Aluminum oxide evaporation circulating water heat recovery device
By designing an alumina evaporation circulating water heat recovery device, and employing multi-layer filtration and flocculation technology to remove impurities from the circulating water, the problem of circulating water accumulation in equipment and pipelines was solved, thereby improving the heat energy circulation efficiency and the maintainability of the device.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- HEBEI WENFENG NEW MATERIAL CO LTD
- Filing Date
- 2025-05-16
- Publication Date
- 2026-04-17
AI Technical Summary
In the alumina evaporation process, as the circulating water flows through the equipment and pipes, impurities accumulate in dead corners, causing damage to the equipment and pipes and affecting the heat energy circulation effect.
A heat recovery device for circulating water in alumina evaporation is designed, comprising a shell, a filter screen, a quartz sand filter layer, and an activated carbon filter layer. Impurities are removed through multi-layer filtration, and the purification effect is improved by using flocculants and spiral guide plates. A backwashing system is combined to maintain the filter elements.
It effectively reduces the impurity content in circulating water, avoids clogging and wear, improves the waste heat utilization rate of high-temperature circulating water, extends equipment life and reduces maintenance costs.
Smart Images
Figure CN224132884U_ABST
Abstract
Description
Technical Field
[0001] The embodiments disclosed herein relate to the field of heat recovery device technology, and more specifically, to a heat recovery device for circulating water in alumina evaporation. Background Technology
[0002] Alumina has a wide range of applications in materials manufacturing, electronic and electrical components, and mechanical engineering, and the demand for it is increasing daily. However, alumina is produced from alumina ore through dozens of complex processes, which consume a lot of energy. Therefore, it is necessary to optimize the relevant processes for cost reduction and efficiency improvement in alumina production. The evaporation process is the most energy-intensive process in the entire Bayer process of alumina production, accounting for 20-25% of the total energy consumption. Therefore, optimizing the system operation path of the evaporation process and building an energy-saving evaporation system is of great significance for reducing the overall energy consumption cost of alumina production.
[0003] Currently, in the alumina evaporation process, the heating of the sodium aluminate solution evaporator often employs a fresh steam liquefaction heat exchange method. The condensate from the liquefied fresh steam carries a large amount of heat into a cooling tower, where it is cooled again through heat exchange before entering a settling hot water station. There, it is heated by a heating pump and then circulated into the settling tank for backwashing. However, the circulating water contains impurities such as ore particles, metal shavings, and silt. As it flows through various equipment and pipelines, these impurities accumulate in dead corners, easily causing damage through blockages, wear, and scaling, thus affecting the thermal energy circulation efficiency of the pipelines. Utility Model Content
[0004] To overcome the above-mentioned defects, the embodiments of this disclosure provide an alumina evaporation circulating water heat recovery device, which solves the technical problem in the related art where impurities accumulate in the dead corners of equipment and pipes when circulating water flows through various equipment and pipes, affecting the heat energy circulation effect of the pipes.
[0005] According to one aspect, at least one embodiment of this disclosure provides an alumina evaporation circulating water heat recovery device for connection to a settling hot water station, comprising:
[0006] The housing has a liquid inlet and a liquid outlet, the liquid inlet being used to communicate with the sedimentation hot water station;
[0007] A filter screen is disposed inside the housing, with the liquid inlet located on one side of the filter screen and the liquid outlet located on the other side of the filter screen;
[0008] A quartz sand filter layer is disposed inside the housing and located between the filter screen and the drain port;
[0009] An activated carbon filter layer is disposed inside the housing and located between the quartz sand filter layer and the drain outlet;
[0010] A settling tank, the inlet of which is connected to the drain outlet.
[0011] For example, in an alumina evaporation circulating water heat recovery device provided in at least one embodiment of this disclosure, the liquid inlet is located at the lower end of the side wall of the shell, the liquid outlet is located at the upper end of the side wall of the shell, and the filter screen, the quartz sand filter layer, and the activated carbon filter layer are arranged sequentially from bottom to top.
