All-day solar-powered seawater desalination device and method

Abstract

The present invention relates to the technical field of solar-powered seawater desalination. Specifically disclosed are an all-day solar-powered seawater desalination device and method. In the present invention, by means of a prepared composite hydrogel evaporator, water in seawater can be evaporated into water vapor and the water vapor undergoes condensation to become freshwater. By combining solar energy and a long-afterglow noctilucent device, evaporation occurs in the daytime by means of the composite hydrogel evaporator under solar irradiation, and the evaporation process continues at night by means of light energy released by a long-afterglow noctilucent device, so that seawater can be efficiently evaporated both in the daytime and at night, thus achieving continuous seawater desalination. The present invention can realize continuous and efficient evaporation of seawater all day, thereby improving the freshwater yield, achieves efficient utilization of energy by means of dual energy excitation, and uses a low energy consumption and environmentally friendly method to solve the problem of shortage of freshwater resources.

Description

All-weather solar seawater desalination device and method Technical Field

[0001] The present invention relates to the technical field of solar seawater desalination, and in particular to an all-weather solar seawater desalination device and method. Background Art

[0002] As the problem of water shortage intensifies, solar desalination technology has become an important way to obtain freshwater resources. However, existing solar desalination technology has an important limitation, that is, it can only use solar energy for evaporation during the day, but not at night, which limits the efficiency and stability of desalination. Traditional solar desalination technology usually relies on daylight to provide energy for evaporation, so the evaporation efficiency drops significantly at night or on cloudy days. Although there are some methods based on thermal energy storage that can continue evaporation at night, these methods are usually complicated and costly. Therefore, there is an urgent need for an innovative method that can overcome the limitations of existing technologies and achieve efficient solar desalination around the clock.

[0003] Summary of the Invention

[0004] The purpose of the present invention is to provide an all-weather solar seawater desalination device and method to solve the problems existing in the above-mentioned prior art.

[0005] To achieve the above-mentioned objectives, the present invention provides an all-weather solar seawater desalination device, comprising a stand, a placement trough being provided at the top of the stand, a seawater holding trough and a freshwater holding trough being installed in the placement trough, the freshwater holding trough being arranged along the circumference of the seawater holding trough, and a composite hydrogel evaporator being provided in the seawater holding trough; a long afterglow support frame being fixedly installed at the top of the stand, a long afterglow luminous device being installed on the side of the long afterglow support frame close to the placement trough; a transparent cover being provided above the placement trough, the transparent cover being mounted on the long afterglow support frame, and the inner bottom end of the transparent cover extending into the freshwater holding trough.

[0006] Preferably, the transparent cover is a transparent glass cover, and the transparent cover has a conical structure.

[0007] Preferably, the composite hydrogel evaporator comprises a hierarchically stacked water supply layer and an evaporation layer; the water supply layer is a polyacrylamide hydrogel, and the evaporation layer is a polyacrylamide / carbon nanotube coating coated on a qualitative filter paper.

[0008] Preferably, the mass ratio of carbon nanotubes to polyacrylamide in the evaporation layer is 1 to 10:100.

[0009] Preferably, the diameter of the carbon nanotubes in the evaporation layer is 30 nm to 100 nm.

[0010] Preferably, the height ratio of the evaporation layer to the water supply layer is 1:5 to 12.5.

[0011] The present invention also provides a method for preparing an all-weather solar seawater desalination device, comprising the following steps:

[0012] Polyacrylamide hydrogel preparation;

[0013] acrylamide, an initiator ammonium persulfate, a co-initiator tetramethylethylenediamine, a cross-linking agent methylenebisacrylamide and water are mixed and polymerized and cross-linked in a mold to obtain a polyacrylamide hydrogel; the mass ratio of acrylamide, an initiator ammonium persulfate, a co-initiator tetramethylethylenediamine, a cross-linking agent methylenebisacrylamide and water is 10-20: 0.001-0.030: 0.001-0.030: 0.0005-0.0025: 80-120;

[0014] Preparation of polyacrylamide slurry;

[0015] acrylamide, an initiator ammonium persulfate, a co-initiator tetramethylethylenediamine and water are mixed to carry out a polymerization reaction to obtain a polyacrylamide slurry; the mass ratio of acrylamide, an initiator ammonium persulfate, a co-initiator tetramethylethylenediamine and water is 1-3:0.01-0.015:0.01-0.015:78-160;

