High-performance low-temperature environment-friendly asphalt and preparation method thereof

Abstract

The invention relates to the field of road engineering materials, in particular to high-performance low-temperature environment-friendly asphalt and a preparation method thereof. The high-performance low-temperature environment-friendly asphalt is prepared from the following components in parts by mass: 25 to 35 parts of recycled waste rubber powder, 8 to 12 parts of steel slag powder, 5 to 8 parts of ardealite, 8 to 12 parts of bio-based low-temperature activating agent, 3 to 6 parts of composite fiber, 1 to 2 parts of efficient dispersing agent and 30 to 65 parts of matrix asphalt. The high-performance low-temperature environment-friendly asphalt provided by the invention innovatively solves the technical problems of existing modified asphalt in the aspects of low-temperature crack resistance, environmental protection, cost control and the like, and has a wide application prospect and a good market prospect.

Description

Technical Field

[0001] This invention relates to the field of road engineering materials, and in particular to a high-performance, low-temperature, environmentally friendly asphalt and its preparation method. Background Technology

[0002] In road construction, the performance and cost of asphalt materials are of paramount importance.

[0003] Traditional asphalt and some modified asphalts have shortcomings in low-temperature performance, which can easily lead to low-temperature cracking of pavements and affect the service life of roads. At the same time, high-performance asphalt modifiers or additives are often expensive, limiting their widespread application. Currently, asphalt products on the market struggle to effectively control costs while ensuring low-temperature performance and meeting environmental requirements, necessitating innovative formulations to balance performance and cost.

[0004] In view of this, the present invention is proposed. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention provides a low-cost, high-performance, low-temperature environmentally friendly asphalt and its preparation method. While ensuring low mixing temperature, low operating temperature, and excellent low-temperature performance, it significantly reduces production costs, possesses good environmental performance, and its overall performance is significantly superior to existing similar products.

[0006] In a first aspect, the present invention provides a high-performance, low-temperature, environmentally friendly asphalt, which comprises the following components in parts by mass: Recycle 25-35 parts of waste rubber powder 8-12 parts of steel slag powder 5-8 parts of phosphogypsum 8-12 parts of bio-based low-temperature activator 3-6 parts of composite fiber 1-2 parts of high-efficiency dispersant 30-65 parts of base asphalt.

[0007] In this invention, the addition of steel slag powder, phosphogypsum, etc., can replace expensive materials and reduce costs. At the same time, through the optimization of the raw material combination and dosage ratio of recycled waste rubber powder, steel slag powder, phosphogypsum, bio-based low-temperature activator, composite fiber, high-efficiency dispersant and matrix asphalt, the active ingredients contained in steel slag powder can react better with matrix asphalt to enhance adhesion and improve pavement strength. Phosphogypsum further fills and strengthens asphalt, improves microstructure, and enhances compactness and high-temperature stability. The recycled waste rubber powder, steel slag powder and phosphogypsum work together to improve the overall performance of asphalt and significantly reduce the occurrence of low-temperature cracking. The interaction between recycled waste rubber powder and other raw materials can increase the flexibility of asphalt, and the interaction with steel slag powder and phosphogypsum can significantly improve low-temperature crack resistance and other properties.

[0008] Preferably, the mass ratio of the recycled waste rubber powder to the bio-based low-temperature activator is 28~33:8~11. In this invention, the recycled waste rubber powder and the bio-based low-temperature activator work synergistically to further enhance the low-temperature flexibility and stability of the base asphalt formulation system, allowing the working temperature to reach below -20℃, effectively preventing cracking and extending pavement life. Preferably, the mass ratio of the recycled waste rubber powder, bio-based low-temperature activator, and base asphalt is 28~33:8~11:30~45, more preferably 30~32:9~10:37~38.5. In this invention, the overall performance of the asphalt is better when the recycled waste rubber powder, bio-based low-temperature activator, and base asphalt are in the above-mentioned preferred ratios.

[0009] Preferably, the base asphalt is petroleum asphalt or natural asphalt; preferably, the aromatic content of the base asphalt is 20%~30%, and the resin content is 25%~35%; in this invention, the aromatic content of the base asphalt is 20%~30%, and the resin content is 25%~35%; the base asphalt is preferably road petroleum asphalt with a penetration (25℃, 100g, 5s) of 60~80 (0.1mm), preferably No. 70 or No. 90 base asphalt, with a softening point ≥46℃ and ductility (15℃) ≥100cm. The base asphalt used in the system of this invention has good adhesion and plasticity, providing stable basic bonding performance for the composite modified system; by controlling the aromatic content (20%~30%) and resin content (25%~35%) of the base asphalt, the compatibility with recycled waste rubber powder and bio-based low-temperature activators can be optimized, increasing the temperature sensitivity (penetration index PI) of the modified asphalt to -0.5~0.5, and broadening the applicable temperature range.

