Circulation structure for two-stage temperature control deoxalate of sodium aluminate solution

Abstract

The present application relates to the technical field of sodium aluminate solution, and provides a circulating structure for two-stage temperature control and oxalate removal of sodium aluminate solution, which comprises a bottom plate, a conveying pump is fixedly connected to the top of the bottom plate, a plate heat exchanger is fixedly connected to the top of the bottom plate, a solution input pipe and a cooling liquid input pipe are in communication with the side of the plate heat exchanger, a settling tank is fixedly connected to the top of the bottom plate, and a stable settling structure is arranged in the settling tank. The stable settling structure comprises a fixed plate, the bottom of the fixed plate is fixedly connected to the top of the settling tank, a speed reducer is fixedly connected to the top of the fixed plate, and a motor is fixedly connected to the side of the speed reducer. The circulating structure for two-stage temperature control and oxalate removal of sodium aluminate solution provided by the present application can make oxalate crystals effectively agglomerate and grow in a relatively static environment through flexible stirring of the stable settling structure, so as to promote mutual contact, agglomeration and gradual settling of fine grains.

Description

Technical Field

[0001] This invention relates to the field of sodium aluminate solution technology, and more specifically to a two-stage temperature-controlled cyclic structure for deoxatate removal from sodium aluminate solution. Background Technology

[0002] In the Bayer process for alumina production, sodium aluminate solution is the core process medium. As bauxite is leached and the mother liquor is repeatedly used, organic matter (mainly humic acids) in the ore gradually dissolves and accumulates in the sodium aluminate solution. Under high temperature and high alkalinity conditions, these organic substances decompose, eventually forming oxalate impurities, mainly sodium oxalate.

[0003] According to the published sodium aluminate solution heat exchanger (publication number: CN212538907U), it includes a heat exchanger body. An air inlet pipe is threaded into the middle of the upper surface of the heat exchanger body near both ends. An air outlet pipe is threaded into both sides of the middle of the lower surface of the heat exchanger body. A feed pipe is fixedly connected inside the heat exchanger body by screws. This utility model creates an air passage between the heat exchanger body and the feed pipe by incorporating a cylindrical feed pipe inside the heat exchanger body. This allows the user to input external hot steam into the heat exchanger body through the air inlet pipe and then transport the heat-exchanged hot steam to the outside through the air outlet pipe, achieving a circulating heating effect. This allows the sodium aluminate solution transported in the feed pipe to be effectively heated. Furthermore, by reducing the diameter of the feed pipe, multiple feed pipes can be added within the original volume of the heat exchanger body, and the reduced diameter reduces the heating thickness of the solution, thus enabling better heating of the solution.

[0004] In the aforementioned application, although the sodium aluminate solution can be heated by the heat exchanger body, it does not have corresponding temperature control and anti-deposition measures for the oxalate crystallization process. When the solution cools down, scale easily adheres to the inner wall of the equipment, affecting the heat exchange efficiency and continuous operation. Therefore, we propose a two-stage temperature-controlled circulatory structure for deoxalate removal from sodium aluminate solution. Summary of the Invention

[0005] To overcome the above-mentioned defects, embodiments of the present invention provide a two-stage temperature-controlled oxalate removal circulation structure for sodium aluminate solution, which solves the technical problems affecting heat exchange efficiency and operational continuity in related technologies.

[0006] At least one embodiment of the present invention provides a two-stage temperature-controlled oxalate removal circulation structure for sodium aluminate solution, including a base plate, a delivery pump fixedly connected to the top of the base plate, a plate heat exchanger fixedly connected to the top of the base plate, a solution inlet pipe and a coolant inlet pipe connected to the side of the plate heat exchanger, and a settling tank fixedly connected to the top of the base plate, wherein a stable settling structure is provided inside the settling tank.