[0016] Preparation of polyacrylamide / carbon nanotube coating;

[0017] The carbon nanotubes are mixed with the prepared polyacrylamide slurry at a mass ratio of carbon nanotubes to polyacrylamide of 1 to 10:100, and ultrasonically dispersed to prepare a polyacrylamide / carbon nanotube composite solution with a carbon nanotube to polyacrylamide ratio of 2% to 4%, and the prepared composite solution is coated on a qualitative filter paper to obtain a polyacrylamide / carbon nanotube coating;

[0018] Preparation of composite hydrogel evaporator;

[0019] The prepared polyacrylamide / carbon nanotube coating is adhered to the top end surface of the prepared polyacrylamide hydrogel and allowed to stand for 10 to 20 minutes to obtain a composite hydrogel evaporator;

[0020] Preparation of long afterglow luminous device;

[0021] The long afterglow material is mixed with the prepared polyacrylamide slurry to obtain a long afterglow slurry with a mass percentage concentration of 20% to 30% of the long afterglow material, and the long afterglow slurry is coated on a qualitative filter paper and dried naturally to prepare a long afterglow luminous device;

[0022] assembly;

[0023] The stand, the seawater holding tank, the freshwater holding tank, the transparent cover, the long afterglow support frame, the prepared composite hydrogel evaporator and the long afterglow luminous device are assembled to obtain an all-weather solar seawater desalination device.

[0024] Preferably, the long afterglow material is strontium aluminate co-activated by europium and dysprosium.

[0025] Preferably, the polymerization cross-linking reaction and the polymerization reaction are carried out at a temperature of 20° C. to 80° C. and for a time of 1 hour to 3 hours.

[0026] Preferably, the ultrasonic dispersion time is 5 min to 45 min.

[0027] Compared with the prior art, the present invention has the following advantages and technical effects:

[0028] 1. All-weather efficient evaporation: This device achieves efficient all-weather evaporation through dual evaporation methods, using solar energy during the day and long-lasting luminous light at night. Traditional devices are limited by daytime sunlight evaporation, and evaporation efficiency drops significantly at night. This invention overcomes this limitation through the innovative use of long-lasting luminous light, thereby significantly improving the efficiency of seawater desalination.

[0029] 2. Efficient energy utilization: By utilizing two different energy sources, solar energy and long afterglow luminous devices, this device achieves efficient energy utilization at different time periods. During the day, sunlight is used to store energy in the long afterglow luminous devices, while at night, the light energy of the long afterglow luminous devices is released, maximizing energy utilization and improving overall energy utilization efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0031] FIG1 is a schematic structural diagram of an all-weather solar seawater desalination device according to the present invention;

[0032] FIG2 is a schematic structural diagram of a composite hydrogel evaporator according to the present invention;

[0033] Among them: 1. platform; 2. seawater holding tank; 3. fresh water holding tank; 4. composite hydrogel evaporator; 41. water supply layer; 42. evaporation layer; 5. long afterglow support frame; 6. transparent cover. DETAILED DESCRIPTION

[0034] It should be noted that, unless there is a conflict, the embodiments of the present invention and the features of the embodiments may be combined with each other. The embodiments described are only some of the embodiments of the present invention, not all of them. All other embodiments obtained by those of ordinary skill in the art without creative work are within the scope of protection of the present invention. The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with the embodiments.

[0035] The present invention provides an all-weather solar seawater desalination device, comprising a platform 1, a placement trough being provided at the top of the platform 1, a seawater holding trough 2 and a freshwater holding trough 3 being installed in the placement trough, the freshwater holding trough 3 being arranged circumferentially along the seawater holding trough 2, and a composite hydrogel evaporator 4 being provided in the seawater holding trough 2; a long afterglow support frame 5 being fixedly installed at the top of the platform 1, a long afterglow luminous device being installed on the side of the long afterglow support frame 5 close to the placement trough; a transparent cover 6 being provided above the placement trough, the transparent cover 6 being mounted on the long afterglow support frame 5, and the inner bottom end of the transparent cover 6 extending into the freshwater holding trough 3.

[0036] Furthermore, the transparent cover 6 is a transparent glass cover, and the transparent cover 6 is a conical structure.

