Direct vat set asphalt modifier prepared from coal liquefaction oil residues and preparation process thereof

Abstract

The present invention relates to the technical field of asphalt modifier preparation, and discloses a direct vat set asphalt modifier prepared from coal liquefaction oil residue and a preparation process thereof, the asphalt modifier comprises the following components: 30-50 parts of coal liquefaction oil residue, 5-15 parts of rosin resin, 5-10 parts of a plant-based plasticizer, 15-30 parts of a thermoplastic elastomer, 1-3 parts of an antioxidant, and 5-10 parts of an environment-friendly auxiliary agent, according to the direct vat set asphalt modifier prepared from the coal liquefaction oil residues and the preparation process of the direct vat set asphalt modifier, the segmented temperature control swelling technology is adopted, temperature and time parameters are accurately set according to the characteristics and reaction stages of all the raw materials, all the raw materials fully react under the optimal temperature condition, a stable and ideal molecular structure and interaction are formed, and the stability of the modifier is improved. The stability and uniformity of product quality are greatly guaranteed, the rosin resin and the plant-based plasticizer are selected to replace naphthenic oil, the rosin resin is derived from a natural renewable resource, and the negative influence on the environment in the production process is extremely small.

Description

Technical Field

[0001] The invention relates to the technical field of asphalt modifier preparation, in particular to a direct-injection asphalt modifier prepared by utilizing coal liquefaction oil residue and a preparation process thereof. Background Art

[0002] Asphalt pavement is the most important form of pavement in my country. With the expansion of domestic road construction and the rapid increase in traffic volume, the number of heavy and large vehicles has continued to increase, and the performance requirements for road asphalt have become higher and higher. Traditional road asphalt is very prone to rutting, cracks, lumps and other problems when facing the heavy load, high temperature and high-frequency stress brought by such vehicles. The innovative technical path of using coal liquefaction oil residue to prepare direct-investment asphalt modifier has emerged and has gradually received widespread attention in the industry. Coal liquefaction oil residue, as a raw material with a special chemical structure and properties, is prepared into a direct-investment asphalt modifier through a specific process. It is expected to be directly added to asphalt, effectively improving the key indicators of asphalt such as high-temperature stability, low-temperature crack resistance and fatigue resistance, thereby providing a highly potential new solution for improving asphalt performance and calmly coping with complex traffic conditions.

[0003] The existing announcement number is CN117362902A Chinese patent, discloses a functional instant asphalt direct injection agent and its preparation method, when mixing between 100 ° C-140 ° C, it is difficult to accurately control the temperature change in the swelling process, which will cause the material swelling degree to be inconsistent, and the temperature is too high and may cause some materials to swell excessively, while the temperature is too low and some materials will not swell sufficiently, thereby affecting the performance consistency and quality stability of the product, when the temperature is close to the lower limit of 100 ° C, the material preheating is insufficient, and the linear SBS and naphthenic oil are difficult to fully swell and interpenetrate, and the mixing uniformity is poor during subsequent blending, which affects the product performance consistency; and when the temperature is close to the upper limit of 140 ° C, it may cause the early decomposition or volatilization of some heat-sensitive additives, change the formula ratio, and reduce the product quality. At the same time, naphthenic oil comes from petroleum, and its production and use have certain negative effects on the environment, and with the increasing tension of petroleum resources, the cost may fluctuate greatly. In addition, naphthenic oil may interact with other additives under certain extreme conditions, affecting the long-term stability of product performance.

[0004] The existing Chinese patent with announcement number CN105985041A discloses an asphalt mixture additive and a preparation method thereof. Some raw materials (such as chlorinated paraffin resin and thiuram accelerators) have environmental risks. Chlorinated paraffin resin may release harmful substances during production, use or waste treatment, and thiuram accelerators are toxic to the human body. Summary of the invention

[0005] To solve all or part of the above problems, the object of the present invention is to provide a direct-injected asphalt modifier prepared from coal liquefaction oil residue and its preparation process, so as to solve the problem that it is difficult to accurately control the temperature change during the swelling process during mixing in the technology of the above comparative document, which will lead to inconsistent swelling degrees of the materials.

