Asphalt recycling agent, modified recycled asphalt mixture, preparation method and application

Abstract

The invention relates to the technical field of old asphalt regeneration, in particular to an asphalt regenerant, a modified regenerated asphalt mixture, a preparation method and application. The asphalt regenerant is prepared from vacuum line oil, a plasticizer, a surfactant, methyl long-carbon-chain alkyl silicone oil, liquid EVA (ethylene vinyl acetate), emulsion styrene-butadiene rubber, liquid petroleum resin, LLDPE (linear low density polyethylene), MXenes and a microcapsule stabilizer, wherein the microcapsule stabilizer is prepared from ethylene bis stearamide, sulfur and N-phenyl-N-cyclohexyl p-phenylenediamine. The modified recycled asphalt mixture is prepared from a milling material, an asphalt recycling agent, SBS modified asphalt, a new aggregate and mineral powder. The prepared asphalt regenerant can improve the mixing amount of a milling material in a regenerated asphalt mixture and improve the use performance of the regenerated asphalt mixture, is beneficial to waste asphalt recovery, improves the resource utilization rate and reduces the construction cost of an asphalt pavement.

Description

Technical Field

[0001] The invention relates to the technical field of waste asphalt regeneration, and in particular to an asphalt regeneration agent, a modified regenerated asphalt mixture, a preparation method and an application thereof. Background Art

[0002] By the end of 2023, the total mileage of my country's comprehensive transportation network will exceed 6 million kilometers, and the total mileage of national highways will be 5.441 million kilometers, including 184,000 kilometers of expressways. The annual maintenance mileage of highways increases year by year, generating a large amount of waste milling materials (RAP), also known as recycled asphalt pavement materials. In terms of national policy, the policy points out that it is necessary to "promote the resource utilization of waste pavements, asphalt and other materials", and requires that by 2025, the recycling rate of asphalt pavement materials for expressways and ordinary national and provincial roads will reach 95% and 80% respectively. In terms of the current status of the industry, the stock of pavement milling materials is large and the utilization rate is low; mining resources are in short supply, and the price of sand and gravel aggregates is high, so the efficient resource utilization of RAP is imminent. Therefore, the research on recycled asphalt mixture (Reclaimed Asphalt Pavement) has become one of the hot spots. Reclaimed asphalt mixture refers to the mixture of old asphalt pavement that has been dug, recycled, crushed, and screened (i.e., waste milling materials) and remixed with asphalt regeneration agent, new asphalt materials, new aggregates, etc. in a certain proportion. Asphalt regeneration agent is also called asphalt concrete regeneration agent, which is a material added to old asphalt to restore or partially restore the performance of the period (asphalt concrete regeneration agent CJ-T554-2024), such as improving the penetration and ductility of old asphalt. Commonly used asphalt regeneration agents are mainly paraffin oil, aromatic extracts, tall oil, naphthenic oil, triglycerides and fatty acids (from vegetable oils).

[0003] In recent years, domestic and foreign scholars have conducted a lot of research on the high proportion of RAP in recycled asphalt mixtures, and proposed high-dosage RAP application technology to increase the RAP ratio to more than 40%. However, there are problems such as the content of modifiers in recycled asphalt mixtures cannot be restored and the performance improvement of the mixture is limited. It is impossible to apply high-dosage RAP regeneration technology to the full structural layer of asphalt pavement. CN104893058A provides a green and environmentally friendly asphalt modifier that reuses waste rubber, but it also uses expensive nanosilver, and its use is as a modifier for asphalt, such as improving the softening point of new asphalt or increasing the low-temperature ductility of asphalt, rather than asphalt regeneration of waste milling materials. CN104788970A provides a regeneration agent and mixture for hot-regenerated asphalt, the regeneration agent contains tall oil, methyl silicone oil, epoxy fatty acid methyl ester, etc., and the RAP production ratio can be increased to 70%. CN115385607A provides a regenerated asphalt mixture, using aromatic oil as an asphalt regeneration agent, but it is a new warm mix agent rather than an asphalt regeneration agent or used for hot-regenerated asphalt mixtures in situ. Summary of the invention

[0004] In view of the above problems, the purpose of the present invention is to provide an asphalt regeneration agent, a modified recycled asphalt mixture, and a preparation method and use thereof, so as to achieve the use of a high dosage of RAP material, reduce the comprehensive cost of the recycled asphalt mixture, and maintain or improve the comprehensive road performance of the recycled asphalt mixture. To achieve the above purpose, the technical solution of the present invention is as follows:

[0005] First, the present invention provides an asphalt regeneration agent, which is made of the following materials by mass percentage: 25-40% of line reduction oil, 5-12% of BT plasticizer, 3-10% of BH surfactant, 3-10% of methyl long carbon chain alkyl silicone oil, 5-15% of liquid EVA, 10-18% of emulsion styrene butadiene rubber, 10-16% of liquid petroleum resin, 5-15% of LLDPE, 1-3% of microcapsule stabilizer and 1-3% of Mxenes. The line reduction oil is composed of line reduction oil and line reduction oil in a mass ratio of 3:1; the BT plasticizer is composed of tall oil, pine tar oil and epoxy fatty acid methyl ester in a mass ratio of (2-5): (2-4): (2-4); the BH surfactant is composed of surfactant alkyl glucoside, petroleum sulfonate, alkylbenzene polyoxyethylene ether and fatty acid glyceride in a mass ratio of (1-4): (3-4): (1-2): (2-3). The microcapsule stabilizer is composed of ethylenebisstearamide, sulfur and N-phenyl-N'-cyclohexyl-p-phenylenediamine in a mass ratio of (3-8):(1-6):(1-2).

