Solar low-temperature evaporation seawater desalination device

Abstract

A seawater desalination device, relating to the technical field of seawater desalination. The device comprises a seawater evaporator, provided with a housing having a double-layer inner vacuum structure. A tubular evaporation core is disposed within the housing, and is composed of a microporous tube and a capillary material layer in a radial direction from inside to outside. The circumferential wall of the microporous tube is uniformly provided with micropores passing through the wall of the tube. One end of the microporous tube serves as an inlet structural member, and the end of the inlet structural member facing away from the evaporation core is provided with a raw-water pipe connection end, used for introducing seawater into the capillary material layer. An outlet structural member is provided with a pipe opening communicating with the microporous tube, and is further provided with a water outlet channel communicating the inside and outside of a condensation chamber. The device has the advantages of delivering heat to the capillary material layer via the microporous tube to evaporate seawater, and enabling backwashing via the microporous tube.

Description

Solar low-temperature evaporation seawater desalination device Technical Field

[0001] The present invention relates to the technical field of seawater desalination, in particular to a seawater desalination device with an improved evaporator, so that the device can be applied to a wider range of environments. Background Art

[0002] Desalinating seawater into drinkable fresh water is an effective solution to alleviate the problem of fresh water resource shortage. Currently, commonly used methods include thermal separation, membrane separation, chemical separation, etc. Membrane separation includes reverse osmosis and electrodialysis. Membrane separation requires a pressurized device. Thermal separation is a method in which seawater absorbs heat and evaporates to separate water and salt, thereby obtaining fresh water. It includes multi-stage flash evaporation and multi-effect distillation. Reverse osmosis, electrodialysis, multi-stage flash evaporation or multi-effect evaporation consume a large amount of fossil fuels, have high operating costs, and are uneconomical methods of seawater desalination.

[0003] Solar-driven evaporation of seawater from the surface is a relatively economical method for producing fresh water. It uses solar energy to convert into thermal energy, heats the water, and causes the seawater to undergo a liquid-to-gas phase transition on the surface, achieving evaporation and collection of fresh water. Existing technologies mostly focus on improving the performance of photothermal conversion materials, enhancing water transmission, and reducing salt crystallization. However, there are no mature products in engineering applications and product structures.

[0004] On the one hand, there is a demand for seawater desalination in islands, coastal areas, fishing boats, and large cargo ships. On the other hand, it is noted that there are many low-cost heat sources in these environments. Therefore, it is necessary to provide a desalination device with a simple structure and high efficiency that can use solar energy and a variety of low-cost heat sources as seawater evaporation energy to desalinate high-salt water sources. Summary of the Invention

[0005] The main purpose of the present invention is to provide a seawater desalination device with simple structure and high efficiency;

[0006] Another object of the present invention is to provide a seawater desalination device that can utilize solar energy as a heat source.

[0007] To achieve the above-mentioned main purpose, the seawater desalination device provided by the present invention includes a seawater evaporator, which has a shell with a double-layer internal vacuum structure, one end of the shell is provided with an inlet structural member, and the other end is provided with an outlet structural member; an evaporation core, the evaporation core is a tubular body, one end of the tubular body is fixed on the inlet structural member, and the other end is fixed on the outlet structural member, the space between the evaporation core and the shell forms a condensation chamber, and the tubular body is respectively composed of a microporous tube and a capillary material layer from the inside to the outside in the radial direction; the peripheral wall of the microporous tube is evenly distributed with micropores penetrating the tube wall, the microporous tube is located at one end of the inlet structural member and sealed, and the end of the inlet structural member facing away from the evaporation core is provided with a raw water pipe connection end for introducing seawater into the capillary material layer; the outlet structural member is provided with a pipe mouth connected to the microporous tube, and is also provided with an outlet channel connected to the inside and outside of the condensation chamber.