[0006] To achieve the above object, the present invention provides the following technical solution: A direct-injected asphalt modifier prepared from coal liquefaction oil residue and its preparation process, including the following steps: Step S1, preheat the coal liquefaction oil residue (coal liquefaction oil residue is also called coal liquefaction asphalt) at 110 - 130 °C for 1 - 2 hours; Step S2, adopt a segmented temperature-controlled swelling technology, first add rosin resin to the preheated coal liquefaction oil residue, stir at 120 - 130 °C for 30 - 60 minutes, and the stirring speed is 300 - 500 revolutions per minute; Step S3, then add a plant-based plasticizer, cool down to 110 - 120 °C, continue to stir for 30 - 60 minutes, and the stirring speed is 300 - 500 revolutions per minute; Step S4, add a thermoplastic elastomer, heat up to 130 - 140 °C, and stir at a speed of 500 - 800 revolutions per minute for 60 - 90 minutes; Step S5, add an antioxidant and an environment-friendly additive, the stirring speed is 300 - 500 revolutions per minute, the stirring time is 30 - 60 minutes, after mixing evenly, cool to room temperature, and obtain a direct-injected asphalt modifier with a particle size of 20 mesh through screening.

[0007] Furthermore, by weight, it includes the following components: 30 - 50 parts of coal liquefaction oil residue, 5 - 15 parts of rosin resin, 5 - 10 parts of plant-based plasticizer, 15 - 30 parts of thermoplastic elastomer, 1 - 3 parts of antioxidant, and 5 - 10 parts of environment-friendly additive.

[0008] Furthermore, the softening point of the coal liquefaction oil residue is 100 - 120 °C.

[0009] Furthermore, the plant-based plasticizer is specifically a compound of tall oil fatty acid and epoxidized soybean oil.

[0010] Furthermore, the thermoplastic elastomer is a linear styrene-butadiene-styrene block copolymer (SBS), and its styrene content is 30 - 40%.

[0011] Furthermore, the antioxidant is the hindered phenol antioxidant 1010, and the environment-friendly additive is nano calcium carbonate.

[0012] Furthermore, the particle size of the direct-injected asphalt modifier is 20 - 40 mesh.

[0013] Further, in steps S2, S3 and S4, the stirring process is carried out under a nitrogen protection atmosphere.

[0014] Further, the cooling method in step S5 is natural cooling or air cooling.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. A method for preparing a direct-injection asphalt modifier using coal liquefaction oil residue and its preparation process proposed by the present invention accurately controls the temperature at 110 - 130 °C during the material preheating stage to ensure the consistency of raw material preheating for different batches of products. Subsequently, a segmented temperature control swelling technology is adopted. According to the characteristics of each raw material and the reaction stage, the temperature and time parameters are accurately set, enabling each raw material to fully react under the optimal temperature conditions, forming a stable and ideal molecular structure and interaction, which greatly guarantees the stability and uniformity of product quality.

[0016] 2. A method for preparing a direct-injection asphalt modifier using coal liquefaction oil residue and its preparation process proposed by the present invention selects rosin resin and plant-based plasticizer to replace naphthenic oil. Rosin resin is derived from natural renewable resources and has minimal negative impact on the environment during the production process; the plant-based plasticizer comes from renewable raw materials such as vegetable oils and has good biodegradability. In all aspects of production, use, and waste treatment, it conforms to the concepts of environmental protection and sustainable development, effectively reducing the harm to the environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The disclosure of the present invention will be described with reference to the accompanying drawings. It should be understood that the drawings are only for illustrative purposes and are not intended to limit the scope of protection of the present invention. In the drawings, the same reference numerals are used to refer to the same components.

[0018] Figure 1 It is a process flow chart of the preparation steps of a method for preparing a direct-injection asphalt modifier using coal liquefaction oil residue proposed by the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0019] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the scope of protection of the present invention.

[0020] To further understand the content of the present invention, the present invention will be described in detail with reference to the accompanying drawings.

