Pressure-resistant protection device and method for fluid filter element in in-situ leaching uranium process

Abstract

The present invention discloses a pressure-resistant protection device and method for a fluid filter element in an in-situ leaching uranium process, relating to the technical field of in-situ leaching uranium. The device has a reasonable structural design. By arranging a first damping structure on a first branch, the high-pressure fluid can be initially depressurized. By arranging a second branch, the fluid in the first branch can be diverted, so that a part of the fluid after the initial depressurization directly enters the annular cavity from the first liquid inlet and is filtered through a cylindrical filter element, and the other part enters the interior of the cylindrical filter element from the second liquid inlet after secondary depressurization by the second damping structure. The pressure-reducing effect of the first damping structure and the diverting effect of the second branch on the fluid initially reduce the impact strength of the fluid on the filter element. The mutual offsetting effect of the fluid pressures inside and outside the filter element further reduces the pressure difference on both sides of the filter element, which can significantly reduce the impact force of the fluid on the filter element, thereby achieving the purposes of protecting the filter element structure, extending the service life of the filter element, reducing costs and increasing efficiency, and the operating process is simple.

Description

Technical Field

[0001] The present invention relates to the technical field of in-situ leaching uranium, and in particular to a pressure-resistant protection device and method for a fluid filter element in an in-situ leaching uranium process. Background Art

[0002] The in-situ uranium leaching process extracts the leachate from the ground through continuous pumping and injection, and then injects the leachate back into the ground after the metal is extracted. However, the process fluid usually contains colloidal impurities and other solid fine particles. To prevent impurities and particles from entering the process equipment and being injected into the underground ore layer, affecting normal operation, a two-stage fine filtration device with backwashing is currently used to filter and remove impurities from the process fluid. However, during application, the process fluid of in-situ leaching mines usually exhibits the characteristics of large flow and high pressure, and due to the small particle size of the filtered particles (above 5μm), the liquid filtration resistance increases. Compared with fluid filtration processes in other industries such as coal mining, geothermal energy, and water conservancy, the processing fluid pressure of in-situ leaching mines is 3 to 7 times higher, reaching 0.6 to 1.5MPa. In addition, because the instantaneous inflow of fluid is large when the filter device is turned on, the impact pressure of the high-speed fluid on the filter element is high, so both metal filter elements with high pressure resistance and low-cost plastic filter elements are at great risk of being damaged by impact, resulting in failure of filtering capacity, resulting in a short effective service life of the filter element (only 1 to 7 days), frequent maintenance and replacement, reduced operating efficiency and increased application costs.

[0003] To address these issues, some companies have resorted to retaining reservoirs or intermediate containers. This involves initially filtering the fluid at low pressure and then increasing the pressure with pipeline pumps or booster pumps. While this buffers the fluid pressure, such measures fail to achieve the desired level of fine filtration and complicate the filtration process. Other companies have resorted to thickening the filter element framework or using impact-resistant materials for fine filtration devices, which not only increases equipment manufacturing costs but also yields suboptimal results. Therefore, it is necessary to develop a pressure-resistant protection solution for filter elements in fine filtration devices for in-situ uranium leaching processes to prevent damage from the impact of relatively high-pressure, high-flow fluids. Summary of the Invention

[0004] The purpose of the present invention is to provide a device and method for pressure-resistant protection of a filter element in a fine filtration device for a uranium in-situ leaching process fluid, thereby preventing damage to the filter element caused by the impact of relatively high-pressure, high-flow fluids, and thus solving the problems of the above-mentioned existing filter element pressure-resistant measures resulting in the complication of filtration equipment and processes and the increase in equipment manufacturing costs.

[0005] To achieve the above object, the present invention provides the following solutions:

[0006] The present invention provides a pressure-resistant protective device for a fluid filter element in an in-situ leaching uranium mining process, comprising:

[0007] A fluid filtration device, comprising a filtration container and a cylindrical filter element disposed within the filtration container, wherein an annular cavity is formed between the outer wall of the cylindrical filter element and the inner wall of the filtration container, and the axial ends of the annular cavity are sealed by a sealing structure; the filtration container is provided with a first liquid inlet, a second liquid inlet, a liquid discharge port, and an exhaust port, wherein the first liquid inlet is located on a side wall of the filtration container forming the annular cavity, the second liquid inlet, the liquid discharge port, and the exhaust port are all located on other side walls of the filtration container, and the exhaust port is provided with an exhaust valve;

