Reverse osmosis membrane anti-pollution device in seawater desalination

Abstract

The invention discloses a reverse osmosis membrane anti-pollution device in seawater desalination, which comprises a pretreatment module, a front desalination module, a mixed disinfection tank and a rear desalination module, the pretreatment module, the mixed disinfection tank and the rear desalination module are sequentially connected, the front desalination module is connected in parallel between the pretreatment module and the mixed disinfection tank, and the rear desalination module is connected in parallel between the front desalination module and the mixed disinfection tank. According to the invention, two modes of evaporation desalination and reverse osmosis membrane desalination are adopted to desalinate the seawater, the seawater desalination efficiency is improved, the mixed disinfection tank is additionally arranged in front of the reverse osmosis filter assembly, and the mixed disinfection tank is used for mixing the seawater treated by the front desalination module and the seawater pretreated by the front desalination module. High-temperature seawater in the evaporation pond and pretreated normal-temperature seawater are mixed and subjected to secondary sterilization and disinfection, so that the seawater is always kept at the optimal filtering water temperature of about 25 DEG C, the optimal desalination efficiency of a subsequent filtering assembly is ensured, and biological pollution of ultrafiltration and reverse osmosis filtering assemblies can be reduced.

Description

Technical Field

[0001] The present invention relates to the field of seawater desalination equipment, and particularly to an anti-pollution device for reverse osmosis membranes in seawater desalination. Background Art

[0002] With the development of the economy and the continuous improvement of people's living standards, the demand for water is increasing. Not only is the domestic water consumption increasing, but the water consumption for urban greening, road maintenance, and industrial use is also increasing day by day, and the latter has a huge water consumption. The shortage of available fresh water resources in the world is becoming increasingly obvious, prompting many regions and countries to search for new water sources. Among numerous water sources, seawater desalination is one of the important ways to solve the water resource shortage.

[0003] Our company applied for a patent for a seawater desalination device and process with the patent number 202411657860.2 in 2024, which records a technical solution that combines evaporation desalination and membrane desalination. Without increasing energy consumption, the overall desalination efficiency of seawater is improved.

[0004] However, our company found problems during the subsequent verification and optimization process. The seawater in the evaporation pond enters the filtration component for reverse osmosis membrane filtration after partial evaporation. However, the seawater in the evaporation pond reaches a relatively high temperature under the heating of the heat exchange tubes, far exceeding the optimal filtration temperature of the ultrafiltration membrane and the reverse osmosis membrane. This reduces the desalination efficiency and is also likely to accelerate the aging and damage of the filtration membrane. In addition, the seawater that has been pretreated for disinfection and sterilization will grow again after passing through the pipeline and the evaporation pond, providing a suitable environment for microorganisms, and causing biological pollution to the subsequent filtration membrane. This is the problem that needs to be solved. Summary of the Invention

[0005] In order to make up for the above deficiencies, the present invention provides an anti-pollution device for reverse osmosis membranes in seawater desalination, which is upgraded and improved on the original basis to protect the filtration component and extend its service life.

[0006] The present invention is realized through the following technical solutions:

[0007] An anti-pollution device for reverse osmosis membranes in seawater desalination, characterized in that it includes a pretreatment module, a pre-desalination module, a mixing and disinfection tank, and a post-desalination module. The pretreatment module, the mixing and disinfection tank, and the post-desalination module are connected in sequence. The pre-desalination module is connected in parallel between the pretreatment module and the mixing and disinfection tank. The mixing and disinfection tank is used to mix the seawater treated by the pre-desalination module and the pretreated seawater, and perform sterilization and disinfection. An inlet is provided on the side wall of the upper part of the mixing and disinfection tank, and an outlet is provided on the side wall of the lower part of the mixing and disinfection tank. An annular groove is fixed on the inner wall of the tank body of the mixing and disinfection tank. The annular groove divides the inner part of the tank into an upper space and a lower space that are connected. A spoiler is fixed in the annular groove, and a frustum-shaped overflow weir is fixed on the inner side of the annular groove. The inlet is connected to the annular groove. An inverted frustum-shaped deflector is fixed on the inner wall of the overflow weir. An installation seat is provided on the lower wall inside the tank body of the mixing and disinfection tank. A support rod is fixed on the installation seat. A buffer cone is fixed at the top of the support rod. The deflector faces the buffer cone. A number of ultraviolet lamp columns evenly distributed in the circumferential direction are also provided on the installation seat. A number of layers of flow stabilizer disks are fixed on the support rod. The ultraviolet lamp columns pass through the flow stabilizer disks and approach the bottom of the annular groove.

