In-situ sealed leaching-adsorption circulation process for underground ore bodies

Abstract

This invention relates to an in-situ sealed leaching-adsorption circulation process for underground ore bodies. Based on an in-situ embedded leaching-adsorption circulation system, it is used to complete the adsorption enrichment of leachate and the closed-loop regeneration of leachate in the mining layer of an underground ore body. The in-situ embedded leaching-adsorption circulation system includes an underground sealed pipeline moving bed, a leachate collection device, and a lean solution reuse device. The underground sealed pipeline moving bed includes a sealed storage tank, a central double pipe, and a lower liquid inlet tank. The method is as follows: 1. Constructing an in-situ crushed ore pile: A. Excavating a pit at the lower end of the mining layer; B. Creating a false bottom at the bottom of the pit; C. Blasting the mining layer to form an ore pile; 2. Leaching and extraction of rich solution; 3. Conversion between rich and lean solution; 4. Regeneration and reuse of leachate. This invention is used to complete the adsorption enrichment of leachate and the closed-loop regeneration of leachate in the mining layer of an underground ore body.

Description

Technical Field

[0001] This invention relates to the field of hydrometallurgical technology for uranium ore, and in particular to an underground in-situ adsorption treatment method for leaching solutions in in-situ blasting leaching processes, especially an in-situ sealed leaching-adsorption cycle process for underground ore bodies. Background Technology

[0002] In-situ blasting leaching is currently the mainstream mining technology for low-grade uranium ore. The core operation involves in-situ blasting of the underground ore body to break it into a fragmented ore heap with a certain size. Leaching solution is then sprayed into the fragmented ore heap to selectively dissolve uranium minerals and obtain a leaching solution containing uranyl complexes (rich solution). Finally, the rich solution is pumped back to the surface for recovery.

[0003] In-situ blasting leaching technology heavily relies on a channel system within the underground ore body to transport the liquid. This channel system includes vertical shafts and multiple horizontal tunnels excavated horizontally. All horizontal tunnels extend in the same direction and are aligned vertically; one end of each horizontal tunnel connects to a different depth within the vertical shaft, and the other end connects to a corresponding mining layer. Within the underground ore body, the area between any two horizontal tunnels, the ore body area above the uppermost horizontal tunnel, or the ore body area below the lowermost horizontal tunnel constitutes a mining layer, thus forming multiple mining layers separated from top to bottom by different horizontal tunnels.

[0004] A supporting ion exchange moving bed and leaching solution preparation device needs to be constructed on the surface of the mining area. The leaching solution is prepared in the preparation device and pumped underground through pipelines buried in vertical shafts and horizontal tunnels. It is then evenly sprayed onto the in-situ crushed ore pile, selectively dissolving uranium minerals to obtain a leaching solution (rich solution) containing uranyl complexes. This rich solution is then pumped back to the surface through pipelines buried in vertical shafts and horizontal tunnels and fed into the moving bed for the adsorption and enrichment of uranyl complexes. The moving bed adsorbs the uranyl complexes in the rich solution through resin microspheres (based on an ion exchange process) within its internal cavity. Saturated resin microspheres (i.e., resin microspheres reaching maximum adsorption capacity) are discharged from the bottom of the moving bed, while lean solution (obtained by depleting the rich solution) is discharged from the middle or upper part of the moving bed. The saturated resin microspheres are then acid-washed and desorbed to obtain regenerated lean resin and qualified leaching solution. The lean solution is then acid-added and prepared to obtain the leaching solution used for spraying the in-situ crushed ore pile.

[0005] Traditional in-situ explosive leaching processes have the following shortcomings:

[0006] 1. High environmental safety risks: Pipelines for transporting leachate (rich solution) and leaching solution over long distances can reach hundreds of meters in total length, and the risk of leakage is relatively high. If a leakage occurs, it will pollute the surface water and soil.

[0007] 2. High energy consumption and time costs: The leachate is prepared on the ground and then sent to the in-situ crushed ore pile underground. The rich solution leached from the in-situ crushed ore pile needs to be pumped to the surface for treatment. The liquid transportation path is long, resulting in a combination of energy consumption and time costs.

[0008] 3. Risk of surface exposure: Although underground mining is widespread, ion exchange adsorption technology still relies on surface facilities. The so-called "undergrounding" is limited to the mining stage. The rich solution leached from the ore body and pumped to the surface will form an indelible surface signal source. In addition, large adsorption tower groups on the surface (height > 15m) will form heat source shapes with unique geometric features, which are easily identified by multispectral satellites. Furthermore, the surface pipeline network generates periodic heat tracks, which can easily expose the production scale and process route. Finally, surface fixed facilities are likely to become the first target in a conflict. Summary of the Invention

[0009] The purpose of this invention is to overcome the shortcomings of the prior art and provide an in-situ sealed leaching-adsorption circulation process for underground ore bodies. The process is based on an in-situ embedded leaching-adsorption circulation system for underground ore bodies. It solves the problems of long liquid transport paths, relatively high leakage risks, superimposed energy and time costs, and the risk of surface exposure in traditional in-situ blasting leaching processes.

[0010] The technical solution of this invention is: an in-situ sealed leaching-adsorption cycle process for underground ore bodies, based on an in-situ embedded leaching-adsorption cycle system for underground ore bodies, used to complete the adsorption enrichment of leaching solution and closed-loop regeneration of leaching solution in situ at the mining layer of underground ore bodies.

[0011] The underground ore body is equipped with a channel system, which includes vertical shafts and multiple horizontal tunnels excavated in the horizontal direction. All horizontal tunnels extend in the same direction and are directly opposite each other. The front end of each horizontal tunnel is connected to a different depth position of the vertical shaft. The ore body area between the rear ends of any two horizontal tunnels is the mining layer. After the mining layer is blasted, an in-situ crushed ore pile is formed. Between the middle sections of any two adjacent horizontal tunnels, an installation channel is drilled in the vertical direction. The installation channel includes an upper installation hole and a lower installation hole connected in sequence.

[0012] The underground ore body in-situ embedded leaching-adsorption circulation system includes an underground sealed pipeline moving bed, a leaching solution collection device, and a lean solution reuse device;

[0013] The underground sealed pipeline moving bed includes a sealed storage tank, a central double pipe, and a lower liquid inlet tank connected sequentially from top to bottom. The sealed storage tank has an inner cavity A, and a lean liquid discharge pipe is sealed and installed on the side or top wall of the sealed storage tank. A resin drop outlet is located at the bottom of the sealed storage tank. The central double pipe includes an outer pipe and an inner pipe fixedly installed inside the outer pipe. A ring-shaped interlayer is formed between the inner and outer pipes, and the upper end of the ring-shaped interlayer connects to the resin drop outlet. The outer pipe includes a drop pipe, a conical pipe, and an impregnation material connected sequentially from top to bottom. The inner tube consists of a discharge pipe, a resin discharge port, and a screen pipe connected sequentially from top to bottom. The discharge pipe is installed in the inner hole of the discharge pipe. The lower inlet tank has an inner cavity B and a connecting port at the upper end, which is fixedly connected to the lower end of the impregnation pipe. The bottom of the lower inlet tank has a saturated resin outlet, and the side wall of the lower inlet tank has a rich liquid input pipe. The underground sealed pipeline moving bed is fixedly installed in the target installation channel and two horizontal tunnels connected at its upper and lower ends.

[0014] The leachate collection device includes a extraction pipe, a leachate collection tank, and extraction pump A. The leachate collection tank is installed in the lower horizontal roadway, with a leachate inlet and a leachate outlet at its upper and lower ends, respectively. The front end of the extraction pipe extends into the in-situ crushed ore pile, the rear end of the extraction pipe is connected to the leachate inlet, and the leachate outlet is connected to the outer end of the rich solution input pipe. Two extraction pumps A are respectively located between the leachate collection tank and the rich solution input pipe, and between the leachate collection tank and the rear end of the extraction pipe.