[0008] As can be seen from the above scheme, the shell of the double-layer internal vacuum structure has good thermal insulation capabilities. The structure of the outer capillary material layer is extremely simple. After the seawater enters the inlet structure through the pipe hole on the raw water connection end, the capillary material layer can quickly absorb the seawater. The microporous tube has multiple functions. It can introduce low-cost heat sources from the outlet end, such as hot exhaust gas and other household or industrial waste heat, and transfer the heat to the capillary material through the holes evenly distributed throughout the tube wall, evaporating the seawater, and then condensing it into fresh water in the condensation chamber. It is then discharged to the fresh water tank through the outlet channel connecting the inside and outside of the condensation chamber. A significant function of the microporous tube is that when too much salt accumulates in the capillary material layer, it can be connected to pressurized seawater through the pipe mouth for backwashing, flushing the salt in the capillary material layer into the condensation chamber and discharging it through the outlet channel.

[0009] To achieve another object of the present invention, a further solution is that the shell is made of a light-transmitting material; and a photothermal material layer is radially disposed outside the capillary material layer. The advantage of this solution is that the seawater desalination device can utilize solar energy to convert into thermal energy for evaporation. Sunlight passes through the shell made of light-transmitting material and enters the photothermal material layer. The photothermal material layer converts the light energy into thermal energy to evaporate the seawater in the capillary material layer. In this solution, the microporous tubes are primarily used for backwashing. Of course, if a low-cost heat source is available, it is entirely possible to operate in parallel with solar energy under desalination conditions, or the two can be used alternately.

[0010] A further solution is to further include a concentrating reflector, which is located on the side of the seawater evaporator facing away from sunlight. This solution has the advantage that, in addition to directing sunlight onto the front of the seawater evaporator, the concentrating reflector can also reflect nearby sunlight onto the side of the seawater evaporator that is not directly exposed to sunlight, thereby improving the efficiency of solar energy.

[0011] Another further solution is that the microporous tube is made of an electrically heated material. The advantage of this solution is that the electric heating structure is relatively simple, and the microporous tube made of an electrically heated semiconductor material has the advantages of high temperature resistance, oxidation resistance, and low aging.

[0012] A further solution is to provide an insulating electric heating layer between the microporous tube and the capillary material layer in the radial direction. This solution has the advantage of being low-cost compared to the previous solution. The electric heating layer, which is made of relatively cheap materials, can heat the capillary material layer after being energized.

[0013] A further solution is to have multiple layers of the capillary material layer, with an air-permeable and water-impermeable material layer and a heat-conducting layer disposed between each layer, and the multiple heat-conducting layers being connected in series. This solution has the advantage of relatively expanding the evaporation area of ​​the capillary material and making the heating of each capillary material layer more uniform.

[0014] In a further embodiment, at least the raw water connection end of the inlet structure is made of a water storage material, which is in close contact with the capillary material layer. The raw water connection end is a concave tube hole, into which the outlet end of the raw water pipe is inserted, and the peripheral wall of the inserted section of the raw water pipe is provided with evenly distributed outlet holes. This embodiment has the advantage of improving the strength of the inlet structure while ensuring that the raw water connection end can effectively transfer seawater to the capillary material layer.

[0015] A further solution is to connect the nozzle to a tube that selectively connects to a backwash water pipe, a hot gas pipe, or a hot exhaust pipe, wherein the water channel includes a condensate outlet and a backwash outlet. This solution has the advantage of effectively utilizing the multiple functions of the microporous tube, and allowing for separate condensate and backwash outlets, making it more convenient to use.

[0016] A further solution is to have multiple seawater evaporators connected in parallel, with the raw water connection end connected to the raw water pipe and then connected in parallel to the raw water main pipe, and the outlet end connected to the fresh water outlet pipe and then connected in parallel to the fresh water outlet main pipe. This solution has the advantage of allowing for quick assembly based on actual fresh water demand, thereby meeting fresh water needs.

