A regeneration agent for hot regeneration of asphalt pavement and preparation method thereof

Abstract

The present application relates to the technical field of road construction, and specifically discloses a regeneration agent for hot regeneration of asphalt pavement and a preparation method thereof. In the regeneration agent of the present application, styrene-butadiene latex can form a network structure in asphalt, enhance the strength and toughness of the asphalt film, and resist the applied stress to a certain extent, hindering the plastic deformation of asphalt. At the same time, diatomaceous earth can adsorb the aromatic and saturated components in asphalt, and to a certain extent restrict the flow of asphalt. Under the joint action of styrene-butadiene latex and diatomaceous earth, the regeneration agent of the present application can make the hot regenerated asphalt have good anti-rutting performance, which is conducive to the promotion of asphalt hot regeneration technology.

Description

Technical Field

[0001] The present application relates to the technical field of road construction, and more specifically, to a regeneration agent for hot regeneration of asphalt pavement and a preparation method thereof. Background Art

[0002] Asphalt pavement is a composite material made of asphalt materials (usually petroleum asphalt or coal asphalt) mixed with aggregates (such as crushed stone, sand, etc.), and is famous for its excellent physical properties, economy, construction convenience and good durability. Due to the influence of factors such as traffic load, climate change, and material aging, asphalt pavement will develop cracks, potholes, rutting and other defects during use, and traditional maintenance methods generally have defects such as high cost and long construction period. Thermal regeneration technology is a type of asphalt pavement regeneration technology. It mainly heats and softens the old asphalt material, and then adds a specific regeneration agent to restore or improve the performance of the asphalt material. It is a sustainable pavement maintenance strategy.

[0003] In the related art, there is a regeneration agent for hot-regeneration of asphalt in situ, which includes the following components by weight: 35 parts of furfural extracted oil, 35 parts of waste cooking oil, 24 parts of epoxy fatty acid methyl ester, 5 parts of distilled tall oil, and 1 part of methyl silicone oil. In the asphalt hot regeneration process, the amount of this regeneration agent is usually 6% of the weight of the old asphalt in the waste asphalt pavement material, and the obtained asphalt hot regeneration mixture can have a certain anti-stripping performance.

[0004] With respect to the above-mentioned related technologies, the inventor believes that although the regeneration agent in the related technologies can be applied to the asphalt thermal regeneration process, plasticizers are often added in the asphalt thermal regeneration process. Although oil and plasticizers can improve the fluidity of aged asphalt, the anti-rutting performance of asphalt will decrease as the regeneration proceeds, making the asphalt pavement paved with asphalt thermal regeneration mixture more prone to rutting during service, which is not conducive to the promotion of asphalt thermal regeneration technology. Summary of the invention

[0005] In the related art, although the combination of oil and plasticizer can improve the fluidity of aged asphalt, it will also cause the anti-rutting performance of asphalt to decrease as the regeneration proceeds, which is not conducive to the promotion of asphalt thermal regeneration technology. In order to improve this defect, the present application provides a regeneration agent for thermal regeneration of asphalt pavement and a preparation method thereof.

[0006] In the first aspect, the present application provides a regeneration agent for hot regeneration of asphalt pavement, adopting the following technical scheme: a regeneration agent for hot regeneration of asphalt pavement, comprising the following components in parts by weight: 68.5-76.5 parts of oil, 17.6-22.8 parts of styrene-butadiene latex, 3.3-3.5 parts of plasticizer, and 72-90 parts of diatomaceous earth; the oil comprises furfural extracted oil and waste cooking oil, the weight of the furfural extracted oil accounts for 40-44% of the total weight of the oil, and the plasticizer comprises dimethyl phthalate.