[0012] For example, in at least one embodiment of the alumina evaporation circulating water heat recovery device provided in this disclosure, the bottom of the shell is conical and has a slag discharge port, the slag discharge port being located at the lower end of the cone. The alumina evaporation circulating water heat recovery device further includes:
[0013] Support legs, the upper end of which is connected to the housing and used to support the housing; there are multiple support legs, and all the support legs are arranged around the slag discharge port.
[0014] A sealing element, which is detachably installed at the slag discharge port.
[0015] For example, in an alumina evaporation circulating water heat recovery device provided in at least one embodiment of this disclosure, the filter screen is detachably connected to the shell, the quartz sand filter layer is detachably connected to the shell, and the activated carbon filter layer is detachably connected to the shell.
[0016] For example, in at least one embodiment of this disclosure, an alumina evaporation circulating water heat recovery device further includes:
[0017] A transfer pump, which is connected between the drain outlet and the settling tank;
[0018] A drain pipe, which connects the delivery pump and the settling tank;
[0019] A flocculant dispensing pipe, the outlet end of which is connected to the drain pipe.
[0020] For example, in at least one embodiment of the present disclosure, an alumina evaporation circulating water heat recovery device is provided, which further includes a spiral guide plate. The spiral guide plate is disposed in the drain pipe to form a spiral channel in the drain pipe. The outlet end of the flocculant dosing pipe is connected to the end of the spiral channel near the delivery pump.
[0021] For example, in an alumina evaporation circulating water heat recovery device provided in at least one embodiment of this disclosure, the drain pipe is detachably connected to the delivery pump, and the drain pipe is detachably connected to the settling tank.
[0022] For example, in at least one embodiment of this disclosure, an alumina evaporation circulating water heat recovery device further includes:
[0023] A first flange is mounted on the delivery pump. The first flange has a first retaining ring on the side facing the drain pipe, and the first retaining ring is inserted into the drain pipe.
[0024] The second flange is located at the inlet of the settling tank. The second flange has a second retaining ring on the side facing the drain pipe. The second retaining ring is inserted into the drain pipe. The spiral guide plate is inserted into the drain pipe and clamped between the first retaining ring and the second retaining ring.
[0025] The third flange is provided at both ends of the drain pipe. The third flange is detachably connected to the first flange and the third flange is detachably connected to the second flange.
[0026] For example, in at least one embodiment of this disclosure, an alumina evaporation circulating water heat recovery device further includes:
[0027] A cover is disposed on the top of the housing, and the cover is detachably connected to the housing;
[0028] A backwash pipe, located on the outside of the cover;
[0029] A backwash nozzle is disposed on the cover, the inlet of the backwash nozzle is connected to the backwash pipe, and the outlet of the backwash nozzle faces the interior of the housing.
[0030] For example, in an alumina evaporation circulating water heat recovery device provided in at least one embodiment of this disclosure, the backwash nozzle is threadedly connected to the cover body, and the backwash nozzle is threadedly connected to the backwash pipe.
[0031] The beneficial effects of the embodiments disclosed herein are as follows: After the circulating water enters the shell through the inlet, it first passes through a filter screen for coarse filtration, removing rust and other metal slag and large particulate solid impurities generated by pipeline corrosion. Then, it passes through a quartz sand filter layer, where fine particles are screened out. When passing through an activated carbon filter layer, pigment molecules come into contact with the high specific surface area of the activated carbon and are retained under the adsorption of active functional groups, thus completing the adsorption and removal of fine particles and pigments in the circulating water. Finally, it is discharged through the drain outlet into the settling tank. This effectively reduces the impurity content in the circulating water, preventing impurities from accumulating in dead corners of equipment and pipelines, avoiding damage to equipment and pipelines caused by blockages, wear, and scaling, reducing the impact on the thermal energy circulation effect of the pipelines, and improving the waste heat utilization rate of high-temperature circulating water. Attached Figure Description
[0032] To more clearly illustrate the technical solutions in the embodiments of this disclosure, the accompanying drawings used in the description of the embodiments of this disclosure will be briefly introduced below. Obviously, the drawings described below are merely some exemplary embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on the content of the exemplary embodiments of this disclosure and these drawings without any creative effort.
