Preparation method and application of composite modified asphalt based on epoxy modified retired fan blade

Abstract

The invention discloses a preparation method and application of composite modified asphalt based on an epoxy modified retired fan blade. The method comprises the following steps: mechanically crushing and screening the retired fan blade; the screened out-of-service fan blade powder is put into an ultrasonic cleaner, and a deionized water solution is added for cleaning; the retired fan blade powder and the epoxy modifier are mixed and stirred uniformly; heating and reacting the uniformly stirred mixture to obtain an epoxy composite asphalt modifier; the preparation method comprises the following steps: heating matrix asphalt to a molten state, then adding an SBS modifier, and carrying out high-speed shear stirring and development to obtain SBS modified asphalt; and adding an epoxy composite asphalt modifier into the obtained SBS modified asphalt, carrying out high-speed shear stirring and development, and then carrying out heat preservation to obtain the retired fan blade composite modified asphalt. The composite modified asphalt obtained by the invention has good aging resistance, crack resistance, low temperature resistance, durability and the like, and the overall uniformity and stability of the modified asphalt are improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of solid waste resource utilization, and more specifically, relates to a preparation method and application of epoxy-modified retired wind turbine blades composite modified asphalt. Background Art

[0002] Since 2004, China's wind power industry has shown explosive growth; according to market statistics, as of the end of 2023, the total installed capacity of wind power in the country reached 430 million kilowatts, and the number of wind turbines reached approximately 1.95 million; however, with the rapid development of the wind power industry, the wind turbines have reached the peak of retirement, and it is estimated that from 2025 to 2030, the amount of retired wind turbine blades will reach 440,000 - 660,000 tons. How to realize the resource utilization of retired blades at the lowest cost is an important task.

[0003] In highway engineering construction, asphalt modifiers are usually used to improve the road performance of roads. However, traditional asphalt modifiers usually use high molecular polymers, petroleum-based chemical additives, etc., which have problems such as high price, easy aging during long-term use, and reduced modification effect; at the same time, high molecular polymer modifiers may produce volatile organic compounds (VOCs) during use, causing negative impacts on the environment. Since the materials of retired wind turbine blades are mainly composite materials composed of glass fiber, thermosetting resin, carbon fiber, etc., they have the characteristics of light weight, high temperature resistance, corrosion resistance, and high strength, which highly coincide with the demand for high-quality modifiers in highway engineering construction; through the epoxidation modification process, the glass fiber and resin materials in the waste wind turbine blades are transformed into composite fiber asphalt modifiers with high added value, improving the surface adhesion of the retired wind turbine blade asphalt modifier and enhancing the anti-aging, anti-cracking, and low-temperature resistance of the modified asphalt, etc., meeting the requirements of highway engineering construction for high-performance asphalt materials. At the same time, it solves the severe problem of the wave of retired wind turbine blades and realizes the resource utilization of waste wind turbine blades. Summary of the Invention

[0004] Aiming at the above defects or improvement requirements of the prior art, the present invention provides a preparation method and application of epoxy-modified retired wind turbine blades composite modified asphalt. By epoxidizing the glass fiber and resin materials in the retired wind turbine blades, surface active groups are given to them, effectively enhancing the adhesion between the epoxy composite asphalt modifier and the modified asphalt, improving the overall uniformity and stability of the modified asphalt, thereby significantly improving the strength and anti-shear performance of the asphalt pavement. At the same time, it solves the severe problem of the wave of retired wind turbine blades, converts the composite materials in the retired wind turbine blades into asphalt modifiers, and thus realizes the efficient conversion and maximization utilization of waste resources.