[0008] a first branch, wherein a first damping structure is provided on the first branch, a first end of the first branch being connected to the first liquid inlet, and a second end being used for introducing high-pressure fluid; the first damping structure is used for initially reducing the pressure of the high-pressure fluid and allowing the initially reduced-pressure fluid to flow as a first fluid through the first branch into the annular cavity;

[0009] a second branch, wherein a second damping structure is provided on the second branch, a first end of the second branch is connected to the second liquid inlet, and a second end is connected to the first branch located between the first damping structure and the first liquid inlet, so as to introduce part of the fluid after the initial pressure reduction into the second branch, and the second damping structure is used to perform a secondary pressure reduction on the fluid after the initial pressure reduction, and make the fluid after the secondary pressure reduction flow as a second fluid diversion through the second branch into the interior of the cylindrical filter element, and the second fluid diversion and the first fluid diversion respectively and simultaneously reach the inner and outer walls of the cylindrical filter element, so that the pressure exerted by the second fluid diversion on the inner wall of the cylindrical filter element and the pressure exerted by the first fluid diversion on the outer wall of the cylindrical filter element offset each other, thereby reducing the impact force of the fluid on the cylindrical filter element;

[0010] A liquid discharge pipeline is connected to the liquid discharge port, and a pressure-controlled liquid discharge valve is provided on the liquid discharge pipeline.

[0011] Optionally, the first damping structure is a hydraulic damper.

[0012] Optionally, the second damping structure is a pulsation damper.

[0013] Optionally, the second liquid inlet and the drain port are both arranged at the bottom of the filter container, and the second liquid inlet and the drain port are arranged to overlap, the first end of the second branch is connected to the drain pipeline, and the connection between the second branch and the drain pipeline is located between the drain port and the pressure-controlled drain valve.

[0014] Optionally, valve structures are respectively provided on both sides of the second damping structure of the second branch.

[0015] Optionally, a flange gate valve is further provided on the first branch, and the flange gate valve and the first damping structure are arranged in sequence along the fluid flow direction. The flange gate valve is used to connect a high-pressure fluid pipeline to introduce the high-pressure fluid.

[0016] Optionally, the filtration container is a stainless steel container, and the cylindrical filter element is a polypropylene folded filter element, the filtration accuracy of which is 5μm or 10μm, and the pressure difference resistance strength of the skeleton is 0.1-0.3Mpa.

[0017] Optionally, the cylindrical filter element is supported in the filter container by a filter element support plate, the top of the cylindrical filter element is pressed by a pressure plate, the outer edge of the pressure plate is sealed to the inner wall of the filter container, and the pressure plate serves as the sealing structure to seal the top of the annular cavity; the outer edge of the filter element support plate is sealed to the inner wall of the filter container, a through hole is provided in the middle of the filter element support plate, and the position of the filter element support plate close to its outer edge serves as the sealing structure to seal the bottom of the annular cavity.

[0018] The present invention further provides a method for pressure-resistant protection of a fluid filter element in an in-situ uranium leaching process, which is implemented by using any one of the above-mentioned pressure-resistant protection devices for a fluid filter element in an in-situ uranium leaching process, comprising:

[0019] closing the pressure-controlled drain valve and the exhaust valve, and adjusting the parameters of the first damping structure and the second damping structure according to the pressure of the high-pressure fluid, so that the second fluid split flow and the first fluid split flow respectively and simultaneously reach the inner and outer walls of the cylindrical filter element, and the pressure exerted by the second fluid split flow on the inner wall of the cylindrical filter element and the pressure exerted by the first fluid split flow on the outer wall of the cylindrical filter element offset each other;

[0020] The second fluid flow and the first fluid flow are maintained to continue to reach the inner and outer walls of the cylindrical filter element respectively, so as to increase the internal pressure of the cylindrical filter element. After the internal pressure of the cylindrical filter element increases to a set exhaust pressure, the exhaust valve is opened to exhaust and relieve pressure. When the fluid flow rate in the second damping structure drops to within a set range, the exhaust valve is closed, and the fluid flows into the annular cavity through the first branch, and the fluid in the annular cavity is forced to enter the interior of the cylindrical filter element through the side wall of the cylindrical filter element, thereby completing the fluid filtration and increasing the internal pressure of the cylindrical filter element again.

[0021] After the internal pressure of the cylindrical filter element rises to the set discharge pressure, the pressure-controlled discharge valve is opened to discharge the filtered fluid through the discharge pipe.

[0022] Optionally, the set exhaust pressure is greater than 0.2 MPa, and the set liquid discharge pressure is greater than 0.3 MPa.

