Water damage resistant asphalt modifier, preparation method therefor and use thereof

Abstract

The present invention relates to the technical field of road building materials. Disclosed are a water damage resistant asphalt modifier, a preparation method therefor and a use thereof. The method for preparing the water damage resistant asphalt modifier comprises the following steps: S1: performing pulverization treatment on a decommissioned wind power blade and then performing sieving to obtain decommissioned wind power blade powder; S2, mixing the decommissioned wind power blade powder in step S1 with a silane coupling agent hydrolysis solution, and then drying to obtain siliconized decommissioned wind power blade powder; and S3, mixing the siliconized decommissioned wind power blade powder in step S2 with an elastomer, and then performing melt blending, crushing and sieving to obtain the water damage resistant asphalt modifier. The water damage resistant asphalt modifier is used for preparing modified asphalt and a modified asphalt mixture, and the working performance and the road performance of the modified asphalt and the modified asphalt mixture are significantly improved.

Description

A water-damage-resistant asphalt modifier and its preparation method and application

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of Chinese patent application No. 202311088004.5 filed on August 28, 2023, the contents of which are incorporated herein by reference. Technical Field

[0003] The present invention relates to the technical field of road construction materials, and in particular to an anti-water damage asphalt modifier, a preparation method and application thereof. Background Art

[0004] FRP is a thermosetting composite material with glass fiber as the reinforcing material and epoxy resin, unsaturated polyester resin and polyurethane resin as the matrix resin. Waste FRP refers to the waste scraps, substandard products and composite materials that cannot meet the working performance requirements and need to be disposed of during the production, transportation, sales and use of FRP-related industries and enterprises. Traditional methods of treating waste FRP include landfill and burning. However, these methods do not fully utilize the mechanical properties and residual value of waste FRP. They also require a large amount of land resources and cause serious pollution to groundwater and air. Retired wind turbine blades contain a large amount of glass fiber. Faced with a large number of retired wind turbine blades in the future, how to reuse them as resources and high value has become a difficult problem that the industry generally pays attention to. Therefore, it is of great significance to develop a low-cost and high-efficiency method for regenerating retired wind turbine blades and making them into high-value-added products that meet performance requirements.

[0005] To improve the quality and extend the life of asphalt pavements, the use of SBS-modified asphalt for pavement construction was proposed internationally in the 1990s. SBS is a thermoplastic copolymer with a triblock structure formed by the polymerization of butadiene and styrene, and is available in both linear and star-shaped structures. At room temperature, the polystyrene hard segments (PS segments) in the SBS macromolecular structure aggregate to form physical crosslinks due to their high cohesive energy, giving SBS its rubbery elasticity. Based on the unique structural characteristics and performance advantages of SBS, its use in asphalt modification can significantly improve the asphalt's low-temperature cracking resistance and high-temperature rutting resistance. Therefore, SBS-modified asphalt has been widely used in the construction of high-speed highways.

[0006] Due to the high price of SBS, the cost of road construction remains high. In recent years, research has been carried out on how to use low-cost, high-quality new materials to replace the higher-cost SBS while ensuring that the durability of asphalt pavement is not affected. However, an ideal modified asphalt material has not yet appeared.

[0007] Summary of the Invention

[0008] The purpose of the present invention is to overcome the problems of difficulty in disposing of retired wind turbine blades and high price of SBS modified asphalt in the prior art, and to provide a water-damage-resistant asphalt modifier and its preparation method and application. The water-damage-resistant asphalt modifier has the characteristics of excellent performance and low price, and its preparation method is simple.

[0009] In order to achieve the above object, the present invention provides a method for preparing a water damage resistant asphalt modifier, which comprises the following steps:

[0010] S1: Powdering and sieving retired wind turbine blades to obtain retired wind turbine blade powder;

[0011] S2: mixing the retired wind turbine blade powder in step S1 with a silane coupling agent hydrolyzed solution, and then drying to obtain silicified retired wind turbine blade powder;

[0012] S3: The siliconized retired wind turbine blade powder in step S2 is mixed with an elastomer, and then melt-blended, crushed and sieved to obtain a water-damage resistant asphalt modifier.

[0013] Preferably, in step S1, the content of glass fiber in the retired wind turbine blade is greater than 70% by weight.

[0014] Preferably, in step S1, the particle size of the retired wind turbine blade powder is ≤0.3 mm.

[0015] Preferably, in step S2, the silane coupling agent hydrolysis solution is obtained by mixing the silane coupling agent, water and anhydrous ethanol, wherein the weight ratio of the silane coupling agent, water and anhydrous ethanol is 14-19:6-11:100.

[0016] Preferably, the weight ratio of the retired wind turbine blade powder to the silane coupling agent is 100:10-20.

[0017] Preferably, in step S2, the mixing conditions include: temperature of 55-85° C. and time of 10-60 min.

[0018] Preferably, in step S3, the weight ratio of the siliconized retired wind turbine blade powder to the elastomer is 100:15-45.

[0019] Preferably, the elastomer is selected from SBR, SBS, SIS, SEBS, IIR or EVA.

[0020] Preferably, in step S3, the melt blending conditions include: temperature of 50-70° C., rotation speed of 40-70 rpm, and time of 15-40 min.

[0021] Preferably, the crushing is freeze-crushing.

[0022] Preferably, in step S3, the particle size of the water-damage resistant asphalt modifier is ≤0.3 mm.

[0023] The second aspect of the present invention provides a water damage resistant asphalt modifier prepared by the above method.

[0024] The third aspect of the present invention provides a modified asphalt, which comprises a base asphalt and a modifier, wherein the modifier is the water damage resistant asphalt modifier described above and optionally SBS.

[0025] Preferably, the weight ratio of the modifier to the base asphalt is 1-20:100.

[0026] A fourth aspect of the present invention provides a method for preparing the modified asphalt described above, the method comprising: mechanically blending a modifier with a molten base asphalt.

[0027] A fifth aspect of the present invention provides a modified asphalt mixture, which comprises modified asphalt, aggregate and mineral powder; wherein the modified asphalt is the modified asphalt described above.