[0017] In a further embodiment, the inlet structure is further provided with an outlet duct connecting the interior and exterior of the condensing chamber; and further includes a preheating unit for preheating the raw water entering the seawater evaporator. The preheating unit includes an outlet pipe connected to the outlet duct, which transfers heat from the hot steam exhausted from the seawater evaporator to the raw water entering the inlet structure. This embodiment has the advantage of utilizing the heat energy in the exhaust gas discharged by the desalination device to balance the pressure. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] FIG1 is a schematic structural diagram of a first embodiment of the present invention;

[0019] FIG2 is a schematic structural diagram of a seawater evaporator in a seawater desalination device according to the present invention;

[0020] FIG3 is a cross-sectional view taken along line AA in FIG2 ;

[0021] FIG4 is a partial enlarged view of B in FIG2 , which is also a schematic structural diagram of the inlet structural member of the first embodiment;

[0022] FIG5 is a sectional view taken along line DD in FIG4 ;

[0023] FIG6 is a partial enlarged view of C in FIG2 , which is also a schematic structural diagram of the outlet structure of the first embodiment;

[0024] FIG7 is a left side view of FIG6;

[0025] FIG8 is a schematic structural diagram of a second embodiment of the present invention;

[0026] FIG9 is a schematic diagram of an embodiment in which the capillary material layer has a three-layer structure;

[0027] FIG10 is a schematic structural diagram of a microporous tube that is a square tube and is wrapped with three layers of capillary material;

[0028] FIG11 is a schematic diagram showing the connection of multiple seawater evaporators in the eighth embodiment, which is composed of five evaporators connected in parallel.

[0029] Wherein: raw water unit 1; water inlet valve 11; filter 12; lift pump 13; seawater storage tank 14; backwash pump 15; backwash water valve 16; seawater outlet valve 17; preheating unit 2; raw water pipe 21; raw water main pipe 21A; outlet pipe 22; auxiliary condensing chamber 23; pressure relief valve 24; fresh water return pipe 25; seawater evaporator 3; shell 35; condensing chamber 351; inlet structural member 36; raw water pipe connecting end 361; outlet duct 362; outlet structural member 37; evaporation core 38; microporous tube 381; insulation Thermal layer 382; capillary material layer 383; thermal conductive layer 3831; air-permeable and water-impermeable material layer 3832; photothermal material layer 384; focusing reflector 39; supporting auxiliary unit 4; pipe mouth 40; outlet 401; outlet 402; backwash drain pipe 41; backwash drain main pipe 41A; backwash water pipe 42; hot air pipe 43; hot exhaust pipe 44; purifier 45; insulated electric heating layer connection 46; fresh water outlet pipe 47; fresh water outlet main pipe 47A; fresh water storage tank 48; seawater desalination device 1000.

[0030] The present invention is described in detail below with reference to the embodiments of the present invention and the accompanying drawings. DETAILED DESCRIPTION First embodiment

[0031] 1 , a seawater desalination device 1000 of this embodiment is composed of a raw water unit 1 , a preheating unit 2 , a seawater evaporator 3 and a supporting auxiliary unit 4 .

[0032] Raw water unit 1

[0033] Lift pump 13 pumps seawater into seawater storage tank 14. The inlet pipe is equipped with an inlet valve 11 and a filter 12, which is used to filter impurities in the seawater. Seawater storage tank 14 is typically located high in the entire system, with the liquid level sufficient to ensure that it can flow through preheating unit 2 and into the inlet structure 36 of seawater evaporator 3. That is, when seawater outlet valve 17 is open, seawater is supplied to evaporator 3 by its potential energy. Furthermore, a backwash pump 15 is also installed in seawater storage tank 14, which supplies backwash seawater to backwash pipe 42 via backwash water valve 16.