[0021] According to one aspect of the present invention, a method for preparing a direct-injection asphalt modifier using coal liquefaction oil residue, the preparation steps are as follows: Step 1: Preheat the coal liquefaction oil residue at 110 - 130 °C for 1 - 2 hours; Step 2: Adopt the segmented temperature-controlled swelling technology. First, add rosin resin to the preheated coal liquefaction oil residue, stir at 120 - 130 °C for 30 - 60 minutes, and the stirring speed is 300 - 500 revolutions per minute; Step 3: Then add the plant-based plasticizer, cool down to 110 - 120 °C, and continue to stir for 30 - 60 minutes with the stirring speed of 300 - 500 revolutions per minute; Step 4: Add the thermoplastic elastomer, heat up to 130 - 140 °C, and stir at a speed of 500 - 800 revolutions per minute for 60 - 90 minutes to fully swell the thermoplastic elastomer; Step 5: Add the antioxidant and the environmentally friendly additive, with the stirring speed of 300 - 500 revolutions per minute and the stirring time of 30 - 60 minutes. After mixing evenly, cool it to room temperature to obtain the direct-injection asphalt modifier. And the product has no halogen residue (detected by XRF), and the VOC emission is reduced by 62%.

[0022] Example 1 A method for preparing a direct-injection asphalt modifier using coal liquefaction oil residue, which comprises the following components: Weigh 30 parts of coal liquefaction oil residue (softening point 100 °C), 5 parts of rosin resin, 5 parts of plant-based plasticizer, 15 parts of linear SBS with a styrene content of 30%, 1 part of hindered phenol antioxidant 1010, and 5 parts of nano calcium carbonate by weight; The preparation steps are as follows: Step 1: Place the coal liquefaction oil residue in a preheating device and preheat it at 110 °C for 1 hour to make the coal liquefaction oil residue reach appropriate fluidity; Step 2: Adopt the segmented temperature-controlled swelling technology. Transfer the preheated coal liquefaction oil residue to a stirring container, introduce nitrogen for protection, add rosin resin, and stir at 120 °C at a speed of 300 revolutions per minute for 30 minutes to fully blend the rosin resin with the coal liquefaction oil residue; Step 3: Add the plant-based plasticizer, lower the temperature to 110 °C, and continue to stir at a speed of 300 revolutions per minute for 30 minutes to evenly disperse the plant-based plasticizer; Step 4: Add linear SBS, heat up to 130 °C, and stir at a speed of 500 revolutions per minute under nitrogen protection for 60 minutes to promote the full swelling of SBS; Step 5: Add antioxidant 1010 and nano calcium carbonate, stir at a speed of 300 revolutions per minute for 30 minutes. After mixing evenly, naturally cool it to room temperature. After screening, obtain the direct-injection asphalt modifier with a particle size of 20 mesh. It has no halogen residue detected by XRF, and the VOC emission is reduced by 62% compared with the traditional process.

[0023] Example 2 A direct-injection asphalt modifier prepared from coal liquefaction oil residue, comprising the following components: Weigh 35 parts of coal liquefaction oil residue (softening point 105 °C), 7 parts of rosin resin, 6 parts of plant-based plasticizer, 18 parts of linear SBS with a styrene content of 32%, 1.5 parts of hindered phenol antioxidant 1010, and 6 parts of nano calcium carbonate by weight; The preparation steps are as follows: Step 1: Preheat the coal liquefaction oil residue at 115 °C for 1.2 hours; Step 2: Add rosin resin and stir at 122 °C at 350 revolutions per minute for 40 minutes; Step 3: Add the plant-based plasticizer, cool down to 112 °C, and stir for 40 minutes; Step 4: Add linear SBS, heat up to 132 °C, and stir for 70 minutes; Step 5: Add antioxidant and nano calcium carbonate, stir evenly, and air-cool to room temperature to obtain a modifier with a particle size of 25 mesh, without halogen residue, and the VOC emission is reduced by 62%.

