Ionic rare earth short-process integrated membrane separation, enrichment and concentration device and preparation system

Abstract

The utility model provides a short-process integrated membrane separation, enrichment and concentration device for ionic rare earth, and belongs to the technical field of rare earth preparation. The device comprises a nanofiltration transfer water tank, a nanofiltration membrane treatment system, a first-stage reverse osmosis transfer water tank, a first-stage low-pressure reverse osmosis membrane treatment system, a second-stage reverse osmosis transfer water tank, a second-stage medium-pressure reverse osmosis membrane treatment system, a third-stage reverse osmosis transfer water tank and a third-stage high-pressure reverse osmosis membrane treatment system which are communicated in sequence, a fourth-stage reverse osmosis transfer water tank and a fourth-stage ultrahigh-pressure reverse osmosis membrane treatment system. According to the utility model, the nanofiltration membrane and the multi-stage reverse osmosis membrane are integrated, so that rare earth ions are concentrated stage by stage to meet the extraction and purification requirements, no additional chemical deslagging agent, chemical precipitating agent and flocculating agent are added, no reaction tank for chemical impurity removal, chemical precipitation and secondary acid dissolution needs to be built, and the integrated membrane treatment adopts full-automatic operation, so that a large amount of labor is saved; and plate and frame filtration before an extraction process and an acid dissolution process at a rear section are not needed, so that the generation of salt-containing wastewater is reduced.

Description

Technical Field

[0001] This utility model relates to the field of rare earth preparation technology, and in particular to an integrated membrane separation enrichment and concentration device for short-process ionic rare earth and a preparation system for ionic rare earth including the integrated membrane separation enrichment and concentration device. Background Technology

[0002] The traditional mining, beneficiation, and smelting process for ion-adsorption rare earth ores involves in-situ leaching (manually stripping mine vegetation, drilling holes, injecting sulfate leaching agents, and collecting the mother liquor) to obtain an ion-adsorption rare earth solution. Chemical beneficiation is then performed: first, low-concentration carbonates are used to remove silicon and aluminum impurities from the mother liquor; then, high-concentration carbonates are added to the supernatant to convert rare earth ions into rare earth carbonates; finally, flocculants are added to precipitate the rare earth carbonates, and the supernatant is separated and returned to the mine for leaching agent preparation. The rare earth carbonates precipitated at the bottom of the reaction tank flow into a rare earth concentration tank, where they undergo a second sedimentation to remove excess water. The precipitate is pumped into a plate and frame filter press, where solid rare earth carbonates are obtained after solid-liquid separation. Rare earth smelting: The rare earth carbonates are transported to the rare earth smelting workshop, dissolved in acid to obtain a rare earth ion solution, and then an extractant is added for rare earth extraction and separation. In the processes of rare earth mining, beneficiation, and smelting, the chemical beneficiation process requires the use of large quantities of chemical impurity removers and precipitants to convert rare earth ions into rare earth carbonate solids. Because the concentration of rare earth elements in the mother liquor from in-situ leaching is very low, large amounts of chemical impurity removers, precipitants, and flocculants are consumed. In the subsequent rare earth smelting process, large amounts of acid are needed to dissolve the rare earth carbonates into rare earth ions, which also generates a large amount of high-salinity wastewater.

[0003] In traditional ion-adsorption rare earth mining, beneficiation, and smelting processes, ion-adsorption rare earth elements are adsorbed into the rare earth mine soil in ionic form. After ion exchange with leaching agents, they transform from ions to solids and then back to ions, consuming large amounts of chemical impurity removers, precipitants, flocculants, and acids, and generating large quantities of high-salt wastewater. Furthermore, numerous chemical impurity removal and precipitation reaction tanks need to be constructed, requiring plate and frame filters and flocculants. In the chemical precipitation beneficiation section, extensive manual labor is required for operations such as testing the rare earth concentration in the reaction tanks, preparing the chemical precipitant, pumping the chemical precipitant, and pneumatic agitation. Crucially, manual operation is essential for determining the drainage time, which can lead to incomplete separation of precipitated rare earth carbonates, which flow out with the clean water and are returned to the leaching agent preparation. These rare earth carbonates are difficult to recover, resulting in rare earth loss and a reduced recovery rate. Therefore, new processes and methods are urgently needed.

[0004] Pressure-driven membrane separation technology is a recently developed new separation technology, represented by nanofiltration and reverse osmosis membranes. Using nanofiltration and reverse osmosis membranes, under the action of a high-pressure pump, water can be separated from brackish water, seawater, and wastewater containing heavy metal ions, achieving desalination of brackish water, freshwater production from seawater desalination, and reduction of heavy metal ion wastewater. Pressure-driven membrane separation technology has numerous applications in the resource recovery treatment of coal washing wastewater, brackish water softening, removal of harmful substances from drinking water, landfill leachate treatment, high-salinity wastewater treatment, circulating cooling water treatment, greywater reuse, wastewater treatment, and the recovery of high-value chemicals in the food, beverage, and pharmaceutical industries. There are few reports on the application of membrane separation technology to the separation and purification of ion-adsorption rare earth elements. However, integrated membrane technology can achieve the separation and concentration of rare earth elements in rare earth concentrate mother liquor. The membrane concentrate is directly connected to the extraction process, achieving the same effect as the traditional rare earth mining-benefiting-smelting process. Therefore, this short-process technology is indeed feasible. Utility Model Content

