Alkali-resistant solar interfacial evaporation material for aquaculture wastewater treatment and preparation method thereof

Abstract

The application discloses an alkali-resistant solar interfacial evaporation material for aquaculture sewage treatment and a preparation method thereof, and relates to the field of energy and environmental materials.The method comprises the following steps: S1, mixing clay and iron powder, stirring, adding water, and then performing rolling and molding, and then calcining to obtain an iron-containing modified clay framework; S2, uniformly mixing attapulgite, montmorillonite, composite alkali-resistant modified plant fiber, and Portland cement with water, and then spraying the mixture on the framework to form a heat insulation and water conveying layer at room temperature; and S3, uniformly mixing carbon black, attapulgite, Portland cement, and composite alkali-resistant modified plant fiber with water, and then spraying the mixture on the heat insulation and water conveying layer to form a heat absorption and evaporation layer at room temperature.The material has good alkali resistance and stability, high solar evaporation efficiency, and can simultaneously remove heavy metals, and has low raw material cost, simple preparation process, and is suitable for the large-scale treatment of aquaculture sewage.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of energy and environmental materials, in particular to an alkali-resistant solar interfacial evaporation material for aquaculture wastewater treatment and a preparation method thereof. BACKGROUND

[0002] Solar interfacial evaporation technology has broad application prospects in seawater desalination and wastewater purification fields relying on clean and renewable energy. The core of the technology is to convert solar energy into heat energy through photo-thermal materials to drive interfacial water evaporation and achieve solid-liquid separation. In aquaculture wastewater treatment, although this technology can remove organic matter, ammonia nitrogen and part of heavy metals in water, the existing evaporation materials lack adaptability. Most of them are based on synthetic polymers or biomass, which have a certain photo-thermal conversion efficiency, but they are difficult to withstand the weak alkaline environment formed during the conventional pretreatment in the aquaculture wastewater treatment process. The pretreatment first removes suspended impurities in the water through flocculation treatment, and then adds calcium hydroxide for neutralization adjustment to stabilize water quality. Long-term soaking of the material can cause structural swelling and degradation, resulting in decreased water transport capacity and evaporation efficiency, limiting its long-term application.

[0003] To improve the stability of the material, some studies use inorganic materials to construct the evaporation substrate. Clay-based materials are concerned due to their wide sources and low cost. However, traditional clay materials have obvious shortcomings. The pore structure of pure clay skeleton is single, making it difficult to balance water transport rate and heat insulation performance, which easily causes heat conduction loss to the water body. In addition, the surface has weak light absorption capacity, which requires additional loading of photo-thermal components. The existing modification schemes mostly achieve functionalization by simply mixing photo-thermal materials. Due to the insufficient bonding force between clay and photo-thermal components, the coating is easy to fall off under the action of water flow and pollutant attachment. Moreover, the materials are not optimized for suspended impurities and chemical corrosion in aquaculture wastewater, resulting in short service life and unstable purification effect.

[0004] The existing solar interfacial evaporation materials also have practical defects. Some high-performance materials rely on high-priced raw materials and require complex preparation processes, which are costly and difficult to meet the economic needs of large-scale aquaculture. Some materials can control costs, but they ignore structural and functional design. For example, a single coating cannot simultaneously achieve efficient light absorption, rapid water transport, and heat insulation. In addition, most materials lack adsorption capacity for heavy metal ions in aquaculture wastewater, and can only evaporate water, which cannot remove pollutants simultaneously. Therefore, it is necessary to develop a photo-thermal coating composite material for solar interfacial evaporation and a preparation method thereof. SUMMARY

[0005] Therefore, the present application aims to provide a light-heat coating composite material for solar interface evaporation and a preparation method thereof, which effectively solves the problems of poor alkali resistance, insufficient long-term stability, and difficulty in simultaneously achieving efficient light absorption, water transport, heat insulation, and heavy metal adsorption of existing solar interface evaporation materials in aquaculture wastewater treatment.