[0034] Preheating unit 2

[0035] The preheating unit 2 in this example primarily consists of an outlet pipe 22, a raw water pipe 21, and a secondary condensing chamber 23. The raw water pipe 21 has a spiral section located within the secondary condensing chamber 23. The outlet pipe 22 leads into the secondary condensing chamber 23. One end of the raw water pipe 21 is connected to a raw water pipe connection 361 (see Figure 4) on the inlet structural member 36, and the other end is connected to the seawater storage tank 14 via a seawater outlet valve 17. One end of the outlet pipe 22 is connected to an outlet duct 362 (see Figure 4) on the inlet structural member 36, and the other end is connected to the secondary condensing chamber 23. A vent pipe is provided at the top of the secondary condensing chamber 23, which vents to the atmosphere via a pressure relief valve 24. A fresh water return pipe 25 is provided at the bottom to return fresh water condensed in the secondary condensing chamber 23 to the fresh water storage tank 48. In this way, the heat from the hot steam discharged from the seawater evaporator 3 through the outlet pipe 22 is transferred to the raw water before entering the inlet structural member 36, thereby preheating the raw water and improving the utilization rate of thermal energy.

[0036] Seawater evaporator 3

[0037] Referring to Figure 2, the seawater evaporator 3 has a shell 35 with a double-layer vacuum structure. The double-layer vacuum structure can effectively prevent the heat inside the shell 35 from being conducted outward. In this example, the shell 35 is made of a light-transmitting material such as acrylic or glass. An inlet structural member 36 is provided at one end of the shell 35, and an outlet structural member 37 is provided at the other end. The direction of sunlight exposure is indicated by a row of arrows in Figure 1. A focusing reflector 39 is provided on the side of the shell 35 facing away from the sunlight. The evaporation core 38 is a tubular body, one end of which is fixed to the inlet structural member 36, and the other end is fixed to the outlet structural member 37. The space between the evaporation core 38 and the shell 35 forms a condensation chamber 351.

[0038] 3 , the evaporation core 38 is a multi-layer tubular body, one end of which is fixed to the inlet structural member 36 and the other end is fixed to the outlet structural member 37 . Seen from the radial direction, from the inside to the outside, there are the microporous tube 381 , the insulating electric heating layer 382 , the capillary material layer 383 and the photothermal material layer 384 . From an axial perspective, microporous tube 381 is located at one end of inlet structural member 36 and sealed. Microporous tube 381 is primarily used for backwashing and, secondarily, for hot air transmission and electrical heating. Its circumferential wall is uniformly distributed with holes penetrating the tube wall. The pore size can range from nanometers to micrometers, or even millimeter levels. The nanometer-level pore size ranges from 10 nanometers to 100 nanometers, the micrometer-level pore size ranges from 1 micron to 50 microns, and the millimeter-level pore size ranges from 1 millimeter to 20 millimeters. The pore spacing can be determined experimentally, with the millimeter-level pore spacing ranging from 10 millimeters to 50 millimeters. In summary, the pore size and pore spacing are preferably set to allow hot air to quickly pass through capillary material layer 383, preferably generating high-speed water flow during backwashing. In this example, microporous tube 381 is made of a corrosion-resistant material such as ceramic or stainless steel. The insulating electric heating layer 382 is formed by wrapping an insulating heating wire around a microporous tube 381. The capillary material layer 383 can be made of cotton, linen, fabric, wool, polyester, nylon, or other materials with high water absorption, as long as they absorb water and form capillary channels within the capillary material to facilitate water migration. The photothermal material layer 384 is made of a nano-metal-based or nano-carbon-based photothermal conversion material with high thermal conversion efficiency. It has both heat absorption and photothermal conversion functions, and materials with high heat absorption and photothermal conversion efficiency are preferably selected. The space between the evaporation core 38 and the housing 35 forms the condensation chamber 351.

[0039] Auxiliary Unit 4

[0040] 1 , the auxiliary unit 4 includes a backwash drain pipe 41 , a backwash water pipe 42 , a hot gas pipe 43 , a hot tail gas pipe 44 , a purifier 45 , an insulated electric heating layer connection 46 , a fresh water outlet pipe 47 and a fresh water storage tank 48 .

