CN110203988A - A kind of vacuum system and seawater desalination system - Google Patents

Abstract

The invention provides a vacuum system, including a vacuum maintenance device, the device adopts a sealed structure to maintain the internal pressure of the device, and uses the Venturi principle to evacuate the device to reduce the internal pressure of the device and reduce the boiling point of seawater when it evaporates; the Venturi tube is placed on At the seawater outlet, part of the seawater is treated and enters the tank for desalination, and the other part that accounts for the majority is discharged directly. During the discharge process, it passes through the Venturi tube. When cold water flows, the cross section suddenly shrinks and the flow velocity increases. The pressure difference takes away the air in the tank and maintains a low pressure inside the tank. The invention drains the waste water from the condenser to the Venturi tube and then leads it out. One end of the Venturi tube communicates with the main tank, and the Venturi principle is used to extract air to maintain the vacuum required for low-temperature distillation and effectively reduce energy consumption. This design cleverly combines the condensing part and the vacuuming part, which simplifies the equipment and does not require an additional vacuum pump for vacuuming, which improves the comprehensive performance of the equipment and significantly reduces the energy consumption.

Description

A vacuum system and seawater desalination system

technical field

The invention relates to the fields of loop heat pipes, solar energy and seawater desalination, in particular to a loop heat pipe utilizing solar energy and a seawater desalination system thereof.

Background technique

Heat pipe technology is a heat transfer element called "heat pipe" invented by George Grover of Los Alamos National Laboratory in the United States in 1963. It makes full use of the principle of heat conduction and phase change medium. The rapid heat transfer properties of the heat pipe quickly transfer the heat of the heating object to the heat source, and its thermal conductivity exceeds that of any known metal.

Heat pipe technology was widely used in aerospace, military and other industries before. Since it was introduced into the radiator manufacturing industry, people have changed the traditional radiator design ideas and got rid of the single heat dissipation mode that only relies on high air volume motors to obtain better heat dissipation. The use of heat pipe technology enables the radiator to obtain a satisfactory heat exchange effect, opening up a new world in the heat dissipation industry. At present, heat pipes are widely used in various heat exchange devices, including the fields of solar energy and seawater desalination, such as the utilization of solar energy.

There are more than 10,000 islands in China, but most of them are uninhabitable due to lack of fresh water. There are less than 500 permanent residents, which restricts the development and defense functions of the islands. The National Development and Reform Commission and the State Oceanic Administration jointly issued the "Island Seawater Desalination Project Implementation Plan" at the end of 2017, proposing that by 2020, the water problem of island residents will be effectively alleviated, the living environment will be improved, and seawater desalination will become the main water supply method for islands with severe water shortages. One is to basically meet the island's ever-increasing living and production water needs.

In response to the above problems, we propose a method based on the mechanism of phase change enhanced heat transfer, using loop heat pipe technology, plate CPL capillary pump technology, new fin-type turbulent evaporator and integrated VC plate-fin condenser to achieve low temperature and low energy. It is a tabletop-sized solar desalination system with solar energy, and innovatively adopts the venturi vacuum pumping method, which simplifies the equipment and greatly reduces energy consumption. The system adopts a wind-solar complementary energy supply system, which is suitable for areas with complex conditions where electricity is scarce and freshwater resources are scarce. Finally, connecting the host computer operating platform to the embedded chip control node switch and collecting device node sensor data also significantly reduces the difficulty of operation, realizing unattended, remote control and fully automated operation of equipment.

Contents of the invention

The invention provides a new type of seawater desalination system, which utilizes the combination of solar energy and loop heat pipes, utilizes the performance of the anti-gravity heat pipes and the expanded heat exchange area, thereby solving the technical problems arising above.

In order to achieve the above object, the technical scheme of the present invention is as follows:

A seawater desalination system, the system includes an evaporation system, a condensation system and a fresh water collection system, seawater is evaporated in the evaporation system to generate steam, and then the steam is condensed in the condensation system to become fresh water, and then the fresh water is collected through the fresh water collection system,

The evaporation system includes a solar collector and a loop heat pipe. The loop heat pipe absorbs solar energy at the evaporation end, and then exchanges heat with seawater at the condensation end to evaporate the seawater;

The condensing system includes a condenser, and the condenser includes a cold water inlet, a cold water outlet, a uniform temperature plate, and a plate-type condensing part, and the plate-type condensing part includes a plurality of parallel isolated horizontal plates, forming a The cold water flow channel is provided with a spoiler in the cold water flow channel, and the spoiler is a curved plate. The spoiler is arranged in the middle of the cold water flow channel and has a certain distance from the isolation horizontal plate. The extending direction of the spoiler is in line with the The isolation horizontal plates are parallel; one end of the vapor chamber is arranged on the upper and lower parts of the plate-type condensing part, and the other end of the vapor chamber is provided with fins away from the plate-type condensing part; a closed cavity is arranged inside the chamber, and the cavity A capillary structure is arranged on the inner side; the cold water inlet and the cold water outlet are respectively arranged on the opposite sides of the plate-type condensing part;

The fresh water collection system includes an upper water tray and a lower water tray. The upper water tray is located at the lower part of the condenser and at the upper part of the lower water tray. There is a hole in the middle of the upper water tray. The outermost end is provided with an upward The vertical part, connected with the vertical part is a horizontal part, and an upward inclined part extending inwardly along the horizontal part; the horizontal part is provided with holes for fresh water to flow into the lower water tray; the lower water the tray includes a hole in the middle that connects to a fresh water collection tank;

The seawater desalination system also includes a vacuum system, and the condenser, the upper water receiving tray, the lower water receiving tray and the condensation end of the loop heat pipe are arranged in the vacuum system.

The condenser, the upper water tray, the lower water tray and the condensation end of the loop heat pipe are arranged sequentially from top to bottom.

Preferably, it also includes a seawater circulation spray system, the seawater circulation spray system is arranged in a vacuum system, and the seawater circulation spray system includes a circulation spray pump, an atomizing spray head and a circulation pipeline, and the atomization spray system The shower head is set on the upper part of the condensation end; the circulation spray pump pumps the seawater in the vacuum system into the atomization shower head, and then sprays to the condensation end.

Preferably, the evaporating end is a plate structure, the solar heat collector includes a solar heat collecting plate, and the upper surface of the evaporating end is attached to the lower surface of the solar heat collecting plate.

Preferably, the evaporating end is a plate structure, and the upper surface of the evaporating end is a solar heat collecting plate.