[0005] In view of this, the purpose of this utility model is to provide an integrated membrane separation, enrichment, and concentration device for ion-type rare earth short-process based on integrated membrane technology. By selecting different types of filter membranes, rare earth ions in the rare earth leachate are concentrated step by step until the concentration required for subsequent extraction, separation, and purification is reached. This completely replaces the traditional chemical precipitation for impurity removal, chemical precipitation of rare earth, secondary acid dissolution of the impurity residue, solid-liquid separation of the rare earth precipitation, and acid dissolution of the rare earth precipitation in subsequent smelting processes. This reduces the consumption of chemicals such as chemical impurity removers, chemical precipitants, and flocculants, and eliminates the need to construct chemical impurity removal, chemical precipitation, and acid dissolution tanks for impurity residue removal. By adopting integrated membrane technology, which integrates nanofiltration membranes and multi-stage reverse osmosis membranes, monovalent ions in the rare earth leachate can be removed, and divalent or trivalent rare earth ions can be concentrated step by step to the concentration required for extraction. The integrated membrane technology operates fully automatically, saving a significant amount of labor and greatly shortening the process flow of rare earth mining, beneficiation, and smelting.

[0006] To achieve the above objectives, this utility model provides the following technical solution:

[0007] An integrated membrane separation, enrichment, and concentration device for short-process ion-type rare earth elements includes a nanofiltration transfer tank, a nanofiltration membrane treatment system, a first-stage reverse osmosis transfer tank, a first-stage low-pressure reverse osmosis membrane treatment system, a second-stage reverse osmosis transfer tank, a second-stage medium-pressure reverse osmosis membrane treatment system, a third-stage reverse osmosis transfer tank, a third-stage high-pressure reverse osmosis membrane treatment system, a fourth-stage reverse osmosis transfer tank, and a fourth-stage ultra-high-pressure reverse osmosis membrane treatment system, all connected in sequence.

[0008] Preferably, it also includes an electrical control cabinet, which is used to control the manual and fully automatic operation of the integrated membrane separation enrichment and concentration device.

[0009] Preferably, the electrical control cabinet has a display screen, an automatic button, a manual button, and an emergency stop button;

[0010] The electrical control cabinet has a built-in PLC controller, IoT card, and mobile APP control module.

[0011] Preferably, it further includes:

[0012] A membrane cleaning agent tank is used to clean the integrated membrane separation, enrichment, and concentration device.

[0013] Preferably, each of the nanofiltration transfer tank, the first-stage reverse osmosis transfer tank, the second-stage reverse osmosis transfer tank, the third-stage reverse osmosis transfer tank, and the fourth-stage reverse osmosis transfer tank is equipped with a level gauge.

[0014] Preferably, the level gauge is a magnetic float level gauge.

[0015] Preferably, the nanofiltration membrane treatment system, the first-stage low-pressure reverse osmosis membrane treatment system, the second-stage medium-pressure reverse osmosis membrane treatment system, the third-stage high-pressure reverse osmosis membrane treatment system, and the fourth-stage ultra-high-pressure reverse osmosis membrane treatment system are respectively a nanofiltration membrane stack, a first-stage reverse osmosis membrane stack, a second-stage reverse osmosis membrane stack, a third-stage reverse osmosis membrane stack, and a fourth-stage reverse osmosis membrane stack.

[0016] Preferably, low-pressure protection switches and high-pressure protection switches are provided between the nanofiltration transfer tank and the nanofiltration membrane treatment system, between the first-stage reverse osmosis transfer tank and the first-stage low-pressure reverse osmosis membrane treatment system, between the second-stage reverse osmosis transfer tank and the second-stage medium-pressure reverse osmosis membrane treatment system, between the third-stage reverse osmosis transfer tank and the third-stage high-pressure reverse osmosis membrane treatment system, and between the fourth-stage reverse osmosis transfer tank and the fourth-stage ultra-high-pressure reverse osmosis membrane treatment system.

[0017] Preferably, the driving force between the nanofiltration transfer tank and the nanofiltration membrane treatment system, between the first-stage reverse osmosis transfer tank and the first-stage low-pressure reverse osmosis membrane treatment system, between the second-stage reverse osmosis transfer tank and the second-stage medium-pressure reverse osmosis membrane treatment system, between the third-stage reverse osmosis transfer tank and the third-stage high-pressure reverse osmosis membrane treatment system, and between the fourth-stage reverse osmosis transfer tank and the fourth-stage ultra-high-pressure reverse osmosis membrane treatment system is provided by pumps.

[0018] On the other hand, this utility model also provides an ionic rare earth short-process preparation system, including the above-mentioned integrated membrane separation enrichment and concentration device for ionic rare earth short-process preparation.