[0005] To achieve the above object, according to one aspect of the present invention, a preparation method of composite modified asphalt based on epoxy modified retired wind turbine blades is provided, including the following steps:

[0006] S100: Mechanically crush the retired wind turbine blades and screen the powder of the retired wind turbine blades with appropriate size;

[0007] S200: Put the screened powder of the retired wind turbine blades into an ultrasonic cleaner and add deionized water solution to obtain the washed powder of the retired wind turbine blades;

[0008] S300: Mix the obtained washed powder of the retired wind turbine blades with an epoxy modifier in a certain proportion and stir evenly at room temperature;

[0009] S400: Heat the evenly stirred mixture to 60 - 80 °C and react for 8 - 12 h to fully combine the epoxy modifier with the surface active groups of the fiber material of the retired wind turbine blade powder to obtain an epoxy composite asphalt modifier;

[0010] S500: Heat the 90# base asphalt to a molten state, add an SBS modifier, and perform high - speed shear stirring and development to obtain SBS modified asphalt;

[0011] S600: Heat the obtained SBS modified asphalt to a molten state, add the epoxy composite asphalt modifier, and perform high - speed shear stirring and development, and then keep it warm to obtain the composite modified asphalt of the retired wind turbine blade.

[0012] Further, the particle size of the powder of the retired wind turbine blades after crushing is 0 - 0.3 mm, and the content ratio of glass fiber is ≥70%.

[0013] Further, the epoxy modifier is a mixture of epichlorohydrin, bisphenol A type epoxy resin, γ - glycidoxypropyltriethoxysilane, ethylene oxide or nano - silica.

[0014] Further, in step S200, the temperature of the ultrasonic cleaner is set between 40 - 60 °C, the frequency is 40 - 60 kHz, and the cleaning time is 20 - 30 min.

[0015] Further, in step S300, the dosage of the epoxy modifier is 10 - 30 parts, and the dosage of the powder of the retired wind turbine blades is 70 - 90 parts.

[0016] Further, in step S500, it specifically includes the following steps:

[0017] S510: Heat the 90# base asphalt to 140 - 160 °C until it is in a molten state, and then add the SBS modifier;

[0018] S520: High-speed shear stirring is carried out on the 90# base asphalt added with SBS modifier, the stirring speed is 3000 r / min to 5000 r / min, and the shearing time is 30 min to 60 min;

[0019] S530: Heat the mixture after high-speed shear stirring to 140 - 160 °C and develop it at a stirring speed of 300 r / min to 500 r / min for 1 h to 2 h to obtain SBS modified asphalt.

[0020] Furthermore, in step S510, the dosage of 90# base asphalt is 94 - 97 parts, and the dosage of SBS modifier is 3 - 6 parts.

[0021] Furthermore, in the said step S600, it specifically includes the following steps:

[0022] S610: Heat the SBS modified asphalt to 140 - 160 °C until it is in a molten state, and then add the epoxy modified composite fiber asphalt modifier;

[0023] S620: Carry out high-speed shear stirring on the SBS modified asphalt added with the epoxy modified composite fiber asphalt modifier, the stirring speed is 4000 r / min to 5000 r / min, and the shearing time is 40 min to 60 min,

[0024] S630: Heat the mixture after high-speed shear stirring to 140 - 160 °C and develop it at a stirring speed of 400 r / min to 500 r / min for 20 - 40 min;

[0025] S640: Keep the developed mixture in an oven at 150 - 170 °C for 20 - 30 min to obtain the composite fiber modified asphalt for retired wind turbine blades.

[0026] Furthermore, in the said step S610, the dosage of the epoxy modified composite fiber asphalt modifier is 3 - 8 parts, and the dosage of SBS modified asphalt is 92 - 97 parts.

[0027] According to the second aspect of the present invention, there is provided an application of the epoxy modified retired wind turbine blade composite modified asphalt in road engineering asphalt concrete.

[0028] Generally speaking, compared with the prior art through the above technical solutions conceived by the present invention, the following beneficial effects can be achieved:

[0029] 1. The preparation method of the composite modified asphalt of the present invention epoxidizes and modifies the glass fiber and resin materials in the retired wind turbine blades, endows them with surface active groups, effectively enhances the adhesion between the epoxy composite asphalt modifier and the modified asphalt, improves the overall uniformity and stability of the modified asphalt, and thus significantly improves the strength and shear resistance of the asphalt pavement.

