Method for ion type rare earth ore bottom liquid collecting layer consolidation anti-permeation and rare earth mother liquor recovery

Abstract

The present application relates to a method for ion type rare earth ore bottom liquid collecting layer consolidation impermeable and rare earth mother liquor recovery, belongs to ion type rare earth ore in-situ leaching technical field.The method forms a liquid collecting layer by consolidating the ore body bottom soil, and realizes the efficient recovery of rare earth mother liquor by using the formed impermeable liquid collecting layer and the guide casing arranged in the shape of plum blossom array.The control platform injects the solution into the ore body bottom soil according to the injection sequence of "water-bacteria solution-water-cementing solution-water" and the set injection time.The calcium carbonate precipitated by the microorganism induction effectively fills the soil pores, so that the ore body bottom forms a liquid collecting layer with impermeable characteristics.In the in-situ leaching process, the rare earth mother liquor seeped down is effectively intercepted by the impermeable liquid collecting layer, and flows along the surface of the liquid collecting layer to the guide casing, and then the mother liquor is introduced to the mountain ring collecting ditch through the plum blossom type liquid collecting port of the guide casing and the geotextile mesh hole, which improves the recovery efficiency of the mother liquor, and helps to reduce resource loss and environmental pollution.

Description

Technical Field

[0001] This invention relates to the field of in-situ leaching technology for ion-adsorption rare earth minerals, and in particular to a method for consolidating and preventing seepage in the bottom liquid collection layer of ion-adsorption rare earth minerals and for recovering rare earth mother liquor. Background Technology

[0002] Rare earth elements, as indispensable raw materials for high-tech industries, are widely used in defense, military, and new energy fields. In weathered crust leaching of rare earth ores, rare earth elements are mainly adsorbed on the surface of clay minerals in the form of hydrated or hydroxyl hydrated cations, which allows rare earth ions to dissociate through chemical and biological processes. Currently, the main mining method for ion-adsorption rare earth ores is in-situ leaching. During the mining process, due to the presence of a completely weathered layer or bedrock buried deep underground at the bottom of the mine, some rare earth mother liquor and leaching solution leak into the soil and groundwater around the mining area, causing serious loss of rare earth resources and environmental pollution.

[0003] To address the issues of rare earth mother liquor leakage and environmental pollution during in-situ leaching of ion-adsorption rare earth ores, common methods for recovering the rare earth mother liquor currently proposed mainly include excavating collection tunnels and chambers at the foot of the ion-adsorption rare earth mine, and installing interception devices for in-situ leaching of ion-adsorption rare earth ores. The collection tunnel and chamber recovery method primarily involves excavating a collection tunnel at the foot of the mine, excavating a chamber at the end of the collection tunnel, installing flow guiding elements around the chamber, and simultaneously treating the collection tunnel and chamber with concrete for seepage prevention. The interception and collection device for in-situ leaching of ion-adsorption rare earth ores is a multi-layered interception and collection network composed of V-shaped flow guiding channels, designed to effectively intercept and collect the rare earth mother liquor.

[0004] Currently, MICP technology has achieved certain results in slope reinforcement, concrete repair, and windbreak and sand fixation. However, research on its application to the consolidation and seepage prevention of the bottom liquid-collecting layer in ion-adsorption rare earth mines, as well as the recovery of rare earth mother liquor during in-situ leaching, has not yet been conducted. When using manual injection to consolidate the bottom liquid-collecting layer of ion-adsorption rare earth mines, the phenomenon of "blind injection" easily occurs. Traditional injection processes use constant pressure injection, which can easily cause local erosion of the liquid-collecting layer during consolidation, affecting the seepage prevention effect and mother liquor recovery efficiency. Therefore, there is an urgent need to develop a new method for consolidating and preventing seepage in the bottom liquid-collecting layer of ion-adsorption rare earth mines and recovering rare earth mother liquor, achieving efficient recovery of rare earth mother liquor. Simultaneously, an automated injection platform should be introduced to manage the injection process, dynamically adjusting the injection rate and pressure by receiving and analyzing sensor feedback data, thereby reducing manpower and material consumption. Summary of the Invention