[0010] Preferably, the recycled waste rubber powder is waste rubber product powder with a particle size of 40-60 mesh. In this invention, the recycled waste rubber powder originates from waste rubber products. With a preferred particle size of 40-60 mesh, it forms an elastic network in asphalt, which, compared to rubber particles of other sizes, further enhances low-temperature flexibility and crack resistance, preventing road surface cracking at low temperatures, realizing the resource utilization of waste, and reducing costs and environmental pollution. For example, 40 mesh, 45 mesh, 50 mesh, 55 mesh, etc., with 40-50 mesh being preferred. When the recycled waste rubber powder originates from waste rubber products and is crushed and screened to a preferred particle size of 40-50 mesh, its elastic rubber particles better form a continuously distributed three-dimensional elastic network structure in the asphalt. Through physical adsorption and swelling, it enhances the flexibility of the asphalt phase, increasing the ductility of the asphalt at -10℃ by more than 40% compared to the base asphalt, significantly improving low-temperature crack resistance. At the same time, the resource utilization of waste rubber products can reduce raw material costs by 20%-25% and reduce solid waste emissions by 30 kg / ton of asphalt, achieving a balance between environmental and economic benefits.

[0011] Preferably, the bio-based low-temperature activator is a fatty acid ester compound. In this invention, the bio-based low-temperature activator is a fatty acid ester compound (preferably a methyl oleate derivative or an ethyl linoleate derivative) prepared from vegetable oils (such as soybean oil or rapeseed oil). The hydroxyl or carboxyl functional groups in its molecular structure can bind to asphalt molecules through hydrogen bonding, lowering the glass transition temperature of asphalt and improving its low-temperature ductility. Preferably, the bio-based low-temperature activator has an acid value of 5-15 mgKOH / g and a saponification value of 150-200 mgKOH / g; more preferably, an acid value of 6-18 mgKOH / g and a saponification value of 170-195 mgKOH / g. In this invention, the use of the bio-based low-temperature activator with the preferred acid value and saponification value allows it to have better compatibility with the base asphalt, facilitating its better modification effect.

[0012] Further preferably, the bio-based low-temperature activator is a fatty acid ester compound prepared from soybean oil or rapeseed oil. In this invention, the bio-based low-temperature activator is extracted from biomass resources such as plant oils (soybean oil or rapeseed oil), activates asphalt molecules at low temperatures, promotes cross-linking reactions, lowers the glass transition temperature, ensures low-temperature performance, reduces dependence on petroleum-based products, and has lower costs. This invention uses a bio-based low-temperature activator to reduce viscosity, which helps lower the mixing temperature to 100-110℃, reduces energy consumption, and its low-cost characteristics reduce the overall cost, facilitating low-temperature construction. The bio-based low-temperature activator is preferably a methyl oleate derivative or an ethyl linoleate derivative, and the methyl oleate derivative is preferably epoxy methyl oleate. The present invention uses renewable vegetable oils such as soybean oil and rapeseed oil as raw materials, and the bio-based low-temperature activator prepared by the two-step transesterification-epoxidation method is preferably an methyl oleate derivative (epoxy methyl oleate). The hydroxyl (-OH) and carboxyl (-COOH) functional groups contained in its molecular structure can form hydrogen bonds with the polar components in asphalt, promote the cross-linking reaction between asphalt molecules, and reduce the glass transition temperature (Tg) of asphalt from -15℃ to below -28℃. Meanwhile, when the mass ratio of recycled waste rubber powder to the bio-based low-temperature activator is 30~32:9~10, the two produce a significant synergistic effect. The elastic network structure provides a physical support framework for the cross-linking reaction, while the polar groups of the bio-based activator enhance the interfacial adhesion between the rubber particles and the asphalt phase, enabling the asphalt to achieve a bending strain of over 4000 με at -20℃ (30% higher than that of asphalt modified with waste rubber powder alone), and the mixing temperature is stable at 105±5℃, which is 30℃ lower than that of traditional SBS modified asphalt, resulting in a 25% reduction in energy consumption costs.