[0015] The lean liquor reuse device includes a leachate mixing tank, a spray pipe, an interlayer pipe, and a pump B. The leachate mixing tank is installed in the upper horizontal roadway, with a lean liquor recovery port and an acid addition port at its upper end. The lower end of the leachate mixing tank has a leachate outlet with a valve, and the lean liquor recovery port is connected to the outer port of the lean liquor discharge pipe. The spray pipe is located directly above the in-situ crushed ore pile, with an inlet and an outlet at each end, the outlet facing the in-situ crushed ore pile. The upper port of the interlayer pipe is connected to the leachate outlet, and the lower port of the interlayer pipe passes through the upper horizontal roadway, the vertical shaft, and the lower horizontal roadway in sequence, and is connected to the inlet. Two pumps B are respectively located between the leachate mixing tank and the lean liquor discharge pipe, and between the inlet of the spray pipe and the lower port of the interlayer pipe.

[0016] The method is as follows:

[0017] S01, Construct an in-situ crushed ore pile:

[0018] A. A mine pit is excavated at the lower end of the mining layer;

[0019] B. Create a false bottom at the bottom of the mine pit;

[0020] C. Blasting the mining layer forms a ore pile;

[0021] SO2, leaching and extraction of rich solutions:

[0022] The leaching solution prepared in the leaching solution preparation tank is sprayed onto the in-situ crushed ore pile through the cross-layer pipe and spray pipe under the drive of the leaching pump B. The in-situ crushed ore pile leaches a rich solution containing uranyl complex. The rich solution is then pumped through the leaching pipe to the leaching solution collection tank under the drive of the leaching pump A, and then fed into the inner cavity B of the lower inlet tank through the rich solution input pipe.

[0023] S03, the conversion between rich and poor solutions:

[0024] After the rich solution enters the lower inlet tank, the following two events occur simultaneously:

[0025] I. Unsaturated resin microspheres are dominated by the drag force of the rising liquid flow and are distributed in the upper part of the inner cavity B. Saturated resin microspheres are dominated by gravity and settle and accumulate at the bottom of the inner cavity B, eventually forming a "three-layer structure" in the inner cavity B.

[0026] II. During the upward process, the rich solution comes into countercurrent contact with the unsaturated resin microspheres. The uranyl complex in the rich solution is adsorbed by the unsaturated resin microspheres, causing the rich solution to gradually become a lean solution. Under the combined action of the static pressure difference between the liquid level inside and outside the screen tube and the suction force of the pump B, the lean solution enters the screen tube and then passes through the delivery pipe, the connecting pipe and the lean solution discharge pipe in sequence, and enters the leachate preparation tank.

[0027] S04, Regeneration and reuse of leachate:

[0028] Acid is added to the leaching solution preparation tank through the acid addition port to regenerate the lean solution into leaching solution. The pump B is then started to discharge the leaching solution from the leaching solution outlet of the leaching solution preparation tank. The leaching solution is then sprayed onto the in-situ crushed ore pile through the interlayer pipe and spray pipe to achieve the regeneration and reuse of the leaching solution.

[0029] A further technical solution of the present invention is as follows: Step S01 is described in detail below:

[0030] A. Excavating a pit at the lower end of the mining layer: Define two adjacent horizontal roadways above and below the target mining layer as the upper horizontal roadway and the lower horizontal roadway, respectively. The target mining layer is located between the rear end of the upper horizontal roadway and the rear end of the lower horizontal roadway. In the lower horizontal roadway at the lower end of the target mining layer, excavate a pit of a certain depth as a reserved space for blasting compensation.

[0031] B. Construct a false bottom at the bottom of the mine: Construct a false bottom at the bottom of the mine for load-bearing purposes, and lay a base with a water-proof effect on the upper surface of the false bottom. The false bottom is used to receive the crushed ore that will collapse during subsequent blasting of the target mining layer.

[0032] C. Formation of ore pile by blasting mining layer: The target mining layer is blasted in situ, and the broken ore that falls from the blast naturally falls on the base above the false bottom, thus forming an in-situ broken ore pile.

[0033] A further technical solution of the present invention is as follows: In an underground sealed pipeline type moving bed, the outer pipe is vertically fixed in the target installation channel by a casting process, the upper end of the outer pipe extends into the horizontal tunnel connected to the upper end of the target installation channel, and the lower end of the outer pipe extends into the horizontal tunnel connected to the lower end of the target installation channel; the sealed storage tank is installed in the horizontal tunnel connected to the upper end of the target installation channel; and the lower liquid inlet tank is installed in the horizontal tunnel connected to the lower end of the target installation channel.

[0034] A further technical solution of the present invention is: the top of the sealed storage tank is provided with an atmospheric vent, a compressed air injection port and a sealed feeder; the atmospheric vent and the compressed air injection port are in a sealed and normally closed state;

[0035] In step S03, during the operation of the underground sealed pipeline moving bed, as more and more unsaturated resin microspheres are transformed into saturated resin microspheres, the saturated resin microspheres sink and accumulate at the bottom of the lower inlet tank cavity B. The gaps in the sealed storage tank cavity A and the annular interlayer also gradually increase, and the air pressure in the sealed storage tank cavity A and the annular interlayer gradually decreases, thereby causing the rich liquid level to rise continuously. In order to keep the rich liquid level within the range of "submerging the screen tube and not entering the annular interlayer", the atmospheric vent at the top of the sealed storage tank is opened periodically to allow a certain amount of outside air to enter the sealed storage tank cavity A and the annular interlayer.

[0036] In step S03, during the operation of the underground sealed pipeline moving bed, if the resin microspheres in the annular interlayer become stuck together, compressed air is injected into the inner cavity A of the sealed storage tank and the annular interlayer through the compressed air injection port to push the stuck resin microspheres downwards, so that the stuck resin microspheres enter the annular interval between the outer wall of the screen tube and the inner wall of the impregnation tube.

[0037] In step S03, during the operation of the underground sealed pipeline moving bed, the valve on the saturated resin outlet at the bottom of the lower liquid inlet tank is opened to discharge the saturated resin microspheres accumulated at the bottom of the inner cavity B of the lower liquid inlet tank, thus obtaining the product of the closed-loop process.

[0038] A further technical solution of the present invention is: the length of the screen tube is 1-4m, the outer diameter of the screen tube is 75-85mm, and the inner diameter of the impregnation tube is 390-410mm.

[0039] A further technical solution of the present invention is as follows: the material discharge pipe is formed by sequentially threading together multiple short material discharge pipes with a length between 0.8 and 1.2 m, and the length of the material discharge pipe exceeds the length of the upper mounting hole by 0.2-0.5 m; the liquid delivery pipe is formed by sequentially threading together multiple short liquid delivery pipes with a length between 0.8 and 1.2 m, and the upper end of the uppermost short liquid delivery pipe exceeds the height of the upper end of the material discharge pipe by 0.1-0.2 m.

[0040] A further technical solution of the present invention is: multiple axially extending strip grooves are provided at the lower end of the immersion tube, and the upper end of each axially extending strip groove is connected to a circumferentially arranged arc groove; multiple axially extending axial mounting grooves are provided in the inner hole of each short discharge tube, and the direction of the axial mounting grooves extends from the upper end of the short discharge tube to the lower end, but does not penetrate to the lower end of the short discharge tube.

