Plate-type seawater desalination device based on novel plates and structure optimization
The plate-type seawater desalination unit, manufactured using stainless steel materials and welding processes, combined with a negative pressure environment and optimized flow channel design, solves the problems of large weight, high cost, and difficult maintenance of existing units, achieving efficient and easy-to-maintain seawater desalination.
Patent Information
- Application Number
- CN202511794294.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-02
- Publication Date
- 2026-01-20
AI Technical Summary
Existing plate-type seawater desalination plants suffer from problems such as bulky structure, high cost, low heat exchange efficiency, inconvenient maintenance, and poor media isolation, making it difficult to meet the actual needs of ships and offshore facilities.
The evaporation and condensation chamber and front cover are manufactured using stainless steel materials and welding processes. Combined with a negative pressure environment and optimized plate flow channel design, a lightweight, highly reliable, and easy-to-maintain seawater desalination unit is achieved.
It reduces production costs and weight, improves heat exchange efficiency and ease of maintenance, adapts to usage scenarios with limited space and variable operating conditions on ships, avoids media leakage, and achieves efficient seawater desalination.
Smart Images
Figure CN121361856A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of seawater desalination, in particular to a plate type seawater evaporation desalination device for ships or offshore facilities. BACKGROUND
[0002] The global freshwater resource shortage problem is becoming increasingly serious. Ships and offshore facilities are far away from land, and the supply of fresh water depends on transportation, which is costly and limited by shipping routes. Seawater desalination has become a core approach for them to obtain fresh water. Among various seawater desalination technologies, multi-effect evaporation plate type seawater desalination devices have become the mainstream choice in the field of ships due to their compact structure, high heat transfer efficiency, and relatively low energy consumption. Such devices usually use the waste heat of the cylinder jacket water of the ship's main engine as the heat source, heat the seawater through the principle of plate heat exchange to make it evaporate, and then condense the steam to produce fresh water, which can effectively reduce the energy consumption of the ship and meet the development needs of green shipping.
[0003] However, the existing plate type seawater desalination device still has many defects in actual application, which restricts its performance improvement and promotion. Firstly, the structure is heavy and the cost is high. The traditional evaporation and condensation cabin and front cover plate are usually made by casting process such as cast copper and cast aluminum or large-scale machining, which not only requires investment in expensive mold fees and long production cycle, but also has problems such as low material utilization rate and large weight of finished products. In addition, casting defects such as sand holes and pores are easy to occur, which affects the sealing reliability and service life of the equipment. Secondly, the heat transfer efficiency and operation convenience are insufficient. The flow channel of the traditional plate is usually simple corrugated or point-shaped protrusion, which is easy to form fluid dead zones and short circuits, leading to salt crystallization and blockage of the flow channel, and uneven distribution of liquid film, low heat and mass transfer efficiency. At the same time, the plate relies on the complex support structure inside the cabin for fixation, the front cover plate is thick and heavy, and the disassembly is cumbersome. The operation is difficult, time-consuming and laborious when cleaning and replacing the plate, which seriously affects the maintenance efficiency of the equipment. Thirdly, the medium isolation and working condition adaptability are poor. The sealing structure design of some devices is not reasonable, which is easy to cause the problem of leakage of hot medium and seawater, and the overall structure lacks flexibility, which makes it difficult to adjust the production capacity according to the demand of fresh water of the ship, and cannot well adapt to the limited space and variable working conditions of the ship.
[0004] In summary, there is still a lot of room for improvement in the structure design, cost control, heat transfer efficiency and operation convenience of the existing plate type seawater desalination device, and a new type of device with light weight, low cost, high efficiency and easy maintenance is urgently needed to meet the actual use requirements of ships and offshore facilities. SUMMARY
[0005] The purpose of the present application is to overcome the defects in the prior art and provide a plate type seawater desalination device based on new type of plate and structural optimization.