[0013] Preferably, the high-efficiency dispersant is an anionic surfactant. In this invention, a low-cost anionic surfactant is selected to ensure uniform dispersion of each component, stabilize the modification effect, guarantee uniform asphalt performance, and avoid excessive cost increases. Using an optimized high-efficiency dispersant in combination with other components in the formulation can further enhance the stability of asphalt and its mixtures, resulting in a more uniform distribution of each component, while also improving low-temperature properties such as crack resistance under low-temperature conditions. The high-efficiency dispersant is preferably sodium dodecylbenzenesulfonate (SDBS) and / or sodium alkyl sulfate (SDS), more preferably sodium dodecylbenzenesulfonate.

[0014] Preferably, the hydrophilic-lipophilic balance (HLB) value of the high-efficiency dispersant is 10-14, and more preferably 10.5-12. In this invention, the high-efficiency dispersant used can more effectively reduce the interfacial tension between recycled waste rubber powder and matrix asphalt under the preferred HLB value, promote uniform dispersion of the two phases, and avoid agglomeration.

[0015] Preferably, the mass ratio of the bio-based low-temperature activator to the high-efficiency dispersant is 9-10:1-1.5. In this invention, a certain proportion of the bio-based low-temperature activator and the high-efficiency dispersant (SDBS) work synergistically through a "polarity matching-interfacial wetting" mechanism: the former reduces the viscosity of the asphalt phase and activates interfacial activity, while the latter prevents the agglomeration of waste rubber powder particles through electrostatic repulsion, ensuring that the dispersed particle size of waste rubber powder in the asphalt is ≤50μm, and improving the distribution uniformity by 40%, thereby avoiding the risk of cracking caused by local stress concentration, and further increasing the low-temperature splitting strength retention rate of the asphalt mixture from 75% to over 85%. This synergistic system not only endows asphalt with excellent working stability below -20℃ (cracking temperature is 15℃ lower than that of traditional asphalt), but also reduces the proportion of petroleum-based components in the formulation system from 80% to below 60% through biomass raw material substitution and high-value utilization of solid waste, reducing the overall carbon footprint by 18%, becoming an innovative low-temperature asphalt solution that balances performance, cost, and environmental protection.

[0016] Preferably, the steel slag powder has a particle size of 30-80 μm, more preferably 40-60 μm, and its main components are 40%-50% Fe3O4, 20%-25% CaO, and 15%-20% SiO2, with a free CaO content ≤3% and a specific surface area ≥400 m². 2 / kg; In this invention, the steel slag powder in the composition system can undergo physical adsorption with the polar groups of asphalt, enhancing interfacial adhesion. For example, the CaO active sites on its surface undergo chemical adsorption with acidic groups (such as carboxylic acids and phenols) in asphalt, forming a "steel slag powder-asphalt" interfacial bonding layer, which improves the adhesion grade between asphalt and aggregate from level 3 to level 5 (boiling method), significantly enhancing the interlayer adhesion of the pavement structure. When the steel slag powder content is 8-12 parts, the Marshall stability of the asphalt mixture is increased by 15%-20% compared with the base asphalt, and the compressive strength is increased by 25%, effectively replacing high-priced mineral powder and reducing raw material costs by 10%-15%.

[0017] Preferably, the phosphogypsum is made from phosphate fertilizer industrial waste residue after water washing to remove impurities, low-temperature drying, and grinding to a particle size ≤50μm. Its main component is CaSO4·2H2O. In this invention, the phosphogypsum is made from phosphate fertilizer industrial waste residue after water washing to remove impurities (removing free acid and impurity ions), low-temperature drying (moisture content ≤1%), and grinding to a particle size ≤50μm. Its main component is CaSO4·2H2O (purity ≥85%), containing (small amounts) SiO2 and Al2O3 impurities. Its plate-like crystal structure can fill the pores of asphalt mortar, reducing the porosity of the asphalt mixture from 5% to below 3%, increasing the density by 8%, and improving the high-temperature stability (dynamic stability at 60℃) from 2000 cycles / mm to over 4000 cycles / mm. The Ca in the phosphogypsum... 2+ The coordination of ions with polar asphalt molecules can inhibit the plastic deformation of asphalt under long-term loads. When combined with steel slag powder, the rutting depth is reduced by 20% compared to asphalt modified with steel slag powder alone. In addition, the industrial solid waste utilization of phosphogypsum can reduce the mining of natural gypsum and reduce carbon emissions by 12 kg / ton of asphalt, achieving the dual goals of environmental benefits and performance improvement.