[0041] The inner tube is fixedly installed in the inner hole of the outer tube by a positioning assembly; the positioning assembly includes an end face support plate and multiple center positioning plates; the end face support plate is fixedly installed in the inner hole of the immersion tube, and the center positioning plates are installed in the inner hole of the discharge short tube;

[0042] The end face support plate includes a center plate and multiple support plates A connected to the outside of the center plate. A fan-shaped perforation is formed between two adjacent support plates A to allow resin microspheres to pass through. The number of support plates A is consistent with the number of axial strip grooves and corresponds one-to-one. The number of support plates A is consistent with the number of circumferential arc grooves and corresponds one-to-one. The end face support plate slides into the inner hole of the impregnation tube from the lower end opening through the sliding fit between the support plates A and the axial strip grooves of the impregnation tube. When the end face support plate is pushed to the junction of the axial positioning groove and the circumferential arc groove of the impregnation tube, the end face support plate is rotated so that the support plates A on the end face support plate enter the corresponding circumferential arc groove in the inner hole of the impregnation tube, thus realizing the fixed installation of the end face support plate in the inner hole of the impregnation tube.

[0043] The number of centering positioning plates corresponds one-to-one with the number of short discharge tubes in the discharge tube. The centering positioning plate includes an annular plate and multiple support plates B connected to the outside of the annular plate. A fan-shaped perforation is formed between two adjacent support plates B402 to allow resin microspheres to pass through. A through hole B is provided at the center of the annular plate for the liquid delivery short tube to slide through. A chamfer is provided at the upper end of the through hole B to guide the insertion of the pipe. The centering positioning plate is slidably pushed into the inner hole of the short discharge tube from the upper end of the discharge tube through the sliding fit between the support plate B and the axial mounting groove. The chamfer on the centering positioning plate faces the upper end of the discharge tube. When the centering positioning plate is pushed to the bottom of the axial mounting groove, the installation of the centering positioning plate in the inner hole of the short discharge tube is achieved.

[0044] Compared with the prior art, the present invention has the following advantages:

[0045] 1. The described process is used to complete the adsorption and enrichment of leachate and the closed-loop regeneration of leachate in situ within the mining layer of an underground ore body. The process relies on an in-situ embedded leaching-adsorption circulation system within the underground ore body. The underground sealed pipeline moving bed is the core component of the circulation system, used for the adsorption and enrichment of leachate. All components of the underground sealed pipeline moving bed are modular components, with any adjacent components connected by threads or flanges, facilitating assembly and transportation. With specific installation methods, it can meet the installation requirements in narrow underground ore body passage systems.

[0046] 2. Compared with traditional surface moving beds, underground sealed pipeline moving beds do not require the construction of surface facilities. The adsorption and enrichment of uranium ore leaching solution (rich solution) is completed in situ in the underground ore body (saturated resin is collected in the lower horizontal tunnel and then transported to the surface through the vertical shaft), which meets the strategic concealment requirements.

[0047] 3. The underground sealed pipeline type moving bed is installed between the upper and lower level roadways corresponding to the target mining layer, realizing in-situ installation of the underground ore body. Compared with the traditional surface moving bed, the underground sealed pipeline type moving bed significantly reduces the length of the pipeline for transporting leachate (rich solution) and leaching solution (the transport path of the traditional surface moving bed is: surface-underground ore pile, with a pipeline length of up to hundreds of meters; the transport path of the underground sealed pipeline type moving bed is: in-situ crushed ore pile-upper or lower level roadway, with a pipeline length of only tens of meters), reducing transport energy consumption, transport time and leakage risk.

[0048] 4. The height of the underground sealed pipe moving bed is comparable to that of the mining layer, about 30-40m, which is much higher than that of the traditional surface moving bed (about 20m). Moreover, most of the height of the underground sealed pipe moving bed is contributed by the central double pipe. The central double pipe is a slender pipe structure. The only space inside the central double pipe is the annular column interlayer for the resin microspheres to circulate. Therefore, the control of the liquid level inside the moving bed is very important (the liquid level should be prevented from rising to the narrow annular column interlayer as much as possible, which would cause the resin microspheres to absorb water, resulting in adhesion, caking, or even blockage of the annular column interlayer). To solve this problem, the technical approach adopted is as follows: the inner cavity A of the sealed storage tank is designed as a sealed space to ensure that there is no air leakage. This prevents the air in the inner cavity A of the sealed storage tank and the annular interlayer from being squeezed out due to the rise of the liquid level in the inner cavity B of the lower liquid inlet tank. Under the suction action of the liquid pump B and the effect of the static pressure difference between the liquid level inside and outside the screen tube, the rich liquid level is ultimately within the range of "submerging the screen tube but not entering the annular interlayer". This effectively avoids the resin microspheres in the annular interlayer from being wetted by the liquid and causing adhesion, caking, or even blockage of the annular interlayer.

[0049] The present invention will be further described below with reference to the figures and embodiments. Attached Figure Description

[0050] Figure 1 A schematic diagram of the structure and installation of an in-situ embedded leaching-adsorption circulation system for underground ore bodies;

[0051] Figure 2 for Figure 1 Enlarged view of part E;

[0052] Figure 3 for Figure 1 Enlarged view of part F;

[0053] Figure 4 This is a schematic diagram of the structure of the present invention;

[0054] Figure 5 for Figure 4 Enlarged view of part A;

[0055] Figure 6 for Figure 5 BB cross-sectional view;

[0056] Figure 7 for Figure 4 Enlarged view of part C;

[0057] Figure 8 for Figure 4 Enlarged view of part D;

[0058] Figure 9 This is a structural schematic diagram of the end face support plate;

[0059] Figure 10 This is a diagram showing the installation status of the end face support plate.

[0060] Legend: Sealed storage tank 1; Inner cavity A11; Atmospheric vent 12; Compressed air injection port 13; Sealed feeder 14; Lean liquor discharge pipe 15; Resin drop port 16; Inner pipe 2; Connecting pipe 21; Liquid delivery pipe 22; Screen pipe 23; Outer pipe 3; Drop pipe 31; Axial mounting groove 311; Conical pipe 32; Impregnation pipe 33; Axial strip groove 331; Circumferential arc groove 332; Lower liquid inlet tank 4; Inner cavity B41; Connecting port 42; Saturated resin outlet 43; Rich liquor input pipe 44; Vertical shaft 51; Horizontal roadway 52; Mining layer 53; Installation channel 54; Upper mounting hole 541; Lower Mounting hole 542; Annular stepped surface 543; In-situ crushed ore pile 55; False bottom 56; Extraction pipe 71; Leachate collection tank 72; Leachate inlet 721; Leachate outlet 722; Extraction pump A73; Leachate mixing tank 81; Lean solution recovery port 811; Acid addition port 812; Leachate outlet 813; Spray pipe 82; Interlayer pipe 83; Extraction pump B84; Annular column interlayer 100; Annular column interval 200; End face support plate 300; Center plate 301; Leg plate A302; Centering positioning plate 400; Annular plate 401; Annular plate 401; Leg plate B402; Chamfer 403. Detailed Implementation Example 1

[0061] like Figure 1-10 As shown, the in-situ embedded leaching-adsorption circulation system of the underground ore body includes an underground sealed pipeline moving bed, a leaching solution collection device, and a lean solution reuse device.

[0062] The term "leaching" refers to the process where the in-situ crushed ore pile 55 is dissolved by the leachate to generate a leachate (rich solution). "Adsorption" refers to the process where the leachate (rich solution) enters the underground sealed pipe-type moving bed and comes into countercurrent contact with resin microspheres. The uranyl complexes in the leachate (rich solution) are adsorbed onto the resin microspheres, thus transforming the leachate (rich solution) into a lean solution, which is then discharged from the underground sealed pipe-type moving bed. The term "circulation" is reflected in the closed-loop transformation: "Leachate (rich solution) generated in the in-situ crushed ore pile - Leachate (rich solution) enters the underground sealed pipe-type moving bed and transforms into lean solution - Lean solution enters the leachate mixing tank 81 and is mixed into leachate - Leachate is sprayed onto the in-situ crushed ore pile to generate leachate (rich solution)".