[0033] Figure 1 This is a schematic diagram of the structure of one embodiment of the present disclosure;
[0034] Figure 2 This is a schematic diagram of the connection structure between the drain pipe, the delivery pump, and the settling tank in one embodiment of this disclosure;
[0035] Figure 3 This is a schematic diagram of the connection structure between the spiral guide plate and the drain pipe in one embodiment of this disclosure;
[0036] Figure 4 This is a schematic diagram of the spiral guide plate in one direction in one embodiment of the present disclosure;
[0037] Figure 5 This is a schematic diagram of the spiral guide plate in another direction in one embodiment of the present disclosure.
[0038] In the diagram: 1. Shell, 2. Filter screen, 3. Quartz sand filter layer, 4. Activated carbon filter layer, 5. Settling tank, 6. Liquid inlet, 7. Liquid outlet, 8. Slag outlet, 9. Support leg, 10. Seal, 11. Transfer pump, 12. Drain pipe, 13. Flocculant dosing pipe, 14. Spiral guide plate, 15. Spiral channel, 16. First flange, 17. Second flange, 18. Third flange, 19. First retaining ring, 20. Second retaining ring, 21. Cover, 22. Backwash pipe, 23. Backwash nozzle. Detailed Implementation
[0039] The present disclosure will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present disclosure and are not intended to limit the scope of the disclosure.
[0040] To keep the drawings concise, each drawing only schematically shows the parts relevant to the disclosure; these do not represent the actual structure of the product. Furthermore, for ease of understanding, in some drawings, only one of components with the same structure or function is schematically shown, or only one is labeled. In this document, "one" not only means "only one," but can also mean "more than one," and "several" includes "two" and "more than two."
[0041] In this document, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linkage" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this disclosure based on the specific circumstances.
[0042] In this disclosure, unless otherwise expressly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.
[0043] In the description of this embodiment, terms such as "upper," "lower," "left," and "right" are based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of description and simplification of operation, and are not intended to 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 disclosure.
[0044] Furthermore, in the description of this application, the terms "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.
[0045] like Figure 1The diagram illustrates an alumina evaporation circulating water heat recovery device according to an embodiment of this disclosure, for connection to a settling hot water station. It includes a shell 1, a filter screen 2, a quartz sand filter layer 3, an activated carbon filter layer 4, and a settling tank 5. The shell 1 has an inlet 6 and an outlet 7. The inlet 6 is used to communicate with the settling hot water station. The filter screen 2 is disposed inside the shell 1, with the inlet 6 located on one side of the filter screen 2 and the outlet 7 located on the other side. The quartz sand filter layer 3 is disposed inside the shell 1 and located between the filter screen 2 and the outlet 7. The activated carbon filter layer 4 is disposed inside the shell 1 and located between the quartz sand filter layer 3 and the outlet 7. The inlet of the settling tank 5 is connected to the outlet 7.
[0046] For example, such as Figure 1 As shown, after circulating water enters the shell 1 through the inlet 6, it first passes through the filter screen 2 for coarse filtration, removing rust and other metal slag and large solid impurities caused by pipeline corrosion. Then, it passes through the quartz sand filter layer 3, where fine particles are screened out. When passing through the activated carbon filter layer 4, pigment molecules come into contact with the high specific surface area of the activated carbon and are trapped under the adsorption of active functional groups, thus completing the adsorption and removal of fine particles and pigments in the circulating water. Finally, it is discharged through the outlet 7 into the settling tank 5. This effectively reduces the impurity content in the circulating water, preventing impurities from accumulating in dead corners of equipment and pipelines, avoiding damage to equipment and pipelines caused by blockages, wear, and scaling, reducing the impact on the thermal energy circulation effect of the pipelines, and improving the waste heat utilization rate of the high-temperature circulating water.
[0047] In some examples, the liquid inlet 6 is located at the lower end of the side wall of the housing 1, the liquid outlet 7 is located at the upper end of the side wall of the housing 1, and the filter screen 2, the quartz sand filter layer 3, and the activated carbon filter layer 4 are arranged sequentially from bottom to top.
[0048] For example, such as Figure 1 As shown, the liquid inlet 6 is located at the lower end of the side wall of the shell 1. After entering the shell 1, the circulating water flows upward and fully contacts the filter screen 2, the quartz sand filter layer 3, and the activated carbon filter layer 4 during the upward process to complete the filtration. This can improve the filtration effect and reduce the load-bearing capacity requirement of the filter screen 2. Impurities settle at the bottom of the shell 1, which is convenient for subsequent cleaning.