[0037] Furthermore, the composite hydrogel evaporator 4 includes a hierarchically stacked water supply layer 41 and an evaporation layer 42; the water supply layer 41 is a polyacrylamide hydrogel, and the evaporation layer 42 is a polyacrylamide / carbon nanotube coating coated on a qualitative filter paper.

[0038] Furthermore, the mass ratio of carbon nanotubes to polyacrylamide in the evaporation layer 42 is 1-10:100.

[0039] Furthermore, the diameter of the carbon nanotubes in the evaporation layer 42 is 30 nm to 100 nm.

[0040] Furthermore, the height ratio of the evaporation layer 42 to the water supply layer 41 is 1:5 to 12.5.

[0041] The present invention also provides a method for preparing an all-weather solar seawater desalination device, comprising the following steps:

[0042] Polyacrylamide hydrogel preparation;

[0043] acrylamide, an initiator ammonium persulfate, a co-initiator tetramethylethylenediamine, a cross-linking agent methylenebisacrylamide and water are mixed and polymerized and cross-linked in a mold to obtain a polyacrylamide hydrogel; the mass ratio of acrylamide, an initiator ammonium persulfate, a co-initiator tetramethylethylenediamine, a cross-linking agent methylenebisacrylamide and water is 10-20: 0.001-0.030: 0.001-0.030: 0.0005-0.0025: 80-120;

[0044] Preparation of polyacrylamide slurry;

[0045] acrylamide, an initiator ammonium persulfate, a co-initiator tetramethylethylenediamine and water are mixed to carry out a polymerization reaction to obtain a polyacrylamide slurry; the mass ratio of acrylamide, an initiator ammonium persulfate, a co-initiator tetramethylethylenediamine and water is 1-3:0.01-0.015:0.01-0.015:78-160;

[0046] Preparation of polyacrylamide / carbon nanotube coating;

[0047] The carbon nanotubes are mixed with the prepared polyacrylamide slurry at a mass ratio of carbon nanotubes to polyacrylamide of 1 to 10:100, and ultrasonically dispersed to prepare a polyacrylamide / carbon nanotube composite solution with a carbon nanotube to polyacrylamide ratio of 2% to 4%, and the prepared composite solution is coated on a qualitative filter paper to obtain a polyacrylamide / carbon nanotube coating;

[0048] Preparation of composite hydrogel evaporator 4;

[0049] The prepared polyacrylamide / carbon nanotube coating is adhered to the top end surface of the prepared polyacrylamide hydrogel, and allowed to stand for 10 to 20 minutes to obtain a composite hydrogel evaporator 4;

[0050] Preparation of long afterglow luminous device;

[0051] The long afterglow material is mixed with the prepared polyacrylamide slurry to obtain a long afterglow slurry with a mass percentage concentration of 20% to 30% of the long afterglow material, and the long afterglow slurry is coated on a qualitative filter paper and dried naturally to prepare a long afterglow luminous device;

[0052] assembly;

[0053] The stand 1, the seawater holding tank 2, the freshwater holding tank 3, the transparent cover 6, the long afterglow support frame 5, the prepared composite hydrogel evaporator 4 and the long afterglow luminous device are assembled to obtain an all-weather solar seawater desalination device.

[0054] Furthermore, the long afterglow material is strontium aluminate co-activated by europium and dysprosium.

[0055] Furthermore, the polymerization cross-linking reaction and the polymerization reaction are carried out at a temperature of 20° C. to 80° C. and for a time of 1 hour to 3 hours.

[0056] Furthermore, the ultrasonic dispersion time is 5 min to 45 min.

[0057] Example 1

[0058] 1. Preparation of polyacrylamide hydrogel: Add 30 g of distilled water and 5 g of acrylamide to a 100 mL beaker and stir until completely dissolved. Then, add 0.00025 g of N,N'-methylenebisacrylamide, 0.0025 g of ammonium persulfate, and 0.0025 g of N,N,N',N'-tetramethylethylenediamine, and add an appropriate amount of distilled water to bring the total weight to 50 g. Stir evenly. Pour the mixture into an 80 mm diameter Petri dish and perform polymerization and cross-linking reaction at 25°C for 2 h to obtain a polyacrylamide hydrogel.