[0008] Further optimized, a sealing turntable is fixed at the bottom of the tank body of the mixing and disinfection tank. The installation seat is fixed on the sealing turntable. An auxiliary handle is fixed on the topmost layer of the flow stabilizer disk. The bottom of the ultraviolet lamp column is threadedly connected to the installation seat. A maintenance door is provided on the bottom of the annular groove.

[0009] Further optimized, a lithium battery is provided inside the ultraviolet lamp column, and a magnetic charging port is provided at the top of the ultraviolet lamp column.

[0010] Further optimized, a water inlet pipe is fixed on the inlet. A spoiler paddle is provided inside the water inlet pipe. The water inlet pipe is connected to two water supply pipes. The first water supply pipe is connected to the pre-desalination module, and the second water supply pipe is connected to the pretreatment module.

[0011] Further optimized, flow regulating valves are provided on both of the two water supply pipes. A thermometer is suspended downward from the tank door at the top of the mixing and disinfection tank. The thermometer is immersed in water to keep the water temperature in the tank at 25 - 30 degrees.

[0012] Further optimized, a water outlet pipe is fixed on the outlet. An anti-vortex ring is fixed inside the water outlet pipe. A filter box is fixedly connected to the water outlet pipe. The filter box is connected to the post-desalination module.

[0013] Further optimized, a detachable sealing cover is provided on the filter box. A sealing frame is fixed on the inner wall of the filter box. A sealing groove is provided on the sealing frame. A filter element frame is inserted into the sealing groove. A filter element is fixed on the filter element frame. A sealing strip matching the sealing groove is fixed on the inner wall of the sealing cover.

[0014] Further optimized, the pretreatment module includes a clarification tank, a sand filter, a security filter and a reservoir connected in sequence. The reservoir is connected to the pre-desalination module and the mixing disinfection tank respectively through a circulation pump and a water supply pipe to provide pretreated normal-temperature seawater.

[0015] Further optimized, the pre-desalination module includes an evaporation tank and a heating device. A fresh water collection device is provided above the evaporation tank. The heating device includes a solar collector, a heat exchange pipe and a medium pump, which form a loop. And part of the heat exchange pipes are arranged in the evaporation tank to raise the temperature of the seawater in the evaporation tank. The evaporation tank is connected to the mixing disinfection tank through a circulation pump and a water supply pipe. The evaporation tank enters water from the lower side and exits water from the upper side to provide high-temperature seawater with part of the water evaporated to the mixing disinfection tank.

[0016] Further optimized, the post-desalination module includes a nanofiltration membrane module, a reverse osmosis membrane module and an energy recovery device. The mixing disinfection tank is connected to the nanofiltration membrane module through a booster pump and a pipeline. The energy recovery device is arranged at the wastewater outlet ends of the nanofiltration membrane module and the reverse osmosis membrane module.

[0017] The beneficial effects of the present invention are as follows:

[0018] The present invention desalinates seawater by two methods of evaporation desalination and reverse osmosis membrane desalination. The combination of the two improves the overall desalination efficiency of seawater without increasing energy consumption.

[0019] The mixing disinfection tank in the present invention further sterilizes and disinfects the seawater entering the post-desalination module, kills the microorganisms regrown in the pipeline and the evaporation tank, avoids biological contamination of the ultrafiltration and reverse osmosis filtration components, and prolongs their service life.