[0041] 4 and 5 , the circumferential wall of the inlet structural member 36 is fixedly connected to the shell 35. In this example, the inlet structural member 36 is made of a water storage material. The water storage material can be an organic material or an inorganic material. Organic materials include polymer absorbent resins, hydrophilic gels, silica gels, etc., and inorganic materials include water-storage clay, etc. A raw water pipe connection end 361 is provided on the side of the inlet structural member 36 facing away from the evaporation core. In this example, a blind hole structure is adopted to seal the microporous tube 381 at this end. This seal prevents the raw water introduced by the raw water pipe 21 from entering the microporous tube 381. The raw water pipe 21, whose end is inserted into the blind hole, has water outlet holes evenly distributed through the tube wall on the part inserted into the blind hole. On the side close to the condensation chamber 351, the end of the microporous tube 381 is inserted therein to form a fixed end of the evaporation core 38, and this side is in close contact with the end face of the capillary material layer 383, so that the capillary material layer 383 with extremely strong water absorption capacity can quickly absorb the water in the inlet structural member 36 into the entire capillary material layer 383. That is, the raw water introduced by the raw water pipe 21 first enters the inlet structural member 36 made of water storage material, and directly enters the capillary material layer through the inlet structural member 36. In addition, in this example, an air outlet duct 362 is provided that passes through the two end surfaces of the inlet structural member 36 to balance the pressure in the condensation chamber 351. The hot steam in the condensation chamber 351 is discharged through the air outlet pipe 22 connected to the air outlet duct 362 to preheat the raw water that has not entered the inlet structural member 36.

[0042] 6 and 7 , the circumferential wall of the outlet structural member 37 is fixedly connected to the shell 35 . The outlet structural member 37 is made of a rigid material and is provided with a nozzle 40 passing through the two end walls. The end of the microporous tube 381 is inserted into one end of the nozzle 40 and fixed. Referring to FIG1 , the other end of the nozzle 40 is connected in parallel with the backwash water pipe 42 and the hot air pipe 43 through a pipeline. The opening and closing of the valves on these pipes can realize the selective connection between the nozzle 40 and each pipe. In addition, the hot exhaust pipe 44 is connected in parallel to the hot air pipe 43 after passing through the purifier 45. In this example, the backwash drain pipe 41 is connected to the outlet 401, and the fresh water outlet pipe 47 is connected to the outlet 402 to introduce the fresh water in the condensation chamber 351 into the fresh water storage tank 48. The insulated electric heating layer wiring 46 is connected to the power supply to supply power to the insulated electric heating layer 382.

[0043] The operating principle of the first embodiment is briefly described as follows: Referring to Figure 1 , when desalinating raw water, the lift pump 13 operates in a timely manner based on the water level in the seawater storage tank 14 to continuously replenish seawater. The relatively high seawater flows through the raw water pipe 21 to the inlet structure 36 and is preheated by the hot steam discharged from the outlet pipe 22 before reaching the inlet structure 36. The seawater then enters the capillary material layer 383 and evaporates due to the heating of the photothermal material layer, the insulating electric heating layer 382, ​​or the hot air or hot exhaust gas passing through the microporous tubes 381. These heating methods can be used simultaneously or selectively depending on the actual situation. For example, during the day, only solar heating can be used, while at night, hot air, hot exhaust gas, heating through the microporous tubes 381, or electrical heating can be used. The evaporated water vapor condenses into fresh water in the condensation chamber 351 and enters the fresh water storage tank 48 through the fresh water outlet pipe 47. When hot air or hot exhaust gas is used to heat capillary material layer 383, a portion of the hot steam is discharged to the atmosphere through outlet duct 362, outlet pipe 22, secondary condensation chamber 23, and pressure relief valve 24 to balance the pressure within condensation chamber 351. When excessive salt accumulates in the capillary material layer and needs to be removed, backwash valve 16 is opened and backwash pump 15 is activated. Seawater enters microporous tube 381 through backwash pipe 42 and is pressurized to flush capillary material layer 383 through the micropores. This causes the salt to escape from capillary material layer 383 along with the seawater and enter condensation chamber 351, where it is then discharged through backwash drain pipe 41, achieving cleanliness. Any remaining fresh water or seawater after backwashing in condensation chamber 351 can be drained through the drain valve located at the lowest position within the condensation chamber. Second embodiment