[0059] 2. Preparation of polyacrylamide slurry: Add 2g acrylamide, 0.01g ammonium persulfate and 0.01g N, N, N', N'-tetramethylethylenediamine to 38g distilled water, stir evenly, and let the solution polymerize and become viscous at room temperature for 30 minutes. Then add 40g water, stir evenly, and let it stand at 25°C for 30 minutes to obtain polyacrylamide slurry.

[0060] 3. Polyacrylamide / carbon nanotube coating and composite hydrogel evaporator 4: Disperse 1 g of carbon nanotubes in 49 g of polyacrylamide slurry to prepare a polyacrylamide / carbon nanotube composite solution at a ratio of 2% carbon nanotubes to polyacrylamide, and ultrasonicate for 30 minutes to uniformly disperse it; take 0.3 g of the mixed solution and drop it on qualitative filter paper to prepare a polyacrylamide / carbon nanotube coating, which is then adhered to the surface of the polyacrylamide hydrogel prepared in step 1. After standing for 10 minutes, a composite hydrogel evaporator 4 with a diameter of 80 mm, a height of 4 mm, and a coating height of 0.5 mm is obtained.

[0061] 4. Preparation of long afterglow slurry: Mix 10g of long afterglow material with 40g of polyacrylamide slurry to prepare a long afterglow slurry with a concentration of 20%.

[0062] 5. Preparation of long afterglow luminous device: Take 5g of long afterglow slurry and drop it on qualitative filter paper, wait for it to dry naturally to make a long afterglow luminous device.

[0063] 6. Assemble the stand 1, the seawater holding tank 2, the freshwater holding tank 3, the transparent cover 6, the long afterglow support frame 5, the prepared composite hydrogel evaporator 4 and the long afterglow luminous device to obtain an all-weather solar seawater desalination device.

[0064] Example 2

[0065] 1. Preparation of polyacrylamide hydrogel: Add 30 g of distilled water and 4.8 g of acrylamide to a 100 mL beaker and stir until completely dissolved. Then, add 0.00025 g of N,N'-methylenebisacrylamide, 0.0025 g of ammonium persulfate, and 0.0025 g of N,N,N',N'-tetramethylethylenediamine, and add an appropriate amount of distilled water to bring the total weight to 50 g. Stir evenly. Pour the mixture into an 80 mm diameter Petri dish and perform polymerization and cross-linking reaction at 25°C for 2 h to obtain a polyacrylamide hydrogel.

[0066] 2. Preparation of polyacrylamide slurry: Add 1.9 g acrylamide, 0.01 g ammonium persulfate and 0.01 g N, N, N', N'-tetramethylethylenediamine to 38 g distilled water, stir evenly, and let the solution polymerize and become viscous at room temperature for 30 minutes. Then add 40 g water, stir evenly, and let it stand at 25°C for 30 minutes to obtain polyacrylamide slurry.

[0067] 3. Polyacrylamide / carbon nanotube coating and composite hydrogel evaporator 4: Disperse 1.1 g of carbon nanotubes in 49 g of polyacrylamide slurry to prepare a polyacrylamide / carbon nanotube composite solution at a carbon nanotube to polyacrylamide ratio of 2.2%, and ultrasonicate for 30 minutes to uniformly disperse it; take 0.3 g of the mixed solution and drop it on qualitative filter paper to prepare a polyacrylamide / carbon nanotube coating, which is then adhered to the surface of the polyacrylamide hydrogel prepared in step 1. After standing for 10 minutes, a composite hydrogel evaporator 4 with a diameter of 80 mm, a height of 4 mm, and a coating height of 0.5 mm is obtained.

[0068] 4. Preparation of long afterglow slurry: 10.1 g of long afterglow material was mixed with 40 g of polyacrylamide slurry to prepare a long afterglow slurry with a concentration of 20%.

[0069] 5. Preparation of long afterglow luminous device: Take 5.1g of long afterglow slurry and drop it on qualitative filter paper, wait for it to dry naturally to make a long afterglow luminous device.

[0070] 6. Assemble the stand 1, the seawater holding tank 2, the freshwater holding tank 3, the transparent cover 6, the long afterglow support frame 5, the prepared composite hydrogel evaporator 4 and the long afterglow luminous device to obtain an all-weather solar seawater desalination device.