[0028] A sixth aspect of the present invention provides a method for preparing the modified asphalt mixture described above, the method comprising the following steps:

[0029] (1) Preheating the aggregate and mineral powder, and preheating the modified asphalt to a molten state;

[0030] (2) Add the molten modified asphalt and mineral powder to the aggregate in turn and mix them.

[0031] Compared with the prior art, the present invention has the following advantages:

[0032] (1) In the method described in the present invention, the silanol groups generated after the hydrolysis of the silane coupling agent react with the silanol groups on the surface of the retired wind turbine blade powder, thereby increasing the non-polar groups on the surface of the retired wind turbine blade powder. The silanol groups are then melt-blended with the elastomer in a certain proportion, so that the elastomer and the non-polar groups on its surface interact with each other to achieve chemical coating modification. The retired wind turbine blade powder is synergistically treated with the silane coupling agent and the elastomer, thereby improving the compatibility of the retired wind turbine blade powder with asphalt. By using the above method, the prepared anti-water damage asphalt modifier is used to prepare modified asphalt, which can increase the softening temperature of the asphalt to a certain extent, and will not significantly increase the viscosity to affect the working performance of the modified asphalt. The prepared modified asphalt is used to prepare a modified asphalt mixture, which can significantly improve the water stability of the asphalt mixture, and at the same time improve the permanent deformation resistance, high temperature performance and low temperature performance of the asphalt mixture, thereby achieving the high-quality improvement effect of the wind turbine blade asphalt modifier on the asphalt mixture.

[0033] (2) The water-damage resistant asphalt modifier prepared by the method of the present invention is low-cost and can be used to partially or completely replace the common polymer modifiers in the asphalt pavement field. It has significant cost advantages and can greatly reduce the economic costs incurred in road construction.

[0034] (3) The method of the present invention uses retired wind turbine blades as the main raw material to prepare asphalt modifiers, which can effectively solve the serious problems such as resource waste and environmental pollution caused by the wave of wind turbine blade retirement, and realize the large-scale development and resource utilization of retired wind turbine blades. It is a green and efficient recycling solution with significant economic benefits and engineering value. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] FIG1 is a process flow chart of a method for preparing a water-damage resistant asphalt modifier according to the present invention;

[0036] FIG2 is a SEM image of the retired wind turbine blade powder prepared in Example 1 of the present invention at a magnification of 500 times;

[0037] FIG3 is a SEM image of the retired electric blade powder prepared in Example 1 of the present invention at a magnification of 5000 times;

[0038] FIG4 is a SEM image of the water damage resistant asphalt modifier prepared in Example 1 of the present invention, magnified 500 times;

[0039] FIG5 is a SEM image of the water-damage resistant asphalt modifier prepared in Example 1 of the present invention, magnified 5000 times. DETAILED DESCRIPTION

[0040] The following describes the specific embodiments of the present invention in detail with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention and are not intended to limit the present invention.

[0041] The endpoints of the ranges and any values ​​disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoints of each range, the endpoints of each range and individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered to be specifically disclosed herein.

[0042] In one aspect, the present invention provides a method for preparing a water damage resistant asphalt modifier, as shown in FIG1 , the method comprising the following steps:

[0043] S1: Powdering and sieving retired wind turbine blades to obtain retired wind turbine blade powder;

[0044] S2: mixing the retired wind turbine blade powder in step S1 with a silane coupling agent hydrolyzed solution, and then drying to obtain silicified retired wind turbine blade powder;

[0045] S3: The siliconized retired wind turbine blade powder in step S2 is mixed with an elastomer, and then melt-blended, crushed and sieved to obtain a water-damage resistant asphalt modifier.

[0046] In the present invention, the main components of the retired wind turbine blades are glass fiber and epoxy resin.

[0047] In a preferred embodiment, in step S1, the content of glass fiber in the retired wind turbine blade is greater than 70% by weight.

[0048] In a preferred embodiment, in step S1, the retired wind turbine blades after the pulverization treatment are sieved through a 50-mesh sieve to obtain the sieve residue, and the particle size of the obtained retired wind turbine blade powder is ≤0.3 mm.

[0049] In a preferred embodiment, in step S2, the silane coupling agent hydrolysis solution is obtained by mixing the silane coupling agent, water and anhydrous ethanol.

[0050] According to some embodiments of the present invention, in step S2, the silane coupling agent hydrolysis solution is obtained by adding the silane coupling agent to a mixture of anhydrous ethanol and water, mixing, and standing at room temperature (15-30° C.) for 10-60 minutes; specifically, the standing time can be 10 minutes, 20 minutes, 30 minutes, 40 minutes, 50 minutes or 60 minutes.

[0051] In order to improve the hydrolysis effect of the silane coupling agent, in a preferred embodiment, in step S2, the weight ratio of the silane coupling agent, water and anhydrous ethanol is 14-19:6-11:100; specifically, the weight ratio of the silane coupling agent, water and anhydrous ethanol can be 14:6:100, 14:7:100, 14:8:100, 14:9:100, 14:10:100, 14:11:100, 15:6:100, 15:7:100, 15:8:100, 15:9:100, 15:10:100, 15:11:100, 16:6:100, 1 100, 19:6:100, 19:7:100, 19:8:100, 19:9:100, 19:10:100 or 19:11:100.

[0052] In a preferred embodiment, in step S2, the mixing method is water bath stirring, and the conditions include: the water bath temperature is 55-85°C, and the stirring time is 10-60 min; specifically, the water bath temperature can be 55°C, 60°C, 65°C, 70°C, 75°C, 80°C or 85°C, and the stirring time can be 10 min, 20 min, 30 min, 40 min, 50 min or 60 min.

[0053] In a preferred embodiment, in step S2, the silane coupling agent is selected from one or more of KH550, KH560, and KH570.

[0054] In order to further improve the chemical modification effect of retired wind turbine blade powder, in step S2, the weight ratio of the retired wind turbine blade powder to the silane coupling agent is 100:10-20; specifically, the weight ratio of the retired wind turbine blade powder to the silane coupling agent can be 100:10, 100:11, 100:11.7, 100:12, 100:12.2, 100:13, 100:14, 100:15, 100:16, 100:17, 100:17.5, 100:18, 100:19 or 100:20.