[0006] The present application can achieve the above-mentioned purposes by the following technical solutions: the present application provides a preparation method of an alkali-resistant solar interface evaporation material for aquaculture wastewater treatment, which comprises the following preparation steps: S1: mixing clay and iron powder, stirring and rolling with water to a uniform plastic state to form a formable blank, pressing and forming, calcining and modifying to obtain an iron-containing modified clay framework; S2: mixing attapulgite, montmorillonite, composite alkali-resistant modified plant fiber, silicate cement, and water uniformly into a mud-like state, spraying a coating layer on the surface of the iron-containing modified clay framework, and after solidification at room temperature, forming a heat-insulating water transport layer; S3: mixing carbon black, attapulgite, silicate cement, composite alkali-resistant modified plant fiber, and water uniformly into a mud-like state, spraying a coating layer on the surface of the heat-insulating water transport layer, and after solidification at room temperature, forming a solar interface heat-absorbing evaporation layer, and finally obtaining an alkali-resistant solar interface evaporation material for aquaculture wastewater treatment.

[0007] Further, the composite alkali-resistant modified plant fiber is prepared by the following method: placing jute fiber in an epoxy-silane ethanol solution, taking it out after soaking, drying, then immersing it in an epoxy resin acetone solution, immersing and treating at room temperature, taking it out and solidifying at room temperature to obtain alkali-resistant modified jute fiber, mixing the alkali-resistant modified jute fiber with bamboo fiber uniformly to obtain composite alkali-resistant modified plant fiber.

[0008] Further, the specific preparation method of the composite alkali-resistant modified plant fiber is as follows: cutting the jute fiber to a length of 3-5 mm, soaking it in an epoxy-silane ethanol solution at 50-60 DEG C for 1.5-2 h, taking it out and drying it in an oven at 80-90 DEG C for 1-1.5 h; then immersing the dried jute fiber in an epoxy resin acetone solution at room temperature for 30-45 min, taking it out and draining the excess solution, and continuing to solidify at room temperature in a ventilated environment for 24-36 h to obtain alkali-resistant modified jute fiber; finally, taking the alkali-resistant modified jute fiber and bamboo fiber with a length of 1.5-2 mm by weight fraction, placing them in a high-speed blender and stirring at a speed of 1000 rpm for 5-10 min until they are mixed uniformly to obtain composite alkali-resistant modified plant fiber.

[0009] Further, the raw materials of the composite alkali-resistant modified plant fiber are as follows in terms of weight fraction: 10-20 parts of alkali-resistant modified jute fiber, and 80-90 parts of bamboo fiber; wherein the raw materials for preparing the alkali-resistant modified jute fiber are as follows in terms of weight fraction: 10-20 parts of jute fiber, 300-500 parts of an epoxy silane ethanol solution, and 300-500 parts of an epoxy resin acetone solution.

[0010] Further, the epoxy silane in the epoxy silane ethanol solution is γ-glycidoxypropyltrimethoxysilane, and the mass fraction of the γ-glycidoxypropyltrimethoxysilane in the solution is 3%-5%.

[0011] Further, the epoxy resin in the epoxy resin acetone solution is bisphenol A type epoxy resin, the mass fraction of the bisphenol A type epoxy resin in the solution is 8%-12%, and the solvent is acetone.

[0012] Further, the raw materials in S1 are as follows in terms of weight fraction: 90-95 parts of clay, 2-6 parts of iron powder, and 15-20 parts of deionized water.

[0013] Further, in the calcination modification of S1, the temperature is first increased to 200-400℃ at a rate of 5-8℃ / min, and then maintained for 2-3h, then the temperature is increased to 600-900℃ at a rate of 3-5℃ / min, and then maintained for 1.5-2h, and finally the temperature is increased to 900-1100℃ at a rate of 2-3℃ / min, and then maintained for 3-4h, and then the kiln is cooled to room temperature.

