Preparation method and application of solar interface water evaporator
By using a solar interface water evaporator made of diatomaceous earth and paraffin, the problems of high cost and low efficiency in existing technologies are solved, achieving efficient and low-cost water evaporation and improving durability, making it suitable for large-scale water treatment.
Patent Information
- Application Number
- CN202410138046.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2024-01-30
- Publication Date
- 2026-02-17
- Estimated Expiration
- 2044-01-30
AI Technical Summary
Existing solar interface evaporators suffer from high cost, low efficiency, poor durability, and difficulty in large-scale application, especially in resource-limited regions of developing countries.
A solar interface water evaporator is prepared by using diatomaceous earth and paraffin as the main raw materials, through molding, calcination and surface carbonization. The porous structure of diatomaceous earth and the light absorption characteristics of the carbon layer are utilized to improve water evaporation efficiency and reduce costs by simplifying the process.
It achieves high water evaporation efficiency, low cost, excellent corrosion resistance and weather resistance, and is suitable for large-scale application, especially in areas with limited resources.
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Figure CN117964352B_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application belongs to the technical field of water purification, and particularly relates to a preparation method and application of a solar interface water evaporator. BACKGROUND
[0002] The solar interface evaporator is an innovative water purification technology that uses specially designed materials to form a heat-absorbing layer directly on the water surface, thereby improving water evaporation efficiency. This technology concentrates solar heat energy at the interface between liquid and air, causing surface water molecules to evaporate quickly, thereby achieving efficient water purification and freshwater generation. Compared with traditional solar water evaporation systems, the interface evaporator reduces overall system heat loss and required energy input, improving energy conversion efficiency. The low cost and easy deployment of the interface evaporator make it an ideal choice for developing countries and water resource scarce areas, providing a sustainable solution to the global water resource challenge.
[0003] Although the existing solar interface evaporator has significant advantages in the use of renewable energy, it still has some shortcomings. First, many solar interface evaporators rely on expensive materials and complex manufacturing processes, which increases the initial investment cost and limits their popularity in resource-limited areas such as developing countries. Second, in terms of efficiency, the photo-thermal conversion efficiency of some solar interface evaporators is not ideal, resulting in large energy conversion losses and low water evaporation efficiency, which cannot fully utilize solar energy. In addition, some designs have durability and stability problems in actual operation, including mechanical properties and long-term stability, which may reduce their performance when exposed to the natural environment for a long time. Finally, the current solar interface evaporator technology still faces challenges in large-scale application, and further technological innovation and system optimization are needed to meet the demand of large-scale water treatment.
[0004] Therefore, it is urgent to provide a solar interface evaporator with high water evaporation efficiency, and further, the preparation cost of the solar interface evaporator is low, and the processing cycle is short. SUMMARY
[0005] The present application aims to at least solve one of the technical problems existing in the prior art. To this end, the present application proposes a preparation method and application of a solar interface water evaporator. The preparation method described in the present application is low in cost, does not use any modifier, is environmentally friendly, simple to process, short in cycle (24h), simple and efficient in processing, the solar interface water evaporator prepared by the preparation method has high water evaporation efficiency, is prepared from all-inorganic mineral materials, and has better corrosion resistance and weather resistance.
[0006] The preparation process of the solar interface water evaporator, the main component of diatomite is silicon dioxide, which has excellent hydrophilicity, and diatomite has a porous structure and low thermal conductivity. The carbon plating on the surface can efficiently capture sunlight, fully meeting the requirements of the solar interface water evaporator for water transmission, solar energy capture and thermal insulation. The paraffin acts as a binder and pore-forming agent. If paraffin is not used, the product cannot be formed. The printed sample contains paraffin. After the paraffin is burned and lost at high temperature during the calcination process, the occupied pore sites are left. These pore structures, together with the pore structure of diatomite itself, are beneficial to water transmission, solar energy capture and thermal insulation, thereby significantly improving the water evaporation efficiency of the solar interface water evaporator.
[0007] The first aspect of the present application is a preparation method of a solar interface water evaporator.
[0008] Specifically, the preparation method of the solar interface water evaporator comprises the following steps:
[0009] The paraffin and diatomite are mixed and heated to obtain a mixture, then the mixture is placed in a mold for compression molding to obtain a pre-pressed sample, then a printed mold containing pores is placed on the pre-pressed sample for compression printing to obtain a printed sample, and then the printed sample is calcined to obtain a porous ceramic with one side printed. The porous ceramic with one side printed is placed with the printed side facing up for carbon plating on the surface to obtain the solar interface water evaporator.
[0010] Preferably, the paraffin is a commercially available conventional paraffin, and further preferably 58# paraffin.
[0011] Preferably, the diatomite is in powder form.