[0023] Compared with the prior art, the present invention has achieved the following technical effects:

[0024] The pressure-resistant protective device for a fluid filter element in an in-situ uranium leaching process, proposed in the present invention, features a rationally designed structure. By providing a first damping structure within the first branch, the high-pressure fluid is initially depressurized, reducing the impact force and slowing the rise in fluid pressure. A second branch is provided to divert the fluid within the first branch, allowing a portion of the initially depressurized fluid to enter the annular cavity directly from the first inlet and be filtered through the cylindrical filter element, while the remaining portion undergoes a secondary depressurization by the second damping structure and enters the interior of the cylindrical filter element through the second inlet. By adjusting the parameters of the first and second damping structures, the two fluid streams can be simultaneously or nearly simultaneously delivered to the inner and outer sides of the cylindrical filter element. The pressure-reducing effect of the first damping structure and the diversion effect of the second branch initially reduce the impact strength of the fluid on the filter element. The mutual offsetting effect of the fluid pressures inside and outside the filter element further reduces the pressure differential between the two sides of the filter element, significantly reducing the impact force of the fluid on the filter element. As the two diverted fluid streams flow in, the effect of the first damping structure gradually weakens, and the pressure of the two diverted fluid streams gradually increases. After the internal pressure of the filter element rises to the set exhaust pressure, the exhaust valve opens to release air until the fluid velocity in the second damping structure decreases to within the set range, achieving closure and reducing the fluid velocity in the second branch to zero. At this point, the fluid reaches the filter element through the first branch and the annular cavity, where it is filtered. Once the internal pressure of the filter element rises to the set discharge pressure, the pressure-controlled drain valve opens to drain the fluid. The fluid then follows the normal filtration path (first reaching the annular cavity, then passing through the filter element's sidewalls to reach the interior), eliminating the impact force when the fluid initially enters the filter element.

[0025] In summary, the pressure-resistant protection device for the filter element of the in-situ uranium leaching process fluid of the present invention is used to provide pressure-resistant protection for the filter element in the in-situ uranium leaching process fluid fine filtration device. By setting a branch diversion and setting a damping structure on both branches, it can not only reduce the impact intensity of the high-pressure fluid on the filter element, but also prevent the damage caused by the impact of relatively high-pressure and large-flow fluid on the filter element, thereby achieving the purpose of protecting the filter element structure, extending the service life of the filter element, reducing costs and increasing efficiency, and the operating process is simple, so that the in-situ leaching fine filtration device can operate stably for a long time, solving a prominent technical difficulty in the in-situ uranium leaching fine filtration process, and is suitable for liquid filtration with a certain pressure or flow rate, especially for in-situ uranium leaching production.

[0026] The pressure-resistant protection method for fluid filter elements in an in-situ leaching uranium mining process proposed in the present invention reduces the impact strength of high-pressure fluid on the filter element, extends the service life of the filter element, enables the in-situ leaching fine filtration device to operate stably for a long time, and effectively reduces the application cost of the fine filter. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0028] Figure 1 This is a schematic diagram of the overall structure of the pressure-resistant protection device for the fluid filter element in the in-situ leaching uranium process disclosed in an embodiment of the present invention.

[0029] Wherein, the accompanying drawings are marked as follows:

[0030] 100. Pressure-resistant protection device for fluid filter element in in-situ leaching uranium process;

[0031] 1. Filter container; 2. Cylindrical filter element; 3. Annular cavity; 4. First liquid inlet; 5. First branch; 6. First damping structure; 7. Second branch; 8. Second damping structure; 9. Drain port; 10. Drain line; 11. Pressure-controlled drain valve; 12. Valve structure; 13. Flange gate valve; 14. Filter element support plate; 15. Pressure plate; 16. Exhaust valve. DETAILED DESCRIPTION

[0032] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0033] One of the objectives of the present invention is to provide a pressure-resistant protective device for a fluid filter element in an in-situ leaching uranium mining process, which can prevent damage to the filter element caused by the impact of relatively high-pressure, high-flow fluids, thereby solving the problems of the above-mentioned existing filter element pressure-resistant measures resulting in the complication of filtering equipment and processes and the increase in equipment manufacturing costs.

[0034] Another object of the present invention is to provide a method for pressure-resistant protection of a fluid filter element in an in-situ uranium leaching process, which is implemented by the above-mentioned pressure-resistant protection device for a fluid filter element in an in-situ uranium leaching process, and can prevent damage to the filter element caused by the impact of relatively high-pressure and large-flow fluids.