[0014] Further, the raw materials in S2 are as follows in terms of weight fraction: 60-65 parts of attapulgite, 15-20 parts of montmorillonite, 5-8 parts of the composite alkali-resistant modified plant fiber, 10-15 parts of Portland cement, and 40-50 parts of deionized water; the spraying thickness is 1000-1500μm, the room temperature solidification temperature is 18-25℃, the solidification time is 52-72h, and deionized water is sprayed 1-2 times per day during the period.

[0015] Further, the Portland cement is 425# Portland cement.

[0016] Further, the particle size of the attapulgite is 200 mesh.

[0017] Further, the particle size of the carbon black is 2000 mesh.

[0018] Further, the raw materials in the S3 are as follows in terms of weight parts: 5-8 parts of carbon black, 45-50 parts of attapulgite, 18-22 parts of silicate cement, 12-18 parts of composite alkali-resistant modified plant fiber, and 30-40 parts of deionized water; the spraying thickness is 200-500 mu m, the room temperature solidification temperature is 18-25 DEG C, and the solidification time is 46-68 hours, during which deionized water is sprayed 1-2 times a day.

[0019] In another aspect, the present application provides an alkali-resistant solar interfacial evaporation material for aquaculture wastewater treatment, which is prepared by the above preparation method.

[0020] The present application has the following advantages: 1. The present application modifies jute fiber by double alkali resistance, and combines with high-temperature calcined modified clay skeleton to build a stable structure system suitable for the weak alkaline environment of aquaculture wastewater, which can effectively prevent the coating from falling off, the skeleton from cracking or the performance from decaying after long-term soaking, and significantly prolong the service life of the material in the aquaculture wastewater treatment scene.

[0021] 2. The present application adopts a layered coating design, and the heat insulation and water conveying layer relies on the layered structure of attapulgite and montmorillonite to realize efficient water conveying and heat insulation, and the solar interfacial heat absorption and evaporation layer relies on high light absorption carbon black to realize efficient light-heat conversion, while the composite alkali-resistant modified plant fiber and clay skeleton cooperate to improve the adsorption capacity of heavy metal ions, so that water evaporation and pollutant removal can be completed simultaneously, without the need for additional purification process, simplifying the aquaculture wastewater treatment process.

[0022] 3. The raw materials used in the present application are natural or commonly used industrial materials with wide sources and low prices, and the preparation process does not require complex and precise equipment, but only needs common processes such as mixing, calcination and spraying, which can not only control the production cost, but also facilitate batch production, meeting the economic and practical needs of large-scale aquaculture scenes for wastewater treatment materials. DETAILED DESCRIPTION

[0023] The technical solutions in the embodiments of the present application will be described below in a clear and complete manner. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0024] In the embodiments of the present application, the montmorillonite is purchased from Jiangsu Bosite Chemical Technology Co., Ltd.

[0025] In the embodiments of the present application, the bisphenol A type epoxy resin is E-51 bisphenol A epoxy resin, which is purchased from Wuxi Xihua Chemical Technology Co., Ltd.

[0026] In the embodiments of the present application, the clay is yellow clay, which is purchased from Lingshou County Jiaying Mineral Products Co., Ltd.

[0027] The iron powder in the embodiment of the application is primary reduced iron powder, and the particle size is 200 mesh, which is purchased from Quanfeng Mineral Product Processing Factory in Lingshou County.