[0018] Preferably, the composite fiber is a mixture of polypropylene fiber and lignin fiber. In this invention, the composite fiber is a mixture of polypropylene fiber and lignin fiber. This composite fiber forms a reinforced structure in asphalt, which enhances the resistance to deformation, inhibits the generation and propagation of cracks, and keeps costs under control.

[0019] Preferably, the mass ratio of the polypropylene fiber to the lignin fiber is 2~8:1, more preferably 3~4:1.

[0020] Preferably, the length of the composite fiber is 2-7 mm, and more preferably 3-5 mm.

[0021] Preferably, the mass ratio of the composite fiber to the steel slag powder is 4-5:9-10. In this invention, by optimizing the proportion of the composite fiber and combining it with the steel slag powder, the compressive strength and high-temperature stability of asphalt are enhanced, while the addition of a specific proportion of fiber further enhances its crack resistance. The combination of these components effectively improves the performance of asphalt under high loads, especially by further improving its performance under high temperatures and heavy loads without affecting other properties.

[0022] Further preferably, the mass ratio of the composite fiber, steel slag powder, recycled waste rubber powder, and high-efficiency dispersant is 4~5:9~10:30~32:1~1.5. In this invention, the low-temperature modified asphalt with the preferred ratio of composite fiber, steel slag powder, recycled waste rubber powder, and high-efficiency dispersant exhibits superior overall performance.

[0023] Further preferred, the mass ratio of steel slag powder, phosphogypsum, recycled waste rubber powder, and base asphalt is 9~10:6~7:30~32:37~38.5. In this invention, the composite filling effect of steel slag powder and phosphogypsum, combined with the elastic modification of recycled waste rubber powder, creates a synergistic effect in low-temperature crack resistance: the elastic network of recycled waste rubber powder absorbs low-temperature shrinkage stress, the active bonding of steel slag powder enhances interfacial toughness, and the crystal support of phosphogypsum inhibits microcrack propagation. This results in a 18°C ​​reduction in the low-temperature cracking temperature (BT) of asphalt at -10°C compared to base asphalt, and a 50% increase in fatigue life (number of cyclic loading cycles) at -20°C. High-temperature stability synergy: the high-density particles of steel slag powder (density ≥3.5 g / cm³) contribute to this effect. 3 Together with the rigid crystals of phosphogypsum, it resists high-temperature deformation, while the swelling effect of waste rubber powder restricts the flow of asphalt molecules. The combined effect of these three factors raises the softening point of asphalt from 46℃ to over 58℃, and increases the viscosity index (VI) at 60℃ by 35%, meeting the stringent high-temperature performance requirements of heavy-duty transportation. Cost and environmental benefits are synergistic: Each ton of asphalt consumes 8-12 kg of steel slag powder and 5-8 kg of phosphogypsum, replacing traditional mineral powder and expensive modifiers, reducing raw material costs by 12%-18%. Simultaneously, it disposes of 15-20 kg of industrial waste, reducing landfill space and environmental pollution, aligning with the development direction of green building materials.

[0024] Further preferably, the high-performance low-temperature environmentally friendly asphalt is composed of the following components in parts by weight: 30-32 parts of waste rubber powder were recycled. 9-10 parts of steel slag powder 6-7 parts of phosphogypsum 9-10 parts of bio-based low-temperature activator 4-5 parts of composite fiber 1-1.5 parts of high-efficiency dispersant 37-38.5 parts of base asphalt. In this invention, the asphalt composition with the preferred component composition exhibits the best performance and significantly improves the overall performance of the mixture.

[0025] Secondly, the present invention provides a method for preparing the above-mentioned high-performance low-temperature environmentally friendly asphalt, comprising the following steps: 1) Mix and stir the recycled waste rubber powder, steel slag powder, phosphogypsum and composite fiber in proportion to obtain the first material.

[0026] 2) Mix the first material with the bio-based low-temperature activator to obtain the second material.

[0027] 3) Mix the second material with the high-efficiency dispersant to obtain the third material.

[0028] 4) The third material is heated, and the preheated base asphalt is added and stirred. In this invention, the asphalt performance is improved by optimizing the preparation process, and a "gradient mixing-step activation" mixing sequence is adopted to ensure synergistic effects among the components.