[0030] 2. The preparation method of the composite modified asphalt of the present invention introduces an epoxy modifier, which reacts chemically with the hydroxyl, carboxyl or amino groups on the material surface, and effectively enhances the bonding performance between the modifier and the asphalt matrix by forming strong chemical bonds; at the same time, the reactivity of the epoxy modifier can endow the fiber materials of retired wind turbine blades with excellent interfacial properties, making them exhibit more stable performance under complex road use conditions such as high temperature and high pressure.

[0031] 3. The preparation method of the composite modified asphalt of the present invention prepares a composite modified asphalt with good anti-aging, anti-cracking, low-temperature resistance and durability, etc., which meets the requirements of highway engineering construction for high-performance asphalt materials. At the same time, it solves the severe problem of the wave of retired wind turbine blades, converts the composite materials in the retired wind turbine blades into asphalt modifiers, and thus realizes the efficient conversion and maximization utilization of waste resources.

[0032] 4. The preparation method of the composite modified asphalt of the present invention realizes the successful preparation of high-performance composite modified asphalt through a simple process flow and low-cost investment. It not only simplifies the complex processes of traditional asphalt modification, greatly reduces the production cost, reduces the emission of harmful substances and energy consumption, reflects the concept of green and sustainable development, and meets the requirements of modern society for the high-efficiency, environmental protection and sustainable development of building materials.

[0033] 5. The preparation method of the composite modified asphalt of the present invention prepares a composite modified asphalt with excellent anti-aging performance and durability, which can resist the long-term erosion of ultraviolet rays, oxidation and high-temperature environment. When applied to road engineering, it can extend the overall service life of the road surface, reduce the maintenance frequency, and reduce the maintenance cost, and has significant economic and social benefits. Description of the Drawings

[0034] Figure 1 It is a schematic flow chart of a method for preparing composite modified asphalt based on epoxy-modified retired wind turbine blades according to an embodiment of the present invention;

[0035] Figure 2 It is an electron micrograph of the composite modified asphalt prepared in Example 1 of the present invention. Detailed Embodiments

[0036] In order to make the objectives, technical solutions and advantages of the present invention more clear and understandable, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0037] In this patent, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, such that a process, method, article or device comprising a series of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "comprising..." does not exclude the presence of additional identical elements in the process, method, article or device comprising the element.

[0038] As Figure 1 shown, an embodiment of the present invention provides a preparation method of composite modified asphalt based on epoxy modified retired wind turbine blades, comprising the following steps:

[0039] S100: Mechanically crush the retired wind turbine blades and screen the retired wind turbine blade powder of appropriate size;

[0040] Further, the retired wind turbine blades are mainly composed of a composite material such as glass fiber, thermosetting resin and carbon fiber. After mechanical crushing, the particle size of the screened retired wind turbine blade powder is 0 - 0.3 mm, and the content ratio of glass fiber is ≥ 70%.

[0041] S200: Put the screened retired wind turbine blade powder into an ultrasonic cleaner and add deionized aqueous solution to obtain the cleaned retired wind turbine blade powder;

[0042] Further, the temperature of the ultrasonic cleaner needs to be set between 40 - 60 °C, and the retired wind turbine blade powder is cleaned at a frequency of 40 - 60 kHz, and the cleaning time is 20 - 30 min.

[0043] The cavitation effect generated by the high-frequency vibration of the ultrasonic cleaner can effectively remove impurities such as dust, oil stains and residual glue on the surface of the retired wind turbine blade powder. Deionized water as the cleaning medium can further enhance the cleaning effect, ensure the purity of the powder, and enhance the adhesion between the retired wind turbine blade powder and the epoxy modifier.

[0044] S300: Mix the obtained cleaned retired wind turbine blade powder with the epoxy modifier in a certain proportion and stir evenly at room temperature;

[0045] Further, the epoxy modifier is a mixture of epichlorohydrin, bisphenol A epoxy resin, γ-glycidoxypropyltriethoxysilane, ethylene oxide, or nano-silica.