[0006] To achieve the above-mentioned purpose, the technical solution of the present application is as follows: The application discloses a plate type seawater desalination device based on a novel plate and structure optimization, which comprises an evaporation and condensation cabin, a front cover plate and a plate group, wherein the evaporation and condensation cabin is in a barrel type structure with an open end, the open end is provided with the front cover plate, a sealed cavity is formed in the evaporation and condensation cabin, the sealed cavity is provided with the plate group, and the plate group constitutes a plate heat exchanger arranged in the evaporation and condensation cabin; at least one plate heat exchanger is arranged in the sealed cavity. The plate heat exchanger is fixedly arranged on the front cover plate, the front cover plate is a side end plate of the plate heat exchanger, and the front cover plate is provided with a medium interface in communication with an internal flow channel of the plate heat exchanger. A relative negative pressure environment is created in the evaporation and condensation cabin, the plate heat exchanger comprises a heat medium loop and a seawater loop, the heat medium loop is a closed loop at the plate heat exchanger, the seawater loop is an open loop at the plate heat exchanger, a high point end of the seawater loop is communicated with the negative pressure environment of the evaporation and condensation cabin, and the seawater loop is driven under the negative pressure environment, so that the seawater is partially evaporated and condensed and gathered in the evaporation and condensation cabin.
[0007] Further, the evaporation and condensation cabin comprises a cylindrical barrel and a disc-shaped head welded to one end of the barrel, the barrel and the disc-shaped head are both processed from stainless steel plates, the other end of the barrel is provided with a flange ring, and the evaporation and condensation cabin is sealed and connected to the front cover plate through the flange ring.
[0008] Further, the front cover plate is a plate-shaped structure made of stainless steel through turning and milling, and the front cover plate is further provided with a thermometer and a vacuum pressure gauge.
[0009] Further, the plate group is fixedly arranged on the front cover plate through a fixing mechanism, the fixing mechanism comprises a center guide rod, a pressing screw rod and a pressing plate, predetermined positions of the front cover plate are processed with a light hole and a threaded hole matched with the center guide rod and the pressing screw rod, and the plate heat exchanger comprises the following assembly steps. S1: horizontally placing the front cover plate, inserting the center guide rod into the light hole to be vertically fixed, and screwing the pressing screw rod into the threaded hole; S2: during assembly, sequentially stacking each heat exchange plate and the end pressing plate of the plate group on the center guide rod to ensure the centering accuracy; S3: rotating the pressing nut on the pressing screw rod arranged on the front cover plate, and pressing the pressing nut against the pressing plate, so that the whole plate group is pressed and fixed on the front cover plate.
[0010] Further, the heat exchange plate of the plate heat exchanger is a corrugated plate structure, the heat exchange plate is provided with medium passage holes at four corners, the middle part of the heat exchange plate is provided with V-shaped heat exchange corrugated grooves, the heat exchange corrugated grooves are arranged in sequence in the transverse direction, adjacent heat exchange corrugated grooves form secondary branch flow channels, and the lower end of the heat exchange corrugated grooves forms a transversely arranged main flow channel.
[0011] Further, the main flow channel and the secondary branch flow channel are both designed in an inverted trapezoidal structure, the groove bottom width of the main flow channel is 10.5 mm, the groove bottom depth is 2.5 mm, and the opening angle of the waist on both sides of the main flow channel is 72°; the groove bottom depth of the secondary branch flow channel is 2.5 mm, the center distance between adjacent two secondary branch flow channels is 10 mm, and the opening angle of the waist on both sides of the secondary branch flow channel is 81°; and the thickness of the heat exchange plate is 0.6 mm.
[0012] Further, the first side surface of the heat exchange plate is provided with a first sealing ring and a second sealing ring, the heat source inlet and the heat source outlet of the heat medium circuit are arranged in the range surrounded by the first sealing ring, and the seawater inlet and the seawater evaporation side inlet of the seawater circuit are arranged in the second sealing ring.
[0013] Further, the second side surface of the heat exchange plate is provided with a third sealing ring, a fourth sealing ring and a fifth sealing ring, the third sealing ring is open upward toward the upper end side, the seawater inlet and the seawater evaporation side inlet are located in the range surrounded by the third sealing ring; the heat source inlet and the heat source outlet are arranged in the fourth sealing ring respectively, the fifth sealing ring is arranged on the inner side of the third sealing ring, and the seawater inlet is located in the fifth sealing ring.