Preferably, the condensing end is a tube-sheet heat exchange structure, including an inlet header, an outlet header, an inlet heat exchange tube, an outlet heat exchange tube and a plate group, the inlet header is connected to the inlet heat exchange tube, and the The heat pipe is connected to the corresponding plate group. The plate group is a heat exchange channel formed by combining two plates. The plate group is connected to the outlet heat exchange tube, and the outlet heat exchange tube is connected to the outlet header. The steam from the evaporation end passes through The inlet header enters the inlet heat exchange tube, then enters the plate group through the inlet heat exchange tube, then enters the outlet heat exchange tube through the plate group, and then discharges through the outlet header. The inlet heat exchange tube, outlet heat exchange tube and plate group are the main parts of heat exchange, and preferably, the inlet header and outlet header also participate in heat exchange. The condensing end is soaked in seawater or the seawater is sprayed to the condensing end by a spraying device for heat exchange.

Preferably, there are multiple inlet heat exchange tubes, and each inlet heat exchange tube corresponds to a plate group. The plurality of plate packs are parallel spaced apart structures. Preferably, there are multiple outlet heat exchange tubes, and each outlet heat exchange tube corresponds to a plate group.

Preferably, a vacuum system is also included, the vacuum system includes a vacuum tank, and the condenser, the upper water receiving tray, the lower water receiving tray, and the condensing end are arranged in the vacuum tank.

Preferably, a seawater concentration detection device is provided in the tank for detecting the concentration of seawater, and the controller automatically controls the discharge of seawater according to the detected concentration of seawater.

Compared with the prior art, the present invention has the following advantages:

1) The present invention provides a new type of seawater desalination system, which combines solar energy and loop heat pipes, and utilizes the performance of loop heat pipes to improve the utilization of seawater desalination.

2) The present invention has developed a new type of fresh water collection device. By setting the upper and lower water receiving trays, the fast collection of fresh water can be realized and the waste of fresh water can be avoided.

3) Combining CPL technology with seawater desalination. According to the principle of phase transformation heat transfer, the CPL capillary pump, which can transfer a large amount of heat over a long distance under a small temperature difference, is innovatively combined with seawater desalination equipment, and the plate design is adopted to make the heat transfer efficiency higher than that of the traditional convective heat transfer mode. Increased by about 4 times, greatly improving heat transfer efficiency.

4) Condenser and falling film evaporator with innovative structure. The condenser adopts a chip structure design, combined with a uniform temperature plate and fins, and a sintered mesh structure is attached to the VC cavity to realize phase conversion heat, so that the heat can be spread quickly and evenly in the plane, and the heat can be greatly increased through the fin structure. The contact area improves the heat transfer efficiency, which increases the heat transfer efficiency by about 15% compared with the traditional fin structure. In addition, self-designed new fin-type turbulence evaporator, the multi-plate structure is arranged in parallel, which greatly increases the contact area with the atomized spray seawater, and the heat transfer efficiency is increased by 20% according to the actual measurement.

5) Venturi tube realizes vacuuming of waste water. The waste water from the condenser is drained to the Venturi tube and then exported. One end of the Venturi tube is connected to the main tank, and the venturi principle is used to extract the air to maintain the vacuum required for low-temperature distillation and effectively reduce energy consumption. This design cleverly combines the condensing part and the vacuuming part, which simplifies the equipment and does not require an additional vacuum pump for vacuuming, which improves the comprehensive performance of the equipment and significantly reduces the energy consumption.

6) The present invention adopts a new structure flow stabilizing device, through the square and the regular octagon, the angle formed by the sides of the square hole and the regular octagon hole is greater than or equal to 90 degrees, so that the fluid can fully flow through each Every position of the hole avoids or reduces the short circuit of the fluid flow. The invention separates the two-phase fluid into a liquid phase and a gas phase through a new structure of the flow stabilization device, divides the liquid phase into small liquid masses, and divides the gas phase into small bubbles, inhibits the backflow of the liquid phase, promotes the smooth flow of the gas phase, and stabilizes The effect of flow has the effect of reducing vibration and noise. Compared with the current stabilizing device in the prior art, the current stabilizing effect is further improved, and the manufacture is simple.

The invention has wide application prospects.

1) The product greatly reduces energy consumption and has a significant advantage in operating costs. The operating energy consumption of this equipment is about 9000 kilojoules per ton, which is about 1/4 of the operating energy consumption of the traditional multi-stage flash evaporation and multi-stage distillation modes. The energy saving advantage is significant, and it can save about 420,000 yuan per year compared with other seawater desalination methods.

2) The equipment covers an area of only 1.2㎡, which is one-fifth of the existing common seawater desalination device. At present, the seawater desalination equipment on the market is mainly large-scale and ultra-large-scale equipment with a daily output of 1,000 tons of fresh water, which cannot be applied to small places such as fishing boats and small islands. However, this equipment innovatively adopts new technology, which greatly reduces the occupied area and makes up for the gap in the market.

3) Use stable and clean energy. my country's islands are mainly distributed in the South China Sea. This area has long sunshine time and strong radiation, which is suitable for the development and promotion of solar seawater desalination devices. The application of solar clean energy is pollution-free, which is in line with the national environmental protection policy.

Benefit Analysis of Energy Saving and Emission Reduction of the Present Invention

1) In terms of device energy acquisition. The energy consumed by small seawater desalination devices mainly comes from solar energy. According to data, the average solar radiation intensity on the earth orbit is 1369W/m2, and the standard peak intensity at sea level is 1kW/m2. The radiation intensity in areas near the equator such as South my country Sea islands Larger, solar energy resources are very rich, compared with the consumption of increasingly scarce petroleum resources, this device uses solar energy to supplement energy and successfully realizes the effective use of environmentally friendly new energy.

2) In terms of fresh water production benefits and secondary pollution. The fresh water output of this device is 120 liters per day, equivalent to 240 bottles of drinking mineral water, which can supply about 50 adults for daily drinking. This not only saves the trouble of shipping fresh water affected by weather factors, but also saves about 512 tons per year Diesel fuel reduces carbon dioxide emissions by 810 million liters, perfectly realizing the effect of energy saving and emission reduction.

This device can also solve the problem of drinking fresh water for residents around the saline-alkali lake. Compared with the fresh water transported by vehicles that discharge a large amount of polluted exhaust along the way, this device can achieve zero-emission salt water desalination without secondary pollution, saving fuel resources and protecting the ecology It also effectively reduces the emission of harmful gases while improving the environment.

3) In terms of device operating efficiency. From the perspective of the mechanical structure of the device, the CPL capillary pump used in this device uses the principle of phase-change heat transfer. Compared with the existing convective heat transfer, the heat transfer efficiency is increased by about 4 times; the original design of the integrated VC plate-fin condenser, significantly The heat transfer contact surface area is greatly increased, and the heat transfer efficiency is increased by 15% compared with the traditional fin structure; the new heat sink type spoiler evaporator is selected, and the parallel arrangement greatly increases the heat transfer area, which increases the heat transfer efficiency by 20%. The increase of efficiency means the reduction of unit energy consumption. According to the effective calculation, the energy consumption per ton of water of this device is only 9000KJ, accounting for 62.5% of the energy consumption of the reverse osmosis desalination method and 20% of the energy consumption of the multi-effect distillation desalination method under the same conditions. 18% of the energy consumption of the multi-effect distillation desalination method, the energy saving effect is remarkable.

