage roadway 11, haulage uphill roadway 12, main track uphill roadway 13, track level roadway 14, haulage level roadway 15, and return air roadway 16, forming the coal mine production system of coal mining area 4 and the uranium mine production system of uranium priority mining area 6. No roadways will be excavated in the protected coal seams initially.

[0040] A leaching solution transport pipeline was laid in the preparation roadway of the uranium mining priority mining area 6. Based on the hydrogeological conditions obtained from the exploration, an appropriate drilling spacing was determined, and the uranium mining was divided into several extraction and injection units 36. Each extraction and injection unit 36 ​​included a pumping well 19 and an injection well 20, while the monitoring well 21 was used to observe the aquifer water level and monitor the migration of pollutants.

[0041] When establishing a uranium mining system, uranium drilling can be carried out in two ways. The first way is to design the uranium well as an L-shaped horizontal well, based on the layout of the coal mine preparation roadways. Figure 2 As shown, drilling horizontal wells utilizes the perforations in the horizontal section of the wellbore to inject and extract leaching fluid. The second method involves designing uranium mine wells as inclined wells at different angles, such as... Figure 3 and Figure 4 As shown, the inclined shaft layout can adopt a "four-injection, two-extraction" method. Figure 3 ) or "three bets and one draw" ( Figure 4 In the injection unit 36, inclined injection wells 34 and inclined extraction wells 35 are drilled from the track level tunnel 14 into the uranium-bearing aquifer 2. The wells located diagonally opposite the injection unit 36 ​​are vertical wells, while adjacent inclined wells penetrate the uranium ore layer at different angles. When drilling inclined wells, the number of inclined wells should vary with the working face width 37; as the working face width 37 increases, the number of inclined wells also increases accordingly to ensure appropriate spacing between injection and extraction points in the uranium reservoir. Figure 3 and Figure 4It can be seen that in a pumping unit 36, whether it is the inclined injection well 34 or the inclined pumping well 35, the inclination angles of two adjacent inclined wells are symmetrical. This layout is also the overall layout of a uranium mine. This layout is conducive to increasing the coverage area of ​​the uranium reservoir by drilling, reducing the spacing between the pumping points of the uranium reservoir, and thus improving the resource recovery rate.

[0042] Please refer to Figure 1 and Figure 3 or Figure 4 In this invention, the uranium leaching injection wells are located within the coal seam of the priority mining area 6 (i.e., the overlying coal seam of the uranium ore). The injection wells are established using the preparatory roadway of the overlying coal seam. This approach saves on drilling work and enhances the confidentiality of uranium mining operations. Furthermore, by designing the uranium drilling wells as inclined shafts at different angles within the coal mine preparatory roadway, the drilling coverage area of ​​the uranium reservoir is increased, the spacing between injection points in the uranium reservoir is reduced, and the uranium extraction efficiency is improved.

[0043] During drilling in the uranium priority mining area 6, measures were taken to prevent water inrush. A specialized pressure-bearing drilling rig was used, and a pressure-bearing casing was pre-installed at the borehole opening. High-pressure grouting pumps were used for cement consolidation. After the casing was installed, a control gate valve was installed to control the water flow after water was encountered in the borehole. When the expected water pressure inside the borehole exceeded 1.5 MPa, drilling was carried out using a back pressure method with a blowout preventer. Simultaneously, grouting was used to reinforce the bottom plate to further prevent water inrush disasters during drilling in the uranium priority mining area 6.

