Efficient solar water production interface and preparation method thereof

Abstract

The invention belongs to the technical field of solar water production, and particularly relates to an efficient solar water production interface and a preparation method thereof. According to the efficient solar water production interface, the paper substrate serves as a substrate for lifting a water evaporation interface, water to be treated is rapidly conveyed to the evaporation interface through the super-hydrophilicity of the paper substrate, the water surface to be treated is separated from the evaporation interface, and heat energy gathering is facilitated; due to the intrinsic property of the metal nanoparticles and the surface plasmon resonance effect related to electron collective oscillation, the absorbed solar energy can be effectively converted into heat energy, and meanwhile, the metal nanoparticles can respond to broadband incident light; the metal nanoparticles, the carbon powder particles and the paper pulp fibers further raise a water evaporation interface, high sunlight absorptivity of the carbon powder particles and high heat yield of the metal nanoparticles are combined, efficient absorption, efficient heat production and efficient water production are achieved, and the water production cost is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of solar water production, and in particular relates to a high-efficiency solar water production interface and a preparation method thereof. Background Art

[0002] The earth has abundant water resources, with seawater covering 71% of the earth's surface, but it cannot be directly used as domestic and drinking water. Freshwater resources only account for 2.5% of the total water resources, of which less than 0.36% is available to humans. As the two major types of seawater desalination technologies, distillation (thermal method) and membrane method, become more mature, they provide new ways to solve the problem of freshwater shortage.

[0003] Among them, low-efficiency distillation, multi-stage flash evaporation and reverse osmosis membrane have gradually developed into the mainstream water production technologies in the world. Generally speaking, low-efficiency distillation has the advantages of energy saving, low seawater pretreatment requirements and high desalinated water quality, but its structure is complex, the heat exchange area and floor space are large, and the cost is extremely high; reverse osmosis membrane has the advantages of low investment and low energy consumption, but the seawater pretreatment process is complex and the equipment maintenance cost is high; multi-stage flash evaporation has the advantages of mature technology, reliable operation and large device output, but the energy consumption is high, resulting in high cost. Summary of the invention

[0004] The purpose of the present invention is to provide a high-efficiency solar energy water production interface and a preparation method thereof. The high-efficiency solar energy water production interface provided by the present invention can produce water at low cost.

[0005] In order to achieve the above object, the present invention provides the following technical solutions:

[0006] The invention provides a high-efficiency solar water-making interface, comprising a paper substrate and a solar light absorption layer loaded on the surface of the paper substrate; the components of the solar light absorption layer include metal nanoparticles, pulp fibers and carbon powder particles.

[0007] Preferably, the thickness of the paper substrate is 1 to 10 cm; the thickness of the solar light absorption layer is 2 to 20 mm.

[0008] Preferably, the metal nanoparticles include one or more of gold nanoparticles, silver nanoparticles and aluminum nanoparticles.

[0009] Preferably, the particle size of the metal nanoparticles is 10 to 50 nm; and the particle size of the carbon powder particles is 0.2 to 5 μm.

[0010] Preferably, the aspect ratio of the pulp fiber is 900 to 1500, and the length is 1 to 50 mm.

[0011] Preferably, the mass ratio of the metal nanoparticles to the pulp fibers is 1-3:300-1200; the mass ratio of the metal nanoparticles to the carbon powder particles is 1-3:150-200.

[0012] Preferably, a water-permeable functional layer is provided between the solar light absorbing layer and the paper substrate; the water-permeable functional layer is gauze or a mesh support.

[0013] Preferably, the water-absorbing substrate also includes fixing; the fixing is bundling; the material used for bundling is nylon thread or fishing line.

[0014] Preferably, the high-efficiency solar water-making interface further includes a paper restraining frame.

[0015] The present invention also provides a method for preparing the high-efficiency solar water-making interface described in the above scheme, comprising the following steps:

[0016] The metal nanoparticles, pulp fibers, carbon powder particles and water are mixed to form a film to obtain a solar light absorption layer;

[0017] The solar light absorbing layer is covered on a paper substrate to obtain the high-efficiency solar water-making interface.