[0020] The mixing disinfection tank in the present invention mixes the high-temperature seawater in the evaporation tank with the pretreated normal-temperature seawater through the mixing disinfection tank, so that the seawater always maintains the best filtration water temperature of about 25 degrees, and improves the desalination efficiency of the reverse osmosis filtration components. Correspondingly, in the present invention, whether in winter or summer, or other different situations, only by appropriately adjusting the water inflow of the two water supply pipelines, the best desalination efficiency of the subsequent filtration components can be ensured. Without increasing energy consumption, the present invention further improves the overall seawater desalination efficiency.

[0021] A filter box is installed behind the mixing and disinfection tank to intercept larger particles such as microorganisms killed in the tank to prevent them from entering the ultrafiltration and reverse osmosis filtration components, reducing the number of backwashing times for both. The filter element of the filter box has low cost and is easy to replace.

[0022] The mixed disinfection tank uses a rechargeable ultraviolet lamp column with an easy-to-assemble and disassemble structure. It can be removed and replaced at regular intervals. No other wiring is required in the tank except for the thermometer, which is simple and convenient. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the internal structure of the mixing and sterilizing tank in the present invention.

[0024] Figure 2 It is a schematic diagram of the process of the present invention.

[0025] Figure 3 The internal structure of the mixing and sterilizing tank in the present invention is shown in FIG. Figure 2 .

[0026] Figure 4 for Figure 1 Enlarged view of point A in the middle.

[0027] Figure 5 It is a cross-sectional view of the mixing and sterilizing tank in the present invention.

[0028] Figure 6 It is a three-dimensional diagram of the mixing and sterilizing tank in the present invention.

[0029] In the figure: 1. mixing disinfection tank; 11. tank door; 12. water inlet; 122. spoiler paddle; 13. water outlet; 131. water outlet pipe; 132. anti-vortex ring; 14. sealing turntable; 15. mounting seat; 21. water supply pipe 1; 22. water supply pipe 2; 3. annular groove; 31. maintenance door; 32. spoiler; 33. overflow weir; 34. guide plate; 4. ultraviolet lamp column; 5. support rod; 51. buffer cone; 52. flow stabilizing disk; 53. auxiliary handle; 6. thermometer; 7. filter box; 71. sealing cover; 72. filter element; 73 filter element frame; 74. sealing frame. DETAILED DESCRIPTION

[0030] In order to clearly illustrate the technical features of the present solution, the present invention is described in detail below through specific implementation methods and in conjunction with the accompanying drawings. In the description of the present invention, it should be noted that the terms "left", "right", "front", "back", "inside", "outside" and the like indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.

[0031] like Figures 1-6As shown in the figure, the present invention provides an anti-fouling device for reverse osmosis membranes in seawater desalination, which includes a pretreatment module, a pre-desalination module, a mixing and disinfection tank, and a post-desalination module. The pretreatment module, the mixing and disinfection tank, and the post-desalination module are connected in sequence. The pre-desalination module is connected in parallel between the pretreatment module and the mixing and disinfection tank. The pre-desalination module uses evaporation desalination, and the post-desalination module uses membrane desalination. The combination of the two methods improves the overall desalination efficiency of seawater. The mixing and disinfection tank is used to mix seawater at a relatively high temperature and pretreated normal-temperature seawater, so that the seawater in the tank maintains an optimal filtration water temperature of about 25 degrees Celsius. At the same time, the mixing and disinfection tank can also perform secondary sterilization and disinfection on the seawater in the tank.

[0032] Further, an inlet 12 is provided on the side wall of the upper part of the mixing and disinfection tank 1, and an outlet 13 is provided on the side wall of the lower part of the mixing and disinfection tank. An annular groove 3 is fixed on the inner wall of the tank body of the mixing and disinfection tank 1. The annular groove 3 divides the inner part of the tank into a connected upper space and a lower space. A number of flow disturbing plates 32 are fixed in the annular groove 3. An inverted frustum-shaped overflow weir 33 is fixed on the inner side of the annular groove 3. The inlet 12 is communicated with the annular groove 3. An inverted frustum-shaped guide plate 34 is fixed on the inner wall of the overflow weir 33. High-temperature seawater and normal-temperature seawater enter the upper space from the inlet 12, are mixed in the annular groove 3, overflow from the overflow weir 33 in the middle of the annular groove, and flow into the lower space through the guide plate 34.

