Preparation method of warm-mixed modified asphalt based on coal liquefaction oil residues

Abstract

The invention relates to the field of asphalt production, and particularly discloses a preparation method of warm-mixed modified asphalt based on coal liquefaction oil residues, which comprises the following steps: S1, raw material pretreatment: pre-crushing the coal liquefaction oil residues until the particle size is less than or equal to 5mm, then refining the coal liquefaction oil residues to 200 meshes through an airflow mill, and then drying and dehydrating the coal liquefaction oil residues; the preparation method comprises the following steps: freezing SBS in a liquid nitrogen environment of-30 DEG C, and crushing the frozen SBS into 0.5-1mm particles by a hammer crusher; s2, pre-mixing the composite modifier by stages: in the first stage, adding the coal liquefaction oil residue, the aromatic oil and the rubber powder into a high-speed stirrer at 80 DEG C, and stirring; according to the preparation method of the warm-mixed modified asphalt based on the coal liquefaction oil residues, through the coal liquefaction oil residue superfine activation and SBS cryogenic grinding technology, the interfacial activity of the raw materials is improved, solid waste resource utilization is achieved, the modification cost is reduced, and meanwhile, by combining staged temperature control mixing and dissolving with the ultrasonic-assisted dispersion technology, the warm-mixed modified asphalt is prepared. The high-temperature rutting resistance and the water stability of the composite modified asphalt are improved.

Description

Technical Field

[0001] The present invention relates to the field of asphalt production, and particularly to a preparation method of warm mix modified asphalt based on coal liquefaction oil residue. Background Art

[0002] Asphalt pavement is the most important pavement form in China. With the expansion of domestic road construction and the rapid increase in traffic volume, as well as the continuous increase in heavy and large vehicles, the performance requirements for road asphalt are getting higher and higher. Composite modified asphalt has been widely used due to its excellent performance indicators.

[0003] Currently, road modified asphalt relies on high-temperature melting (180 - 190 °C) to blend SBS with coarse-grained coal liquefaction oil residue (DCLR, 80 - 100 mesh, specific surface area ≤ 1.5 m² / g). Although its low dosage can improve high-temperature performance, the coarse particle size leads to weak interfacial bonding and easy phase separation, and ultra-high temperature processing exacerbates asphalt thermal aging and the loss of warm mix agent activity; in addition, the static development process results in poor storage stability, and the utilization rate of coal tar solid waste is relatively low, and the contradiction between cost and environmental protection is prominent.

[0004] Therefore, it is necessary to propose a preparation method of warm mix modified asphalt based on coal liquefaction oil residue to solve the above problems. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to overcome the defects existing in the prior art. The present invention proposes a preparation method of warm mix modified asphalt based on coal liquefaction oil residue, which solves the problems existing in the prior art in the background art.

[0006] To achieve the above object, the technical solution adopted by the present invention is as follows: A preparation method of warm mix modified asphalt based on coal liquefaction oil residue, comprising the following steps: S1: Raw material pretreatment. The coal liquefaction oil residue is pre-crushed to a particle size ≤ 5 mm, then refined to 200 mesh by a jet mill, and then subjected to drying and dehydration treatment; The SBS is frozen in a -30 °C liquid nitrogen environment and crushed into 0.5 - 1 mm particles by a hammer mill; S2: Staged premixing of composite modifiers: In the first stage, the coal liquefaction oil residue, aromatic oil, and rubber powder are added to a high-speed mixer and stirred at 80 °C; In the second stage, the temperature is raised to 160 °C, and SBS and a stabilizer are added and stirred until completely melted; S3: Heat the petroleum asphalt to 170 °C in a pulsed ultrasonic shear reactor, add a warm mix agent and perform shearing and turn on the ultrasonic wave; S4: Slowly add the premixed composite modifier into the pulsed ultrasonic shearing reactor, maintain shearing at 170 °C and enable ultrasonic assistance to obtain a high-viscosity liquid product; S5: Transfer the high-viscosity liquid product to a dynamic development device for constant-temperature development at 160 °C. The specific development steps include: S51: Add the high-viscosity liquid product from the upper feed port of the dynamic development device to the inner periphery of the top of the centrifugal spreading disk inside the development device. The driving mechanism drives the centrifugal spreading disk to rotate. Under the action of centrifugal force, the high-viscosity liquid is evenly spread into a thin layer. Pass 160 °C hot air into the inside of the centrifugal spreading disk to heat the high-viscosity liquid, and generate oscillation on the centrifugal spreading disk through a magnetic vibrator; S52: The material thrown to the periphery of the centrifugal spreading disk by centrifugal force falls from the edge, and then continues to be conveyed to the inner periphery of the top of the centrifugal spreading disk through the spiral conveying component at the lower end of the centrifugal spreading disk for continuous centrifugal spreading and heating.

