High-dosage bio-oil activated rubber powder modified asphalt as well as preparation method and production system thereof

Abstract

The invention provides high-dosage bio-oil activated rubber powder modified asphalt as well as a preparation method and a production system thereof, and relates to the technical field of asphalt material preparation. The method comprises the following steps: stirring the rubber powder and the bio-oil for 45-60 minutes under the conditions that the temperature is 110 + / -5 DEG C and the negative pressure is-0.08 to-0.095 MPa; switching to nitrogen, pressurizing to 0.3-0.5 MPa, and stirring and mixing for 20-30 minutes to obtain bio-oil activated rubber powder; adding the bio-oil activated rubber powder into the matrix asphalt, and controlling the temperature to be 160 + / -5 DEG C and the speed to be 2500-5500 rpm; and shearing and mixing for 20-60 minutes to obtain the product. Based on the matrix asphalt, the mixing amount of the rubber powder is 20-35%, and the mixing amount of the bio-oil is 10-15%. According to the invention, permeation and storage of bio-oil in rubber powder are realized through a high-temperature negative pressure-nitrogen pressurization synergistic pretreatment process, an in-situ reservoir effect is formed to dynamically compensate loss of light components in an aging process, the material is endowed with self-repairing regeneration capacity and long-acting anti-aging performance, and the compatibility and high and low temperature performance of the material are improved; the method is especially suitable for a high-mixing-amount rubber powder modified asphalt system, and is simple in process and low in energy consumption.

Description

Technical Field

[0001] The present invention relates to the technical field of asphalt material preparation for road engineering, and particularly relates to a high-content bio-oil activated crumb rubber modified asphalt, a preparation method thereof, and a production system. Background Art

[0002] In the field of highway construction and maintenance, asphalt, as a key pavement material, its performance has a direct impact on the service life of the road and driving safety. To improve the performance of asphalt, crumb rubber is often used for modification to obtain crumb rubber modified asphalt. Crumb rubber modified asphalt exhibits good high-temperature stability, low-temperature flexibility, anti-aging property, anti-fatigue property, and water damage resistance, and is an excellent choice for environmentally friendly pavement materials. However, in the traditional preparation process, crumb rubber particles are prone to absorb the light components in asphalt, resulting in the deterioration of asphalt performance, decreased stability, increased viscosity, and poor workability. At the same time, currently, the processing temperature of crumb rubber modified asphalt usually remains at a relatively high temperature of 180-200 °C, with high energy consumption, and is prone to segregation, seriously affecting the storage stability and use effect of crumb rubber modified asphalt.

[0003] In view of these problems, there are solutions in the prior art that propose to modify crumb rubber asphalt with bio-oil to further optimize the performance of modified asphalt. For example, Chinese Patent Document CN118931213A discloses an anti-aging bio-based rubber asphalt material, its preparation method and application. In this solution, rubber powder and bio-oil are mixed in a mass ratio of 1:(0.5~1.5), and heated and stirred evenly to obtain Substance A; then it is swollen at room temperature to obtain bio-based expanded rubber, and the swelling time is 6h~18h; then it is swollen under microwave to obtain bio-based modified rubber, the power of the microwave is 300W~500W, the frequency of the microwave is 2000MHz~3000MHz, and the swelling time is 2min~8min; finally, the prepared bio-based modified rubber is added to the matrix asphalt at a ratio of 10%-20%, and stirred and reacted under heating conditions to obtain a bio-based rubber asphalt material, which can significantly improve the anti-aging performance of the asphalt material. In this solution, the main mechanism is to trigger the rupture of rubber molecular chains (chemical depolymerization) through high-frequency microwave vibration, so that the crumb rubber undergoes physical swelling at high temperature to form a porous structure. The essence of microwave is the cracking of materials caused by energy input, so this process will lead to the destruction of the rubber cross-linking network and sacrifice rubber elasticity to enhance bio-oil adsorption. Chinese Patent Document CN118146645A discloses a preparation method of modified asphalt, including: S1: mixing petroleum asphalt and rubber powder and then performing high-speed shearing to obtain rubber asphalt; S2: mixing the rubber asphalt with bio-oil at 120~150°C and then performing high-speed shearing to obtain modified asphalt; in the modified asphalt, the content of the rubber powder is 15~18wt%, and the content of the bio-oil is 5~10wt%. This solution adopts the process of "first modifying asphalt with rubber and then shearing with bio-oil". Its core mechanism is to rely on bio-oil as an external additive to directly improve the compatibility of rubber asphalt. Bio-oil only exists as a physical dispersion phase in the asphalt-crumb rubber interface layer. Its modification effect comes from the competitive adsorption of light components of asphalt and cannot penetrate into the crumb rubber cross-linking network. Its modification effect is limited to interface lubrication, and the modification effect still needs to be improved.

[0004] Moreover, the dosage of crumb rubber in the above solutions is controlled below 20%. This is because in traditional technologies, a high dosage of crumb rubber easily leads to crumb rubber agglomeration, a sharp increase in asphalt viscosity, and deterioration of low-temperature performance, and is not suitable for high-dosage crumb rubber modified asphalt systems.

[0005] Therefore, it is urgent to develop a crumb rubber modified asphalt and its preparation method that can improve the modification effect of crumb rubber modified asphalt, especially the modification effect of high-dosage crumb rubber modified asphalt, and has a simple process and low energy consumption. Summary of the Invention

[0006] The technical problem to be solved by the present invention is: to provide a high-loading bio-oil activated rubber powder modified asphalt, its preparation method and production system. The purpose is to, aiming at the defects existing in the prior art, adopt a high-temperature negative pressure-nitrogen pressurization synergistic pretreatment process to first prepare bio-oil activated rubber powder, and then prepare bio-oil activated rubber powder modified asphalt. By optimizing the production process, the compatibility between the rubber powder and the asphalt in the rubber powder modified asphalt can be improved, and the delamination and segregation phenomenon can be reduced; especially for high-loading rubber powder modified asphalt, the high and low temperature performance of the high-loading rubber powder modified asphalt can be improved, providing key technical support for the resource utilization of a high proportion of waste rubber powder, and at the same time simplifying the process and reducing production energy consumption.

[0007] To solve the above technical problems, the present invention adopts the following technical solutions:

[0008] In the first aspect, the present invention provides a preparation method of high-loading bio-oil activated rubber powder modified asphalt, including the following steps:

[0009] S1. Stir and mix the rubber powder and bio-oil at 110±5°C and a negative pressure of -0.08~-0.095 MPa for 45~60 min to promote the preliminary penetration of bio-oil into the rubber powder; then switch to nitrogen pressurization to 0.3~0.5 MPa and stir and mix for 20~30 min to force the bio-oil to fill the internal pores of the rubber powder, obtaining bio-oil activated rubber powder;

[0010] S2. Add the bio-oil activated rubber powder obtained in S1 to the hot matrix asphalt, control the temperature at 160±5°C, and control the shear speed at 2500-5500 rpm; shear and mix for 20-60 min to obtain bio-oil activated rubber powder modified asphalt;

[0011] Based on the mass of the matrix asphalt, the rubber powder content is 20~35% of the matrix asphalt; the bio-oil content is 10%~15% of the matrix asphalt.

[0012] Furthermore, to ensure the uniform mixing of the rubber powder and bio-oil, the process of step S1 is carried out in a rubber powder pretreatment tank. The rubber powder pretreatment tank is equipped with a stirring device. The stirring device includes a rotary drive and rotary blades. The rotary blades are arranged in the tank body. The rotary blades adopt a three-layer combined blade configuration of upper, middle and lower layers. During operation, the rotary drive controls the rotation speeds of the three layers of blades respectively. The rotation speed of the upper layer of blades is 60~90 rpm, which is used to generate strong shear force to break the rubber powder agglomerates; the rotation speed of the middle layer of blades is 30~60 rpm, which is used to promote radial diffusion; the rotation speed of the lower layer of blades is 15~30 rpm, which is used to enhance axial circulation and scrape the wall; at the same time, the rotary drive also controls the overall rotary blades to perform the following cyclic motion: rotate forward for 5 min, pause for 10 s, and then rotate backward for 3 min to eliminate the centrifugal delamination phenomenon.

[0013] Further, in S1, the nitrogen pressure is increased in a gradient manner to a preset pressure at a rate of 0.03~0.07 MPa / min.

[0014] Further, the bio-oil in step S1 is a renewable plant-based pyrolysis product rich in light components, which is prepared from agricultural and forestry waste rich in cellulose, hemicellulose and lignin. The agricultural and forestry waste includes corn straw, rice husk, wheat straw, wood chips, etc.

[0015] Further, the rubber powder in step S1 is particulate matter obtained by mechanically crushing waste tires, or particulate matter obtained by ambient temperature grinding of waste rubber conveyor belts or waste rubber seals. The particle size range of the particulate matter is controlled at 0.3 mm~0.6 mm.