[0033] An installation seat 15 is provided on the lower wall inside the tank body of the mixing and disinfection tank 1. A support rod 5 is fixed on the installation seat. A buffer cone 51 is fixed at the top of the support rod 5. The guide plate 34 faces the buffer cone 51. A number of ultraviolet lamp columns 4 are evenly distributed circumferentially on the installation seat 15. A number of layers of flow stabilizing disks 52 are also fixed on the support rod 5. The ultraviolet lamp columns 4 pass through the flow stabilizing disks 52 and approach the bottom of the annular groove 3. The seawater in the lower space inside the tank is sterilized and disinfected by the ultraviolet lamp columns 4. Among them, the flow stabilizing disks and the buffer cone can keep the seawater in the lower space as calm as possible. After the seawater enters the lower space from the upper part and is irradiated by the ultraviolet lamp columns for more than 20 minutes, it flows out from the outlet 13. The ultraviolet light performs secondary disinfection and sterilization on the seawater, killing the microorganisms that grow again in the pipeline and the evaporation pond, avoiding biological pollution to the ultrafiltration and reverse osmosis filtration components, and prolonging their service life.

[0034] As a preferred implementation, as Figure 3 、 5As shown in the figure, a sealing turntable 14 is fixed at the bottom of the tank body of the mixing disinfection tank 1, and the mounting seat 15 is fixed on the sealing turntable. An auxiliary handle 53 is fixed on the uppermost flow stabilizing plate 52. The bottom of the ultraviolet lamp post 4 is threadedly connected to the mounting seat 15. A maintenance door 31 is opened on the bottom of the annular groove 3. When the equipment stops running, the maintenance door can be opened to replace the ultraviolet lamp post 4. The whole mounting seat and the flow stabilizing plate can be rotated through the auxiliary handle and the ultraviolet lamp post 4, and each lamp post can be replaced.

[0035] As a preferred embodiment, a lithium battery is arranged inside the ultraviolet lamp post 4, and a magnetic adsorption type charging port is arranged at the top of the ultraviolet lamp post 4. A soft plug can be arranged on the charging port for sealing. Matching with the above lamp post replacement structure, the lamp post is replaced regularly when the machine stops for charging and maintenance, which can avoid wiring inside the tank.

[0036] As a preferred embodiment, a water inlet pipe is fixed on the water inlet 12, a flow disturbing paddle 122 is arranged inside the water inlet pipe, the water inlet pipe is connected with two water supply pipes. The first water supply pipe 21 is connected with the pre-treatment desalination module, and the heated seawater in the evaporation pond is supplied into the first water supply pipe. The second water supply pipe 22 is connected with the pre-treatment module, and the pre-treated normal temperature seawater is supplied into the second water supply pipe. The flow disturbing paddle plays a role in preliminary mixing.

[0037] As a preferred embodiment, electromagnetic flow regulating valves are arranged on both of the two water supply pipes. A thermometer 6 is suspended downward from the tank door 11 at the top of the mixing disinfection tank, and the thermometer is immersed in water. By adjusting the flow rates of the two water supply pipes, the water temperature in the tank is maintained at 25 - 30 degrees. 25 degrees is the best filtration temperature of the reverse osmosis filtration membrane. In this way, the water temperature supplied to the filtration module can always be maintained at about 25 degrees, ensuring the best desalination efficiency. Correspondingly, no matter in winter, summer or other different situations, the present invention only needs to appropriately adjust the water inflow of the two water supply pipes to ensure the best desalination efficiency of the subsequent filtration module. On the basis of not increasing energy consumption, the present invention further improves the overall seawater desalination efficiency.