[0005] To address the resource loss, environmental pollution, and localized erosion of the liquid-collecting layer during in-situ leaching mining of ion-adsorption rare earth deposits, this invention provides a method for consolidating and preventing seepage in the bottom liquid-collecting layer of ion-adsorption rare earth deposits and recovering rare earth mother liquor. This method utilizes MICP technology and automated injection technology to consolidate the liquid-collecting layer. In each injection cycle, the control platform injects the solution into the soil at the bottom of the ion-adsorption rare earth deposit according to the injection sequence of "clean water-bacterial solution-clean water-cementing solution-clean water" and the set injection time. The injection rate and pressure are dynamically adjusted based on data from the water pressure sensor on the injection pipe to achieve precise injection. During the consolidation process, after the bacterial solution comes into contact with the cementing solution, the calcium carbonate precipitate induced by microorganisms fills the gaps between soil particles, thereby reducing the soil's permeability coefficient and enhancing the cohesion between particles. After the liquid-collecting layer is consolidated, guide holes are arranged at equal intervals on the upper surface of the liquid-collecting layer, and guide sleeves are arranged in a quincunx pattern within the guide holes. In the subsequent in-situ leaching process, the seepage-proof properties of the solidified liquid-collecting layer are utilized to effectively intercept the seeping rare earth mother liquor. Then, a plum blossom-shaped array of guide sleeves is used to systematically guide the mother liquor to the surrounding collection ditch, achieving efficient recovery of the rare earth mother liquor. This method effectively inhibits the leakage of rare earth mother liquor into the surrounding mining area. Furthermore, the introduction of a control platform to regulate the injection process avoids "blind injection" and localized erosion of the liquid-collecting layer. The design of the guide sleeves also effectively prevents the collapse of the guide holes and pipe blockage. The technical solution is as follows:

[0006] A method for consolidating and preventing seepage in the bottom liquid-collecting layer of ion-adsorption rare earth mines and recovering rare earth mother liquor involves using MICP technology and a set injection process to inject bacterial solution and cementing solution to consolidate the soil and form a liquid-collecting layer. The seepage-proof properties of the liquid-collecting layer can prevent the rare earth mother liquor from seeping downwards. Then, the rare earth mother liquor is recovered to the Huanshan liquid collection ditch using the guide sleeve in the guide hole.

[0007] The method for consolidating and preventing seepage at the bottom of the liquid-collecting layer of ion-adsorption rare earth ore and for recovering rare earth mother liquor includes the following steps:

[0008] S1. Based on the geological conditions and shape of the ore body in the mining area, injection holes are arranged on the slope or foot of the mountain parallel to the bottom of the ore body, and all injection holes are arranged in a straight line; bacterial solution pools, cementing solution pools and clear water pools are arranged at the foot of the mountain; the solutions in the bacterial solution pools, cementing solution pools and clear water pools are transported to the injection pipes through the delivery pipes, and the injection pipes extend into the injection holes.

[0009] S2. Following the injection sequence of clean water-bacterial solution-clean water-cementing solution-clean water and the set injection time, inject the corresponding solution into the soil at the bottom of the ore body through the injection pipe. Repeat the above injection cycle 3 to 6 times until the liquid collection layer is consolidated.

[0010] S3. After the liquid collection layer is solidified, guide holes are arranged at equal intervals on the upper surface of the liquid collection layer, and guide sleeves are laid in the guide holes.

[0011] S4. During the in-situ leaching process, the rare earth mother liquor is recovered to the Huanshan collection ditch through the guide sleeve arranged in the guide hole.

[0012] The injection holes are arranged at an upward inclination of 3 to 8 degrees along the horizontal plane. The diameter of the injection holes is 8 to 12 cm. All injection holes are arranged in a straight line. The horizontal distance between the openings of two adjacent injection holes is equal, and the interval between the openings of two adjacent injection holes is 1 to 1.5 m.

[0013] The injection pipe has a diameter of 8–12 cm, and its length is similar to the depth of the injection hole. The upper part of the injection pipe is a closed structure, and the lower part of the injection pipe inside the injection hole has an outlet. The outlet area occupies 20–30% of the total injection pipe area, with 4–8 outlets arranged in the same row to facilitate downward seepage of the solution. The diameter of the outlet is 1 cm, and the distance between outlets in adjacent rows is 3–5 cm. All injection pipes are connected in parallel, and each injection pipe is equipped with a smart flow meter, a smart pressure booster, a smart on / off valve, and at least two water pressure sensors.

[0014] The infusion tube is equipped with three input ports and multiple output ports. The three input ends of the infusion tube extend into the bacterial solution tank, the cementing solution tank, and the clear water tank, respectively. Each of the three input ends of the infusion tube is equipped with an intelligent infusion valve and an intelligent flow meter. The output ports are connected to the input ports of all the injection tubes.