[0014] Further, the diameter of the seawater evaporation side inlet is 5-10 mm.
[0015] The advantages and beneficial effects of the present application are as follows: 1. Cost reduction, weight reduction and reliability: The evaporation condensation cabin body adopts stainless steel roll welding instead of traditional casting parts, and the front cover plate uses stainless steel machining parts instead of cast copper parts, which saves expensive mold fees and shortens the production cycle, significantly reducing material and processing costs; the stainless steel structure is lighter than cast copper and cast iron parts, which meets the load demand of the ship, and the welding structure avoids casting defects, improving the long-term reliability of the equipment.
[0016] 2. Efficient heat exchange and easy maintenance: The "main-secondary" flow channels of the heat exchange plate are designed in an inverted trapezoidal structure, which cooperates with the negative pressure environment to realize uniform film formation and efficient evaporation of seawater, and improves the heat and mass transfer efficiency; the plate group is fixed through the center guide rod and the compression screw rod, and only the screw rod needs to be loosened for disassembly, so that cleaning and plate replacement are convenient, reducing maintenance time and technical difficulty.
[0017] 3. Adapt to the scene to prevent leakage: stainless steel material resistant to seawater corrosion, multiple sealing rings to isolate heat medium and seawater circuit, to avoid medium leakage; compact structure, can increase or decrease plate heat exchanger group as needed, adapt to the scene of limited space and variable fresh water demand of the ship, negative pressure condition can also reduce the boiling point of seawater, save heat source energy consumption. BRIEF DESCRIPTION OF DRAWINGS
[0018] Figure 1 is a three view of a plate type seawater desalination device based on a new type of plate and structure optimization of the application; Figure 2 is a structural schematic diagram of the heat exchange plate in the application; Figure 3 is a structural schematic diagram of the first side of the heat exchange plate in the application; Figure 4 is a structural schematic diagram of the second side of the heat exchange plate in the application; In the figure: 1, evaporation and condensation cabin; 2, front cover plate; 3, plate group; 4, plate heat exchanger; 5, medium interface; 6, cylinder; 7, dish head; 8, flange ring; 9, thermometer; 10, vacuum pressure gauge; 11, compression screw; 12, compression plate; 13, medium passage hole; 14, heat exchange corrugated groove; 15, secondary branch flow channel; 16, main flow channel; 17, first sealing ring; 18, second sealing ring; 19, heat source inlet; 20, heat source outlet; 21, seawater inlet; 22, seawater evaporation side inlet; 23, third sealing ring; 24, fourth sealing ring; 25, fifth sealing ring; 26, upper opening. DETAILED DESCRIPTION
[0019] The specific embodiments of the application will be further described below in combination with examples. The following examples are only used to more clearly illustrate the technical solutions of the application, and cannot be used to limit the protection scope of the application.
[0020] A plate type seawater desalination device based on a new type of plate and structure optimization of the application, around the seawater desalination demand of the ship or offshore facility, taking "lightweight structure, high efficiency of heat exchange, simple operation and maintenance" as the core, through the improved design of evaporation and condensation cabin 1, front cover plate 2, plate group 3 and fixing mechanism, combined with negative pressure environment and falling film evaporation principle, a set of plate type seawater desalination device with less space occupation and reliable use is constructed, specifically: The whole device takes the evaporation and condensation cabin 1 as the core sealed space, cooperates with the front cover plate 2 to realize sealing and medium access, and internally sets the plate heat exchanger 4 composed of the plate group 3, and the plate heat exchanger 4 is fixed on the front cover plate 2 through the fixing mechanism, and seawater evaporation and condensation are driven by using the negative pressure environment, and finally the desalination process is completed. Among them, the evaporation and condensation cabin 1 adopts a barrel-shaped structure formed by rolling and welding of stainless steel plates, one end is open and sealed and connected with the front cover plate 2 through a flange ring 8, and the other end is welded with a standard butterfly head, abandoning the traditional casting process, not only reducing the mold cost and production cycle, but also avoiding defects such as sand holes and pores of castings, and at the same time, the stainless steel material (such as 316L) has excellent seawater corrosion resistance, which is suitable for the harsh marine environment. The front cover plate 2 is used as one side end plate of the plate heat exchanger 4, which is made of stainless steel plate through turning and milling processing, not only replacing the traditional thick cast copper piece to reduce weight and cost, but also integrating the medium interface 5 (used for accessing hot medium, seawater and leading out concentrated brine and fresh water) connected with the internal flow channel of the plate heat exchanger 4, and installing the thermometer 9 and the vacuum pressure gauge 10, and real-time monitoring the temperature and negative pressure state in the cabin, providing basis for equipment operation parameter regulation.