[0071] Example 3

[0072] 1. Preparation of polyacrylamide hydrogel: Add 30 g of distilled water and 5.2 g of acrylamide to a 100 mL beaker and stir until completely dissolved. Then, add 0.00025 g of N,N'-methylenebisacrylamide, 0.0025 g of ammonium persulfate, and 0.0025 g of N,N,N',N'-tetramethylethylenediamine, and add an appropriate amount of distilled water to bring the total weight to 50 g. Stir evenly. Pour the mixture into a Petri dish with a diameter of 80 mm and perform polymerization and cross-linking reaction at 25°C for 2 h to obtain a polyacrylamide hydrogel.

[0073] 2. Preparation of polyacrylamide slurry: Add 2.1 g of acrylamide, 0.01 g of ammonium persulfate and 0.01 g of N, N, N', N'-tetramethylethylenediamine to 38 g of distilled water, stir evenly, and let the solution polymerize and become viscous at room temperature for 30 minutes. Then add 40 g of water, stir evenly, and let it stand at 25°C for 30 minutes to obtain polyacrylamide slurry.

[0074] 3. Polyacrylamide / carbon nanotube coating and composite hydrogel evaporator 4: 1.2 g of carbon nanotubes were dispersed in 49 g of polyacrylamide slurry to prepare a polyacrylamide / carbon nanotube composite solution with a carbon nanotube to polyacrylamide ratio of 2.4%. The solution was ultrasonicated for 30 minutes to uniformly disperse the solution. 0.3 g of the mixed solution was dropped onto qualitative filter paper to prepare a polyacrylamide / carbon nanotube coating, which was then adhered to the surface of the polyacrylamide hydrogel prepared in step 1. After standing for 10 minutes, a composite hydrogel evaporator 4 was obtained, which had a diameter of 80 mm, a height of 4 mm, and a coating height of 0.5 mm.

[0075] 4. Preparation of long afterglow slurry: 10.2 g of long afterglow was mixed with 40 g of polyacrylamide slurry to prepare a long afterglow slurry with a concentration of 20%.

[0076] 5. Preparation of long afterglow luminous device: Take 5.2g of long afterglow slurry and drop it on qualitative filter paper, wait for it to dry naturally to make a long afterglow luminous device.

[0077] 6. Assemble the stand 1, the seawater holding tank 2, the freshwater holding tank 3, the transparent cover 6, the long afterglow support frame 5, the prepared composite hydrogel evaporator 4 and the long afterglow luminous device to obtain an all-weather solar seawater desalination device.

[0078] The all-weather solar seawater desalination device provided by the present invention has the following working principles:

[0079] The composite hydrogel evaporator 4 is floated on seawater and exposed to sunlight during the day. Due to the efficient light-to-heat conversion of the composite hydrogel evaporator 4, the seawater evaporates. The generated water vapor rises and becomes condensed water after encountering the transparent glass cover. The condensed water flows down the transparent glass cover, and fresh water can be collected. The long-afterglow luminous device on the inner wall of the long-afterglow support frame 5 is exposed to sunlight during the day. The electrons in the long-afterglow material are in an excited state with a high energy level. At night, the excited electrons return to the ground state, and the light generated is absorbed by the composite hydrogel evaporator 4, which then desalinates seawater as it does during the day. This achieves a continuous and efficient seawater desalination process 24 hours a day, solving the problem of traditional seawater desalination devices being unable to evaporate efficiently at night, and significantly improving the efficiency and stability of seawater desalination.

[0080] The daytime evaporation rate and the nighttime evaporation total amount were measured using the all-weather solar desalination device obtained in Examples 1 to 3. The results are as follows:

[0081] Table 1 Evaporation rate during the day and evaporation amount at night of seawater desalination equipment

[0082] The daytime evaporation rates in Table 1 were measured during the daytime when the sun was shining. The long afterglow is also exposed to sunlight during the day, and due to the stimulation of sunlight, it continues to emit light after dark. The total nighttime evaporation was measured continuously for 10 hours. As can be seen from Table 1, the total evaporation in 10 hours of nighttime is approximately the same as the evaporation in 2 hours of daytime. This demonstrates that the all-weather solar desalination device of the present invention can significantly improve seawater desalination efficiency.