[0007] By adopting the above technical scheme, the present application adds diatomite and styrene butadiene latex on the basis of oil and plasticizer, and obtains a new regeneration agent formula. When the aged asphalt is thermally regenerated, the oil supplements the light oil component lost by the aged asphalt, and the plasticizer further enhances the deformability of the aged asphalt. The combined effect of the oil and the plasticizer causes the anti-rutting performance of the thermally regenerated asphalt to have a downward trend, while styrene butadiene latex has good compatibility with asphalt. The addition of styrene butadiene latex can form a network structure in the asphalt, which enhances the strength and toughness of the asphalt film. This network structure can resist the applied stress to a certain extent and hinder the plastic deformation of the asphalt. At the same time, diatomite can absorb the aromatic and saturated components in the asphalt, which limits the flow of the asphalt to a certain extent. Through the combination of diatomite and styrene butadiene latex, the regeneration agent of the present application can make the thermally regenerated asphalt have good anti-rutting performance, which is conducive to the promotion of asphalt thermal regeneration technology. In addition, diatomaceous earth can absorb asphalt and odors in waste cooking oil, reducing the emission of volatile organic compounds. The use of waste cooking oil can provide a new way to dispose of catering waste, which has positive significance for green environmental protection.

[0008] Preferably, the regeneration agent further comprises a silane coupling agent, and the amount of the silane coupling agent is 4.3-4.6% of the weight of the oil.

[0009] By adopting the above-mentioned technical scheme, the present application adds silane coupling agent to the formula system of the regeneration agent. The addition of silane coupling agent can improve the dispersion effect of diatomaceous earth, so that diatomaceous earth can better play the role of adsorption of aromatic components and saturated components, which helps to improve the anti-rutting performance of hot-regenerated asphalt.

[0010] Preferably, the specific surface area of ​​the diatomaceous earth is 25-65m 2 / g.

[0011] By adopting the above technical solution, the present application limits the specific surface area range of diatomaceous earth, thereby achieving improvement in the anti-rutting performance of thermally regenerated asphalt.

[0012] Preferably, the specific surface area of ​​the diatomaceous earth is 45-65m 2 / g.

[0013] By adopting the above technical solution, the present application further optimizes the specific surface area of ​​diatomaceous earth when adding a silane coupling agent, which helps to give full play to the adsorption effect of diatomaceous earth and improve the anti-rutting performance of thermally regenerated asphalt.

[0014] Preferably, the regeneration agent further comprises carbon black, and the amount of the carbon black is 47-70% of the weight of the oil.

[0015] By adopting the above technical solution, the present application preferably uses carbon black as a component of the regeneration agent. The addition of carbon black can improve the ability of asphalt to resist deformation to a certain extent, and help improve the anti-rutting performance of thermally regenerated asphalt.

[0016] Preferably, the regeneration agent further comprises aluminum hydroxide, and the amount of the aluminum hydroxide used is 32-63% of the weight of the oil.

[0017] By adopting the above technical solution, the present application preferably uses aluminum hydroxide as a component of the regeneration agent. Aluminum hydroxide can enhance the asphalt's resistance to permanent deformation and help improve the anti-rutting performance of thermal regeneration cooling.

[0018] Preferably, the amount of aluminum hydroxide used is 48-63% of the weight of the oil.

[0019] By adopting the above technical solution, the present application optimizes the dosage of aluminum hydroxide, which helps to improve the anti-rutting performance of hot-regenerated asphalt.

[0020] Preferably, the regeneration agent further comprises wollastonite fibers, and the amount of the wollastonite fibers used is 13-22% of the weight of the oil.

[0021] By adopting the above technical solution, the wollastonite fiber is alkaline and can be interspersed in the asphalt and combined with the acidic components in the asphalt to form a three-dimensional network structure, which makes the asphalt have better resistance to shear deformation and helps to improve the anti-rutting performance of hot-regenerated asphalt.

[0022] Preferably, the amount of wollastonite fiber used is 15-20% of the weight of the oil.

[0023] By adopting the above technical solution, the present application optimizes the dosage of wollastonite fiber, which helps to improve the anti-rutting performance of thermally regenerated asphalt.