[0063] The underground ore body is equipped with a passage system, which includes (but is not limited to) a vertical shaft 51 and multiple horizontal tunnels 52 excavated in the horizontal direction. All horizontal tunnels 52 extend in the same direction and are vertically aligned. The front end of each horizontal tunnel 52 connects to different depths of the vertical shaft 51. The ore body area between the rear ends of any two horizontal tunnels 52 is a mining layer 53, thus forming multiple mining layers 53 separated from top to bottom by different horizontal tunnels 52. After blasting, the mining layer 53 forms an in-situ crushed ore pile 55. Between the middle sections of any two vertically adjacent horizontal tunnels 52, an installation channel 54 is drilled vertically. The installation channel 54 includes an upper installation hole 541 and a lower installation hole 542 connected in sequence. The cross-sectional area of ​​the lower installation hole 542 is larger than that of the upper installation hole 541, thus forming an annular step surface 543 between the upper installation hole 541 and the lower installation hole 542. The two horizontal tunnels 52 connecting the upper and lower ends of the target installation channel 54 are defined as the upper horizontal tunnel and the lower horizontal tunnel, respectively.

[0064] The underground sealed pipeline moving bed includes a sealed storage tank, a middle double pipe and a lower liquid inlet tank connected in sequence from top to bottom.

[0065] The sealed storage tank 1 has an internal cavity A11 for storing resin microspheres. The top of the sealed storage tank 1 has an atmospheric vent 12, a compressed air injection port 13, and a sealed feeder 14. Sealing plugs (not shown in the figure) are movably installed on the atmospheric vent 12 and the compressed air injection port 13. Based on the sealing effect of the sealing plugs, the atmospheric vent 12 and the compressed air injection port 13 are normally closed and sealed. The sealing plugs are only removed when performing specific operations (for example, when it is necessary to balance the air pressure between the inner cavity A11 of the sealed storage tank 1 and the outside, the sealing plug on the atmospheric vent 12 is removed; when it is necessary to push down the resin microspheres inside the central double tube, the sealing plug on the compressed air injection port 13 is removed, and then the air outlet pipe of the air compressor (an external device) is connected to the compressed air injection port 13). The sealed feeder 14 is used to add dried resin microspheres to the inner cavity A11 of the sealed storage tank 1. The side wall or top wall of the sealed storage tank 1 has a through-hole A (not shown in the figure). A lean liquid discharge pipe 15 with a valve is sealed and installed in the pipe hole A. The inner and outer ends of the lean liquid discharge pipe 15 are located in the inner cavity A11 of the sealed storage tank 1 and the outside of the sealed storage tank 1, respectively. The bottom of the sealed storage tank 1 is provided with a resin drop outlet 16.

[0066] The central double-tube configuration includes an outer tube 3 and an inner tube 2 centrally and fixedly installed inside the outer tube 3 (the term "centrally" is defined as the inner tube 2 and the outer tube 3 having their centerlines coincide). An annular interlayer 100 is formed between the inner tube 2 and the outer tube 3 to accommodate resin microspheres. The annular interlayer 100 is directly connected at its upper end to the resin discharge port 16 of the sealed storage tank 1. The outer tube 3 is a rigid tube with open ends. The outer tube 3 includes a discharge pipe 31, a tapered pipe 32, and an impregnation pipe 33 connected sequentially from top to bottom. The outer diameter of the discharge pipe 31 is smaller than the outer diameter of the impregnation pipe 33, and the inner diameter of the discharge pipe 31 is smaller than the inner diameter of the impregnation pipe 33. The upper end of the discharge pipe 31 is fixedly connected to the resin discharge port 16 of the sealed storage tank 1. The tapered pipe 32 connects the discharge pipe 31 and the impregnation pipe 33, serving as a transition in pipe diameter between them. The inner tube 2 includes a connecting pipe 21, a liquid delivery pipe 22, and a screen pipe 23 connected sequentially from top to bottom. The liquid delivery pipe 22 is a rigid pipe with open ends. The liquid delivery pipe 22 is installed in the inner hole of the discharge pipe 31. The annular interlayer 100 is located between the outer surface of the liquid delivery pipe 22 and the inner wall of the discharge pipe 31. The upper end of the liquid delivery pipe 22 passes through the resin discharge port 16 of the sealed storage tank 1 and enters the inner cavity A11 of the sealed storage tank 1. The lower end of the liquid delivery pipe 22 passes through the lower end orifice of the discharge pipe 31 and enters the inner hole of the tapered tube 32. The screen pipe 23 is a rigid pipe with an open upper end and a closed lower end. The upper end of the screen pipe 23 is threaded to the lower end of the liquid delivery pipe 22. The outer surface of the screen pipe 23 is provided with water-permeable holes (not marked in the figure) smaller than the resin microspheres and evenly distributed. The upper and lower end faces of the screen pipe 23 do not extend beyond the upper and lower end faces of the impregnation pipe 33, respectively. The connecting pipe 21 is a flexible pipe with open ends. The two ends of the connecting pipe 21 are respectively sealed and connected to the inner port of the lean liquid discharge pipe 15 and the upper port of the liquid delivery pipe 22.

[0067] The lower inlet tank 4 has an internal cavity B41 for accommodating resin microspheres and rich liquid. The upper end of the lower inlet tank 4 has a connecting port 42, and the bottom of the lower inlet tank 4 has a saturated resin outlet 43 with a valve for discharging saturated resin microspheres. A rich liquid inlet pipe 44 is located on the side wall of the lower inlet tank 4. The inner and outer ends of the rich liquid inlet pipe 44 are located in the internal cavity B41 and outside the lower inlet tank 4, respectively. The outer port of the rich liquid inlet pipe 44 is used to input rich liquid, and the inner port of the rich liquid inlet pipe 44 is vertically downward for discharging rich liquid into the internal cavity B41 of the lower inlet tank 4. The connecting port 42 of the lower inlet tank 4 is fixedly connected to the lower port of the impregnation pipe 33. The rich solution from the outside is introduced into the inner cavity B41 of the lower inlet tank 4 through the rich solution inlet pipe 44, causing the liquid level in the inner cavity B41 to gradually rise. Since the density of unsaturated resin microspheres is less than that of water, they float on the upper layer of the rich solution. The unsaturated resin microspheres come into countercurrent contact with the continuously rising rich solution, and the resin microspheres adsorb uranyl complexes in the rich solution through ion exchange, thus gradually reaching saturation. The density of saturated resin microspheres is greater than that of water, so they sink and accumulate at the bottom of the inner cavity B41 of the lower inlet tank 4, thus ultimately forming a distinct "three-layer" structure: the bottom saturated resin layer, the middle lean solution layer, and the top unsaturated resin layer. In the unsaturated resin layer, the resin microspheres in the section where the screen tube 23 is located are all submerged in the rich solution, while the resin microspheres in the section where the delivery pipe 22 is located are dry unsaturated resin.

[0068] The underground sealed pipeline moving bed is fixedly installed in the target installation channel 54 and its two horizontal tunnels 52 (upper horizontal tunnel and lower horizontal tunnel) connected at their upper and lower ends. The number of underground sealed pipeline moving beds is consistent with the number of installation channels 54 and corresponds one-to-one. The outer pipe 3 is vertically fixed in the installation channel 54 by a casting process. The upper end of the outer pipe 3 (i.e., the upper port of the material drop pipe 31) extends into the upper horizontal tunnel, and the lower end of the outer pipe 3 (i.e., the lower port of the immersion pipe 33) extends into the lower horizontal tunnel. The sealed storage tank 1 is installed in the upper horizontal tunnel. The lower liquid inlet tank 4 is installed in the lower horizontal tunnel.