[0055] In a preferred embodiment, in step S2, drying is carried out in an oven, and the drying conditions include: a temperature of 85°C-125°C, and a time of 80 min-180 min; specifically, the temperature can be 85°C, 90°C, 95°C, 100°C, 105°C, 110°C, 115°C, 120°C or 125°C, and the time can be 80 min, 100 min, 120 min, 140 min, 160 min or 180 min.

[0056] In order to further improve the ability of the anti-water damage asphalt modifier to combine with the matrix asphalt, in a preferred embodiment, in step S3, the weight ratio of the siliconized retired wind turbine blade powder to the elastomer is 100:15-45; specifically, the weight ratio of the siliconized retired wind turbine blade powder to the elastomer can be 100:15, 100:20, 100:25, 100:30, 100:35, 100:38, 100:40 or 100:45.

[0057] In a preferred embodiment, the elastomer is selected from styrene-butadiene rubber (SBR), styrene-butadiene-styrene block copolymer (SBS), block copolymer of styrene and isoprene (SIS), hydrogenated styrene-butadiene block copolymer (SEBS), butyl rubber (IIR) or ethylene-vinyl acetate copolymer (EVA).

[0058] In a preferred embodiment, in step S3, the conditions for melt blending include: a temperature of 50-70°C, a rotation speed of 40-70 rpm, and a time of 15-40 min; specifically, the temperature may be 50°C, 55°C, 60°C, 65°C or 70°C, the rotation speed may be 40 rpm, 45 rpm, 50 rpm, 55 rpm, 60 rpm, 65 rpm or 70 rpm, and the time may be 15 min, 20 min, 25 min, 30 min, 35 min or 40 min.

[0059] In a preferred embodiment, in step S3, the crushing is freeze crushing.

[0060] In a preferred embodiment, in step S3, the water-damage resistant asphalt modifier is sieved through a 50-mesh sieve to obtain the sieve residue, and the particle size of the water-damage resistant asphalt modifier is ≤0.3 mm.

[0061] The water damage-resistant asphalt modifier prepared by the method described herein improves the compatibility of retired wind turbine blade powder with matrix asphalt by treating it with a hydrolyzed silane coupling agent solution and an elastomer. This improves the performance of the asphalt, and consequently, the workability and road performance of the asphalt mixture. This is likely due to the fact that the hydrolyzed silane coupling agent solution increases the non-polar groups on the surface of the retired wind turbine blade powder, allowing the elastomer to interact with these non-polar groups on its surface, achieving chemical coating modification. The technical effects described herein are achieved through the synergistic treatment of retired wind turbine blade powder with the silane coupling agent and the elastomer.

[0062] The second aspect of the present invention provides a water damage resistant asphalt modifier prepared by the above method.

[0063] In the present invention, the water damage resistant asphalt modifier prepared by the above method can be used alone or mixed with an existing asphalt modifier, for example, it can be mixed with SBS.

[0064] The third aspect of the present invention provides a modified asphalt, which comprises a base asphalt and a modifier, wherein the modifier is the water damage resistant asphalt modifier described above and optionally SBS.

[0065] In a preferred embodiment, the weight ratio of the modifier to the base asphalt is 1-20:100, more preferably 3-10:100; specifically, the weight ratio of the modifier to the base asphalt can be 3:100, 4:100, 5:100, 6:100, 7:100, 8:100, 9:100 or 10:100.

[0066] In a preferred embodiment, when the modifier is the anti-water damage asphalt modifier and SBS described above, the weight proportion of the anti-water damage asphalt modifier is 30-100% of the total weight of the modifier; specifically, it can be 30%, 40%, 50%, 60%, 70%, 80%, 90% or 100%.

[0067] A fourth aspect of the present invention provides a method for preparing the modified asphalt described above, the method comprising: mechanically blending a modifier with a molten base asphalt.

[0068] In order to improve the performance of the modified asphalt and ensure that the modifier is fully dispersed or dissolved and swelled in the base asphalt, in a preferred embodiment, the mechanical blending includes the following steps:

[0069] A1: High-speed shear stirring is performed using a high-speed shearing device with a shear rate of 2500-4000 r / min, a stirring time of 40-60 min, and a stirring temperature of 150-210°C;

[0070] A2: Low-speed shear stirring is performed using a low-speed shear device with a shear rate of 200-1500 r / min, a stirring time of 60-240 min, and a stirring temperature of 150-210°C.

[0071] In a specific embodiment, in step A1, the shear rate can be 2500 r / min, 3000 r / min, 3500 r / min or 4000 r / min; the stirring time can be 40 min, 50 min or 60 min; and the stirring temperature can be 150°C, 160°C, 170°C, 180°C, 190°C, 200°C or 210°C.

[0072] In a specific embodiment, in step A2, the shear rate can be 200 r / min, 500 r / min, 800 r / min, 1000 r / min or 1500 r / min; the stirring time can be 60 min, 120 min, 180 min or 240 min; and the stirring temperature can be 150°C, 160°C, 170°C, 180°C, 190°C, 200°C or 210°C.

[0073] A fifth aspect of the present invention provides a modified asphalt mixture, which comprises modified asphalt, aggregate and mineral powder; wherein the modified asphalt is the modified asphalt described above.

[0074] In the present invention, there is no special requirement for the selection of the aggregate and mineral powder, and they may be various aggregates and mineral powders conventionally used in the art.

[0075] A sixth aspect of the present invention provides a method for preparing the modified asphalt mixture described above, the method comprising the following steps:

[0076] (1) Preheating the aggregate and mineral powder, and preheating the modified asphalt to a molten state;

[0077] (2) Add the molten modified asphalt and mineral powder to the aggregate in turn and mix them.

[0078] In a preferred embodiment, in step (1), the preheating temperature of the aggregate and the mineral powder is 170-210°C, the preheating time is 1-8h, and the preheating temperature of the modified asphalt when it is preheated to a molten state is 165-190°C; specifically, the preheating temperature of the aggregate and the mineral powder can be 170°C, 180°C, 190°C, 200°C or 210°C, the preheating time can be 1h, 2h, 3h, 4h, 5h, 6h, 7h or 8h, and the preheating temperature of the modified asphalt when it is preheated to a molten state can be 165°C, 170°C, 175°C, 180°C, 185°C or 190°C.

