MVR evaporation crystallization drying device for seawater desalination treatment

Abstract

The application discloses a MVR evaporation crystallization drying device for seawater desalination treatment and relates to the technical field of evaporation crystallization drying devices. The MVR evaporation crystallization drying device comprises a precipitation tank and a heating assembly. The precipitation tank is connected with a circulating pump through a pipeline at one side. The heating assembly is arranged at one side of the circulating pump. The heating assembly comprises a device shell. One side of the circulating pump is connected with the device shell through a pipeline. When the MVR evaporation crystallization drying device is used, the outer wall of the heat exchange pipe can be automatically cleaned periodically during the heating process, so that a large amount of scale can be prevented from adhering and being difficult to clean. After seawater is heated, the seawater can be filtered, scale mixing can be avoided, and the filter screen can be impacted periodically during the filtering process, so that scale is prevented from being accumulated on the filter screen and causing the filter screen to be blocked. When the heated seawater is cooled and precipitated, the crystals adhering to the inner wall of the device can be scraped, corrosion of the device caused by long-term adhesion of the crystals can be avoided, and the paddles can be impacted periodically to clean the paddles.

Description

Technical Field

[0001] This invention relates to the field of evaporation crystallization drying equipment, specifically an MVR evaporation crystallization drying equipment for seawater desalination. Background Technology

[0002] Seawater desalination, which involves desalinating seawater to produce fresh water, is an incremental technology for utilizing water resources. It can increase the total amount of fresh water and is not affected by time, space, or climate. It can ensure a stable water supply for drinking water and industrial use for coastal residents. MVR evaporation and crystallization devices can be used to treat seawater during the desalination process.

[0003] Existing MVR evaporation crystallization drying equipment, when treating seawater, is prone to scaling on the surface of heat exchangers due to the high salinity of seawater, which reduces heat transfer efficiency and requires frequent chemical cleaning or mechanical descaling. In addition, microorganisms and suspended solids in seawater can easily form biofilms or inorganic deposits in the equipment, affecting heat transfer efficiency and stability, requiring periodic shutdown for cleaning. Summary of the Invention

[0004] The purpose of this invention is to provide an MVR evaporation crystallization drying apparatus for seawater desalination to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: an MVR evaporation crystallization drying device for seawater desalination, comprising a sedimentation tank and a heating assembly. A circulation pump is connected to one side of the sedimentation tank via a pipe. The heating assembly is disposed on one side of the circulation pump. The heating assembly includes a shell. The shell is connected to one side of the circulation pump via a pipe, and partitions are symmetrically connected inside the shell. Through holes are provided on the partitions. A heat exchange tube is connected to one side of the partition in the through hole. A rotating sleeve is engaged with the other side of the partition in the through hole. An exhaust hole is provided inside the rotating sleeve, and scrapers are symmetrically connected to one side of the rotating sleeve.

[0006] Furthermore, the rotating sleeve is rotatably connected to the partition plate through through holes, and the through holes are arrayed on the partition plate. The rotating sleeve is fitted onto one end of the heat exchange tube, and the scraper is attached to the surface of the heat exchange tube. The exhaust holes are equidistantly distributed in a circle on the rotating sleeve and form a 60° angle with the meridian.

[0007] Furthermore, a filter is connected to one side of the housing via a pipe, and a filter screen is installed inside the filter. A waste discharge trough is opened on one side of the filter, and limit strips are symmetrically connected to both sides of the bottom surface of the filter.

[0008] Furthermore, a collection frame is engaged between the limiting strips, and a baffle is also engaged between the limiting strips. A sealing spring is symmetrically connected to both sides of the baffle, and the baffle is elastically connected to the filter through the sealing spring. The collection frame and the baffle are slidably connected to the filter through the limiting strips, and the collection frame and the baffle are both in contact with the bottom surface of the filter.

[0009] Furthermore, a shaft is rotatably connected to the bottom of the sedimentation tank, and an agitator motor is connected to one side of the shaft via a belt and a pulley. Blades are symmetrically arranged around the shaft, and air jets are symmetrically arranged on both sides of the blades. Control valves are installed in both the air jets and the exhaust holes.