[0044] Step S4: Mining Coal and Uranium: Coal is mined from mining area 4 of the coal mine to form a coal mining face 18. Simultaneously, uranium is leached in the priority mining area 6 of the uranium mine, with the extraction volume slightly exceeding the injection volume, creating negative pressure mining in the uranium mining area. This invention employs in-situ leaching uranium mining technology, a highly advanced mining technology worldwide. Its basic principle involves drilling holes in a specific grid pattern in leached sandstone-type uranium deposits, injecting leaching solution through injection holes to allow the leaching solution to fully react with the uranium, and then extracting the uranium through extraction holes to the surface in a surface plant. The pumping route for the uranium ore leaching solution is: Solution preparation room 24 → Auxiliary shaft 8 → Bottom shaft yard 9 → Main track roadway 10 → Track incline 13 → Track horizontal roadway 14 → Injection well 19. The extraction route for the leaching solution is: Extraction well 20 → Track horizontal roadway 14 → Track incline 13 → Main track roadway 10 → Bottom shaft yard 9 → Auxiliary shaft 8 → Collection pool 22 → Hydrometallurgical plant 23 → Solution preparation room 24. The extraction route is the opposite of the pumping route; after being pumped to the surface, the leaching solution is further filtered and purified.

[0045] Step S5: Mining the overlying coal in the priority mining area 6 of the uranium ore: After the uranium ore mining is completed, the injection well 19, pumping well 20, and monitoring well 21 will be permanently sealed. Based on the preparation roadway of the priority mining area 6 of the uranium ore, the coal mine production system in this area will be improved, and the coal seam above the uranium ore in the priority mining area 6 will be mined. During coal mining, floor grouting reinforcement will be carried out to seal any possible water-conducting cracks in the floor and further prevent floor water inrush.

[0046] After the mining of coal seam 1 is completed, one method for mining coal seam 25, which is covered by uranium ore, is to use a backfilling method, such as... Figure 5 As shown. The specific method of backfilling mining involves injecting backfill materials 26, such as solids, pastes, or high-water-content materials, into the goaf formed after coal seam mining. This controls the migration of overlying strata and prevents the formation of inter-strata fractures that could cause pollutants 27 from the groundwater in the decommissioned uranium mine to migrate to the lower coal face. Another approach is to employ disruptive mining technologies, such as in-situ unmanned coal mining, to mine the coal seam 25 overlying the uranium mine after the completion of mining of this coal seam 1. Examples include underground coal gasification and in-situ microbial hydrogen production from coal. Figure 6 As shown, microbial solution 29 is injected in situ into the coal seam 25 overlaid by uranium ore through injection well 28, forming a coal microbial gas production reaction zone 31 in the coal seam fracture network 30. Clean energy sources such as hydrogen and methane are produced through microbial leaching, and the gaseous products are pumped to the surface through extraction well 32. Oxygen and supercritical water are injected through injection well 28, igniting the coal gasification reaction in the horizontal well, thereby producing methane, which is also pumped to the surface through extraction well 32. In-situ unmanned coal mining avoids safety issues at the source.

[0047] S6. After the overlying coal mining of the uranium mine is completed, the coal in protected area 5 will be mined. Since the coal in coal mining area 4 and the priority mining area 6 of the uranium mine have already been mined when the coal in protected area 5 is mined, the overlying strata will cause stress accumulation on the coal and rock in protected area 5, which is prone to triggering disasters such as rock bursts. Therefore, the surrounding rock control and disaster early warning during the mining process in protected area should be strengthened.

[0048] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited thereto. Various changes that can be made within the scope of knowledge possessed by those skilled in the art without departing from the spirit of the present invention are all within the protection scope of the claims of the present invention.