[0083] The concentrations of sodium ions, magnesium ions, potassium ions, and calcium ions in the seawater before desalination and in the freshwater obtained after desalination were tested. The test results are shown in Table 2:

[0084] Table 2 Concentration of metal ions in ppm before and after seawater desalination in Examples 1 to 3

[0085] It can be seen from Table 2 that the salt removal rate of the water after desalination treatment by the all-weather solar seawater desalination device provided by the present invention reaches 99.9%.

[0086] The above are merely preferred embodiments of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. An all-weather solar desalination device, characterized in that: The invention comprises a stand (1), wherein a placement tank is arranged at the top of the stand (1), a seawater storage tank (2) and a freshwater storage tank (3) are installed in the placement tank, the freshwater storage tank (3) is arranged along the circumference of the seawater storage tank (2), and a composite hydrogel evaporator (4) is arranged in the seawater storage tank (2); a long afterglow support frame (5) is fixedly installed at the top of the stand (1), and a long afterglow luminous device is installed on the side of the long afterglow support frame (5) close to the placement tank; a transparent cover (6) is arranged above the placement tank, the transparent cover (6) is mounted on the long afterglow support frame (5), and the inner bottom end of the transparent cover (6) extends into the freshwater storage tank (3).

2. The all-weather solar desalination device according to claim 1, characterized in that: The transparent cover (6) is a transparent glass cover, and the transparent cover (6) is a conical structure.

3. The all-weather solar desalination device according to claim 1, characterized in that: The composite hydrogel evaporator (4) comprises a water supply layer (41) and an evaporation layer (42) which are stacked in stages; the water supply layer (41) is a polyacrylamide hydrogel, and the evaporation layer (42) is a polyacrylamide / carbon nanotube coating coated on a qualitative filter paper.

4. The all-weather solar desalination device according to claim 3, characterized in that: The mass ratio of the carbon nanotubes to the polyacrylamide in the evaporation layer (42) is 1 to 10:

100.

5. The all-weather solar desalination device according to claim 4, characterized in that: The diameter of the carbon nanotubes in the evaporation layer (42) is 30nm to 100nm.

6. The all-weather solar desalination device according to claim 3, characterized in that: The height ratio of the evaporation layer (42) to the water supply layer (41) is 1:5 to 12.

5.

7. A method for preparing an all-weather solar desalination device according to any one of claims 1 to 6, characterized in that: The following steps are involved: Polyacrylamide hydrogel preparation; acrylamide, an initiator ammonium persulfate, a co-initiator tetramethylethylenediamine, a cross-linking agent methylenebisacrylamide and water are mixed, and a polymerization cross-linking reaction is carried out in a mold to obtain a polyacrylamide hydrogel; Preparation of polyacrylamide slurry; acrylamide, an initiator ammonium persulfate, a co-initiator tetramethylethylenediamine and water are mixed to carry out a polymerization reaction to obtain a polyacrylamide slurry; Preparation of polyacrylamide / carbon nanotube coating; The carbon nanotubes are mixed with the prepared polyacrylamide slurry, and dispersed by ultrasound to prepare a polyacrylamide / carbon nanotube composite solution, and the prepared composite solution is coated on a qualitative filter paper to obtain a polyacrylamide / carbon nanotube coating; Preparation of composite hydrogel evaporator (4); Adhere the prepared polyacrylamide / carbon nanotube coating to the top end surface of the prepared polyacrylamide hydrogel, and after standing, obtain a composite hydrogel evaporator (4); Preparation of long afterglow luminous device; The long afterglow material is mixed with the prepared polyacrylamide slurry to obtain a long afterglow slurry, and the long afterglow slurry is coated on a qualitative filter paper and dried naturally to prepare a long afterglow luminous device; Assembly; The stand (1), the seawater storage tank (2), the freshwater storage tank (3), the transparent cover (6), the long afterglow support frame (5), the prepared composite hydrogel evaporator (4) and the long afterglow luminous device are assembled to obtain an all-weather solar seawater desalination device.

8. The method for preparing the all-weather solar desalination device according to claim 7, characterized in that: The long afterglow material is strontium aluminate co-activated by europium and dysprosium.

9. The method for preparing the all-weather solar desalination device according to claim 7, characterized in that: The temperature of the polymerization cross-linking reaction and the polymerization reaction is 20° C. to 80° C., and the time is 1 h to 3 h.

10. The method for preparing the all-weather solar desalination device according to claim 7, characterized in that: The duration of ultrasonic dispersion is 5 min to 45 min.

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