[0021] The plate heat exchanger 4 is the core functional component for realizing seawater desalination, and at least one group can be set in the device according to the fresh water yield demand, such as Figure 1 As shown in the embodiment, two groups of plate heat exchangers 4 are arranged in the evaporation and condensation cabin 1, and are stably assembled on the front cover plate 2 through the fixing mechanism. The fixing mechanism is composed of a center guide rod, a compression screw rod 11, a compression plate 12 and a compression nut, and when assembled, the front cover plate 2 is first placed horizontally, the center guide rod is inserted vertically and fixed in the pre-designed light hole, and the compression screw rod 11 is installed in the threaded hole; then the heat exchange plates of the plate group 3 and the end compression plate 12 are sequentially inserted into the center guide rod, the centering accuracy of the plates is ensured by the guide rod, and the assembly deviation is avoided to affect the sealing and heat exchange; finally, the compression nut is rotated to push the compression plate 12, and the whole plate group 3 is tightly compressed on the front cover plate 2 to form a reliable seal. This fixing method abandons the traditional complex support structure, and when disassembled, the plate group 3 can be pulled out only by loosening the compression screw rod 11, which greatly reduces the operation difficulty and time cost of cleaning and replacing the plates.
[0022] The heat exchange plate is the core unit of the plate heat exchanger 4, adopts a corrugated plate structure and is finely designed for flow channel and sealing to adapt to the falling film evaporation principle. As Figure 2As shown, the plate is provided with medium passage holes 13 at four corners for realizing the inlet and outlet of heat medium and seawater and flow conversion; a V-shaped heat exchange corrugated groove 14 is pressed in the middle part, the groove bodies are arranged in sequence in the transverse direction, adjacent corrugated grooves form secondary branch flow channels 15, the lower end of the corrugated groove forms a transverse main flow channel 16, the main flow channel 16 is communicated with the lower end of each secondary branch flow channel 15, forming a flow channel system of "main-secondary" cooperation. In order to optimize the performance of the flow channel, the main flow channel 16 and the secondary branch flow channel 15 are designed as inverted trapezoidal structures, wherein the main flow channel 16 has a groove bottom width of 10.5 mm, a depth of 2.5 mm, and an opening angle of 72° at both sides of the waist, the secondary branch flow channel 15 has a groove bottom depth of 2.5 mm, a center distance between adjacent grooves of 10 mm, and an opening angle of 81° at the waist, and the plate with a thickness of 0.6 mm can not only ensure the structural strength, but also reduce the heat transfer resistance. This flow channel design can form a uniform liquid film during the flow of seawater, increase the heat transfer area, reduce the steam flow resistance, improve the heat and mass transfer efficiency, and avoid the problems of scaling and uneven liquid film distribution in the dead zone of the traditional flow channel.