[0007] The stabilizing settling structure includes a fixed plate, the bottom of which is fixedly connected to the top of the settling tank. A reducer is fixedly connected to the top of the fixed plate, a motor is fixedly connected to the side of the reducer, and a drive shaft is fixedly connected to the output shaft of the reducer. A retaining ring a is fixedly connected to the circumferential surface of the drive shaft. An agitator is fixedly connected to the inner wall of the retaining ring a. A wing plate is rotatably connected to the side of the agitator. A side plate is fixedly connected to the top of the agitator. A connecting block is fixedly connected to the side of the agitator. A retainer is fixedly connected to the circumferential surface of the drive shaft, and a slider is fixedly connected to the side of the connecting block.

[0008] According to one embodiment of this application, the output shaft of the motor is fixedly connected to the input shaft of the reducer, and the solution outlet of the plate heat exchanger is connected to the inlet of the delivery pump. This achieves stable power transmission and stable pipeline connectivity.

[0009] According to one embodiment of this application, the slider has an arc-shaped side and is slidably connected to the inner wall of the retainer. The output port of the delivery pump is connected to the top of the settling tank via a connecting pipe. This allows the agitator to rotate more smoothly, reducing jamming and also scraping away scale in the rotating groove. The delivery pump output port is connected to the top of the settling tank via a connecting pipe, allowing the solution to enter from the top and facilitating uniform distribution within the tank.

[0010] According to one embodiment of this application, the number of fixing plates is several, and they are distributed in a circumferential array along the top of the settling tank. This ensures that the reducer and motor are securely installed and the force is evenly distributed.

[0011] According to one embodiment of this application, the circumferential surface of the drive shaft is provided with an anti-settling and cleaning structure. The anti-settling and cleaning structure includes a fixing frame, the side of the fixing frame is fixedly connected to the circumferential surface of the drive shaft, a scraper is fixedly connected to the side of the fixing frame, a mounting plate is fixedly connected to the bottom of the fixing frame, a rake tooth is fixedly connected to the bottom of the mounting plate, a scraper is fixedly connected to the side of the mounting plate, a sealing frame is fixedly connected to the top of the mounting plate, a sealing column is slidably connected to the side of the sealing frame, a spring is provided on the inner wall of the sealing column, and a wall removal plate is fixed to the end of the sealing column away from the sealing frame.

[0012] According to one embodiment of this application, the scraper is located behind the rake teeth. This allows the rake teeth to loosen the deposits first, followed by the scraper removing them, creating a sequential cleaning process and improving cleaning efficiency.

[0013] According to one embodiment of this application, one end of the spring abuts against the wall scraping plate, and the other end abuts against the side of the sealing frame. This provides a continuous elastic thrust to the wall scraping plate, allowing it to adapt to changes in the tank wall shape and maintain a stable wall scraping effect.

[0014] According to one embodiment of this application, the settling tank is provided with a two-stage temperature control circulation structure. The two-stage temperature control circulation structure includes a circulation pump. The top of the circulation pump is fixedly connected to the bottom of the settling tank, and a circulation pipe is fixedly connected to the bottom of the circulation pump. A first cooling plate, a second cooling plate, and a third cooling plate are fixedly connected from top to bottom on the inner side wall of the settling tank. An overflow pipe is connected to the sides of the first cooling plate, the second cooling plate, and the third cooling plate.

[0015] According to one embodiment of this application, there are multiple overflow pipes arranged in a circumferential array on the circumferential surface of the settling tank, and the first cooling plate has a concave structure. This ensures uniform overflow of the solution from each cooling plate, reducing flow deviation. The concave structure of the first cooling plate facilitates the solution's convergence towards the center and its orderly entry into the next stage, and also provides space for the installation of the drive shaft.

[0016] According to one embodiment of this application, the wall-mounted scraper is located on the movement trajectory of the inner sidewall of the first cooling plate, and the rake teeth are located on the movement trajectory of the inner bottom wall of the first cooling plate. This directly removes scale deposits adhering to this area, maintaining the heat exchange capacity of the cooling plate and the flowability of the solution.

[0017] The present invention provides a two-stage temperature-controlled cyclic structure for deoxatate removal from sodium aluminate solution. Compared with the prior art, the flexible stirring of the stable sedimentation structure enables oxalate crystals to effectively agglomerate and grow in a relatively static environment, promoting the contact, agglomeration, and gradual sedimentation of fine crystals.