[0046] The dosage of the epoxy modifier is 10 - 30 parts, and the dosage of the retired wind turbine blade powder is 70 - 90 parts.

[0047] S400: Heat the uniformly stirred mixture to 60 - 80 °C and react for 8 - 12 h to fully combine the active groups on the surface of the fiber material of the epoxy modifier and the retired wind turbine blade powder, obtaining an epoxy composite asphalt modifier;

[0048] Through heating and reaction, the epoxy modifier can chemically bond with the active groups on the surface of the fiber material in the retired wind turbine blade powder, improving the interfacial compatibility between the fiber and the epoxy resin, thereby enhancing the overall performance of the composite material.

[0049] S500: Heat the 90# base asphalt to the molten state, add the SBS modifier, and perform high-speed shear stirring and development to obtain SBS modified asphalt;

[0050] S510: Heat the 90# base asphalt to 140 - 160 °C until it reaches the molten state, and then add the SBS modifier;

[0051] Further, the dosage of the 90# base asphalt is 94 - 97 parts, and the dosage of the SBS modifier is 3 - 6 parts.

[0052] S520: Perform high-speed shear stirring on the 90# base asphalt with the SBS modifier added, with a stirring speed of 3000 r / min - 5000 r / min and a shear time of 30 min - 60 min;

[0053] S530: Heat the mixture after high-speed shear stirring to 140 - 160 °C and develop it at a stirring speed of 300 r / min - 500 r / min for 1 h - 2 h to obtain SBS modified asphalt.

[0054] S600: Heat the obtained SBS modified asphalt to the molten state, add the epoxy composite asphalt modifier, and perform high-speed shear stirring and development, and then keep it warm to obtain the retired wind turbine blade composite modified asphalt.

[0055] S610: Heat the SBS modified asphalt to 140 - 160 °C until it reaches the molten state, and then add the epoxy composite asphalt modifier;

[0056] Further, the dosage of the epoxy composite asphalt modifier is 3 - 8 parts, and the dosage of the SBS modified asphalt is 92 - 97 parts.

[0057] Furthermore, the epoxy composite asphalt modifier can be added once or multiple times.

[0058] S620: High-speed shear stirring is performed on the SBS modified asphalt added with the epoxy composite asphalt modifier, with a stirring speed of 4000 r / min to 5000 r / min and a shearing time of 40 min to 60 min;

[0059] S630: The mixture after high-speed shear stirring is heated to 140 - 160 °C and developed for 20 - 40 min at a stirring speed of 400 r / min to 500 r / min;

[0060] S640: The developed mixture is kept warm in an oven at 150 - 170 °C for 20 - 30 min to obtain the composite modified asphalt for retired wind turbine blades.

[0061] The composite modified asphalt prepared by the present invention, through the epoxy modification of the glass fiber and resin materials in the retired wind turbine blades, endows them with surface active groups, effectively enhancing the adhesion between the epoxy modified composite fiber asphalt modifier and the modified asphalt, improving the overall uniformity and stability of the modified asphalt. The prepared composite modified asphalt has good properties such as anti-aging, crack resistance, low-temperature resistance, and durability, meeting the requirements of highway engineering construction for high-performance asphalt materials. At the same time, it solves the severe problem of the wave of retired wind turbine blades, converting the composite materials in the retired wind turbine blades into epoxy composite asphalt modifiers, thus realizing the efficient conversion and maximized utilization of waste resources.

[0062] Furthermore, an application of the epoxy modified retired wind turbine blade composite modified asphalt in asphalt concrete for road engineering is provided.

[0063] The composite modified asphalt of the present invention can be used for road construction of high-grade highways, urban expressways, and heavy traffic sections.