[0038] As a preferred embodiment, a water outlet pipe 131 is fixed on the water outlet 13, an anti-eddy current ring 132 is fixed inside the water outlet pipe, and a filter box 7 is fixedly connected to the water outlet pipe. The filter box is connected with the post-treatment desalination module, which can avoid the occurrence of eddy currents in the tank.

[0039] As a preferred embodiment, a detachable sealing cover 71 is provided on the filter cartridge 7. A sealing frame 74 is fixed on the inner wall of the filter cartridge 7. A sealing groove is provided on the sealing frame 74. A filter element frame 73 is inserted into the sealing groove. A filter element 72 is fixed on the filter element frame. A sealing strip matching the sealing groove is fixed on the inner wall of the sealing cover 71. It can intercept larger particles such as killed microorganisms in the tank, prevent them from entering the ultrafiltration and reverse osmosis filtration components, reduce the backwashing times of the two, and the filter element of the filter cartridge has a low cost and is convenient to replace.

[0040] As a preferred embodiment, as Figure 2 shown, the pretreatment module includes a clarifying tank, a sand filter, a security filter, and a reservoir connected in sequence, which respectively perform primary sterilization and disinfection, filtration, and removal of large particle impurities on seawater. The reservoir is connected to the pre-desalination module and the mixing disinfection tank through a circulation pump and a water supply pipe respectively to provide pretreated normal-temperature seawater.

[0041] As a preferred embodiment, as Figure 2 shown, the pre-desalination module includes an evaporation tank and a heating device. A fresh water collection device is provided above the evaporation tank. The heating device includes a solar collector, a heat exchange pipe, and a medium pump, which form a loop, and part of the heat exchange pipe is arranged in the evaporation tank to increase the temperature of the seawater in the evaporation tank. The evaporation tank is connected to the mixing disinfection tank through a circulation pump and a water supply pipe to provide high-temperature seawater with part of the water evaporated to the mixing disinfection tank. In addition, the evaporation tank intakes water from the lower side and discharges water from the upper side. The water evaporates from the surface layer. After the surface seawater evaporates, the concentration is higher, and the seawater with a higher concentration is pumped out from the upper side.

[0042] As a preferred embodiment, the post-desalination module includes a nanofiltration membrane module, a reverse osmosis membrane module, and an energy recovery device. The mixing disinfection tank is connected to the nanofiltration membrane module through a booster pump and a pipeline. The energy recovery device is arranged at the wastewater outlet ends of the nanofiltration membrane module and the reverse osmosis membrane module. The seawater with a higher concentration and temperature after evaporation and the pretreated seawater are mixed in the mixing disinfection tank, then sterilized for the second time, and then filtered through the filtration component at the optimal temperature to obtain fresh water.

[0043] Details not described in the present invention are all well-known technologies in the technical field. Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present invention, and they should all be covered within the scope of the claims of the present invention.

Claims

1. An anti-fouling device for reverse osmosis membranes in seawater desalination, characterized in that: It includes a pretreatment module, a pre-dilution module, a mixed disinfection tank and a post-dilution module. The pretreatment module, the mixed disinfection tank and the post-dilution module are connected in sequence. The pre-dilution module is connected in parallel between the pretreatment module and the mixed disinfection tank. The mixed disinfection tank is used to mix the seawater treated by the pre-dilution module and the pretreated seawater, and perform sterilization and disinfection. An inlet is provided on the side wall of the upper part of the mixed disinfection tank, and an outlet is provided on the side wall of the lower part of the mixed disinfection tank. An annular groove is fixed on the inner wall of the tank body of the mixed disinfection tank. The annular groove divides the inner part of the tank into a connected upper space and a lower space. A spoiler is fixed in the annular groove, and a frustum-shaped overflow weir is fixed on the inner side of the annular groove. The inlet is communicated with the annular groove. An inverted frustum-shaped guide plate is fixed on the inner wall of the overflow weir. An installation seat is provided on the lower wall inside the tank body of the mixed disinfection tank. A support rod is fixed on the installation seat. A buffer cone is fixed at the top of the support rod. The guide plate faces the buffer cone. A number of ultraviolet lamp columns evenly distributed in the circumferential direction are also provided on the installation seat. A number of layers of flow stabilizing discs are fixed on the support rod. The ultraviolet lamp columns pass through the flow stabilizing discs and approach the bottom of the annular groove.