[0018] The present invention provides a high-efficiency solar water-making interface. In the high-efficiency solar water-making interface provided by the present invention, the paper substrate is used as the substrate for raising the water evaporation interface, and the paper substrate uses its super-hydrophilicity to quickly transport the water to be treated to the evaporation interface, and separates the water surface to be treated from the evaporation interface, which is conducive to the accumulation of thermal energy; the metal nanoparticles can effectively convert the absorbed solar energy into thermal energy due to their intrinsic properties and the surface plasmon resonance effect related to the collective oscillation of electrons, and can respond to incident light of a wide band; the metal nanoparticles, carbon powder particles and pulp fibers further raise the water evaporation interface, and combine the high sunlight absorption of the carbon powder particles and the high heat generation of the metal nanoparticles to achieve high-efficiency absorption, high-efficiency heat generation, and high-efficiency water production, thereby reducing the cost of water production.

[0019] The present invention also provides a method for preparing the high-efficiency solar water-making interface described in the above scheme. Based on the hydrophilicity of pulp fibers, the present invention can filter most of the impurities in the water to be evaporated in a low-cost and replaceable manner while separating the liquid surface of the water to be evaporated and the evaporation interface to improve the heat energy concentration, thereby preventing impurities from contaminating the upper solar light absorption and heat-generating layer and ensuring the water-making efficiency. The present invention is based on a nanofiber skeleton loaded with carbon powder particles, and through the porous structure and high optical absorption of the carbon powder particles, the light trapping efficiency and light absorption efficiency of the solar light absorption layer are greatly increased. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. 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 creative work.

[0021] Figure 1 Schematic diagram of mixing metal nanoparticles, pulp fibers, carbon powder particles and water;

[0022] Figure 2 A schematic diagram of the structure of the high-efficiency solar water-making interface provided by the present invention;

[0023] Figure 3 Schematic diagram of the separation between the evaporation interface of water to be treated and the liquid surface of water to be treated;

[0024] Figure 4 A paper substrate formed by interlaced and stacked pulp fibers;

[0025] Figure 5 is a schematic diagram of the structure of the solar energy absorption layer;

[0026] Figure 6 This is a comparison chart of optical absorption of carbon powder particles, metal nanoparticles and the composite of the two;

[0027] Figure numerals: 1 is a mixing container, 2 is a mixed solution, 3 is a stirring rod, 4 is a paper restraining frame, 5 is a solar light absorbing layer, 501 is pulp fiber, 502 is carbon powder particles, 503 is metal nanoparticles, 6 is a storage container for water to be treated, 7 is a paper substrate, 8 is a liquid surface of water to be treated, and 9 is an evaporation interface of water to be treated. DETAILED DESCRIPTION

[0028] The invention provides a high-efficiency solar water-making interface, comprising a paper substrate and a solar light absorption layer loaded on the surface of the paper substrate; the components of the solar light absorption layer include metal nanoparticles, pulp fibers and carbon powder particles.

[0029] The high-efficiency solar water-making interface provided by the present invention comprises a paper substrate; the thickness of the paper substrate is preferably 1 to 10 cm, more preferably 3 cm or 6 cm. The high hydrophilicity of pulp fibers makes the paper substrate highly hydrophilic, thereby ensuring that the water to be evaporated can be continuously transported from the bottom to the surface of the paper substrate, while separating the liquid surface of the water to be evaporated and the evaporation interface to improve the heat energy accumulation, the low-cost replaceable paper substrate can filter most of the impurities in the water to be evaporated, avoiding impurities from contaminating the upper solar light absorption layer, and ensuring the water-making efficiency.

[0030] In the present invention, the water-absorbing base is preferably fixed; the fixing is preferably binding; the binding material is preferably nylon thread or fishing line. The present invention ensures that the structure is stable during use and is easy to replace by fixing the water-absorbing base.

[0031] In the present invention, the high-efficiency solar water-making interface preferably further comprises a paper binding frame. The present invention also achieves the purpose of fixing the paper substrate through the paper binding frame.

[0032] The high-efficiency solar water-making interface provided by the present invention comprises a sunlight absorption layer; the metal nanoparticles preferably comprise one or more of gold nanoparticles, silver nanoparticles and aluminum nanoparticles.

[0033] In the present invention, the particle size of the metal nanoparticles is preferably 10 to 50 nm, more preferably 20 to 35 nm. The absorption of light by metal nanoparticles is greater than the scattering of light, and while achieving wide-band absorption, the absorbed incident light can be efficiently converted into heat required for water evaporation.