[0015] The specific injection sequence and injection time in step S2 are as follows:

[0016] Clean water from the clean water tank is injected into the soil through infusion and injection pipes. After 1-3 hours of water injection, bacterial solution from the bacterial solution tank is injected into the soil through the infusion and injection pipes after a 24-hour interval. After 24-32 hours of bacterial solution injection, the injection is stopped. After a 3-6 hour interval, clean water is injected for 1-3 hours to clean the pipes. Finally, cementing solution from the cementing solution tank is injected into the soil through the infusion and injection pipes. After 24-32 hours of cementing solution injection, the injection is stopped. After a 64-72 hour interval, clean water is injected for 1-3 hours to clean the pipes, completing one injection cycle.

[0017] During the injection process, the water pressure sensor detects the pressure near the injection pipe and transmits it to the control platform. The control platform compares the feedback data with the pressure data from the previous cycle. If an increase in pressure is detected, the injection rate and injection pressure are reduced in the next cycle. The multiple of pressure increase near the injection pipe is proportional to the multiple of reduction in injection rate and injection pressure.

[0018] The liquid-collecting layer is formed by the soil at the bottom of the calcium carbonate precipitated and consolidated ore body. The liquid-collecting layer is a continuous guiding plane with an inclination angle of 3 to 8°, which has a good seepage prevention effect and can effectively intercept rare earth mother liquor.

[0019] The length of the guide sleeve is equal to the depth of the guide hole, and the pipe diameter is 10cm. It adopts a double-layer filter structure, with an external PVC screen pipe, an opening rate of 25%±2%, a hole diameter of 5mm, and arranged in a plum blossom pattern. It has an internal geotextile lining, which can orderly guide the rare earth mother liquor to the Huanshan collection ditch.

[0020] The bacterial solution is a Bacillus pasteurellii bacterial solution with an OD600 of 0.6–1.5; the cementing solution is a mixed solution of calcium chloride and urea with equimolar concentrations and a cementing solution concentration of 1–2 mol / L.

[0021] Typically, at the foot of the mountain, cylindrical solution pools are set up, including 2 to 3 bacterial solution pools and cementing solution pools, one clear water pool, and another solution pool as a backup pool. Each solution pool is 6m deep and 8m in diameter.

[0022] During the consolidation process, all intelligent flow meters, intelligent pressure boosters, intelligent on / off valves, water pressure sensors, and intelligent infusion valves are connected to the control platform via wired or wireless means. The control platform controls the valve opening according to the pre-set injection procedure, while simultaneously receiving data from monitoring devices and displaying in real-time the flow rate, velocity, and water pressure near the injection pipe for all pipelines. Water pressure sensors monitor pressure data near the injection pipe and send it to the control platform. Intelligent on / off valves control the flow rate of the solution in the injection pipe, intelligent flow meters control the flow rate of the solution in the injection pipe and display the flow rate and total flow rate in real-time, intelligent pressure boosters adjust the injection pressure, and intelligent infusion valves control the corresponding solution to enter the infusion pipe according to the injection requirements.

[0023] Both intelligent switching valves and intelligent infusion valves include a valve body, valve core, drive device, control panel, and signal transceiver module. The signal transceiver module is connected and interconnected with the control panel. The control panel, upon receiving instructions, controls the drive device to operate, and the drive device drives the valve core to work. The signal transceiver module is either a Bluetooth module or a WIFI module.

[0024] Both the intelligent pressurizer and the intelligent flow meter include a sensor, a control panel, a drive unit, and a signal transceiver module. The intelligent pressurizer also includes a pressure machine, and the intelligent flow meter also includes a counter and a flow switch. The control platform controls the drive unit, which drives the pressure machine and the flow switch. The flow switch controls the flow rate of the solution in the injection tube.

[0025] The control platform receives data and sends commands through a data transceiver device, which includes a GPRS communication module and a 5G communication module.

[0026] The beneficial effects of the technical solutions provided in the embodiments of the present invention include at least the following:

[0027] This solution combines MIP (Micro-Injection Polymerization) technology and automated injection technology to consolidate the soil at the bottom of the ore body, forming a liquid-collecting layer. The resulting impermeable liquid-collecting layer and guide sleeves then enable efficient recovery of rare earth mother liquor. During injection, the control platform issues commands according to a preset injection procedure, sequentially injecting bacterial solution, clean water, and cementing fluid into the soil at the bottom of the ore body. The consolidation effect of the planar liquid-collecting layer is monitored throughout the process. By receiving and analyzing data from sensors, the injection rate and pressure are dynamically adjusted, reducing manpower and material consumption. After the liquid-collecting layer is consolidated, all equipment and pipelines can be reused, effectively reducing overall mining costs. Furthermore, the use of microorganisms derived from the natural environment for liquid-collecting layer consolidation and seepage prevention results in reaction products that are environmentally friendly, meeting green mining requirements. The microbially induced calcium carbonate precipitation can be used to reinforce the mountain or decompose directly after mining, without the risk of secondary pollution. During the in-situ leaching stage, the rare earth mother liquor seeps downward and is intercepted by the liquid collection layer with anti-seepage properties. It then collects along the guide holes on the surface of the liquid collection layer and is finally recycled into the Huanshan collection ditch in an orderly manner using the guide sleeves arranged in a plum blossom pattern.