[0079] In order to improve the working performance and road performance of asphalt mixture, in a preferred embodiment, in step (1), the weight ratio of the total weight of the aggregate and the mineral powder to the modified asphalt is 100:4-6; specifically, the weight ratio of the total weight of the aggregate and the mineral powder to the modified asphalt can be 100:4, 100:4.5, 100:5, 100:5.5 or 100:6.

[0080] In a preferred embodiment, in step (1), the weight proportion of the mineral powder is 4-6% of the total weight of the aggregate and the mineral powder; specifically, it can be 4%, 4.5%, 5%, 5.5% or 6%.

[0081] In a preferred embodiment, step (2) specifically includes the following steps:

[0082] B1: Mix the preheated aggregate for 5-25 seconds;

[0083] B2: Add the molten modified asphalt to the material obtained in step B1, and then stir for 10-60 seconds;

[0084] B3: Add the preheated mineral powder to the material obtained in step B2, and then stir for 60-300 seconds.

[0085] According to some embodiments of the present invention, the mixing processes in steps B1-B3 can all be performed in a stirring pot.

[0086] Further preferably, the mixing temperature in steps B1-B3 is independently 180-195°C; specifically, the mixing temperature can be 180°C, 185°C, 190°C or 195°C.

[0087] In a specific embodiment, in step B1, the mixing time can be 5s, 10s, 15s, 20s or 25s; in step B2, the mixing time can be 10s, 13s, 15s, 20s, 25s, 30s, 35s, 40s, 45s, 50s, 58s or 60s; in step B3, the mixing time can be 60s, 90s, 100s, 120s, 150s, 180s, 210s, 240s, 270s, 300s.

[0088] The following examples further illustrate the water damage resistance asphalt modifier, its preparation method, and application of the present invention. The examples are based on the technical solution of the present invention and provide detailed implementation methods and specific operating procedures. However, the scope of protection of the present invention is not limited to the following examples.

[0089] The experimental methods of the following examples, unless otherwise specified, are all conventional methods in the art. The experimental materials of the following examples, unless otherwise specified, are all commercially available.

[0090] Table 1

[0091] Note: 1. 1 Modifier dosage is the percentage of modifier to base asphalt weight; 2. 2 Asphalt-to-stone ratio is the percentage of modified asphalt or base asphalt to the total weight of aggregate and mineral powder; 3. 3 SBS dosage is the percentage of SBS in the modifier weight; 4. 4 The dosage of the anti-water damage asphalt modifier is the percentage of the anti-water damage asphalt modifier to the weight of the modifier.

[0092] Example 1

[0093] The modifier dosage, asphalt-to-stone ratio, SBS dosage and water damage resistance asphalt modifier dosage are shown in Table 1;

[0094] Preparation of anti-water damage asphalt modifier M1:

[0095] S1: Powder the retired wind turbine blades and sieve the residue through a 50-mesh sieve to obtain retired wind turbine blade powder (rWTB) with a particle size of ≤0.3 mm (see Figures 2 and 3 for micromorphology);

[0096] S2: KH550 was added to a mixed solution of anhydrous ethanol and water, and the mixture was allowed to stand at room temperature for 20 minutes to obtain a silane coupling agent hydrolysis solution, wherein the weight ratio of KH550, water and anhydrous ethanol was 15:8:100. Then, 100 g of rWTB obtained in step S1 was added to 100 g of the silane coupling agent hydrolysis solution, and the mixture was stirred in a 60°C water bath for 20 minutes to surface modify the rWTB. The mixture was then placed in an oven at 105°C and dried for 120 minutes to obtain siliconized retired wind turbine blade powder (Si-rWTB);

[0097] S3: 100 g of Si-rWTB obtained in step S2 was mixed with 20 g of styrene-butadiene rubber (SBR), and then melt blended at a temperature of 55° C., a rotation speed of 50 rpm, and a time of 20 min.

[0098] After melt blending is completed, the mixture is frozen and crushed, and then sieved through a 50-mesh sieve to obtain the anti-water damage asphalt modifier M1 with a particle size of ≤0.3 mm;

[0099] Preparation of modified asphalt N1:

[0100] A1: 0.08 kg of the water damage resistance asphalt modifier M1 prepared above was added to 2 kg of molten base asphalt and mechanically blended. First, high-speed shear stirring was performed at 170°C using a high-speed shearing device at a shear rate of 3000 r / min for 60 minutes.

[0101] A2: Continuing at 170°C, the product obtained in step A1 was transferred to a low-speed shear device for low-speed shear stirring at a shear rate of 500 r / min and a stirring time of 3 h to prepare modified asphalt N1;

[0102] Preparation of modified asphalt mixture L1:

[0103] (1) The AC type dense gradation commonly used in highway pavement was selected, and 20 kg of aggregate of corresponding size and mineral powder (the weight proportion of mineral powder was 4%) were weighed. Then, 20 kg of the aggregate was preheated in an oven at 180 °C for 3 h. At 170 °C, 0.8 kg of the modified asphalt N1 prepared above was preheated to a molten state.

[0104] (2) The aggregate was added to a stirring pot at 185°C and stirred for 10 seconds. Then, the molten modified asphalt N1 was added and stirred for 20 seconds. Finally, the preheated mineral powder was added and stirred for 90 seconds. The machine was stopped and the materials were unloaded to prepare the modified asphalt mixture L1.

[0105] Example 2

[0106] The modifier dosage, asphalt-to-stone ratio, SBS dosage and water damage resistance asphalt modifier dosage are shown in Table 1;

[0107] Preparation of anti-water damage asphalt modifier M2:

[0108] S1: Powder the retired wind turbine blades and sieve the residue through a 50-mesh sieve to obtain retired wind turbine blade powder (rWTB) with a particle size of ≤0.3 mm. The microscopic morphology of the powder is shown in Figures 2 and 3.