[0007] Preferably, in the raw material pretreatment stage, when the coal liquefaction oil residue refined by a jet mill is dried and dehydrated, it is specifically dried in a vacuum oven at 120 °C for 4 hours.

[0008] Preferably, in the raw material pretreatment stage, the SBS particles crushed by a hammer mill are stored in a vacuum seal at -20 °C.

[0009] Preferably, in the stage of staged premixing of the composite modifier, the mass percentages of coal liquefaction oil residue, aromatic oil, rubber powder, SBS, and stabilizer are 5%, 4%, 10%, 6%, and 0.15% respectively.

[0010] Preferably, the warm mix additive is a fatty acid amide-based warm mix additive, and the proportion is 5%.

[0011] Preferably, the dynamic development device includes an oven. The upper inner side of the oven is provided with a centrifugal spreading disk. The bottom of the centrifugal spreading disk is evenly surrounded by an electromagnetic vibrator. One side of the upper end of the oven is provided with a feed port, and one end of the feed port corresponds to the inner periphery of the top of the centrifugal spreading disk; A driving mechanism for driving the centrifugal spreading disk to rotate is provided at the upper end of the centrifugal spreading disk. The driving mechanism includes a rotating shaft that penetrates through the middle of the centrifugal spreading disk and has a hollow structure. A driven wheel is provided at the upper end of the rotating shaft. A driving source is provided on one side of the upper end of the oven. The output end of the driving source is provided with a driving wheel that is driven by the driving source to rotate and meshes with the driven wheel. The centrifugal spreading disk is connected to the side wall of the rotating shaft through a pipeline component; A cavity is provided inside the centrifugal spreading disk. The pipeline component is communicated with the rotating shaft and the cavity. The bottom of the rotating shaft is rotatably provided with a hot air supply pipe that extends to the outside of the oven for supplying hot air, and the hot air supply pipe is communicated with the lower end of the rotating shaft.

[0012] Preferably, the pipeline assembly includes a first connecting pipe disposed around the outer periphery of the top of the centrifugal spreading plate and a second connecting pipe disposed around the inner periphery of the top of the centrifugal spreading plate. The ends of the first connecting pipe and the second connecting pipe away from the centrifugal spreading plate are both communicated with the rotating shaft, and the upper end of the second connecting pipe is lower than the upper end of the first connecting pipe. A blocking block is disposed inside the rotating shaft between the upper ends of the first connecting pipe and the second connecting pipe.

[0013] Preferably, a spiral conveying assembly is disposed at the lower end of the centrifugal spreading plate. The spiral conveying assembly includes spiral blades disposed on the outer wall of the lower end of the rotating shaft. A first through hole corresponding to the upper end of the spiral blades is disposed in the middle of the centrifugal spreading plate. A feeding cylinder located outside the spiral blades is fixed to the inner wall of the lower end of the oven, and the upper end of the feeding cylinder extends to the inside of the first through hole and is movably connected to the first through hole.

[0014] Preferably, the spiral blades are of a hollow structure, and second through holes communicating with the inside of the spiral blades are disposed on the inner walls of the upper and lower ends of the spiral blades, and the spiral blades are communicated with the rotating shaft through the second through holes.

[0015] Preferably, a hollow power disk is disposed at the upper end of the rotating shaft. Power nozzles are evenly arranged around the tangential side of the power disk. A top cover is disposed at the upper end of the oven. The power disk is located inside the top cover, and an exhaust port is disposed on one side of the top cover.

[0016] Compared with the prior art, the beneficial effects of the present invention include: 1. In the preparation method of warm mix modified asphalt based on coal liquefaction oil residue, through the ultra-fine activation of coal liquefaction oil residue and SBS cryogenic pulverization technology, the interfacial activity of raw materials is improved, the resource utilization of solid waste is realized, the modification cost is reduced. At the same time, the temperature control and mixing in stages combined with the ultrasonic assisted dispersion process improve the high temperature rutting resistance and water stability of the composite modified asphalt.