[0010] Furthermore, a drain pipe is connected to the other side of the sedimentation tank, and a drying box is connected to the bottom of the sedimentation tank via a pipe. A partition is provided in the middle of the drying box, and an air pump is connected to the top of the drying box. A discharge door is provided on one side of the drying box.

[0011] Furthermore, a separation tank is connected above the sedimentation tank, and a spiral guide plate is connected inside the separation tank. An inner cylinder is connected to the inner side of the spiral guide plate, and the separation tank is connected to the filter through a pipe.

[0012] Furthermore, the separator has a connecting plate above the inner cylinder, and a guide plate is connected to one side of the connecting plate. The separator also has a defoaming plate above the guide plate and a feed pipe on one side of the separator.

[0013] Furthermore, an exhaust pipe is connected to the top of the separation tank, and two branch pipes are provided on the exhaust pipe. One branch pipe of the exhaust pipe is connected to the inside of the filter, and the other branch pipe of the exhaust pipe is connected to the shaft and the bottom of the drying chamber, respectively.

[0014] Furthermore, the exhaust pipe is connected to the upper part of the casing via an external compressor, and a return pipe is provided at the lower part of the drying chamber, which is connected to the exhaust pipe. The exhaust pipe is also connected to an external steam pipeline.

[0015] This invention provides an MVR evaporation crystallization drying device for seawater desalination, which has the following advantages: During use, the outer wall of the heat exchange tube can be automatically cleaned periodically during the heating process to avoid the adhesion of large amounts of scale that are difficult to clean. After the seawater is heated, it can be filtered to prevent scale from mixing in. During the filtration process, the filter screen can be periodically impacted to prevent scale from accumulating and clogging it. When the heated seawater cools and settles, the crystals adhering to the inner wall of the device can be scraped off to prevent long-term adhesion of crystals from causing corrosion to the device. The impeller can also be periodically impacted for cleaning.

[0016] 1. In this invention, when heating seawater, steam and secondary steam enter the shell and then enter the heat exchange tubes through the rotating sleeve. At the same time, seawater is sent into the middle of the shell, so that the steam heats the seawater through the heat exchange tubes. During the heating process, the steam can periodically drive the rotating sleeve to rotate, thereby driving the scraper to clean the outer wall of the heat exchange tubes and remove the adhering scale. After the steam condenses at the bottom of the shell, it is discharged into the condensate tank to complete the desalination treatment, and can also participate in the treatment process again.

[0017] 2. After the seawater is heated, the present invention can filter it to remove the scale mixed in with the seawater, so as to avoid the scale from mixing into the seawater and causing pipe blockage. When filtering the seawater, secondary steam can be used to periodically impact the filter screen, thereby preventing scale from accumulating on the filter screen and clogging it. At the same time, the scale shaken off by the impact can be collected for centralized cleaning. The cleaning of scale can also prevent the material liquid from leaking from the waste discharge tank.

[0018] 3. In this invention, after seawater enters the separation tank, it can be partially vaporized to form steam, which is then separated along the spiral guide plate within the separation tank. The steam carries some small particles upwards and separates from the steam below the demister plate. The steam is discharged through the guide pipe along the guide plate. The secondary steam can then be pressurized and heated by an external compressor through the outlet pipe and participate in the processing. When the seawater after steam separation enters the sedimentation tank for sedimentation, the stirring motor can drive the blades to rotate slowly inside the sedimentation tank via the shaft, scraping off the adhering material accumulated on the inner wall of the sedimentation tank to prevent long-term adhesion and corrosion of the inner wall of the sedimentation tank. When the crystal slurry at the bottom of the sedimentation tank is discharged, the air pump can first draw a negative pressure in the upper part of the drying box to accelerate the flow of the crystal slurry. The secondary steam can also be introduced into the lower part of the drying box and dried through the separator plate. The negative pressure in the drying box can also accelerate the separation of water. The concentrated liquid in the sedimentation tank can be discharged through the drain pipe and no longer participates in the recycling process. Attached Figure Description

[0019] Figure 1 This is a three-dimensional cross-sectional view of an MVR evaporation crystallization drying apparatus for seawater desalination according to the present invention.