[0024] In a second aspect, the present application provides a method for preparing a regeneration agent for thermal regeneration of asphalt pavement, using the following technical solution.

[0025] A method for preparing a regeneration agent for hot regeneration of an asphalt pavement comprises the following steps:

[0026] (1) Heat the oil to 80-90°C and set aside;

[0027] (2) adding other components except the oil to the oil, and obtaining a mixture after heat preservation and stirring;

[0028] (3) The mixture is heated to 100-120° C. and stirred to obtain a regeneration agent for hot regeneration of asphalt pavement.

[0029] By adopting the above technical solution, the present application first preheats the oil, then adds the remaining raw material components into the oil for dispersion, and obtains the regeneration agent for thermal regeneration of asphalt pavement after further heating.

[0030] In summary, this application has the following beneficial effects:

[0031] 1. In the regeneration agent of the present application, styrene butadiene latex can form a network structure in asphalt, enhance the strength and toughness of the asphalt film, and resist the applied stress to a certain extent, hindering the plastic deformation of asphalt. At the same time, diatomaceous earth can absorb the aromatic and saturated components in asphalt, and to a certain extent restrict the flow of asphalt. Under the joint action of styrene butadiene latex and diatomaceous earth, the regeneration agent of the present application can make the hot regenerated asphalt have good anti-rutting performance, which is conducive to the promotion of asphalt hot regeneration technology.

[0032] 2. In this application, carbon black, aluminum hydroxide and wollastonite fiber are preferably selected as components of the regeneration agent, and the dosage of these components is optimized, which helps to improve the anti-rutting performance of the hot-regenerated asphalt. DETAILED DESCRIPTION

[0033] The present application is further described in detail below in conjunction with embodiments, preparation examples and comparative examples. The raw materials involved in the present application can all be obtained commercially.

[0034] Example

[0035] Examples 1-5

[0036] The following description is given by taking Example 1 as an example.

[0037] Example 1

[0038] This embodiment provides a regeneration agent for hot regeneration of asphalt pavement, including the following components: 68.5 kg of oil, 17.6 kg of styrene-butadiene latex, 3.3 kg of plasticizer, and 72 kg of diatomaceous earth. The plasticizer is dimethyl phthalate, the oil is composed of furfural extracted oil and waste edible oil, and the proportion of furfural extracted oil in the oil is 40% (referred to as furfural extracted oil proportion in Table 1); the waste edible oil is frying oil for fried food, the fresh crude oil corresponding to the waste edible oil is edible soybean oil, and the density of the waste edible oil (20°C) is 0.935 g / cm 3 , the dynamic viscosity is 0.175Pa·s; the kinematic viscosity of furfural extracted oil is 5.08mm2 / s, density (20℃) is 0.922g / cm 3 The pH value of styrene-butadiene latex is 7.35, the solid content is 47%, the particle size is 0.18 μm, the dynamic viscosity is 35 mPa·s, and the density is 0.93 g / cm 3 ; The specific surface area of ​​diatomaceous earth is 25m 2 / g.

[0039] This embodiment also provides a method for preparing a regeneration agent for hot regeneration of an asphalt pavement, comprising the following steps:

[0040] (1) Heat the oil to 80°C (referred to as preheating temperature in Table 1) and set aside;

[0041] (2) adding the other components except the oil to the oil, and stirring at a rate of 500 r / min for 30 min to obtain a mixture;

[0042] (3) The mixture was heated to 100° C. (referred to as the heating temperature in Table 1) and stirred at a rate of 500 r / min for 1 h to obtain a regeneration agent for hot regeneration of asphalt pavement.

[0043] As shown in Table 1, the differences between Examples 1-5 mainly lie in the different raw material ratios of the regeneration agent and some production and processing parameters.