[0019] Compared with the prior art, this utility model has the following beneficial effects:

[0020] By directly integrating nanofiltration membranes and reverse osmosis, rare earth ions in rare earth leachate are concentrated step-by-step, replacing chemical impurity removal, chemical precipitation, secondary acid dissolution and precipitation of impurity residue, flocculation, plate and frame filtration, and the preparation tanks for chemical impurity removal agents and chemical precipitants, as well as manual labor, agitators, and pumping systems. This reduces the consumption of chemicals such as chemical impurity removal agents, chemical precipitants, and flocculants. It also eliminates the need to construct reaction tanks for chemical impurity removal, chemical precipitation, and secondary acid dissolution of impurity residue, reducing infrastructure investment. The rare earth ions concentrated by the integrated membrane are directly sent to the smelting and extraction section, eliminating the need for plate and frame filtration and acid dissolution of rare earth precipitation, thus reducing the discharge of high-salt wastewater. This significantly shortens the process flow of rare earth mining, beneficiation, and smelting. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0022] Figure 2 This is a schematic diagram of the external structure of the electrical control cabinet;

[0023] In the diagram, 0 is the rare earth mother liquor; 1 is the nanofiltration transfer tank; 2 is the first level gauge; 3 is the nanofiltration pump; 4 is the first electric three-way ball valve; 5 is the nanofiltration membrane treatment system; 6 is the second electric three-way ball valve; 7 is the first-stage reverse osmosis transfer tank; 8 is the second level gauge; 9 is the first-stage reverse osmosis pump; 10 is the third electric three-way ball valve; 11 is the first-stage low-pressure reverse osmosis membrane treatment system; 12 is the fourth electric three-way ball valve; 13 is the second-stage reverse osmosis transfer tank; 14 is the third level gauge; 15 is the second-stage reverse osmosis pump; 16 is the fifth electric three-way ball valve; 17 is the second-stage medium-pressure reverse osmosis membrane treatment system; 18 is the sixth electric three-way ball valve; 19 is the third-stage reverse osmosis transfer tank; 20 is the fourth level gauge; 21 is the third-stage reverse osmosis pump; and 22 is the seventh electric three-way ball valve. 23. Three-stage high-pressure reverse osmosis membrane treatment system; 24. Eighth electric three-way ball valve; 25. Fourth-stage reverse osmosis transfer tank; 26. Fifth level gauge; 27. Fourth-stage reverse osmosis pump; 28. Ninth electric three-way ball valve; 29. ​​Fourth-stage ultra-high-pressure reverse osmosis membrane treatment system; 30. Tenth electric three-way ball valve; 31. Rare earth concentrate discharge valve; 32. Membrane cleaning agent tank; 33. Eleventh electric three-way ball valve; 34. Membrane cleaning pump; 35. Membrane cleaning agent return pipeline; 36. Electrical control cabinet; 37. Display screen; 38. Automatic button; 39. Manual button; 40. Emergency stop button; 41. PLC controller; 42. IoT card; 43. Mobile APP control module; a. Low-pressure protection switch; b. High-pressure protection switch. Detailed Implementation

[0024] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present utility model without creative effort are within the protection scope of the present utility model.

[0025] In the description of this utility model, it should be noted that the terms "upper," "lower," "inner," "outer," "top / bottom," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0026] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installed," "equipped with," "sleeved / connected," "connected," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0027] like Figure 1-2 As shown, this utility model provides an integrated membrane separation, enrichment, and concentration device for short-process ion-type rare earth elements, comprising a nanofiltration transfer tank 1, a nanofiltration membrane treatment system 5, a first-stage reverse osmosis transfer tank 7, a first-stage low-pressure reverse osmosis membrane treatment system 11, a second-stage reverse osmosis transfer tank 13, a second-stage medium-pressure reverse osmosis membrane treatment system 17, a third-stage reverse osmosis transfer tank 19, a third-stage high-pressure reverse osmosis membrane treatment system 23, a fourth-stage reverse osmosis transfer tank 25, and a fourth-stage ultra-high-pressure reverse osmosis membrane treatment system 29, all connected in sequence.

[0028] The nanofiltration intermediate water tank 1 is equipped with a first level gauge 2. The nanofiltration intermediate water tank 1 and the nanofiltration membrane treatment system 5 are sequentially connected to a nanofiltration pump 3 and a first electric three-way ball valve 4. A low-pressure protection switch a and a high-pressure protection switch b are also provided. The nanofiltration membrane treatment system 5 and the first-stage reverse osmosis intermediate water tank 7 are connected by a second electric three-way ball valve 6.

[0029] A second level gauge 8 is installed on the primary reverse osmosis transfer tank 7. A primary reverse osmosis pump 9 and a third electric three-way ball valve 10 are sequentially connected between the primary reverse osmosis transfer tank 7 and the primary low-pressure reverse osmosis membrane treatment system 11. A low-pressure protection switch a and a high-pressure protection switch b are also installed. A fourth electric three-way ball valve 12 connects the primary low-pressure reverse osmosis membrane treatment system 11 and the secondary reverse osmosis transfer tank 13.