[0064] Example 1

[0065] As Figure 1 shown, the composite modified asphalt is prepared by a preparation method of epoxy modified retired wind turbine blade composite modified asphalt according to an embodiment of the present invention, including the following steps:

[0066] S100: The retired wind turbine blades are mechanically crushed, and the retired wind turbine blade powder with a particle size of 0 - 0.3 mm is screened, with the glass fiber content accounting for 75%;

[0067] S200: The screened retired wind turbine blade powder is put into an ultrasonic cleaner, and deionized aqueous solution is added. The temperature of the ultrasonic cleaner is 50 °C, the frequency is 40 kHz, and it is cleaned for 25 min to obtain the cleaned retired wind turbine blade powder;

[0068] S300: Take 80 parts of the powder of the retired wind turbine blade after cleaning and 20 parts of epichlorohydrin, mix them, and stir evenly at room temperature;

[0069] S400: Heat the evenly stirred mixture to 70 °C and react for 10 h to obtain an epoxy composite asphalt modifier;

[0070] S500: Heat 90# base asphalt to a molten state, add SBS modifier, and carry out high-speed shearing stirring and development to obtain SBS modified asphalt;

[0071] S510: Heat 94 parts of 90# base asphalt to 150 °C until it is in a molten state, and then add 6 parts of SBS modifier;

[0072] S520: Carry out high-speed shearing stirring on the 90# base asphalt added with SBS modifier, with a stirring speed of 4000 r / min and a shearing time of 40 min;

[0073] S530: Heat the mixture after high-speed shearing stirring to 150 °C and develop it at a stirring speed of 400 r / min for 1.5 h to obtain SBS modified asphalt.

[0074] S600: Heat the obtained SBS modified asphalt to a molten state, add the epoxy composite asphalt modifier, and carry out high-speed shearing stirring and development, and then keep it warm to obtain the composite modified asphalt of the retired wind turbine blade.

[0075] S610: Heat 95 parts of SBS modified asphalt to 160 °C until it is in a molten state, and then add 5 parts of the epoxy composite asphalt modifier;

[0076] S620: Carry out high-speed shearing stirring on the SBS modified asphalt added with the epoxy composite asphalt modifier, with a stirring speed of 4500 r / min and a shearing time of 60 min,

[0077] S630: Heat the mixture after high-speed shearing stirring to 160 °C and develop it at a stirring speed of 400 r / min for 30 min;

[0078] S640: Keep the developed mixture warm in an oven at 160 °C for 25 min to obtain the composite modified asphalt of the retired wind turbine blade.

[0079] Performance test of the composite modified asphalt of the retired wind turbine blade: Test the penetration, softening point, ductility, rutting factor, low-temperature stiffness modulus, adhesion and other properties of the composite modified asphalt of the retired wind turbine blade prepared above according to the test method of asphalt. The performance test results are shown in Table 1.

[0080] Example 2

[0081] In this embodiment, other contents are the same as those in Embodiment 1. The difference from Embodiment 1 is only that in step 300, the epoxy modifier is bisphenol A epoxy resin. 80 parts of the cleaned retired wind turbine blade powder and 20 parts of bisphenol A epoxy resin are taken and mixed evenly by stirring at room temperature.

[0082] Performance test of the composite modified asphalt of retired wind turbine blades: According to the test method of asphalt, the penetration, softening point, ductility, rutting factor, low temperature stiffness modulus, adhesion and other performances of the above-prepared composite modified asphalt of retired wind turbine blades are tested. The performance test results are shown in Table 1.

[0083] Embodiment 3

[0084] In this embodiment, other contents are the same as those in Embodiment 1. The difference from Embodiment 1 is only that in step 300, the epoxy modifier is γ-glycidoxypropyltriethoxysilane. 80 parts of the cleaned retired wind turbine blade powder and 20 parts of γ-glycidoxypropyltriethoxysilane are taken and mixed evenly by stirring at room temperature.

[0085] Performance test of the composite modified asphalt of retired wind turbine blades: According to the test method of asphalt, the penetration, softening point, ductility, rutting factor, low temperature stiffness modulus, adhesion and other performances of the above-prepared composite modified asphalt of retired wind turbine blades are tested. The performance test results are shown in Table 1.

[0086] Embodiment 4

[0087] In this embodiment, other contents are the same as those in Embodiment 1. The difference from Embodiment 1 is only that in step 300, the epoxy modifier is ethylene oxide. 80 parts of the cleaned retired wind turbine blade powder and 20 parts of ethylene oxide are taken and mixed evenly by stirring at room temperature.