[0024] Example 3 A direct-injection asphalt modifier prepared from coal liquefaction oil residue, comprising the following components: Weigh 40 parts of coal liquefaction oil residue (softening point 110 °C), 9 parts of rosin resin, 7 parts of plant-based plasticizer, 20 parts of linear SBS with a styrene content of 34%, 2 parts of hindered phenol antioxidant 1010, and 7 parts of nano calcium carbonate by weight; The preparation steps are as follows: Step 1: Preheat the coal liquefaction oil residue at 120 °C for 1.5 hours; Step 2: Add rosin resin and stir at 125 °C for 50 minutes; Step 3: Add the plant-based plasticizer and stir at 115 °C for 50 minutes; Step 4: Add linear SBS and stir at 135 °C for 80 minutes; Step 5: Add antioxidant and nano calcium carbonate, and cool naturally after stirring to obtain a modifier with a particle size of 30 mesh, without halogen residue, and the VOC emission is reduced by 62%.

[0025] Example 4 Weigh 45 parts of coal liquefaction oil residue (softening point 115 °C), 11 parts of rosin resin, 8 parts of plant-based plasticizer, 22 parts of linear SBS with a styrene content of 36%, 2.5 parts of hindered phenol antioxidant 1010, and 8 parts of nano calcium carbonate by weight; The preparation steps are as follows: Step 1: Preheat the coal liquefaction oil residue at 125 °C for 1.8 hours.

[0026] Step 2: Add rosin resin and stir at 128°C for 55 minutes.

[0027] Step 3: Add plant-based plasticizer and stir at 118°C for 55 minutes.

[0028] Step 4: Add linear SBS and stir at 138°C for 85 minutes.

[0029] Step 5: Add antioxidant and nano calcium carbonate, and obtain a modifier with a particle size of 35 mesh after air cooling, with no halogen residue and a 62% reduction in VOC emissions.

[0030] Example 5 Weigh 50 parts of coal liquefaction oil residue (softening point 120°C), 15 parts of rosin resin, 10 parts of plant-based plasticizer, 30 parts of linear SBS with a styrene content of 40%, 3 parts of hindered phenol antioxidant 1010, and 10 parts of nano calcium carbonate by weight; The preparation steps are as follows: Step 1: Preheat the coal liquefaction oil residue at 130°C for 2 hours.

[0031] Step 2: Add rosin resin and stir at 130°C for 60 minutes.

[0032] Step 3: Add plant-based plasticizer and stir at 120°C for 60 minutes.

[0033] Step 4: Add linear SBS and stir at 140°C for 90 minutes.

[0034] Step 5: Add antioxidant and nano calcium carbonate, and obtain a modifier with a particle size of 40 mesh after natural cooling, with no halogen residue and a 62% reduction in VOC emissions.

[0035] Example 6 Weigh 32 parts of coal liquefaction oil residue (softening point 106°C), 6 parts of rosin resin, 5.5 parts of plant-based plasticizer, 16 parts of linear SBS with a styrene content of 31%, 1.2 parts of hindered phenol antioxidant 1010, and 5.5 parts of nano calcium carbonate by weight; The preparation steps are as follows: Step 1: Preheat the coal liquefaction oil residue at 110°C for 2.2 hours.

[0036] Step 2: Add rosin resin and stir at 121°C for 65 minutes.

[0037] Step 3: Add plant-based plasticizer and stir at 111°C for 65 minutes.

[0038] Step 4: Add linear SBS and stir at 131°C for 95 minutes.

[0039] Step 5: Add antioxidant and nano calcium carbonate, and cool naturally to obtain a modifier with a particle size of 35 mesh, without halogen residue, and the VOC emission is reduced by 62%.

[0040] Example 7 Weigh 38 parts of coal liquefaction oil residue (softening point 108°C), 8 parts of rosin resin, 6.5 parts of plant-based plasticizer, 19 parts of linear SBS with a styrene content of 33%, 1.8 parts of hindered phenol antioxidant 1010, and 6.5 parts of nano calcium carbonate by weight; The preparation steps are as follows: Step 1: Preheat the coal liquefaction oil residue at 110°C for 2.4 hours.

[0041] Step 2: Add rosin resin and stir at 123°C for 70 minutes.

[0042] Step 3: Add plant-based plasticizer and stir at 113°C for 70 minutes.

[0043] Step 4: Add linear SBS and stir at 133°C for 100 minutes.

[0044] Step 5: Add antioxidant and nano calcium carbonate, and cool naturally to obtain a modifier with a particle size of 30 mesh, without halogen residue, and the VOC emission is reduced by 62%.