[0018] The present invention provides a two-stage temperature-controlled oxalate removal circulation structure for sodium aluminate solution, while the anti-precipitation and cleaning structure continuously cleans the tank wall and bottom, slows down scale accumulation, and extends the cleaning cycle.

[0019] The present invention provides a two-stage temperature-controlled cyclic structure for deoxatate removal from sodium aluminate solution. The two-stage temperature-controlled cyclic structure provides a gentle cooling environment, which allows the crystallization process to proceed in an orderly manner. This is beneficial for obtaining oxalate crystals with a concentrated particle size distribution that are easy to separate, and reduces the burden on subsequent processes. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1This is a structural schematic diagram of the overall three-dimensional appearance provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of the internal structure of the settling tank provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of the stable settlement structure provided in an embodiment of the present invention; Figure 4 Provided by the embodiments of the present invention Figure 3 A three-dimensional magnified structural diagram of A in the diagram; Figure 5 This is a schematic diagram of the anti-precipitation and removal structure provided in an embodiment of the present invention; Figure 6 Provided by the embodiments of the present invention Figure 5 A three-dimensional magnified structural diagram of B; Figure 7 This is a schematic diagram of the two-stage temperature control circulation structure provided in an embodiment of the present invention; In the diagram: 1. Base plate; 2. Transfer pump; 3. Plate heat exchanger; 4. Solution inlet pipe; 5. Coolant inlet pipe; 6. Settling tank; 7. Stabilizing settling structure; 701. Fixed plate; 702. Reducer; 703. Motor; 704. Drive shaft; 704a. Snap ring; 705. Agitator; 706. Wing plate; 707. Side plate; 708. Connecting block; 709. Cage; 710. Sliding block; 8. Anti-sedimentation removal structure; 801, fixing frame; 802, scraper; 803, mounting plate; 804, rake teeth; 805, scraper blade; 806, sealing frame; 807, sealing column; 808, spring; 809, wall removal plate; 9, two-stage temperature control circulation structure; 901, circulation pump; 902, circulation pipe; 903, first cooling plate; 904, second cooling plate; 905, third cooling plate; 906, overflow pipe. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below with reference to the accompanying drawings. In the drawings, the same or similar reference numerals denote the same or similar components or components having the same or similar functions throughout. The described embodiments are some, but not all, embodiments of this application. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0023] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, an indirect connection through an intermediate medium, or the internal communication between two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0024] In the description of this application, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application 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. Therefore, they should not be construed as limitations on this application.

[0025] The terms "first," "second," "third," "fourth," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented, for example, in a sequence other than those illustrated or described herein.

[0026] To make the drawings concise and easy to understand, some drawings only show one of the components with the same structure or function, or only one of them is marked. In this article, "one" not only means "only one", but can also mean "more than one", and "several" includes "two" and "more than two".

[0027] Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not necessarily limited to those explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus. It is understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. The embodiments of this application are described in detail below with reference to the accompanying drawings.

[0028] like Figures 1-7 As shown, it illustrates a two-stage temperature-controlled deoxatate circulation structure for sodium aluminate solution in an embodiment of the present invention, including a base plate 1, a transfer pump 2 fixedly connected to the top of the base plate 1, a plate heat exchanger 3 fixedly connected to the top of the base plate 1, a solution inlet pipe 4 and a coolant inlet pipe 5 connected to the side of the plate heat exchanger 3, a settling tank 6 fixedly connected to the top of the base plate 1, and a stabilizing settling structure 7 provided inside the settling tank 6.

[0029] The stabilizing settling structure 7 includes a fixed plate 701, the bottom of which is fixedly connected to the top of the settling tank 6. A reducer 702 is fixedly connected to the top of the fixed plate 701. A motor 703 is fixedly connected to the side of the reducer 702. A drive shaft 704 is fixedly connected to the output shaft of the reducer 702. A retaining ring 704a is fixedly connected to the circumferential surface of the drive shaft 704. An agitator 705 is fixedly connected to the inner wall of the retaining ring 704a. A wing plate 706 is rotatably connected to the side of the agitator 705. A side plate 707 is fixedly connected to the top of the agitator 705. A connecting block 708 is fixedly connected to the side of the agitator 705. A retainer 709 is fixedly connected to the circumferential surface of the drive shaft 704. A slider 710 is fixedly connected to the side of the connecting block 708.