[0035] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0036] Example 1

[0037] like Figure 1As shown, this embodiment provides a fluid filter element pressure protection device 100 for an in-situ leaching uranium process, which mainly includes a fluid filtering device, a first branch 5, a second branch 7, a drainage pipeline 10, a first damping structure 6 and a second damping structure 8. The fluid filtering device includes a filter container 1 and a cylindrical filter element 2 arranged in the filter container 1, an annular cavity 3 is formed between the outer wall of the cylindrical filter element 2 and the inner wall of the filter container 1, and the axial ends of the annular cavity 3 are sealed by a sealing structure. The sealing structures at the axial ends of the annular cavity 3 will limit the flow of fluid, so that the fluid entering the annular cavity 3 from the outside of the container can only pass through the side wall of the cylindrical filter element 2 along the radial direction of the cylindrical filter element 2, thereby completing fluid filtration. The filter container 1 is provided with a first liquid inlet 4, a second liquid inlet, a liquid discharge port 9 and an exhaust port, wherein the first liquid inlet 4 is located on the side wall of the filter container 1 forming the annular cavity 3, and the second liquid inlet, the liquid discharge port 9 and the exhaust port are all located on other positions of the side wall of the filter container 1, that is, the second liquid inlet, the liquid discharge port 9 and the exhaust port are all arranged away from the annular cavity 3. In the embodiment, as Figure 1 As shown, the first liquid inlet 4 is arranged on the side wall of the filter container 1, the exhaust port is arranged on the container cover at the top of the filter container 1, and the exhaust port is provided with an exhaust valve 16; the drain port 9 and the second liquid inlet are both arranged at the bottom of the filter container 1, and the drain port 9 and the second liquid inlet are arranged to overlap, that is, a through opening is opened at the bottom of the filter container 1, which serves as both the drain port 9 and the second liquid inlet. The first branch 5 is provided with a first damping structure 6, the first end of the first branch 5 is connected to the first liquid inlet 4, the second end of the first branch 5 is used to introduce high-pressure fluid, the first damping structure 6 is used to initially reduce the pressure of the high-pressure fluid, and the fluid after the initial pressure reduction is diverted through the first branch 5 into the annular cavity 3 as the first fluid; the second branch 7 is provided with a second damping structure 8, the first end of the second branch 7 is connected to the second liquid inlet, and the second end of the second branch 7 is connected to the first branch 5 located between the first damping structure 6 and the first liquid inlet 4, so as to introduce part of the fluid after the initial pressure reduction into the second branch 7, the second damping structure 8 is used to perform a secondary pressure reduction on the fluid after the initial pressure reduction, and the fluid after the secondary pressure reduction is diverted through the second branch as the second fluid 7 enters the interior of the cylindrical filter element 2, and the second fluid diversion and the first fluid diversion reach the inner and outer walls of the cylindrical filter element 2 respectively and simultaneously, so that the pressure exerted by the second fluid diversion on the inner wall of the cylindrical filter element 2 and the pressure exerted by the first fluid diversion on the outer wall of the cylindrical filter element 2 offset each other, thereby reducing the impact force of the fluid on the cylindrical filter element 2. The "pressure exerted by the second fluid diversion on the inner wall of the cylindrical filter element and the pressure exerted by the first fluid diversion on the outer wall of the cylindrical filter element offset each other" emphasized in the present technical solution does not mean that the pressure exerted by the second fluid diversion on the inner wall of the cylindrical filter element and the pressure exerted by the first fluid diversion on the outer wall of the cylindrical filter element completely offset each other, but partially offset, that is, the inner wall of the cylindrical filter element is supported by the second fluid diversion to reduce the pressure difference between the inner and outer walls of the cylindrical filter element.

[0038] Since the second liquid inlet and the liquid outlet 9 share a common opening, Figure 1 As shown, drain line 10 is connected in parallel with the first end of second branch line 7 and then in series with drain port 9 (second liquid inlet). A pressure-controlled drain valve 11 is provided on drain line 10. The connection between the first end of second branch line 7 and drain line 10 is located between drain port 9 (second liquid inlet) and pressure-controlled drain valve 11. Pressure-controlled drain valve 11 slowly opens electronically when the internal pressure of the filter element reaches a certain level, discharging the filtrate. The pressure-resistant protective device 100 for the fluid filter element in the in-situ uranium leaching process prevents damage to the filter element caused by the initial impact of relatively high-pressure, high-flow fluids, thereby protecting the filter element structure, extending the filter element's service life, and reducing costs and increasing efficiency.