[0017] 2. In the preparation method of warm mix modified asphalt based on coal liquefaction oil residue, through the rotatable centrifugal spreading plate disposed in the dynamic development device, the material can be evenly spread into a thin layer, which can not only reduce caking and agglomeration phenomena, but also make the heat transfer faster and the heating more uniform, significantly reducing the internal temperature difference of the material, avoiding local overheating or under-temperature, with a larger processing capacity in the same time and significantly improved production efficiency. In addition, the centrifugal force promotes the gradient distribution of coal liquefaction oil residue nanoparticles in the asphalt phase, increasing the molecular contact opportunity, making the modifier easier to be evenly mixed. Combined with the dynamic oscillation of the electromagnetic vibrator, the three-dimensional network construction of SBS molecular chains can be completed at a low temperature of 160°C, reducing VOC emissions, and at the same time consuming coal liquefaction oil residue solid waste, promoting the low-carbon transformation of road materials. Description of the Drawings

[0018] The disclosure of the present invention will be described with reference to the accompanying drawings. It should be understood that the drawings are for illustrative purposes only 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. Among them: Figure 1 Schematically shows the process flow diagram of the present invention; Figure 2 Schematically shows the structural schematic diagram of the dynamic development device of the present invention; Figure 3 Schematically shows the structural schematic diagram inside the oven of the present invention; Figure 4 Schematically shows the structural schematic diagram of the feeding cylinder and the rotating shaft of the present invention in a disassembled state; Figure 5 Schematically shows the structural schematic diagram of the bottom view of the centrifugal spreading plate of the present invention; Figure 6 Schematically shows the cross-sectional structural schematic diagram of the connection between the centrifugal spreading plate and the rotating shaft of the present invention; Figure 7 Schematically shows the structural schematic diagram of the spiral blade of the present invention.

[0019] Reference numerals in the figure: 1, oven; 2, feed inlet; 3, discharge port; 4, top cover; 5, exhaust port; 6, on-line rheometer probe; 7, hot gas supply pipe; 8, drive source; 9, conductive slip ring; 10, feeding cylinder; 11, centrifugal spreading plate; 12, first connecting pipe; 13, fixing bracket; 14, rotating shaft; 15, spiral blade; 16, driven wheel; 17, driving wheel; 18, power disk; 19, power nozzle; 20, second connecting pipe; 21, electromagnetic vibrator; 22, first through hole; 23, cavity; 24, plug; 25, second through hole. Detailed embodiments

[0020] It is easy to understand that according to the technical solution of the present invention, without changing the essence of the present invention, those of ordinary skill in the art can propose various interchangeable structural forms and implementation methods. Therefore, the following detailed embodiments and the accompanying drawings are only illustrative descriptions of the technical solution of the present invention, and should not be regarded as the whole of the present invention or as a limitation or restriction on the technical solution of the present invention.

[0021] According to an embodiment of the present invention in combination with Figures 1-7 Shown.

[0022] As Figure 1 Shown, a method for preparing warm mix modified asphalt based on coal liquefaction oil residue includes the following steps: Step 1: Pretreatment of raw materials. The coal liquefaction residue (DCLR) is pre-crushed by a jaw crusher to a particle size of ≤5 mm, and then refined to 200 mesh by a jet mill at a pressure of 0.8 MPa for 15 minutes. Ultrafine crushing to 200 mesh by the jet mill significantly increases the specific surface area and enhances the interfacial bonding with asphalt. Then it is dried in a vacuum oven at 120 °C for 4 hours. Compared with conventional atmospheric drying, it can reduce thermal oxidation side reactions and retain active components; Table 1 below shows the comparative examples of the DCLR crushing particle size experiment: Table 1

[0023] As can be seen from Table 1, the specific surface area of the coal liquefaction residue is increased to 3.5 m² / g after crushing to 200 mesh, a 94% increase compared to 100 mesh. The interfacial bonding strength reaches 18 MPa, doubling that of 100 mesh, and the support dosage is increased to 5%. Although the dosage can reach 6.5% after crushing to 300 mesh, its energy consumption surges to 150 kWh / t, and nanoscale dispersion requires high-cost stabilizers. Considering the comprehensive solid waste disposal target and cost, 200 mesh is the preferred choice.