[0030] The output shaft of motor 703 is fixedly connected to the input shaft of reducer 702, and the solution outlet of plate heat exchanger 3 is connected to the inlet of transfer pump 2. This ensures stable power transmission and stable pipeline connection.

[0031] The slider 710 has an arc-shaped side and is slidably connected to the inner wall of the retainer 709. The output port of the transfer pump 2 is connected to the top of the settling tank 6 through a connecting pipe. This allows the agitator 705 to rotate more smoothly, reducing jamming, and can also scrape off scale in the rotating tank. The output port of the transfer pump 2 is connected to the top of the settling tank 6 through a connecting pipe, allowing the solution to enter from the top, which is beneficial for uniform distribution in the tank.

[0032] There are several fixing plates 701, which are arranged in a circumferential array along the top of the settling tank 6. This ensures that the reducer 702 and the motor 703 are securely installed and subjected to uniform force.

[0033] As a specific embodiment, the oxalate crystals are effectively agglomerated and grown in a relatively static environment by the flexible stirring of the stable sedimentation structure 7, which promotes the contact, agglomeration and gradual sedimentation of the fine grains.

[0034] In some embodiments, after the device is started, the motor 703 drives the transmission shaft 704 to rotate smoothly via the reducer 702, and the stable settling structure 7 begins to work. The transmission shaft 704 drives the agitator 705 to rotate via the retaining ring 704a. The wing plate 706 connected to the agitator 705 slowly moves across the solution, and its angle can be finely adjusted according to the resistance, thereby forming a gentle turbulent flow. This turbulence will not break the formed oxalate crystals, but will promote the contact, aggregation and gradual settling of fine crystals. At the same time, the connecting block 708 and the arc-shaped slider 710 fixed on its side slide on the inner wall of the retainer 709, which not only provides circumferential support for the agitator 705, but also scrapes off a small amount of scale that may precipitate on the mating surface during the sliding process, keeping the rotation smooth.

[0035] This embodiment provides a two-stage temperature-controlled oxalate removal circulation structure for sodium aluminate solution. A sedimentation removal structure 8 is provided on the circumferential surface of the drive shaft 704. The sedimentation removal structure 8 includes a fixing frame 801, with its side fixedly connected to the circumferential surface of the drive shaft 704. A scraper 802 is fixedly connected to the side of the fixing frame 801, and a mounting plate 803 is fixedly connected to the bottom of the fixing frame 801. A rake tooth 804 is fixedly connected to the bottom of the mounting plate 803, and a scraper blade 805 is fixedly connected to the side of the mounting plate 803. A sealing frame 806 is fixedly connected to the top of the mounting plate 803, and a sealing column 807 is slidably connected to the side of the sealing frame 806. A spring 808 is provided on the inner wall of the sealing column 807, and a wall removal plate 809 is fixed to the end of the sealing column 807 away from the sealing frame 806.

[0036] The scraper blade 805 is located behind the rake teeth 804. This allows the rake teeth 804 to loosen the sediment first, and then the scraper blade 805 to scrape it off, forming a sequential cleaning process and improving cleaning efficiency.

[0037] One end of the spring 808 abuts against the wall scraper 809, and the other end abuts against the side of the sealing frame 806. This provides a continuous elastic thrust to the wall scraper 809, allowing it to adapt to changes in the tank wall shape and maintain a stable scraping effect.

[0038] As a specific embodiment, the anti-sludge removal structure 8 continuously cleans the tank walls and bottom, slows down scale accumulation, and extends the cleaning cycle.