[0016] In a second aspect, the present invention also provides a production system for high-loading bio-oil activated rubber powder modified asphalt that can implement the above preparation method, including a rubber powder pretreatment tank, a rubber powder modified asphalt high-speed shearing tank and a rubber powder modified asphalt storage tank connected in sequence; a bio-oil pretreatment rubber powder conveyor is connected between the rubber powder pretreatment tank and the rubber powder modified asphalt high-speed shearing tank, and a rubber powder modified asphalt conveyor is connected between the rubber powder modified asphalt high-speed shearing tank and the rubber powder modified asphalt storage tank;

[0017] It also includes a rubber powder conveying assembly, a bio-oil pumping assembly, a nitrogen pressurizing assembly, and a vacuum pump assembly connected to the rubber powder pretreatment tank; the rubber powder conveying assembly is used to quantitatively convey rubber powder to the rubber powder pretreatment tank, the bio-oil pumping assembly is used to quantitatively pump bio-oil to the rubber powder pretreatment tank, the nitrogen pressurizing assembly is used to pressurize the rubber powder pretreatment tank with nitrogen, and the vacuum pump assembly is used to achieve a negative pressure condition in the rubber powder pretreatment tank;

[0018] It also includes a hot asphalt conveying assembly, which is used to convey hot matrix asphalt to the rubber powder modified asphalt high-speed shearing tank;

[0019] The rubber powder pretreatment tank is provided with a temperature control device and a stirring device; the rubber powder modified asphalt high-speed shearing tank is also provided with a temperature control device and a stirring device; the rubber powder modified asphalt storage tank is also provided with a stirring device.

[0020] Further, the temperature control device of the rubber powder pretreatment tank includes a jacketed heat-conducting oil circulation heating device and a first PID temperature controller, which is used to control the temperature in the rubber powder pretreatment tank at 110±5 °C; its stirring device includes a rotary drive and rotary blades, and the rotary drive can drive the rotary blades to rotate and stir the materials in the tank.

[0021] Further, the rotating blades of the rubber powder pretreatment tank are arranged in the tank body, adopting a three-layer combined blade configuration of upper, middle and lower layers. The upper-layer blades are folding blade type blades, the middle-layer blades are spiral ribbon type blades, and the lower-layer blades are anchor type blades. The clearance between the outer edge of the anchor type blades and the tank wall is ≤5 mm, and a polytetrafluoroethylene (PTFE) or wear-resistant rubber scraper is provided; the rotary drive is arranged on the top of the rubber powder pretreatment tank, and is used to control the rotation speed, rotation time and rotation direction of the rotating blades.

[0022] Further, the temperature control device of the rubber powder modified asphalt high-speed shearing tank includes a jacketed heat-conducting oil circulation heating device and a second PID temperature controller, which is used to control the temperature in the rubber powder modified asphalt high-speed shearing tank at 160±5°C; its stirring device includes a high-speed shearing controller and a rotating high-speed shearing device. The high-speed shearing controller can drive the rotating high-speed shearing device to rotate and stir the materials in the tank and control the shearing speed and shearing time of the rotating high-speed shearing device.

[0023] Further, the stirring device of the rubber powder modified asphalt storage tank includes stirring blades and a stirring driver. The stirring blades are arranged in the rubber powder modified asphalt storage tank, and the stirring driver is arranged on the top of the rubber powder modified asphalt storage tank. The stirring driver is used to drive the stirring blades to rotate and stir the materials in the tank and control the stirring speed, rotation time and rotation direction of the stirring blades.

[0024] Further, the rubber powder conveying assembly includes a rubber powder storage box, a rubber powder conveying pipe, a blower, a spiral weighing scale and a first valve. The rubber powder conveying pipe connects the rubber powder storage box and the rubber powder pretreatment tank. The first valve, the blower and the spiral weighing scale are sequentially arranged on the rubber powder conveying pipe. The blower is used to avoid rubber powder agglomeration and remove impurities (dust) on the surface of the rubber powder, and the spiral weighing scale is used to control the rubber powder dosage.

[0025] Further, the bio-oil pumping assembly includes a bio-oil storage box, a bio-oil conveying pipe, a metering pump and a second valve. The bio-oil conveying pipe connects the bio-oil storage box and the rubber powder pretreatment tank. The second valve and the metering pump are sequentially arranged on the bio-oil conveying pipe. The metering pump is used to quickly introduce the bio-oil into the rubber powder pretreatment tank and control the bio-oil dosage.

[0026] Further, the nitrogen gas pressurization assembly includes a nitrogen gas tank, a nitrogen gas pressurization pipe, a third valve, a second pressure controller and a pressurization pump. The nitrogen gas pressurization pipe is used to connect the nitrogen gas tank and the rubber powder pretreatment tank. The third valve, the second pressure controller and the pressurization pump are arranged on the nitrogen gas pressurization pipe. The pressurization pump is used to quickly fill the rubber powder pretreatment tank with nitrogen gas and pressurize it. The second pressure controller is used to control the pressure in the rubber powder pretreatment tank at 0.3~0.5 MPa (gauge pressure). A pump suction type nitrogen gas concentration detector for detecting the nitrogen gas concentration in the nitrogen gas tank is provided at the bottom of the nitrogen gas tank.

[0027] Further, the vacuum pump assembly includes a vacuum pump, a vacuum extraction pipeline, a fourth valve, and a first pressure controller. The vacuum pump is connected to the bottom of the rubber powder pretreatment tank through the vacuum extraction pipeline. The fourth valve and the first pressure controller are arranged on the vacuum extraction pipeline. The first pressure controller is electrically connected to the vacuum pump and is used to control the pressure in the rubber powder pretreatment tank at -0.08 to -0.095 MPa (gauge pressure).

[0028] Further, the hot asphalt conveying assembly includes a hot asphalt storage tank, a hot asphalt conveyor, and a fifth valve. The hot asphalt conveyor connects the hot asphalt storage tank and the rubber powder modified asphalt high-speed shearing tank. The fifth valve is arranged on the hot asphalt conveyor;

[0029] A weight detector is provided at the bottom of the hot asphalt storage tank for controlling the mass of the hot asphalt added to the rubber powder modified asphalt high-speed shearing tank. A microwave heating device is installed in the body of the hot asphalt storage tank for controlling the temperature in the hot asphalt storage tank at 150 ± 10 °C.

[0030] Further, the bio-oil pretreated rubber powder conveyor, the hot asphalt conveyor, and the rubber powder modified asphalt conveyor adopt shaftless screw conveyors, and their quantities can be adjusted according to actual situations.

[0031] In a third aspect, the present invention also provides a high-loading bio-oil activated rubber powder modified asphalt prepared by the above preparation method or a high-loading bio-oil activated rubber powder modified asphalt produced by the above production system.

[0032] The raw materials of the high-loading bio-oil activated rubber powder modified asphalt include matrix asphalt, rubber powder with a mass percentage of 20 - 35% of the matrix asphalt, and bio-oil with a mass percentage of 10% - 15% of the matrix asphalt.

[0033] The present invention has the following beneficial effects:

[0034] The present invention provides a preparation method of high-loading bio-oil activated rubber powder modified asphalt. Through the high-temperature negative pressure - nitrogen pressurization synergistic pretreatment process, the directional penetration and storage of bio-oil inside the rubber powder are realized, forming an in-situ reservoir effect to dynamically compensate for the loss of light components during the aging process, endowing the material with self-healing and regeneration ability and long-term anti-aging performance, and improving the compatibility and high and low temperature performance of the material; it is especially suitable for high-loading rubber powder modified asphalt systems.

[0035] The solution of the present invention first prepares a bio-oil activated rubber powder by the method of synergistic physical penetration of negative pressure-nitrogen pressurization: 1. In the negative pressure stage (-0.08~-0.095MPa): Eliminate the gas retention in the pores through a vacuum environment, construct a capillary pressure gradient, and drive the bio-oil to achieve rapid spontaneous penetration of surface micropores at 110±5°C; 2. In the nitrogen pressurization stage (0.3~0.5MPa): Use the pressure of inert gas to drive the bio-oil to forcibly fill the deep pores of the rubber powder, and simultaneously achieve dual effects: (1) Physical barrier: The nitrogen atmosphere effectively inhibits the thermal oxidation reaction of the rubber powder; (2) Structure optimization: Form a dense oil film barrier to prevent the rubber powder from excessively absorbing the light components of asphalt during the subsequent asphalt modification process. Then, the prepared bio-oil activated rubber powder is added to the matrix asphalt to prepare a high-loading bio-oil activated rubber powder modified asphalt.

[0036] The solution of the present invention can achieve the following through this physical pressure gradient regulation: (1) Molecular structure preservation: Avoid the destruction of the rubber cross-linking network; (2) Gradient swelling mechanism: There is an outer-inner core swelling gradient (outer swelling rate > inner core) in the interaction between the rubber powder and the asphalt, and the "in-situ reservoir" (oil storage microcapsule) effect can be established; (3) Dynamic release characteristics: The light components of the bio-oil are supplied according to the "outer layer first release - inner core continuous compensation" mode; (4) Synergistic protection system: The dense oil film and the dynamic release act together to effectively delay the loss of light components during the asphalt aging process.

[0037] Different from the contradictory phenomenon in the traditional technology that the high rubber powder content leads to the improvement of high-temperature performance and the deterioration of low-temperature performance, the present invention can achieve the positive correlation improvement of the high and low-temperature performance of the high-loading rubber powder modified asphalt through the synergistic mechanism of the bio-oil in-situ reservoir effect and the nitrogen inert interface modification, providing key technical support for the high-proportion resource utilization of waste tire rubber powder.

[0038] The production system of the present invention has a series connection of a high-temperature negative pressure, a nitrogen pressurization, and a high-speed shearing unit, and can realize the integrated production of rubber powder pretreatment - asphalt modification.