5) In terms of device control methods. From the point of view of the operation mode, the device is fully automatic operation, one-button start and stop, which eliminates the dependence on manual operation, and only needs to be maintained once a year, which greatly reduces labor energy consumption and saves time for control and maintenance. A variety of non-essential energy consumption generated by the device.

6) In terms of fresh water quality obtained by the device. The water produced by this device has been inspected by Weihai Quality Supervision Bureau and has reached the standard of drinking water. The energy expenditure required to obtain fresh water is reduced, and the obtained fresh water is of good quality without secondary purification, saving cost and energy consumption in the water purification process.

Description of drawings

Fig. 1 is a structural schematic diagram of the solar seawater desalination system of the present invention.

Fig. 2 is a view diagram of the structure of the fresh water condensing device of the present invention.

Fig. 3 is a bottom view of the vapor chamber in Fig. 2 .

Figure 4 is a schematic diagram of the internal structure of the plate-type condensing part in Figure 2

Figure 5-1 is a structural diagram of the solar evaporation system.

Figure 5-2 is a structural diagram of solar energy combined with evaporation system.

Figure 6 is a schematic diagram of the working principle of the loop heat pipe.

Figure 7-1 is a schematic diagram of the structure of a heat pipe evaporator.

Figure 7-2 is a schematic diagram of A-A in Figure 7-1.

Figure 8-1 is a schematic diagram of the structure of the condensation end of the heat pipe.

Fig. 8-2 is a schematic diagram of the structure in different directions in Fig. 8 .

Fig. 9 is a schematic diagram of the vacuum pumping structure;

Fig. 10 is a schematic diagram of circulating spraying;

Fig. 11 is a schematic structural diagram of a fresh water collection system;

Fig. 12 is a schematic diagram of the cross-sectional structure of the partition device of the present invention;

Fig. 13 is a schematic diagram of another cross-sectional structure of the partition device of the present invention;

Figure 14 is a schematic diagram of the layout of the partition device in the riser of the present invention;

Fig. 15 is a cross-sectional schematic diagram of the arrangement of the partition device of the present invention in the riser.

Figure 16 Schematic diagram of the structure of the lower water tray;

Fig. 17 is a schematic diagram of the structure of the upper water tray.

The reference signs are as follows: 1 solar heat collecting plate, 2 loop heat pipe, 3 electric heating plate, 4 cold water inlet, 5 condenser, 6 water receiving tray, 7 spray head, 8 evaporator, 9 cold water outlet, 10 Venturi tube , 11 waste water outlet, 12 vacuum tank; 13 fresh water collection box, 14 steady flow device;

21 outer wall of upper cover plate, 22 steam channel, 23 capillary core, 24 liquid channel, 25 outer wall of base, 26 gasket, 27 steam collection box;

51 upper fin, 52 upper equal temperature plate, 521 cavity, 522 capillary structure, 523 fin, 53 cold water inlet, 54 cold water outlet, 55 plate type condensing part, 551 isolation horizontal plate, 552 spoiler, 56 lower equal temperature plate, 57 lower fins;

61 lower water tray, 611 hole, 62 upper water tray, 621 hole, 622 vertical part, 623 horizontal part, 624 inclined part

81 inlet pipe, 82 inlet header, 83 inlet heat exchange tube, 84 plate group, 85 outlet heat exchange tube, 86 outlet header, 87 outlet pipe, 88 fresh water collection pipe, 89 fresh water collection barrel, 90, partial seawater inlet, 91 centrifugal pump, 92 circulation spray pipe

Detailed ways

The specific embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings.

In this article, if there is no special explanation, when it comes to formulas, "/" means division, and "×" and "*" mean multiplication.

The specific embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings.

A seawater desalination system as shown in Figure 1, the seawater desalination system includes an evaporation system, a condensation system and a fresh water collection system, seawater is evaporated in the evaporation system to generate steam, and then the steam is condensed in the condensation system to become fresh water, and then fresh water Collect via freshwater collection system.

The evaporation system includes a solar heat collector 1 and a loop heat pipe 2. The loop heat pipe 2 absorbs solar energy at the evaporation end, and then exchanges heat with seawater at the condensation end 8 to evaporate the seawater;

The condensation system includes a condenser 5, and the condenser 5 condenses water vapor produced by evaporation of seawater;

The fresh water collecting system includes a water receiving tray, which is located at the lower part of the condenser 5, and is used to collect condensed water produced by condensation of the condenser;

The condenser 5, the water receiving tray and the condensation end of the loop heat pipe are arranged sequentially from top to bottom.

Preferably, the condensing system includes a condenser 5, the condenser 5 includes a cold water inlet 53, a cold water outlet 54, equal temperature plates 52, 56, a plate condensing part 55, and the plate condensing part 55 includes a plurality of parallel isolated A cross plate 551 and a cold water channel are formed between adjacent isolation transverse plates 551, and a spoiler 552 is arranged in the cold water channel, and the spoiler 552 is a curved plate, preferably in a V-shaped curved structure. The spoiler 552 is arranged in the cold water channel and has a certain distance from the isolation horizontal plate, and the extending direction of the spoiler 552 is parallel to the isolation horizontal plate; the uniform temperature plate includes an upper equal temperature plate 52 and a lower equal temperature plate 56 One end of the upper vapor chamber 52 is arranged on the upper part of the plate condensing part 55, one end of the lower vapor chamber 56 is arranged on the lower part of the plate condensing part, and the other end of the vapor chamber away from the plate condensing part is provided with fins 523; a closed cavity 521 is set inside the vapor chamber, and a capillary structure 552 is set inside the cavity 521; the capillary structure 552 is set around the inner wall of the cavity 521; the cold water inlet 53 and the cold water outlet 54 are respectively set on the opposite side of the plate-type condensing part department;

VC boards are equal temperature plates 52 and 56. The working diagram is shown in Figure 3. There is a sintered mesh structure attached to the inside of the cavity. The upper and lower layers are preferably 5-9 layers, and 7 layers are more preferable. The layer spacing is preferably 180-220 microns, and is further preferably 200 microns. Micron, which facilitates fluid adsorption to achieve phase change heat within the vapor chamber. When working, the liquid medium at the bottom of the vacuum chamber absorbs the heat from the water vapor at the bottom of the VC board to the fins, evaporates and diffuses into the vacuum chamber, conducts the heat to the condensation pipe, and then the condensed liquid passes through and adheres to the inner wall of the VC board. The reflow of sintered mesh with capillary force. In principle, VC boards are similar to heat pipes, but they are different in the way of conduction. Heat pipes are one-dimensional linear heat conduction, while the heat in VC boards is conducted on a two-dimensional surface, so the efficiency is higher. More energy efficient. The vapor chamber is equivalent to a two-dimensional heat pipe. Its existence can help the heat to spread quickly in the plane range and improve the heat exchange efficiency; the setting of the fin structure greatly increases the heat exchange area between the water vapor and the condenser. The amount increases, and the water production rate increases.