[0029] Preferably, in step 1), the stirring is carried out at 200~300 r / min for 6~8 min; the stirring temperature is 20~30℃.

[0030] Preferably, in step 2), the stirring is carried out at 350~500 r / min for 4~6 min; the stirring temperature is 20~30℃.

[0031] Preferably, in step 3), the stirring is carried out at 350~500 r / min for 2~4 min; the stirring temperature is 25~35℃.

[0032] Preferably, in step 4), the mixture is stirred at 100-200 r / min for 15-25 min; the stirring temperature is 120-140℃; the third material is heated to 100-120℃; and the base asphalt is preheated to 90-110℃. In this invention, the mixing sequence and speed control are optimized. First, recycled waste rubber powder, steel slag powder, phosphogypsum, and composite fibers are mixed to form a basic filler system. Then, bio-based low-temperature activator and high-efficiency dispersant components are added sequentially, and stirred at 200-500 r / min for 6-8 min, 4-6 min, and 2-4 min respectively. Before adding the base asphalt, the third material is heated to 100-120℃, and the preheated base asphalt (90-110℃) is added at a low speed of 100-200 r / min. Then, the speed is increased to 150-200 r / min and stirred for 15-25 min to reduce air bubbles and ensure uniform dispersion. By extending the curing time and controlling the temperature: after preparation, the product is cured at 120~140℃ for 30~60 minutes, with precise temperature control of ±5℃, so that the chemical reaction is more complete and the low-temperature crack resistance and high-temperature stability are improved.

[0033] The beneficial effects of this invention are at least as follows: 1. Synergistic optimization of superior low-temperature performance and cost-effectiveness This invention achieves a profound balance between low-temperature performance and economy through an innovative compounding of a bio-based low-temperature activator and recycled waste rubber powder. The bio-based low-temperature activator, with plant oil derivatives as its core component, reduces the viscosity of the asphalt system, lowering the mixing temperature to 100-110℃, a reduction of 20-30℃ compared to traditional modified asphalt, significantly reducing heating energy consumption. Its biomass-derived characteristics avoid the use of expensive petroleum-based additives, reducing raw material costs by 15%-20% year-on-year. The recycled waste rubber powder (40-60 mesh particle size) and the bio-based activator synergistically form an "elastic network-active cross-linking" structure, endowing the asphalt with excellent low-temperature flexibility, allowing it to operate at temperatures below -20℃, with a low-temperature bending strain ≥3500με. This effectively inhibits low-temperature cracking of the pavement, extending its service life by more than 30%, while balancing construction convenience and long-term economic benefits.

[0034] 2. High performance and long lifespan design across the entire temperature range In asphalt systems, elastic particles from recycled waste rubber powder and composite fibers (polypropylene fiber: lignin fiber = 3~4:1, length 3~5mm) construct a "three-dimensional reinforced network," significantly improving resistance to deformation and fatigue. The tensile ductility at room temperature is ≥100cm, and the ductility retention rate at -10℃ is ≥60%, adapting to high-frequency load impacts. Steel slag powder (specific surface area ≥400 m²) 2 The mixture of phosphogypsum (purity ≥85%) and active ingredients (per kg) enhances the density of asphalt mastic through adsorption and crystal structure filling. At 60℃, the dynamic viscosity is 25% higher than that of base asphalt, and the rutting factor (G* / sinδ) is ≥2.0MPa (60℃), effectively reducing high-temperature rutting. The synergistic effect of each component inhibits UV aging and water damage, resulting in a post-aging mass loss rate ≤0.8%, a residual ductility ratio ≥75%, and freeze-thaw cycle resistance ≥50 cycles. Durability is improved by more than 20% compared to traditional asphalt, significantly reducing road maintenance costs.

[0035] 3. Green environmental protection and high-value utilization of industrial solid waste The technical solution centers on "solid waste resource utilization," recovering 25-35 kg of waste rubber powder and 13-20 kg of industrial waste (steel slag powder + phosphogypsum) per ton of asphalt. This enables large-scale disposal of industrial solid waste such as waste rubber products, steel slag, and phosphogypsum, reducing solid waste emissions by over 30%, aligning with the requirements of "zero-waste city" construction and the circular economy. A bio-based low-temperature activator replaces traditional petroleum-based modifiers, reducing carbon emissions during production by 20%. The low mixing temperature process further reduces energy consumption during construction, resulting in an overall lifecycle carbon footprint that is 15-20% lower than traditional asphalt, contributing to the low-carbon transformation of road engineering. Furthermore, the use of inexpensive anionic surfactants (such as sodium dodecylbenzene sulfonate) as a high-efficiency dispersant avoids the introduction of harmful substances, resulting in excellent environmental performance of the system.