[0020] Figure 2 This is a half-section three-dimensional exploded structural diagram of the heating component of an MVR evaporation crystallization drying device for seawater desalination according to the present invention.

[0021] Figure 3 This is a half-section three-dimensional exploded view of the filter of an MVR evaporation crystallization drying device for seawater desalination according to the present invention.

[0022] Figure 4 This is a schematic diagram of the overall three-dimensional structure of an MVR evaporation crystallization drying device for seawater desalination according to the present invention.

[0023] Figure 5 This is a half-section three-dimensional exploded view of the sedimentation tank of an MVR evaporation crystallization drying device for seawater desalination according to the present invention.

[0024] Figure 6 This is a half-section three-dimensional structural diagram of the drying box of an MVR evaporation crystallization drying device for seawater desalination according to the present invention.

[0025] In the diagram: 1. Sedimentation tank; 2. Circulation pump; 3. Heating assembly; 301. Shell; 302. Baffle plate; 303. Through hole; 304. Heat exchange tube; 305. Rotary sleeve; 306. Exhaust port; 307. Scraper; 4. Filter; 5. Filter screen; 6. Waste discharge trough; 7. Limiting strip; 8. Collection frame; 9. Baffle plate; 10. Sealing spring; 11. Shaft; 12. Agitator motor; 13. Paddle; 14. Jet nozzle; 15. Drain pipe; 16. Drying oven; 17. Dividing plate; 18. Air pump; 19. Discharge gate; 20. Separator tank; 21. Spiral guide plate; 22. Inner cylinder; 23. Connecting plate; 24. Flow guide plate; 25. Defoaming plate; 26. Feed pipe; 27. Air outlet pipe. Detailed Implementation

[0026] Please see Figures 1 to 6 The present invention provides a technical solution: an MVR evaporation crystallization drying device for seawater desalination, comprising a sedimentation tank 1 and a heating component 3. A circulation pump 2 is connected to one side of the sedimentation tank 1 via a pipe. The heating component 3 is disposed on one side of the circulation pump 2. The heating component 3 includes a housing 301. The housing 301 is connected to one side of the circulation pump 2 via a pipe. A partition plate 302 is symmetrically connected inside the housing 301. A through hole 303 is provided on the partition plate 302. A heat exchange tube 304 is connected to one side of the partition plate 302 of the housing 301 at the through hole 303. A rotating sleeve 305 is engaged and connected inside the through hole 303 on the other side of the partition plate 302 of the housing 301. An exhaust hole 306 is provided inside the rotating sleeve 305. A scraper 307 is symmetrically connected to one side of the rotating sleeve 305.

[0027] Please see Figures 1 to 3The rotating sleeve 305 is rotatably connected to the partition plate 302 through the through hole 303, and the through hole 303 is arrayed on the partition plate 302. The rotating sleeve 305 is sleeved on one end of the heat exchange tube 304, and the scraper 307 is attached to the surface of the heat exchange tube 304. The exhaust hole 306 is equidistantly distributed in a circle on the rotating sleeve 305 and forms a 60° angle with the meridian. A filter 4 is connected to one side of the shell 301 through a pipe, and a filter screen 5 is installed inside the filter 4. A waste discharge groove 6 is opened on one side of the filter 4, and limit strips 7 are symmetrically connected on both sides of the bottom surface of the filter 4. A collection frame 8 is engaged between the limit strips 7, and a baffle 9 is also engaged between the limit strips 7. A sealing spring 10 is symmetrically connected on both sides of the baffle 9, and the baffle 9 is elastically connected to the filter 4 through the sealing spring 10. The collection frame 8 and the baffle 9 are slidably connected to the filter 4 through the limit strips 7, and the collection frame 8 and the baffle 9 are attached to the bottom surface of the filter 4.