Preferably, the spoiler 552 is arranged in the middle of the cold water channel and is at the same distance from the isolation horizontal plates on both sides. And there are multiple welding points between the two side plates. By setting multiple welding points, on the one hand, the fixed connection between the two side plates can be increased, and on the other hand, it can be used to further disturb the flow and improve the heat exchange effect.

Preferably, through holes are provided on the spoiler 552 . Through the through holes, the flow resistance brought by the spoiler 552 can be further reduced, and at the same time, more fluid can flow through the interior of the spoiler 552 to further enhance heat transfer.

In the numerical simulation and experiment, it is found that the V-shaped angle of the spoiler 552 should not be too small, too small will lead to increased flow resistance, and at the same time it should not be too large, too large will lead to poor spoiler effect; The spacing should not be too large or too small, which will also lead to poor flow resistance or spoiler effect, and the gap between the spoiler 552 and the isolation horizontal plate should not be too small, too small will lead to increased flow resistance, and at the same time cannot Too big, too big will lead to poor spoiler effect. The present invention finds the best structural relationship with the best heat exchange effect under the condition that the flow resistance is 50KPa after a lot of numerical simulation and experimental research.

The spoiler is located in the middle between the two isolation horizontal plates, the V-shaped angle of the spoiler 552 is A, the height of the spoiler is H, and the distance between the isolation horizontal plates is S, then the following requirements are met:

Sin(A)=a*(S/H)-b*(S/H) ² -c;

Where a, b, c are parameters, 23.62<a<23.63, 8.68<b<8.69, 15.06<c<15.08;

If the calculated Sin(A)>1, then Sin(A)=1;

30°<a<150°, 1.10<S/H<1.61;

More preferably, 60°<a<110°, 1.2<S/H<1.4;

More preferably, a=23.627, b=8.6875, c=15.07;

The distance S between the isolation horizontal plates is the distance between the opposite walls of the adjacent horizontal plates.

The height of the spoiler H is the distance between the crest and trough of the spoiler.

More preferably, with the increase of S/H, a gradually decreases, and b and c gradually increase. By setting in this way, the optimized relational expression can be further approached to the actual numerical simulation and experimental results, and the heat exchange effect can be further improved.

As a preference, the value range of S is 20<S<100mm, and the value range of H is 18<H<90mm;

Preferably, the V-shaped included angle is a circular arc transition structure, as shown in FIG. 3 . Thereby further reducing resistance.

In the arc transition structure, the V-shaped included angle is A, which is the included angle formed between the extension lines of the two straight lines forming the included angle.

Preferably, there are two cold water inlets 53 and two cold water outlets 54, thereby forming two parallel cold water flow channels. Water enters the condenser from two inlets respectively, which increases the flow rate of cold water in the condenser and enhances heat exchange.

Preferably, the two cold water inlets 53 are respectively located at the edge positions on both sides of the plate-type condensing part, and the two cold water outlets 54 are located in the middle of the plate-type condensing part. The distance between the two cold water inlets 53 is greater than the distance between the two cold water outlets 54, so that the cold water flows from outside to inside in the condenser, and the flow area can cover the entire condenser.

Preferably, the plate-type condensing part 55 has a circular structure, and the design of the circular structure can improve its space utilization in the cylindrical tank and increase the contact area between the steam and the condenser as much as possible. The condensing device is composed of fins, vapor chambers, cold water channels, vapor chambers, and fins from top to bottom. Each layer plays its own role in the condensation process, and the layered design is convenient for processing.

Preferably, the plate-type condensing part is composed of an outer wall pipeline, 5 insulating horizontal plates and 6 spoilers, and the specific structure is shown in FIG. 4 . 5 isolation horizontal plates are evenly distributed in parallel, and 6 spoilers are interspersed between the isolation horizontal plates to achieve the purpose of circumventing the flow and realize the full contact between the cold seawater passing into the spoiler pipeline and the upper and lower VC plates , increasing the heat transfer efficiency.

Preferably, the lower wall surface of the upper vapor chamber 52 and the upper wall surface of the lower vapor chamber 56 are respectively the upper and lower end covers of the plate-type condensing part 55 .

The condenser 5 is arranged inclined to the horizontal plane, preferably, the inclination angle is 14-16 degrees, more preferably 15 degrees. If the inclination angle is too small, after the steam condenses on the upper surface of the condenser, it will easily cover the upper surface and not flow down with the inclination angle, which will affect the contact between the water vapor and the condenser and reduce the condensation efficiency; when the inclination angle is too large, it will take up more space in the vertical direction. Large, and the projected area in the horizontal direction is small, and the water vapor is not conducive to contact with it after rising, reducing the condensation efficiency.

The design of the fin structure, many strip plates of different lengths are vertically connected to the circular bottom plate, the side of the strip plate greatly increases the contact area between the condenser and the water vapor, improves the heat exchange speed, and condenses and liquefies the water The vapor adheres to the surface of the fins and then drips under the force of gravity.

Preferably, the fins 523 are the fins 51 and 57 .

Preferably, through holes are provided on the spoiler 552 . Through the provision of through holes, the flow resistance can be further alleviated, and fluid communication between the spoilers can be ensured to avoid partial short circuit of the spoilers.

The fresh water collection system includes an upper (outer) water receiving tray 62 and a lower (inner) water receiving tray 61, the upper water receiving tray 62 is located at the bottom of the condenser 5, and is located at the upper part of the lower water receiving tray 62, and the upper water receiving tray 62 The middle opening 621, the lower water tray 61 is located at the bottom of the hole 621, through the middle opening can ensure that the fresh water condensed by the condenser enters the lower water tray 61 through the hole. An upward vertical portion 622 is provided at the outermost end of the upper water tray 62 , connected to the vertical portion 622 is an inwardly extending horizontal portion 623 , and an upwardly inclined portion 624 extending inwardly along the horizontal portion 623 ; The horizontal part 623 is provided with a channel 625 for fresh water to flow into the lower water tray or directly connected to the pipeline to deliver the fresh water to the fresh water collection tank 13;

The lower water tray 61 is located at the bottom of the upper water tray opening 621, and the lower water tray 61 includes an upward vertical portion 612 located at the end of the lower water tray 61 including the outermost end. Connected to the straight portion 622 is an inwardly extending downwardly sloping sloping portion 613 and a centrally located channel 611 that connects to the fresh water collection tank.

In the present invention, by setting a new type of fresh water collection system, and by setting internal and external water trays, the height of the outer tray is slightly higher than that of the inner tray, so that the coverage area of fresh water collection can reach the entire interface of the vacuum tank, and at the same time, the gap between the inner tray and the outer tray can play the role of drainage. Through the above structure, the collection of fresh water can be realized in an all-round way, and the ability and effect of sea water and fresh water can be further improved.