[0109] S2: KH550 was added to a mixed solution of anhydrous ethanol and water, and the mixture was allowed to stand at room temperature for 30 minutes to obtain a silane coupling agent hydrolysis solution, wherein the weight ratio of KH550, water, and anhydrous ethanol was 14:6:100. Then, 100 g of rWTB obtained in step S1 was added to 100 g of the silane coupling agent hydrolysis solution, and the mixture was stirred in a 65°C water bath for 30 minutes to surface modify the rWTB. The mixture was then placed in a 95°C oven and dried for 150 minutes to obtain siliconized retired wind turbine blade powder (Si-rWTB);

[0110] S3: 100 g of Si-rWTB obtained in step S2 was mixed with 25 g of styrene-butadiene rubber (SBR), and then melt blended at a temperature of 60° C., a rotation speed of 50 rpm, and a time of 25 min.

[0111] After the melt blending is completed, the mixture is frozen and crushed, and then sieved through a 50-mesh sieve to obtain the anti-water damage asphalt modifier M2 with a particle size of ≤0.3 mm;

[0112] Preparation of modified asphalt N2:

[0113] A1: 0.08 kg of the water damage resistance asphalt modifier M2 prepared above was added to 2 kg of molten base asphalt and mechanically blended. First, high-speed shear stirring was performed at 180°C using a high-speed shearing device at a shear rate of 3500 r / min for 60 min.

[0114] A2: Continuing at 180°C, the product obtained in step A1 was transferred to a low-speed shear device for low-speed shear stirring at a shear rate of 500 r / min and a stirring time of 3 h to prepare modified asphalt N2;

[0115] Preparation of modified asphalt mixture L2:

[0116] (1) Select the AC type dense gradation commonly used in highway pavement, weigh 20 kg of aggregate of corresponding size and mineral powder (the weight proportion of mineral powder is 5%), and then preheat it in an oven at 185°C for 4 hours. At 170°C, preheat 1 kg of the modified asphalt N2 prepared above to a molten state;

[0117] (2) The aggregate was added to a stirring pot at 185°C and stirred for 20 seconds. Then, molten modified asphalt N2 was added and stirred for 30 seconds. Finally, preheated mineral powder was added and stirred for 160 seconds. The machine was stopped and the materials were unloaded to prepare the modified asphalt mixture L2.

[0118] Example 3

[0119] The modifier dosage, asphalt-to-stone ratio, SBS dosage and water damage resistance asphalt modifier dosage are shown in Table 1;

[0120] Preparation of anti-water damage asphalt modifier M3:

[0121] S1: Powder the retired wind turbine blades and sieve the residue through a 50-mesh sieve to obtain retired wind turbine blade powder (rWTB) with a particle size of ≤0.3 mm;

[0122] S2: KH550 was added to a mixed solution of anhydrous ethanol and water, and the mixture was allowed to stand at room temperature for 30 minutes to obtain a silane coupling agent hydrolysis solution, wherein the weight ratio of KH550, water, and anhydrous ethanol was 19:11:100. Then, 100 g of rWTB obtained in step S1 was added to 120 g of the silane coupling agent hydrolysis solution, and the mixture was stirred in a 70°C water bath for 40 minutes to surface modify the rWTB. The mixture was then placed in an oven at 115°C and dried for 100 minutes to obtain siliconized retired wind turbine blade powder (Si-rWTB);

[0123] S3: 100 g of Si-rWTB obtained in step S2 was mixed with 30 g of styrene-butadiene rubber (SBR), and then melt blended at a temperature of 65° C., a rotation speed of 55 rpm, and a time of 25 min.

[0124] After melt blending is completed, the mixture is frozen and crushed, and then sieved through a 50-mesh sieve to obtain the anti-water damage asphalt modifier M3 with a particle size of ≤0.3 mm;

[0125] Preparation of modified asphalt N3:

[0126] A1: 0.08 kg of the water damage resistance asphalt modifier M3 prepared above was added to 2 kg of molten base asphalt for mechanical blending. First, high-speed shear stirring was performed at 175°C using a high-speed shearing device at a shear rate of 3000 r / min for 100 min.

[0127] A2: Continuing at 175°C, the product obtained in step A1 was transferred to a low-speed shear device for low-speed shear stirring at a shear rate of 800 r / min for 3 h to prepare modified asphalt N3;

[0128] Preparation of modified asphalt mixture L3:

[0129] (1) Select the AC type dense gradation commonly used in highway pavement, weigh 20 kg of aggregate of corresponding size and mineral powder (the weight proportion of mineral powder is 6%), and then preheat it in an oven at 190°C for 6 hours. At 180°C, preheat 1.2 kg of the modified asphalt N3 prepared above to a molten state;

[0130] (2) The aggregate was added to a stirring pot at 190°C and stirred for 15 seconds. Then, the molten modified asphalt N3 was added and stirred for 25 seconds. Finally, the preheated mineral powder was added and stirred for 100 seconds. The machine was stopped and the materials were unloaded to prepare the modified asphalt mixture L3.

[0131] Example 4

[0132] The modifier dosage, asphalt-to-stone ratio, SBS dosage and water damage resistance asphalt modifier dosage are shown in Table 1;

[0133] Preparation of modified asphalt mixture L4:

[0134] (1) Select the AC type dense gradation commonly used in highway pavement, weigh 20 kg of aggregate of corresponding size and mineral powder, and then preheat it in an oven at 180°C for 3 hours. Preheat 1 kg of modified asphalt N1 prepared in Example 1 at 170°C until it is molten;

[0135] (2) The aggregate was added to a stirring pot at 185°C and stirred for 10 seconds. Then, the molten modified asphalt N1 was added and stirred for 20 seconds. Finally, the preheated mineral powder was added and stirred for 90 seconds. The machine was stopped and the materials were unloaded to prepare the modified asphalt mixture L4.

[0136] Example 5

[0137] The modifier dosage, asphalt-to-stone ratio, SBS dosage and water damage resistance asphalt modifier dosage are shown in Table 1;

[0138] Preparation of modified asphalt mixture L5:

[0139] (1) Select the AC type dense gradation commonly used in highway pavement, weigh 20 kg of aggregate of corresponding size and mineral powder, and then preheat it in an oven at 180°C for 3 hours. Preheat 1.2 kg of modified asphalt N1 prepared in Example 1 at 170°C until it is molten;

[0140] (2) The aggregate was added to a stirring pot at 185°C and stirred for 10 seconds. Then, the molten modified asphalt N1 was added and stirred for 20 seconds. Finally, the preheated mineral powder was added and stirred for 90 seconds. The machine was stopped and the materials were unloaded to prepare the modified asphalt mixture L5.