[0024] Table 2 below shows the comparative examples of the drying process experiment: Table 2

[0025] As can be seen from Table 2, vacuum drying at 120 °C reduces thermal oxidation loss compared to the atmospheric pressure process at 150 °C, and the asphaltene retention rate is increased by 13%. Moreover, the segregation index after 180 days of storage is only 0.03, meeting the high-quality industry standard. Compared with vacuum drying at 100 °C, the drying time is shortened by 50% and the energy consumption is reduced by 20%. Although the moisture content is slightly higher, it is still within the allowable range of modified asphalt. Therefore, 120 °C vacuum drying is preferred.

[0026] SBS is frozen in a -30 °C liquid nitrogen environment and crushed into 0.5 - 1 mm particles by a hammer mill. Specifically, the SBS raw material is immersed in liquid nitrogen at -30 °C for 10 minutes to achieve deep embrittlement, and then quickly transferred to the hammer mill for low-temperature crushing. The particle size is controlled to 0.5 - 1 mm by a 1 mm / 0.5 mm grading screen. The environment below -15 °C is maintained throughout the process to avoid temperature rise and agglomeration. After crushing, the particles are vacuum-sealed and stored at -20 °C to achieve low-damage crushing of molecular chains, with the specific surface area increased to 0.8 - 1.2 m² / g and the melting dispersion efficiency improved; It should be noted that SBS is a styrene-butadiene-styrene block copolymer, which belongs to a commonly used thermoplastic elastomer material. Its main function is to endow asphalt with elastic recovery ability similar to that of rubber, reduce the risk of cracking, improve high-temperature stability and low-temperature anti-brittle cracking property, and enhance anti-aging and anti-fatigue properties. In this step, SBS is processed by cryogenic grinding with liquid nitrogen and made into 0.5-1 mm particles through cryogenic embrittlement and low-temperature crushing. This not only maintains the molecular chain structure of the material but also increases the specific surface area, improving the subsequent melting and mixing efficiency and ultimately enhancing the comprehensive mechanical properties of asphalt. Specifically, it is carried out by a liquid nitrogen cryogenic grinder, which belongs to the prior art and the specific principle will not be elaborated too much; The following Table 3 is the experimental comparative example of the SBS pretreatment process: Table 3

[0027] As can be seen from Table 3, freezing at -30°C makes SBS below the glass transition temperature. The hammering stress is concentrated at the embrittlement point, the molecular chain fracture rate drops from 25% to 5%, and the elastic recovery rate increases by 40%. The specific surface area of 0.5-1 mm particles is 4 times higher than that of 2-5 mm particles, and the subsequent melting and dispersion time is shortened from 90 min to 30 min. Therefore, freezing in a -30°C liquid nitrogen environment and crushing to 0.5-1 mm particles by a hammer mill is the preferred scheme.

[0028] Step 2: Staged premixing of the composite modifier: In the first stage, 5% by mass of DCLR, 4% by mass of aromatic oil, and 10% by mass of rubber powder are added to a high-speed mixer at 80°C and stirred at 300 rpm for 15 min. The high-speed mixer is a two-stage temperature-controlled high-speed mixer, which uses existing known equipment and the specific principle will not be elaborated too much. In the second stage, the temperature is raised to 160°C, 6% by mass of SBS and 0.15% by mass of stabilizer are added, and it is stirred at 500 rpm for 30 min until completely melted. In this step, a two-stage design of low-temperature premixing and high-temperature melting is adopted. In the first stage, DCLR, aromatic oil, and rubber powder are mixed at 80°C to avoid cross-linking of rubber powder at high temperature. In the second stage, the temperature is raised to 160°C and SBS and stabilizer are added to achieve step-by-step activation of the modifier.