[0069] The leachate collection device includes a suction pipe 71, a leachate collection tank 72, and suction pumps A73. The leachate collection tank 72 is installed in the lower horizontal roadway, with a leachate inlet 721 and a leachate outlet 722 at its upper and lower ends, respectively. The front end of the suction pipe 71 extends into the in-situ crushed ore pile 55 located at the rear end of the lower horizontal roadway, and the rear end of the suction pipe 71 is connected to the leachate inlet 721 of the leachate collection tank 72. The leachate outlet 722 of the leachate collection tank 72 is connected to the outer end of the rich solution input pipe 44. Two suction pumps A73 are respectively installed between the leachate collection tank 72 and the rich solution input pipe 44, and between the leachate collection tank 72 and the rear end of the suction pipe 71, thereby drawing the leachate (rich solution) in the in-situ crushed ore pile 55 into the leachate collection tank 72, and pumping the leachate in the leachate collection tank 72 into the inner cavity B41 of the lower liquid inlet tank 4.

[0070] The lean leaching solution reuse device includes a leaching solution mixing tank 81, a spray pipe 82, a cross-layer pipe 83, and a pump B84. The leaching solution mixing tank 81 is installed in the upper horizontal roadway, with a lean leaching solution recovery port 811 and an acid addition port 812 at its upper end. The lower end of the leaching solution mixing tank 81 has a leaching solution outlet 813 with a valve. The lean leaching solution recovery port 811 of the leaching solution mixing tank 81 is connected to the outer port of the lean leaching solution discharge pipe 15. The spray pipe 82 is located directly above the in-situ crushed ore pile 55 at the rear end of the lower horizontal roadway. The spray pipe 82 has an inlet and an outlet at both ends, with the outlet of the spray pipe 82 facing the in-situ crushed ore pile 55, and is used to spray leaching solution onto the in-situ crushed ore pile 55. The upper end of the interlayer pipe 83 is connected to the leaching solution outlet 813 of the leaching solution preparation tank 81. The lower end of the interlayer pipe 83 passes through the upper horizontal tunnel, the vertical shaft, and the lower horizontal tunnel in sequence, and is connected to the inlet of the spray pipe 82. Two pumps B84 are respectively installed between the leaching solution preparation tank 81 and the lean solution discharge pipe 15, and between the inlet of the spray pipe 82 and the lower end of the interlayer pipe 83, so as to pump the lean solution discharged from the underground sealed pipeline moving bed into the leaching solution preparation tank 81, and to transport the leaching solution prepared in the leaching solution preparation tank 81 to the spray pipe 82.

[0071] Preferably, the lower end of the immersion tube 33 is provided with multiple axially extending strip grooves 331, and the upper end of each axially extending strip groove 331 is connected to a circumferentially arranged arc groove 332; the inner hole of each unloading short tube is provided with multiple axially extending mounting grooves 311, and the direction of the axial mounting grooves 311 is from the upper end of the unloading short tube to the lower end of the unloading short tube, but does not penetrate to the lower end of the unloading short tube.

[0072] The inner tube 2 is fixedly installed in the inner hole of the outer tube 3 by a positioning assembly. The positioning assembly includes an end face support plate 300 and multiple centering positioning plates 400. The end face support plate 300 is fixedly installed in the inner hole of the immersion tube 33, and the centering positioning plates 400 are installed in the inner hole of the discharge short tube.

[0073] The end face support plate 300 includes a center plate 301 and multiple support plates A302 connected to the outside of the center plate 301. A fan-shaped perforation is formed between adjacent support plates A302 to allow resin microspheres to pass through. The number of support plates A302 corresponds one-to-one with the number of axial strip grooves 331 and the number of support plates A302 corresponds one-to-one with the number of circumferential arc grooves. The end face support plate 300 connects to the axial strip grooves of the impregnation tube 33 via the support plates A302. The sliding fit relationship of 331 allows the plate to slide into the inner hole of the immersion tube 33 from the lower end opening. When the end face support plate 300 is pushed to the junction of the axial positioning groove 331 and the circumferential arc groove 332 of the immersion tube 33, the end face support plate 300 is rotated so that the support plate A302 on the end face support plate 300 enters the corresponding circumferential arc groove 332 in the inner hole of the immersion tube 33, thus realizing the fixed installation of the end face support plate 300 in the inner hole of the immersion tube 33.

[0074] The number of centering positioning plates 400 corresponds one-to-one with the number of short discharge tubes in the discharge tube 31. Each centering positioning plate 400 includes an annular plate 401 and multiple support plates B402 connected to the outside of the annular plate 401. A fan-shaped perforation is formed between two adjacent support plates B402 to allow resin microspheres to pass through. The annular plate 401 has a through hole B at its center for the liquid delivery tube to slide through. The upper end of the through hole B has a chamfer 403 for guiding the insertion of the tube. The centering positioning plate 400 is slidably pushed into the inner hole of the short discharge tube from the upper end of the discharge tube through the sliding fit between the support plates B402 and the axial mounting groove 221. The chamfer 403 on the centering positioning plate 400 faces the upper end of the discharge tube. When the centering positioning plate 400 is pushed to the bottom of the axial mounting groove 311, the centering positioning plate 400 is installed in the inner hole of the short discharge tube.

[0075] Preferably, the length of the screen tube 23 is 1-4m (2.5m is preferred), and the outer diameter of the screen tube 23 is 75-85mm (80mm is preferred). Correspondingly, the inner diameter of the immersion tube 33 is 390-410mm (400mm is preferred). The above three parameters together define a ring-shaped section 200 with a defined size. The length of the ring-shaped section 200 is the length of the screen tube 23, and the cross-sectional shape of the ring-shaped section 200 is an annulus formed by the outer wall of the screen tube 23 and the inner wall of the immersion tube 33. During the operation of the underground sealed pipeline moving bed, the resin microspheres within the annular column section 200 are immersed in the rich solution. The resin microspheres adsorb uranyl complexes from the rich solution through ion exchange, gradually increasing in density until they become saturated resin and settle. Simultaneously, the uranyl complexes in the rich solution are adsorbed onto the resin microspheres, becoming the lean solution. Under negative pressure (provided by a pump directly or indirectly connected to the external port of the lean solution discharge pipe 15, the lean solution enters the screen tube 23 and is discharged sequentially through the screen tube 23, the delivery pipe 22, the connecting pipe 21, and the lean solution discharge pipe 15 to the outside of the underground sealed pipeline moving bed. If the annular column section 200 is designed to be too small (screen tube 23 length less than 1m, immersion tube 33 inner diameter less than 390mm), the ion exchange efficiency will be low. If the annular column section 200 is designed to be too large (for example, the length of the screen tube 23 is greater than 4m and the inner diameter of the immersion tube 33 is greater than 410mm), then a lower mounting hole 542 with a larger diameter needs to be excavated to match it (which is equivalent to increasing the amount of excavation required for the lower mounting hole 542).

[0076] Preferably, the material discharge pipe 31 is formed by connecting multiple short material discharge pipes with a length between 0.8 and 1.2 m in sequence by threading. The length of the material discharge pipe 31 exceeds the length of the upper mounting hole 541 by 0.2-0.5 m.

[0077] Preferably, the liquid delivery pipe 22 is formed by connecting multiple short liquid delivery pipes with a length between 0.8 and 1.2 m in sequence by threading. The upper end of the uppermost short liquid delivery pipe extends 0.1-0.2 m above the upper end of the discharge pipe 31.

[0078] The in-situ sealed leaching-adsorption cycle process for underground ore bodies, based on the aforementioned in-situ embedded leaching-adsorption cycle system for underground ore bodies, is used to complete the adsorption enrichment of leachate and the closed-loop regeneration of leachate in situ within the mining layer of the underground ore body.