[0039] Compared with the prior art, the present invention biologically activates rubber powder through a stepped pressure regulation process. Under specific temperature conditions, first, the retention of gas in the pores of the rubber powder is eliminated through a negative pressure environment, and a capillary pressure gradient is established to drive the preliminary penetration of bio-oil; subsequently, a nitrogen pressurization process is adopted to force the bio-oil to fill the deep pores of the rubber powder. This synergistic treatment mechanism constructs an in-situ reservoir effect inside the rubber powder, which can dynamically compensate for the loss of light components in the asphalt system during production and application. At the same time, the inert atmosphere of nitrogen effectively inhibits the oxidation of the rubber powder and optimizes the interfacial bonding performance. Subsequently, the rubber powder treated with negative pressure-nitrogen pressurized bio-oil and the matrix asphalt are subjected to a mechanical-thermal synergistic high-speed shearing process to construct a stable three-dimensional network structure, realizing the uniform dispersion of the rubber powder in the asphalt matrix and inhibiting the segregation phenomenon. By integrating key processes such as negative pressure penetration, nitrogen pressurization, high-speed shearing, and stirring and development through a modular production unit, continuous operation of bio-oil pretreatment of rubber powder and asphalt modification is achieved, while improving the high-temperature stability and low-temperature ductility, significantly reducing the system viscosity and production energy consumption.

[0040] The present invention combines the recycling of waste biomass resources and waste rubber, constructs a resource recycling system, and while improving the storage stability and workability during construction, provides an environmentally friendly high-performance asphalt material for road engineering. Brief Description of the Drawings

[0041] Figure 1 It is a schematic flow chart of the preparation method of the bio-oil activated rubber powder modified asphalt provided by the present invention.

[0042] Figure 2 It is a schematic structural diagram of the production system of the bio-oil activated rubber powder modified asphalt provided by the embodiment of the present invention.

[0043] Figure 3 It is a process flow chart of the production system provided by the embodiment of the present invention.

[0044] Figure 4 It is a schematic structural diagram of the rotating blade of the rubber powder pretreatment tank provided by the embodiment of the present invention.

[0045] Description of the drawings: 1. Rubber powder pretreatment tank; 2. Rubber powder storage tank; 3. Rubber powder conveying pipe; 4-1. First valve; 4-2. Second valve; 4-3. Third valve; 4-4. Fourth valve; 4-5. Fifth valve; 5. Fan; 6. Screw weigher; 7. Bio-oil storage tank; 8. Bio-oil conveying pipe; 9. Metering pump; 10. Vacuum pump; 11-1. First pressure controller; 11-2. Second pressure controller; 12. Nitrogen tank; 13. Nitrogen pressurizing pipe; 14. Pressurizing pump; 15-1. First PID temperature controller; 15-2. Second PID temperature controller; 16. Rotary drive; 17. Rotary blade; 17-1. Pitched blade; 17-2. Helical ribbon blade; 17-3. Anchor blade; 18. Safety relief valve; 19. Flow transmitter; 20. Bio-oil pretreated rubber powder conveyor; 21. Hot asphalt storage tank; 22. Hot asphalt conveyor; 23. Rubber powder modified asphalt high-speed shearing tank; 24. High-speed shearing controller; 25. Rotary high-speed shearing device; 26. Rubber powder modified asphalt conveyor; 27. Rubber powder modified asphalt storage tank; 28. Stirring drive; 29. Stirring blade; 30. Discharge port. Detailed implementation manners

[0046] The following will further explain the technical solutions in the embodiments of the present invention with reference to the drawings. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0047] Embodiment 1

[0048] See Figure 1 , the present invention provides a method for preparing bio-oil activated rubber powder modified asphalt, including the following steps:

[0049] S1. Stir and mix the rubber powder and bio-oil at 110 ± 5 °C and negative pressure of -0.08 to -0.095 MPa for 45 to 60 minutes to promote the initial penetration of bio-oil into the rubber powder; then switch to nitrogen pressurization to 0.3 to 0.5 MPa and stir and mix for 20 to 30 minutes to force the bio-oil to fill the internal pores of the rubber powder, obtaining bio-oil activated rubber powder.

[0050] During the nitrogen pressurization stage, a method of gradually increasing the pressure in a gradient manner at a rate of 0.03 - 0.07 MPa / min is adopted to gradually raise the pressure to the target pressure value. Generally, it is preferably controlled that the gradient pressure increase rate of nitrogen is 0.05 MPa / min. This method can effectively avoid the extrusion of bio - oil on the surface of the rubber powder due to pressure shock, and at the same time ensure the filling efficiency of the pores of the rubber powder. If the pressurization speed is too fast, the oil film on the surface of the rubber powder will break; if the pressurization speed is too slow, bio - oil will accumulate in local areas. The gradient pressure increase strategy provided by the present invention can enable bio - oil to gradually fill the pores of the rubber powder under the drive of nitrogen pressure, thereby avoiding the interface peeling phenomenon caused by pressure mutation.

[0051] In order to eliminate the centrifugal stratification phenomenon and ensure the uniform mixing of the rubber powder and bio - oil, the process of S1 is designed to be carried out in a rubber powder pretreatment tank. The rubber powder pretreatment tank is equipped with a stirring device. The stirring device includes a rotary drive and rotary blades. The rotary blades are arranged in the tank body. The rotary blades adopt a three - layer combined blade configuration of upper, middle and lower layers. During operation, the rotary drive controls the rotation speeds of the three - layer blades respectively. The rotation speed of the upper - layer blades is 60 - 90 rpm, which is used to generate strong shear force to break the agglomeration of the rubber powder; the rotation speed of the middle - layer blades is 30 - 60 rpm, which is used to promote radial diffusion; the rotation speed of the lower - layer blades is 15 - 30 rpm, which is used to enhance axial circulation and scrape the wall; at the same time, the rotary drive also controls the overall rotary blades to perform the following cyclic motion: rotate forward for 5 min, pause for 10 s, and then rotate backward for 3 min.

[0052] S2. Add the bio - oil activated rubber powder of S1 into the hot matrix asphalt, control the temperature at 160 ± 5 °C, and control the shear speed at 2500 - 5500 rpm; shear and mix for 20 - 60 min to obtain the bio - oil activated rubber powder modified asphalt.

[0053] During the preparation process, control the dosage of the rubber powder to be 20 - 35% of the mass of the matrix asphalt; the dosage of the bio - oil to be 10% - 15% of the mass of the matrix asphalt.

[0054] In a specific embodiment, the bio - oil in step S1 is a renewable plant - based pyrolysis product rich in light components prepared from agricultural and forestry waste rich in cellulose, hemicellulose and lignin.

[0055] Generally, the agricultural and forestry waste includes biomass raw materials such as corn straw, rice husk, wheat straw, and wood chips. The main chemical components of such bio-oils include esters (such as methyl heptanoate, methyl hexanoate, methyl octanoate, etc.), acids (such as short-chain fatty acids like acetic acid and palmitic acid; for example, rice husk bio-oil contains relatively high contents of acetic acid and butyric acid), aldehydes (including short-chain aldehydes such as hexanal and pentanal, which are typical products generated during the pyrolysis of cellulose and hemicellulose), ketones (such as 2-heptanone, acetone, and cyclopentanone, which are usually produced by the degradation of lignin and carbohydrates), and phenols (such as guaiacol, methoxyphenol, and syringol, which are usually produced by the pyrolysis of lignin), and also include furans (such as 2-furaldehyde (furfural), which mainly comes from the dehydration reaction of hemicellulose), aromatic hydrocarbons, and alkanes. The main light components it contains include aldehydes and ketones (such as hexanal and acetone), small molecule esters (such as methyl heptanoate and ethyl acetate), monocyclic phenols (such as phenol and guaiacol), short-chain fatty acids (such as acetic acid and butyric acid), furans (such as furfural), small molecule hydrocarbons (such as olefins and toluene), etc. Among them, light components usually refer to compounds with lower boiling points and smaller molecular weights, mainly including: aldehydes and ketones (such as hexanal and acetone), small molecule esters (such as methyl heptanoate and ethyl acetate), monocyclic phenols (such as phenol and guaiacol), short-chain fatty acids (such as acetic acid and butyric acid), furans (such as furfural), small molecule hydrocarbons (such as olefins and toluene). The light components in bio-oil can improve the rheological properties of asphalt, specifically manifested as: 1) Plasticization effect: Small molecule substances penetrate into the rubber powder particles, promoting swelling and dispersion; 2) Antioxidant property: Phenolic compounds inhibit the generation of aging products (such as a reduction in carbonyl compounds); 3) Interface strengthening: Esters enhance the affinity between asphalt and aggregates, improving the water damage resistance ability.

[0056] In a specific embodiment, the rubber powder in step S1 is particulate matter obtained by mechanically pulverizing waste tires or particulate matter obtained by ambient temperature grinding of waste rubber products (such as conveyor belts and seals), and the particle size range is controlled at 0.3 mm to 0.6 mm.

[0057] In the preparation method provided by the present invention, bio-activated rubber powder is first prepared, and then the matrix asphalt is modified by using the bio-activated rubber powder. During the preparation process of bio-oil activated rubber powder, negative pressure is first used to promote the interaction between the rubber powder and bio-oil to ensure that the bio-oil is fully absorbed by the rubber powder; then it is switched to nitrogen pressurization. By means of nitrogen pressurization, the bio-oil is promoted to enter the internal voids of the rubber powder, and under the action of pressure, a tight "oil film" is formed on the surface of the rubber powder to form an "interface layer", which can promote the interaction between the pretreated rubber powder and hot asphalt, improve the compatibility between the rubber powder and hot asphalt, and at the same time provide an anaerobic environment for the bio-oil pretreated rubber powder, which is more conducive to the rubber powder absorbing bio-oil. At the same time, it can avoid spontaneous combustion due to uneven heating during the process of bio-oil pretreating the rubber powder; a rotating device is provided in the rubber powder pretreatment tank for stirring the rubber powder and bio-oil, so that the rubber powder and bio-oil are heated evenly and the rubber powder absorbs bio-oil more fully.