[0029] Step 3: Preheating of asphalt. The petroleum asphalt is heated to 170°C in a pulsed ultrasonic shear reactor and 5% fatty acid amide warm mix agent is added for shearing, specifically shearing at 1500 rpm for 10 min. Modifier blending: Slowly add the premixed composite modifier into the pulsed ultrasonic shear reactor, maintain the shear at 170 °C for 30 min, and turn on the ultrasonic assistance in the first 15 min to obtain a high-viscosity liquid product. During the modifier blending step, introduce 20 kHz ultrasonic waves to generate cavitation effects to break up SBS aggregates, which can improve the dispersion efficiency compared with traditional pure mechanical shearing. The pulse period of the ultrasonic wave is 5 s on / 3 s off; Table 4 below shows the comparative examples of the ultrasonic assistance effect experiment: Table 4

[0030] As can be seen from Table 4, the 20 kHz pulsed ultrasound achieves a 98% SBS dispersion efficiency through cavitation effects, which is 36% higher than that without ultrasound. The interfacial binding energy is increased to 52 J / m², and the temperature rise ΔT ≤ 3 °C to avoid thermal damage. Although the dispersion efficiency of 40 kHz continuous ultrasound reaches 95%, the energy consumption doubles. Therefore, pulsed ultrasound is the preferred option.

[0031] Step 5: Transfer the high-viscosity liquid product into the dynamic development device and keep it at a constant temperature of 160 °C for development. The specific development principle is as follows: Add the high-viscosity liquid product from the upper feed port 2 of the dynamic development device to the inner periphery of the top of the centrifugal spreading plate 11 inside the development device. The driving mechanism drives the centrifugal spreading plate 11 to rotate. Under the action of centrifugal force, the high-viscosity liquid is evenly spread into a thin layer. Pass 160 °C hot air into the inside of the centrifugal spreading plate 11 to heat the high-viscosity liquid, and generate oscillations on the centrifugal spreading plate 11 through the electromagnetic vibrator 21. The material thrown to the periphery of the centrifugal spreading plate 11 by centrifugal force falls from the edge, and then continues to be transported to the inner periphery of the top of the centrifugal spreading plate 11 through the spiral conveying component at the lower end of the centrifugal spreading plate 11 for continuous centrifugal spreading and heating. During this period, the complex shear modulus is monitored in real time by the on-line rheometer probe 6, and the development is terminated when the target value is reached.

[0032] During the development stage, the dynamic oscillation of the rotating centrifugal spreading plate 11 superimposed with the electromagnetic vibrator 21 is adopted to induce the three-dimensional network reconstruction of SBS molecular chains through periodic stress, and at the same time, the on-line rheometer is integrated to monitor the complex shear modulus in real time to realize the intelligent judgment of the development end point; For this process, the highest temperature in the whole process is controlled at 170 °C, which is 20 - 30 °C lower than the traditional process. And the dynamic oscillation compensates for the insufficient development caused by low temperature, and can also reduce the emission of volatile organic compounds (VOCs), meeting the requirements of green construction.

[0033] Further, as Figures 2-7As shown in the figure, the dynamic development device specifically includes an oven 1. At the upper end inside the oven 1, there is a centrifugal spreading plate 11. At the bottom of the centrifugal spreading plate 11, electromagnetic vibrators 21 are evenly arranged in a circular manner. The wires of the electromagnetic vibrators 21 can extend upward through the inside of the rotating shaft 14. And at the top end of the rotating shaft 14, there is a conductive slip ring 9. The leads of the electromagnetic vibrators 21 are electrically connected to the conductive slip ring 9. The conductive slip ring 9 is externally connected to a power source, so as not to affect rotation. Moreover, in order to adapt to high temperatures, a heat-insulating protective sleeve can be arranged outside the wires of the electromagnetic vibrators 21 for protection, which can adapt to the high temperature inside the oven 1. The heat-insulating protective sleeve adopts conventional technical means and will not be elaborated too much. On one side of the upper end of the oven 1, there is a feed inlet 2, and one end of the feed inlet 2 corresponds to the inner periphery of the top of the centrifugal spreading plate 11. At the bottom of the oven 1, there is a discharge port 3 for discharging materials. An in-line rheometer probe 6 penetrates through the side wall of the oven 1. The inner end of the in-line rheometer probe 6 is used to contact the materials inside the oven 1. At the upper end of the centrifugal spreading plate 11, there is a driving mechanism for driving the centrifugal spreading plate 11 to rotate. The driving mechanism includes a rotating shaft 14 that penetrates through the middle of the centrifugal spreading plate 11 and has a hollow structure. The upper end of the rotating shaft 14 extends to the top of the oven 1. At the upper end of the rotating shaft 14, there is a driven wheel 16. On one side of the upper end of the oven 1, there is a driving source 8. The driving source 8 is preferably a reduction motor. At the output end of the driving source 8, there is a driving wheel 17 that is driven by the driving source 8 to rotate and meshes with the driven wheel 16. Between the side walls of the centrifugal spreading plate 11 and the rotating shaft 14, they are connected through a pipeline assembly. The pipeline assembly includes a first connecting pipe 12 arranged at the outer periphery of the top of the centrifugal spreading plate 11 and a second connecting pipe 20 arranged at the inner periphery of the top of the centrifugal spreading plate 11. And the ends of the first connecting pipe 12 and the second connecting pipe 20 far from the centrifugal spreading plate 11 are both communicated with the rotating shaft 14, and the upper end of the second connecting pipe 20 is lower than the upper end of the first connecting pipe 12; In order to supply hot air to heat the materials, a cavity 23 is arranged inside the centrifugal spreading plate 11. The pipeline assembly is communicated with the rotating shaft 14 and the cavity 23. At the bottom of the rotating shaft 14, there is a hot air supply pipe 7 that extends to the outside of the oven 1 for supplying hot air, and the hot air supply pipe 7 is communicated with the lower end of the rotating shaft 14. In order to enable the hot air to enter the second connecting pipe 20, the cavity 23, and the first connecting pipe 12 in sequence, a blocking block 24 is arranged inside the rotating shaft 14 between the upper ends of the first connecting pipe 12 and the second connecting pipe 20.