[0044] The following details only the differences between this example and the first embodiment, and the similarities are not repeated. Referring to Figure 8 , for impure hot gas, hot gas pipe 43, like hot exhaust pipe 44, also passes through purifier 45 before entering microporous tube 381. Furthermore, unlike the previous example, the preheating unit 2 in this example has an outlet pipe 22 that passes through the seawater tank 14. The portion within the seawater tank 14 utilizes a coiled tube to increase the heat dissipation area for the raw water. The coiled tube transfers heat from the hot steam exhausted from the seawater evaporator 3 to the raw water entering the inlet structure 36, thus utilizing the exhausted heat energy. Third embodiment

[0045] The difference between this example and the previous two examples is that the structure of the inlet structural member 36 is different. The inlet structural member 36 is made of different materials in the radial direction. Only the inner ring near the raw water pipe connection end 361 is made of water storage material, while the outer ring is made of high-density rigid material. This can not only meet the requirements of raw water being transferred to the capillary material layer 383, but also relatively improve the strength and service life of the inlet structural member. Fourth embodiment

[0046] The difference between this example and the above examples is that a three-layer capillary material layer structure is used to replace the single capillary material layer 383 in the above examples, and an air-permeable and water-impermeable material layer 3832 and a heat-conducting layer 3831 are set between each layer. The heat-conducting layers 3831 are connected in series with each other. Compared with the single-layer structure, the evaporation surface area of ​​the capillary material layer 383 is relatively expanded. The function of the air-permeable and water-impermeable layer 3832 is to prevent the raw water from interfering with each other between the capillary material layers 383, while the hot steam can pass through directly. Reaching the condensation chamber 351, the function of the heat-conducting layer 3831 is to enable the solar heat and / or hot air and / or electric heat to quickly and evenly reach each capillary material layer 383. It can be made of a perforated metal plate or a metal mesh. Referring to Figure 9, from bottom to top, the first layer is the heat-conducting layer 3831, the capillary material layer 383 and the air-permeable and water-impermeable material layer 3832, and the second and third layers are the same. The composite capillary material made in this way can be wrapped on the microporous tube 381 in the same way as the single-layer capillary material layer 383.

[0047] Referring to Figure 10, for the sake of clarity, the insulating electric heating layer 382 between the microporous tube 381 and the composite capillary material layer is omitted in this figure. In this example, a microporous tube 381 with a rectangular cross-section is used. After the composite capillary material is wrapped around the microporous tube 381, it is then wrapped with a photothermal material layer 384.

[0048] Obviously, the structural form using the composite capillary material layer is also applicable to the seawater evaporator 3 in which the microporous tube 381 is a circular tube. Fifth embodiment

[0049] This example differs from the previous examples in that housing 35 is made of metal, and the photothermal material layer 384 and concentrating reflector 39 are omitted. For areas with short solar insolation, this example eliminates solar-related components and utilizes only hot air or electricity for heating and evaporation. This also offers the advantages of a relatively long lifespan and low cost of a seawater evaporator structure. Sixth embodiment

[0050] The difference between this example and the above examples is that a microporous tube 381 made of molybdenum disilicide as the basic material is used, which has the characteristics of high temperature resistance, oxidation resistance, and low aging resistance heating; or a microporous tube 381 made of lanthanum chromate as the main material component is used, which consumes less energy and can accurately control the temperature, so that the insulating electric heating layer 382 can be eliminated and the microporous tube 381 can be directly energized to evaporate the raw water in the capillary material layer 383. Seventh embodiment

[0051] The difference between this example and the above examples is that the microporous tube 381 is formed as a tube with one end open and the other end sealed, so the raw water pipe connecting end 361 in the inlet structural member 36 can be processed into a through hole, making the processing of the inlet structural member 36 simpler. Eighth embodiment