[0028] Clearly, the above method effectively prevents leaching solution leakage and achieves efficient recovery of rare earth mother liquor, fundamentally solving problems such as low rare earth mother liquor recovery rate, environmental pollution, and localized erosion of the liquid collection layer. Furthermore, the invention's use of a control platform to regulate the injection process not only saves significant manpower and costs but also simplifies operation steps and allows for real-time monitoring of the consolidation effect of the liquid collection layer during injection, achieving precise injection. The guide sleeve used in this method prevents the guide hole from collapsing, and its outer quincunx array structure prevents soil particles from entering the sleeve, thus avoiding blockage problems caused by particle aggregation. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 This is a schematic cross-sectional view of the injection process of the bottom liquid collection layer of a consolidated ion-type rare earth ore according to an embodiment of the present invention.

[0031] Figure 2 This is a schematic diagram of the arrangement of injection holes in the bottom liquid collection layer of a consolidated ion-type rare earth ore according to an embodiment of the present invention;

[0032] Figure 3 This is a schematic diagram of the injection tube structure extending into the injection hole in an embodiment of the present invention;

[0033] Figure 4This is a schematic diagram of the intelligent device structure involved in the injection process of the bottom liquid collection layer of a consolidated ion-type rare earth ore, provided in an embodiment of the present invention.

[0034] Figure 5 This is a flowchart of a bottom liquid collection layer of a consolidated ion-type rare earth ore provided in an embodiment of the present invention;

[0035] Figure 6 This is a schematic diagram of the in-situ leaching and liquid collection process of the solidified liquid collection layer in an embodiment of the present invention;

[0036] Figure 7 This is a schematic diagram of the flow guide sleeve in an embodiment of the present invention.

[0037] The components are: 1-Intelligent infusion valve; 2-Control platform; 3-Injection pipe; 4-Mineral soil layer; 5-Fully weathered layer; 6-Intelligent pressure booster; 7-Intelligent flow meter; 8-Intelligent on / off valve; 9-Infusion pipe; 10-Injection hole; 11-Outlet; 12-Water pressure sensor; 13-Geotextile lining; 14-Intelligent equipment; 15-Control panel; 16-Drive device; 17-Working module; 18-Signal transceiver module; 19-Bacterial solution; 20-Cementing solution; 21-Drainage hole; 22-Planar liquid collection layer; 23-Unconsolidated soil layer; 24-Drainage sleeve; 25-Liquid collection ditch; 26-Plum blossom-shaped liquid collection port. Detailed Implementation

[0038] The technical solution of the present invention will now be described with reference to the accompanying drawings.

[0039] In embodiments of the present invention, words such as "exemplarily," "for example," etc., are used to indicate that something is an example, illustration, or description. Any embodiment or design described as "exemplary" in the present invention should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of the word "exemplary" is intended to present the concept in a concrete manner. Furthermore, in embodiments of the present invention, the meaning expressed by "and / or" can be both, or either one.

[0040] In this embodiment of the invention, sometimes a subscript such as W1 may be written in a non-subscript form such as W1. When the difference is not emphasized, the meaning they express is the same.

[0041] To make the technical problems, technical solutions and advantages of the present invention clearer, a detailed description will be given below in conjunction with the accompanying drawings and specific embodiments.

[0042] Existing bottom liquid collection methods typically involve interfering with the original soil structure to recover rare earth mother liquor. However, this invention optimizes the internal structure of the soil and innovatively improves the liquid injection method based on manual injection. It is the first to combine automated liquid injection technology with MICP technology to consolidate the liquid collection layer at the bottom of ion-adsorption rare earth ore. It is also the first to propose that the liquid collection layer structure be a continuous flow-guiding plane, and the first to propose the use of a plum blossom-shaped array of flow-guiding sleeves to recover rare earth mother liquor.