[0006] Preferably, the mass ratio of ethylene bisstearamide, sulfur and N-phenyl-N`-cyclohexyl-p-phenylenediamine in the microcapsule stabilizer is selected from one of 3:6:1, 8:1:1, 5:3:2 and 6:3:1.

[0007] Preferably, the mass ratio of tall oil, pine tar and epoxy fatty acid methyl ester in the BT plasticizer is selected from one of 5:2:2, 4:3:3, 3:4:3 and 2:4:4.

[0008] Preferably, the mass ratio of the surfactants alkyl glucoside, petroleum sulfonate, alkylbenzene polyoxyethylene ether, and fatty acid glyceride in the BH surfactant is selected from one of 4:3:1:2, 3:3:2:2, 2:4:2:2, and 1:4:2:3.

[0009] Preferably, the aforementioned Mxenes can be selected from one or more of commercially available MXene-Ti3AlC2, MXene-Ti3C2, MXene-Ti2C, etc.

[0010] Preferably, the aforementioned alkyl glucoside can be selected from one or more of dodecyl glucoside, undecyl glucoside or cetearyl glucoside.

[0011] Preferably, the petroleum sulfonate can be selected from one or more of heavy alkylbenzene sulfonate (HABS), heavy aromatic petroleum sulfonate (HAPS) or fatty alcohol polyoxyethylene ether sulfonate (AESO).

[0012] Preferably, the aforementioned alkylbenzene polyoxyethylene ether can be selected from one or more of NP-4, NP-6, NP-9, etc. The aforementioned fatty acid glyceride can be selected from one or more of monoglycerol fatty acid ester, diglycerol fatty acid ester, triglycerol fatty acid ester, etc.

[0013] Secondly, the present invention provides a method for preparing the aforementioned asphalt regeneration agent, comprising the following steps:

[0014] S1: heating the asphalt regeneration agent, BT plasticizer and methyl long carbon chain alkyl silicone oil to 120-130°C, premixing for 35 minutes, and obtaining an asphalt regeneration agent premix;

[0015] S2: Add liquid EVA, emulsion styrene-butadiene rubber, liquid petroleum resin, and LLDPE to the asphalt regeneration agent premix of step S1 in sequence, and shear with a shearing machine for 20 to 60 minutes to obtain an asphalt regeneration agent pre-sheared material;

[0016] S3: The asphalt regeneration agent pre-sheared material of step S2 is transferred to the stirrer, and the microcapsule stabilizer and MXenes are added, and stirred at 600 r / min for 10 to 15 min to obtain the asphalt regeneration agent microcapsule premix;

[0017] S4: Add BH surfactant to the asphalt regeneration agent microcapsule premix of step S3, keep the stirring rate of step S3 unchanged, and stir for 3 to 5 minutes to obtain the asphalt regeneration agent.

[0018] Again, the present invention provides a modified recycled asphalt mixture prepared by the aforementioned asphalt regeneration agent, which is made of the following materials by mass percentage: 40-82% milling material, 0.15-0.5% asphalt modifier, 0.8-2% SBS modified asphalt, 15-50% new aggregate, and 1-2% mineral powder.

[0019] Among them, milling material, SBS modified asphalt, mineral powder, new aggregate, etc. are commonly used materials in this field. For example, the mineral powder can be selected from limestone powder or blast furnace slag, etc.; the new aggregate can be selected from basalt, limestone, etc.

[0020] In addition, the present invention provides a method for preparing the aforementioned modified recycled asphalt mixture, comprising the following steps:

[0021] Z1: The milling material is heated to 160-170°C, the asphalt regeneration agent is sprayed in, and mixed for 25-40 seconds to obtain the old asphalt-regeneration agent mixture;

[0022] Z2: Add the preheated new aggregate and SBS modified asphalt to the old asphalt-regeneration agent mixture in step Z1 in sequence, and then add mineral powder and mix at 100-300r / min.

[0023] Preferably, the preheating temperatures of the new aggregate and SBS modified asphalt in step Z2 are 180-190° C. and 175-180° C. respectively.

[0024] Preferably, in step Z2, the new aggregate is added and mixed for 30 to 50 seconds, the SBS modified asphalt is added and mixed for 30 to 50 seconds, and the mineral powder is added and mixed for 30 to 50 seconds.