[0049] In some examples, the bottom of the housing 1 is conical and has a slag discharge port 8 located at the lower end of the cone. An alumina evaporation circulating water heat recovery device also includes a support leg 9 and a seal 10. The upper end of the support leg 9 is connected to the housing 1 to support the housing 1. There are multiple support legs 9, and all the support legs 9 are arranged around the slag discharge port 8. The seal 10 is detachably installed at the slag discharge port 8.
[0050] For example, such as Figure 1As shown, the bottom of the shell 1 is designed in a conical shape, allowing impurities settled at the bottom to naturally converge towards the discharge port 8. Support legs 9 are arranged around the discharge port 8, providing stable support for the shell 1. A seal 10 is detachably installed at the discharge port 8, ensuring a tight seal and preventing leakage during normal filtration; when cleaning impurities is required, the seal 10 is removed, and the impurities are discharged through the discharge port 8. This facilitates the cleaning of impurities accumulated at the bottom of the shell 1 during filtration, reducing the difficulty of manual cleaning.
[0051] In some examples, the filter screen 2 is detachably connected to the housing 1, the quartz sand filter layer 3 is detachably connected to the housing 1, and the activated carbon filter layer 4 is detachably connected to the housing 1.
[0052] For example, such as Figure 1 As shown, the detachable connection makes it easy to remove the filter screen 2, quartz sand filter layer 3, and activated carbon filter layer 4 from the housing 1 for cleaning, replacement, or maintenance when they are saturated or damaged by adsorbing impurities. This can improve the maintainability of the device, extend its service life, and reduce maintenance costs.
[0053] In some examples, an alumina evaporation circulating water heat recovery device further includes a delivery pump 11, a drain pipe 12, and a flocculant dosing pipe 13. The delivery pump 11 is connected between the drain outlet 7 and the settling tank 5; the drain pipe 12 is connected between the delivery pump 11 and the settling tank 5; and the outlet end of the flocculant dosing pipe 13 is connected to the drain pipe 12.
[0054] For example, such as Figure 1 , Figure 2 and Figure 3 As shown, the transfer pump 11 provides power to draw the filtered circulating water from the drain port 7, and after passing through the drain pipe 12, it is transported to the settling tank 5. Flocculant is injected into the drain pipe 12 using the flocculant dosing pipe 13. The ions or groups generated by the electrolysis of the flocculant attract and flocculate with the tiny suspended particles with opposite charges in the circulating water, forming larger flocs. These flocs are then removed through sedimentation and filtration in the settling tank 5. The application of this dual physical and chemical filtration technology effectively reduces the impurity content of the circulating water, preventing blockage and siltation after the circulating water enters the washing tank. This improves the water quality in the washing tank, further reduces the impact on the pipeline's heat circulation effect, and increases the waste heat utilization rate of the high-temperature circulating water.
[0055] In some examples, an alumina evaporation circulating water heat recovery device also includes a spiral guide plate 14, which is disposed in the drain pipe 12 to form a spiral channel 15 in the drain pipe 12. The outlet end of the flocculant delivery pipe 13 is connected to the end of the spiral channel 15 near the delivery pump 11.
[0056] For example, such as Figure 1 , Figure 2 , Figure 3, Figure 4 and Figure 5 As shown, the flocculant is injected from the end of the spiral channel 15 near the delivery pump 11. When the circulating water flows within the spiral channel 15 between the spiral guide plate 14 and the drain pipe 12, it generates a rotational motion. This rotational flow allows the flocculant and circulating water to mix more thoroughly, promoting the flocculation reaction and improving flocculation efficiency. This enables tiny suspended particles to more effectively agglomerate and settle, further enhancing the purification effect on the circulating water. The spiral guide plate 14 is formed by splicing multiple plates, with both ends of the plates bent in opposite directions, and adjacent plates are arranged perpendicularly.
[0057] In some examples, the drain pipe 12 is detachably connected to the transfer pump 11, and the drain pipe 12 is detachably connected to the settling tank 5.