[0012] Preferably, the mass ratio of the paraffin to the diatomite is (4-8):10, and further preferably (6-7):10. If the content of paraffin is too high, it will leak during compression, and if the content of paraffin is too low, the printed sample will not have enough pores and will be difficult to form.
[0013] Preferably, the heating temperature is 110-125℃, and the heating time is 40-60 minutes, and further preferably the heating temperature is 118-120℃, and the heating time is 40-60 minutes.
[0014] Preferably, the mixture is taken out and stirred for 20-30 seconds every 10-20 minutes during the heating process. This is to make the mixture more uniform.
[0015] Preferably, the compression molding pressure is 5-12 MPa, and the compression molding time is 30-120 seconds.
[0016] Preferably, the printed mold containing pores is a metal soft mesh with an inner hole size of (2-3)mm*(5-6)mm.
[0017] Preferably, the pressure of the die printing is 1.5-2 MPa, and the time of the die printing is 30-60 seconds.
[0018] Preferably, the temperature of the calcination is 900-1050℃, and the time of the calcination is 0.5-1 hour.
[0019] Preferably, the rate of the temperature rise during the calcination is 8-10℃ / min.
[0020] Preferably, the calcination is performed in a muffle furnace.
[0021] Preferably, the process of the surface carbon plating is placing the printed side upward on the outer flame of a candle for heating. The purpose of the surface carbon plating is to form a carbon layer, which is a light absorption layer of the solar interface water evaporator.
[0022] Further preferably, the printed side is placed upward on the outer flame of a candle for heating for 45-180 seconds, further preferably for 1-1.5 minutes.
[0023] The second aspect of the present application is a solar interface water evaporator.
[0024] Specifically, the solar interface water evaporator is prepared by the above preparation method.
[0025] Preferably, the solar interface water evaporator comprises a carbon layer and a porous ceramic under the carbon layer.
[0026] The third aspect of the present application is an application of the preparation method of the solar interface water evaporator.
[0027] Specifically, the application of the preparation method of the solar interface water evaporator is in the field of water evaporation.
[0028] Compared with the prior art, the present application has the following beneficial effects:
[0029] (1) In the preparation process of the solar interface water evaporator, the main component of diatomite is silicon dioxide, which has excellent hydrophilicity. The diatomite has a porous structure and low thermal conductivity, and can efficiently capture sunlight through surface carbon plating, fully meeting the requirements of the solar interface water evaporator for water transmission, solar energy capture, and heat insulation. If paraffin is not used, the product cannot be formed. The paraffin in the printed sample is burned and lost at high temperature during the calcination process, and the occupied pore sites are left. These pore structures, together with the pore structure of diatomite itself, are beneficial to water transmission, solar energy capture, and heat insulation, thereby significantly improving the water evaporation efficiency of the solar interface water evaporator, for example, the water evaporation rate is not less than 1.61 kgm -2 h -1 .
[0030] (2) The application provides a preparation method and application of a solar interface water evaporator. The preparation method is low in cost, does not use any modifier, is environmentally friendly, simple in processing, short in cycle (not more than 24 h, or even not more than 4 h), simple and efficient in processing, high in water evaporation efficiency of the solar interface water evaporator prepared by the preparation method, and prepared from all-inorganic mineral materials, and is excellent in corrosion resistance and weather resistance. BRIEF DESCRIPTION OF DRAWINGS
[0031] Figure 1 A metal soft net map for a mold pressing mold;
[0032] Figure 2 An SEM map of the porous ceramic with printing prepared in Example 1;
[0033] Figure 3 A water absorption demonstration map of the porous ceramic with printing prepared in Example 1;
[0034] Figure 4 A solar interface water evaporator map prepared in Example 1;
[0035] Figure 5 A map of the solar interface water evaporation mass per unit area of the solar interface water evaporator prepared in Example 1 changing with time. DETAILED DESCRIPTION
[0036] In order to make the skilled in the art more clearly understand the technical solutions of the application, the following examples are used for illustration. It should be pointed out that the following examples do not constitute a limitation on the scope of protection required by the application.
[0037] The raw materials, reagents or devices used in the following examples can be obtained from conventional commercial channels or can be obtained by existing known methods, unless otherwise specified.
[0038] The 58# paraffin used in the following examples is a section paraffin provided by the McKinley Company, and the melting point is 58-60°C.
[0039] The diatomite powder is provided by Tianjin Chihyuan Company.
[0040] The metal soft net with an inner hole size of 3mm*6mm is provided by Dongyun Aluminum Net Company.