[0034] In the present invention, the aspect ratio of the pulp fiber is preferably 900-1500, more preferably 900, 1000, 1200, 1400 or 1500, and the length is preferably 1-50 mm, more preferably 1 mm, 5 mm, 10 mm, 20 mm, 30 mm, 40 mm or 50 mm. The pulp fiber is the same as the pulp fiber of the paper substrate, and also has extremely high hydrophilicity, and can transfer water on the surface of the paper substrate to the upper surface of the solar light absorption layer.

[0035] In the present invention, the mass ratio of the metal nanoparticles to the pulp fibers is preferably 1-3:300-1200, more preferably 1-3:500-1000, and further preferably 2:700-800.

[0036] In the present invention, the particle size of the carbon powder particles is preferably 0.2-5 μm, more preferably 0.5 μm, 1 μm, 1.5 μm, 2 μm, 3 μm, 4 μm or 4.5 μm. The carbon powder particles are black micro-nano substances, which can ensure high efficiency absorption of incident light.

[0037] In the present invention, the mass ratio of the metal nanoparticles to the carbon powder particles is preferably 1-3:150-200, more preferably 1:175-185.

[0038] In the present invention, the thickness of the solar light absorption layer is preferably 2 to 20 mm, more preferably 5 mm, 10 mm, 15 mm or 18 mm.

[0039] In the present invention, a water-permeable functional layer is preferably provided between the solar light absorbing layer and the paper substrate; the water-permeable functional layer is preferably gauze or a mesh support. The solar light absorbing layer is placed on the water-permeable functional layer to ensure that the solar light absorbing layer is not damaged during the replacement of the paper substrate and can be used for a long time.

[0040] The present invention also provides a method for preparing the high-efficiency solar water-making interface described in the above scheme, comprising the following steps:

[0041] The metal nanoparticles, pulp fibers, carbon powder particles and water are mixed to form a film to obtain a solar light absorption layer;

[0042] The solar light absorbing layer is covered on a paper substrate to obtain the high-efficiency solar water-making interface.

[0043] The present invention forms a film by mixing metal nanoparticles, pulp fibers, carbon powder particles and water (referred to as the first mixing) to obtain a solar light absorbing layer. In the present invention, the mass ratio of the carbon powder particles to water is preferably 0.2 to 0.4:1, more preferably 0.25 to 0.35:1.

[0044] In the present invention, the first mixing is preferably stirring mixing; the rotation speed of the stirring mixing is preferably 150 to 800 rpm, more preferably 300 to 500 rpm, and the mixing time is preferably 3 to 20 min, more preferably 8 to 15 min.

[0045] In the present invention, the film forming device is preferably a paper forming frame; and the film forming method is preferably a paper forming method.

[0046] After obtaining the solar light absorption layer, the present invention covers the solar light absorption layer on the paper substrate to obtain the efficient solar water-making interface. In the present invention, the method for preparing the paper substrate is preferably a conventional papermaking method; and the equipment for preparing the paper substrate is preferably a paper forming frame.

[0047] In order to further illustrate the present invention, the scheme of the present invention is described in detail below in conjunction with the accompanying drawings and embodiments, but they should not be understood as limiting the protection scope of the present invention.

[0048] Example 1

[0049] A method for preparing an efficient solar water-making interface, such as Figure 1 to Figure 6 As shown, the following steps are included:

[0050] (1) Commercial pulp with high hydrophilicity is used to prepare a paper base by a conventional papermaking method, and the paper base is bound around with nylon threads or fastened in a paper binding frame.

[0051] (2) Metal nanoparticles with a particle size of 10 to 50 nm, carbon powder particles with a particle size of 0.2 to 5 μm, and commercial paper pulp are stirred in water, and pulled through a paper restraining frame for multiple times to obtain a solar energy absorption layer with a thickness of 2 to 20 mm. Before using the paper restraining frame, a water-permeable gauze or mesh support is placed in the frame;

[0052] (3) The prepared solar light absorption layer fixed on the gauze or mesh support is placed on the paper substrate to obtain a high-efficiency solar water-making interface.

[0053] (4) When working, the high-efficiency solar water-making interface is placed in the evaporator of the liquid to be treated, and the upper surface of the solar light absorption layer is more than 10 mm higher than the surface of the liquid to be treated.