[0039] In this embodiment, the first damping structure 6 is preferably a hydraulic damper, specifically a hydraulic damper with an automatic control circuit. The damping hardness is automatically adjusted in a positive correlation with the water pressure. This damping structure provides water hammer reduction, hysteresis, and damping, reducing peak pressure upon the entry of high-pressure fluid, thereby reducing fluid pressure. The damping effect ceases once the fluid flows steadily.

[0040] In this embodiment, the aforementioned second damping structure 8 is preferably a pulse damper, specifically a low-pulse-resistance damping structure, which has the function of buffering the impact pressure of water flow. When the fluid velocity in the pipeline drops to a set range, the damping structure is locked, and the fluid velocity is zero after locking.

[0041] In this embodiment, the exhaust valve 16 is preferably a pressure-adjustable exhaust valve, which opens to exhaust when the set pressure in the filter container 1 is reached. After the gas is exhausted, the valve closes to discharge the filtered fluid.

[0042] In this embodiment, a T-shaped pipe structure is formed between the second branch 7 and the first branch 5. The second branch 7 is also provided with a valve structure 12 on at least one side of the second damping structure 8 to control the opening and closing of the second branch 7. Figure 1 As shown, as a preferred solution, in this embodiment, valve structures 12 are provided on both sides of the second damping structure 8 .

[0043] In this embodiment, a flange gate valve 13 is also provided on the first branch 5. The flange gate valve 13 and the first damping structure 6 are arranged in sequence along the fluid flow direction. The flange gate valve 13 is arranged close to the liquid inlet of the first branch 5. The flange gate valve 13 is used to connect the high-pressure fluid pipeline to introduce the high-pressure fluid into the first branch 5.

[0044] In this embodiment, the filter container 1 is preferably a stainless steel pressure-resistant container, such as 316L stainless steel, which can withstand a pressure of about 10 MPa. The cylindrical filter element 2 is preferably a polypropylene (PP) folded filter element with a skeleton thickness of 2mm to 5mm, a filtration accuracy of 5μm or 10μm, and a designed filtration flow rate of 10m 3 / h, the pressure difference strength of the skeleton can be 0.1-0.3Mpa, preferably 0.2Mpa.

[0045] In this embodiment, the cylindrical filter element 2 is supported in the filter container 1 by the filter element support plate 14, the top of the cylindrical filter element 2 is pressed by the pressure plate 15, the outer edge of the pressure plate 15 is sealed with the inner wall of the filter container 1, and the pressure plate 15 serves as a sealing structure to seal the top of the annular cavity 3; the outer edge of the filter element support plate 14 is sealed with the inner wall of the filter container 1, a through hole is opened in the middle of the filter element support plate 14, and the position of the filter element support plate 14 near its outer edge serves as a sealing structure to seal the bottom of the annular cavity 3.

[0046] The pressure protection method for a fluid filter element in an in-situ uranium leaching process implemented by the above-mentioned pressure protection device 100 for a fluid filter element in an in-situ uranium leaching process mainly includes the following steps:

[0047] Close the pressure-controlled drain valve 11 and the exhaust valve 16, and adjust the parameters of the first damping structure 6 and the second damping structure 8 according to the pressure of the high-pressure fluid, so that the second fluid diversion and the first fluid diversion reach the inner and outer walls of the cylindrical filter element 2 respectively and simultaneously, and the pressure exerted by the second fluid diversion on the inner wall of the cylindrical filter element 2 and the pressure exerted by the first fluid diversion on the outer wall of the cylindrical filter element 2 offset each other;

[0048] The second fluid flow and the first fluid flow are maintained to continue to reach the inner and outer walls of the cylindrical filter element 2 respectively, so that the internal pressure of the cylindrical filter element 2 is increased. After the internal pressure of the cylindrical filter element 2 is increased to the set exhaust pressure, the exhaust valve 16 is opened to exhaust and relieve the pressure. When the fluid flow rate in the second damping structure 8 drops to within the set range, the exhaust valve 16 is closed to allow the fluid to flow into the annular cavity 3 through the first branch 5, and the fluid in the annular cavity 3 is forced to enter the interior of the cylindrical filter element 2 through the side wall of the cylindrical filter element 2, completing the fluid filtration and increasing the internal pressure of the cylindrical filter element 2 again.

[0049] After the internal pressure of the cylindrical filter element 2 rises to the set discharge pressure, the pressure-controlled discharge valve 11 is opened to discharge the filtered fluid through the discharge pipe.