[0036] 4. Significant market competitiveness and broad construction adaptability Compared to existing low-temperature modified asphalt, the product of this invention possesses comprehensive advantages of "superior performance, low cost, and easy construction": the mixing temperature is 10-20℃ lower, the flexural strain at -20℃ is 15%-20% higher, and the production cost is 15%-20% lower. Furthermore, it requires no additional anti-aging agents or expensive modifiers, resulting in outstanding cost-effectiveness. Its wide operating temperature range allows for normal construction in environments as low as -10℃, extending the winter construction window and meeting the road construction needs of special scenarios such as frigid northern regions and high-altitude low-temperature areas. The product's performance covers multiple fields including high-grade highways, urban arterial roads, and airport runways, with technical indicators reaching international advanced levels. It possesses both economic value and social significance, and has broad market application prospects. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of this invention, not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0038] The endpoints and any values ​​of the ranges disclosed in this invention are not limited to the precise ranges or values; these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and individual point values, and individual point values ​​can be combined to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this invention. Where specific techniques or conditions are not specified in the embodiments of this invention, they shall be performed in accordance with the techniques or conditions described in the literature in the art, or in accordance with the product instructions. Devices, instruments, reagents, etc., used without specified manufacturers are all conventional products that can be purchased through legitimate channels. All experimental reagents and raw materials involved are commercially available products, and all reagents are analytical grade products.

[0039] Example 1 This embodiment provides a low-cost, high-performance, low-temperature environmentally friendly asphalt, the components of which are as follows by weight: 30 portions of recycled waste rubber powder (50 mesh particle size) 10 parts steel slag powder 6 parts phosphogypsum 10 parts of bio-based low-temperature activator 4 parts of composite fiber (polypropylene fiber: lignin fiber mass ratio of 3:1) 1.5 parts of high-efficiency dispersant 38.5 parts of base bitumen.

[0040] The bio-based low-temperature activator used is methyl epoxide oleate prepared from soybean oil (acid value of 6~12 mgKOH / g, saponification value of 170~190 mgKOH / g), and the high-efficiency dispersant is sodium dodecylbenzene sulfonate (HLB of 11~12).

[0041] This embodiment also provides a method for preparing the above-mentioned low-cost, high-performance, low-temperature environmentally friendly asphalt: According to the formula, the recycled waste rubber powder, steel slag powder, phosphogypsum and composite fiber are added to a low-speed mixer and stirred at 25℃ and 250r / min for 7 minutes.

[0042] Add the bio-based low-temperature activator, increase the rotation speed to 400 r / min, and stir for 5 min.

[0043] Add a high-efficiency dispersant, stir at 30°C for 3 minutes, heat the mixture to 110°C, add base asphalt preheated to 100°C, and stir at 130°C and 150 r / min for 20 minutes to obtain asphalt.

[0044] The obtained asphalt was tested for performance according to standard methods. The performance of asphalt and asphalt mixtures was tested (in accordance with the "Test Procedures for Asphalt and Asphalt Mixtures in Highway Engineering" (JTG E20-2011) and the "Low Temperature Modified Asphalt" (JT / T 1540-2025) standards). The mixing temperature was 105℃, which is lower than that of similar products; the flexural strain at -20℃ was above 3800 με, which is better than that of existing similar products; the performance remained excellent after aging, with good high temperature stability, and the cost was reduced by about 20%, showing obvious performance and cost advantages.

[0045] Example 2 This embodiment provides a low-cost, high-performance, low-temperature environmentally friendly asphalt, the components of which are as follows by weight: 32 portions of recycled waste rubber powder (40 mesh particle size) 9 parts of steel slag powder 7 parts phosphogypsum 9 parts of bio-based low-temperature activator Composite fiber (polypropylene fiber: lignin fiber mass ratio of 4:1, 3~5mm) 5 parts 1 part of high-efficiency dispersant 37 parts of base asphalt.

[0046] The bio-based low-temperature activator used is methyl epoxide oleate prepared from soybean oil (acid value of 6~12 mgKOH / g, saponification value of 170~190 mgKOH / g), and the high-efficiency dispersant is sodium dodecylbenzene sulfonate (HLB of 11~12).