[0030] A third level gauge 14 is installed on the secondary reverse osmosis transfer tank 13. A secondary reverse osmosis pump 15 and a fifth electric three-way ball valve 16 are sequentially connected between the secondary reverse osmosis transfer tank 13 and the secondary medium-pressure reverse osmosis membrane treatment system 17. A low-pressure protection switch a and a high-pressure protection switch b are also installed. A sixth electric three-way ball valve 18 connects the secondary medium-pressure reverse osmosis membrane treatment system 17 and the tertiary reverse osmosis transfer tank 19.

[0031] The third-stage reverse osmosis transfer tank 19 is equipped with a fourth level gauge 20. The third-stage reverse osmosis transfer tank 19 is sequentially connected to the second-stage high-pressure reverse osmosis membrane treatment system by a third-stage reverse osmosis pump 21 and a seventh electric three-way ball valve 22. A low-pressure protection switch a and a high-pressure protection switch b are also provided. The third-stage high-pressure reverse osmosis membrane treatment system 23 is connected to the fourth-stage reverse osmosis transfer tank 25 by an eighth electric three-way ball valve 24.

[0032] The fourth-stage reverse osmosis transfer tank 25 is equipped with a fifth level gauge 26. The fourth-stage reverse osmosis transfer tank 25 and the fourth-stage ultra-high pressure reverse osmosis membrane treatment system 29 are sequentially connected by a fourth-stage reverse osmosis pump 27 and a ninth electric three-way ball valve 28. A low-pressure protection switch a and a high-pressure protection switch b are also provided. The fourth-stage high-pressure reverse osmosis membrane treatment system and the fourth-stage reverse osmosis transfer tank 25 are connected by a tenth electric three-way ball valve 30.

[0033] The first level gauge 2, the second level gauge 8, the third level gauge 14, the fourth level gauge 20 and the fifth level gauge 26 mentioned above are all preferably magnetic float level gauges.

[0034] The nanofiltration membrane treatment system 5, the first-stage low-pressure reverse osmosis membrane treatment system 11, the second-stage medium-pressure reverse osmosis membrane treatment system 17, the third-stage high-pressure reverse osmosis membrane treatment system 23, and the fourth-stage ultra-high-pressure reverse osmosis membrane treatment system 29 mentioned above are respectively nanofiltration membrane stack, first-stage reverse osmosis membrane stack, second-stage reverse osmosis membrane stack, third-stage reverse osmosis membrane stack, and fourth-stage reverse osmosis membrane stack.

[0035] In the aforementioned nanofiltration membrane treatment system 5, the first-stage low-pressure reverse osmosis membrane treatment system 11, the second-stage medium-pressure reverse osmosis membrane treatment system 17, and the third-stage high-pressure reverse osmosis membrane treatment system 23, both the nanofiltration membrane and the reverse osmosis membrane are spiral wound membranes, and the membrane modules are spiral wound membrane elements. In the fourth-stage ultra-high-pressure reverse osmosis membrane treatment system 29, the reverse osmosis membrane is a disc-type reverse osmosis membrane, and the membrane module is a disc-type membrane element.

[0036] This invention also includes an electrical control cabinet 36, which is used to control the manual and fully automatic operation of the integrated membrane separation enrichment and concentration device.

[0037] In this utility model, the electrical control cabinet 36 has a display screen 37, an automatic button 38, a manual button 39, and an emergency stop button 40;

[0038] The electrical control cabinet 36 has a built-in PLC controller 41, an IoT card 42, and a mobile APP control module 43.

[0039] Display screen 37 shows the entire process flow of the integrated membrane separation enrichment and concentration unit, system alarm information query, fault elimination, manual start / stop of individual equipment, and automatic start / stop of the entire unit. Pressing the automatic button 38 activates the entire unit automatically according to the set program. Pressing the manual button 39 puts the system in manual operation mode, allowing equipment debugging and troubleshooting personnel to manually start and stop each electrical device via the display screen 37. Pressing the emergency stop button 40 de-energizes all equipment outputs, stopping the electrical equipment. The equipment returns to manual or automatic control only when the emergency stop button is released. The PLC controller 41 can input control programs via an external line to control the entire unit. The IoT card 42 transmits equipment signal information to mobile terminals and the central control room terminal via IoT. The mobile APP control module 43 uses the IoT card to link equipment control with the mobile APP, enabling remote, real-time monitoring and start / stop of equipment control and mobile phone supervision.

[0040] This utility model also includes:

[0041] The membrane cleaning agent tank 32 is used to clean the integrated membrane separation, enrichment and concentration device.

[0042] This invention provides the concentration process of the above-mentioned integrated membrane separation enrichment and concentration device for short-process ionic rare earth elements, as detailed below:

[0043] (I) Integrated membrane separation and concentration process of rare earth leaching mother liquor

[0044] (1) The rare earth leaching solution collected from the in-situ leaching of rare earth mines is pretreated to obtain rare earth mother liquor 0, which flows into nanofiltration transfer tank 1. Nanofiltration transfer tank 1 is connected to a low-pressure nanofiltration pump 3. The nanofiltration pump 3 is equipped with a first electric three-way valve at its rear end. The nanofiltration transfer tank 1 is equipped with a first level gauge 2, which has three levels: high, medium, and low. When the level of nanofiltration transfer tank 1 is higher than the medium level, nanofiltration pump 3 is started to pump the rare earth mother liquor 0 into nanofiltration membrane treatment system 5. Preferably, a nanofiltration membrane with a molecular weight cutoff of 100-200 is selected, which can retain divalent or higher rare earth ions (all with molecular weights exceeding 100) in the rare earth mother liquor 0, while monovalent salts can pass through, thereby removing the monovalent salts in the rare earth mother liquor 0; a rare earth mother liquor 0 with a higher concentration is obtained and temporarily stored in the first-stage reverse osmosis transfer tank 7; the nanofiltration membrane permeate is returned to the leaching agent preparation.