[0058] For example, such as Figure 1 As shown, the detachable connection allows for easy removal of the drain pipe 12 from the transfer pump 11 and settling tank 5 when it becomes blocked, damaged, or requires maintenance. This facilitates cleaning, repair, or replacement of the drain pipe 12, improving the maintainability and flexibility of the entire device and reducing maintenance difficulty and cost. The transfer pump 11 is mounted on the outer wall of the housing 1, and the connection between the transfer pump 11 and the housing 1 is detachable, facilitating transportation and maintenance.
[0059] In some examples, an alumina evaporation circulating water heat recovery device further includes a first flange 16, a second flange 17, and a third flange 18. The first flange 16 is mounted on the transfer pump 11, and the side of the first flange 16 facing the drain pipe 12 has a first retaining ring 19, which is inserted into the drain pipe 12. The second flange 17 is mounted at the inlet of the settling tank 5, and the side of the second flange 17 facing the drain pipe 12 has a second retaining ring 20, which is inserted into the drain pipe 12. A spiral guide plate 14 is inserted into the drain pipe 12 and clamped between the first retaining ring 19 and the second retaining ring 20. Both ends of the drain pipe 12 are provided with third flanges 18, which are detachably connected to the first flange 16 and the second flange 17.
[0060] For example, such as Figure 2 and Figure 3As shown, the first flange 16 and the third flange 18 cooperate to achieve a reliable connection between the drain pipe 12 and the transfer pump 11. The second flange 17 and the third flange 18 cooperate to achieve a reliable connection between the drain pipe 12 and the settling tank 5. The first retaining ring 19 on the first flange 16 and the second retaining ring 20 on the second flange 17 cooperate to position the spiral guide plate 14, facilitating the installation and disassembly of the drain pipe 12 and the spiral guide plate 14, thereby improving the reliability and maintainability of the device. The first flange 16 and the third flange 18, as well as the second flange 17 and the third flange 18, are locked together by bolts and nuts, ensuring a firm and reliable connection. Disassembly and assembly are convenient and quick, saving time and effort.
[0061] In some examples, an alumina evaporation circulating water heat recovery device further includes a cover 21, a backwash pipe 22, and a backwash nozzle 23. The cover 21 is disposed on the top of the housing 1 and is detachably connected to the housing 1. The backwash pipe 22 is located outside the cover 21. The backwash nozzle 23 is disposed on the cover 21, with its inlet communicating with the backwash pipe 22 and its outlet facing the interior of the housing 1.
[0062] For example, such as Figure 2 and Figure 3 As shown, the cover 21 is detachably installed on the top of the housing 1, facilitating easy access for inspection and maintenance. The cover 21 and housing 1 are connected by bolts, ensuring a secure and reliable connection while allowing for quick and easy assembly and disassembly, saving time and effort. The backwash pipe 22 connects to an external water source, spraying water into the housing 1 through the backwash nozzle 23. This backwashes the filter screen 2, quartz sand filter layer 3, and activated carbon filter layer 4, removing impurities adhering to them and allowing them to settle at the bottom of the housing 1. Regular backwashing effectively restores the filtration performance of the filter screen 2, quartz sand filter layer 3, and activated carbon filter layer 4, extending their service life and reducing replacement frequency.
[0063] In some examples, the backwash nozzle 23 is threaded to the cover 21, and the backwash nozzle 23 is threaded to the backwash pipe 22.
[0064] For example, such as Figure 1 As shown, the threaded connection makes the connection between the backwash nozzle 23 and the cover 21 and the backwash pipe 22 tight and detachable. The backwash nozzle 23 can be installed or removed by rotating it, which facilitates maintenance and replacement when the backwash nozzle 23 is blocked or damaged. This can improve the installation convenience and stability of the backwash nozzle 23, reduce maintenance costs and difficulty, and ensure that the nozzle will not loosen or fall off during the backwashing process.
[0065] It should be noted that the above embodiments are only used to illustrate the technical solutions of this disclosure and are not intended to limit it. Although this disclosure has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of this disclosure without departing from the spirit and scope of the technical solutions of this disclosure, and all such modifications and substitutions should be covered within the scope of the claims of this disclosure.