[0043] A row of injection holes is excavated at the bottom of the ore body or at the foot of the mountain. Automated injection technology is used to sequentially inject bacterial solution, clean water, and cementing solution into the soil at the bottom of the ore body. Microbially induced calcium carbonate precipitates fill the gaps between soil particles, and the calcium carbonate combines with the soil to form a liquid-absorbing layer. The injection process mainly utilizes a control platform, intelligent flow meters, intelligent pressure boosters, intelligent on / off valves, intelligent delivery valves, and water pressure sensors. The control platform is responsible for sending instructions to the intelligent flow meters, intelligent pressure boosters, intelligent on / off valves, and intelligent delivery valves, and receiving and processing data from the intelligent flow meters and water pressure sensors. It then sends instructions to adjust the injection rate and pressure, and displays the total flow rate, flow velocity, and water pressure near the injection pipe in real time. After the bacterial solution is injected into the soil, the solution seeps downwards and diffuses. When the bacterial solutions from both sides of the injection hole converge, clean water and cementing solution are injected sequentially. After the cementing solution comes into contact with the bacterial solution, the microorganisms adsorb the calcium carbonate in the cementing solution. 2+ Ca 2+ With CO3 2- The process involves the formation of calcium carbonate precipitate, which adheres to and grows on the surface of soil particles, bridging adjacent particles and forming a liquid-collecting layer with impermeable properties. After the liquid-collecting layer has solidified, diversion holes are arranged at equal intervals on its upper surface, and diversion sleeves are arranged in a quincunx pattern within these holes. The planar liquid-collecting layer solidified using the method described in this invention effectively intercepts rare earth mother liquor, causing it to collect along the surface of the liquid-collecting layer. The quincunx-patterned diversion sleeves then collect the rare earth mother liquor back into the surrounding drainage ditch, preventing further downward seepage.

[0044] This invention provides a method for consolidating and preventing seepage in the bottom liquid collection layer of ion-type rare earth mines and for recovering rare earth mother liquor.

[0045] like Figure 6 A method for consolidating and preventing seepage in the bottom liquid collection layer of ion-type rare earth mines and recovering rare earth mother liquor involves using MICP technology and a set injection process to inject bacterial solution and cementing solution to consolidate the soil and form a liquid collection layer. The seepage prevention properties of the liquid collection layer can prevent the rare earth mother liquor from seeping downwards. Then, the rare earth mother liquor is recovered to the Huanshan liquid collection ditch using the guide sleeve in the guide hole.

[0046] Specific methods for consolidating and preventing seepage in the liquid-collecting layer, such as Figure 1 , Figure 2As shown, the specific method for recovering rare earth mother liquor includes the following steps:

[0047] S1. Based on the geological conditions and ore body shape of the mining area, injection holes 10 are arranged on the slope or foot of the mountain parallel to the bottom of the ore body soil layer 4. The lower part of the injection holes 10 is the completely weathered layer 5, and all injection holes are arranged in a straight line. At the foot of the mountain, bacterial liquid pool, cementing liquid pool and clear water pool are arranged. The bacterial liquid pool, cementing liquid pool and clear water pool are connected to the injection pipe 3 through the infusion pipe 9. The injection pipe 3 extends into the injection hole 10. The infusion pipe 9 is equipped with an intelligent infusion valve 1, an intelligent switch valve 8 and an intelligent flow meter 7. An intelligent pressure booster 6 is provided at the junction of the infusion pipe 9 and the injection pipe 3. A water pressure sensor 12 is provided on the outside of the injection pipe 3. The intelligent infusion valve 1, intelligent pressure booster 6, intelligent flow meter 7, intelligent switch valve 8 and water pressure sensor 12 are all connected to the control platform 2 through wired or wireless means.

[0048] S2. Following the injection sequence of clean water-bacterial solution-clean water-cementing solution-clean water and the set injection time, inject the corresponding solution into the soil at the bottom of the ore body through the outlet 11 of the injection pipe 3. Repeat the above injection cycle 3 to 6 times until the liquid collection layer is consolidated.

[0049] S3. After the liquid collection layer is solidified, guide holes 21 are arranged at equal intervals on the upper surface of the planar liquid collection layer 22, and guide sleeves 24 are laid in the guide holes 21.

[0050] S4. During the in-situ leaching process, the rare earth mother liquor is intercepted by the liquid collection layer with anti-seepage properties, and then the rare earth mother liquor is recovered to the Huanshan collection ditch 25 by the guide sleeve arranged in the guide hole.

[0051] The following description, in conjunction with specific embodiments, illustrates this point.

[0052] In the embodiments of this invention, the tryptone, soybean peptone, NaCl, urea and related materials in the culture medium are all conventional commercially available products; the microorganism used is Bacillus pasteurellii, which was purchased from the Beijing Center for Biological Culture Collection; the injection tubes, infusion tubes, water pressure sensors and other equipment used are all conventional commercially available products.