[0141] Example 6

[0142] The modifier dosage, asphalt-to-stone ratio, SBS dosage and water damage resistance asphalt modifier dosage are shown in Table 1;

[0143] Preparation of modified asphalt N6:

[0144] A1: 0.1 kg of the water damage resistance asphalt modifier M2 prepared in Example 2 was added to 2 kg of molten base asphalt and mechanically blended. First, high-speed shear stirring was performed at 180°C using a high-speed shearing device at a shear rate of 3500 r / min for 60 min.

[0145] A2: Continuing at 180°C, the product obtained in step A1 was transferred to a low-speed shear device for low-speed shear stirring at a shear rate of 500 r / min and a stirring time of 3 h to prepare modified asphalt N6;

[0146] Preparation of modified asphalt mixture L6:

[0147] (1) Select the AC type dense gradation commonly used in highway pavement, weigh 20 kg of aggregate of corresponding size and mineral powder (the weight proportion of mineral powder is 5%), and then preheat it in an oven at 185°C for 4 hours. At 170°C, preheat 1 kg of the modified asphalt N6 prepared above to a molten state;

[0148] (2) The aggregate was added to a stirring pot at 185°C and stirred for 20 seconds. Then, the molten modified asphalt N6 was added and stirred for 30 seconds. Finally, the preheated mineral powder was added and stirred for 160 seconds. The machine was stopped and the materials were unloaded to prepare the modified asphalt mixture L6.

[0149] Example 7

[0150] The modifier dosage, asphalt-to-stone ratio, SBS dosage and water damage resistance asphalt modifier dosage are shown in Table 1;

[0151] Preparation of modified asphalt N7:

[0152] A1: 0.12 kg of the water damage resistance asphalt modifier M2 prepared in Example 2 was added to 2 kg of molten base asphalt and mechanically blended. First, high-speed shear stirring was performed at 180°C using a high-speed shearing device at a shear rate of 3500 r / min for 60 min.

[0153] A2: Continuing at 180°C, the product obtained in step A1 was transferred to a low-speed shear device for low-speed shear stirring at a shear rate of 500 r / min and a stirring time of 3 h to prepare modified asphalt N7;

[0154] Preparation of modified asphalt mixture L7:

[0155] (1) The AC type dense gradation commonly used in highway pavement was selected, and 20 kg of aggregate of corresponding size and mineral powder (the weight proportion of mineral powder was 5%) was weighed, and then placed in an oven at 185 ° C for 4 h. At 170 ° C, 1 kg of the modified asphalt N7 prepared above was preheated to a molten state;

[0156] (2) The aggregate was added to a stirring pot at 185°C and stirred for 20 seconds. Then, the molten modified asphalt N7 was added and stirred for 30 seconds. Finally, the preheated mineral powder was added and stirred for 160 seconds. The machine was stopped and the materials were unloaded to prepare the modified asphalt mixture L7.

[0157] Example 8

[0158] The modifier dosage, asphalt-to-stone ratio, SBS dosage and water damage resistance asphalt modifier dosage are shown in Table 1;

[0159] Preparation of modified asphalt N8:

[0160] A1: 0.03 kg of the water damage resistant asphalt modifier M3 prepared in Example 3 and 0.07 kg of SBS were added to 2 kg of molten base asphalt and mechanically blended. First, high-speed shear stirring was performed at 175°C using a high-speed shearing device at a shear rate of 3000 r / min for 100 min.

[0161] A2: Continuing at 175°C, the product obtained in step A1 was transferred to a low-speed shear device for low-speed shear stirring at a shear rate of 800 r / min and a stirring time of 3 h to prepare modified asphalt N8;

[0162] Preparation of modified asphalt mixture L8:

[0163] (1) The AC type dense gradation commonly used in highway pavement was selected, and 20 kg of aggregate of corresponding size and mineral powder (the weight proportion of mineral powder was 6%) was weighed, and then placed in an oven at 190 ° C for 6 h. At 180 ° C, 1 kg of the modified asphalt N8 prepared above was preheated to a molten state;

[0164] (2) The aggregate was added to a stirring pot at 190°C and stirred for 15 seconds. Then, the molten modified asphalt N8 was added and stirred for 25 seconds. Finally, the preheated mineral powder was added and stirred for 100 seconds. The machine was stopped and the materials were unloaded to prepare the modified asphalt mixture L8.

[0165] Example 9

[0166] The modifier dosage, asphalt-to-stone ratio, SBS dosage and water damage resistance asphalt modifier dosage are shown in Table 1;

[0167] Preparation of modified asphalt N9:

[0168] A1: 0.07 kg of the water damage resistant asphalt modifier M3 prepared in Example 3 and 0.03 kg of SBS were added to 2 kg of molten base asphalt and mechanically blended. First, high-speed shear stirring was performed at 175°C using a high-speed shearing device at a shear rate of 3000 r / min for 100 min.

[0169] A2: Continuing at 175°C, the product obtained in step A1 was transferred to a low-speed shear device for low-speed shear stirring at a shear rate of 800 r / min and a stirring time of 3 h to prepare modified asphalt N9;

[0170] Preparation of modified asphalt mixture L9:

[0171] (1) The AC type dense gradation commonly used in highway pavement was selected, and 20 kg of aggregate of corresponding size and mineral powder (the weight proportion of mineral powder was 6%) was weighed, and then placed in an oven at 190 ° C for 6 h. At 180 ° C, 1 kg of the modified asphalt N9 prepared above was preheated to a molten state;

[0172] (2) The aggregate was added to a stirring pot at 190°C and stirred for 15 seconds. Then, the molten modified asphalt N9 was added and stirred for 25 seconds. Finally, the preheated mineral powder was added and stirred for 100 seconds. The machine was stopped and the materials were unloaded to prepare the modified asphalt mixture L9.

[0173] Example 10

[0174] The modifier dosage, asphalt-to-stone ratio, SBS dosage and water damage resistance asphalt modifier dosage are shown in Table 1;

[0175] Preparation of anti-water damage asphalt modifier M10:

[0176] The method of Example 2 was followed, except that 10 g of styrene-butadiene rubber (SBR) was used instead of 25 g of styrene-butadiene rubber (SBR) in step S3 to obtain an anti-water damage asphalt modifier M10.