[0028] The specific operation is as follows: When heating seawater, steam and secondary steam enter the shell 301 and then enter the heat exchange tube 304 through the rotating sleeve 305. At the same time, seawater is sent into the middle of the shell 301, so that steam heats the seawater through the heat exchange tube 304. During the heating process, the steam can periodically drive the rotating sleeve 305 to rotate, which in turn drives the scraper 307 to clean the outer wall of the heat exchange tube 304 and remove the adhering scale. After the steam condenses at the bottom of the shell 301, it is discharged into the condensate tank to complete the desalination treatment, or it can participate in the treatment process again. After the seawater is heated, it can be filtered to remove the scale mixed in with the seawater, so as to prevent the scale from mixing into the seawater and causing pipe blockage. When filtering seawater, secondary steam can be used to periodically impact the filter screen 5, so as to prevent scale from accumulating on the filter screen 5 and clogging it. At the same time, the scale shaken off by the impact is collected for centralized cleaning. When cleaning scale, it can also prevent the material liquid from leaking from the waste discharge tank 6.

[0029] Please see Figure 1 and Figures 4 to 6A shaft 11 is rotatably connected to the bottom of the sedimentation tank 1, and an agitator motor 12 is connected to one side of the shaft 11 via a belt and pulley. Blades 13 are symmetrically arranged around the shaft 11, and air jets 14 are symmetrically arranged on both sides of the blades 13. Control valves are installed in both the air jets 14 and the exhaust port 306. A drain pipe 15 is connected to the other side of the sedimentation tank 1, and a drying chamber 16 is connected to the bottom of the sedimentation tank 1 via a pipe. A dividing plate 17 is installed in the middle of the drying chamber 16, and an air pump 18 is connected to the top of the drying chamber 16. A discharge door 19 is installed on one side of the drying chamber 16. A separation tank 20 is connected above the sedimentation tank 1, and a spiral guide plate 21 is connected inside the separation tank 20. An inner cylinder 22 is connected to the inner side of the spiral guide plate 21. The separator 20 is connected to the filter 4 via a pipe. A connecting plate 23 is provided above the inner cylinder 22 of the separator 20, and a guide plate 24 is connected to one side of the connecting plate 23. A defoaming plate 25 is provided above the guide plate 24 of the separator 20, and a material guide pipe 26 is provided on one side of the separator 20. An exhaust pipe 27 is connected to the top of the separator 20, and two branch pipes are provided on the exhaust pipe 27. One branch pipe on the exhaust pipe 27 is connected to the inside of the filter 4, and the other branch pipe on the exhaust pipe 27 is connected to the shaft 11 and the bottom of the drying box 16, respectively. The exhaust pipe 27 is connected to the upper part of the shell 301 through an external compressor. A return pipe is provided at the bottom of the drying box 16, and the return pipe is connected to the exhaust pipe 27. The exhaust pipe 27 is connected to the external steam pipeline.

[0030] The specific operation is as follows: After seawater enters the separator 20, it can be partially vaporized to form steam, which is then separated within the separator 20 along the spiral guide plate 21. The steam carries some small particles upwards and separates from the steam below the demister plate 25. The steam is then discharged along the guide plate 24 through the feed pipe 26. The secondary steam can then be pressurized and heated by an external compressor through the outlet pipe 27 and participate in the treatment process. When the seawater after steam separation enters the sedimentation tank 1 for sedimentation, the agitator motor 12 can drive the impeller 13 through the shaft 11. The sedimentation tank 1 rotates slowly to scrape off the adhesive material accumulated on the inner wall of the sedimentation tank 1, preventing long-term adhesion that could lead to corrosion of the inner wall of the sedimentation tank 1. When the crystal slurry at the bottom of the sedimentation tank 1 is discharged, the air pump 18 can first draw a negative pressure in the upper part of the drying box 16 to accelerate the flow of the crystal slurry. Secondary steam can also be introduced into the lower part of the drying box 16 and dried through the dividing plate 17. The negative pressure in the drying box 16 can also accelerate the separation of water. The concentrate in the sedimentation tank 1 can be discharged through the drain pipe 15 and will no longer participate in the recycling process.