[0058] In the negative pressure stage (-0.08~-0.095 MPa): The gas retention in the pores is eliminated through a vacuum environment to construct a capillary pressure gradient, driving the rapid spontaneous penetration of bio-oil into the surface micropores at 110±5°C; then in the nitrogen pressurization stage (0.3~0.5 MPa): The inert gas pressure is used to drive the forced filling of bio-oil into the deep pores of the rubber powder, achieving two functions simultaneously: (1) Physical barrier: The nitrogen atmosphere effectively inhibits the thermal oxidation reaction of the rubber powder; (2) Structure optimization: A dense oil film barrier is formed to prevent the rubber powder from excessively absorbing the light components of asphalt during the subsequent asphalt modification process. Then, the modified asphalt is prepared by adding the bio-oil-activated rubber powder obtained to the matrix asphalt.

[0059] In order to implement the preparation method of the present invention in this embodiment, this embodiment provides a production system for bio-oil-activated rubber powder modified asphalt, as Figure 2 shown. The production system includes a rubber powder pretreatment tank 1, a high-speed shear tank 23 for rubber powder modified asphalt, and a storage tank 27 for rubber powder modified asphalt connected in sequence; the rubber powder pretreatment tank 1 is connected to the high-speed shear tank 23 for rubber powder modified asphalt through a bio-oil pretreatment rubber powder conveyor 20, and a flow transmitter 19 is provided on the pipeline between the two. The high-speed shear tank 23 for rubber powder modified asphalt and the storage tank 27 for rubber powder modified asphalt are connected through a rubber powder modified asphalt conveyor 26.

[0060] It also includes a rubber powder conveying component, a bio-oil pumping component, a nitrogen pressurization component, and a vacuum pump component connected to the rubber powder pretreatment tank; the rubber powder conveying component is used to quantitatively convey rubber powder to the rubber powder pretreatment tank, the bio-oil pumping component is used to quantitatively pump bio-oil to the rubber powder pretreatment tank, the nitrogen pressurization component is used to pressurize the rubber powder pretreatment tank with nitrogen, and the vacuum pump component is used to achieve the negative pressure condition of the rubber powder pretreatment tank; it also includes a hot asphalt conveying component, and the hot asphalt conveying component is used to convey hot matrix asphalt to the high-speed shear tank for rubber powder modified asphalt.

[0061] As a preferred embodiment, the rubber powder conveying component in this embodiment includes a rubber powder storage box 2, a rubber powder conveying pipe 3, a fan 5, a spiral weighing scale 6, and a first valve 4-1. The rubber powder conveying pipe 3 connects the rubber powder storage box 2 and the rubber powder pretreatment tank 1, and the first valve 4-1, the fan 5, and the spiral weighing scale 6 are sequentially arranged on the rubber powder conveying pipe 5. The fan 5 is used to avoid rubber powder agglomeration and remove impurities (such as dust) on the surface of the rubber powder, and the spiral weighing scale 6 is used to control the amount of rubber powder used.

[0062] As a preferred embodiment, the bio-oil pumping assembly in this embodiment includes a bio-oil storage tank 7, a bio-oil delivery pipe 8, a metering pump 9, and a second valve 4-2. The bio-oil delivery pipe 8 connects the bio-oil storage tank 7 and the rubber powder pretreatment tank 1, and the second valve 4-2 and the metering pump 9 are sequentially arranged on the bio-oil delivery pipe 8. The metering pump 9 is used to quickly introduce bio-oil into the rubber powder pretreatment tank 1 and control the amount of bio-oil used.

[0063] As a preferred embodiment, the nitrogen pressurization assembly in this embodiment includes a nitrogen tank 12, a nitrogen pressurization pipe 13, a third valve 4-3, a second pressure controller 11-2, and a pressurization pump 14. The nitrogen pressurization pipe 13 is used to connect the nitrogen tank 12 and the rubber powder pretreatment tank 1, and the third valve 4-3, the second pressure controller 11-2, and the pressurization pump 14 are arranged on the nitrogen pressurization pipe 13; the pressurization pump 14 is used to quickly fill the rubber powder pretreatment tank 1 with nitrogen and pressurize it, and the second pressure controller 11-2 is used to control the nitrogen pressure in the rubber powder pretreatment tank 1 within a preset range (gauge pressure). A pump suction type nitrogen concentration detector for detecting the nitrogen concentration in the nitrogen tank is provided at the bottom of the nitrogen tank 12.

[0064] As a preferred embodiment, the vacuum pump assembly in this embodiment includes a vacuum pump 10, a vacuum pumping pipeline, a fourth valve 4-4, and a first pressure controller 11-1. The vacuum pump 10 is connected to the bottom of the rubber powder pretreatment tank 1 through the vacuum pumping pipeline, and the fourth valve 4-4 and the first pressure controller 11-1 are arranged on the vacuum pumping pipeline. The first pressure controller 11-1 is electrically connected to the vacuum pump 10 and is used to control the pressure in the rubber powder pretreatment tank 1 within a preset range (gauge pressure).

[0065] As a preferred embodiment, the hot asphalt delivery assembly in this embodiment includes a hot asphalt storage tank 21, a hot asphalt conveyor 22, and a fifth valve 4-5. The hot asphalt conveyor 22 connects the hot asphalt storage tank 21 and the rubber powder modified asphalt high-speed shearing tank 23, and the fifth valve 4-5 is arranged on the hot asphalt conveyor 22. A weight detector (not shown in the figure) is provided at the bottom of the hot asphalt storage tank 22 for controlling the quality of the hot asphalt added to the rubber powder modified asphalt high-speed shearing tank 23. A microwave heating device (not shown in the figure) is installed in the body of the hot asphalt storage tank 22 for controlling the temperature in the hot asphalt storage tank at 150 ± 10 °C.

[0066] The rubber powder pretreatment tank 1 in this embodiment is provided with a temperature control device and a stirring device; the rubber powder modified asphalt high-speed shearing tank 23 is also provided with a temperature control device and a stirring device; the rubber powder modified asphalt storage tank 27 is also provided with a stirring device.

[0067] Specifically, the temperature control device of the rubber powder pretreatment tank 1 includes a jacketed heat-conducting oil circulation heating device of the tank body and a first PID temperature controller 15-1. The jacketed heat-conducting oil circulation heating device is electrically connected to the first PID temperature controller 15-1 and is used to control the temperature in the rubber powder pretreatment tank at 110±5°C. Its stirring device includes a rotary driver 16 and rotary blades 17. The rotary driver 16 can drive the rotary blades 17 to rotate and stir the materials in the tank. The rotary driver 16 is arranged at the top of the rubber powder pretreatment tank 1 and is used to control the rotation speed, rotation time and rotation direction of the rotary blades 17. As a preferred embodiment, as Figure 4 shown, in this embodiment, the rotary blades of the rubber powder pretreatment tank 1 are arranged in the tank body and adopt an upper-middle-lower three-layer combined blade configuration. The upper-layer blades adopt folded-blade paddle-type blades 17-1, preferably folded-blade paddle-type blades at 45°. The middle-layer blades adopt spiral ribbon-type blades 17-2, and the lower-layer blades adopt anchor-type blades 17-3. The gap between the outer edge of the anchor-type blade 17-3 and the tank wall is ≤5mm, and a polytetrafluoroethylene (PTFE) or wear-resistant rubber scraper is inlaid and arranged.

[0068] Specifically, the temperature control device of the rubber powder modified asphalt high-speed shearing tank 23 includes a jacketed heat-conducting oil circulation heating device of the tank body and a second PID temperature controller 15-2. The jacketed heat-conducting oil circulation heating device is electrically connected to the second PID temperature controller 15-2 and is used to control the temperature in the rubber powder modified asphalt storage tank at 160±5°C. Its stirring device includes a high-speed shearing controller 24 and a rotary high-speed shearing device 25. The high-speed shearing controller 24 can drive the rotary high-speed shearing device 25 to rotate and stir the materials in the tank and control the shearing speed and shearing time of the rotary high-speed shearing device 25. The strong shearing force of the rotary high-speed shearing device 25 can effectively break the agglomeration of rubber powder particles, make them evenly dispersed in the asphalt, and avoid performance unevenness caused by local aggregation. The mechanical energy generated during the shearing process of the rotary high-speed shearing device 25 can activate the surface of the rubber powder, promote the physical and chemical cross-linking of the bio-oil and the rubber powder, improve the swelling and dispersion of the rubber powder in the asphalt, and the micron- or even nano-level shearing effect generated by the high-speed shearing can enhance the interfacial bonding between the bio-oil pretreated rubber powder and the asphalt, and further enhance the material compatibility.

[0069] Specifically, the stirring device of the rubber powder modified asphalt storage tank 27 includes a stirring driver 28 and stirring blades 29. The stirring blades 29 are arranged in the rubber powder modified asphalt storage tank 27, and the stirring driver 28 is arranged at the top of the rubber powder modified asphalt storage tank 27. The stirring driver 28 is used to drive the stirring blades 29 to rotate and stir the materials in the tank and control the stirring speed, rotation time and rotation direction of the stirring blades 29.