The fresh water collection system is composed of an inner and outer ring water tray, a fresh water collection bucket and a fresh water pipeline. After the fresh water is produced, it flows into the fresh water collection bucket under the action of gravity. The inside of the tank is connected with the fresh water collection barrel through the fresh water pipeline to ensure that the internal pressure of the two is consistent, making the device work more stable. As shown in Figure 11, when working, the mist sprayed seawater encounters the finned turbulent flow evaporator to absorb heat and vaporize, the steam rises, and contacts with the integrated uniform temperature plate fin condenser that continuously cools seawater, and the steam is cooled Liquefied, condensed into liquid droplets, dripped to the inner and outer ring water trays under the action of gravity, and flowed to the fresh water collection bucket through the fresh water pipeline to realize the collection of fresh water.

Preferably, the seawater desalination system also includes a vacuum system, the vacuum system includes a vacuum tank 12, the condenser 5, the upper water tray 62, the lower water tray 61 and the condensation end 8 of the loop heat pipe 2 are arranged on in the vacuum system.

It should be noted that the dimensions marked in Fig. 17 of the fresh water collection system are only optimal dimensions.

Preferably, the vacuum system includes a vacuum maintaining device, the device adopts a sealed structure to maintain the internal pressure of the device, and uses the Venturi principle to evacuate the device to reduce the internal pressure of the device and reduce the boiling point of seawater when it evaporates. The Venturi tube is placed at the seawater outlet, and the consumption of seawater is relatively large. Part of it is treated and enters the tank for desalination, and the other part that accounts for the majority is directly discharged. During the discharge process, it passes through the Venturi tube. The sudden reduction of the cross-section leads to the increase of the flow velocity, and the pressure difference generated takes away the air in the tank to maintain the low pressure state in the tank, as shown in Figure 9. Port A is the liquid inlet, port C is the liquid outlet, and the cross-sectional area of B is reduced, which will increase the flow velocity at B, and the port D will communicate with B, and the pressure at D port will decrease, so that the air will be discharged from D port. Use the seawater discharged from the outlet to connect to A port, D port to connect with the tank body, and C port to drain water to achieve the purpose of vacuuming the vacuum tank. Port A is connected to the waste water outlet of the condensing end, port D is connected to the fresh water collection tank, and the waste seawater after passing through the Venturi tube is directly discharged from the waste water pipe connected to port C. D is connected with the fresh water collection tank, and the fresh water collection tank is connected with the whole gas of the vacuum tank 12, and the air in the device is taken out to maintain the vacuum environment.

Preferably, the desalinated waste water in the vacuum tank 12 is also discharged through the port A. Thereby further forming a vacuum.

As a preference, in order to utilize the evaporator heat absorbed in the unevaporated seawater, a circulating spraying system is designed, and the unevaporated seawater is sprayed in multiple cycles to make full use of the heat. As shown in Figure 10, the seawater desalination system also includes a seawater circulation spray system, the seawater circulation spray system is arranged in a vacuum system, and the seawater circulation spray system includes a circulation spray pump, a spray head 7 and In the circulation pipeline, the spray head 7 is arranged on the upper part of the condensation end 8; the circulation spray pump pumps the seawater in the vacuum system into the spray head 7, and then sprays to the condensation end.

Preferably, the shower head 7 is connected to a water return pipe. When working, the valve of the seawater inlet and outlet is firstly used to spray and replenish water in the tank 12. When the height of the seawater in the tank 12 reaches a certain level, the circulating spray pump is turned on for circulating spraying. When the evaporated waste brine reaches a certain concentration , the circulating spray pump stops working, the waste water outlet at the lower part of the tank is opened, and the concentrated brine is discharged through the waste water outlet. After the waste brine is exhausted, the valve at the waste water outlet is closed, and water replenishment and circular spraying are carried out again.

By setting the spray structure, the heat of the evaporator absorbed in the unevaporated seawater can be utilized to realize the conversion of seawater into fresh water to the greatest extent and realize the maximum utilization effect.

The shower head 7 is an atomizing shower head.

Preferably, a seawater concentration detection device is provided in the tank for detecting the concentration of seawater, and the controller automatically controls the discharge of seawater according to the detected concentration of seawater. If the measured seawater concentration exceeds a certain value, the controller controls the circulating spray pump to stop working, the wastewater outlet at the lower part of the tank is opened, and the concentrated brine is discharged through the wastewater outlet.

Preferably, a water level detection device is arranged in the tank to detect the water level in the vacuum tank. When the water level is lower than a certain value, the controller controls the circulation spray pump to stop working, and the valve of the water replenishment pipe is opened to replenish water. When the water level reaches a certain height, the water supply pipe valve is closed, and the circulating spray pump starts to work.

Preferably, when the water level exceeds a certain value, for example, the water level is too high, such as close to the height of the shower head, the circulating spray pump stops working, the waste water outlet at the bottom of the tank is opened, and the seawater is discharged through the waste water outlet. When the water level reaches a certain height, the valve at the outlet of the waste water is closed, and the spray is circulated again.

Preferably, the shower head 7 is an annular circular tube structure, and a plurality of shower heads are distributed on the circular tube.

Through the above-mentioned spraying structure and its setting, intelligent operation can be realized, and the efficiency of desalination of seawater can be improved at the same time.

As preferably, as shown in Figure 6, described loop heat pipe is plate type CPL capillary pump, preferably selects the transverse tube falling film evaporator (Fig. The hot plate acts as an evaporator in the plate CPL capillary pump, and the two are connected by a capillary tube. The liquid working medium absorbs heat and evaporates in the plate CPL heat collecting evaporator, and the liquid working medium is driven to flow by capillary force without external Provide additional driving force for it; the liquid working medium flows in, absorbs heat, evaporates into steam, and then discharges the steam, and so on to complete the cycle. .

Preferably, as shown in Fig. 7, the evaporation end is a plate structure, which is composed of an upper cover plate with a steam channel, a base of a liquid return chamber, a capillary core layer, a liquid header and a steam header. The upper cover is composed of a metal outer wall 211 and a steam channel 212, the liquid return chamber base is composed of a base outer wall 215 and a liquid channel 214, and the capillary core layer 213 is located between the upper cover and the liquid return chamber base. The capillary core layer is placed on the upper part of the base of the liquid return chamber, and is pressed tightly by the upper cover plate, thereby separating the liquid return channel and the steam channel; between the upper cover plate with the steam channel and the liquid return chamber, four Fluorine gasket 216 and D05 sealant are used for sealing and connecting with bolts, so that the flat plate heat collecting evaporator can be disassembled.