[0045] (2) The rare earth solution temporarily stored in the primary reverse osmosis transfer tank 7 is connected to the low-pressure primary reverse osmosis pump 9. The primary reverse osmosis transfer tank 7 is equipped with a second level gauge 8, which has three levels: high, medium, and low. When the level in the primary reverse osmosis transfer tank 7 is higher than the medium level, the primary reverse osmosis pump 9 starts and pumps the rare earth solution into the primary low-pressure reverse osmosis membrane treatment system 11. The reverse osmosis membrane in the primary low-pressure reverse osmosis membrane treatment system 11 is a low-pressure reverse osmosis membrane element, suitable for rare earth concentrations less than 0.5 g / L, and an operating pressure of 0.2-1.2 MPa. The primary rare earth concentrate produced by filtration through the primary low-pressure reverse osmosis membrane treatment system 11 enters the secondary reverse osmosis transfer tank 13; the permeate from the primary low-pressure reverse osmosis membrane treatment system 11 is returned to the preparation of the leaching agent.

[0046] (3) The primary rare earth concentrate temporarily stored in the secondary reverse osmosis transfer tank 13 is connected to the medium-pressure secondary reverse osmosis pump 15. The secondary reverse osmosis transfer tank 13 is equipped with a third level gauge 14, which has three levels: high, medium, and low. When the level in the secondary reverse osmosis transfer tank 13 is higher than the medium level, the secondary reverse osmosis pump 15 starts and pumps the primary rare earth concentrate into the secondary medium-pressure reverse osmosis membrane treatment system 17. The reverse osmosis membrane in the secondary medium-pressure reverse osmosis membrane treatment system 17 is a medium-pressure reverse osmosis membrane element, suitable for rare earth concentrations less than 1.2 g / L, and an operating pressure of 1.0-1.6 MPa. The rare earth concentrate produced by filtration through the secondary medium-pressure reverse osmosis membrane treatment system 17 enters the tertiary reverse osmosis transfer tank 19; the permeate from the secondary medium-pressure reverse osmosis membrane treatment system 17 is returned to the primary reverse osmosis transfer tank 7.

[0047] (4) The secondary rare earth concentrate temporarily stored in the tertiary reverse osmosis transfer tank 19 is connected to the high-pressure tertiary reverse osmosis pump 21. The tertiary reverse osmosis transfer tank 19 is equipped with a fourth level gauge 20, which has three levels: high, medium, and low. When the level is higher than the medium level, the high-pressure tertiary reverse osmosis pump 21 starts and pumps the secondary rare earth concentrate into the tertiary high-pressure reverse osmosis membrane treatment system 23. The reverse osmosis membrane in the tertiary high-pressure reverse osmosis membrane treatment system 23 is a seawater desalination type reverse osmosis membrane element, suitable for rare earth concentrations less than 2.4 g / L, and an operating pressure of 1.5-2.5 MPa. The rare earth concentrate produced by filtration through the tertiary high-pressure reverse osmosis membrane treatment system 23 enters the tertiary reverse osmosis transfer tank 25; the permeate from the tertiary high-pressure reverse osmosis membrane treatment system 23 is returned to the pre-secondary reverse osmosis transfer tank 13.

[0048] (5) The third-stage rare earth concentrate temporarily stored in the fourth-stage reverse osmosis transfer tank 25 is connected to the ultra-high pressure fourth-stage reverse osmosis pump 27. The fourth-stage reverse osmosis transfer tank 25 is equipped with a fifth level gauge 26, which has three levels: high, medium and low. When the level is higher than the medium level, the ultra-high pressure fourth-stage reverse osmosis pump 27 starts and pumps the third-stage rare earth concentrate into the fourth-stage ultra-high pressure reverse osmosis membrane treatment system 29. The reverse osmosis membrane in the fourth-stage ultra-high pressure reverse osmosis membrane treatment system 29 is a disc-type high-pressure reverse osmosis membrane element, which is suitable for rare earth concentrations of less than 4 g / l and operating pressures of 4.0-7.5 MPa. The retentate produced by the four-stage ultra-high pressure reverse osmosis membrane treatment system 29 is returned to the four-stage reverse osmosis transfer tank 25. When the rare earth concentration in the tank reaches the set value, the rare earth concentrate discharge valve 31 at the bottom of the transfer tank is opened and discharged into the rare earth extraction system. The permeate from the four-stage ultra-high pressure reverse osmosis membrane treatment system 29 is returned to the three-stage reverse osmosis transfer tank 19.