[0053] The CASO liquid culture medium used to prepare the growth medium for Bacillus pasteurellis consists of: 15 g / L tryptone, 5 g / L soybean peptone, 5 g / L sodium chloride, 20 g / L urea, and deionized water.

[0054] According to Figure 1 The diagram shows the arrangement of a solution tank, delivery pipes, injection pipes, intelligent flow meters, and other equipment. Injection holes are excavated at the bottom of the ore body or at the foot of the mountain. All injection holes are arranged in a straight line and are inclined upwards at 4° along the horizontal plane. Figure 2As shown, the diameter of injection hole 10 is 12cm, and the horizontal distance between the openings of two adjacent injection holes is equal, with an interval of 1.2m. The depth of the injection holes is adjusted according to the distribution characteristics of the mountain and ore body. Based on the distribution of injection holes, a bacterial solution pool, a cementing solution pool, and a clear water pool are excavated at the foot of the mountain, maintaining a distance of 20 to 100m between the solution pools and the injection hole openings. An injection pipe 3 is installed in injection hole 10, with a length similar to the depth of the injection hole. The input port of injection pipe 3 is connected to the output port of delivery pipe 9. The delivery pipe has three input ports and multiple output ports. The three input ends of the delivery pipe extend into the bacterial solution pool, the cementing solution pool, and the clear water pool, respectively. Each of the three input ends of the delivery pipe is equipped with an intelligent delivery valve and an intelligent flow meter. After the injection pipe is arranged, the openings of the injection holes are sealed to provide a sealed environment for subsequent pressurized injection.

[0055] like Figure 3 The upper part of the injection pipe 3 adopts a closed structure, and the lower part of the injection pipe 3 inside the injection hole 10 has an outlet 11. The outlet area occupies 20% of the entire injection pipe, and five outlets 11 are arranged in the same row to facilitate downward seepage of the solution. The diameter of the outlet is 1 cm, and the distance between outlets in adjacent rows is 4 cm. All injection pipes are distributed in parallel, and each injection pipe is equipped with a smart flow meter, a smart pressure booster, a smart switching valve, and no less than two water pressure sensors.

[0056] After the injection system is set up, the injection operation begins. The control platform opens the intelligent infusion valve in the clear water tank and all intelligent on / off valves and intelligent pressure boosters on the injection pipes, injecting clear water under pressure for 2 hours. Then, the intelligent infusion valve in the clear water tank is closed, and the initial water pressure sensor data is collected and transmitted to the control platform. After 24 hours, the intelligent infusion valve in the bacterial solution tank is opened, injecting bacterial solution under pressure for 32 hours. Then, the intelligent infusion valve in the bacterial solution tank is closed. After injecting the bacterial solution, after an interval of 5 hours, the intelligent infusion valve in the clear water tank is opened, injecting clear water under pressure for 1 hour to clean the pipeline, then the intelligent infusion valve in the clear water tank is closed. The intelligent infusion valve in the cementing solution tank is opened, injecting cementing solution for 32 hours. Finally, all intelligent infusion valves, intelligent on / off valves, and intelligent pressure boosters are closed. After an interval of 72 hours, the intelligent infusion valve in the clear water tank and all intelligent on / off valves and intelligent pressure boosters are opened again, injecting clear water for 2 hours to clean the pipeline. During the injection process, the water pressure sensor monitors the pressure near the injection pipe and transmits it to the control platform. The control platform compares the feedback data with the pressure data from the previous cycle. If an increase in pressure is detected, the injection rate and injection pressure are reduced in the next cycle. The factor by which the pressure near the injection pipe increases is proportional to the factor by which the injection rate and injection pressure are reduced. This injection process is repeated for six injection cycles until the liquid layer has solidified.

[0057] like Figure 5As shown, during the injection of bacterial solution, Bacillus pasteurellii is evenly distributed in the soil and adsorbed onto the surface of soil particles. The urease produced decomposes urea to generate CO3. 2- The purpose of pressurizing and injecting clean water is to remove microorganisms accumulated near the outlet, preventing the cementing solution from coming into contact with microorganisms and rapidly generating large amounts of calcium carbonate precipitates that clog the pores, while also cleaning the pipes. Subsequently, the cementing solution is pressurized and injected; the calcium in the cementing solution... 2+ With CO3 2- The bacterial solution 19 combines to form calcium carbonate precipitate. After being injected into the soil, the bacterial solution seeps downwards and spreads outwards. After 32 hours of injection, the bacterial solutions injected from two adjacent injection holes meet. Following this, water is injected to further expand the seepage range of the bacterial solution. Then, cementing solution 20 is injected. During the seepage of the cementing solution, the calcium carbonate precipitate induced by Bacillus pasteurellii continuously increases. With multiple cycles of solution injection, calcium carbonate continues to grow in the pores, filling the pores of soil particles, ultimately forming a liquid-absorbing layer with impermeable properties.