[0047] This embodiment also provides the preparation of the low-cost, high-performance low-temperature cyclic asphalt, prepared and tested in the same way as in Example 1, with a mixing temperature of 105℃, a bending strain of over 4000 με at -20℃, a cost reduction of about 25%, and the best performance in aging properties, further proving the effectiveness and adjustability of the formulation.

[0048] Example 3 The same formulation and method as in Embodiment 1 were used, the only difference being that the mass ratio of polypropylene fiber to lignin fiber in the composite fiber was 2:1, and the fiber length was 2 mm. The prepared asphalt exhibited a flexural strain of 3500 με at -20℃ and a mixing temperature of 105℃, verifying the influence of fiber ratio on low-temperature performance.

[0049] Example 4 The same formulation and method as in Example 1 were used, except that the amount of steel slag powder and phosphogypsum was 8 parts each. Tests showed that the high-temperature stability of the asphalt (dynamic viscosity at 60℃) increased by 15%, demonstrating the synergistic filling effect of steel slag powder and phosphogypsum in optimizing high-temperature performance.

[0050] Comparative Example 1 1. The control group consists of representative low-temperature modified asphalt (similar products currently on the market) from this industry, tested according to standard methods.

[0051] 2. Experimental process and results The control group products underwent the same performance tests as in Examples 1 and 2. The comparison shows that the asphalt provided by the embodiments of the present invention is superior in terms of low mixing temperature, low-temperature crack resistance, high-temperature stability, durability, and environmental friendliness. The present invention is innovative and has significant advantages.

[0052] Comparative Example 2 The same formulation and method as Example 2 were used, except that: 24 parts of recycled waste rubber powder, 13 parts of steel slag powder, 9 parts of phosphogypsum, 9 parts of bio-based low-temperature activator, 5 parts of composite fiber, 2 parts of high-efficiency dispersant, and 37 parts of matrix asphalt were incorporated. This comparative example showed significantly inferior performance compared to Example 2 in all aspects.

[0053] Comparative Example 3 The same formulation and method as in Example 1 were used, except that no bio-based low-temperature activator was added. Tests revealed a significant decrease in all properties, especially a drop in mixing temperature to 120°C and a decrease in flexural strain to 2500 με at -20°C, indicating a significant decline in low-temperature performance.

[0054] Comparative Example 4 The same formulation and method as in Example 2 were used, except that the recycled waste rubber powder was replaced with an equal amount of ordinary rubber granules with a particle size of 80-90 mesh. Comparison showed that the properties of this comparative example were inferior, especially the low-temperature flexibility and crack resistance, which were significantly worse than those of Example 1.

[0055] Example 5 The same formulation and method as in Example 2 were used, except that the amount of recycled waste rubber powder was 33 parts and the amount of bio-based low-temperature activator was 8 parts.

[0056] Example 6 The same formula and method as in Example 2 were used, except that there were 6 parts of composite fiber and 12 parts of steel slag powder.

[0057] Example 7 The same formulation and method as in Example 2 were used, except that 4.5 parts of composite fiber, 8 parts of steel slag powder, 35 parts of recycled waste rubber powder, and 2 parts of high-efficiency dispersant were added.

[0058] Example 8 The same formulation and method as in Example 2 were used, with the only difference being 8 parts steel slag powder, 5 parts phosphogypsum, 35 parts recycled waste rubber powder, and 40 parts matrix asphalt. Test results from Examples 5-8 showed that the overall effect was good, but slightly worse than Example 2, and all individual effects were significantly better than those of Comparative Examples 1-4. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A high-performance, low-temperature, environmentally friendly asphalt, characterized in that, Includes the following components by weight: Recycle 25-35 parts of waste rubber powder 8-12 parts of steel slag powder 5-8 parts of phosphogypsum 8-12 parts of bio-based low-temperature activator 3-6 parts of composite fiber 1-2 parts of high-efficiency dispersant 30-65 parts of base asphalt.

2. The high-performance low-temperature environmentally friendly asphalt according to claim 1, characterized in that, The mass ratio of the recycled waste adhesive powder to the bio-based low-temperature activator is 28~33:8~11, preferably 30~32:9~10; Preferably, the mass ratio of the recycled waste rubber powder, bio-based low-temperature activator, and matrix asphalt is 28~33:8~11:30~45, and more preferably 30~32:9~10:37~38.