[0028] The preparation method of the alkali-resistant solar interface evaporation material for aquaculture wastewater treatment comprises the following preparation steps: preparation of the composite alkali-resistant modified plant fiber: 10 parts of jute fiber with a length of 3 mm are placed in 300 parts of a mass fraction of 3% γ-glycidoxypropyltrimethoxysilane ethanol solution, and soaked at 50℃ for 1.5 h, and then taken out and dried in an 80℃ oven for 1 h; then the dried jute fiber is immersed in an 8% mass fraction of epoxy resin acetone solution, and soaked at room temperature for 30 min, and then taken out and drained the excess solution on the surface, and then continuously cured at room temperature for 24 h in a ventilated environment to obtain alkali-resistant modified jute fiber; finally, 10 parts of the alkali-resistant modified jute fiber and 80 parts of bamboo fiber with a length of 1.5 mm are put into a high-speed blender and stirred at a speed of 1000 rpm for 5 min until they are uniformly mixed to obtain the composite alkali-resistant modified plant fiber.

[0029] S1: 90 parts of yellow clay and 2 parts of 200 mesh primary reduced iron powder are mixed, 15 parts of deionized water is added, and stirring and rolling are performed to form a formable blank in a uniform plastic state, and the blank is pressed and formed, and then calcination modification is performed; during calcination, the temperature is first increased to 200℃ at a rate of 5℃ / min and kept for 2 h, then increased to 600℃ at a rate of 3℃ / min and kept for 1.5 h, and finally increased to 900℃ at a rate of 2℃ / min and kept for 3 h, and then the kiln is cooled to room temperature to obtain an iron-containing modified clay framework; S2: 60 parts of 200 mesh attapulgite, 15 parts of montmorillonite, 5 parts of composite alkali-resistant modified plant fiber, 10 parts of 425# portland cement and 40 parts of deionized water are uniformly mixed to form a mixture in the form of mud, and the mixture is sprayed on the surface of the iron-containing modified clay framework with a spraying thickness of 1000 μm; room temperature solidification is performed at 18℃, and the solidification time is 52 h, and deionized water is sprayed once a day during the period to form a heat-insulating water conveying layer; S3: 5 parts of 2000 mesh carbon black, 45 parts of 200 mesh attapulgite, 18 parts of 425# portland cement, 12 parts of composite alkali-resistant modified plant fiber and 30 parts of deionized water are uniformly mixed to form a mixture in the form of mud; the surface of the framework on which the heat-insulating water conveying layer is prepared is wetted with water, and the mixture in the form of mud is sprayed on the surface of the heat-insulating water conveying layer by using a paint spraying machine, and the spraying thickness is 200 μm; room temperature solidification is performed at 18℃, and the solidification time is 46 h, and deionized water is sprayed once a day during the period to form a solar interface heat-absorbing evaporation layer, and finally the alkali-resistant solar interface evaporation material for aquaculture wastewater treatment is obtained.

[0030] Embodiment 2: A preparation method of an alkali-resistant solar interfacial evaporation material for aquaculture wastewater treatment, comprising the following preparation steps: preparation of composite alkali-resistant modified plant fiber: 15 parts of jute fiber with a length of 4 mm are placed in 400 parts of a mass fraction of 4% γ-glycidoxypropyltrimethoxysilane ethanol solution, soaked at 55°C for 1.75 h, and then taken out and dried in an oven at 85°C for 1.25 h; then the dried jute fiber is immersed in a mass fraction of 10% epoxy resin acetone solution, immersed at room temperature for 37.5 min, and then taken out and drained of excess surface solution, and then continuously cured at room temperature for 30 h in a ventilated environment to obtain alkali-resistant modified jute fiber; finally, 15 parts of alkali-resistant modified jute fiber and 85 parts of bamboo fiber with a length of 1.75 mm are taken, placed in a high-speed blender, and stirred at a speed of 1000 rpm for 7.5 min to obtain a composite alkali-resistant modified plant fiber.