[0079] The method is as follows:

[0080] S01, Construct an in-situ crushed ore pile:

[0081] A. Excavation of a mining pit at the lower end of the mining layer: Two adjacent horizontal roadways above and below the target mining layer 53 are defined as the upper horizontal roadway and the lower horizontal roadway, respectively. The target mining layer 53 is located between the rear end of the upper horizontal roadway and the rear end of the lower horizontal roadway. In the lower horizontal roadway at the lower end of the target mining layer, a mining pit of a certain depth is excavated (the volume of the mining pit is 20% of the volume of the target mining layer) as a reserved space for blasting compensation. The excavated ore is transported to the surface through the lower horizontal roadway 52 and the vertical shaft 51.

[0082] B. Constructing a false bottom at the bottom of the mine: Constructing a false bottom 56 at the bottom of the mine for load-bearing purposes, and laying a base with a water-proof effect (preventing leachate (rich solution) seeping from the in-situ crushed ore pile 55 from seeping down to the bottom of the false bottom 56) on the upper surface of the false bottom 56. The false bottom 56 is used to receive the crushed ore that will collapse from the subsequent blasting of the target mining layer.

[0083] C. Formation of ore pile by blasting the mining layer: At the lower end of the target mining layer at the rear of the lower horizontal roadway, a network of blast holes is drilled upwards, and explosives are filled into the network of blast holes to blast the target mining layer 53 in situ. The broken ore that collapses from the blasting naturally falls on the base above the false bottom 56, thus forming an in-situ broken ore pile 55.

[0084] SO2, leaching and extraction of rich solutions:

[0085] The leaching solution prepared in the leaching solution preparation tank 81 is sprayed onto the in-situ crushed ore pile 55 through the interlayer pipe 83 and the spray pipe 82 under the drive of the pumping pump B84. The uranium minerals in the in-situ crushed ore pile 55 are dissolved, and a rich solution containing uranyl complex is leached out. The rich solution is pumped into the leaching solution collection tank 72 by the pumping pump A73, and then into the inner cavity B41 of the lower liquid inlet tank 4 through the rich solution inlet pipe.

[0086] In this step, the interlayer pipe 83 is entirely located within the underground ore body, and its path only includes the upper horizontal roadway-upper horizontal roadway in the shaft to the lower horizontal roadway at a height-lower horizontal roadway.

[0087] S03, the conversion between rich and poor solutions:

[0088] After the leachate (rich solution) enters the inner cavity B41 of the lower inlet tank 4, the liquid level in the inner cavity B41 gradually rises. When the leachate (rich solution) overflows the unsaturated resin microspheres, the following two events occur simultaneously:

[0089] I. Unsaturated resin microspheres are dominated by the drag force of the rising liquid flow and are distributed in the upper part of the inner cavity B41 of the lower liquid inlet tank 4. Saturated resin microspheres are dominated by gravity and settle and accumulate at the bottom of the inner cavity B41 of the lower liquid inlet tank 4, eventually forming a "three-layer structure" in the inner cavity B41 of the lower liquid inlet tank 4 (namely, the bottom saturated resin layer, the middle lean liquid layer, and the top unsaturated resin layer).

[0090] II. During the rising process, the leachate (rich solution) comes into countercurrent contact with the unsaturated resin microspheres in the upper part of the inner cavity B41 of the lower inlet tank 4. The uranyl complex in the leachate (rich solution) is adsorbed by the unsaturated resin microspheres, thereby gradually turning the leachate (rich solution) into a lean solution. Under the combined action of the static pressure difference between the liquid level inside and outside the screen tube 23 and the suction force of the pump B84 (located between the leachate preparation tank 81 and the lean solution discharge pipe 15), the lean solution passes through the water-permeable holes of the screen tube 23 and enters the inner hole of the screen tube 23. Then, it passes through the delivery pipe 22, the connecting pipe 21 and the lean solution discharge pipe 15 in sequence and enters the leachate preparation tank 81.

[0091] In this step, during the operation of the underground sealed pipeline moving bed, as more and more unsaturated resin microspheres transform into saturated resin microspheres, the saturated resin microspheres sink and accumulate at the bottom of the inner cavity B41 of the lower liquid inlet tank 4. The gaps in the inner cavity A11 of the sealed storage tank 1 and the annular interlayer 100 gradually increase, and the air pressure in the inner cavity A11 and the annular interlayer 100 of the sealed storage tank 1 gradually decreases, causing the rich liquid level to continuously rise. To maintain the rich liquid level within the range of "submerging the screen tube 23 without entering the annular interlayer 100," the atmospheric vent 12 at the upper end of the sealed storage tank 1 is opened periodically to allow a certain amount of outside air to enter the inner cavity A11 and the annular interlayer 100 of the sealed storage tank 1.

[0092] In this step, during the operation of the underground sealed pipeline moving bed, if the resin microspheres in the annular interlayer 100 become stuck together, compressed air is injected into the inner cavity A11 of the sealed storage tank 1 and the annular interlayer 100 through the compressed air injection port 13 to push the stuck resin microspheres downwards, so that the stuck resin microspheres enter the annular interval 200 between the outer wall of the screen tube 23 and the inner wall of the impregnation tube 33.

[0093] In this step, during the operation of the underground sealed pipeline moving bed, the valve on the saturated resin outlet 43 at the bottom of the lower liquid inlet tank 4 is opened to discharge the saturated resin microspheres accumulated at the bottom of the inner cavity B41 of the lower liquid inlet tank 4, thus obtaining the product of the closed-loop process.

[0094] S04, Regeneration and reuse of leachate:

[0095] Acid (e.g., H2SO4) is added to the leaching solution preparation tank 81 through the acid addition port 812 to adjust the pH to 1.5-2.0, thereby regenerating the lean solution into leaching solution. The pump B84 (located between the inlet of the spray pipe 82 and the lower port of the interlayer pipe 83) is then started. Driven by the pump B84, the leaching solution is discharged from the leaching solution outlet 813 of the leaching solution preparation tank 81, and then sprayed onto the in-situ crushed ore pile through the interlayer pipe 83 and the spray pipe 82, thereby realizing the closed-loop regeneration of the leaching solution.

[0096] Preferably, the method further includes an M step located between steps S01 and S02.

[0097] M. Installation of underground sealed pipe type mobile bed:

[0098] A. Transporting components to the assembly location: All components that make up the underground sealed pipeline moving bed are transported to the upper or lower horizontal tunnel via shaft 51, according to the installation location requirements. Specifically, all components that make up the inner pipe 2 and the material drop pipe 31 are transported to the upper horizontal tunnel, all the centering positioning plates 400 are transported to the upper horizontal tunnel, the tapered pipe 32, the immersion pipe 33, and the end face support plate 300 are transported to the lower horizontal tunnel, the sealed storage tank 1 is transported to the upper horizontal tunnel, and the lower liquid inlet tank 4 is transported to the lower horizontal tunnel.

[0099] B. Assembly and Casting of Fixed Outer Pipes: At the upper end of the mounting hole 541, in order from bottom to top, thread all the short drop pipes that make up the drop pipe 31 together and lower them vertically. During the connection process, a centering positioning plate 400 is installed in the inner hole of each drop pipe. (The process of installing the centering positioning plate 400 is as follows: before each drop pipe is connected to the upper drop pipe, and after the uppermost drop pipe is connected, a centering positioning plate 400 is installed.) 00 is inserted into the axial mounting groove 311 in the inner hole of the target short tube through the upper end orifice of the short tube, until all the short tubes are connected to form a complete short tube 31. At this time, the short tube 31 is located in the upper mounting hole 541. Ensure that the short tube 31 remains vertically centered in the upper mounting hole 541, so that a ring-shaped gap is formed between the outer surface of the short tube 31 and the inner wall of the upper mounting hole 541, and the upper and lower ends of the short tube 31 extend out of the upper mounting hole 541, respectively. Then, the short tube 31 is fixed in the upper mounting hole 541 by pouring cement mortar. At the lower end of the lower mounting hole 542, the tapered tube 32 is inserted into the lower mounting hole 542 and connected to the lower end of the drop tube 31. The immersion tube 33 is inserted into the lower mounting hole 542 and connected to the lower end of the tapered tube 32. At this time, both the tapered tube 32 and the immersion tube 33 are located in the lower mounting hole 542, thus completing the assembly and casting fixation of the outer tube 3.