[0025] In addition, the present invention provides the use of the above-mentioned asphalt regeneration agent as a recycling and regeneration treatment agent for waste milling materials.

[0026] Beneficial effects of the present invention:

[0027] The asphalt regeneration agent provided by the present invention is used for regenerating waste milling materials, has good regeneration effect, can increase the amount of waste milling materials in the regenerated asphalt mixture by 80%, and the performance of the regenerated asphalt mixture is equivalent to that of the new asphalt mixture.

[0028] Among them: the line reduction oil is mainly composed of alkanes, cycloalkanes, aromatic hydrocarbons, etc., which is used to improve the viscosity and viscosity index of the regeneration agent, supplement the aromatic content in the regeneration agent, improve the stability and stability of the system, as well as the antioxidant and high temperature resistance of the material. BT plasticizer is used to improve the adhesion and cold resistance of the rubber compound, help the dispersion of additives, delay vulcanization, and generate large dynamic heat. BH surfactant is used to change the spatial structure of the old asphalt, reduce the friction between molecules, enhance the flexibility and lubrication performance of the old asphalt, and significantly reduce the surface energy of asphalt. The inducing agent MXenes can enhance the interaction between the asphalt regeneration agent and the old asphalt matrix, promote interface fusion and polymer reaction progress, and improve the mechanical properties and fatigue properties of the old asphalt. Methyl long-chain alkyl silicone oil has a small surface tension, and has a prominent synergistic effect with BH surfactants. It has a strong molecular lubrication function and excellent heat resistance and hydrophobicity. Liquid EVA has permanent flexibility, acid and alkali resistance, UV aging resistance and good miscibility. It can be mixed with most additives and has a certain degree of adhesion. Emulsion styrene butadiene rubber is a copolymer synthesized by 1,3-butadiene and styrene in emulsion according to the free radical reaction mechanism. It is added to the old asphalt to supplement the modifier component, which can significantly improve the high and low temperature performance and anti-aging performance of the asphalt. Liquid petroleum resin has the properties of good fluidity, stable color, anti-aging, chemical corrosion resistance, etc. LLDPE is made by copolymerization of ethylene and a small amount of α-olefins, and has the advantages of good toughness, heat resistance, and cold resistance.

[0029] Among them: the microcapsule stabilizer uses sulfur and N-phenyl-N`-cyclohexyl p-phenylenediamine as the core material and high-melting-point ethylene bisstearamide as the wall material. With the help of the high melting point of ethylene bisstearamide, in the first stage of preparation, the microcapsule stabilizer is only physically blended with additives such as line oil and resin, and no cross-linking reaction occurs, which ensures the good fluidity of the regeneration agent; and when the regeneration agent is mixed with the recycled material, the temperature exceeds the melting point of the wall material, and the microcapsule stabilizer reaches the second-order release stage, cross-linking reaction occurs with resin, asphalt, etc., and plays a second-order modification role, supplementing the missing light components and modifier components in the old asphalt. Through the two-stage action of the microcapsule stabilizer, the compatibility defects in material mixing are overcome, so that the material advantages can be fully utilized. DETAILED DESCRIPTION

[0030] The technical solution of the present invention is described clearly and completely below in conjunction with specific embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] The raw materials used in the following examples are all commercially available products, for example, methyl long carbon chain alkyl silicone oil can select commercially available VM-12 methyl long carbon chain alkyl silicone oil. Mxenes can select one or more of commercially available MXene-Ti3AlC2, MXene-Ti3C2, MXene-Ti2C, etc. Alkyl glucoside can select one or more of commercially available dodecyl glucoside, undecyl glucoside or cetearyl glucoside, etc. Petroleum sulfonate can select one or more of commercially available heavy alkyl benzene sulfonate (HABS), heavy aromatic petroleum sulfonate (HAPS) or fatty alcohol polyoxyethylene ether sulfonate (AESO), etc. Alkylbenzene polyoxyethylene ether can select one or more of commercially available NP-4, NP-6, NP-9, etc. Fatty acid glyceride can select one or more of commercially available monoglycerol fatty acid ester, diglycerol fatty acid ester, triglycerol fatty acid ester, etc.

[0032] Unless otherwise specified, the mineral powder used in the following examples is limestone mineral powder, and the new aggregate is basalt. Unless otherwise specified, the sources, compositions and qualities of the same materials in the following different examples are consistent.