[0177] Preparation of modified asphalt N10:

[0178] The method of Example 2 was followed, except that the anti-water damage asphalt modifier M10 was used in place of the anti-water damage asphalt modifier M2 by the same weight to obtain modified asphalt N10.

[0179] Preparation of modified asphalt mixture L10:

[0180] The method of Example 2 was followed, except that the modified asphalt N2 was replaced by the modified asphalt N10 of the same weight to obtain the modified asphalt mixture L10.

[0181] Example 11

[0182] The modifier dosage, asphalt-to-stone ratio, SBS dosage and water damage resistance asphalt modifier dosage are shown in Table 1;

[0183] Preparation of anti-water damage asphalt modifier M11:

[0184] The method of Example 3 was followed, except that in step S2, the weight ratio of KH550, water, and anhydrous ethanol was 20:11:100, to obtain an anti-water damage asphalt modifier M11.

[0185] Preparation of modified asphalt N11:

[0186] The method of Example 3 was followed, except that the anti-water damage asphalt modifier M11 was used in place of the anti-water damage asphalt modifier M3 by the same weight to obtain modified asphalt N11.

[0187] Preparation of modified asphalt mixture L11:

[0188] The method of Example 3 was followed, except that the modified asphalt N3 was replaced by the modified asphalt N11 of the same weight to obtain the modified asphalt mixture L11.

[0189] Example 12

[0190] The modifier dosage, asphalt-to-stone ratio, SBS dosage and water damage resistance asphalt modifier dosage are shown in Table 1;

[0191] Preparation of anti-water damage asphalt modifier M12:

[0192] The method of Example 3 was followed, except that 10 g of styrene-butadiene rubber (SBR) was used instead of 25 g of styrene-butadiene rubber (SBR) in step S3 to obtain a water-damage resistant asphalt modifier M12.

[0193] Preparation of modified asphalt N12:

[0194] The method of Example 8 was followed, except that the anti-water damage asphalt modifier M12 was used in place of the anti-water damage asphalt modifier M3 by the same weight to obtain modified asphalt N12.

[0195] Preparation of modified asphalt mixture L12:

[0196] The method of Example 8 was followed, except that the modified asphalt N8 was replaced by the modified asphalt N12 of the same weight to obtain the modified asphalt mixture L12.

[0197] Example 13

[0198] The modifier dosage, asphalt-to-stone ratio, SBS dosage and water damage resistance asphalt modifier dosage are shown in Table 1;

[0199] Preparation of anti-water damage asphalt modifier M13:

[0200] The method of Example 3 was followed, except that in step S2, the weight ratio of KH550, water, and anhydrous ethanol was 20:11:100, to obtain the water-damage resistant asphalt modifier M13;

[0201] Preparation of modified asphalt N13:

[0202] The method of Example 8 was followed, except that the anti-water damage asphalt modifier M13 was used in place of the anti-water damage asphalt modifier M3 by the same weight to obtain modified asphalt N13.

[0203] Preparation of modified asphalt mixture L13:

[0204] The method of Example 8 was followed, except that the modified asphalt N13 of the same weight was used instead of the modified asphalt N8 to obtain the modified asphalt mixture L13.

[0205] Test Case

[0206] 1. The morphology of the water-damage-resistant asphalt modifier prepared in Example 1 was tested using a scanning electron microscope. The test results are shown in Figures 4-5. Figure 4 is a SEM image of the water-damage-resistant asphalt modifier prepared in Example 1 at a magnification of 500 times; Figure 5 is a SEM image of the water-damage-resistant asphalt modifier prepared in Example 1 at a magnification of 5000 times;

[0207] It can be seen from Figures 4-5 that compared with the SEM images of retired wind turbine blade powder (Figures 2-3), the microstructure of the anti-water damage asphalt modifier prepared in Example 1 of the present invention realizes a composite structure of elastomer-coated retired wind turbine blade powder, and the surface is relatively rough, thus having better compatibility with asphalt.

[0208] 2. The properties of the base asphalt and the modified asphalt obtained in Examples 1-13 were tested. The test indicators included softening point, ductility and viscosity. The test results are shown in Table 2.

[0209] Table 2

[0210] The data in Table 2 indicate that the water-damage-resistant asphalt modifier prepared in the present invention significantly increases the softening point, slightly improves the ductility, and somewhat increases the viscosity of modified asphalt when used in the preparation of modified asphalt. This demonstrates that the water-damage-resistant asphalt modifier prepared in the present invention can enhance asphalt's high-temperature resistance and improve its ductility to a certain extent without significantly affecting its high-temperature performance. Furthermore, the water-damage-resistant asphalt modifier prepared in the present invention exhibits excellent synergy when used in combination with an SBS modifier, promoting improvements in the overall performance of asphalt without any exclusionary effect. Overall, the water-damage-resistant asphalt modifier prepared in the present invention has a favorable modification effect on asphalt.

[0211] 3. The properties of the modified asphalt mixtures obtained in Examples 1-13 were tested. The test indicators included the Marshall residual stability under immersion, dynamic stability, and maximum flexural strain. The test results are shown in Table 3.

[0212] (1) Marshall residual stability after immersion: According to the test method of "Test Procedure for Asphalt and Asphalt Mixtures for Highway Engineering" (JTG E20-2011 T 0702), the modified asphalt mixtures prepared in Examples 1-13 were subjected to Marshall specimen preparation by the compaction method. According to the test method of "Test Procedure for Asphalt and Asphalt Mixtures for Highway Engineering" (JTG E20-2011 T 0709), the Marshall stability tester was used to test the Marshall stability of the above-mentioned asphalt mixture specimens. The difference between the immersion Marshall test and the above-mentioned test is that the specimens need to be kept warm in a constant temperature water tank at 60°C for 48 hours. Furthermore, the percentage of the ratio of the Marshall stability after immersion to the Marshall stability before immersion is used as the immersion Marshall residual stability, which is used to evaluate the water stability of the above-mentioned asphalt mixture. The larger the value, the better the water stability;

[0213] (2) Dynamic stability: According to the test method of "Test Procedure for Asphalt and Asphalt Mixtures in Highway Engineering" (JTG E20-2011 T 0719), the asphalt mixture rutting specimens prepared in Examples 1-13 were subjected to high-temperature stability tests under the test conditions of a temperature of 60°C and a wheel pressure of 0.7 MPa. Dynamic stability was used as the main indicator to evaluate the high-temperature deformation resistance of the specimens.