[0023] In the design of sealing and flow channel isolation, the heat exchange plate realizes the complete independence of the heat medium loop and the seawater loop through multiple sealing rings to avoid medium leakage. For example Figure 3 , 4As shown, the first side of the plate is provided with a first sealing ring 17 and a second sealing ring 18, and the heat source inlet 19 and outlet of the heat medium circuit are defined within the range surrounded by the first sealing ring 17, and the seawater inlet 21 and seawater evaporation side inlet 22 of the seawater circuit are located within the second sealing ring 18; the second side of the plate is correspondingly provided with a third sealing ring 23, a fourth sealing ring 24 and a fifth sealing ring 25, wherein the third sealing ring 23 is designed as an opening towards the upper end side, the seawater inlet 21 and the seawater evaporation side inlet 22 (diameter 5-10mm, suitable for steam outlet requirement under negative pressure) are located within the range of the third sealing ring 23, the heat source inlet 19 and outlet are independently arranged within the fourth sealing ring 24, and the fifth sealing ring 25 is located inside the third sealing ring 23 and wraps the seawater inlet 21, further strengthening the sealing isolation of the seawater flow channel; in actual use, the seawater inlet 21 is blocked by the second sealing ring 18 on the first side and cannot enter the first sealing ring 17, and then the seawater passes through the heat exchange plate to the second side thereof, on the second side, the seawater inlet 21 is blocked by the fifth sealing ring 25 and cannot enter the range of the third sealing ring 23, the second side of the heat exchange plate is the evaporation side, and in use, when the liquid level of the seawater at the second sealing ring 18 on the first side reaches the seawater evaporation side inlet 22, the seawater can pass through the seawater evaporation side inlet 22 to enter the evaporation side of the second side for evaporation, under the driving of negative pressure, the seawater passing through the seawater evaporation side inlet 22 evaporates on the evaporation side, and the evaporated seawater condenses into water in the evaporation and condensation cabin 1 and is sent out from the medium interface 5. The cooperative action of multiple sealing rings ensures that the heat medium circuit forms a closed loop in the plate heat exchanger 4 - the heat medium such as the main cylinder sleeve water enters from the heat source inlet 19, flows through the flow channel for heat exchange, and then returns from the heat source outlet 20, without contacting seawater throughout the process; and the seawater circuit is an open loop, seawater flows into from the seawater inlet 21, forms a liquid film along the main flow channel 16 and the secondary branch flow channel 15, and under the driving of the relative negative pressure environment of the evaporation and condensation cabin 1, part of the seawater is heated and evaporated, the steam enters the evaporation side through the seawater evaporation side inlet 22, the concentrated brine that has not evaporated is discharged along the flow channel, the steam entering the cabin is condensed to form fresh water and is collected, and finally seawater desalination is completed.
[0024] The technical scheme of the present application combines structure material innovation, flow channel optimization, sealing isolation design and negative pressure working condition, solves the pain points of traditional plate seawater desalination device such as large weight, high cost and difficult maintenance, and realizes efficient and stable seawater desalination through the deep integration of falling film evaporation principle and plate structure, which is completely suitable for limited space and complex working condition of marine application scenarios such as ships.
[0025] The above is only the preferred embodiment of the present application, and it should be pointed out that for ordinary skilled persons in the art, some improvements and refinements can be made without departing from the technical principles of the present application, and these improvements and refinements should also be regarded as the protection scope of the present application.
Claims
1. A plate type seawater desalination device based on a new type of plate and structure optimization, characterized in that, The utility model provides a kind of evaporative condensation cabin, front cover plate, sheet group, the evaporative condensation cabin is barrel type structure with one end opening, its open end is provided with front cover plate, so that the sealed cavity is formed in evaporative condensation cabin, the sealed cavity is provided with sheet group, and the sheet group constitutes the plate heat exchanger arranged in evaporative condensation cabin;At least one set of plate heat exchanger is provided in the sealed cavity; The plate heat exchanger is fixedly arranged on the front cover plate, and the front cover plate is one side end plate of the plate heat exchanger, and the front cover plate is provided with a medium interface in communication with the internal flow channel of the plate heat exchanger; A relative negative pressure environment is created in the evaporative condensation cabin;The plate heat exchanger includes a thermal medium circuit and a seawater circuit, and the thermal medium circuit is a closed loop at the plate heat exchanger;The seawater circuit is an open loop at the plate heat exchanger, and the high point end of the seawater circuit is in communication with the negative pressure environment of the evaporative condensation cabin, so that the seawater circuit is driven under the negative pressure environment, and the seawater is partially evaporated and condensed in the evaporative condensation cabin.