[0033] Example 1: An asphalt regeneration agent and modified regenerated asphalt mixture

[0034] The asphalt regeneration agent is made of the following materials: 28wt.% of asphalt oil, 10wt.% of BT plasticizer, 8wt.% of BH surfactant, 8wt.% of methyl long-chain alkyl silicone oil (VM-12 methyl long-chain alkyl silicone oil), 6wt.% of liquid polyvinyl acetate (EVA), 14wt.% of emulsion styrene-butadiene rubber, 10wt.% of liquid petroleum resin, 12wt.% of linear low-density polyethylene (LLDPE), 2wt.% of microcapsule stabilizer and 2wt.% of inducing agent Mxenes (MXene-Ti3AlC2). The reduction oil is a mixture of reduction line oil and reduction line oil in a mass ratio of 3:1; the BT plasticizer is a mixture of tall oil, pine tar oil, and epoxy fatty acid methyl ester in a mass ratio of 5:2:2; the BH surfactant is a mixture of non-ionic surfactant alkyl glucoside (dodecyl glucoside), petroleum sulfonate (HABS), alkylbenzene polyoxyethylene ether (NP-6), and fatty acid glyceride (monoglycerol fatty acid ester) in a mass ratio of 4:3:1:2. The microcapsule stabilizer is a mixture of sulfur, N-phenyl-N`-cyclohexyl p-phenylenediamine, and ethylene bisstearamide. Sulfur and N-phenyl-N`-cyclohexyl p-phenylenediamine are used as microcapsule core materials, and the mass ratio of the two is 3:1; ethylene bisstearamide is used as the wall material of the microcapsule, and the mass ratio of the wall material to the capsule core material is 6:4. That is, the mass ratio of ethylene bisstearamide to sulfur and N-phenyl-N`-cyclohexyl p-phenylenediamine is 6:3:1.

[0035] The preparation method of asphalt regeneration agent is as follows:

[0036] 1): Heat the asphalt regeneration agent, BT plasticizer and methyl long carbon chain alkyl silicone oil to 120°C, put them in a mixer and premix for 5 minutes to obtain an asphalt regeneration agent premix;

[0037] 2) Add liquid EVA, emulsion styrene-butadiene rubber, liquid petroleum resin and LLDPE to the asphalt regeneration agent premix of step 1) in sequence, and shear for 30 minutes to make the LLDPE particles dispersed evenly to obtain the asphalt regeneration agent premix;

[0038] 3): The asphalt regeneration agent pre-sheared material of step 2) is transferred to the stirrer, and the microcapsule stabilizer and the inducing agent MXenes are added. The stirring rate is 600r / min and the stirring time is 15min to obtain the asphalt regeneration agent microcapsule premix.

[0039] 4): Add BH surfactant to the asphalt regeneration agent microcapsule premix of step 3), keep the stirring rate of step 3) unchanged, and stir for 5 minutes to obtain the asphalt regeneration agent.

[0040] Ingredients of modified recycled asphalt mixture (gradation type is AC-20): the amount of milling material is 50wt.%, the amount of asphalt regeneration agent is 0.18wt.%, the amount of SBS modified asphalt is 1.87wt.%, the amount of new aggregate is 45.95wt.%, and the amount of mineral powder is 2wt.%.

[0041] Preparation of modified recycled asphalt mixture: The milled material is heated to 160°C by microwave equipment, and the asphalt regeneration agent in step 4) is sprayed in, mixed for 28 seconds, new aggregate is added and mixed for 50 seconds, and then SBS modified asphalt is added and mixed for 50 seconds, and finally mineral powder is added and mixed for 50 seconds, and the mixing speed is 100r / min to obtain modified recycled asphalt mixture. The new aggregate is preheated to 190°C before adding, and the SBS modified asphalt is preheated to 180°C before adding, and the mixing temperature is controlled at 160°C to 190°C.

[0042] Example 2: An asphalt regeneration agent and modified regenerated asphalt mixture

[0043] The asphalt regeneration agent is made of the following materials: 31wt.% of line reduction oil, 9wt.% of BT plasticizer, 7wt.% of BH surfactant, 6wt.% of methyl long carbon chain alkyl silicone oil (VM-12 methyl long carbon chain alkyl silicone oil), 12wt.% of liquid EVA, 12wt.% of emulsion styrene butadiene rubber, 12wt.% of liquid petroleum resin, 8wt.% of LLDPE, 2wt.% of microcapsule stabilizer and 1wt.% of inducing agent MXenes (MXene-Ti3C2). The line reduction oil is a mixture of line reduction oil and line reduction oil in a mass ratio of 3:1; the BT plasticizer is a mixture of tall oil, pine tar oil and epoxy fatty acid methyl ester in a mass ratio of 5:2:2; the BH surfactant is a mixture of non-ionic surfactant alkyl glucoside (undecyl glucoside), petroleum sulfonate (HAPS), alkylbenzene polyoxyethylene ether (NP-4) and fatty acid glyceride (triglycerol fatty acid ester) in a mass ratio of 4:3:1:2. The microcapsule stabilizer is a mixture of sulfur, N-phenyl-N`-cyclohexyl-p-phenylenediamine and ethylene bisstearamide. Sulfur and N-phenyl-N`-cyclohexyl-p-phenylenediamine are used as microcapsule core materials, and the mass ratio of the two is 3:2; ethylene bisstearamide is used as microcapsule wall material, and the mass ratio of the wall material to the core material is 5:5. That is, the mass ratio of ethylene bisstearamide to sulfur and N-phenyl-N`-cyclohexyl-p-phenylenediamine is 5:3:2.