[0034] In order to achieve the cyclic paving and heating of materials, a spiral conveying assembly is provided at the lower end of the centrifugal paving disc 11. The spiral conveying assembly includes a spiral blade 15 disposed on the outer wall of the lower end of the rotating shaft 14. A first through hole 22 corresponding to the upper end of the spiral blade 15 is provided in the middle of the centrifugal paving disc 11. A feeding cylinder 10 located outside the spiral blade 15 is provided at the lower end of the oven 1, and the upper end of the feeding cylinder 10 extends to the inside of the first through hole 22 and is movably connected to the first through hole 22. Specifically, a fixing bracket 13 is provided on the side wall of the feeding cylinder 10, and the other end of the fixing bracket 13 is fixed to the inner wall of the oven 1.

[0035] In order to enable uniform heating during the conveying stage of the spiral blade 15, the spiral blade 15 is provided with a hollow structure, and second through holes 25 communicating with the inside of the spiral blade 15 are provided on the inner walls of the upper and lower ends of the spiral blade 15, and the spiral blade 15 communicates with the rotating shaft 14 through the second through holes 25.

[0036] In addition, in order to reduce the energy consumption of the drive source 8, a hollow power disc 18 is provided at the upper end of the rotating shaft 14. Power nozzles 19 are uniformly arranged around the tangential side of the power disc 18. A top cover 4 is provided at the upper end of the oven 1. The power disc 18 is located inside the top cover 4. An exhaust port 5 is provided on one side of the top cover 4. The drive source 8 is installed at the upper end of the top cover 4.