[0044] Table 1 Raw material ratio and production and processing parameters

[0045] sample Example 1 Example 2 Example 3 Example 4 Example 5 Oil / kg 68.5 70.5 72.5 74.5 76.5 Furfural extracted oil percentage / % 40 41 42 43 44 Styrene butadiene latex / kg 17.6 18.8 20.4 21.6 22.8 Plasticizer / kg 3.3 3.35 3.4 3.45 3.5 Diatomaceous earth / kg 72 77 81 86 90 Preheating temperature / ℃ 80 82 85 88 90 Heating temperature / ℃ 100 105 110 115 120

[0046] Example 6

[0047] The difference between this embodiment and embodiment 5 is that the regeneration agent further comprises a silane coupling agent, the silane coupling agent is KH550, and the amount of the silane coupling agent is 4.3% of the weight of the oil.

[0048] Example 7

[0049] The difference between this embodiment and embodiment 6 is that the amount of silane coupling agent used is 4.5% of the weight of the oil.

[0050] Example 8

[0051] The difference between this embodiment and embodiment 6 is that the amount of silane coupling agent used is 4.6% of the weight of the oil.

[0052] As shown in Table 2, the difference between Examples 8-12 is that the specific surface areas of diatomaceous earth are different.

[0053] Table 2 Specific surface area of ​​diatomite

[0054] sample <![CDATA[Specific surface area of diatomaceous earth m 2 / g]]> Example 8 25 Example 9 35 Example 10 45 Embodiment 11 55 Example 12 65

[0055] Example 13

[0056] The difference between this embodiment and embodiment 12 is that the regeneration agent also includes carbon black, the amount of carbon black is 47% of the weight of the oil, the average particle size of the carbon black is 280nm, and the specific surface area is 8.5m 2 / g.

[0057] Embodiment 14

[0058] The difference between this embodiment and embodiment 13 is that the amount of carbon black used is 58% of the weight of the oil.

[0059] Embodiment 15

[0060] The difference between this embodiment and embodiment 13 is that the amount of carbon black used is 70% of the weight of the oil.

[0061] Example 16

[0062] The difference between this embodiment and embodiment 15 is that the components of the regeneration agent also include aluminum hydroxide, the amount of aluminum hydroxide used is 32% of the weight of the oil, and the average particle size of the aluminum hydroxide is 3 μm.

[0063] As shown in Table 3, the difference between Examples 16-20 is that the percentage of aluminum hydroxide used in the weight of the oil (abbreviated as aluminum hydroxide percentage) is different.

[0064] Table 3 Aluminum hydroxide proportion

[0065] sample Aluminum hydroxide proportion / % Example 16 32 Embodiment 17 40 Embodiment 18 48 Embodiment 19 55 Embodiment 20 63

[0066] Embodiment 21

[0067] The difference between this embodiment and embodiment 20 is that the regeneration agent further comprises wollastonite fiber, and the amount of wollastonite fiber is 13% of the weight of the oil (referred to as fiber ratio). The wollastonite fiber complies with the first-class regulations of "JCT 535-2007 Wollastonite", and the aspect ratio of the wollastonite fiber is 15:1.

[0068] Table 4 Fiber ratio

[0069] sample Fiber ratio / % Embodiment 21 13 Embodiment 22 14 Embodiment 23 15 Embodiment 24 17 Embodiment 25 20

[0070] Comparative Example

[0071] Comparative Example 1

[0072] A regeneration agent for hot-regeneration of asphalt in situ, comprising the following components: 35 kg of furfural extracted oil, 35 kg of waste cooking oil, 24 kg of epoxy fatty acid methyl ester (CAS: 6084-76-0), 5 kg of distilled tall oil (XP708 refined tall oil), and 1 kg of methyl silicone oil (201 methyl silicone oil). The waste cooking oil is the frying oil for fried food, the fresh crude oil corresponding to the waste cooking oil is edible soybean oil, and the density of the waste cooking oil (20°C) is 0.935 g / cm 3 , the dynamic viscosity is 0.175Pa·s; the kinematic viscosity of furfural extracted oil is 5.08mm 2 / s, density (20℃) is 0.922g / cm 3 .