[0044] The preparation method of asphalt regeneration agent is as follows:

[0045] 1): Heat the asphalt regeneration agent, BT plasticizer and methyl long carbon chain alkyl silicone oil to 130°C, put them in a mixer and premix for 3 minutes to obtain an asphalt regeneration agent premix;

[0046] 2) Add liquid EVA, emulsion styrene-butadiene rubber, liquid petroleum resin and LLDPE to the asphalt regeneration agent premix of step 1) in sequence, and shear for 50 minutes to make the LLDPE particles dispersed evenly to obtain the asphalt regeneration agent premix;

[0047] 3): The asphalt regeneration agent pre-sheared material of step 2) is transferred to the stirrer, and the microcapsule stabilizer and the inducing agent MXenes are added. The stirring rate is 600r / min and the stirring time is 10min to obtain the asphalt regeneration agent microcapsule premix.

[0048] 4): Add BH surfactant to the asphalt regeneration agent microcapsule premix of step 3), keep the stirring rate of step 3) unchanged, and stir for 3 minutes to obtain the asphalt regeneration agent.

[0049] Ingredients of modified recycled asphalt mixture (gradation type is AC-20): the amount of milling material is 60wt.%, the amount of asphalt regeneration agent is 0.22wt.%, the amount of SBS modified asphalt is 1.38wt.%, the amount of new aggregate is 36.4wt.%, and the amount of mineral powder is 2wt.%.

[0050] Preparation of modified recycled asphalt mixture: The milled material is heated to 170°C by microwave equipment, and the asphalt regeneration agent in step 4) is sprayed in, mixed for 30 seconds, new aggregate is added and mixed for 50 seconds, and then SBS modified asphalt is added and mixed for 50 seconds, and finally mineral powder is added and mixed for 50 seconds, and the mixing speed is 100r / min to obtain modified recycled asphalt mixture. The new aggregate is preheated to 180°C before adding, and the SBS modified asphalt is preheated to 175°C before adding, and the mixing temperature is controlled at 170°C to 180°C.

[0051] Example 3: An asphalt regeneration agent and modified regenerated asphalt mixture

[0052] The asphalt regeneration agent is made of the following materials: 34wt.% of line reduction oil, 7wt.% of BT plasticizer, 5wt.% of BH surfactant, 4wt.% of methyl long carbon chain alkyl silicone oil (VM-12 methyl long carbon chain alkyl silicone oil), 10wt.% of liquid EVA, 16wt.% of emulsion styrene butadiene rubber, 14wt.% of liquid petroleum resin, 6wt.% of LLDPE, 1wt.% of microcapsule stabilizer and 3wt.% of inducing agent MXenes (MXene-Ti2C). The line reduction oil is a mixture of line reduction oil and line reduction oil in a mass ratio of 3:1; the BT plasticizer is a mixture of tall oil, pine tar oil and epoxy fatty acid methyl ester in a mass ratio of 5:2:2; the BH surfactant is a mixture of non-ionic surfactant alkyl glucoside (cetyl stearyl glucoside), petroleum sulfonate (AESO), alkylbenzene polyoxyethylene ether (NP-6) and fatty acid glyceride (diglycerol fatty acid ester) in a mass ratio of 4:3:1:2. The microcapsule stabilizer is a mixture of sulfur, N-phenyl-N`-cyclohexyl-p-phenylenediamine and ethylene bisstearamide. Sulfur and N-phenyl-N`-cyclohexyl-p-phenylenediamine are used as microcapsule core materials, and the mass ratio of the two is 1:1; ethylene bisstearamide is used as microcapsule wall material, and the mass ratio of the wall material to the core material is 8:2. That is, the mass ratio of ethylene bisstearamide to sulfur and N-phenyl-N`-cyclohexyl-p-phenylenediamine is 8:1:1.

[0053] The preparation method of asphalt regeneration agent is as follows:

[0054] 1): Heat the asphalt regeneration agent, BT plasticizer and methyl long carbon chain alkyl silicone oil to 120°C, put them in a mixer and premix for 4 minutes to obtain an asphalt regeneration agent premix;

[0055] 2) Add liquid EVA, emulsion styrene-butadiene rubber, liquid petroleum resin and LLDPE to the asphalt regeneration agent premix of step 1) in sequence, and shear for 60 minutes to make the LLDPE particles dispersed evenly to obtain the asphalt regeneration agent premix;

[0056] 3): The asphalt regeneration agent pre-sheared material of step 2) is transferred to the stirrer, and the microcapsule stabilizer and inducing agent MXenes are added. The stirring rate is 600r / min and the stirring time is 12min to obtain the asphalt regeneration agent microcapsule premix.

[0057] 4): Add BH surfactant to the asphalt regeneration agent microcapsule premix of step 3), keep the stirring rate of step 3) unchanged, and stir for 4 minutes to obtain the asphalt regeneration agent.