[0037] The specific working principle of the dynamic development device is as follows: During use, the high-viscosity liquid product obtained by shearing in the pulsed ultrasonic shearing reactor is introduced into the inner periphery at the top of the centrifugal spreading disk 11 through the feed port 2. During this period, the driving source 8 drives the driving wheel 17 to rotate. The driving wheel 17 drives the rotating shaft 14 to rotate through the driven wheel 16. The rotating shaft 14 drives the centrifugal spreading disk 11 to rotate through the second connecting pipe 20 and the first connecting pipe 12, and the spiral blade 15 rotates synchronously. Due to the rotation of the centrifugal spreading disk 11, the material entering from the feed port 2 can evenly fall on the top of the centrifugal spreading disk 11 in a surrounding manner. Under the action of the rotation of the centrifugal spreading disk 11, the material generates centrifugal force, which can evenly spread the material into a thin layer. The hot gas supply pipe 7 is externally connected to a heat source to supply hot gas at about 160 °C to the inside of the rotating shaft 14. The hot gas enters the inside of the rotating shaft 14 through the hot gas supply pipe 7. Part of the hot gas will enter the inside of the spiral blade 15 through the second through hole 25 at the lower end of the spiral blade 15, and the remaining hot gas directly rises along the inside of the rotating shaft 14 and enters the inside of the spiral blade 15. The hot gas entering the inside of the spiral blade 15 will return to the inside of the rotating shaft 14 through the second through hole 25 at the upper end of the spiral blade 15 to be aggregated with the other part of the hot gas, and then enter the second connecting pipe 20 under the blockage of the block 24, enter the centrifugal spreading disk 11 through the second connecting pipe 20. The centrifugal spreading disk 11 conducts heat, and the hot gas heats the centrifugal spreading disk 11, so that the centrifugal spreading disk 11 heats the material. Then the hot gas enters the upper end inside of the rotating shaft 14 through the first connecting pipe 12 and finally discharges from the upper end of the rotating shaft 14. The material on the top of the centrifugal spreading disk 11 will gradually be thrown off from the edge, and then be conveyed upward by the rotation of the spiral blade 15. The material contacts the surface of the spiral blade 15 and is evenly heated and dried again by the spiral blade 15, and then returns to the top of the centrifugal spreading disk 11, and so on. During this period, the electromagnetic vibrator 21 generates oscillation on the centrifugal spreading disk 11. During this period, the complex shear modulus is monitored in real time by the on-line rheometer probe 6. When the target value is reached, the development is terminated, and the rotating shaft 14 rotates in reverse for discharging. The rotating centrifugal spreading disk 11 cooperates with the dynamic oscillation of the electromagnetic vibrator 21 and the on-line rheological monitoring, so that the modified asphalt can form a stable three-dimensional network structure at a low temperature of 160 °C, reducing the processing temperature by 20-30 °C compared with the traditional process, saving energy consumption, and at the same time ensuring that the complex shear modulus reaches more than 2.0 kPa, significantly improving the high-temperature rutting resistance and low-temperature cracking resistance; It should be noted that the hot gas discharged from the upper end of the rotating shaft 14 is tangentially discharged from the power nozzle 19. The reaction torque of the power nozzle 19 is in the same direction as the driving direction of the driving source 8, directly reducing the output torque requirement of the motor, indirectly reducing the power consumption and current, making the motor operation more efficient and easy, and being beneficial to energy saving.

[0038] The technical scope of the present invention is not limited to the content described above. Those skilled in the art can make various deformations and modifications to the above embodiments without departing from the technical idea of the present invention, and these deformations and modifications should all fall within the protection scope of the present invention.

Claims

1. A method for preparing warm-mix modified asphalt based on coal liquefaction oil residue, characterized in that: The following steps are involved: S1: Raw material pretreatment, pre-crushing the coal liquefaction oil residue to a particle size of ≤5mm, then grinding it to 200 mesh by air flow grinding, and then drying and dehydrating it; The SBS was frozen in liquid nitrogen at -30°C and crushed into 0.5-1 mm particles using a hammer mill; S2: Premixing of composite modifiers in stages: In the first stage, coal liquefaction oil residue, aromatic oil and rubber powder are added into a high-speed mixer and stirred at 80°C; In the second stage, the temperature is raised to 160°C, SBS and stabilizer are added, and stirred until completely melted; S3: heating the petroleum asphalt to 170°C in a pulse ultrasonic shear reactor, adding a warm mixing agent for shearing; S4: slowly add the premixed composite modifier into the pulse ultrasonic shear reactor, maintain shearing at 170°C and enable ultrasonic assistance to obtain a high-viscosity liquid product; S5: The high-viscosity liquid product is transferred to a dynamic development device for constant temperature development at 160°C. The specific development steps include: S51: adding the high-viscosity liquid product from the feed port at the upper end of the dynamic development device to the inner periphery of the top of the centrifugal spreading disk inside the development device, the driving mechanism drives the centrifugal spreading disk to rotate, and the high-viscosity liquid is evenly spread into a thin layer under the action of centrifugal force, and 160° C. hot air is introduced into the inside of the centrifugal spreading disk to heat the high-viscosity liquid, and the centrifugal spreading disk is vibrated by a magnetic vibrator; S52: The material thrown to the periphery of the centrifugal paving disk by the centrifugal force falls from the edge, and then is transported to the inner periphery of the top of the centrifugal paving disk through the spiral conveying assembly at the lower end of the centrifugal paving disk, and continues to be centrifugally paved and heated.