[0045] Example 8 Weigh 42 parts of coal liquefaction oil residue (softening point 112°C), 10 parts of rosin resin, 7.5 parts of plant-based plasticizer, 21 parts of linear SBS with a styrene content of 35%, 2.2 parts of hindered phenol antioxidant 1010, and 7.5 parts of nano calcium carbonate by weight; The preparation steps are as follows: Step 1: Preheat the coal liquefaction oil residue at 110°C for 2.6 hours.

[0046] Step 2: Add rosin resin and stir at 126°C for 75 minutes.

[0047] Step 3: Add plant-based plasticizer and stir at 116°C for 75 minutes.

[0048] Step 4: Add linear SBS and stir at 136°C for 105 minutes.

[0049] Step 5: Add antioxidant and nano calcium carbonate, and cool naturally to obtain a modifier with a particle size of 25 mesh, without halogen residue, and the VOC emission is reduced by 62%.

[0050] Softening point data calculation chart of the segmented temperature-controlled swelling technology

[0051] In the current process, during the material preheating stage, the temperature is precisely controlled within 110 - 130 °C, providing a suitable and stable initial state for the material, ensuring the consistency of raw material preheating for products in different batches. In the subsequent reaction, a segmented temperature control swelling technology is adopted. For the addition and reaction stages of different raw materials, temperature and time parameters are precisely set. For example, when adding rosin resin, it is stirred at 120 - 130 °C for a specific time, and when adding plant - based plasticizer, the temperature is reduced to 110 - 120 °C for stirring. This precise and segmented temperature control method enables each raw material to fully react under the most suitable temperature conditions, forming a stable and ideal molecular structure and interaction. The current process selects rosin resin and plant - based plasticizer to replace naphthenic oil. Rosin resin is a natural renewable resource, and its production process has minimal negative impact on the environment. The plant - based plasticizer is derived from renewable raw materials such as plant oils and has good biodegradability, being environmentally friendly during production, use, and waste treatment processes, which conforms to the concepts of environmental protection and sustainable development.

[0052] Technical Standard for Preparing Direct - Injection Asphalt Modifier from Coal Liquefaction Oil Residue

[0053] Under normal circumstances, when the softening point increases, the penetration decreases. As the softening point gradually rises from 105 °C in Example 1 to 115 °C in Example 5, the penetration decreases from 45 (0.1 mm, 25 °C) to 35 (0.1 mm, 25 °C), and the penetration reduction rate increases from 8% to 18%. This is because an increase in the softening point means that the asphalt becomes harder and its ability to resist external penetration is enhanced, so the penetration decreases. A higher softening point makes the intermolecular interaction force of the asphalt stronger, and the molecular arrangement becomes more compact, macroscopically manifested as a decrease in penetration and an increase in material hardness. There is a certain synergistic relationship between the softening point and the ductility. In this scheme, as the softening point rises, the ductility shows a trend of first rising and then remaining relatively stable. From Example 1 to Example 5, as the softening point increases, the ductility increases from 20 cm (5 °C) to 30 cm (5 °C), and the ductility increase rate increases from 15% to 30%. Appropriately increasing the softening point helps to improve the internal structure of the asphalt, enhancing its flexibility and thus increasing the ductility. However, when the softening point exceeds a certain range, it may cause excessive cross - linking in the internal structure of the asphalt, resulting in the material becoming brittle and the ductility no longer increasing significantly or even decreasing. The increase in the softening point in this scheme optimizes the asphalt structure to a certain extent, effectively enhancing the ductility and the anti - deformation ability of the asphalt at low temperatures. Effect on the rutting factor G* / sinδ: The softening point is positively correlated with the rutting factor G* / sinδ. As the softening point increases, the rutting factor G* / sinδ gradually increases, from 1.8 kPa (60°C) in Example 1 to 2.8 kPa (60°C) in Example 5, and the promotion rate of the rutting factor increases from 12% to 25%. The increase in the softening point reflects the enhancement of the high-temperature stability of asphalt. The rutting factor G* / sinδ is an important indicator for measuring the high-temperature rutting resistance performance of asphalt. A higher softening point enables asphalt to have a stronger ability to resist deformation at high temperatures, with stronger intermolecular binding forces and less prone to flow deformation. Therefore, the increase in the rutting factor indicates that asphalt can better maintain the stability of the road surface under high-temperature and heavy-load conditions, reducing the occurrence of rutting diseases; The residue penetration ratio reflects the anti-aging performance of asphalt. In this solution, as the softening point increases, the residue penetration ratio also increases, from 65% (after RTFOT) in Example 1 to 75% (after RTFOT) in Example 5, and the promotion rate of the residue penetration ratio increases from 5% to 15%. Asphalt with a higher softening point has a relatively more stable internal structure. After undergoing the Rolling Thin Film Oven Test (RTFOT) to simulate aging, it can better maintain its own performance, with a smaller decrease in penetration, resulting in a higher residue penetration ratio. This shows that in this solution, by increasing the softening point, it helps to improve the anti-aging performance of asphalt and extend the service life of asphalt pavements;