[0052] Referring to Figure 11 , the seawater desalination device 1000 of the present invention addresses the high demand for fresh water by connecting multiple seawater evaporators 3 in parallel. Specifically, a raw water unit 1 with comparable water supply capacity and a corresponding auxiliary unit 4 are employed. The raw water pipes 21 of the multiple seawater evaporators 3 are connected in parallel to the raw water main pipe 21A, the backwash drain pipe 41 is connected in parallel to the backwash drain main pipe 41A, and the freshwater outlet pipe 47 is connected in parallel to the freshwater outlet main pipe 47A. The pipes connected to the nozzles 40 of each seawater evaporator 3 are also connected in parallel to the main pipe, and can be selectively connected to the backwash water pipe 42, the hot gas pipe 43, and the hot exhaust pipe 44.

Claims

1. A seawater desalination device, comprising a seawater evaporator, wherein the seawater evaporator has a double-layer internal vacuum structure housing, an inlet structure being provided at one end of the housing, and an outlet structure being provided at the opposite end; Its characteristics are: The evaporation core is a tubular body, one end of the tubular body is fixed to the inlet structural member, and the other end is fixed to the outlet structural member. The space between the evaporation core and the shell forms a condensation chamber. The tubular body is radially arranged from the inside to the outside, including a microporous tube and a capillary material layer. The microporous tube is used to backwash the capillary material layer or transfer hot air or hot exhaust gas. The peripheral wall of the microporous tube is uniformly distributed with micropores penetrating the tube wall. The microporous tube is sealed at one end of the inlet structural member. The end of the inlet structural member facing away from the evaporation core is provided with a raw water pipe connection end for introducing seawater into the capillary material layer. The capillary material layer has multiple layers, and an air-permeable and water-impermeable material layer and a heat-conducting layer are provided between adjacent layers. The heat-conducting layer is a perforated metal plate or a metal mesh, and multiple heat-conducting layers are connected in series. The structure of the inlet structural member at least at the raw water connection end is made of a water storage material, and the water storage material is in close contact with the capillary material layer; The outlet structural member is provided with a pipe mouth connected to the microporous tube, and is also provided with a water outlet connected to the inside and outside of the condensation chamber. The pipe mouth is connected to a pipe and the pipe is selectively connected to the backwash water pipe, the hot air pipe or the hot exhaust pipe. The water channel includes a condensate outlet and a backwash outlet.

2. The seawater desalination device according to claim 1, characterized in that: The housing is made of light-transmitting material; In the radial direction, a photothermal material layer is arranged outside the capillary material layer.

3. The seawater desalination device according to claim 2, characterized in that: It also includes a light-collecting reflector plate, which is arranged on the side of the seawater evaporator facing away from sunlight.

4. The seawater desalination device according to claim 1, characterized in that: The microporous tube is made of a material that generates heat when electricity is applied.

5. The seawater desalination device according to claim 1, characterized in that: In the radial direction, an insulating electric heating layer is further provided between the microporous tube and the capillary material layer.

6. The seawater desalination device according to any one of claims 1 to 5, characterized in that: The raw water connection end is a concave pipe hole, the water outlet end of the raw water pipe is inserted into the concave pipe hole, and the peripheral wall of the insertion section of the raw water pipe is provided with evenly distributed water outlet holes.

7. The seawater desalination device according to claim 6, characterized in that: There are multiple seawater evaporators, the raw water connection end is connected to the raw water pipe and then connected in parallel to the raw water main pipe, the outlet is connected to the fresh water outlet pipe and then connected in parallel to the fresh water outlet main pipe, and the pipe mouth is connected to a pipe and then connected in parallel to the main pipe.

8. The seawater desalination device according to claim 7, characterized in that: The inlet structural member is further provided with an air outlet communicating with the inside and outside of the condensation chamber; It also includes a preheating unit for preheating the raw water entering the seawater evaporator. The preheating unit includes an outlet pipe connected to the outlet duct. The outlet pipe transfers the heat in the hot steam exhausted from the seawater evaporator to the raw water to be entered into the inlet structural member.

Images