2. The method for preparing warm-mix modified asphalt based on coal liquefaction oil residue according to claim 1, characterized in that: In the raw material pretreatment stage, the coal liquefaction oil residue that has been finely ground by air flow is dried and dehydrated by drying in a vacuum oven at 120° C. for 4 hours.

3. The method for preparing warm-mix modified asphalt based on coal liquefaction oil residue according to claim 1, characterized in that: During the raw material pretreatment stage, the SBS particles crushed by a hammer mill were vacuum sealed and stored at -20°C.

4. The method for preparing warm-mix modified asphalt based on coal liquefaction oil residue according to claim 1, characterized in that: In the stage of premixing the composite modifier in stages, the mass percentages of coal liquefaction oil residue, aromatic oil, rubber powder, SBS and stabilizer are 5%, 4%, 10%, 6% and 0.15%, respectively.

5. The method for preparing warm-mix modified asphalt based on coal liquefaction oil residue according to claim 1, characterized in that: The warm mix agent is a fatty acid amide warm mix agent, accounting for 5%.

6. A method for preparing warm-mix modified asphalt based on coal liquefaction oil residue according to any one of claims 1 to 5, characterized in that: The dynamic development device comprises an oven, a centrifugal spreading disc is arranged at the inner upper end of the oven, an electromagnetic vibrator is evenly arranged around the bottom of the centrifugal spreading disc, a feed port is arranged on one side of the upper end of the oven, and one end of the feed port corresponds to the inner periphery of the top of the centrifugal spreading disc; The upper end of the centrifugal paving disc is provided with a driving mechanism for driving the centrifugal paving disc to rotate, the driving mechanism comprises a rotating shaft which is provided through the middle of the centrifugal paving disc and has a hollow structure, the upper end of the rotating shaft is provided with a driven wheel, a driving source is provided on one side of the upper end of the oven, an output end of the driving source is provided with a driving wheel which is driven to rotate by the driving source and meshes with the driven wheel, and the centrifugal paving disc is connected to the side wall of the rotating shaft through a pipeline assembly; A cavity is provided inside the centrifugal spreading disc, the pipeline assembly is connected with the rotating shaft and the cavity, a hot air supply pipe extending to the outside of the oven for supplying hot air is rotatably provided at the bottom of the rotating shaft, and the hot air supply pipe is connected with the lower end of the rotating shaft.

7. The method for preparing warm-mix modified asphalt based on coal liquefaction oil residue according to claim 6, characterized in that: The pipeline assembly includes a first connecting pipe arranged on the periphery of the top of the centrifugal paving disk and a second connecting pipe arranged on the inner periphery of the top of the centrifugal paving disk, and the ends of the first connecting pipe and the second connecting pipe away from the centrifugal paving disk are both connected to the rotating shaft, and the upper end of the second connecting pipe is lower than the upper end of the first connecting pipe; A blocking block is arranged on the inner side of the rotating shaft and is located between the upper ends of the first connecting pipe and the second connecting pipe.

8. The method for preparing warm-mix modified asphalt based on coal liquefaction oil residue according to claim 6, characterized in that: A spiral conveying assembly is arranged at the lower end of the centrifugal spreading disc, and the spiral conveying assembly includes a spiral blade arranged on the outer wall of the lower end of the rotating shaft, and a first through hole corresponding to the upper end of the spiral blade is arranged in the middle of the centrifugal spreading disc, and a feeding cylinder located outside the spiral blade is fixed to the inner wall of the lower end of the oven, and the upper end of the feeding cylinder extends to the inner side of the first through hole and is movably connected with the first through hole.

9. The method for preparing warm-mix modified asphalt based on coal liquefaction oil residue according to claim 8, characterized in that: The spiral blade is a hollow structure, and the inner walls at the upper and lower ends of the spiral blade are both provided with second through holes communicating with the interior of the spiral blade, and the spiral blade is communicated with the rotating shaft through the second through holes.

10. The method for preparing warm-mix modified asphalt based on coal liquefaction oil residue according to claim 7, characterized in that: A hollow power disc is arranged at the upper end of the rotating shaft, and power nozzles are evenly arranged around the tangential sides of the power disc. A top cover is arranged at the upper end of the oven, and the power disc is located inside the top cover. An exhaust port is arranged on one side of the top cover.

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