At least a portion of the liquid in the liquid channel enters the vapor channel through the wick. When working, the evaporator absorbs heat, the liquid in the steam channel evaporates, and the liquid medium inside the liquid channel 214 also evaporates, and the evaporated gas diffuses to the steam channel 212 through the small holes on the capillary wick 213 and gathers in the steam collection box 217 Inside, through the evaporation circuit to the condensation end, the steam dissipates heat and liquefies at the condensation end, and the liquefied medium flows back into the liquid channel 214 through the capillary force of the capillary wick to complete a cycle and realize heat transfer. Compared with traditional single-phase heat exchange, two-phase heat exchange can improve heat transfer efficiency and reduce heat loss during heat exchange.

The solar thermal collector includes a solar thermal collector plate, and the upper surface of the evaporation end is attached to the lower surface of the solar thermal collector plate 1 .

Preferably, the upper surface of the evaporation end is the solar thermal collector plate 1 .

As a preference, the evaporation system is composed of a plate-type CPL capillary pump, a solar collector plate, an electric heating plate, and a fin-type turbulent flow evaporator, and the specific structure is shown in FIG. 5 .

As a preference, the solar heat collecting plate and the electric heating plate form a heat collecting system, and the solar heat collecting plate and the electric heating plate are distributed on both sides of the plate type CPL capillary pump, wherein the electric heating plate is arranged on the backlight side, and the heat source is mainly solar heat collecting, necessary When the electric heating plate provides electric auxiliary heating, the heat conduction medium in the CPL capillary pump is phase-transformed to heat to the fin-type turbulent flow evaporator placed inside the tank to evaporate seawater.

As a preference, only solar heat collecting panels or only electric heating panels can be utilized. When only using the electric heating plate, the electric heating plate is arranged on the upper part and/or the lower part of the evaporation end of the loop heat pipe.

As a preference, as shown in Figure 8, the condensing end 8 (i.e. the seawater evaporator) is a tube-sheet heat exchange structure, including an inlet header 82, an outlet header 86, an inlet heat exchange tube 83, an outlet heat exchange tube 85 and A plate group 84, the inlet header 82 is connected to the inlet heat exchange tube 83, and the inlet heat exchange tube 83 is connected to the corresponding plate group 84, the plate group 84 is a heat exchange channel formed by combining two plates, The plate group 84 is connected to the outlet heat exchange tube 85, the outlet heat exchange tube 85 is connected to the outlet header 86, the steam from the evaporation end enters the inlet heat exchange tube 83 through the inlet header 82, and then enters the plate group 84 through the inlet heat exchange tube 83 , and then pass through the plate group 84 for heat exchange, then enter the outlet heat exchange tube 85, and then discharge through the outlet header 86. The inlet heat exchange tube 83 , the outlet heat exchange tube 85 and the plate group 84 are the main components of heat exchange. Preferably, the inlet header 82 and outlet header 86 also participate in heat exchange. The condensing end 8 is soaked in seawater or the seawater is sprayed to the condensing end by a spraying device for heat exchange.

The invention provides a new tube-sheet heat exchange structure, through which the tube-sheet combination can further reduce the resistance, expand the heat dissipation area and improve the heat dissipation efficiency. Especially as a heat exchanger for seawater desalination spraying, it can improve the effect of seawater desalination.

Preferably, there are multiple inlet heat exchange tubes 83 , and each inlet heat exchange tube 83 corresponds to a plate group 84 . The plurality of plate packs are parallel spaced apart structures. Preferably, there are multiple outlet heat exchange tubes 85 , and each outlet heat exchange tube 85 corresponds to a plate group 84 .

Preferably, the plate packs are distributed vertically. This enables the spray water to fully exchange heat with the plate pack.

Preferably, inlet header 82 and outlet header 86 are located on the same side of the plate pack.

The inlet heat exchange tube, outlet heat exchange tube and plate group are the main parts of heat exchange, and preferably, the inlet header and outlet header also participate in heat exchange. The condensing end is soaked in seawater or the seawater is sprayed to the condensing end by a spraying device for heat exchange.

In the numerical simulation and experiment, it is found that the distance between the plate groups should not be too small, too small will increase the flow resistance of the spray water, and it will not be well distributed to the entire heat exchange plate, and the heat exchange effect will not be good. , and at the same time, it should not be too large. If it is too large, the spray water will flow down without heat exchange, causing a heat exchange short circuit, resulting in poor heat exchange effect. Similarly, the circulation channel area of the heat exchange plate group cannot be too large, nor can it be too large. Small, too small will result in insufficient heat transfer, and too large will result in excessive heat transfer; the height of the heat exchange plate group should not be too large or too small, too large or too small will lead to poor heat transfer effect. The flow area of the inlet heat exchange tube and the outlet heat exchange tube is also corresponding to the internal flow area of the heat exchange plate group, and cannot be too large or too small, which will lead to poor heat exchange effect. The present invention finds the best structural relationship for the best heat exchange effect through a large number of numerical simulations and experimental researches, so as to ensure full utilization of heat.

The distance between adjacent plate groups is S1, the length of the plate group is H1, the flow area of the plate group is V1, the flow area of the inlet heat exchange tube and the outlet heat exchange tube are the same, the flow area of the inlet heat exchange tube is V2, then meet the following requirements:

(S1/H1)*10=a+b*LN(V2/V1*10); LN is a logarithmic function,

Where a, b are parameters, 2.67<a<2.68; 1.99<b<2;

More preferably, a=2.674, b=1.996;

Among them, 0.099<V2/V1<0.13; 0.04<S1/H1<0.05;

The spacing between adjacent plate groups is S1 is the distance between the opposite wall surfaces of adjacent plate groups.

The length H1 of the plate group is the length parallel to the flow direction of the fluid in the plate group, see FIG. 8 .

More preferably, as V2/V1 increases, a gradually increases and b gradually increases. By setting in this way, the optimized relational expression can be further approached to the actual numerical simulation and experimental results, and the heat exchange effect can be further improved.

As a preference, in the evaporation system (i.e., at the condensing end of the heat pipe), the evaporator 8 adopts 15 single-piece heat sinks placed in parallel at equal intervals, connected in parallel by headers, and finally fixed into groups by heat sink racks. The structure is shown in Figure 8 .

Preferably, a power device is provided on the pipeline from the condensing end of the heat pipe to the evaporating end of the heat pipe (solar collector), which is used to drive the heat-exchanged fluid at the condensing end to transfer to the evaporating end for heat absorption.

Further preferably, the power unit is a drive pump.

The evaporator 8 is processed by laser welding and bulging technology. The fluid flow path in the evaporator has a U-shaped structure, and small particles are distributed on the U-shaped path to achieve the purpose of disturbing the flow, so that the inner wall of the evaporator and the fluid heat transfer medium are fully integrated. Contact to improve heat transfer efficiency.