[0050] The following is a detailed description of the implementation process of the filter element pressure protection method (process) in this embodiment with reference to specific examples:

[0051] (I) Pipeline connection and installation. Connect the external high-pressure fluid pipeline inlet to the flange gate valve 13. The flange gate valve 13 is initially in the closed state, and the first damping structure 6, the second damping structure 8, the exhaust valve 16 and the pressure-controlled drain valve 11 are in the initial adjustment state.

[0052] (2) Pressure resistance protection control. According to the inlet high-pressure fluid pressure, set the parameters of the first damping structure 6, open the flange gate valve 13 to allow the high-pressure fluid to pass through the first damping structure 6; after the fluid is depressurized and delayed by the water pressure fluctuations through the first damping structure 6, a part of the fluid passes through the first branch 5 directly into the annular cavity 3 of the first liquid inlet 4 on the side of the filter container 1, and the other part of the fluid passes through the second damping structure 8 to buffer the pressure again, and then enters the internal space of the cylindrical filter element 2 from bottom to top through the discharge port 9 (second liquid inlet) at the lower end of the filter container 1 through the holes on the filter element support plate 14, playing a role in resisting the impact of the fluid in the peripheral space of the cylindrical filter element 2 ; When the water flow velocity in the second damping structure 8 drops to within the set range, the second damping structure 8 is locked. After locking, the fluid flow velocity of the second branch 7 is zero. At this time, the fluid continues to flow into the annular cavity 3 through the first branch 5 for filtration. After the internal pressure of the cylindrical filter element 2 rises to the set exhaust pressure, the upper adjustable exhaust valve 16 is exhausted until the exhaust valve 16 is closed after the liquid is discharged; the internal pressure of the cylindrical filter element 2 continues to rise. After rising to the set discharge pressure, the pressure-controlled discharge valve 11 is opened, and the filtered fluid flows out of the filter container 1 from top to bottom through the holes on the filter element support plate 14 for normal filtration.

[0053] (III) Parameter setting of pressure-resistant protective components. During the fluid filtration process, according to the different inlet high-pressure fluid pressures, the parameters of the first damping structure 6 and the locking flow rate of the second damping structure 8 are adjusted accordingly to control the time and flow rate of the fluid diversion to the inside and outside of the filter element, thereby reducing the internal and external pressure difference and pressure peak fluctuations at the initial stage of the fluid entering the filter element; adjusting the appropriate exhaust pressure of the exhaust valve 16 can make the inside of the filter element have a certain pressure to prevent the pressure from being discharged too quickly and causing large pressure difference fluctuations; adjusting the appropriate discharge pressure of the pressure-controlled drain valve 11, and making it higher than the exhaust pressure of the exhaust valve 16, ensures that a certain pressure is maintained inside the filter element, thereby reducing the pressure difference between the inside and outside of the filter element during the filtration process.

[0054] (IV) Pressure-resistant protection mechanism and process. The inlet high-pressure fluid pressure is about 0.9MPa. The parameters of the first damping structure 6 are set to the safest value. The flange gate valve 13 is opened to allow the fluid to pass through the first damping structure 6. After the high-pressure fluid at the pipeline inlet is acted upon by the first damping structure 6, the fluid impact force is reduced and the fluid pressure rise is slowed down. After the fluid is diverted through the second branch 7, a part of it directly enters the filter element from the first branch 5 for filtration, and the other part enters the filter element from the bottom of the filter container 1 through the second damping structure 8 on the second branch 7. By adjusting the parameters of the first damping structure 6 and the second damping structure 8, the two diversions can be made to reach the inside and outside of the cylindrical filter element 2 almost at the same time. The diversion effect of the fluid initially reduces the impact strength of the fluid on the cylindrical filter element 2, and the mutual offset of the fluid pressures inside and outside the cylindrical filter element 2 is further reduced. The pressure difference between the inside and outside of the cylindrical filter element 2 is lowered, which can significantly reduce the impact force of the fluid on the filter element; then the effect of the first damping structure 6 gradually weakens, and the fluid pressure of the two branches gradually increases. After the internal pressure of the cylindrical filter element 2 rises to the set exhaust pressure, the upper exhaust valve 16 opens to exhaust, and the exhaust valve 16 closes after the exhaust is completed; at this time, the second damping structure 8 is locked because the fluid velocity of its second branch 7 is reduced to the set range, and the fluid flow rate on the second branch 7 is zero. The fluid enters the filter container 1 from the first liquid inlet 4 through the first branch 5 and flows through the cylindrical filter element 2. After the internal pressure of the cylindrical filter element 2 rises to the set discharge pressure, the pressure-controlled discharge valve 11 opens for discharge; the fluid performs normal filtering, thereby eliminating the impact force when the fluid begins to enter the cylindrical filter element 2.