[0073] Comparative Example 2

[0074] The difference between this comparative example and comparative example 1 is that the components of the regeneration agent also include a plasticizer, the plasticizer is dimethyl phthalate, and the weight ratio of the plasticizer to the remaining components is 3.3:68.5.

[0075] Comparative Example 3

[0076] The difference between this comparative example and Example 1 is that the components of the regeneration agent do not include styrene-butadiene latex and diatomaceous earth.

[0077] Comparative Example 4

[0078] The difference between this comparative example and Example 1 is that the components of the regeneration agent do not include diatomaceous earth.

[0079] Comparative Example 5

[0080] The difference between this comparative example and Example 1 is that the components of the regenerating agent do not include styrene-butadiene latex.

[0081] Performance testing methods

[0082] Aged asphalt acquisition: 70# road asphalt was used as the base asphalt, and the asphalt was subjected to accelerated aging for 20 hours in accordance with the "T 0630-2011 Accelerated Asphalt Aging Test in Pressure Aging Vessel" in the "JTG E20-2011 Test Procedure for Highway Engineering Asphalt and Asphalt Mixture" to obtain the aged asphalt.

[0083] Preparation of hot regenerated asphalt: preheat the aged asphalt to 150°C, preheat the regeneration agent to 100°C, then mix the regeneration agent with the aged asphalt, and stir at 1000r / min for 30min at 150°C, then stop heating and stir at 200r / min for 5min to eliminate bubbles, and obtain hot regenerated asphalt. The amount of the regeneration agent and the aged asphalt is determined according to the following principle: the weight of the oil in the regeneration agent is 6% of the total weight of the aged asphalt (the regeneration agent of Comparative Example 1 is regarded as having an oil content of 100%).

[0084] Test method:

[0085] Referring to the record of "SH-T 0777-2005 Asphalt Rheological Property Determination Method (DSR Method)", the rutting factor of hot regenerated asphalt at 76°C was detected, and then the rutting factor measured in Comparative Example 1 was used as a benchmark to calculate the ratio between the rutting factors of each embodiment and comparative example and the rutting factor of Comparative Example 1. The ratio was recorded as the relative rutting factor. The results are shown in Table 5.

[0086] Table 5

[0087] sample Relative rutting factor / % sample Relative rutting factor / % Example 1 115.4 Example 16 124.1 Example 2 116.5 Embodiment 17 124.4 Example 3 116.7 Embodiment 18 125.3 Example 4 116.7 Embodiment 19 125.9 Example 5 116.8 Embodiment 20 126.5 Example 6 119.0 Embodiment 21 127.7 Example 7 119.2 Embodiment 22 128.2 Example 8 119.3 Embodiment 23 128.8 Example 9 119.7 Embodiment 24 129.4 Example 10 120.2 Embodiment 25 130.6 Embodiment 11 120.5 Comparative Example 1 100.0 Example 12 121.4 Comparative Example 2 93.6 Embodiment 13 122.5 Comparative Example 3 94.1 Embodiment 14 122.8 Comparative Example 4 103.8 Embodiment 15 123.1 Comparative Example 5 107.9

[0088] Combining Examples 1-5 and Comparative Examples 1-3 and Table 5, it can be seen that the rutting factors measured in Examples 1-5 are higher than those in Comparative Examples 1-3, while the rutting factors in Comparative Examples 2 and 3 are lower than those in Comparative Example 1, indicating that the use of oil and plasticizer together will affect the anti-rutting performance of hot-regenerated asphalt. However, the present application overcomes the negative impact of oil and plasticizer on the anti-rutting performance by adding styrene-butadiene latex and diatomaceous earth, and obtains hot-regenerated asphalt with good anti-rutting performance.