[0049] (II) Electrical control system of integrated membrane separation and concentration device for rare earth leaching mother liquor

[0050] (1) The integrated membrane separation and concentration device for short-process mining-benefiting-smelting of ion-type rare earth adopts two operating modes: manual and fully automatic control. The selection is made by the automatic button 38 and the manual button 39 on the panel of the electrical control cabinet 36. In case of emergency, the power can be cut off by pressing the emergency stop button 40 on the panel.

[0051] (2) When the electrical control cabinet 36 is switched to manual operation mode: it can start and stop each electrical device and electric valve individually; it can also be used for the commissioning of the whole set of equipment; it can also be used to clean each membrane separation system individually: after the mode is switched to the cleaning module through the display screen 37 (preferably the touch screen), the touch screen adjusts the three-way electric valve on each membrane treatment system to the cleaning agent inlet, then opens the eleventh electric three-way ball valve 33 of the cleaning agent, closes the corresponding inlet valve, and the cleaning pump pushes the cleaning agent in the cleaning agent tank through the membrane cleaning pump 34 at a large flow rate and low pressure across the nanofiltration or reverse osmosis membrane surface. The cleaned cleaning agent is returned to the cleaning agent tank through the membrane cleaning agent return pipeline 35, thereby realizing the online cleaning of the nanofiltration or reverse osmosis membrane to reduce membrane fouling.

[0052] (3) When the electrical control cabinet 36 is set to the automatic button 38, the entire device will start automatically. The operation process is as follows:

[0053] 1) When the liquid level in the fourth-stage reverse osmosis transfer tank 25 is lower than the maximum liquid level, the equipment starts operating one by one; when the liquid level reaches the maximum liquid level, all the preceding equipment stops operating, and after a 10-second delay, the rare earth concentrate discharge valve 31 is opened to discharge the concentrated rare earth into the extraction unit. When the liquid level drops to the minimum liquid level, the rare earth concentrate discharge valve 31 is closed first, and the nanofiltration, first-stage, second-stage, third-stage, and fourth-stage reverse osmosis membrane treatment systems are restarted one by one, repeating the cycle.

[0054] 2) Nanofiltration System Control: When the liquid level in nanofiltration transfer tank 1 is below the maximum level, the inlet valve of rare earth mother liquor 0 opens, and the leaching mother liquor flows into nanofiltration transfer tank 1, causing the liquid level to rise. When the liquid level reaches the middle level, nanofiltration pump 3 starts, and the rare earth leaching mother liquor in the transfer tank is pumped into nanofiltration membrane treatment system 5. The membrane permeate returns to the leaching agent preparation, and the nanofiltration membrane concentrate flows into the first-stage reverse osmosis membrane transfer tank. The leaching mother liquor continues to flow into nanofiltration transfer tank 1. When the liquid level in the tank reaches the maximum level, the inlet valve of rare earth mother liquor 0 closes, and the liquid in the tank is divided into two streams by the nanofiltration membrane: one stream returns to the leaching agent preparation, and the other flows into the next-stage reverse osmosis membrane treatment system. If the liquid level in the tank reaches the minimum level, nanofiltration pump 3 stops operating to protect the equipment.

[0055] 3) First-stage reverse osmosis control: The nanofiltration membrane retentate flows into the first-stage reverse osmosis transfer tank 7, and the liquid level begins to rise. When it reaches the middle level, the first-stage reverse osmosis pump 9 starts, and the rare earth concentrate in the first-stage reverse osmosis transfer tank 7 is pumped into the first-stage low-pressure reverse osmosis membrane treatment system 11. The membrane permeate is returned to the leaching agent preparation, and the first-stage reverse osmosis concentrate flows into the second-stage reverse osmosis membrane transfer tank. When the liquid level in the first-stage reverse osmosis transfer tank 7 reaches the maximum level, the upstream nanofiltration stops operating until the liquid level drops below the middle level. If the liquid level in the tank reaches the minimum level, the first-stage reverse osmosis pump 9 stops operating to protect the equipment.

[0056] 4) Secondary Reverse Osmosis Control: The primary reverse osmosis membrane retentate flows into the secondary reverse osmosis transfer tank 13, and the liquid level begins to rise. When it reaches the middle level, the secondary reverse osmosis pump 15 starts, and the rare earth concentrate in the secondary reverse osmosis transfer tank 13 is pumped into the secondary medium-pressure reverse osmosis membrane system. The permeate returns to the primary reverse osmosis transfer tank 7, and the secondary reverse osmosis concentrate flows into the tertiary reverse osmosis membrane transfer tank. When the liquid level in the secondary reverse osmosis transfer tank 13 reaches the maximum level, the primary reverse osmosis transfer tank 7 stops operating until the liquid level drops below the middle level. If the liquid level in the tank reaches the minimum level, the secondary reverse osmosis pump 15 stops operating to protect the equipment.

[0057] 5) Three-stage reverse osmosis control: The retentate from the second-stage reverse osmosis membrane flows into the third-stage reverse osmosis transfer tank 19, and the liquid level begins to rise. When it reaches the middle level, the third-stage reverse osmosis pump 21 starts, and the rare earth concentrate in the third-stage reverse osmosis transfer tank 19 is pumped into the third-stage high-pressure reverse osmosis membrane treatment system 23. The permeate returns to the second-stage reverse osmosis transfer tank 13, and the third-stage reverse osmosis concentrate flows into the fourth-stage reverse osmosis membrane transfer tank. When the liquid level in the third-stage reverse osmosis transfer tank 19 reaches the highest level, the upstream second-stage reverse osmosis transfer tank 13 stops operating until the liquid level drops below the middle level. If the liquid level in the tank reaches the lowest level, the third-stage reverse osmosis pump 21 stops operating to protect the equipment.