[0070] As a preferred embodiment, the bio-oil pretreatment rubber powder conveyor 20, hot asphalt conveyor 22, and rubber powder modified asphalt conveyor 26 in this embodiment adopt existing shaftless screw conveyors that can achieve the function of material transportation, and their quantities are adjusted according to actual situations.

[0071] Embodiment 2

[0072] As Figure 3 shown, this embodiment provides a process flow for producing the bio-oil activated rubber powder modified asphalt using the production system provided in Embodiment 1. As a preferred embodiment, it specifically includes the following steps:

[0073] 1. Rubber powder feeding: First, heat the rubber powder in the rubber powder storage tank 2 for 15 - 25 minutes. Open the first valve 4-1, and the fan 5 and the screw metering scale 6 start to work. The fan 5 is used to remove the dust in the rubber powder, and the screw metering scale 6 precisely controls the mass of the rubber powder transported through the rubber powder conveying pipe 3 to the rubber powder pretreatment tank 1.

[0074] 2. Bio-oil feeding: First, heat the bio-oil in the bio-oil storage tank 7 for 15 - 30 minutes. Open the second valve 4-2, and the metering pump 9 starts to work. The metering pump 9 precisely controls the mass of the bio-oil transported through the bio-oil conveying pipe 8 to the rubber powder pretreatment tank 1.

[0075] 3. Mixing of rubber powder and bio-oil: After heating the rubber powder and bio-oil in the rubber powder pretreatment tank 1 to 110 ± 5 °C, use the rotary drive 16 to control the rotation speeds of the rotary blades 17 on different layers respectively. The upper-layer blades rotate at 90 rpm (high speed), generating strong shear force to break the agglomeration of rubber powder; the middle-layer blades rotate at 60 rpm (medium speed) to promote radial diffusion; the lower-layer blades rotate at 30 rpm (low speed) to enhance axial circulation and scrape the wall. And use the rotary drive 16 to control the rotary blades 17 to perform the following cyclic motion: first rotate forward for 5 minutes, pause for 10 seconds, and then rotate backward for 3 minutes to eliminate the centrifugal stratification phenomenon and ensure the uniform mixing of rubber powder and bio-oil.

[0076] 4. High-temperature negative pressure: The temperature in the rubber powder pretreatment tank 1 is maintained at 110 ± 5 °C to prevent the increase in the viscosity of bio-oil and affect the penetration efficiency of bio-oil. In this embodiment, tire rubber powder is selected, and its main component is cross-linked vulcanized rubber. High temperature can break some sulfur bonds, promote the relaxation of molecular chains, increase the porosity, and facilitate the penetration of bio-oil. When the temperature does not exceed 120 °C, it is not easy to cause the volatilization of light components (such as phenols and aldehydes) in bio-oil.

[0077] Turn on the vacuum pump 10 and the fourth valve 4-4. Control the pressure in the rubber powder pretreatment tank 1 at -0.09 MPa (gauge pressure) through the first pressure controller 11-1 for a duration of 50 min. In the initial stage, slowly evacuate at -0.05 MPa to avoid rapid shrinkage of the particle surface and blockage of pores. After 10 min, reduce the pressure to -0.09 MPa and maintain it. High-temperature negative pressure can promote the interaction between rubber powder and bio-oil, and the negative pressure discharges the gas retained in the pores of the rubber powder, eliminating the capillary resistance, forming a pressure gradient, and driving the bio-oil to migrate into the pores.

[0078] 5. Nitrogen pressurization: Maintain the temperature in the rubber powder pretreatment tank 1 at 110 ± 5 °C. Turn on the pressure pump 14 and the third valve 4-3 to quickly fill the rubber powder pretreatment tank 1 with nitrogen from the nitrogen tank 12 through the nitrogen pressurization pipe 13. Control the pressure in the rubber powder pretreatment tank 1 at 0.4 MPa (gauge pressure) through the second pressure controller 11-2 for a certain period of time. Initially, increase the pressure to the target value at a rate of 0.05 MPa / min to avoid extrusion of bio-oil on the particle surface due to pressure shock. In the negative pressure stage, the gas in the pores has been removed, and in the pressurization stage, the pressure difference is further used to drive the bio-oil deeper into the pores of the rubber powder to optimize its infiltration effect. And using nitrogen pressurization can avoid the oxidation of bio-oil caused by oxygen (such as rancidity of fatty acid esters and polymerization of phenols). At the same time, nitrogen has a small molecular weight and a fast diffusion rate, which is easy to uniformly transmit pressure.

[0079] 6. Rubber powder discharging: After the nitrogen pressurization is completed, open the safety relief valve 18 and slowly release the pressure (rate < 0.05 MPa / min) to prevent the reverse infiltration of bio-oil in the pores of the rubber powder due to too rapid pressure drop. A small amount of nitrogen dissolved in the bio-oil is released during pressure relief, generating microbubble disturbances and breaking the local interfacial tension barrier (similar to the "air impact effect"), improving the infiltration uniformity. After the pressure relief is completed, open the flow transmitter 19 to control the mass of the bio-oil pretreated rubber powder transported to the rubber powder modified asphalt high-speed shearing tank 23.

[0080] 7. Matrix asphalt feeding: Open the hot asphalt storage tank 21 and the fifth valve 4-5, and transport a determined mass of hot asphalt to the rubber powder modified asphalt high-speed shearing tank 23 through the weight detector at the bottom of the hot asphalt storage tank 21.

[0081] 8. Output of crumb rubber modified asphalt: When the temperature in the high-speed shear tank 23 of the crumb rubber modified asphalt reaches a certain temperature and stabilizes, turn on the high-speed shear controller 24, and control the shear speed of the rotating high-speed shear device 25 to be 3500 rpm and the shear time to be 30 min. The shear force generated by high-speed shearing can break the agglomerates of bio-oil pretreated crumb rubber, evenly disperse it into micron-sized particles, and form a stable suspension system. The mechanical energy and heat energy generated by shearing activate the surface active groups (such as C=O, -OH) on the crumb rubber, and physically and chemically crosslink with the polar components in the asphalt to form a three-dimensional network structure, improving the elastic recovery rate. After shearing, open the valve at the lower discharge port 30 of the high-speed shear tank 23 of the crumb rubber modified asphalt, input the crumb rubber modified asphalt into the crumb rubber modified asphalt storage tank 27 through the crumb rubber modified asphalt conveyor 26, and turn on the stirring drive 28 provided at the top of the crumb rubber modified asphalt storage tank 27 to make the stirring blade 29 stir the crumb rubber modified asphalt to make the performance of the crumb rubber modified asphalt more stable.

[0082] The production system provided by the embodiment of the present invention has the advantages of compact structure, simple process, and good crumb rubber activation effect. Through the modular design of the pretreatment tank and the high-speed shear tank, it supports continuous production. At the same time, combined with the corresponding production process, through the two-stage pretreatment of first negative pressure and then nitrogen pressurization, at a specific temperature, first use the negative pressure environment to accelerate the opening of the internal pores of the crumb rubber particles and the penetration efficiency of bio-oil, and then use nitrogen pressurization to strengthen the filling of bio-oil into the internal voids of the crumb rubber, significantly improving the activation effect of the crumb rubber and laying a homogenization foundation for the subsequent preparation of modified asphalt; at the same time, the residual volatile substances in the crumb rubber can be synchronously removed in the negative pressure stage, and the nitrogen inert protection is adopted in the pressurization process to avoid oxidation side reactions; the pretreated crumb rubber and the hot matrix asphalt are synchronously heated and sheared and mixed in the high-speed shear tank, and the secondary dispersion and interface strengthening of the crumb rubber are realized through the mechanical-thermal synergistic effect, effectively solving the technical problems such as crumb rubber agglomeration and phase separation in the traditional process; using bio-oil as the crumb rubber activation medium to replace the traditional aromatic oil or coal tar, reducing the emission of toxic volatile substances.

[0083] In order to verify the feasibility and effectiveness of the solution of the present invention, it is described through the following specific examples and tests, and the following comparative examples are designed for comparison.

[0084] Comparative Example 1

[0085] This comparative example provides a traditional crumb rubber modification process, which specifically includes the following steps:

[0086] (1) Stirring stage: Heat the matrix asphalt to 180 °C (a relatively high temperature compared to the traditional crumb rubber modification process), add crumb rubber (not activated by bio-oil) while stirring, and keep stirring at a constant temperature for 20 min; the crumb rubber dosage is 20% of the asphalt mass.

[0087] (2) Shearing stage: The mixture was sheared at a high speed for 10 min at a rotation speed of 4500 r / min.

[0088] (3) Development stage: Stirring was continued at 180 °C for 30 min until uniform to obtain the ordinary crumb rubber modified asphalt.

[0089] Comparative Example 2

[0090] This comparative example provides a conventional crumb rubber modified asphalt production system. The main difference from the production system provided in Example 1 lies in that its crumb rubber pretreatment tank adopts a conventional rotating blade structure and motion mode, and the specific differences are shown in Table 1 below:

[0091]

[0092] In the following embodiments and tests, the base asphalt was selected from A-70# petroleum asphalt produced by Dongguan Taihe Asphalt Co., Ltd.; the crumb rubber was selected from waste truck tire crumb rubber provided by Guangxi Transportation Science & New Materials Technology Co., Ltd.; the bio-oil was selected from waste plant-based bio-oil produced by Nantong Yuhao Chemical Technology Co., Ltd. The basic performance indexes of the bio-oil, crumb rubber and base asphalt used are shown in Tables 2, 3 and 4 respectively.