[0031] In summary, this MVR evaporation crystallization drying device for seawater desalination first introduces steam and secondary steam into the shell 301, where they are blocked at the top by the partition 302. The steam then enters the heat exchange tube 304 through the rotating sleeve 305. Simultaneously, raw seawater is introduced into the middle of the shell 301, allowing steam to heat the seawater through the heat exchange tube 304. During the heating process, the control valve in the exhaust port 306 is periodically opened to allow steam to be ejected from the rotating sleeve 305 through the exhaust port 306. This causes the rotating sleeve 305 to rotate within the through hole 303, which in turn drives the scraper 307 to clean the outer wall of the heat exchange tube 304, removing the adhering scale. After the steam condenses at the bottom of the shell 301, it is discharged into the condensate tank to complete the desalination process. It can also participate in the treatment process again. The non-condensable gases contained in the steam leave the shell through another pipe.

[0032] After the seawater is heated, it enters the filter 4, where the filter screen 5 filters it, removing scale mixed in with the seawater. This prevents scale from flowing through the pipes and causing blockages. During seawater filtration, secondary steam periodically impacts the filter screen 5, preventing scale buildup and blockages. The scale dislodged by the impact leaves the filter 4 through the waste discharge tank 6 and enters the collection frame 8 for easy cleaning. To clean the scale in the collection frame 8, simply move the collection frame 8 along the limiting strip 7 from the filter... The device 4 can be disassembled by sliding it out from below. At the same time, the baffle 9 can slide between the limiting strips 7 under the action of the sealing spring 10 to seal the waste discharge tank 6 and prevent the liquid from leaking from the waste discharge tank 66. After cleaning, simply slide the collection frame 8 along the limiting strip 7 to the bottom of the waste discharge tank 6 to collect the scale again. At the same time, the baffle 9 can be moved and the sealing spring 10 can be compressed. The limiting strip 7 can restrict the collection frame 8 and the baffle 9 to prevent them from deviating during the movement, which would cause the waste discharge tank 6 to be unable to be sealed and leak.

[0033] After the seawater is filtered and enters the separator 20, it can be partially vaporized to form steam and flow downward along the spiral guide plate 21 in the separator 20. Separation occurs at the bottom of the inner cylinder 22. The steam carries some small particles upward through the connecting plate. The small particles are separated from the steam below the demister plate 25 and discharged through the feed pipe 26 along the guide plate 24. The secondary steam captures liquid foam through the demister plate 25. The pure steam passes through the exhaust pipe 27 and is pressurized and heated by an external compressor before it can participate in the treatment of the seawater.

[0034] When the seawater after steam separation enters the settling tank 1 for sedimentation, the agitator motor 12 drives the impeller 13 to rotate slowly inside the settling tank 1 via the shaft 11, scraping off the adhering material accumulated on the inner wall of the settling tank 1 to prevent long-term adhesion and corrosion of the inner wall. While the shaft rotates, the control valve in the jet nozzle 14 is periodically opened, allowing secondary steam to be ejected from the jet nozzle 14 on the shaft 11, impacting the surface of the impeller 13 and preventing crystal adhesion. The concentrated liquid forms a crystal slurry at the bottom of the settling tank 1, which is then discharged into the drying chamber 16 through a pipeline. The remaining high-concentration waste liquid is discharged through the drain pipe 15. When the crystal slurry at the bottom of the settling tank 1 is discharged, the air pump 18 can first draw the upper part of the drying box 16 into negative pressure to accelerate the flow of crystal slurry. Secondary steam can also be introduced into the lower part of the drying box 16 and dried through the dividing plate 17. The negative pressure in the drying box 16 can also accelerate the separation of water. The low temperature steam discharged from the drying box 16 returns to the outlet pipe 27 through the return pipe and re-enters the shell 301 to participate in the heating cycle. After drying is completed, the discharge door 19 is opened to discharge the crystals in the drying box 16 for the next drying process.

[0035] It should be noted that, in this document, the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0036] This article uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only for the purpose of helping to understand the method and core ideas of the present invention. The above descriptions are only preferred embodiments of the present invention. It should be noted that due to the limitations of textual expression, while there are objectively infinite specific structures, those skilled in the art can make several improvements, modifications, or changes without departing from the principles of the present invention, and can also combine the above technical features in an appropriate manner. These improvements, modifications, changes, or combinations, or the direct application of the inventive concept and technical solution to other situations without modification, should all be considered within the scope of protection of the present invention.