[0058] 6) Four-stage reverse osmosis control: The retentate from the third-stage reverse osmosis membrane flows into the fourth-stage reverse osmosis transfer tank 25, and the liquid level begins to rise. When it reaches the middle level, the fourth-stage reverse osmosis pump 27 starts, and the rare earth concentrate in the fourth-stage reverse osmosis transfer tank 25 is pumped into the fourth-stage ultra-high pressure reverse osmosis membrane treatment system 29. The permeate returns to the third-stage reverse osmosis transfer tank 19, and the fourth-stage reverse osmosis concentrate returns to the fourth-stage reverse osmosis membrane transfer tank. As the concentrate from the upstream membrane system accumulates in the fourth-stage reverse osmosis transfer tank 25, the liquid level begins to rise. When it reaches the highest level, the upstream nanofiltration, first-stage, second-stage, and third-stage reverse osmosis transfer tank 19 stops operating. The rare earth concentrate discharge valve 31 is opened until the liquid level drops to the lowest level, and then the rare earth concentrate discharge valve 31 is closed. The upstream nanofiltration, first-stage, second-stage, third-stage, and fourth-stage reverse osmosis systems restart and operate in a continuous cycle.

[0059] (4) The electrical control cabinet 36 of the ion-type rare earth mining-benefiting-smelting short-process membrane concentration device has a built-in PLC controller 41, IoT card 42 (preferably 5G IoT card 42) and mobile APP control module 43. It can realize the device's equipment debugging, start and stop of single-stage membrane (nanofiltration, first-stage, second-stage, third-stage and fourth-stage reverse osmosis membrane) separation system, remote start and stop of the whole set of equipment, fault alarm query, fault elimination, real-time monitoring of equipment operation status, and transfer of rare earth concentrate, etc. through the mobile APP.

[0060] (5) Each stage of reverse osmosis pump is equipped with a low-pressure protection switch a and a high-pressure protection switch b. A pressure transmitter can also be installed. If the pressure before the reverse osmosis pump is lower than the set pressure (minimum pressure), the low-pressure protection switch a will be activated and the reverse osmosis pump will stop running. Once the pressure after the reverse osmosis pump exceeds the set pressure (maximum pressure), the high-pressure protection switch b will be activated and the reverse osmosis pump will stop running.

[0061] (6) The fluid flow direction and valve opening and closing of each membrane separation system are controlled by the electrical control cabinet 36, which opens and closes the valves and selects the fluid flow direction.

[0062] The electric valves mentioned in the above operation process refer to the first electric three-way ball valve 4 to the eleventh electric three-way ball valve 33. "Single membrane" refers to the nanofiltration membrane treatment system 5, the first-stage low-pressure reverse osmosis membrane treatment system 11, the second-stage medium-pressure reverse osmosis membrane treatment system 17, and the fourth-stage ultra-high-pressure reverse osmosis membrane treatment system 29.

[0063] On the other hand, this invention also provides an ionic rare earth short-process preparation system, including the above-mentioned integrated membrane separation, enrichment, and concentration device for ionic rare earth short-process preparation, which can be combined with an extraction system to form an ionic rare earth short-process preparation system. The above-mentioned ionic rare earth short-process preparation system of this invention will be described in detail below with reference to specific embodiments.

[0064] Example 1

[0065] The rare earth leaching mother liquor of 0.22 g / L was separated by nanofiltration at 0.4-0.8 MPa, resulting in a rare earth concentration of 0.30 g / L. After concentration in a primary low-pressure reverse osmosis membrane treatment system 11 at 1-1.6 MPa, the rare earth concentration was concentrated to 0.95 g / L. After concentration in a secondary medium-pressure reverse osmosis membrane treatment system 17 at 1.5-2.5 MPa, the rare earth concentration was concentrated to 2.36 g / L. After concentration in a tertiary high-pressure reverse osmosis membrane treatment system 23 at 2.0-4.5 MPa, the rare earth concentration was concentrated to 5.24 g / L. After concentration in a quaternary ultra-high-pressure reverse osmosis membrane treatment system 29 at 4.0-7.5 MPa, the rare earth concentration was concentrated to 12.31 g / L. After extraction with an extractant, the rare earth concentration in the back-extract reached 125 g / L.