[0041] Example 1: Preparation method of a solar interface water evaporator
[0042] A preparation method of a solar interface water evaporator, comprising the following steps:
[0043] First, 6 grams of 58# paraffin and 10 grams of diatomite powder are poured into a 250-milliliter glass bottle, and preliminary mixing is performed by simple stirring. Next, the glass bottle is placed in an oven with a preset temperature of 120°C, and heating is performed for 1 hour. During this process, the contents of the glass bottle are taken out every 20 minutes and stirred for 30 seconds to ensure uniform mixing. Subsequently, 1 gram of the mixture is placed in a mold, and molding is performed using a pressure of 10 MPa, which is maintained for 1 minute to produce a pre-pressed sample. Next, a metal soft mesh with an inner hole size of 3x6 millimeters is used as a printing mold, which is placed on the pre-pressed sample, and molding is performed again using a pressure of 2 MPa, which is also maintained for 1 minute. The printed sample is then transferred to a muffle furnace, heated to 1000°C at a heating rate of 10°C / minute, and held for 1 hour to complete calcination (or sintering), thereby obtaining a porous ceramic with a print. Finally, the calcined porous ceramic with a print is placed face up on the outer flame of a candle and heated for 1 minute (this step is surface carbon plating, i.e., preparation of a light-absorbing layer), thereby producing a solar interface water evaporator.
[0044] Example 2: Method for producing a solar interface water evaporator
[0045] A method for producing a solar interface water evaporator includes the following steps:
[0046] First, 6 grams of 58# paraffin and 10 grams of diatomite powder are poured into a 250-milliliter glass bottle, and preliminary mixing is performed by simple stirring. Next, the glass bottle is placed in an oven with a preset temperature of 120°C, and heating is performed for 1 hour. During this process, the contents of the glass bottle are taken out every 20 minutes and stirred for 30 seconds to ensure uniform mixing. Subsequently, 1 gram of the mixture is placed in a mold, and molding is performed using a pressure of 10 MPa, which is maintained for 1 minute to produce a pre-pressed sample. Next, a metal soft mesh with an inner hole size of 3x6 millimeters is used as a printing mold, which is placed on the pre-pressed sample, and molding is performed again using a pressure of 2 MPa, which is also maintained for 1 minute. The printed sample is then transferred to a muffle furnace, heated to 1000°C at a heating rate of 10°C / minute, and held for 1 hour to complete calcination (or sintering), thereby obtaining a porous ceramic with a print. Finally, the calcined porous ceramic with a print is placed face up on the outer flame of a candle and heated for 1 minute (this step is surface carbon plating, i.e., preparation of a light-absorbing layer), thereby producing a solar interface water evaporator.
[0047] Example 3: Method for producing a solar interface water evaporator
[0048] A method for producing a solar interface water evaporator includes the following steps:
[0049] First, 9 grams of 58# paraffin and 10 grams of diatomite powder are poured into a 250-milliliter glass bottle, and preliminary mixing is performed by simple stirring. Next, the glass bottle is placed in an oven with a preset temperature of 150°C, and heating is performed for 1 hour. During this process, the contents of the glass bottle are taken out every 20 minutes and stirred for 30 seconds to ensure uniform mixing. Subsequently, 1 gram of the mixture is placed in a mold, and molding is performed using a pressure of 8 MPa, which is maintained for 1 minute to produce a pre-pressed sample. Next, a metal soft mesh with an inner hole size of 3 x 6 millimeters is used as a printing mold, which is placed on the pre-pressed sample and subjected to printing molding by applying a pressure of 2 MPa for 1 minute. The printed sample is then transferred to a muffle furnace, heated to 950°C at a heating rate of 9°C / minute, and held at this temperature for 1 hour to complete calcination (or sintering), thereby obtaining a porous ceramic with printing. Finally, the calcined porous ceramic with printing is placed face up on the outer flame of a candle and heated for 2 minutes to perform surface carbon plating, i.e., to prepare a light-absorbing layer, thereby producing a solar interface water evaporator.
[0050] Comparative Example 1
[0051] Comparative Example 1 differs from Example 1 only in that an equal amount of PEG (polyethylene glycol) is used instead of 58# paraffin in Example 1, and the other processes are the same as in Example 1.
[0052] Comparative Example 2
[0053] Comparative Example 2 differs from Example 1 only in that an equal amount of beeswax is used instead of 58# paraffin in Example 1, and the other processes are the same as in Example 1.
[0054] Comparative Example 3
[0055] Comparative Example 3 differs from Example 1 only in that an equal amount of micron-sized silicon dioxide powder is used instead of diatomite powder in Example 1, and the other processes are the same as in Example 1.
[0056] Comparative Example 4
[0057] Comparative Example 4 differs from Example 1 only in that the process of surface carbon plating is omitted, and the other processes are the same as in Example 1.