2. A plate and frame seawater desalination device based on a novel plate and structural optimization according to claim 1, characterized in that, The evaporative condensation cabin includes a cylindrical barrel and a disc-shaped head welded to one end of the barrel;The barrel and the disc-shaped head are both made of stainless steel sheet, and the other end of the barrel is provided with a flange ring, and the evaporative condensation cabin is sealed and connected to the front cover plate through the flange ring.
3. A plate and frame seawater desalination device based on a novel plate and structural optimization according to claim 1, characterized in that, The front cover plate is made of stainless steel and has a plate-shaped structure formed by turning and milling, and the front cover plate is further provided with a thermometer and a vacuum pressure gauge.
4. A plate and frame seawater desalination device based on a novel plate and structural optimization according to claim 1, characterized in that, The sheet group is fixedly arranged on the front cover plate by a fixing mechanism, and the fixing mechanism includes a center guide rod, a compression screw rod and a compression plate, and the predetermined position of the front cover plate is processed with a light hole and a threaded hole matched with the center guide rod and the compression screw rod, and the plate heat exchanger includes the following assembly steps: S1: horizontally place the front cover plate, insert the center guide rod into the light hole to make it vertically fixed, and insert the compression screw rod into the threaded hole; S2: during assembly, sequentially stack each heat exchange sheet and the compression plate at the end of the sheet group on the center guide rod to ensure the centering accuracy; S3: rotate the compression nut on the compression screw rod arranged on the front cover plate to compress and fix the entire sheet group on the front cover plate by the compression nut pressing on the compression plate.
5. A plate and frame seawater desalination device based on a novel plate and structural optimization according to claim 1, characterized in that, The heat exchange sheet of the plate heat exchanger is a corrugated sheet structure, the heat exchange sheet is provided with a medium passage hole at each corner, the middle part of the heat exchange sheet is provided with a V-shaped heat exchange corrugated groove, the heat exchange corrugated grooves are arranged in sequence in a horizontal direction, adjacent heat exchange corrugated grooves form secondary branch flow channels, and the lower end of the heat exchange corrugated groove forms a horizontally arranged main flow channel, which is in communication with the lower end of each secondary branch flow channel.
6. A plate and frame seawater desalination device based on a novel plate and structural optimization according to claim 5, characterized in that, The main flow channel and the secondary branch flow channel are both designed in an inverted trapezoidal structure, the groove bottom width of the main flow channel is 10.5 mm, the groove bottom depth is 2.5 mm, and the opening angle of the waist on both sides of the main flow channel is 72°;The groove bottom depth of the secondary branch flow channel is 2.5 mm, the center distance between adjacent two secondary branch flow channels is 10 mm, and the opening angle of the waist on both sides of the secondary branch flow channel is 81°, and the thickness of the heat exchange sheet is 0.6 mm.
7. A plate and frame seawater desalination device based on a novel plate and structural optimization according to claim 5, characterized in that, The first side of the heat exchange plate is provided with a first sealing ring and a second sealing ring, the heat source inlet and the heat source outlet of the heat medium circuit are arranged in the range surrounded by the first sealing ring, and the seawater inlet and the seawater evaporation side inlet of the seawater circuit are arranged in the second sealing ring.
8. A plate and frame seawater desalination device based on a novel plate and structural optimization according to claim 7, characterized in that, The second side of the heat exchange plate is provided with a third sealing ring, a fourth sealing ring and a fifth sealing ring, the third sealing ring is open upward at the upper end side, the seawater inlet and the seawater evaporation side inlet are located in the range surrounded by the third sealing ring, the heat source inlet and the heat source outlet are arranged in the fourth sealing ring respectively, the fifth sealing ring is arranged in the inner side of the third sealing ring, and the seawater inlet is located in the fifth sealing ring.
9. A plate and frame seawater desalination device based on a novel plate and structural optimization according to claim 7, characterized in that, The diameter of the seawater evaporation side inlet is 5-10 mm.