[0066] Example 2

[0067] The rare earth leaching mother liquor with a concentration of 0.18 g / L was separated by nanofiltration at 0.4-0.8 MPa, resulting in a rare earth concentration of 0.27 g / L. After concentration in a primary low-pressure reverse osmosis membrane treatment system 11 at 1-1.6 MPa, the rare earth concentration was concentrated to 1.05 g / L. After concentration in a secondary medium-pressure reverse osmosis membrane treatment system 17 at 1.5-2.5 MPa, the rare earth concentration was concentrated to 2.25 g / L. After concentration in a tertiary high-pressure reverse osmosis membrane treatment system 23 at 2.0-4.5 MPa, the rare earth concentration was concentrated to 4.62 g / L. After concentration in a quaternary ultra-high-pressure reverse osmosis membrane treatment system 29 at 4.0-7.5 MPa, the rare earth concentration was concentrated to 11.05 g / L. After extraction with an extractant, the rare earth concentration in the back-extract reached 105 g / L.

[0068] Example 3

[0069] The rare earth leaching mother liquor with a concentration of 0.12 g / L was separated by nanofiltration at 0.4-0.8 MPa, resulting in a rare earth concentration of 0.21 g / L. After concentration in a primary low-pressure reverse osmosis membrane treatment system 11 at 1-1.6 MPa, the rare earth concentration was concentrated to 1.14 g / L. After concentration in a secondary medium-pressure reverse osmosis membrane treatment system 17 at 1.5-2.5 MPa, the rare earth concentration was concentrated to 2.12 g / L. After concentration in a tertiary high-pressure reverse osmosis membrane treatment system 23 at 2.0-4.5 MPa, the rare earth concentration was concentrated to 4.37 g / L. After concentration in a quaternary ultra-high-pressure reverse osmosis membrane treatment system at 6.0-7.5 MPa, the rare earth concentration was concentrated to 11.09 g / L. After extraction with an extractant, the rare earth concentration in the back-extract reached 116 g / L.

[0070] The above are merely preferred embodiments of this utility model; however, the scope of protection of this utility model is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in this utility model, based on the technical solution and its improved concept, should be included within the scope of protection of this utility model.

Claims

1. An integrated membrane separation, enrichment, and concentration device for short-process ion-type rare earth elements, characterized in that, It includes a nanofiltration transfer tank, a nanofiltration membrane treatment system, a first-stage reverse osmosis transfer tank, a first-stage low-pressure reverse osmosis membrane treatment system, a second-stage reverse osmosis transfer tank, a second-stage medium-pressure reverse osmosis membrane treatment system, a third-stage reverse osmosis transfer tank, a third-stage high-pressure reverse osmosis membrane treatment system, a fourth-stage reverse osmosis transfer tank, and a fourth-stage ultra-high-pressure reverse osmosis membrane treatment system, all connected in sequence. The nanofiltration transfer tank and the nanofiltration membrane treatment system, the first-stage reverse osmosis transfer tank and the first-stage low-pressure reverse osmosis membrane treatment system, the second-stage reverse osmosis transfer tank and the second-stage medium-pressure reverse osmosis membrane treatment system, the third-stage reverse osmosis transfer tank and the third-stage high-pressure reverse osmosis membrane treatment system, and the fourth-stage reverse osmosis transfer tank and the fourth-stage ultra-high-pressure reverse osmosis membrane treatment system are all driven by pumps, and each is equipped with a low-pressure protection switch and a high-pressure protection switch.

2. The integrated membrane separation, enrichment, and concentration device for short-process ion-type rare earth elements according to claim 1, characterized in that, It also includes an electrical control cabinet, which is used to control the manual and fully automatic operation of the integrated membrane separation enrichment and concentration device.

3. The integrated membrane separation, enrichment, and concentration device for short-process ion-type rare earth elements according to claim 2, characterized in that, The electrical control cabinet is equipped with a display screen, automatic buttons, manual buttons, and an emergency stop button; The electrical control cabinet has a built-in PLC controller, IoT card, and mobile APP control module.

4. The integrated membrane separation, enrichment, and concentration device for short-process ion-type rare earth elements according to claim 1, characterized in that, Also includes: A membrane cleaning agent tank is used to clean the integrated membrane separation, enrichment, and concentration device.

5. The integrated membrane separation, enrichment, and concentration device for short-process ion-type rare earth elements according to claim 1, characterized in that, Each of the nanofiltration transfer tank, the first-stage reverse osmosis transfer tank, the second-stage reverse osmosis transfer tank, the third-stage reverse osmosis transfer tank, and the fourth-stage reverse osmosis transfer tank is equipped with a level gauge.

6. The integrated membrane separation, enrichment, and concentration device for short-process ion-type rare earth elements according to claim 5, characterized in that, The level gauge is a magnetic float level gauge.

7. The integrated membrane separation, enrichment, and concentration device for short-process ion-type rare earth elements according to claim 1, characterized in that, The nanofiltration membrane treatment system, the first-stage low-pressure reverse osmosis membrane treatment system, the second-stage medium-pressure reverse osmosis membrane treatment system, the third-stage high-pressure reverse osmosis membrane treatment system, and the fourth-stage ultra-high-pressure reverse osmosis membrane treatment system are respectively nanofiltration membrane stack, first-stage reverse osmosis membrane stack, second-stage reverse osmosis membrane stack, third-stage reverse osmosis membrane stack, and fourth-stage reverse osmosis membrane stack.

8. A short-process preparation system for ionic rare earth elements, characterized in that, The invention includes an integrated membrane separation enrichment and concentration device for short-process ion-type rare earth as described in any one of claims 1-7.

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