[0058] Ingredients of modified recycled asphalt mixture (gradation type is AC-20): the amount of milling material is 70wt.%, the amount of asphalt regeneration agent is 0.25wt.%, the amount of SBS modified asphalt is 0.9wt.%, the amount of new aggregate is 26.85wt.%, and the amount of mineral powder is 2wt.%.

[0059] Preparation of modified recycled asphalt mixture: The milled material is heated to 170°C by microwave equipment, and the asphalt regeneration agent in step 4) is sprayed in, mixed for 35 seconds, new aggregate is added and mixed for 45 seconds, and then SBS modified asphalt is added and mixed for 45 seconds, and finally mineral powder is added and mixed for 45 seconds, and the mixing speed is 300r / min to obtain modified recycled asphalt mixture. The new aggregate is preheated to 185°C before adding, and the SBS modified asphalt is preheated to 175°C before adding, and the mixing temperature is controlled at 170°C to 185°C.

[0060] Example 4: An asphalt regeneration agent and modified regenerated asphalt mixture

[0061] The asphalt regeneration agent is made of the following materials: 38wt.% of line reduction oil, 6wt.% of BT plasticizer, 4wt.% of BH surfactant, 4wt.% of methyl long carbon chain alkyl silicone oil (VM-12 methyl long carbon chain alkyl silicone oil), 8wt.% of liquid EVA, 12wt.% of emulsion styrene butadiene rubber, 10wt.% of liquid petroleum resin, 14wt.% of LLDPE, 3wt.% of microcapsule stabilizer and 1wt.% of inducing agent Mxenes (MXene-Ti3AlC2). The line reduction oil is a mixture of line reduction oil and line reduction oil in a mass ratio of 3:1; the BT plasticizer is a mixture of tall oil, pine tar oil and epoxy fatty acid methyl ester in a mass ratio of 5:2:2; the BH surfactant is a mixture of non-ionic surfactant alkyl glucoside (cetyl stearyl glucoside), petroleum sulfonate (AESO), alkylbenzene polyoxyethylene ether (NP-9) and fatty acid glyceride (diglycerol fatty acid ester) in a mass ratio of 4:3:1:2. The microcapsule stabilizer is a mixture of sulfur, N-phenyl-N`-cyclohexyl-p-phenylenediamine and ethylene bisstearamide. Sulfur and N-phenyl-N`-cyclohexyl-p-phenylenediamine are used as microcapsule core materials, and the mass ratio of the two is 3:0.5; ethylene bisstearamide is used as microcapsule wall material, and the mass ratio of the wall material to the core material is 3:7. That is, the mass ratio of ethylene bisstearamide to sulfur and N-phenyl-N`-cyclohexyl-p-phenylenediamine is 3:6:1.

[0062] The preparation method of asphalt regeneration agent is as follows:

[0063] 1): Heat the asphalt regeneration agent, BT plasticizer and methyl long carbon chain alkyl silicone oil to 130°C, put them in a mixer and premix for 5 minutes to obtain an asphalt regeneration agent premix;

[0064] 2) Add liquid EVA, emulsion styrene-butadiene rubber, liquid petroleum resin and LLDPE to the asphalt regeneration agent premix of step 1) in sequence, and shear for 20 minutes to make the LLDPE particles dispersed evenly to obtain the asphalt regeneration agent premix;

[0065] 3): The asphalt regeneration agent pre-sheared material of step 2) is transferred to the stirrer, and the microcapsule stabilizer and the inducing agent MXenes are added. The stirring rate is 600r / min and the stirring time is 10min to obtain the asphalt regeneration agent microcapsule premix.

[0066] 4): Add BH surfactant to the asphalt regeneration agent microcapsule premix of step 3), keep the stirring rate of step 3) unchanged, and stir for 3 minutes to obtain the asphalt regeneration agent.

[0067] Ingredients of modified recycled asphalt mixture (gradation type is AC-20): the amount of milling material is 80wt.%, the amount of asphalt regeneration agent is 0.3wt.%, the amount of SBS modified asphalt is 0.9wt.%, the amount of new aggregate is 16.8wt.%, and the amount of mineral powder is 2wt.%.

[0068] Preparation of modified recycled asphalt mixture: The milled material is heated to 165°C by microwave equipment, and the asphalt regeneration agent in step 4) is sprayed in, mixed for 40s, new aggregate is added and mixed for 40s, then SBS modified asphalt is added and mixed for 40s, and finally mineral powder is added and mixed for 40s, and the mixing speed is 200r / min to obtain modified recycled asphalt mixture. The new aggregate is preheated to 185°C before adding, and the SBS modified asphalt is preheated to 180°C before adding, and the mixing temperature is controlled at 165°C to 185°C.

[0069] Example 5: An asphalt regeneration agent and modified regenerated asphalt mixture

[0070] The difference from Example 2 is that the mass ratio of tall oil, pine tar, and epoxy fatty acid methyl ester in the BT plasticizer is 4:3:3; the mass ratio of nonionic surfactant alkyl glucoside, petroleum sulfonate, alkylbenzene polyoxyethylene ether, and fatty acid glyceride in the BH surfactant is 3:3:2:2. Others are the same as Example 2.