Claims

1. A method for co-mining coal and associated uranium ore, characterized in that, Includes the following steps: S1. Conduct geological exploration: Collect geological and hydrological information of the mining area through exploration drilling in the coal-uranium co-mining area; S2. Divide the mining area: Divide the coal mine field into three areas according to whether it overlaps with uranium mines. One wing of the mine field is the coal-uranium overlap area, which is the priority mining area for uranium mines. The other wing is the coal mining area where the coal seams do not overlap with uranium mines. The middle of the two wings is the protection area. S3. Establish coal mine production system and uranium mine production system: construct vertical shafts to the coal seam, and excavate preparatory roadways in the coal mining area and the uranium priority mining area respectively; form a complete coal mining system in the coal mining area, and construct injection wells, pumping wells and monitoring wells in the track roadways of the uranium priority mining area to the uranium-bearing aquifer to form a uranium mining system. S4. Mining coal and uranium: mining coal in the coal mining area and simultaneously leaching uranium in the priority mining area of ​​uranium, using the coal mining roadway excavated in step S3 to transport the leaching solution. S5. Mining coal in the priority mining area of ​​uranium mine: After the uranium mine is completed, the pumping, injection wells and monitoring wells will be permanently sealed; based on the preparation roadway in the priority mining area of ​​uranium mine, the coal mine production system in the area will be improved, and the overlying coal seam of uranium mine will be mined; after the overlying coal seam is mined, the coal seam under the uranium mine will be mined. S6. Mining coal in the protected area: After the uranium mine overlying coal seam is completed, tunnels are excavated in the coal seam of the protected area to mine the coal seam in the protected area.

2. The method for co-mining coal and associated uranium ore according to claim 1, characterized in that, In step S1, the geological and hydrological information of the mining area specifically includes: the occurrence characteristics and distribution range of coal and associated uranium, the physical and mechanical properties of coal seams and their top and bottom plates as well as the water level and head of the mineralized aquifers.

3. The method for co-mining coal and associated uranium ore according to claim 1, characterized in that, In step S2, the method for establishing the protected area is as follows: using the rock physical and mechanical property parameters measured in step S1, through numerical simulation and physical similarity simulation methods, the evolution law of coal seam mining-induced fractures and the distribution characteristics of mining-induced rock stress field are obtained, and the range of disturbance of coal mining to the surrounding rock mass is determined, which is the range of the protected area.

4. The method for co-mining coal and associated uranium ore according to claim 1, characterized in that, In step S3, a suitable drilling spacing is determined based on the hydrogeological conditions obtained from exploration; according to the layout of the coal mine preparation roadway, the uranium mine drilling is designed as inclined shafts at different angles, and the number of inclined shafts varies with the width of the working face; the inclined shafts are used to increase the coverage area of ​​the uranium reservoir by the drilling, reduce the spacing between the uranium reservoir injection points, and thus improve the resource recovery rate.

5. The method for co-mining coal and associated uranium ore according to claim 1, characterized in that, In step S3, based on the layout of the coal mine preparation roadway, the uranium mine drilling is designed as an "L-shaped" horizontal well. The middle horizontal well is used to inject leaching solution, and the horizontal wells on both sides are used to extract leaching solution. The leaching solution is extracted and injected using the orifices in the horizontal well section. The horizontal well is used to increase the contact area between the leaching point of the leaching solution and the uranium reservoir, thereby improving the leaching extraction efficiency.

6. The method for co-mining coal and associated uranium ore according to claim 1, characterized in that, In step S4, the pumping route of the uranium ore leaching solution is: surface industrial area → auxiliary shaft → bottom shaft yard → main track roadway → track uphill → track level roadway → injection well. The extraction route of the leaching solution is the opposite of the pumping route. After being pumped to the surface, it is further filtered and purified.

7. The method for co-mining coal and associated uranium ore according to claim 1, characterized in that, In step S5, during the mining of the coal seam overlying the uranium mine, grouting is carried out to reinforce the bottom plate and seal any water-conducting cracks that may occur, further preventing water inrush from the bottom plate.

8. The method for co-mining coal and associated uranium ore according to claim 1, characterized in that, In step S5, the uranium ore overlying coal seam is mined using a backfilling method. Specifically, solid, paste, or high-water-content materials are filled into the goaf to control the migration of the overlying strata and prevent the formation of interlayer fissures that would cause pollutants in the groundwater of the decommissioned uranium mine to migrate to the coal face below.

9. The method for co-mining coal and associated uranium ore according to claim 1, characterized in that, In step S5, the uranium ore-covered coal seam is subjected to in-situ unmanned coal mining, including underground coal gasification and in-situ microbial hydrogen production from coal.

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