2. The anti-fouling device for reverse osmosis membrane in seawater desalination according to claim 1, wherein: A sealing turntable is fixed at the bottom of the tank body of the mixed disinfection tank. The installation seat is fixed on the sealing turntable. An auxiliary handle is fixed on the topmost flow stabilizing disc. The bottom of the ultraviolet lamp column is threadedly connected to the installation seat. A maintenance door is provided on the bottom of the annular groove.

3. The anti-fouling device for reverse osmosis membranes in seawater desalination according to claim 2, characterized in that: A lithium battery is provided inside the ultraviolet lamp column, and a magnetic charging port is provided at the top of the ultraviolet lamp column.

4. The anti-fouling device for reverse osmosis membranes in seawater desalination according to claim 1, characterized in that: A water inlet pipe is fixed on the inlet. A spoiler paddle is provided inside the water inlet pipe. The water inlet pipe is connected to two water supply pipes. The first water supply pipe is connected to the pre-dilution module, and the second water supply pipe is connected to the pretreatment module.

5. The anti-fouling device for reverse osmosis membrane in seawater desalination according to claim 4, wherein: Flow regulating valves are provided on both of the two water supply pipes. A thermometer is suspended downward from the tank door at the top of the mixed disinfection tank. The thermometer is immersed in water to keep the water temperature in the tank at 25 - 30 degrees.

6. The anti-pollution device for reverse osmosis membranes in seawater desalination according to claim 1, characterized in that: A water outlet pipe is fixed on the outlet. An anti-vortex ring is fixed inside the water outlet pipe. A filter box is fixedly connected to the water outlet pipe. The filter box is connected to the post-dilution module.

7. The anti-pollution device for reverse osmosis membranes in seawater desalination according to claim 6, characterized in that: A detachable sealing cover is provided on the filter box. A sealing frame is fixed on the inner wall of the filter box. A sealing groove is provided on the sealing frame. A filter element frame is inserted into the sealing groove. A filter element is fixed on the filter element frame. A sealing strip matching the sealing groove is fixed on the inner wall of the sealing cover.

8. The anti-fouling device for reverse osmosis membrane in seawater desalination according to claim 1, characterized in that: The pretreatment module includes a clarification tank, a sand filter, a security filter and a reservoir connected in sequence. The reservoir is connected to the pre-dilution module and the mixed disinfection tank respectively through a circulation pump and a water supply pipe to provide pretreated normal-temperature seawater.

9. The anti-fouling device for reverse osmosis membranes in seawater desalination according to claim 1, characterized in that: The pre - desalination module includes an evaporation pond and a heating device. A fresh - water collection device is arranged above the evaporation pond. The heating device includes a solar collector panel, a heat - exchange pipe and a medium pump, which form a loop. And part of the heat - exchange pipes are arranged in the evaporation pond to raise the temperature of the seawater in the evaporation pond. The evaporation pond is connected to the mixing and disinfection tank through a circulation pump and a water supply pipe. The evaporation pond takes in water from the lower side and discharges water from the upper side to supply the mixing and disinfection tank with high - temperature seawater after part of the water has evaporated.

10. The anti-fouling device for reverse osmosis membranes in seawater desalination according to claim 1, characterized in that: The post - desalination module includes a nanofiltration membrane module, a reverse - osmosis membrane module and an energy recovery device. The mixing and disinfection tank is connected to the nanofiltration membrane module through a booster pump and a pipeline. The energy recovery device is arranged at the wastewater outlet ends of the nanofiltration membrane module and the reverse - osmosis membrane module.

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