[0054] In Comparative Example 1, the preparation steps are as follows: Step 1, preheat the internal mixer of the rubber-plastic blending device. Blend and stir linear SBS and naphthenic oil, and then sequentially add the compatibilizer and the quick solvent and blend and stir them before adding them into the internal mixer; the preheating temperature of the internal mixer is 100°C - 140°C, and the preheating time is 4 - 10 min.

[0055] Step 2, perform blending in the internal mixer at a constant temperature and at a constant speed, and stop blending when the torque reaches equilibrium; the blending temperature is 90 - 135°C, the blending rate is 30 - 80 r / min, and the blending time is 4 - 15 min. Generally, two minutes after the torque reaches equilibrium is used as the judgment basis.

[0056] Step 3, after the blending is completed, take out the blend and replace the extrusion die to further blend and extrude and pelletize the blend in Step 2. The die has a diameter of 1 - 3 mm, the blending temperature is 30 - 100°C, and the blending rate is 10 - 80 r / min.

[0057] Step 4, take the extruded strip obtained in Step 3 and perform machine shearing, and it should meet the requirement that the particle length after shearing ≤ 1000 μm to obtain the functional instant asphalt direct injection agent; The preparation steps in Comparative Example 2 are as follows: Prepare raw materials (kg) according to the following weight ratio: 60 of coal direct liquefaction residue, 15 of chlorinated paraffin resin, 0.05 of thiuram accelerator, 15 of recycled rubber, and 5 of coal tar; crush the coal direct liquefaction residue, chlorinated paraffin resin, thiuram accelerator, and recycled rubber into 100-mesh powders respectively through a Raymond mill; add the coal direct liquefaction residue powder, chlorinated paraffin resin powder, thiuram accelerator powder, and recycled rubber powder into a high-speed mixer and stir and mix to obtain a first mixture; among them, the stirring speed is 45 r / min and the stirring time is 12 min; heat the coal tar to 65 °C; add the heated coal tar to the first mixture for kneading treatment to obtain a second mixture; among them, the kneading temperature is 85 °C and the kneading time is 3.5 min except The segmented temperature control swelling technology is not used in the above comparative example. When the preheating temperature in the process approaches the lower limit of 100 °C, the insufficient preheating of the material affects the consistency of product performance. And when the temperature approaches the upper limit of 140 °C, it causes the premature decomposition or volatilization of heat-sensitive additives, changes the formulation ratio, and reduces the product quality. At the same time, naphthenic oil is derived from petroleum, and its production and use have certain negative impacts on the environment, and the cost may fluctuate greatly due to the tightness of petroleum resources. At the same time, under certain extreme conditions, it may interact with other additives and affect the long-term stability of product performance. In Comparative Example 2, the cross-linking agent used is one of alkylphenol formaldehyde resin, p-tert-butylphenol-acetylene resin, chlorinated paraffin resin, and thiuram accelerator. Chlorinated paraffin resin and thiuram accelerator have environmental protection risks. Chlorinated paraffin resin may release harmful substances during production, use, or waste treatment, and thiuram accelerator is toxic to the human body.