[0093]

[0094]

[0095]

[0096] (I) Influence of nitrogen pressurization time and shearing temperature on the performance of modified asphalt

[0097] Referring to the preparation methods, systems and processes provided in Example 1 and Example 2, the preparation of crumb rubber modified asphalt of the following groups was carried out: among them, the crumb rubber dosage was designed to be 20% and 30% of the mass of the base asphalt respectively, the bio-oil dosage was designed to be 10% of the asphalt mass, the temperature inside the high-speed shearing tank of the crumb rubber modified asphalt was designed to be 160 °C and 180 °C, and the nitrogen pressurization time was designed to be 0 min, 10 min, 20 min and 30 min.

[0098] The Brookfield viscosity test was carried out on all the obtained asphalts at 160 °C in accordance with the standard T0625—2011. The test results are shown in Table 5.

[0099] Table 5 Viscosity test results of different groups (I) (unit: mPa·s)

[0100]

[0101] From the data in the above table, it can be seen that when the nitrogen pressurization time is in the range of 20 - 30 min, the deep filling of the pores of the rubber powder by the bio - oil can be effectively achieved. When the pressurization time exceeds 20 min, the trend of viscosity decrease slows down (for example, when the nitrogen pressurization time is extended to 30 min, the viscosity under the condition of 30% dosage and 160 °C further decreases to 461.2 mPa·s, only decreasing by about 4.8% compared with 20 min), indicating that the pore filling is close to saturation at this time. Therefore, extending the pressurization time can further optimize the pore filling effect of the rubber powder, but the marginal benefit decreases. The preferred pressurization time is 20 - 30 min to balance the process efficiency and performance optimization.

[0102] It can also be found from the experimental results in Table 5 that the nitrogen pressurization treatment process described in the solution of the present invention has a significant regulatory effect on the viscosity of the rubber - powder modified asphalt. Under the conditions of the same rubber - powder dosage and shear temperature, as the nitrogen pressurization time extends (0 min - 30 min), the viscosity of the modified asphalt shows a gradient - decreasing trend. Among them, under the condition of 30% rubber - powder dosage and 160 °C shear temperature, the viscosity reduction reaches 55.1%, proving that the pressurization treatment can effectively improve the dispersion of the rubber powder and promote the bio - oil release compensation effect.

[0103] By comparing the data of different shear temperatures, it is found that the bio - oil activated rubber powder obtained by nitrogen pressurization treatment and shearing modification at 180 °C can further reduce the viscosity value, indicating that there is a synergistic effect between the modified shear temperature and the pressurization time of rubber - powder activation. Especially, the viscosity optimization effect of the pressurization treatment on the high - rubber - powder - dosage system (30%) is more significant, and the absolute value of its viscosity reduction reaches 594.7 mPa·s (under the condition of 160 °C), fully verifying the adaptability of the process method of the present invention to the high - dosage system. Through "bio - oil gradient activation" and "nitrogen interface engineering", the present invention can realize the coordinated optimization of the high - and low - temperature performance of the high - dosage rubber - powder modified asphalt and solve the inherent contradictions of the traditional process. The 30% high dosage can not only improve the resource recycling efficiency, but also endow the material with self - compensation performance through the dynamic oil - storage mechanism, providing key technical support for the application of high - proportion waste tire rubber powder in road engineering. In addition, the significant viscosity improvement effect is still maintained at 180 °C high - temperature conditions, which also confirms the inhibitory effect of the nitrogen inert atmosphere on the thermal oxidation of the rubber powder.

[0104] Therefore, it can be proved from the test data of each group in this embodiment that through promoting the bio - oil gradient penetration and dynamic compensation mechanism, the nitrogen pressurization treatment can effectively weaken the interaction force between rubber - powder particles, improve the interfacial compatibility between the rubber powder and asphalt, thereby reducing the system viscosity and enhancing the workability. This result provides a key basis for the optimization of process parameters, proving that the present invention can achieve precise control of the rheological properties of the modified asphalt by regulating the combination of pressurization time and temperature. At the same time, the low - dispersion characteristics of the test data confirm the precise controllability of the process parameters and meet the stability requirements of industrial continuous production.

[0105] (2) Influence of rubber powder content and bio - oil content on the properties of modified asphalt

[0106] Referring to the preparation methods, systems and processes provided in Example 1 and Example 2, the preparation of rubber - powder modified asphalt in the following groups was carried out: the rubber powder content was designed to be 20%, 25%, 30%, 35% of the mass of the matrix asphalt respectively, the bio - oil content was designed to be 10%, 12.5%, 15% of the mass of the asphalt, the temperature inside the high - speed shear tank of the rubber - powder modified asphalt was designed to be 160 °C, and the nitrogen pressurization time was designed to be 20 min. The Brookfield viscosity test was carried out on all the obtained asphalts at 160 °C according to the standard T0625—2011. The test results are shown in Table 6.

[0107]

[0108] It can be seen from the data in Table 6 that when the rubber powder content increases from 20% to 35%, if the bio - oil content is fixed at 10%, the viscosity surges from 315.2 mPa·s to 619.8 mPa·s (an increase of 96.5%), significantly increasing the construction difficulty; however, when the bio - oil content is simultaneously increased to 15%, the viscosity of the 35% rubber powder system drops to 497.4 mPa·s, a 19.7% decrease compared to the combination of 35% rubber powder + 10% bio - oil. This indicates that the activation effect of the bio - oil on the rubber powder in the present invention can effectively offset the viscosity deterioration effect brought by high content. Especially at a high rubber powder content of 30%, when the bio - oil content increases from 10% to 15%, the viscosity decreases by 17.8% (from 484.6 to 398.5 mPa·s), indicating the continuous improvement of the bio - oil dynamic release mechanism on the lubrication of the rubber powder - asphalt interface.

[0109] When the rubber powder content exceeds 30%, the growth rate of the system viscosity accelerates. Specifically, under the condition that the bio - oil content is 15%, when the rubber powder content is increased from 30% to 35%, the system viscosity increases by 98.9 mPa·s, and this increase is higher than the viscosity increase when the rubber powder content is increased from 25% to 30% (72.9 mPa·s). However, compared with the viscosity of the modified asphalt prepared by the traditional process in Comparative Example 1 at 160 °C (which is 2201 mPa·s), the high - content system of the present invention's process (bio - oil content 15% and rubber powder content 35%) can still achieve a 77% viscosity reduction, indicating the regulation ability of the negative - pressure - nitrogen pressurization synergistic process on the ultra - high - content system.

[0110] To further verify the adaptability of the process of the present invention to ultra-high dosage crumb rubber modified asphalt, in this embodiment, the groups with the crumb rubber dosage designed as 30% and 35% of the mass of the base asphalt and the bio-oil dosage designed as 15% of the mass of the base asphalt, and the bio-oil activated crumb rubber modified asphalt obtained were used as the experimental groups. And according to the preparation process provided in Comparative Example 1, with the crumb rubber dosage designed as 20%, the prepared ordinary crumb rubber modified asphalt was used as the control. Through the dynamic shear rheological test and the bending beam rheological test, the high and low temperature performance characteristics were compared and analyzed. The test results are shown in Table 7. Among them, the S value characterizes the low temperature brittleness of the asphalt (the larger the S value, the harder and more brittle), and the m value reflects the stress dissipation ability (the larger the m value, the better the dissipation ability).

[0111] Table 7 Performance evaluation indexes of modified asphalt in each group

[0112]

[0113] As can be seen from the data in Table 7, the high dosage bio-oil activated crumb rubber (30%, 35%) modified asphalt prepared by the system and process provided by the present invention still has better high and low temperature performance compared with the ordinary crumb rubber (20% dosage) modified asphalt.

[0114] (3) Influence of shear temperature on the performance of modified asphalt

[0115] Referring to the preparation methods, systems and processes provided in Example 1 and Example 2, the preparation of crumb rubber modified asphalt in the following groups was carried out: among them, the crumb rubber dosages were respectively designed as 20% and 30% of the mass of the base asphalt, the bio-oil dosage was designed as 10% of the mass of the asphalt, the temperatures inside the high-speed shear tank of the crumb rubber modified asphalt were respectively designed as 155 °C, 160 °C, 165 °C, and the nitrogen pressurization time was designed as 20 min.

[0116] The Brookfield viscosity test was carried out on all the obtained asphalts at 160 °C according to the standard T0625-2011. The test results are shown in Table 8.

[0117]

[0118] The data in Table 8 show that within the shear temperature range of 155-165 °C of the present invention's scheme, the viscosity value of the modified asphalt can be stably within the fluctuation range of ±5%, with high stability. Although the traditional high temperature process (180-200 °C) can reduce the viscosity, it often causes bio-oil loss and the performance is not stable.

[0119] (4) Influence of the rotating blade structure and motion mode of the crumb rubber pretreatment tank on the performance of modified asphalt

[0120] Referring to the production process provided in Example 2, the crumb rubber dosage was designed as 30% of the mass of the base asphalt, and the bio-oil dosage was designed as 10% of the base asphalt.

[0121] The modified asphalt produced by the production system of Comparative Example 2 was designated as the control group, and the modified asphalt produced by the production system provided in Example 1 was designated as the test group. The following tests were carried out in accordance with the standard "Test Procedures for Bitumen and Bituminous Mixtures for Highway Engineering" JTG E20 - 201 (T 0661 - 2011).