[0031] S1: 92 parts of yellow clay and 4 parts of 200 mesh primary reduced iron powder are mixed, 18 parts of deionized water is added, and stirring and rolling are performed to form a formable blank in a uniform plastic state. After the blank is pressed and formed, calcination modification is performed. During calcination, the temperature is first increased to 300°C at a rate of 6°C / min, maintained for 2.5 h, then increased to 750°C at a rate of 4°C / min, maintained for 2 h, and finally increased to 980°C at a rate of 2°C / min, maintained for 3.5 h. The kiln is then cooled to room temperature to obtain an iron-containing modified clay framework; S2: 62 parts of 200 mesh attapulgite, 17 parts of montmorillonite, 6.5 parts of composite alkali-resistant modified plant fiber, 12 parts of 425# portland cement, and 45 parts of deionized water are mixed uniformly to form a slurry to obtain a mixture. The mixture is sprayed onto the surface of the iron-containing modified clay framework with a spraying thickness of 1250 μm. The mixture is solidified at room temperature in an environment of 21°C for 62 h, and deionized water is sprayed once a day during the solidification process to form a heat-insulating water-conveying layer; S3: 6.5 parts of 2000 mesh carbon black, 47 parts of 200 mesh attapulgite, 20 parts of 425# portland cement, 15 parts of composite alkali-resistant modified plant fiber, and 35 parts of deionized water are mixed uniformly to form a slurry. The surface of the framework prepared with the heat-insulating water-conveying layer is wetted with water, and the slurry-like mixture is sprayed onto the surface of the heat-insulating water-conveying layer using a paint spraying machine with a spraying thickness of 350 μm. The mixture is solidified at room temperature in an environment of 21°C for 57 h, and deionized water is sprayed twice a day during the solidification process to form a solar interfacial heat-absorbing evaporation layer. Finally, an alkali-resistant solar interfacial evaporation material for aquaculture wastewater treatment is obtained.

[0032] Example 3: A preparation method of an alkali-resistant solar interface evaporation material for aquaculture wastewater treatment, comprising the following preparation steps: preparation of composite alkali-resistant modified plant fiber: 20 parts of jute fiber with a length of 5 mm are placed in 500 parts of a mass fraction of 5% γ-glycidoxypropyltrimethoxysilane ethanol solution, soaked at 60°C for 2h, and then taken out and dried in a 90°C oven for 1.5h; then the dried jute fiber is immersed in a mass fraction of 12% epoxy resin acetone solution, immersed at room temperature for 45min, and then taken out and drained the excess solution on the surface, and then continuously cured at room temperature for 36h in a ventilated environment to obtain alkali-resistant modified jute fiber; finally, 20 parts of alkali-resistant modified jute fiber and 90 parts of bamboo fiber with a length of 2mm are taken and mixed uniformly in a high-speed blender at a speed of 1000rpm for 10min to obtain composite alkali-resistant modified plant fiber.

[0033] S1: 95 parts of yellow clay and 6 parts of 200 mesh reduced iron powder are mixed by weight fraction, 20 parts of deionized water is added, stirred and rolled to a uniform plastic state to form a formable blank, and the blank is pressed and formed and then calcined and modified. During calcination, first heat at a rate of 8°C / min to 400°C for 3h, then heat at a rate of 5°C / min to 900°C for 2h, and finally heat at a rate of 3°C / min to 1100°C for 4h, and then cool the kiln to room temperature to obtain an iron-containing modified clay framework; S2: 65 parts of 200 mesh attapulgite, 20 parts of montmorillonite, 8 parts of composite alkali-resistant modified plant fiber, 15 parts of 425# portland cement and 50 parts of deionized water are mixed uniformly to form a mixture in the form of a slurry, and the mixture is sprayed onto the surface of the iron-containing modified clay framework with a spraying thickness of 1500μm; room temperature setting at 25°C for 72h, with deionized water sprayed twice a day during the period, to form a heat-insulating water-conducting layer; S3: 8 parts of 2000 mesh carbon black, 50 parts of 200 mesh attapulgite, 22 parts of 425# portland cement, 18 parts of composite alkali-resistant modified plant fiber and 40 parts of deionized water are mixed uniformly to form a slurry; the framework prepared with the heat-insulating water-conducting layer is wetted with water, and the slurry-like mixture is sprayed onto the surface of the heat-insulating water-conducting layer with a spraying thickness of 500μm using a paint spraying machine; room temperature setting at 25°C for 68h, with deionized water sprayed twice a day during the period, to form a solar interface heat-absorbing evaporation layer, and finally obtain an alkali-resistant solar interface evaporation material for aquaculture wastewater treatment.