[0100] C. Assembly and Limiting Installation of Inner Tube: At the upper end opening of the discharge pipe 31, all components constituting the inner tube 2 (screen pipe 23, all liquid delivery short pipes, and connecting pipe 21) are connected sequentially from bottom to top and lowered vertically. During the lowering process, the screen pipe 23 and all liquid delivery short pipes pass through the through holes B at the center of all the centering positioning plates 400 in sequence, thereby ensuring that the screen pipe 23 and all liquid delivery short pipes remain centered in the inner hole of the discharge pipe 31. When the lower end face of the screen pipe 23 abuts against the center plate 301 of the end face support plate 300, the limiting installation of the screen pipe 23 and the liquid delivery pipe 22 is completed. Then, the lower end of the connecting pipe 21 is connected to the upper end of the liquid delivery pipe 22, thus completing the assembly and limiting installation of the inner tube 2.

[0101] D. Connecting the sealed storage tank: Connect the sealed storage tank 1 located in the upper horizontal tunnel to the upper end of the middle double pipe, so that the upper end of the connecting pipe 21 is connected to the inner port of the lean liquid discharge pipe 15, and the upper port of the discharge pipe 31 is connected to the resin drop outlet 16. The specific operation is as follows: Move the sealed storage tank 1 located in the upper horizontal tunnel to directly above the outer pipe 3 and the inner pipe 2. First, send the upper end of the connecting pipe 21 into the inner cavity A11 of the sealed storage tank 1 through the resin drop port 16 of the sealed storage tank 1. Then, lower the sealed storage tank 1 until the resin drop port 16 at its lower end is directly opposite and in contact with the upper end face of the drop pipe 31. Next, seal and fix the resin drop port 16 of the sealed storage tank 1 to the upper end face of the drop pipe 31 (through flange and sealing ring), so that the inner cavity A11 of the sealed storage tank 1 is connected to the annular interlayer 100 (located between the inner pipe 2 and the outer pipe 3). Then, support the sealed storage tank 1 on the bottom surface of the upper horizontal tunnel. Next, open the top cover of the sealed storage tank 1 and connect the upper end of the connecting pipe 21 to the inner port of the lean liquid discharge pipe 15. Finally, reinstall the top cover of the sealed storage tank 1.

[0102] E. Connecting the lower inlet tank: Connect the lower inlet tank 4 located in the lower horizontal tunnel to the lower end of the middle double pipe, so that the lower port of the impregnation pipe 33 is connected to the interface 42. The lower end face of the resin discharge port 43 is left with a clearance height from the bottom surface of the lower horizontal tunnel for discharging saturated resin. The specific operation is as follows: Move the lower inlet tank 4 located in the lower horizontal tunnel to directly below the outer pipe 3 and the inner pipe 2. First, lift the lower inlet tank 4 upwards until the interface 42 at its upper end is directly opposite and attached to the lower port of the impregnation pipe 33. Then, seal and fix the interface 42 of the lower inlet tank 4 to the lower port of the impregnation pipe 33 (through flange and sealing ring), so that the annular interlayer 100 (located between the inner pipe 2 and the outer pipe 3) is connected to the inner cavity B41 of the lower inlet tank 4. Then, support the lower inlet tank 4 on the bottom surface of the lower horizontal tunnel. An open container for receiving saturated resin microspheres can be placed directly below the resin outlet 43.

Claims

1. In-situ sealed leaching-adsorption circulation process for underground ore bodies, based on an in-situ embedded leaching-adsorption circulation system for underground ore bodies, is used to complete the adsorption enrichment of leaching solution and closed-loop regeneration of leaching solution in situ at the mining layer of underground ore bodies. The underground ore body is equipped with a channel system, which includes vertical shafts and multiple horizontal tunnels excavated in the horizontal direction. All horizontal tunnels extend in the same direction and are directly opposite each other. The front end of each horizontal tunnel is connected to a different depth position of the vertical shaft. The ore body area between the rear ends of any two horizontal tunnels is the mining layer. After the mining layer is blasted, an in-situ crushed ore pile is formed. Between the middle sections of any two adjacent horizontal tunnels, an installation channel is drilled in the vertical direction. The installation channel includes an upper installation hole and a lower installation hole connected in sequence. The in-situ embedded leaching-adsorption circulation system for underground ore bodies includes an underground sealed pipeline moving bed, a leaching solution collection device, and a lean solution reuse device. The underground sealed pipeline moving bed includes a sealed storage tank, a central double pipe, and a lower liquid inlet tank connected sequentially from top to bottom. The sealed storage tank has an inner cavity A, and a lean liquid discharge pipe is sealed and installed on the side or top wall of the sealed storage tank. A resin drop outlet is located at the bottom of the sealed storage tank. The central double pipe includes an outer pipe and an inner pipe fixedly installed inside the outer pipe. A ring-shaped interlayer is formed between the inner and outer pipes, and the upper end of the ring-shaped interlayer connects to the resin drop outlet. The outer pipe includes a drop pipe, a conical pipe, and an impregnation material connected sequentially from top to bottom. The inner tube consists of a discharge pipe, a resin discharge port, and a screen pipe connected sequentially from top to bottom. The discharge pipe is installed in the inner hole of the discharge pipe. The lower inlet tank has an inner cavity B and a connecting port at the upper end, which is fixedly connected to the lower end of the impregnation pipe. The bottom of the lower inlet tank has a saturated resin outlet, and the side wall of the lower inlet tank has a rich liquid input pipe. The underground sealed pipeline moving bed is fixedly installed in the target installation channel and two horizontal tunnels connected at its upper and lower ends. The leachate collection device includes a extraction pipe, a leachate collection tank, and extraction pump A. The leachate collection tank is installed in the lower horizontal roadway, with a leachate inlet and a leachate outlet at its upper and lower ends, respectively. The front end of the extraction pipe extends into the in-situ crushed ore pile, the rear end of the extraction pipe is connected to the leachate inlet, and the leachate outlet is connected to the outer end of the rich solution input pipe. Two extraction pumps A are respectively located between the leachate collection tank and the rich solution input pipe, and between the leachate collection tank and the rear end of the extraction pipe. The lean liquor reuse device includes a leachate mixing tank, a spray pipe, an interlayer pipe, and a pump B. The leachate mixing tank is installed in the upper horizontal roadway, with a lean liquor recovery port and an acid addition port at its upper end. The lower end of the leachate mixing tank has a leachate outlet with a valve, and the lean liquor recovery port is connected to the outer port of the lean liquor discharge pipe. The spray pipe is located directly above the in-situ crushed ore pile, with an inlet and an outlet at each end, the outlet facing the in-situ crushed ore pile. The upper port of the interlayer pipe is connected to the leachate outlet, and the lower port of the interlayer pipe passes through the upper horizontal roadway, the vertical shaft, and the lower horizontal roadway in sequence, and is connected to the inlet. Two pumps B are respectively located between the leachate mixing tank and the lean liquor discharge pipe, and between the inlet of the spray pipe and the lower port of the interlayer pipe. The method is as follows: S01, Construct an in-situ crushed ore pile: A. A mine pit is excavated at the lower end of the mining layer; B. Create a false bottom at the bottom of the mine pit; C. Blasting the mining layer forms a ore pile; SO2, leaching and extraction of rich solutions: The leaching solution prepared in the leaching solution preparation tank is sprayed onto the in-situ crushed ore pile through the cross-layer pipe and spray pipe under the drive of the leaching pump B. The in-situ crushed ore pile leaches a rich solution containing uranyl complex. The rich solution is then pumped through the leaching pipe to the leaching solution collection tank under the drive of the leaching pump A, and then fed into the inner cavity B of the lower inlet tank through the rich solution input pipe. S03, the conversion between rich and poor solutions: After the rich solution enters the lower inlet tank, the following two events occur simultaneously: I. Unsaturated resin microspheres are dominated by the drag force of the rising liquid flow and are distributed in the upper part of the inner cavity B. Saturated resin microspheres are dominated by gravity and settle and accumulate at the bottom of the inner cavity B, eventually forming a "three-layer structure" in the inner cavity B. II. During the upward process, the rich solution comes into countercurrent contact with the unsaturated resin microspheres. The uranyl complex in the rich solution is adsorbed by the unsaturated resin microspheres, causing the rich solution to gradually become a lean solution. Under the combined action of the static pressure difference between the liquid level inside and outside the screen tube and the suction force of the pump B, the lean solution enters the screen tube and then passes through the delivery pipe, the connecting pipe and the lean solution discharge pipe in sequence, and enters the leachate preparation tank. S04, Regeneration and reuse of leachate: Acid is added to the leaching solution preparation tank through the acid addition port to regenerate the lean solution into leaching solution. The pump B is then started to discharge the leaching solution from the leaching solution outlet of the leaching solution preparation tank. The leaching solution is then sprayed onto the in-situ crushed ore pile through the interlayer pipe and spray pipe to achieve the regeneration and reuse of the leaching solution.