[0088] Performance test of the composite modified asphalt of retired wind turbine blades: According to the test method of asphalt, the penetration, softening point, ductility, rutting factor, low temperature stiffness modulus, adhesion and other performances of the above-prepared composite modified asphalt of retired wind turbine blades are tested. The performance test results are shown in Table 1.

[0089] Embodiment 5

[0090] In this embodiment, other contents are the same as those in Embodiment 1. The difference from Embodiment 1 is only that in step 300, the epoxy modifier is modified nano-silica. 80 parts of the cleaned retired wind turbine blade powder and 20 parts of modified nano-silica are taken and mixed evenly by stirring at room temperature.

[0091] Performance Test of Composite Modified Asphalt from Retired Wind Turbine Blades: Test the penetration, softening point, ductility, rutting factor, low-temperature stiffness modulus, adhesion and other properties of the above-prepared composite modified asphalt from retired wind turbine blades according to the asphalt test method. The performance test results are shown in Table 1.

[0092] Example 6

[0093] In this example, other contents are the same as those in Example 1. The difference from Example 1 is only that in step 610, 97 parts of SBS modified asphalt are heated to 160 °C until it is in a molten state, and then 3 parts of epoxy composite asphalt modifier are added.

[0094] Performance Test of Composite Modified Asphalt from Retired Wind Turbine Blades: Test the penetration, softening point, ductility, rutting factor, low-temperature stiffness modulus, adhesion and other properties of the above-prepared composite modified asphalt from retired wind turbine blades according to the asphalt test method. The performance test results are shown in Table 1.

[0095] Comparative Example 1

[0096] In this example, other contents are the same as those in Example 1. The difference from Example 1 is only that the SBS modified asphalt prepared through step S500 is not modified by adding an epoxy composite asphalt modifier.

[0097] Performance Test of SBS Modified Asphalt: Test the penetration, softening point, ductility, rutting factor, low-temperature stiffness modulus, adhesion and other properties of the above-prepared SBS modified asphalt according to the asphalt test method. The performance test results are shown in Table 1.

[0098] Comparative Example 2

[0099] In this example, SBS modified asphalt is prepared through step S500 and is not modified by adding an epoxy-modified composite fiber asphalt modifier.

[0100] Preparation Method of SBS Modified Asphalt:

[0101] S510: Heat 100 parts of 90# base asphalt to 150 °C until it is in a molten state, and then add 5 parts of YH791 SBS modifier;

[0102] S520: Conduct high-speed shear stirring on the 90# base asphalt with YH791 SBS modifier. The stirring speed is 4000 r / min, and the shearing time is 40 min;

[0103] S530: Heat the mixture after high-speed shear stirring to 150 °C and develop it at a stirring speed of 400 r / min for 1.5 h to obtain SBS modified asphalt.

[0104] Performance testing of SBS modified asphalt: Test the penetration, softening point, ductility, rutting factor, low-temperature stiffness modulus, adhesion and other properties of the above-prepared SBS modified asphalt according to the asphalt testing method. The performance test results are shown in Table 1.

[0105] Comparative Example 3

[0106] In this embodiment, rubber composite modified asphalt is prepared through step S500, and no epoxy modified composite fiber asphalt modifier is added for modification.

[0107] Preparation method of rubber composite modified asphalt:

[0108] S510: Heat 100 parts of 90# base asphalt to 165 °C until it is in a molten state, then add 2.5 parts of YH791 SBS modifier, 16 parts of rubber powder and a compatibilizer, slowly raise the temperature to 185 °C, and stir at a low speed for 40 min for swelling, then perform high-speed shearing at a speed of 5000 r / min for 60 min, add a stabilizer to the mixture after high-speed shearing and stir at a high speed for 2 h to obtain rubber composite modified asphalt.