[0071] Example 6: An asphalt regeneration agent and modified regenerated asphalt mixture

[0072] The difference from Example 2 is that the mass ratio of tall oil, pine tar, and epoxy fatty acid methyl ester in the BT plasticizer is 3:4:3; the mass ratio of nonionic surfactant alkyl glucoside, petroleum sulfonate, alkylbenzene polyoxyethylene ether, and fatty acid glyceride in the BH surfactant is 2:4:2:2. Others are the same as in Example 2.

[0073] Example 7: Asphalt regeneration agent and modified regenerated asphalt mixture

[0074] The difference from Example 2 is that the mass ratio of tall oil, pine tar, and epoxy fatty acid methyl ester in the BT plasticizer is 2:4:4; the mass ratio of nonionic surfactant alkyl glucoside, petroleum sulfonate, alkylbenzene polyoxyethylene ether, and fatty acid glyceride in the BH surfactant is 1:4:2:3. Others are the same as Example 2.

[0075] Comparative Example 1: A modified recycled asphalt mixture

[0076] The difference from Example 4 is that the asphalt regeneration agent is replaced by the commercially available RA-1 type regeneration agent with the same dosage.

[0077] Comparative Example 2: An asphalt regeneration agent and a modified regenerated asphalt mixture

[0078] The difference from Example 4 is that the asphalt regeneration agent of Example A1 of patent CN104788970A is used in the same dosage and is prepared according to the preparation process of Example A1 (the dosage of the asphalt regeneration agent is the same as that of Example 4).

[0079] Comparative Example 3: An asphalt regeneration agent and a modified regenerated asphalt mixture

[0080] The difference from Example 4 is that the microcapsule stabilizer is a mixture of sulfur, N-phenyl-N`-cyclohexyl-p-phenylenediamine, and low melting point wax (No. 48 low melting point paraffin); sulfur and N-phenyl-N`-cyclohexyl-p-phenylenediamine are used as microcapsule core materials, and the mass ratio of the two is 3:1; the low melting point wax is used as the wall material of the microcapsule, and the mass ratio of the wall material to the core material is 5:5.

[0081] Comparative Example 4: An asphalt regeneration agent and a modified regenerated asphalt mixture

[0082] The difference from Example 4 is that: in step 3), no microcapsule stabilizer is added (that is, the asphalt regeneration agent does not contain the microcapsule stabilizer), but when the modified recycled asphalt mixture is prepared, the milling material is heated to 165°C by a microwave device, and the asphalt regeneration agent and the microcapsule stabilizer are sprayed in (that is, the microcapsule stabilizer is added when the milling material is heated to 165°C).

[0083] The recycled modified asphalt is prepared according to the industry standard "Asphalt Concrete Regeneration Agent" (CJ-T554-2024) issued by the Ministry of Housing and Urban-Rural Development, and the asphalt regeneration agent dosage is 5%.

[0084] The properties of recycled modified asphalt and modified recycled asphalt mixture were measured according to the conventional method "Testing Procedures for Asphalt and Asphalt Mixtures in Highway Engineering" JTG E20-2011. The results are shown in Table 1.

[0085] Table 1 Test results of performance indexes of recycled modified asphalt and its modified recycled asphalt mixture

[0086]

[0087]

[0088] Note: Asphalt recovery was performed using a rotary evaporator method, and the Hamburg rutting test was performed using a 60°C water bath.

[0089] Analysis of the above test results shows that the indicators of the recycled modified asphalt and modified recycled asphalt mixture prepared by the method of the present invention meet the use standards, and the indicators such as 5°C elongation, dynamic stability, low-temperature failure strain, residual strength ratio, number of wheel rollings, and wheel track depth exceed those of the comparative examples.

[0090] The asphalt regeneration agent of the present invention has the advantages of low addition and allows a high addition amount of milling material (i.e., waste milling material, RAP), which is conducive to improving the recycling rate of old materials. This is related to the fact that the wall material and the capsule core material form a core-shell structure, avoiding premature cross-linking of the asphalt regeneration agent, thereby ensuring that the asphalt regeneration agent has excellent permeability and modified regeneration effect at the same time.