[0122] First, the unaged modified asphalt sample was heated to 163 °C and then poured into an aluminum tube. Then, the aluminum tube containing the modified asphalt sample was placed in an oven at 163 °C and kept at a constant temperature for 48 h. After that, the aluminum tube was transferred to a refrigerator at - 10 °C and placed for 4 hours. After completing the above operations, the sample in the aluminum tube was equally divided into three sections below the liquid level, and one - third samples from the top, middle, and bottom were taken to test their softening points. The softening point difference between the modified asphalt samples at the upper and lower ends of the sample tube was used as the evaluation index. The smaller the softening point difference, the smaller the segregation degree of the modified asphalt. When the softening point difference is lower than 2.5 °C, it is considered that the storage stability of the modified asphalt during transportation and storage is good. The results are as follows:

[0123]

[0124] From the data in Table 9 above, it can be seen that the crumb rubber modified asphalt produced by the production system provided in Example 1 of the present invention has better stability than the crumb rubber modified asphalt produced by the crumb rubber pretreatment tank in the control group's conventional production system.

[0125] (V) High - and low - temperature performance and anti - aging performance tests

[0126] Settings for each treatment group:

[0127] Treatment group 1: Ordinary crumb rubber modified asphalt produced by the process provided in Comparative Example 1, with the crumb rubber content being 20% of the matrix asphalt;

[0128] Treatment group 2: According to the JTG E20 - 2011 specification, the ordinary crumb rubber modified asphalt produced in Treatment group 1 was subjected to thermal - oxidative aging treatment using a SYD - 0610 type rotating thin - film oven (RTFO) and a PR9300 type pressure aging tester (PAV) to obtain long - term aged crumb rubber modified asphalt.

[0129] The specific method for short - term aging treatment is as follows: Set the short - term aging test temperature to 163 °C ± 0.5 °C, place a standard sample bottle of 35 g ± 0.5 g of the asphalt sample to be aged, set the rotation speed of the annular rack to 15 r / min, and age for 85 min to obtain a short - term aged asphalt sample.

[0130] The long-term aging treatment method is as follows: The temperature for the long-term aging test is 100°C. Place 50 g ± 0.5 g of the asphalt specimen after short-term aging in an aging tray to form an asphalt film with a thickness of 3.2 mm. Set the air pressure to 2.1 ± 0.1 MPa and the aging time to 20 h ± 10 min.

[0131] Treatment group 3: Referring to the preparation methods, systems, and processes provided in Example 1 and Example 2, the rubber powder content is designed to be 20% of the base asphalt, and the bio-oil content is designed to be 10% to obtain bio-oil activated rubber powder modified asphalt.

[0132] Treatment group 4: Referring to the treatment method of treatment group 2, perform thermal-oxidative aging treatment on the bio-oil activated rubber powder modified asphalt prepared in treatment group 3 to obtain long-term aged bio-oil activated rubber powder modified asphalt.

[0133] Treatment group 5: Use tall oil as a rejuvenator. Tall oil, as a by-product of the paper industry, contains a large amount of unsaturated fatty acid components and a certain amount of fatty acids with polyunsaturated carbon bonds. The basic performance indicators of tall oil are shown in Table 10. The preparation process is as follows: Heat the long-term aged rubber powder modified asphalt obtained in treatment group 2 to 180°C, then add 10% of its mass of tall oil, and mix thoroughly with a stirrer to obtain recycled rubber powder composite modified asphalt.

[0134]

[0135] Perform a temperature sweep test on the modified asphalt obtained in each of the above treatment groups at 64°C using a dynamic shear rheometer. The test process refers to AASHTO T 315, and the high-temperature viscoelastic properties of the asphalt are characterized by the rutting factor (G* / sinδ). The test results are shown in Table 11.

[0136] Measure the creep stiffness (S) and creep rate (m) of the ordinary rubber powder modified asphalt in treatment group 1, the long-term aged rubber powder modified asphalt in treatment group 2, the recycled rubber powder composite modified asphalt in treatment group 5, the bio-oil activated rubber powder modified asphalt in treatment group 3, and the long-term aged bio-oil activated rubber powder modified asphalt in treatment group 4 at -18°C through a bending beam rheology test (BBR) to evaluate their low-temperature performance. Among them, the S value characterizes the low-temperature brittleness of the asphalt (the larger the S value, the harder and more brittle), and the m value reflects the stress dissipation ability (the larger the m value, the better the dissipation ability). The test results are shown in Table 6.

[0137] Table 11 Results of rutting factor and BBR test

[0138]

[0139] It was found from the experimental results in Table 11 that in terms of high-temperature performance, the rutting factor of the bio-oil activated crumb rubber modified asphalt of the present invention (3218.0 Pa) was reduced by 53.9% compared with that of the ordinary crumb rubber modified asphalt (6982.4 Pa), which confirmed that the bio-oil inhibited the viscoelastic degradation caused by excessive swelling of the crumb rubber through the negative pressure-nitrogen pressurization synergistic process. After long-term aging, the increase in its rutting factor was only 181.1% (9046.1 Pa), far lower than the 244.7% increase (24056 Pa) of the ordinary crumb rubber modified asphalt, indicating that the oil storage microcapsule structure formed by the activation of bio-oil under negative pressure-nitrogen pressure could dynamically compensate for the loss of light components during the aging process and effectively delay the performance degradation.

[0140] In terms of low-temperature performance, the creep stiffness S value (35.8 MPa) of the bio-oil activated crumb rubber modified asphalt was reduced by 72.0% compared with that of the ordinary crumb rubber modified asphalt (128 MPa), and the creep rate m value (0.439) was increased by 35.5%, indicating that its low-temperature stress relaxation ability was significantly improved. After aging, the S value only increased by 45.5% (52.1 MPa), and the m value remained 0.402, which confirmed the long-term protection of the dynamic release mechanism of bio-oil on the low-temperature durability of the material.

[0141] In terms of anti-aging and regeneration, compared with the recycled crumb rubber composite modified asphalt (9547.4 Pa), the rutting factor of the long-term aged bio-oil activated crumb rubber modified asphalt (9046.1 Pa) was further reduced by 5.3%. Its creep stiffness (52.1 MPa) was reduced by 9.4% compared with the recycled composite modified asphalt (57.5 MPa), and the creep rate (0.402) was increased by 3.9%. It shows that the activated bio-oil storage reservoir continuously releases light components during the aging process to achieve the dynamic self-compensation of the material performance. Moreover, the three-dimensional oil storage network formed by the gradient penetration of the bio-oil activated crumb rubber process has a long-term stress buffering function. Its regeneration effect comes from the self-healing mechanism inside the crumb rubber, rather than relying on the physical supplement of external regenerants. Particularly noteworthy is that the low-temperature performance indexes (S = 52.1, m = 0.402) of the bio-oil activated crumb rubber modified asphalt after aging are close to or even better than those of the regeneration system with 10% tall oil added (S = 57.5, m = 0.387) without adding any regenerants, which fully demonstrates the technical breakthrough of the integration of anti-aging and regeneration of the material through the in-situ reservoir effect by this process. Compared with the traditional regeneration technology, this process avoids the risk of high-temperature decomposition of the regenerant and the problem of secondary aging.

[0142] (6) Compare the performance differences between the ordinary crumb rubber modified asphalt (20%) and the bio-oil activated crumb rubber modified asphalt (30%).

[0143] Referring to the preparation methods, systems and processes provided in Example 1 and Example 2, the content of rubber powder is designed to be 30% of the mass of the base asphalt, the content of bio-oil is designed to be 10% of the mass of the base asphalt, the temperature inside the high-speed shear tank of the rubber powder modified asphalt is 160 °C, and the nitrogen pressurization time is 20 min.

[0144] Taking the ordinary rubber powder modified asphalt prepared with a rubber powder content designed to be 20% of the base asphalt by the process provided in Comparative Example 1 as a comparison. A temperature sweep test was carried out by a dynamic shear rheometer at 64 °C. The test process referred to AASHTO T 315, and the high and intermediate temperature viscoelastic properties of the asphalt were characterized by the rutting factor (G* / sinδ). The test results are shown in Table 12.

[0145] The creep stiffness (S) and creep rate (m) of the ordinary rubber powder modified asphalt and the bio-oil activated rubber powder modified asphalt were measured by the bending beam rheology test (BBR) at -18 °C to evaluate their low temperature performance. Among them, the S value characterizes the low temperature brittleness of the asphalt (the larger the S value, the harder and more brittle), and the m value reflects the stress dissipation ability (the larger the m value, the better the dissipation ability). The test results are shown in Table 12.

[0146] Table 12 Test results of rutting factor and BBR

[0147]

[0148] It is found from the experimental results in Table 12 that: the bio-oil activation process of the present invention still realizes the synergistic optimization of high and low temperature performances under the condition of high rubber powder content (30%). The rutting factor of the bio-oil activated rubber powder modified asphalt is increased by 2.6% compared with the ordinary rubber powder modified asphalt. The enhancement of its high temperature rutting resistance is due to the synergistic effect of the dense oil film layer formed by nitrogen pressurization and the three-dimensional network structure of the rubber powder, effectively improving the elastic recovery performance of the asphalt. Particularly noteworthy is that its creep stiffness (97.4 MPa) is reduced by 23.9% compared with the ordinary rubber powder system, and at the same time the creep rate is increased by 11.4%, proving that the bio-oil dynamic release mechanism effectively improves the flexibility of the rubber powder-asphalt interface.

[0149] In summary, different from the contradictory phenomenon in the traditional technology that the high rubber powder content leads to the improvement of high temperature performance and the deterioration of low temperature performance, the present invention breaks through and realizes the positive correlation improvement of the high and low temperature performances of the high rubber powder content modified asphalt through the synergistic mechanism of the in-situ reservoir effect of bio-oil and the inert interface modification of nitrogen, which can provide key technical support for the resource utilization of high proportion waste tire rubber powder.