[0214] (3) Maximum flexural strain: According to the test method of "Test Procedure for Asphalt and Asphalt Mixtures in Highway Engineering" (JTG E20-2011 T 0715), the asphalt mixture specimens prepared in Examples 1-13 were tested at a low temperature of -10°C and a loading rate of 50 mm / min. The low-temperature performance of the specimens was evaluated by the maximum flexural strain at the time of specimen failure.

[0215] Table 3

[0216] The data in Table 3 show that the modified asphalt prepared by the present invention is used to prepare modified asphalt mixtures. The modified asphalt mixtures prepared in Examples 1-9 and 12-13 all meet the road use requirements (≥85%) in terms of water-immersion Marshall residual stability. In some preferred embodiments, the value exceeds 94%, and the high-temperature performance of the modified asphalt mixtures is also significantly improved. In addition, for the low-temperature maximum bending strain, the water-damage-resistant asphalt modifiers prepared in Examples 1-9 and 12-13 meet the standard technical requirements (≥2500). Overall, the asphalt mixture modified with the water-damage-resistant asphalt modifier prepared by the present invention has good road performance, especially in terms of improving water stability.

[0217] 4. The economic benefits of the application of the water damage resistant asphalt modifier of the present invention in road engineering materials were analyzed, using the commonly used asphalt modifier SBS as a reference. The costs of the two are shown in Table 4.

[0218] Table 4

[0219] From the data in Table 4, we can see that the estimated unit price of water-damage resistant asphalt modifier with a particle size of less than 0.3 mm is 3,615 yuan / ton, while the unit price of modifier SBS is 15,800 yuan / ton. Therefore, the cost difference between the two is 12,185 yuan / ton.

[0220] For the above cost analysis, assuming that a 1km two-way four-lane road (length 1000m × width 12m × thickness 0.17m = 2040m) is laid 3 ) asphalt pavement, according to the commonly used mix ratio of the project, it requires approximately 5140.8 tons of asphalt mixture and 11.75 tons of asphalt modifier; in view of this, the cost of using the modifier SBS is about 185,700 yuan, while the cost of using the anti-water damage asphalt modifier of the present invention is about 42,500 yuan. In summary, the cost of paving 1 km of two-way four-lane road (length 1000m×width 12m×thickness 0.17m=2040m 3 )'s asphalt pavement can save 143,200 yuan, which has significant economic benefits and engineering value.

[0221] Therefore, the water-damage resistant asphalt modifier of the present invention can reduce the use of the modifier SBS and greatly reduce the economic costs incurred in road construction. The technical solution of preparing modified asphalt and modified asphalt mixture using the water-damage resistant asphalt modifier of the present invention has significant economic benefits.

[0222] The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, various simple variations of the technical solution of the present invention may be made, including combining the various technical features in any other appropriate manner. These simple variations and combinations should also be regarded as disclosed in the present invention and fall within the scope of protection of the present invention.

Claims

1. A method for preparing a water-damage resistant asphalt modifier, characterized in that: The method comprises the following steps: S1: Powdering and sieving the retired wind turbine blades to obtain retired wind turbine blade powder; S2: mixing the retired wind turbine blade powder in step S1 with the hydrolysis solution of the silane coupling agent, and then drying to obtain siliconized retired wind turbine blade powder; S3: The siliconized retired wind turbine blade powder in step S2 is mixed with an elastomer, and then melt-blended, crushed and sieved to obtain a water-damage resistant asphalt modifier.

2. The method according to claim 1, characterized in that In step S1, the content of glass fiber in the retired wind turbine blade is greater than 70% by weight.

3. The method according to claim 1 or 2, characterized in that: In step S1, the particle size of the retired wind turbine blade powder is ≤0.3 mm.

4. The method according to claim 1, characterized in that In step S2, the silane coupling agent hydrolysis solution is obtained by mixing the silane coupling agent, water and anhydrous ethanol, wherein the weight ratio of the silane coupling agent, water and anhydrous ethanol is 14-19:6-11:100; Preferably, the weight ratio of the retired wind turbine blade powder to the silane coupling agent is 100:10-20.

5. The method according to claim 1 or 4, characterized in that: In step S2, the mixing conditions include: temperature of 55-85°C and time of 10-60 min.

6. The method according to claim 1, characterized in that In step S3, the weight ratio of the siliconized retired wind turbine blade powder to the elastomer is 100:15-45; Preferably, the elastomer is selected from SBR, SBS, SIS, SEBS, IIR or EVA.

7. The method according to claim 1 or 6, characterized in that: In step S3, the melt blending conditions include: temperature of 50-70°C, rotation speed of 40-70 rpm, and time of 15-40 min; Preferably, the crushing is freeze-crushing.

8. The method according to claim 1, characterized in that In step S3, the particle size of the water-damage resistant asphalt modifier is ≤0.3 mm.

9. The water damage resistant asphalt modifier prepared by the method according to any one of claims 1 to 8.

10. A modified asphalt, characterized in that: The modified asphalt comprises base asphalt and a modifier, wherein the modifier is the anti-water damage asphalt modifier according to claim 9 and optionally SBS.

11. The modified asphalt according to claim 10, characterized in that: The weight ratio of the modifier to the base asphalt is 1-20:

100.

12. A method for preparing the modified asphalt according to claim 10 or 11, characterized in that: The method comprises: mechanically mixing a modifier with a molten base asphalt.

13. A modified asphalt mixture, characterized in that: The modified asphalt mixture comprises modified asphalt, aggregate and mineral powder; Wherein, the modified asphalt is the modified asphalt according to claim 10 or 11.

14. A method for preparing the modified asphalt mixture according to claim 13, characterized in that: The method comprises the following steps: (1) Preheating aggregate and mineral powder, and preheating modified asphalt to a molten state; (2) Add the molten modified asphalt and mineral powder to the aggregate in turn and mix them.

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