[0034] The following comparative examples 1-4 are compared with example 1.

[0035] Comparative example 1 does not add 200 mesh reduced iron powder, and the remaining steps and parameters are the same as example 1. The final alkali-resistant solar interface evaporation material for aquaculture wastewater treatment is obtained.

[0036] Comparative Example 2: Compared with Example 1, the “alkali-resistant modified jute fiber” was replaced with the same mass of “jute fiber”, and the remaining steps and parameters were the same. The final product was an alkali-resistant solar interfacial evaporation material for aquaculture wastewater treatment.

[0037] Comparative Example 3: Compared with Example 1, the “γ-glycidoxypropyltrimethoxysilane” was replaced with the same mass of “methyltrimethoxysilane”, and the remaining steps and parameters were the same. The final product was an alkali-resistant solar interfacial evaporation material for aquaculture wastewater treatment.

[0038] Comparative Example 4: Compared with Example 1, the “E-51 bisphenol A epoxy resin” was replaced with the same mass of “2123 type ordinary thermosetting phenolic resin”, and the remaining steps and parameters were the same. The final product was an alkali-resistant solar interfacial evaporation material for aquaculture wastewater treatment.

[0039] The alkali-resistant solar interfacial evaporation materials prepared in Examples 1-3 and Comparative Examples 1-4 were subjected to performance testing, and the results are recorded in Table 1.

[0040] 1. Alkali resistance detection: Refer to the modified “GB / T2573-2008 Glass Fiber Reinforced Plastic Water Resistance Test Method”, simulate the weak alkaline environment of aquaculture wastewater (pH=9.0 NaOH solution), completely immerse the sample in the solution, and place it in a constant temperature environment at 25°C for 30 days. During this period, observe the appearance of the sample (coating peeling, skeleton cracking) every 7 days, and after 30 days, measure the mass of the sample using an electronic balance (precision 0.001g), calculate the retention rate using Formula 1, Formula 1: Each group was tested in triplicate and the average value was taken.

[0041] 2. Solar evaporation efficiency detection: Refer to the light-heat material evaporation efficiency test method in CN115975499A, use a xenon light simulator (light intensity 1kW / ㎡, simulate 1 standard sun), fix the sample on a heat-insulating foam support, and only the bottom contacts the simulated aquaculture wastewater (pH=9.0, containing ammonia nitrogen 500mg / L, COD 800mg / L). Record the mass change of the wastewater within 1 hour by electronic balance (precision 0.001g), calculate the evaporation efficiency according to Formula 2, Formula 2: (unit: kg / (m 2 ·h), each group was tested in triplicate and the average value was taken.

[0042] 3. Compressive strength detection: According to the standard GB / T50081-2019 Test Method of Physical and Mechanical Properties of Concrete, the modified clay skeleton containing iron was detected. An electro-hydraulic servo pressure testing machine was used with a loading rate of 2 mm / min. The maximum pressure at the time of skeleton failure was recorded. The compressive strength was calculated according to formula 3, formula 3: (unit: MPa), and the average value of 5 samples in each group was taken.

[0043] 4. Heavy metal adsorption rate detection: Referring to the standard HJ700-2014 Determination of 65 Elements in Water by Inductively Coupled Plasma Mass Spectrometry, the sample was immersed in simulated aquaculture wastewater containing Pb 2+ , Cr 3+ (concentration of 100 mg / L), and oscillated for 24 hours (oscillation rate of 150 r / min) at 25°C. The concentration of heavy metals in the wastewater before and after adsorption was measured by inductively coupled plasma emission spectrometer (ICP-OES). The adsorption rate was calculated according to formula 4, , and the average value of 3 parallel tests in each group was taken.