The inlet header 82 and the outlet header 86 are respectively connected to the steam inlet pipe 81 and the condensed water outlet pipe 87 . Preferably, a flow stabilizing device is provided in the steam (fluid) inlet pipe 81 of the inlet header, and the structure of the flow stabilizing device 14 is shown in FIGS. 12 and 13 . The flow stabilization device 14 is a sheet structure, and the sheet structure is arranged on the cross section of the steam inlet pipe 81; the flow stabilization device 14 is composed of a square and a regular octagonal structure, thereby forming a square through hole 141 and a regular octagonal structure. The edge-shaped through hole 142. As shown in Figure 1, the side length of the square through hole 141 is equal to the side length of the regular octagonal through hole 142, and the four sides 143 of the square through hole are respectively the sides 43 of four different regular octagonal through holes. The four sides 143 spaced apart from each other are the sides 143 of four different square through holes.

Two-phase flow and instability widely exist in heat exchange devices, such as loop heat pipes, because there is a vapor phase that drives the liquid phase to flow. However, when two-phase fluid enters the heat exchange equipment, it will cause water hammer phenomenon caused by the expansion of the space. Also because of the large amount of fluid, it will also deteriorate the heat exchange. When the vapor and liquid phases of the two-phase working medium are not uniformly mixed and flow discontinuously, the large-sized liquid mass will occupy the space of the vapor mass at high speed, resulting in unstable two-phase flow, which will violently impact the equipment and pipelines, resulting in strong vibration and shock. Noise seriously threatens the operation safety of heat pipe equipment.

The present invention adopts a novel structure of the flow stabilizing device, which transfers the field of the flow stabilizing device in the loop heat pipe, and applies it to the inlet pipe of the evaporation end of the loop heat pipe. Because the steam inlet pipe 81 is connected to the inlet header 82 , when the steam-water mixture enters the inlet header 82 , a water hammer phenomenon caused by space expansion will occur. The present invention adopts a novel structural flow stabilizing device, which has the following advantages:

1) The present invention provides a new type of flow stabilizing device with a combination of a new square through hole and a regular octagonal through hole, through the square and the regular octagon, the clamp formed by the sides of the formed square hole and the regular octagonal hole The angles are all greater than or equal to 90 degrees, so that the fluid can fully flow through every position of each hole, avoiding or reducing short circuit of fluid flow. The invention separates the two-phase fluid into a liquid phase and a gas phase through a new structure of the flow stabilization device, divides the liquid phase into small liquid masses, and divides the gas phase into small bubbles, inhibits the backflow of the liquid phase, promotes the smooth flow of the gas phase, and stabilizes The effect of flow has the effect of reducing vibration and noise. Compared with the current stabilizing device in the prior art, the current stabilizing effect is further improved, and the manufacture is simple.

2) The present invention makes the square and regular octagonal through-holes evenly distributed through a reasonable layout, so that the fluid on the overall cross-street surface is evenly divided, avoiding the uneven division of the ring structure along the circumferential direction in the prior art. Even problem.

3) The present invention evenly distributes the spacing between square holes and regular octagonal through holes, so that the large holes and small holes are evenly distributed on the overall cross section, and the position of the large holes and small holes of the adjacent flow stabilization device changes , making the separation effect better.

4) In the present invention, by setting the flow stabilizing device as a sheet structure, the structure of the stabilizing device is simple and the cost is reduced.

The present invention divides the gas-liquid two-phase at all cross-sectional positions of all heat exchange tubes, thereby realizing the separation of the gas-liquid interface and the gas-phase boundary layer and the contact area of the cooling wall surface on the entire heat exchange tube section, and enhancing the disturbance. The noise and vibration are greatly reduced, and the fluid entering the inlet header 82 can fully exchange heat with sea water, thereby enhancing heat transfer.

Preferably, the flow stabilizing device includes two types, as shown in FIGS. 12 and 13 , the first type is a square central flow stabilizing device, and the square is located at the center of the steam inlet pipe or condensation pipe, as shown in FIG. 13 . The second type is a regular octagonal central flow stabilization device, and the regular octagonal shape is located at the center of the steam inlet pipe or condensation pipe, as shown in Figure 12 . As a preference, the above two types of flow stabilizing devices are arranged adjacently, that is, the types of the flow stabilizing devices arranged adjacently are different. That is, the regular octagonal central current stabilizing device is adjacent to the square central current stabilizing device, and the square central current stabilizing device is adjacent to the regular octagonal central current stabilizing device. The present invention evenly distributes the intervals between square holes and regular octagonal holes, so that the large holes and small holes are evenly distributed on the overall cross-section, and through the position changes of the large holes and small holes of the adjacent flow stabilization device, it is possible to pass The fluid in the large hole passes through the small hole next, and the fluid passing through the small hole passes through the large hole next, further separating and promoting the mixing of gas and liquid, so that the separation effect of shock absorption and noise reduction is better.

Preferably, the cross section of the steam inlet pipe 81 is square.

Preferably, along the direction of fluid flow, the diameter of the steam inlet pipe 81 increases continuously. The main reasons are as follows: 1) By increasing the pipe diameter of the steam inlet pipe, the flow resistance can be reduced, so that the evaporated gas in the steam inlet pipe continuously moves toward the direction of pipe diameter increase, thereby further promoting the circulation flow of the loop heat pipe. 2) By increasing the diameter of the steam inlet pipe, the impact phenomenon caused by the increase in the volume of the steam outlet can be reduced.

Preferably, along the direction of fluid flow, the diameter of the steam inlet pipe 81 increases continuously. The change in the amplitude of the above-mentioned tube diameter is the result obtained by the applicant through a large number of experiments and numerical simulations. Through the above-mentioned setting, the circulation flow of the loop heat pipe can be further promoted, the overall uniform pressure can be achieved, and the impact phenomenon can be reduced.

Preferably, a plurality of flow stabilizing devices are arranged in the steam inlet pipe 81 , and the closer to the inlet header 82 , the smaller the spacing between the flow stabilizing devices. Assuming that the distance from the inlet header 82 is H, the distance between adjacent flow stabilization devices is S, S=F ₁ (H), that is, S is a function of the height H as a variable, and S' is the first derivative of S, Meet the following requirements:

S'>0;

The main reason is that the closer to the inlet header 82, the vibration and noise will increase continuously, and it is more and more necessary to further alleviate the vibration and noise. Therefore, the distance between adjacent flow stabilization devices that need to be provided becomes shorter and shorter.

From the outlet of the steam inlet pipe to the inlet header, because the space of this section suddenly becomes larger, the change of space will cause the gas to flow upward rapidly and accumulate, so the change of space will cause the accumulated vapor phase (vapor mass) to flow from the steam inlet When the tube position enters the condensation header, due to the difference in gas (steam) and liquid density, the air mass will move upward quickly when it leaves the connecting tube position, and the liquid in the original space of the air mass that is pushed away from the wall by the air mass will also rebound quickly and hit the wall, forming a collision phenomenon . The more discontinuous the gas (steam) liquid phase, the greater the accumulation of air masses and the greater the energy of water hammer. The impact phenomenon will cause large noise vibration and mechanical shock, causing damage to the equipment. Therefore, in order to avoid this phenomenon, the distance between adjacent flow stabilization devices is getting shorter and shorter, so as to continuously separate the gas phase and liquid phase during fluid delivery, thereby reducing vibration and noise to the greatest extent.