[0109] Performance testing of rubber composite modified asphalt: Test the penetration, softening point, ductility, rutting factor, low-temperature stiffness modulus, adhesion and other properties of the above-prepared rubber composite modified asphalt according to the asphalt testing method. The performance test results are shown in Table 1.

[0110] Performance evaluation

[0111] Table 1 Test results of asphalt performance of Examples 1-6 and Comparative Examples 1-3

[0112]

[0113] As can be seen from Examples 1-6, the penetration of the composite modified asphalt prepared by using the epoxy composite asphalt modifier made from retired wind turbine blades after epoxy modification is between 55 and 65 (0.01 mm), the softening point > 75 °C, the ductility at 5 °C > 20 cm, the rutting factor > 10 G / sinδ, and the stiffness modulus S(-12 °C) < 140 MPa. Its various properties are very good, which can meet the various indicators of asphalt. Based on its production formula and process, it is suitable for solving the severe problem of the wave of retired wind turbine blades, converting the composite materials in retired wind turbine blades into composite asphalt modifiers, thereby realizing the efficient conversion and maximization utilization of waste resources. The penetration of the composite modified asphalt prepared by Example 1 is not much different from that of the composite modified asphalt prepared by Examples 2-6. The softening point, ductility, rutting factor, stiffness modulus S(-12 °C), and adhesion of the composite modified asphalt prepared by Example 1 are better than those of Examples 2-6, indicating that the epoxy composite asphalt modifier prepared by using epichlorohydrin as the epoxy modifier has a better effect.

[0114] As Figure 2 described, according to the electron microscope scanning images, after the epoxy modification of the modified asphalt, precipitates appeared on the surface of the retired wind turbine blade powder, resulting in a blurred surface. This indicates that the epoxy modification treatment can improve the compatibility between the retired wind turbine blade powder and the asphalt, and thus enhance its adhesion performance with the asphalt.

[0115] It can be seen from Examples 1 to 6 and Comparative Example 1 that the softening point, ductility, rutting factor and adhesion grade of the composite modified asphalt prepared from Examples 1 to 6 are significantly greater than those of Comparative Example 1, and the stiffness modulus S(-12°C) is significantly less than that of Comparative Example 1. Therefore, it can be shown that compared with the asphalt prepared without adding the epoxy composite asphalt modifier, the composite modified asphalt prepared with the epoxy composite asphalt modifier made from the retired wind turbine blades after epoxy modification effectively improves the bonding performance between the material and the asphalt matrix, and enhances its low-temperature toughness, crack resistance and anti-aging performance.

[0116] It can be seen from Example 1 and Comparative Example 2 that compared with Example 1, the softening point of the SBS modified asphalt prepared from Comparative Example 2 decreased by 9.5%, and the rutting factor decreased most significantly, less than 1 / 2 of the composite modified asphalt prepared from Example 1. The increase in the stiffness modulus S(-12°C) was also relatively obvious. Therefore, it can be shown that compared with the SBS modified asphalt, the composite modified asphalt prepared with the epoxy composite asphalt modifier made from the retired wind turbine blades after epoxy modification has improved high-temperature performance and low-temperature crack resistance.

[0117] It can be seen from Example 1 and Comparative Example 3 that compared with Example 1, the penetration of the rubber composite modified asphalt prepared from Comparative Example 3 decreased slightly, the softening point decreased by 6.7%, the ductility decreased most significantly, only 36.4% of that of Example 1, the rutting factor decreased, and the increase in the stiffness modulus S(-12°C) was also relatively obvious. Therefore, it can be shown that compared with the rubber composite modified asphalt, the composite modified asphalt prepared with the epoxy composite asphalt modifier made from the retired wind turbine blades after epoxy modification has improved high-temperature performance and low-temperature crack resistance.