[0058] After the planar liquid collection layer has solidified, all intelligent infusion valves, intelligent switching valves, and intelligent pressurizers are shut off, and the infusion tubing and injection tubing are cleaned. Subsequently, guide holes 21 are arranged at equal intervals on the upper surface of the liquid collection layer, and guide sleeves arranged in a quincunx pattern are laid in the guide holes 21.

[0059] like Figure 6 As shown, the planar liquid-collecting layer 22 plays a major role in the in-situ leaching process. The planar liquid-collecting layer intercepts the seeping rare earth mother liquor, which collects on the upper surface of the liquid-collecting layer, preventing it from entering the unconsolidated soil layer 23. Then, the rare earth mother liquor is recovered into the guide sleeve 24 through the quincunx-shaped liquid-collecting ports 26 on the guide sleeve and the mesh of the geotextile lining 13. Finally, it is led through the guide sleeve to the ring-shaped liquid collection ditch 25, and ultimately recovered into the collection tank. This method, applied to the in-situ leaching process of ion-adsorption rare earth ores, not only achieves efficient recovery of rare earth resources and prevents pollution of the surrounding environment from the source by the leakage of leaching solution, but also reduces manpower and material consumption and simplifies the operation steps.

[0060] In this embodiment, guide holes are arranged at equal intervals on the upper surface of the liquid collecting layer. The guide holes are arranged at a 4° upward angle along the horizontal plane, parallel to the surface of the liquid collecting layer, and the distance between the openings of two adjacent guide holes is 1.2m. A guide sleeve is laid in the guide hole 21 to prevent the guide hole from collapsing. The guide sleeve 24 is as follows: Figure 7 As shown, the length of the guide sleeve is equal to the depth of the guide hole, and the pipe diameter is 10cm. It adopts a double-layer filter structure, with an external PVC screen pipe, an opening rate of 25%, and a hole diameter of 5mm, arranged in a plum blossom pattern. It has an internal geotextile lining layer 13 to prevent soil particles from entering the guide sleeve and causing pipe blockage.

[0061] The concentration of the bacterial solution used in the above injection process is OD.600 =0.7, the cementing solution is a mixture of calcium chloride and urea with equimolar concentrations, wherein the concentrations of calcium chloride and urea are both 1.5 mol / L. Only one bacterial solution and one cementing solution are injected in one cycle, and the entire injection process includes 6 injection cycles.

[0062] like Figure 4 As shown, the intelligent device 14 of the present invention includes a control panel 15, a drive device 16, a working module 17, and a signal transceiver module 18. Both the intelligent switching valve and the intelligent infusion valve include a valve body, a valve core, a drive device, a control panel, and a signal transceiver module. The signal transceiver module is connected and interconnected with the control panel. The control panel, upon receiving instructions, controls the operation of the drive device, which in turn drives the valve core to work. The signal transceiver module is either a Bluetooth module or a WIFI module.

[0063] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A method for ion-type rare earth ore bottom liquid collection layer consolidation impermeable and rare earth mother liquor recovery, characterized in that, The steps include the following: S1, according to the geological conditions and the shape of the ore body, arranging the injection holes in the slope or the foot of the mountain parallel to the bottom of the ore body, all the injection holes are arranged in a straight line; arranging the bacterial liquid pool, the cementing liquid pool and the water pool at the foot of the mountain; the solutions in the bacterial liquid pool, the cementing liquid pool and the water pool are transported to the injection pipes through the infusion pipes, and the injection pipes are inserted into the injection holes; S2, according to the injection sequence of water-bacterial liquid-water-cementing liquid-water and the set injection time, the corresponding solution is injected into the soil at the bottom of the ore body through the injection pipe, and the above injection cycle is repeated for 3-6 times until the consolidation of the leaching layer is completed; S3, after the consolidation of the leaching layer is completed, arranging the drainage holes at equal intervals on the upper surface of the leaching layer, and laying the drainage sleeve pipes in the drainage holes; S4, during the in-situ leaching process, the rare earth mother liquor is recovered to the ring mountain collection ditch through the drainage sleeve pipes arranged in the drainage holes.