[0055] Under normal circumstances, in the initial state where fluid enters both the inside and outside of the cylindrical filter element 2, the initial pressure differential between the inside and outside of the cylindrical filter element 2 can be controlled within 0.2 MPa based on the pressure changes in the space inside and outside the cylindrical filter element 2. The exhaust valve 16 is adjusted to allow the internal pressure of the cylindrical filter element 2 to rise above 0.2 MPa, and then exhaust is performed. When the internal pressure of the cylindrical filter element 2 rises to 0.3 MPa, the first damping structure 6 is locked, and the pressure-controlled drain valve 11 is adjusted to open and drain the fluid. At this point, the internal and external pressure differential of the filter container 1 is approximately 0.1 MPa. No damage to the filter element was observed during six months of normal filtration. The filter element replacement cycle has been extended from approximately once every seven days to approximately once every 120 days, primarily due to the continuous decrease in the filter element's dirt holding capacity during use.

[0056] Thus, the fine filter element pressure protection device and method described in this embodiment are used for fine filtration of fluids during in-situ uranium leaching and to protect filter elements from damage caused by fluid impact. During the application of this pressure-resistant device, the rational setting of its various functional damping structures and parameters, combined with effective control of other pressure components, can effectively reduce the impact strength of high-pressure fluids on the filter element, extend the service life of the filter element, and maintain stable operation of the fine filtration device for a long period of time. This filter element pressure protection device and method demonstrate safety, practicality, stability, and convenience, meeting the pressure protection requirements for filter elements during fine filtration.

[0057] It should be noted that it is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention. Therefore, from all perspectives, the embodiments should be regarded as illustrative and non-restrictive, and the scope of the present invention is defined by the appended claims rather than the foregoing description. It is intended that all changes that fall within the meaning and range of equivalents of the claims be included in the present invention, and any reference signs in the claims should not be construed as limiting the claims to which they relate.

[0058] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only intended to help understand the method and core concept of the present invention. At the same time, those skilled in the art will find that the specific implementation methods and application scopes may vary based on the concept of the present invention. In summary, the contents of this specification should not be construed as limiting the present invention.

Claims

1. A pressure-resistant protective device for a fluid filter element in an in-situ leaching uranium mining process, characterized in that: include: A fluid filtration device, comprising a filtration container and a cylindrical filter element disposed within the filtration container, wherein an annular cavity is formed between the outer wall of the cylindrical filter element and the inner wall of the filtration container, and the axial ends of the annular cavity are sealed by a sealing structure; the filtration container is provided with a first liquid inlet, a second liquid inlet, a liquid discharge port, and an exhaust port, wherein the first liquid inlet is located on a side wall of the filtration container forming the annular cavity, the second liquid inlet, the liquid discharge port, and the exhaust port are all located on other side walls of the filtration container, and the exhaust port is provided with an exhaust valve; a first branch, wherein a first damping structure and a flange gate valve are provided on the first branch, a first end of the first branch being connected to the first liquid inlet, the flange gate valve and the first damping structure being arranged sequentially along a fluid flow direction, the flange gate valve being used to connect to a high-pressure fluid pipeline to introduce high-pressure fluid into the first branch; the first damping structure being used to initially reduce the pressure of the high-pressure fluid and divert the initially reduced pressure fluid as a first fluid through the first branch into the annular cavity; a second branch, wherein a second damping structure and a valve structure are provided on the second branch, and the valve structures are respectively provided on both sides of the second damping structure, the first end of the second branch is connected to the second liquid inlet, and the second end is connected to the first branch located between the first damping structure and the first liquid inlet, so as to introduce part of the fluid after the initial pressure reduction into the second branch, and the pressure reducing effect of the first damping structure and the diversion effect of the second branch on the fluid can preliminarily reduce the impact strength of the fluid on the cylindrical filter element; the second damping structure is used to perform a secondary pressure reduction on the fluid after the initial pressure reduction, and make the fluid after the secondary pressure reduction enter the interior of the cylindrical filter element as a second fluid diversion through the second branch, and the second fluid diversion and the first fluid diversion respectively and simultaneously reach the inner and outer walls of the cylindrical filter element, so that the pressure exerted by the second fluid diversion on the inner wall of the cylindrical filter element and the pressure exerted by the first fluid diversion on the outer wall of the cylindrical filter element offset each other, thereby reducing the impact force of the fluid on the cylindrical filter element when it begins to enter the cylindrical filter element; A drain pipeline, the drain pipeline is connected to the drain port, and a pressure-controlled drain valve is provided on the drain pipeline; as the second fluid diversion and the first fluid diversion flow into the cylindrical filter element, the effect of the first damping structure gradually weakens, and the fluid pressure of the second fluid diversion and the first fluid diversion gradually increases. After the internal pressure of the cylindrical filter element rises to the set exhaust pressure, the exhaust valve opens to exhaust until the fluid velocity of the second damping structure drops to within the set range, achieving closure, and the fluid flow rate in the second branch is reduced to zero; thereafter, the fluid reaches and flows through the cylindrical filter element through the first branch and the annular cavity in turn for filtration. After the internal pressure of the cylindrical filter element rises to the set discharge pressure, the pressure-controlled drain valve is opened to discharge the filtered fluid through the drain pipeline.