[0054] When working, the highly hydrophilic, low-cost, replaceable paper substrate filters the water to be treated and continuously transports it to the solar energy absorption interface (solar light absorption layer). After the sunlight enters the solar energy absorption interface, it is efficiently absorbed by the pulp fibers and metal nanoparticles loaded with carbon powder particles. The absorbed solar energy is converted into heat energy through the carbon powder particles and metal nanoparticles with efficient heat generation capacity, which is used for solar water evaporation.

[0055] Example 2

[0056] In this embodiment, a 200nm carbon powder particle and six 30nm gold nanoparticles are combined as an example. The six gold nanoparticles are loaded on the carbon powder particle in six directions: up, down, left, right, front and back. The absorption cross section of each wavelength of this structure is as follows: Figure 6 (red line) is shown. At the same time, the response electric field distribution of 400nm wavelength and the relationship between electric field and heat generation power are calculated through this structure. The results show that the heat generation power of one 200nm carbon powder particle combined with six 30nm gold nanoparticles is 11.8582×10 -8 W.

[0057] Comparative Example 1

[0058] This comparative example is basically the same as Example 2, except that this comparative example has only one 200 nm carbon powder particle.

[0059] The absorption cross section of 200nm carbon powder particles at different wavelengths is as follows: Figure 6 (black line), and at the same time, the calculation of the electric field distribution of the response to the 400nm wavelength shows that the heat generation power of a 200nm carbon powder particle is only 5.1857×10 - 8 W.

[0060] Comparative Example 2

[0061] This comparative example is substantially the same as Example 2, except that this comparative example only has 6 30 nm gold nanoparticles.

[0062] The total absorption cross section of 6 30nm gold nanoparticles at each wavelength is as follows Figure 6 (blue line). At the same time, the electric field distribution of the response to a wavelength of 400 nm was calculated. The results showed that due to the small absorption cross section, the heat generation power of the six 30 nm gold nanoparticles was only 2.2852×10 -8 W.

[0063] It can be seen from the above embodiments that the high-efficiency solar water-making interface provided by the present invention realizes high-efficiency absorption, high-efficiency heat generation, and high-efficiency water-making, and reduces the water-making cost by about 10 to 15%.

[0064] Although the above embodiment describes the present invention in detail, it is only a part of the embodiments of the present invention, not all of the embodiments. Other embodiments can be obtained based on this embodiment without creativity, and these embodiments all fall within the protection scope of the present invention.

Claims

1. A highly efficient solar water-making interface, characterized in that: The invention comprises a paper substrate and a solar light absorbing layer loaded on the surface of the paper substrate; the components of the solar light absorbing layer include metal nanoparticles, pulp fibers and carbon powder particles.

2. The high-efficiency solar water-making interface according to claim 1, characterized in that: The thickness of the paper substrate is 1 to 10 cm; the thickness of the solar light absorption layer is 2 to 20 mm.

3. The high-efficiency solar water-making interface according to claim 1, characterized in that: The metal nanoparticles include one or more of gold nanoparticles, silver nanoparticles and aluminum nanoparticles.

4. The high-efficiency solar water-making interface according to claim 1 or 3, characterized in that: The particle size of the metal nanoparticles is 10-50 nm; the particle size of the carbon powder particles is 0.2-5 μm.

5. The high-efficiency solar water-making interface according to claim 1, characterized in that: The aspect ratio of the pulp fiber is 900-1500, and the length is 1-50 mm.

6. The high-efficiency solar water-making interface according to any one of claims 1 to 3, characterized in that: The mass ratio of the metal nanoparticles to the pulp fibers is 1-3:300-1200; the mass ratio of the metal nanoparticles to the carbon powder particles is 1-3:150-200.

7. The high-efficiency solar water-making interface according to claim 1 or 2, characterized in that: A water-permeable functional layer is arranged between the sunlight absorption layer and the paper substrate; the water-permeable functional layer is gauze or a mesh support.

8. The high-efficiency solar water-making interface according to claim 1, characterized in that: The water-absorbing substrate also includes fixing; the fixing is bundling; the material used for bundling is nylon thread or fishing line.

9. The high-efficiency solar water-making interface according to claim 1, characterized in that: The high-efficiency solar water-making interface also includes a paper binding frame.

10. The method for preparing a high-efficiency solar water-making interface according to any one of claims 1 to 9, characterized in that: The following steps are involved: The metal nanoparticles, pulp fibers, carbon powder particles and water are mixed to form a film to obtain a solar light absorption layer; The solar light absorbing layer is covered on a paper substrate to obtain the high-efficiency solar water-making interface.

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