[0091] It is obvious to those skilled in the art that the present invention is not limited to the above exemplary embodiments. Moreover, the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention. In addition, it should be understood that although this specification is described in accordance with the implementation modes, not every implementation mode can represent only an independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should take the specification as a whole. The technical solutions in the various embodiments can also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. An asphalt regeneration agent, characterized in that: It is made of the following materials by mass percentage: 25-40% of wire drawing oil, 5-12% of BT plasticizer, 3-10% of BH surfactant, 3-10% of methyl long-chain alkyl silicone oil, 5-15% of liquid EVA, 10-18% of emulsion styrene-butadiene rubber, 10-16% of liquid petroleum resin, 5-15% of LLDPE, 1-3% of microcapsule stabilizer and 1-3% of Mxenes. The debonding oil is composed of debonding three-line oil and debonding four-line oil in a mass ratio of 3:1; the BT plasticizer is composed of tall oil, pine tar oil, and epoxy fatty acid methyl ester in a mass ratio of (2-5): (2-4): (2-4); the BH surfactant is composed of surfactant alkyl glucoside, petroleum sulfonate, alkylbenzene polyoxyethylene ether, and fatty acid glyceride in a mass ratio of (1-4): (3-4): (1-2): (2-3). The microcapsule stabilizer is composed of ethylene bisstearamide, sulfur, and N-phenyl-N'-cyclohexyl p-phenylenediamine in a mass ratio of (3-8): (1-6): (1-2).

2. An asphalt regeneration agent according to claim 1, characterized in that: The mass ratio of ethylenebisstearamide, sulfur and N-phenyl-N`-cyclohexyl-p-phenylenediamine in the microcapsule stabilizer is selected from one of 3:6:1, 8:1:1, 5:3:2 and 6:3:

1.

3. An asphalt regeneration agent according to claim 1, characterized in that: The mass ratio of tall oil, pine tar and epoxy fatty acid methyl ester in the BT plasticizer is selected from one of 5:2:2, 4:3:3, 3:4:3 and 2:4:4; the mass ratio of surfactant alkyl glucoside, petroleum sulfonate, alkylbenzene polyoxyethylene ether and fatty acid glyceride in the BH surfactant is selected from one of 4:3:1:2, 3:3:2:2, 2:4:2:2 and 1:4:2:

3.

4. The asphalt regeneration agent according to claim 1, characterized in that: The Mxenes are selected from one or more of MXene-Ti3AlC2, MXene-Ti3C2, and MXene-Ti2C; the alkyl glucoside is selected from one or more of dodecyl glucoside, undecyl glucoside, or cetearyl glucoside; the petroleum sulfonate is selected from one or more of heavy alkylbenzene sulfonate (HABS), heavy aromatic petroleum sulfonate (HAPS), or fatty alcohol polyoxyethylene ether sulfonate (AESO); the alkylbenzene polyoxyethylene ether is selected from one or more of NP-4, NP-6, and NP-9; the fatty acid glyceride is selected from one or more of monoglycerol fatty acid ester, diglycerol fatty acid ester, and triglycerol fatty acid ester.

5. A method for preparing the asphalt regeneration agent according to claim 1, characterized in that: The steps include: S1: heating the asphalt regeneration agent, BT plasticizer and methyl long carbon chain alkyl silicone oil to 120-130°C and premixing for 35 minutes to obtain an asphalt regeneration agent premix; S2: Add liquid EVA, emulsion styrene-butadiene rubber, liquid petroleum resin, and LLDPE to the asphalt regeneration agent premix of step S1 in sequence, and shear with a shearing machine for 20 to 60 minutes to obtain an asphalt regeneration agent pre-sheared material; S3: The asphalt regeneration agent pre-sheared material of step S2 is transferred to the stirrer, and the microcapsule stabilizer and MXenes are added, and stirred at 600r / min for 10 to 15min to obtain the asphalt regeneration agent microcapsule premix; S4: Add BH surfactant to the asphalt regeneration agent microcapsule premix of step S3, keep the stirring rate of step S3 unchanged, and stir for 3 to 5 minutes to obtain the asphalt regeneration agent.

6. A modified regenerated asphalt mixture prepared by using the asphalt regeneration agent according to claim 1, characterized in that: The modified recycled asphalt mixture is made of the following materials by mass percentage: 40-82% of milling material, 0.15-0.5% of asphalt regeneration agent, 0.8-2% of SBS modified asphalt, 15-50% of new aggregate, and 1-2% of mineral powder.

7. A method for preparing the modified recycled asphalt mixture according to claim 6, characterized in that: The steps include: Z1: The milling material is heated to 160-170℃, the asphalt regeneration agent is sprayed in, and mixed for 25-40s to obtain the old asphalt-regeneration agent mixture; Z2: Add the preheated new aggregate and SBS modified asphalt to the old asphalt-regeneration agent mixture in step Z1 in sequence, and then add mineral powder and mix at 100-300 r / min.

8. The method for preparing the modified regenerated asphalt mixture according to claim 7, characterized in that: In the step Z2, the preheating temperatures of the new aggregate and the SBS modified asphalt are 180-190° C. and 175-180° C. respectively.

9. The method for preparing the modified regenerated asphalt mixture according to claim 7, characterized in that: In the step Z2, the new aggregate is added and mixed for 30 to 50 seconds, the SBS modified asphalt is added and mixed for 30 to 50 seconds, and the mineral powder is added and mixed for 30 to 50 seconds.

10. Use of the asphalt regeneration agent described in any one of claims 1 to 4 or the asphalt regeneration agent prepared in claim 5 as a recycling and regeneration treatment agent for waste milling materials.

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