2. The pressure-resistant protective device for a fluid filter element in an in-situ leaching uranium mining process according to claim 1, characterized in that: The first damping structure is a hydraulic damper.

3. The pressure-resistant protective device for a fluid filter element in an in-situ leaching uranium mining process according to claim 1, characterized in that: The second damping structure is a pulsation damper.

4. The pressure-resistant protective device for a fluid filter element in an in-situ leaching uranium mining process according to any one of claims 1 to 3, characterized in that: The second liquid inlet and the liquid discharge port are both arranged at the bottom of the filter container, and the second liquid inlet and the liquid discharge port are arranged to overlap, the first end of the second branch is connected to the liquid discharge pipeline, and the connection between the second branch and the liquid discharge pipeline is located between the liquid discharge port and the pressure-controlled liquid discharge valve.

5. The pressure-resistant protective device for a fluid filter element in an in-situ leaching uranium mining process according to any one of claims 1 to 3, characterized in that: The filter container is a stainless steel container, the cylindrical filter element is a polypropylene folded filter element, the filtration accuracy is 5μm or 10μm, and the pressure difference resistance strength of the skeleton is 0.1-0.3Mpa.

6. The pressure-resistant protective device for a fluid filter element in an in-situ leaching uranium mining process according to any one of claims 1 to 3, characterized in that: The cylindrical filter element is supported in the filter container by a filter element support plate, the top of the cylindrical filter element is pressed by a pressure plate, the outer edge of the pressure plate is sealed with the inner wall of the filter container, and the pressure plate serves as a sealing structure to seal the top of the annular cavity; the outer edge of the filter element support plate is sealed with the inner wall of the filter container, a through hole is opened in the middle of the filter element support plate, and the position of the filter element support plate close to its outer edge serves as the sealing structure to seal the bottom of the annular cavity.

7. A method for pressure protection of a fluid filter element in an in-situ uranium leaching process using the pressure protection device for a fluid filter element in an in-situ uranium leaching process according to any one of claims 1 to 6, characterized in that: include: closing the pressure-controlled drain valve and the exhaust valve, and adjusting the parameters of the first damping structure and the second damping structure according to the pressure of the high-pressure fluid, so that the second fluid split flow and the first fluid split flow respectively and simultaneously reach the inner and outer walls of the cylindrical filter element, and the pressure exerted by the second fluid split flow on the inner wall of the cylindrical filter element and the pressure exerted by the first fluid split flow on the outer wall of the cylindrical filter element offset each other; The second fluid flow and the first fluid flow are maintained to continue to reach the inner and outer walls of the cylindrical filter element respectively, so as to increase the internal pressure of the cylindrical filter element. After the internal pressure of the cylindrical filter element increases to a set exhaust pressure, the exhaust valve is opened to exhaust and relieve pressure. When the fluid flow rate in the second damping structure drops to within a set range, the exhaust valve is closed, and the fluid flows into the annular cavity through the first branch, and the fluid in the annular cavity is forced to enter the interior of the cylindrical filter element through the side wall of the cylindrical filter element, thereby completing the fluid filtration and increasing the internal pressure of the cylindrical filter element again. After the internal pressure of the cylindrical filter element rises to the set discharge pressure, the pressure-controlled discharge valve is opened to discharge the filtered fluid through the discharge pipe.

8. The pressure-resistant protection method for a fluid filter element in an in-situ leaching uranium mining process according to claim 7, characterized in that: The set exhaust pressure is greater than 0.2 MPa, and the set liquid discharge pressure is greater than 0.3 MPa.

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