Claims

1. An MVR evaporation crystallization drying apparatus for seawater desalination, characterized in that, The device includes a sedimentation tank (1) and a heating assembly (3). A circulation pump (2) is connected to one side of the sedimentation tank (1) via a pipe. The heating assembly (3) is located on one side of the circulation pump (2). The heating assembly (3) includes a housing (301). The housing (301) is connected to one side of the circulation pump (2) via a pipe. Baffles (302) are symmetrically connected inside the housing (301). Through holes (303) are provided on the baffles (302). A heat exchange tube (304) is connected to one side of the baffle (302) at the through hole (303). A rotating sleeve (305) is engaged inside the through hole (303) of the baffle (302) on the other side of the housing (301). An exhaust port (306) is provided inside the sleeve (305), and scrapers (307) are symmetrically connected to one side of the sleeve (305). The sleeve (305) is rotatably connected to the partition plate (302) through a through hole (303), and the through holes (303) are arrayed on the partition plate (302). The sleeve (305) is fitted onto one end of the heat exchange tube (304), and the scrapers (307) are attached to the surface of the heat exchange tube (304). The exhaust ports (306) are equidistantly distributed in a circle on the sleeve (305). A filter (4) is connected to one side of the shell (301) through a pipe, and a filter screen (5) is provided inside the filter (4). A waste discharge groove (6) is provided on one side of the filter (4), and a limited number of pipes are symmetrically connected to the bottom surface of the filter (4). The limiting strips (7) are engaged with a collection frame (8), and the limiting strips (7) are also engaged with a baffle (9). The baffle (9) is symmetrically connected to both sides with sealing springs (10), and the baffle (9) is elastically connected to the filter (4) through the sealing springs (10). The collection frame (8) and the baffle (9) are slidably connected to the filter (4) through the limiting strips (7), and the collection frame (8) and the baffle (9) are both in contact with the bottom surface of the filter (4). The bottom of the sedimentation tank (1) is rotatably connected with a shaft (11), and one side of the shaft (11) is connected to an agitator motor (12) through a belt and a pulley. The shaft (11) is symmetrically arranged with blades (13) around its perimeter. 1) Air jets (14) are symmetrically arranged on both sides of the blade (13). Control valves are provided in both the air jets (14) and the exhaust holes (306). A separation tank (20) is connected above the sedimentation tank (1). A spiral guide plate (21) is connected inside the separation tank (20). An inner cylinder (22) is connected inside the spiral guide plate (21). The separation tank (20) is connected to the filter (4) through a pipe. A connecting plate (23) is provided above the inner cylinder (22) of the separation tank (20). A guide plate (24) is connected to one side of the connecting plate (23). A defoaming plate (25) is provided above the guide plate (24) of the separation tank (20). A feed pipe (26) is provided on one side of the separation tank (20).

2. The MVR evaporation crystallization drying apparatus for seawater desalination according to claim 1, characterized in that, The sedimentation tank (1) is connected to a drain pipe (15) on the other side, and a drying box (16) is connected to the bottom of the sedimentation tank (1) through a pipe. A partition plate (17) is provided in the middle of the drying box (16), and an air pump (18) is connected to the top of the drying box (16). A discharge door (19) is provided on one side of the drying box (16).

3. The MVR evaporation crystallization drying apparatus for seawater desalination according to claim 1, characterized in that, The separation tank (20) is connected to an exhaust pipe (27) at the top, and the exhaust pipe (27) is provided with two branch pipes. One branch pipe of the exhaust pipe (27) is connected to the inside of the filter (4), and the other branch pipe of the exhaust pipe (27) is connected to the shaft (11) and the lower part of the drying box (16) respectively.

4. The MVR evaporation crystallization drying apparatus for seawater desalination according to claim 3, characterized in that, The exhaust pipe (27) is connected to the upper part of the housing (301) via an external compressor. The lower part of the drying box (16) is provided with a return pipe, which is connected to the exhaust pipe (27). The exhaust pipe (27) is connected to an external steam pipeline.

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