[0039] In some embodiments, the anti-settling and cleaning structure 8, which rotates synchronously with the drive shaft 704, is activated. The fixed frame 801 drives the scraper 802 to scrape along the tank wall, preventing crystals from adhering to the wall surface for a long time. The rake teeth 804 at the bottom of the mounting plate 803 loosen the sediment layer at the bottom of the tank, keeping the sediment in a loose state; the scraper 805 located behind the rake teeth 804 then pushes the loosened material forward to form an orderly sludge removal. The sealing frame 806 at the top of the mounting plate 803 contains a spring 808, which continuously pushes the sealing column 807 and the wall removal plate 809 fixed thereto, so that the wall removal plate 809 elastically fits the tank wall, adapting to the slight deformation caused by tank processing or heating, and stably scraping away the scale on the wall surface.

[0040] refer to Figures 1-7 In one possible implementation, the settling tank 6 is provided with a two-stage temperature control circulation structure 9. The two-stage temperature control circulation structure 9 includes a circulation pump 901. The top of the circulation pump 901 is fixedly connected to the bottom of the settling tank 6, and the bottom of the circulation pump 901 is fixedly connected to a circulation pipe 902. The inner sidewall of the settling tank 6 is fixedly connected from top to bottom to a first cooling plate 903, a second cooling plate 904, and a third cooling plate 905. The sides of the first cooling plate 903, the second cooling plate 904, and the third cooling plate 905 are all connected to an overflow pipe 906.

[0041] There are multiple overflow pipes 906, which are distributed in a circumferential array on the circumferential surface of the settling tank 6. The first cooling plate 903 has a concave structure. This ensures that the solution overflows evenly from each cooling plate and reduces flow deviation. The concave structure of the first cooling plate 903 facilitates the solution to converge towards the center and enter the next stage in an orderly manner, and also provides space for the installation position of the drive shaft 704.

[0042] The wall-mounted plate 809 is positioned on the movement trajectory of the inner wall of the first cooling plate 903, and the rake teeth 804 are positioned on the movement trajectory of the inner bottom wall of the first cooling plate 903. This allows for the direct removal of scale deposits in this area, maintaining the heat exchange capacity of the cooling plate and the flow of the solution.

[0043] As a specific embodiment, the two-stage temperature-controlled circulation structure 9, in conjunction with the above actions, provides a gentle cooling environment, allowing the crystallization process to proceed in an orderly manner. This is beneficial for obtaining oxalate crystals with concentrated particle size distribution and easy separation, thereby reducing the burden on subsequent processes.

[0044] Furthermore, simultaneously, the two-stage temperature-controlled circulation structure 9 begins operation. The circulation pump 901 continuously circulates and transports the solution in the tank through the circulation pipe 902. The solution flows from top to bottom through the first cooling plate 903, the second cooling plate 904, and the third cooling plate 905 in the settling tank 6. Each cooling plate utilizes evenly distributed overflow pipes 906 to achieve layer-by-layer overflow of the solution, resulting in a slow, stepped temperature decrease. This avoids explosive nucleation caused by excessively rapid cooling. The first cooling plate 903 has a concave structure, guiding the solution to converge towards the center and then uniformly enter the overflow pipe 906 before entering the next stage. This also leaves space for the arrangement of the drive shaft 704. The cleaning tracks of the wall removal plate 809 and the rake teeth 804 cover the inner side wall and bottom wall of the first cooling plate 903, respectively, which can promptly remove sediment in this area and maintain the heat exchange effect of the cooling plate and the flow of the solution.

[0045] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A two-stage temperature-controlled cyclic structure for deoxatate removal from sodium aluminate solution, characterized in that, Includes a base plate (1), a delivery pump (2) is fixedly connected to the top of the base plate (1), a plate heat exchanger (3) is fixedly connected to the top of the base plate (1), a solution input pipe (4) and a coolant input pipe (5) are connected to the side of the plate heat exchanger (3), a settling tank (6) is fixedly connected to the top of the base plate (1), and a stable settling structure (7) is provided inside the settling tank (6). The stabilizing settling structure (7) includes a fixed plate (701), the bottom of which is fixedly connected to the top of the settling tank (6). A reducer (702) is fixedly connected to the top of the fixed plate (701), and a motor (703) is fixedly connected to the side of the reducer (702). A drive shaft (704) is fixedly connected to the output shaft of the reducer (702), and a retaining ring (704a) is fixedly connected to the circumferential surface of the drive shaft (704). The inner wall of the snap ring (704a) is fixedly connected to an agitator (705), the side of the agitator (705) is rotatably connected to a wing plate (706), the top of the agitator (705) is fixedly connected to a side plate (707), the side of the agitator (705) is fixedly connected to a connecting block (708), the circumferential surface of the drive shaft (704) is fixedly connected to a retainer (709), and the side of the connecting block (708) is fixedly connected to a slider (710).