[0044] Table 1: Performance test results of alkali-resistant solar interfacial evaporation materials for aquaculture wastewater treatment

[0045]

[0046] According to the data in Table 1, the alkali-resistant solar interfacial evaporation materials for aquaculture wastewater treatment of Examples 1-3 have excellent comprehensive performance, showing a gradual improvement in alkali resistance, solar evaporation efficiency, compressive strength and heavy metal adsorption capacity. This is due to the gradient optimization of raw material dosage and precise control of process parameters during preparation, forming a synergistically adapted functional system from the modified clay skeleton containing iron to the layered coating, which can meet the long-term stable operation requirements in weakly alkaline environment of aquaculture wastewater.

[0047] Comparing Example 1 with Comparative Example 1, it can be seen that the addition of iron powder has a key influence on the material performance. The former does not add iron powder in the preparation of clay skeleton, resulting in the lack of stable crystal structure formed by high temperature sintering of the skeleton, which further reduces the overall alkali resistance of the material, and also weakens the mechanical support capacity and the adsorption effect on heavy metals. This fully reflects the important role of iron powder in strengthening the performance of the skeleton and improving the comprehensive adaptability of the material.

[0048] Comparing Example 1 with Comparative Example 2, it can be seen that the alkali-resistant modification process of jute fiber is indispensable. The former directly uses unmodified jute fiber to prepare composite plant fiber without the double modification treatment of epoxy silane and epoxy resin. The fiber is prone to degradation in weakly alkaline environment, which damages the integrity of the coating and further affects the evaporation efficiency and heavy metal adsorption capacity of the material, highlighting the supporting significance of the fiber modification step for long-term performance of the material.

[0049] Comparing Example 1 with Comparative Example 3, it can be seen that the selection of the specific epoxy silane is crucial to the alkali resistance of the material, and the former uses a common silane to replace the γ-glycidyloxypropyltrimethoxysilane, which cannot form a stable cross-linked siloxane protective film on the surface of the jute fibers, and the bonding force between the fibers and the matrix is reduced, the material is prone to changes in coating morphology in a weak alkali environment, resulting in weakening of the overall performance, which proves that the specific epoxy silane is irreplaceable in improving the alkali resistance of the material.

[0050] Comparing Example 1 with Comparative Example 4, it can be seen that the bisphenol A type epoxy resin has a significant impact on the performance of the material, and the former uses a common thermosetting phenolic resin to replace the bisphenol A type epoxy resin, and the common phenolic resin has weak alkali resistance and interfacial bonding force, which cannot effectively improve the alkali resistance of the jute fibers and the adhesion stability of the coating, resulting in a decrease in the structural integrity of the material in a weak alkali environment, and thus the evaporation efficiency, compressive strength and heavy metal adsorption capacity are all weakened, which reflects the key role of the bisphenol A type epoxy resin in realizing the function of the material.

[0051] The above is only an example and description of the concept of the present application, and those skilled in the art can make various modifications or supplements to the described specific embodiments or use similar ways to replace them, as long as they do not deviate from the concept of the present application or exceed the scope defined by the present claims, and they should belong to the protection scope of the present application.