[0058] Regarding the change and effect of the softening point, in the improved solution, a segmented temperature control swelling technology is adopted, enabling raw materials such as coal liquefaction oil residue, rosin resin, plant-based plasticizer, and linear SBS to gradually swell and react at different temperature stages. At the lower temperature stage, the raw material molecules become active, laying the foundation for subsequent sufficient interaction. As the temperature rises, the intermolecular diffusion and cross-linking reaction become more sufficient, and the system structure becomes more stable and uniform. This process promotes the fusion between raw materials, forming a more perfect network structure, thereby effectively increasing the softening point of the product. At the same time, the rosin resin itself has a relatively high softening point, good viscosity, and thermal stability. Adding it to the formula is equivalent to introducing a high-softening-point component, directly increasing the softening point of the product. The plant-based plasticizer improves the processing performance of the system, enhances the cohesion between components, and also has a positive impact on the softening point. Moreover, after replacing chlorinated paraffin and naphthenic oil, the dilution of the system by low-softening-point substances is avoided, further promoting the increase of the product's softening point. The effect brought about by the increase in the softening point is significant. It enhances the stability of asphalt in high-temperature environments, reduces problems such as high-temperature deformation and flowing, enabling the paved road surface to maintain good shape and performance under hot weather and heavy traffic loads, and extending the service life of the road surface.

[0059] Furthermore, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Also, the terms "comprise", "include" or any other variant thereof are intended to cover non-exclusive inclusion, such that a process, method, article or device comprising a series of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article or device.

[0060] As described above, it is only the preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, makes equivalent substitutions or changes, and should be covered by the protection scope of the present invention.

Claims

1. A preparation process for directly adding type asphalt modifier using coal liquefaction oil residue, characterized in that: It includes the following steps: S1. Preheat the coal liquefaction oil residue at 110 - 130 °C for 1 - 2 hours; S2. Adopt the segmented temperature control swelling technology. First, add rosin resin to the preheated coal liquefaction oil residue, stir at 120 - 130 °C for 30 - 60 minutes, and the stirring speed is 300 - 500 revolutions per minute; S3. Then add the plant - based plasticizer, cool down to 110 - 120 °C, continue to stir for 30 - 60 minutes, and the stirring speed is 300 - 500 revolutions per minute; S4. Add the thermoplastic elastomer, heat up to 130 - 140 °C, and stir at a speed of 500 - 800 revolutions per minute for 60 - 90 minutes; S5. Add the antioxidant and the environment - friendly additive, with a stirring speed of 300 - 500 revolutions per minute and a stirring time of 30 - 60 minutes. After mixing evenly, cool it to room temperature, and obtain the direct - injection asphalt modifier with a particle size of 20 mesh through screening.

2. The preparation process according to claim 1, wherein: By weight, it includes the following components: 30 - 50 parts of coal liquefaction oil residue, 5 - 15 parts of rosin resin, 5 - 10 parts of plant - based plasticizer, 15 - 30 parts of thermoplastic elastomer, 1 - 3 parts of antioxidant, and 5 - 10 parts of environment - friendly additive.

3. The preparation process according to claim 1, characterized in that: The softening point of the coal liquefaction oil residue is 100 - 120 °C.

4. The preparation process according to claim 1, characterized in that: The plant - based plasticizer is specifically the compound of tall oil fatty acid and epoxidized soybean oil.

5. The preparation process according to claim 1, wherein: The thermoplastic elastomer is a linear styrene - butadiene - styrene block copolymer (SBS), and its styrene content is 30 - 40%.

6. The preparation process according to claim 1, characterized in that: The antioxidant is the hindered phenol antioxidant 1010, and the environment - friendly additive is nano - calcium carbonate.

7. The preparation process according to claim 1, characterized in that: The particle size of the direct - injection asphalt modifier is 20 - 40 mesh.

8. The preparation process according to claim 1, characterized in that: In steps S2, S3, and S4, the stirring process is carried out under a nitrogen - protection atmosphere.

9. The preparation process according to claim 5, characterized in that: The cooling method in step S5 is natural cooling or air cooling.

10. A method for preparing a direct - injection asphalt modifier using coal liquefaction oil residue, which is prepared by the method according to any one of claims 1 - 9.

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