2. The in-situ sealed leaching-adsorption cycle process for underground ore bodies as described in claim 1, characterized in that: Step S01 is detailed below; A. Excavating a pit at the lower end of the mining layer: Define two adjacent horizontal roadways above and below the target mining layer as the upper horizontal roadway and the lower horizontal roadway, respectively. The target mining layer is located between the rear end of the upper horizontal roadway and the rear end of the lower horizontal roadway. In the lower horizontal roadway at the lower end of the target mining layer, excavate a pit of a certain depth as a reserved space for blasting compensation. B. Construct a false bottom at the bottom of the mine: Construct a false bottom at the bottom of the mine for load-bearing purposes, and lay a base with a water-proof effect on the upper surface of the false bottom. The false bottom is used to receive the crushed ore that will collapse during subsequent blasting of the target mining layer. C. Formation of ore pile by blasting mining layer: The target mining layer is blasted in situ, and the broken ore that falls from the blast naturally falls on the base above the false bottom, thus forming an in-situ broken ore pile.

3. The in-situ sealed leaching-adsorption cycle process for underground ore bodies as described in claim 2, characterized in that: In the underground sealed pipeline type moving bed, the outer pipe is vertically fixed in the target installation channel through a casting process. The upper end of the outer pipe extends into the horizontal tunnel connected to the upper end of the target installation channel, and the lower end of the outer pipe extends into the horizontal tunnel connected to the lower end of the target installation channel. The sealed storage tank is installed in the horizontal tunnel connected to the upper end of the target installation channel. The lower liquid inlet tank is installed in the horizontal tunnel connected to the lower end of the target installation channel.

4. The in-situ sealed leaching-adsorption cycle process for underground ore bodies as described in claim 3, characterized in that: The top of the sealed storage tank is equipped with an atmospheric vent, a compressed air injection port, and a sealed feeder; the atmospheric vent and the compressed air injection port are normally closed. In step S03, during the operation of the underground sealed pipeline moving bed, as more and more unsaturated resin microspheres are transformed into saturated resin microspheres, the saturated resin microspheres sink and accumulate at the bottom of the lower inlet tank cavity B. The gaps in the sealed storage tank cavity A and the annular interlayer also gradually increase, and the air pressure in the sealed storage tank cavity A and the annular interlayer gradually decreases, thereby causing the rich liquid level to rise continuously. In order to keep the rich liquid level within the range of "submerging the screen tube and not entering the annular interlayer", the atmospheric vent at the top of the sealed storage tank is opened periodically to allow a certain amount of outside air to enter the sealed storage tank cavity A and the annular interlayer. In step S03, during the operation of the underground sealed pipeline moving bed, if the resin microspheres in the annular interlayer become stuck together, compressed air is injected into the inner cavity A of the sealed storage tank and the annular interlayer through the compressed air injection port to push the stuck resin microspheres downward, so that the stuck resin microspheres enter the annular interval between the outer wall of the screen tube and the inner wall of the impregnation tube. In step S03, during the operation of the underground sealed pipeline moving bed, the valve on the saturated resin outlet at the bottom of the lower liquid inlet tank is opened to discharge the saturated resin microspheres accumulated at the bottom of the inner cavity B of the lower liquid inlet tank, thus obtaining the product of the closed-loop process.

5. The in-situ sealed leaching-adsorption cycle process for underground ore bodies as described in claim 4, characterized in that: The screen tube is 1-4m long, with an outer diameter of 75-85mm, and the immersion tube has an inner diameter of 390-410mm.

6. The in-situ sealed leaching-adsorption cycle process for underground ore bodies as described in claim 5, characterized in that: The discharge pipe is composed of multiple short discharge pipes with a length between 0.8 and 1.2 m connected by threads in sequence. The length of the discharge pipe exceeds the length of the upper mounting hole by 0.2-0.5 m. The liquid delivery pipe is composed of multiple short liquid delivery pipes with a length between 0.8 and 1.2 m connected by threads in sequence. The upper end of the uppermost short liquid delivery pipe exceeds the height of the upper end of the discharge pipe by 0.1-0.2 m.

7. The in-situ sealed leaching-adsorption cycle process for underground ore bodies as described in claim 6, characterized in that: The lower end of the immersion tube is provided with multiple axially extending strip grooves, and the upper end of each axially extending strip groove is connected to a circumferentially arranged arc groove; the inner hole of each short discharge tube is provided with multiple axially extending mounting grooves, and the direction of the axial mounting grooves is from the upper end of the short discharge tube to the lower end, but does not penetrate to the lower end of the short discharge tube. The inner tube is fixedly installed in the inner hole of the outer tube by a positioning assembly; the positioning assembly includes an end face support plate and multiple center positioning plates; the end face support plate is fixedly installed in the inner hole of the immersion tube, and the center positioning plates are installed in the inner hole of the discharge short tube; The end face support plate includes a center plate and multiple support plates A connected to the outside of the center plate. A fan-shaped perforation is formed between two adjacent support plates A to allow resin microspheres to pass through. The number of support plates A is consistent with the number of axial strip grooves and corresponds one-to-one. The number of support plates A is consistent with the number of circumferential arc grooves and corresponds one-to-one. The end face support plate slides into the inner hole of the impregnation tube from the lower end opening through the sliding fit between the support plates A and the axial strip grooves of the impregnation tube. When the end face support plate is pushed to the junction of the axial positioning groove and the circumferential arc groove of the impregnation tube, the end face support plate is rotated so that the support plates A on the end face support plate enter the corresponding circumferential arc groove in the inner hole of the impregnation tube, thus realizing the fixed installation of the end face support plate in the inner hole of the impregnation tube. The number of centering positioning plates corresponds one-to-one with the number of short discharge tubes in the discharge tube. The centering positioning plate includes an annular plate and multiple support plates B connected to the outside of the annular plate. A fan-shaped perforation is formed between two adjacent support plates B402 to allow resin microspheres to pass through. A through hole B is provided at the center of the annular plate for the liquid delivery short tube to slide through. A chamfer is provided at the upper end of the through hole B to guide the insertion of the pipe. The centering positioning plate is slidably pushed into the inner hole of the short discharge tube from the upper end of the discharge tube through the sliding fit between the support plate B and the axial mounting groove. The chamfer on the centering positioning plate faces the upper end of the discharge tube. When the centering positioning plate is pushed to the bottom of the axial mounting groove, the installation of the centering positioning plate in the inner hole of the short discharge tube is achieved.

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