2. The method for ion-type rare earth ore bottom liquid collecting layer consolidation impermeable and rare earth mother liquor recovery according to claim 1, characterized in that, The injection holes are arranged upwardly inclined along the horizontal plane at an angle of 3-8°, the diameter of the injection holes is 8-12 cm, all the injection holes are arranged in a straight line, the horizontal distance between the orifices of the two adjacent injection holes is equal, and the interval distance between the orifices of the two adjacent injection holes is 1-1.5 m.

3. The method for ion-type rare earth ore bottom liquid collecting layer consolidation impermeable and rare earth mother liquor recovery according to claim 1, characterized in that, The diameter of the injection pipe is 8-12 cm, the length of the injection pipe is close to the depth of the injection hole; the upper half of the injection pipe adopts airtight structure, the lower half of the injection pipe in the injection hole is provided with a liquid outlet, the area of the liquid outlet accounts for 20-30% of the area of the whole injection pipe, 4-8 liquid outlets are arranged in the same column for facilitating the downward seepage of the solution, the diameter of the liquid outlet is 1 cm, and the distance between the two adjacent columns of liquid outlets is 3-5 cm.

4. The method for ion-type rare earth ore bottom liquid collecting layer consolidation impermeable and rare earth mother liquor recovery according to claim 3, characterized in that, The injection pipes are distributed in parallel, and the injection pipes are all equipped with intelligent flow meters, intelligent pressure boosters, intelligent on-off valves and not less than two water pressure sensors.

5. The method for ion-type rare earth ore bottom liquid collecting layer consolidation impermeable and rare earth mother liquor recovery according to claim 1, characterized in that, The infusion pipe is provided with three input ports and multiple output ports, the three inputs of the infusion pipe are inserted into the bacterial liquid pool, the cementing liquid pool and the water pool, and the three inputs of the infusion pipe are all equipped with intelligent infusion valves and intelligent flow meters; the output ports are connected with the input ports of all the injection pipes.

6. The method for ion-type rare earth ore bottom liquid collecting layer consolidation impermeable and rare earth mother liquor recovery according to claim 1, characterized in that, The injection sequence and injection time in step S2 are as follows: The water in the water pool is injected into the soil through the infusion pipe and the injection pipe, after 1-3 hours of water injection, the bacterial liquid in the bacterial liquid pool is injected into the soil through the infusion pipe and the injection pipe after an interval of 24 hours, the injection of the bacterial liquid is continued for 24-32 hours, then the injection is stopped, 1-3 hours of water is continuously injected for cleaning the pipeline after an interval of 3-6 hours; finally, the cementing liquid in the cementing liquid pool is injected into the soil through the infusion pipe and the injection pipe, the injection of the cementing liquid is continued for 24-32 hours, then the injection is stopped, 1-3 hours of water is injected again for cleaning the pipeline after an interval of 64-72 hours, and one injection cycle is completed.

7. The method for ion-type rare earth ore bottom liquid collecting layer consolidation impermeable and rare earth mother liquor recovery according to claim 4, characterized in that, During the injection process, the water pressure sensor detects the pressure near the injection pipe and transmits it to the control platform, the control platform compares the feedback data with the pressure data of the last cycle, if the pressure is detected to be enhanced, the injection rate and the injection pressure of the next cycle are reduced, and the enhancement multiple of the pressure near the injection pipe is proportional to the reduction multiple of the injection rate and the injection pressure.

8. The method for ion-type rare earth ore bottom liquid collecting layer consolidation impermeable and rare earth mother liquor recovery according to claim 1, characterized in that, The liquid collecting layer is formed by calcium carbonate precipitation consolidation of the bottom soil of the ore body, and is a continuous flow guide plane with an inclination angle of 3-8°, which has good anti-seepage effect and can effectively intercept the rare earth mother liquor.

9. The method for ion-type rare earth ore bottom liquid collecting layer consolidation impermeable and rare earth mother liquor recovery according to claim 1, characterized in that, The flow guide sleeve adopts a double-layer filtering structure, an external PVC screen pipe, a length of the flow guide sleeve equal to the depth of the flow guide hole, a pipe diameter of 10 cm, an opening rate of 25%±2%, a hole diameter of 5 mm, and a plum blossom array arrangement of the internal geotextile lining.

10. The method for ion-type rare earth ore bottom liquid collecting layer consolidation impermeable and rare earth mother liquor recovery according to claim 1, characterized in that, The bacteria liquid is a bacillus pasteurii bacteria liquid, the bacteria liquid concentration is OD 600 =0.6~1.5;The cementing liquid is a mixed solution prepared by equimolar concentration of calcium chloride and urea, the cementing liquid concentration is 1~2mol / L.

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