Through experiments, it is found that through the above-mentioned setting, the vibration and noise can be reduced to the greatest extent, and the heat exchange effect can be improved at the same time.

Further preferably, the closer the distance to the inlet header 82 is, the shorter the distance between adjacent flow stabilizing devices is, and the range increases continuously. That is, S" is the second derivative of S, which meets the following requirements:

S"<0;

Through experiments, it is found that the vibration and noise can be further reduced by about 7% through such setting.

Preferably, multiple flow stabilizing devices are arranged in the steam inlet pipe, and the closer the steam inlet pipe is to the inlet header 82, the smaller the side length of the square becomes. The distance from the inlet header 82 is H, the side length of the square is C, C=F ₂ (H), and C' is the first derivative of C, which meets the following requirements:

C'>0;

Further preferably, the closer the distance to the inlet header 82 is, the smaller the side length of the square is and the range is continuously increased. C" is the second derivative of C, which meets the following requirements:

C"<0.

For specific reasons, refer to the change in the spacing of the flow stabilization device above.

Preferably, the distance between adjacent flow stabilizing devices remains unchanged.

Preferably, a slit is arranged on the inner wall of the steam inlet pipe, and the outer end of the flow stabilizing device is arranged in the slit.

Preferably, the steam inlet pipe is welded in a multi-stage structure, and a flow stabilization device is provided at the joint of the multi-stage structure.

Through analysis and experiments, we know that the distance between the flow stabilization devices should not be too large. If it is too large, the effect of shock and noise reduction will not be good. At the same time, it should not be too small. If it is too small, the resistance will be too large. Similarly, the square The side length cannot be too large or too small, which will also lead to poor shock and noise reduction effects or excessive resistance. Therefore, the present invention, through a large number of experiments, first satisfies the normal flow resistance (total pressure is below 2.5Mpa, Or when the resistance along the path of a single steam inlet pipe is less than or equal to 5Pa/M), the vibration and noise reduction can be optimized, and the best relationship of each parameter has been sorted out.

Preferably, the distance between adjacent flow stabilization devices is S1, the side length of the square through hole is L1, the steam inlet pipe has a square cross-section, and the side length of the square cross-section of the steam inlet pipe is L2, meeting the following requirements:

S1/L2＝a*(L1/L2) ² +b*(L1/L2)-c

Where a, b, c are parameters, among which 39.8<a<40.1, 9.19<b<9.21, 0.43<c<0.44;

9<L2<58mm;

1.9<L1<3.4mm;

15<S1<31mm.

More preferably, a=39.87, b=9.20.c=0.432

Further preferably, as L1/L2 increases, a and b become larger and c becomes smaller.

Preferably, the side length L1 of the square through hole is the average of the inner and outer side lengths of the square through hole, and the side length L2 of the square section of the steam inlet pipe is the average of the inner and outer side lengths of the steam inlet pipe.

Preferably, the length of the outer side of the square through hole is equal to the length of the inner side of the square section of the steam inlet pipe.

Preferably, as L2 increases, L1 also increases continuously. But with the increase of L2, the increasing range of L1 becomes smaller and smaller. This change in law is obtained through a large number of numerical simulations and experiments. Through the change in the above law, the heat exchange effect can be further improved and the noise can be reduced.

Preferably, as L2 increases, S1 decreases continuously. But with the increase of L2, the range of S1's constant decrease becomes smaller and smaller. This change in law is obtained through a large number of numerical simulations and experiments. Through the change in the above law, the heat exchange effect can be further improved and the noise can be reduced.

For other parameters, such as pipe wall, shell wall thickness and other parameters can be set according to normal standards.

Preferably, the fluid in the heat pipe is water.

Preferably, the diameter of the steam inlet pipe is larger than that of the return pipe. The main purpose is to increase the resistance of the return pipe and reduce the resistance of the steam inlet pipe, making it easier for the steam to flow from the evaporation part, and the loop heat pipe can form a better circulation.

Although the present invention has been disclosed above with preferred embodiments, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention, so the protection scope of the present invention should be based on the scope defined in the claims.

Claims (5)

1. a kind of vacuum system, including vacuum keeping apparatus, device uses sealing structure, to maintain device internal pressure, utilizes Venturi principle vacuumizes, boiling point when device internal pressure being made to reduce to reduce evaporation of seawater；Venturi tube is placed on sea At water out, seawater a part enters after treatment for desalinating in tank body, and the another part to occupy the majority is expelled directly out, and is being arranged By Venturi tube during out, when using cold water flow, cross section reduces the pressure difference for causing flow velocity to increase and generating suddenly The air in tank is taken away, low-pressure state in tank body is maintained.

2. vacuum system as described in claim 1, which is characterized in that A mouthfuls of Venturi tube one end is liquid-inlet, other end C Mouth is liquid outlet, is connected at B with A mouthfuls, reduced cross-sectional area, and flow velocity at B can be made to increase, and D mouthfuls are arranged at B company at lower end, with B Logical, D mouthfuls of pressure reduce, so that air be drained from D mouthfuls；A mouthfuls are connect using from the seawater of discharge, D mouthfuls are connected with tank body, C mouthfuls of rows Water, to achieve the purpose that vacuum tank to vacuumize.

3. vacuum system as claimed in claim 2, which is characterized in that D is connected with fresh water collecting tank, and fresh water collecting tank and true Slack tank overall gas communicates, and air in device is taken out of, maintains vacuum environment.

4. a kind of seawater desalination system, the system comprises vapo(u)rization system, condenser system and fresh water collecting system, seawater is evaporating System is evaporated generation steam, and then steam, which condense in condenser system, becomes fresh water, and then fresh water passes through fresh water collecting System is collected, which is characterized in that

The vapo(u)rization system includes solar thermal collector and loop circuit heat pipe, and the loop circuit heat pipe evaporation ends absorb solar energy, then It exchanges heat in condensation end and seawater, makes evaporation of seawater；

The condenser system includes condenser, the vapor that the condenser condensation evaporation of seawater generates；

The fresh water collecting system includes drip tray, and the drip tray is located at the lower part of condenser, for collecting condenser condensation The condensed water of generation；

The condensation end of condenser, drip tray and loop circuit heat pipe is sequentially arranged from top to bottom.

5. seawater desalination system as claimed in claim 4, which is characterized in that the seawater desalination system further includes vacuum system System, the condenser, upper water tray, lower accepting water disk and loop circuit heat pipe condensation end be arranged in vacuum system, the vacuum system System is vacuum system described in one of claim 1-3.