Claims
1. A heat recovery device for alumina evaporation circulating water, used for connection to a sedimentation hot water station, characterized in that, include: The housing (1) has a liquid inlet (6) and a liquid outlet (7), the liquid inlet (6) being used to communicate with the sedimentation hot water station; The filter screen (2) is disposed inside the housing (1), the liquid inlet (6) is located on one side of the filter screen (2), and the liquid outlet (7) is located on the other side of the filter screen (2). Quartz sand filter layer (3) is disposed inside the housing (1) and located between the filter screen (2) and the drain port (7); Activated carbon filter layer (4) is disposed inside the housing (1) and located between the quartz sand filter layer (3) and the drain port (7); Settling tank (5), the inlet of which is connected to the drain outlet (7).
2. The device according to claim 1, wherein The liquid inlet (6) is located at the lower end of the side wall of the shell (1), the liquid outlet (7) is located at the upper end of the side wall of the shell (1), and the filter screen (2), the quartz sand filter layer (3), and the activated carbon filter layer (4) are arranged sequentially from bottom to top.
3. The device according to claim 2, wherein The bottom of the shell (1) is conical and has a slag discharge port (8), which is located at the lower end of the cone. The alumina evaporation circulating water heat recovery device further includes: Support leg (9), the upper end of the support leg (9) is connected to the housing (1) and is used to support the housing (1). There are multiple support legs (9), and all the support legs (9) are arranged around the slag discharge port (8). A sealing element (10) is detachably disposed at the slag discharge port (8).
4. The heat recovery device according to claim 1, wherein The filter screen (2) is detachably connected to the housing (1), the quartz sand filter layer (3) is detachably connected to the housing (1), and the activated carbon filter layer (4) is detachably connected to the housing (1).
5. The heat recovery device according to claim 1, wherein The alumina evaporation circulating water heat recovery device further includes: A delivery pump (11) is connected between the drain port (7) and the settling tank (5); A drain pipe (12) is connected between the delivery pump (11) and the settling tank (5); Flocculant delivery pipe (13), the outlet end of which is connected to the drain pipe (12).
6. The alumina evaporation circulating water heat recovery device according to claim 5, characterized in that, The alumina evaporation circulating water heat recovery device further includes a spiral guide plate (14), which is disposed in the drain pipe (12) to form a spiral channel (15) in the drain pipe (12). The outlet end of the flocculant delivery pipe (13) is connected to the end of the spiral channel (15) near the delivery pump (11).
7. The water heat recovery device for an alumina evaporation cycle according to claim 6, characterized by The drain pipe (12) is detachably connected to the delivery pump (11), and the drain pipe (12) is detachably connected to the settling tank (5).
8. The water heat recovery device for an alumina evaporation cycle according to claim 6, characterized by The alumina evaporation circulating water heat recovery device further includes: A first flange (16) is mounted on the delivery pump (11). The first flange (16) has a first retaining ring (19) on the side facing the drain pipe (12). The first retaining ring (19) is inserted into the drain pipe (12). The second flange (17) is located at the inlet of the settling tank (5). The second flange (17) has a second retaining ring (20) on the side facing the drain pipe (12). The second retaining ring (20) is inserted into the drain pipe (12). The spiral guide plate (14) is inserted into the drain pipe (12) and clamped between the first retaining ring (19) and the second retaining ring (20). The third flange (18) is provided at both ends of the drain pipe (12). The third flange (18) is detachably connected to the first flange (16), and the third flange (18) is detachably connected to the second flange (17).
9. The hydrothermal heat recovery device for an alumina evaporation circulating water according to claim 5, characterized by The alumina evaporation circulating water heat recovery device further includes: Cover (21), the cover (21) is disposed on the top of the housing (1), and the cover (21) and the housing (1) are detachably connected; A backwash pipe (22) is located outside the cover (21); A backwash nozzle (23) is provided on the cover (21). The inlet of the backwash nozzle (23) is connected to the backwash pipe (22), and the outlet of the backwash nozzle (23) faces the inside of the housing (1).
10. The water heat recovery device for an alumina evaporation cycle according to claim 9, characterized by The backwash nozzle (23) is threadedly connected to the cover (21), and the backwash nozzle (23) is threadedly connected to the backwash pipe (22).