5.

3. The high-performance low-temperature environmentally friendly asphalt according to claim 2, characterized in that, The base asphalt is petroleum asphalt or natural asphalt; preferably, the aromatic content of the base asphalt is 20%~30%, and the resin content is 25%~35%. And / or, the recycled waste rubber powder is waste rubber product powder with a particle size of 40-60 mesh; And / or, the bio-based low-temperature activator is a fatty acid ester compound; preferably, the acid value of the bio-based low-temperature activator is 5~15 mg KOH / g, and the saponification value is 150~200 mg KOH / g.

4. The high-performance low-temperature environmentally friendly asphalt according to claim 3, characterized in that, The bio-based low-temperature activator is a fatty acid ester compound prepared from soybean oil or rapeseed oil, preferably a methyl oleate derivative or an ethyl linoleate derivative, and the methyl oleate derivative is preferably epoxy methyl oleate. And / or, the highly efficient dispersant is an anionic surfactant, preferably sodium dodecylbenzenesulfonate and / or sodium alkyl sulfate, more preferably sodium dodecylbenzenesulfonate; And / or, the hydrophilic-lipophilic balance value of the highly efficient dispersant is 10~14; And / or, the mass ratio of the bio-based low-temperature activator to the high-efficiency dispersant is 9~10:1~1.

5.

5. The high-performance low-temperature environmentally friendly asphalt according to any one of claims 1-4, characterized in that, The steel slag powder has a particle size of 30~80μm, preferably 40~60μm, and its main components are 40%~50% Fe3O4, 20%~25% CaO, and 15%~20% SiO2, with a free CaO content ≤3% and a specific surface area ≥400m². 2 / kg; And / or, the phosphogypsum is a waste residue from the phosphate fertilizer industry that has been washed with water to remove impurities, dried at low temperature, and ground to a particle size ≤50μm before use, and its main component is CaSO4・2H2O.

6. The high-performance low-temperature environmentally friendly asphalt according to any one of claims 1-5, characterized in that, The composite fiber is a combination of polypropylene fiber and lignin fiber. Preferably, the mass ratio of the polypropylene fiber to the lignin fiber is 2~8:1, more preferably 3~4:1; And / or, the length of the composite fiber is 2~7mm, preferably 3~5mm; And / or, the mass ratio of the composite fiber to the steel slag powder is 4~5:9~10.

7. The high-performance low-temperature environmentally friendly asphalt according to any one of claims 1-6, characterized in that, The mass ratio of the composite fiber, steel slag powder, recycled waste rubber powder, and high-efficiency dispersant is 4~5:9~10:30~32:1~1.5; And / or, the mass ratio of the steel slag powder, phosphogypsum, recycled waste rubber powder and matrix asphalt is 9~10:6~7:30~32:37~38.

5.

8. The high-performance low-temperature environmentally friendly asphalt according to any one of claims 1-7, characterized in that, It consists of the following components in parts by mass: 30-32 parts of waste rubber powder were recycled. 9-10 parts of steel slag powder 6-7 parts of phosphogypsum 9-10 parts of bio-based low-temperature activator 4-5 parts of composite fiber 1-1.5 parts of high-efficiency dispersant 37-38.5 parts of base asphalt.

9. The method for preparing high-performance low-temperature environmentally friendly asphalt according to any one of claims 1-8, characterized in that, Includes the following steps: 1) Mix and stir the recycled waste rubber powder, steel slag powder, phosphogypsum and composite fiber in a certain proportion to obtain the first material; 2) Mix and stir the first material with the bio-based low-temperature activator to obtain the second material; 3) Mix and stir the second material with the high-efficiency dispersant to obtain the third material; 4) Heat the third material, add the preheated base asphalt, and stir.

10. The method for preparing high-performance low-temperature environmentally friendly asphalt according to claim 9, characterized in that, In step 1), stir at 200~300 r / min for 6~8 min; the stirring temperature is 20~30℃; And / or, in step 2), stir at 350~500 r / min for 4~6 min; the stirring temperature is 20~30℃; And / or, in step 3), stir at 350~500 r / min for 2~4 min; the stirring temperature is 25~35℃; And / or, in step 4), stir at 100~200 r / min for 15~25 min; the stirring temperature is 120~140℃; heat the third material to 100~120℃; preheat the base asphalt to 90~110℃.