[0089] It can be seen from Example 1 and Comparative Examples 4-5 and Table 5 that when styrene-butadiene latex and diatomaceous earth are not used in combination, the anti-rutting performance of the thermally regenerated asphalt is difficult to be fully improved.

[0090] Combining Example 5 and Examples 6-8 and Table 5, it can be seen that the rutting factors measured in Examples 6-8 are larger than that in Example 5, indicating that on the basis of Example 5, the addition of silane coupling agent helps to further improve the anti-rutting performance of hot-regenerated asphalt.

[0091] Combining Examples 8-12 with Example 5 and Table 5, it can be seen that when a silane coupling agent is added, the specific surface area of ​​the 2 / g range of diatomaceous earth can improve the anti-rutting performance of hot recycled asphalt, and when the specific surface area of ​​diatomaceous earth is 45-65m 2 / g, this effect is more significant.

[0092] It can be seen from Example 12, Examples 13-15 and Table 5 that, within the scope defined in the present application, the addition of carbon black helps to improve the anti-rutting performance of thermally regenerated asphalt.

[0093] It can be seen from Example 15, Examples 16-20 and Table 5 that within the range defined in the present application, the addition of aluminum hydroxide helps to improve the anti-rutting performance of hot-regenerated asphalt, and this effect is more significant when the amount of aluminum hydroxide is 48-63% of the weight of the oil.

[0094] It can be seen from Example 20, Examples 21-25 and Table 5 that within the range defined in the present application, the addition of wollastonite fiber helps to improve the anti-rutting performance of hot-regenerated asphalt, and this effect is more significant when the amount of wollastonite fiber is 15-20% of the weight of the oil.

[0095] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make modifications to the embodiments of the present application as needed without any creative contribution. However, as long as they are within the scope of the claims of the present application, they are protected by the patent law.

Claims

1. A regeneration agent for hot regeneration of asphalt pavement, characterized in that: The invention comprises the following components in parts by weight: 68.5-76.5 parts of oil, 17.6-22.8 parts of styrene-butadiene latex, 3.3-3.5 parts of plasticizer, and 72-90 parts of diatomaceous earth; the oil comprises furfural extracted oil and waste edible oil, the weight of the furfural extracted oil accounts for 40-44% of the total weight of the oil, and the plasticizer comprises dimethyl phthalate; the components of the regeneration agent also comprise a silane coupling agent, the dosage of the silane coupling agent is 4.3-4.6% of the weight of the oil; the components of the regeneration agent also comprise carbon black, the dosage of the carbon black is 47-70% of the weight of the oil; the components of the regeneration agent also comprise aluminum hydroxide, the dosage of the aluminum hydroxide is 32-63% of the weight of the oil; the components of the regeneration agent also comprise wollastonite fiber, the dosage of the wollastonite fiber is 13-22% of the weight of the oil.

2. The regeneration agent for hot regeneration of asphalt pavement according to claim 1, characterized in that: The specific surface area of ​​the diatomaceous earth is 25-65m 2 / g.

3. The regeneration agent for hot regeneration of asphalt pavement according to claim 2, characterized in that: The specific surface area of ​​the diatomaceous earth is 45-65m 2 / g.

4. The regeneration agent for hot regeneration of asphalt pavement according to claim 1, characterized in that: The amount of aluminum hydroxide used is 48-63% of the weight of the oil.

5. The regeneration agent for hot regeneration of asphalt pavement according to claim 1, characterized in that: The amount of the wollastonite fiber used is 15-20% of the weight of the oil.

6. The method for preparing a regeneration agent for hot regeneration of an asphalt pavement according to any one of claims 1 to 5, characterized in that: The following steps are involved: (1) Heat the oil to 80-90℃ and set aside; (2) adding other components except the oil to the oil, and obtaining a mixture after heat preservation and stirring; (3) The mixture is heated to 100-120°C and stirred to obtain a regeneration agent for hot regeneration of asphalt pavement.