[0150] Obviously, the above embodiments are merely examples given for clear illustration and not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or alterations can be made based on the above description. It is not necessary and impossible to exhaustively list all implementation manners here. And the obvious changes or alterations derived therefrom still fall within the protection scope of the present invention.

Claims

1. A preparation method of highly doped bio - oil activated rubber powder modified asphalt, characterized in that It includes the following steps: S1. Stir and mix the rubber powder and bio-oil at 110 ± 5 °C and under a negative pressure of -0.08 to -0.095 MPa for 45 to 60 minutes to promote the initial penetration of bio-oil into the rubber powder; then switch to nitrogen and pressurize to 0.3 to 0.5 MPa and stir and mix for 20 to 30 minutes to allow the bio-oil to fill the internal pores of the rubber powder, obtaining bio-oil activated rubber powder; The process of step S1 is carried out in a rubber powder pretreatment tank. The rubber powder pretreatment tank is equipped with a stirring device. The stirring device includes a rotary drive and rotary blades. The rotary blades are arranged in the tank body. The rotary blades adopt a three-layer combined blade configuration of upper, middle and lower layers. During operation, the rotary drive controls the rotation speeds of the three layers of blades respectively. The rotation speed of the upper layer of blades is 60 to 90 rpm, which is used to generate strong shear force to break the agglomeration of rubber powder; the rotation speed of the middle layer of blades is 30 to 60 rpm, which is used to promote radial diffusion; the rotation speed of the lower layer of blades is 15 to 30 rpm, which is used to enhance axial circulation and scrape the wall; at the same time, the rotary drive also controls the overall rotary blades to perform the following cyclic motion: rotate forward for 5 minutes, pause for 10 seconds, and then rotate backward for 3 minutes; S2. Add the bio-oil activated rubber powder of S1 into the hot matrix asphalt, control the temperature at 160 ± 5 °C, and control the shear speed at 2500 to 5500 rpm; shear and mix for 20 to 60 minutes to obtain bio-oil activated rubber powder modified asphalt; Based on the mass of the matrix asphalt, the rubber powder dosage is 20% to 35% of the matrix asphalt; the bio-oil dosage is 10% to 15% of the matrix asphalt.

2. A preparation method of a high-loading bio-oil activated rubber powder modified asphalt according to claim 1, characterized in that In S1, the nitrogen pressure is increased in a gradient manner to the preset pressure at a rate of 0.03 to 0.07 MPa / min.

3. The preparation method of a highly doped bio-oil activated crumb rubber modified asphalt according to claim 1, characterized in that, The bio-oil in step S1 is a renewable plant-based pyrolysis product rich in light component content prepared from agricultural and forestry waste rich in cellulose, hemicellulose and lignin. The agricultural and forestry waste includes corn straw, rice husk, wheat straw and wood chips.

4. The preparation method of a highly doped bio-oil activated crumb rubber modified asphalt according to claim 1, characterized in that, The rubber powder in step S1 is particulate matter obtained by mechanically crushing waste tires, or particulate matter obtained by normal temperature grinding of waste rubber conveyor belts or waste rubber seals. The particle size range of the particulate matter is controlled at 0.3 mm to 0.6 mm.

5. A production system for highly doped bio-oil activated crumb rubber modified asphalt capable of implementing the preparation method described in any one of claims 1 to 4, characterized in that, It includes a rubber powder pretreatment tank, a high-speed shear tank for rubber powder modified asphalt and a storage tank for rubber powder modified asphalt connected in sequence; The rubber powder pretreatment tank is connected to the high-speed shear tank for rubber powder modified asphalt through a bio-oil pretreated rubber powder conveyor, and the high-speed shear tank for rubber powder modified asphalt and the storage tank for rubber powder modified asphalt are connected through a rubber powder modified asphalt conveyor; It also includes a rubber powder conveying component, a biological oil pumping component, a nitrogen pressurizing component, and a vacuum pump component connected to the rubber powder pretreatment tank; the rubber powder conveying component is used to quantitatively convey rubber powder to the rubber powder pretreatment tank, the biological oil pumping component is used to quantitatively pump biological oil to the rubber powder pretreatment tank, the nitrogen pressurizing component is used to pressurize the rubber powder pretreatment tank with nitrogen, and the vacuum pump component is used to achieve the negative pressure condition of the rubber powder pretreatment tank; it also includes a hot asphalt conveying component, and the hot asphalt conveying component is used to convey hot base asphalt to the rubber powder modified asphalt high-speed shearing tank; The rubber powder pretreatment tank is provided with a temperature control device and a stirring device; the rubber powder modified asphalt high-speed shearing tank is also provided with a temperature control device and a stirring device; the rubber powder modified asphalt storage tank is also provided with a stirring device.

6. The production system of highly doped bio-oil activated rubber powder modified asphalt according to claim 5, characterized in that, The temperature control device of the rubber powder pretreatment tank includes a jacketed heat-conducting oil circulation heating device and a first PID temperature controller, which are used to control the temperature in the rubber powder pretreatment tank at 110±5°C; Its stirring device includes a rotary drive and rotary blades, and the rotary drive can drive the rotary blades to rotate and stir the materials in the tank; The rotary blades of the rubber powder pretreatment tank are arranged in the tank body, adopting a three-layer combined blade configuration of upper, middle and lower layers. The upper-layer blades adopt folded-blade type blades, the middle-layer blades adopt spiral ribbon type blades, and the lower-layer blades adopt anchor type blades. The gap between the outer edge of the anchor type blades and the tank wall is ≤5mm, and polytetrafluoroethylene or wear-resistant rubber scrapers are provided; the rotary drive is arranged on the top of the rubber powder pretreatment tank, and is used to control the rotation speed, rotation time and rotation direction of the rotary blades.

7. The production system of highly doped bio-oil activated rubber powder modified asphalt according to claim 5, characterized in that, The temperature control device of the rubber powder modified asphalt high-speed shearing tank includes a jacketed heat-conducting oil circulation heating device and a second PID temperature controller, which are used to control the temperature in the rubber powder modified asphalt high-speed shearing tank at 160±5°C; Its stirring device includes a high-speed shearing controller and a rotary high-speed shearing device. The high-speed shearing controller can drive the rotary high-speed shearing device to rotate and stir the materials in the tank and control the shearing speed and shearing time of the rotary high-speed shearing device; The stirring device of the rubber powder modified asphalt storage tank includes stirring blades and a stirring drive. The stirring blades are arranged in the rubber powder modified asphalt storage tank, and the stirring drive is arranged on the top of the rubber powder modified asphalt storage tank. The stirring drive is used to drive the stirring blades to rotate and stir the materials in the tank and control the stirring speed, rotation time and rotation direction of the stirring blades.

8. The production system of highly doped bio-oil activated rubber powder modified asphalt according to claim 5, characterized in that, The rubber powder conveying component includes a rubber powder storage box, a rubber powder conveying pipe, a fan, a spiral weighing scale and a first valve. The rubber powder conveying pipe connects the rubber powder storage box and the rubber powder pretreatment tank, and the first valve, the fan and the spiral weighing scale are sequentially arranged on the rubber powder conveying pipe; The bio-oil pumping component includes a bio-oil storage tank, a bio-oil delivery pipe, a metering pump, and a second valve. The bio-oil delivery pipe connects the bio-oil storage tank and the rubber powder pretreatment tank, and the second valve and the metering pump are sequentially arranged on the bio-oil delivery pipe; The nitrogen pressurization component includes a nitrogen tank, a nitrogen pressurization pipe, a third valve, a second pressure controller, and a pressurization pump. The nitrogen pressurization pipe is used to connect the nitrogen tank and the rubber powder pretreatment tank, and the third valve, the second pressure controller, and the pressurization pump are arranged on the nitrogen pressurization pipe; The pressurization pump is used to quickly fill the rubber powder pretreatment tank with nitrogen and pressurize it. The second pressure controller is used to control the pressure in the rubber powder pretreatment tank at 0.3 - 0.5 MPa. A pump suction type nitrogen concentration detector for detecting the nitrogen concentration in the nitrogen tank is provided at the bottom of the nitrogen tank; The vacuum pump component includes a vacuum pump, a vacuum pumping pipeline, a fourth valve, and a first pressure controller. The vacuum pump is connected to the bottom of the rubber powder pretreatment tank through the vacuum pumping pipeline, and the fourth valve and the first pressure controller are arranged on the vacuum pumping pipeline. The first pressure controller is electrically connected to the vacuum pump and is used to control the pressure in the rubber powder pretreatment tank at -0.08 - -0.095 MPa.

9. The production system of high-content bio-oil activated rubber powder modified asphalt according to claim 5, wherein The hot asphalt delivery component includes a hot asphalt storage tank, a hot asphalt delivery device, and a fifth valve. The hot asphalt delivery device connects the hot asphalt storage tank and the rubber powder modified asphalt high-speed shearing tank, and the fifth valve is arranged on the hot asphalt delivery device; A weight detector is provided at the bottom of the hot asphalt storage tank for controlling the mass of the hot asphalt added to the rubber powder modified asphalt high-speed shearing tank. A microwave heating device is installed in the body of the hot asphalt storage tank for controlling the temperature in the hot asphalt storage tank at 150 ± 10 °C.

10. A high-content bio-oil activated rubber powder modified asphalt prepared by the preparation method according to any one of claims 1 - 4 or the production system according to any one of claims 5 - 9.

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