[0118] Those skilled in the art can easily understand that the above are only the preferred embodiments of the present invention and are not used to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for preparing composite modified asphalt based on epoxy-modified retired wind turbine blades, characterized in that: The following steps are involved: S100: Mechanically crushing the retired fan blades to screen retired fan blade powder of appropriate size; S200: placing the screened retired fan blade powder into an ultrasonic cleaner, and adding a deionized water solution to obtain cleaned retired fan blade powder; S300: mixing the cleaned retired fan blade powder and the epoxy modifier in a certain proportion, and stirring evenly at room temperature; S400: heating the stirred mixture to 60-80° C. and reacting for 8-12 hours to fully combine the epoxy modifier with the surface active groups of the fiber material of the retired wind turbine blade powder to obtain an epoxy composite asphalt modifier; S500: 90# base asphalt is heated to a molten state, SBS modifier is added, and high-speed shear stirring and development are performed to obtain SBS modified asphalt; S600: The obtained SBS modified asphalt is heated to a molten state, an epoxy composite asphalt modifier is added, and high-speed shear stirring and development are performed, and then the heat is kept to obtain a composite modified asphalt for retired wind turbine blades.

2. The method for preparing composite modified asphalt based on epoxy-modified retired wind turbine blades according to claim 1 is characterized in that: The particle size of the crushed retired fan blade powder is 0-0.3 mm, and the content of glass fiber accounts for ≥70%.

3. The method for preparing composite modified asphalt based on epoxy-modified retired wind turbine blades according to claim 1 is characterized in that: The epoxy modifier is a mixture of epichlorohydrin, bisphenol A epoxy resin, γ-glycidyloxypropyltriethoxysilane, ethylene oxide or nano silicon dioxide.

4. A method for preparing composite modified asphalt based on epoxy-modified retired wind turbine blades according to any one of claims 1 to 3, characterized in that: In step S200, the temperature of the ultrasonic cleaner is set between 40 and 60°C, the frequency is set between 40 and 60 kHz, and the cleaning time is set between 20 and 30 minutes.

5. A method for preparing composite modified asphalt based on epoxy-modified retired wind turbine blades according to any one of claims 1 to 3, characterized in that: In step S300, the epoxy modifier is added in an amount of 10 to 30 parts, and the retired wind turbine blade powder is added in an amount of 70 to 90 parts.

6. A method for preparing composite modified asphalt based on epoxy-modified retired wind turbine blades according to any one of claims 1 to 3, characterized in that: The step S500 specifically includes the following steps: S510: Heat 90# base asphalt to 140-160°C until it is molten, and then add SBS modifier; S520: subjecting the 90# base asphalt to which the SBS modifier is added to the asphalt to high-speed shear stirring, the stirring speed is 3000r / min to 5000r / min, and the shear time is 30min to 60min; S530: The mixture after high-speed shear stirring is heated to 140-160°C, and developed at a stirring speed of 300r / min-500r / min for 1h-2h to obtain SBS modified asphalt.

7. The method for preparing composite modified asphalt based on epoxy-modified retired wind turbine blades according to claim 6 is characterized in that: In step S510, the amount of 90# base asphalt is 94 to 97 parts, and the amount of SBS modifier is 3 to 6 parts.

8. A method for preparing composite modified asphalt based on epoxy-modified retired wind turbine blades according to any one of claims 1 to 3, characterized in that: The step S600 specifically includes the following steps: S610: heating the SBS modified asphalt to 140-160°C until it is molten, and then adding the epoxy composite asphalt modifier; S620: subjecting the SBS modified asphalt to which the epoxy composite asphalt modifier is added to high-speed shear stirring, the stirring speed is 4000r / min to 5000r / min, and the shear time is 40min to 60min; S630: heating the mixture after high-speed shear stirring to 140-160° C., and stirring at a stirring speed of 400 r / min-500 r / min for 20-40 min; S640: Keep the grown mixture in an oven at 150-170°C for 20-30 minutes.

9. The method for preparing composite modified asphalt based on epoxy-modified retired wind turbine blades according to claim 8, characterized in that: In the step S610, the epoxy composite asphalt modifier is added in an amount of 3 to 8 parts, and the SBS modified asphalt is added in an amount of 92 to 97 parts.

10. Application of the composite modified asphalt based on epoxy-modified retired wind turbine blades according to any one of claims 1 to 9 in asphalt concrete for road engineering.

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