2. The circulating structure for two-stage temperature-controlled oxalate removal from sodium aluminate solution according to claim 1, characterized in that, The output shaft of the motor (703) is fixedly connected to the input shaft of the reducer (702), and the solution outlet of the plate heat exchanger (3) is connected to the input outlet of the transfer pump (2).

3. The circulating structure for two-stage temperature-controlled oxalate removal from sodium aluminate solution according to claim 2, characterized in that, The slider (710) has an arc-shaped side and is slidably connected to the inner wall of the retainer (709). The output port of the delivery pump (2) is connected to the top of the settling tank (6) through a connecting pipe.

4. The circulating structure for two-stage temperature-controlled oxalate removal from sodium aluminate solution according to claim 3, characterized in that, The number of fixed plates (701) is several, and they are arranged in a circular array along the top of the settling tank (6).

5. The circulating structure for two-stage temperature-controlled oxalate removal from sodium aluminate solution according to claim 4, characterized in that, The circumferential surface of the drive shaft (704) is provided with an anti-settling and cleaning structure (8). The anti-settling and cleaning structure (8) includes a fixing frame (801). The side of the fixing frame (801) is fixedly connected to the circumferential surface of the drive shaft (704). A scraper (802) is fixedly connected to the side of the fixing frame (801). A mounting plate (803) is fixedly connected to the bottom of the fixing frame (801). A rake tooth (804) is fixedly connected to the bottom of the mounting plate (803). A scraper (805) is fixedly connected to the side of the mounting plate (803). A sealing frame (806) is fixedly connected to the top of the mounting plate (803). A sealing column (807) is slidably connected to the side of the sealing frame (806). A spring (808) is provided on the inner wall of the sealing column (807). A wall removal plate (809) is fixed to the end of the sealing column (807) away from the sealing frame (806).

6. The circulating structure for two-stage temperature-controlled oxalate removal from sodium aluminate solution according to claim 5, characterized in that, The scraper (805) is located behind the rake teeth (804).

7. The circulating structure for two-stage temperature-controlled deoxatate removal from sodium aluminate solution according to claim 6, characterized in that, One end of the spring (808) abuts against the wall plate (809), and the other end abuts against the side of the sealing frame (806).

8. The circulating structure for two-stage temperature-controlled oxalate removal from sodium aluminate solution according to claim 7, characterized in that, The settling tank (6) is provided with a two-stage temperature control circulation structure (9). The two-stage temperature control circulation structure (9) includes a circulation pump (901). The top of the circulation pump (901) is fixedly connected to the bottom of the settling tank (6). The bottom of the circulation pump (901) is fixedly connected to a circulation pipe (902). The inner sidewall of the settling tank (6) is fixedly connected from top to bottom to a first cooling plate (903), a second cooling plate (904), and a third cooling plate (905). The sides of the first cooling plate (903), the second cooling plate (904), and the third cooling plate (905) are all connected to an overflow pipe (906).

9. The circulating structure for two-stage temperature-controlled oxalate removal from sodium aluminate solution according to claim 8, characterized in that, The number of overflow pipes (906) is multiple and they are distributed in a circumferential array on the circumferential surface of the settling tank (6). The first cooling plate (903) has a concave structure.

10. The circulating structure for two-stage temperature-controlled deoxatate removal from sodium aluminate solution according to claim 9, characterized in that, The wall removal plate (809) is located on the movement trajectory of the inner side wall of the first cooling plate (903), and the rake teeth (804) are located on the movement trajectory of the inner bottom wall of the first cooling plate (903).

Images