Claims

1. A method for preparing an alkali-resistant solar interfacial evaporative material for aquaculture wastewater treatment, characterized in that, The preparation steps include the following: S1: clay and iron powder are mixed, stirred with water, and rolled to a uniform plastic state to form a formable blank, which is pressed into shape, calcined and modified to obtain an iron-containing modified clay framework; S2: attapulgite, montmorillonite, composite alkali-resistant modified plant fiber, portland cement and water are mixed uniformly into a slurry, and the slurry is sprayed on the surface of the iron-containing modified clay framework, and after solidification at room temperature, a heat-insulating water-conducting layer is formed; S3: carbon black, attapulgite, portland cement, composite alkali-resistant modified plant fiber and water are mixed into a slurry, and the slurry is sprayed on the surface of the heat-insulating water-conducting layer, and after solidification at room temperature, a solar interface heat-absorbing evaporation layer is formed, and finally an alkali-resistant solar interface evaporation material for aquaculture wastewater treatment is obtained; The composite alkali-resistant modified plant fiber is prepared by the following method: jute fibers are placed in an epoxy silane ethanol solution, soaked, taken out, dried, then immersed in an epoxy resin acetone solution, immersed at room temperature, taken out and solidified at room temperature to obtain alkali-resistant modified jute fibers, and the alkali-resistant modified jute fibers are mixed with bamboo fibers to obtain the composite alkali-resistant modified plant fiber; The epoxy silane in the epoxy silane ethanol solution is gamma-glycidoxypropyltrimethoxysilane, and the mass fraction of gamma-glycidoxypropyltrimethoxysilane in the solution is 3%-5%; The epoxy resin in the epoxy resin acetone solution is bisphenol A type epoxy resin, and the mass fraction of bisphenol A type epoxy resin in the solution is 8%-12%, and the solvent is acetone.

2. A method for preparing an alkali-resistant solar interfacial evaporative material for aquaculture wastewater treatment according to claim 1, characterized in that, The raw materials of the composite alkali-resistant modified plant fiber are as follows in terms of weight fraction: 10-20 parts of alkali-resistant modified jute fibers and 80-90 parts of bamboo fibers; wherein the raw materials for preparing the alkali-resistant modified jute fibers are as follows in terms of weight fraction: 10-20 parts of jute fibers, 300-500 parts of epoxy silane ethanol solution and 300-500 parts of epoxy resin acetone solution.

3. A method for preparing an alkali-resistant solar interfacial evaporative material for aquaculture wastewater treatment according to claim 1, characterized in that, The raw materials in S1 are as follows in terms of weight fraction: 90-95 parts of clay, 2-6 parts of iron powder and 15-20 parts of deionized water.

4. A method for preparing an alkali-resistant solar interfacial evaporative material for aquaculture wastewater treatment according to claim 1, characterized in that, In the calcination and modification of S1, the temperature is first increased to 200-400℃ at a rate of 5-8℃ / min, maintained for 2-3h, then increased to 600-900℃ at a rate of 3-5℃ / min, maintained for 1.5-2h, and finally increased to 900-1100℃ at a rate of 2-3℃ / min, maintained for 3-4h, and then cooled to room temperature in the kiln.

5. A method for preparing an alkali-resistant solar interfacial evaporative material for aquaculture wastewater treatment according to claim 1, characterized in that, The raw materials in S2 are as follows in terms of weight fraction: 60-65 parts of attapulgite, 15-20 parts of montmorillonite, 5-8 parts of composite alkali-resistant modified plant fiber, 10-15 parts of portland cement and 40-50 parts of deionized water; the spraying thickness is 1000-1500μm, the solidification temperature at room temperature is 18-25℃, and the solidification time is 52-72h, during which deionized water is sprayed 1-2 times a day.

6. A method for preparing an alkali-resistant solar interfacial evaporative material for aquaculture wastewater treatment according to claim 1, characterized in that, The raw materials in the S3 are as follows in parts by weight: carbon black 5-8 parts, attapulgite 45-50 parts, silicate cement 18-22 parts, composite alkali-resistant modified plant fiber 12-18 parts, and deionized water 30-40 parts; the spraying thickness is 200-500 μm, the room temperature solidification temperature is 18-25℃, and the solidification time is 46-68 h, during which deionized water is sprayed 1-2 times a day.

7. The alkali-resistant solar energy interfacial evaporation material for aquaculture wastewater treatment is prepared by the method according to any one of claims 1-6.

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