[0058] Comparative Example 5
[0059] Comparative Example 5 differs from Example 1 only in that the calcination process is performed by heating to 850°C at a heating rate of 5°C / minute and holding at this temperature for 1 hour to complete calcination, and the other processes are the same as in Example 1.
[0060] Product Effect Test
[0061] Figure 1 The molding mold is a metal soft mesh pattern.Figure 2 SEM image of the porous ceramic with printing prepared in Example 1, from Figure 2 It can be seen that the porous ceramic has a rich porous structure inside; Figure 3 Water absorption demonstration image of the porous ceramic with printing prepared in Example 1, from Figure 3 It can be seen that the water absorption of the porous ceramic has a fast water absorption rate; Figure 4 Solar interface water evaporation device prepared in Example 1; Figure 5 Solar interface water evaporation device prepared in Example 1, the water evaporation mass per unit area of the solar interface water evaporation device changes with time.
[0062] 1. Water evaporation performance test
[0063] Water evaporation performance test method: pour seawater into a glass cup, and place the solar interface water evaporation devices prepared in the examples and comparative examples on the liquid surface of the seawater in the glass cup, use a xenon lamp as a simulated sunlight source, use an irradiation intensity of one solar intensity (1000w / m 2 ) to test the water evaporation performance, and the test results are shown in Table 1.
[0064] Table 1
[0065] Water evaporation rate (kgm -2 h -1 )]]> Example 1 1.61 Example 2 1.58 Example 3 1.60 Comparative Example 1 1.35 Comparative Example 2 1.37 Comparative Example 3 1.48 Comparative Example 4 0.85 Comparative Example 5 1.47
[0066] It can be seen from Table 1 that the solar interface water evaporation device prepared in the examples has a higher water evaporation efficiency compared with Comparative Examples 1-5, and thus it can be seen that the selection of raw materials, carbon plating and calcination parameters in the preparation process of the solar interface water evaporation device have a significant influence on the water evaporation rate of the prepared solar interface water evaporation device.
[0067] 2. Corrosion resistance test
[0068] Take the solar interface water evaporation device prepared in Example 1, and sequentially immerse it in 1M hydrochloric acid and 1M sodium hydroxide aqueous solution for 3 days. Then, take out and observe the solar interface water evaporation device, and no change in appearance of the solar interface water evaporation device occurs. Perform water evaporation performance test on the solar interface water evaporation device after immersion, and the results show that the water evaporation rate of the solar interface water evaporation device after immersion in 1M hydrochloric acid is maintained at 1.60-1.62kgm -2 h -1 , and the water evaporation rate of the solar interface water evaporation device after immersion in the sodium hydroxide aqueous solution is maintained at 1.59-1.63kgm -2 h -1 .
[0069] 3. Three-point bending test
[0070] The solar interface water evaporator prepared in Example 1 was subjected to three-point bending test to characterize its mechanical properties, and the bending strength was obtained from the following formula: three-point bending strength (MPa) = 1.5*span*maximum force / width / thickness / thickness. The bending strength of the solar interface water evaporator prepared in Example 1 was measured to be 10.1 MPa, which was significantly better than common evaporator substrates such as aerogels, cellulose, foams, etc.
Claims
1. A method for preparing a solar interface water evaporator, characterized in that, The preparation method comprises the following steps: The paraffin and diatomite are mixed and heated to obtain a mixture, and then the mixture is placed in a mold for compression molding to obtain a pre-pressed sample, then a printing mold containing holes is placed on the pre-pressed sample for compression printing to obtain a printed sample, and then the printed sample is calcined to obtain a porous ceramic with one side printed, and the side with the print is plated with carbon to obtain the solar interface water evaporator. The mass ratio of the paraffin to the diatomite is (4-8):
10. The calcination temperature is 900-1050℃, and the calcination time is 0.5-1 hour.
2. The production method according to claim 1, characterized by, The paraffin is 58# paraffin; and / or the diatomite is in the form of powder.
3. The production method according to claim 1, characterized by, The heating temperature is 110-125℃, and the heating time is 40-60 minutes.
4. The method of claim 1, wherein, The compression molding pressure is 5-12MPa, and the compression molding time is 30-120 seconds.
5. The preparation method according to claim 1, characterized in that, The printing mold containing holes is a metal soft net with an inner hole size of (2-3)mm*(5-6)mm.
6. The method of any one of claims 1-5, wherein, The process of the surface carbon plating is that the side with the print is placed upward on the outer flame of a candle for heating.
7. A solar interface water evaporator characterized by, The solar interface water evaporator is prepared by the preparation method in any one of claims 1-6, and comprises a carbon layer and a porous ceramic layer under the carbon layer.
8. Application of the solar interface water evaporator prepared by the preparation method in any one of claims 1-6 in the field of water evaporation.
Citation Information
Patent Citations
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