A method for preparing warm-mix modified asphalt based on coal liquefaction oil residue

Abstract

The present invention relates to the field of asphalt production, and specifically discloses a method for preparing warm-mix modified asphalt based on coal liquefaction oil residue, comprising the following steps: S1: raw material pretreatment, pre-crushing the coal liquefaction oil residue to a particle size of ≤5mm, then finely grinding it to 200 mesh by air flow milling, and then drying and dehydrating it; freezing SBS in a -30°C liquid nitrogen environment and crushing it to 0.5-1mm particles by a hammer mill; S2: premixing a composite modifier in stages: in the first stage, coal liquefaction oil residue, aromatic oil, and rubber powder are added to a high-speed mixer and stirred at 80°C. This method for preparing warm-mix modified asphalt based on coal liquefaction oil residue, through ultrafine activation of coal liquefaction oil residue and SBS freeze-crushing technology, improves the raw material interfacial activity, realizes solid waste resource utilization, and reduces modification costs. At the same time, the staged temperature-controlled miscibility combined with an ultrasonic-assisted dispersion process improves the high-temperature rutting resistance and water stability of the composite modified asphalt.

Description

Technical Field

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

[0002] Asphalt pavement is the most important pavement type in my country. With the expansion of domestic road construction and the rapid increase in traffic volume, the increasing number of heavy and large vehicles has led to increasingly demanding performance requirements for road asphalt. Composite modified asphalt is widely used due to its excellent performance indicators.

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

[0004] Therefore, it is necessary to propose a method for preparing 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 of the existing technology. The present invention proposes a method for preparing warm-mix modified asphalt based on coal liquefaction oil residue, which solves the problems of the existing technology in the background technology.

[0006] To achieve the above object, the technical solution adopted by the present invention is:

[0007] A method for preparing warm-mix modified asphalt based on coal liquefaction oil residue comprises the following steps:

[0008] 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 milling, and then drying and dehydrating it;

[0009] The SBS was frozen in liquid nitrogen at -30°C and crushed into 0.5-1 mm particles using a hammer mill;

[0010] S2: Premixing of composite modifiers in stages:

[0011] In the first stage, coal liquefaction oil residue, aromatic oil and rubber powder were added into a high-speed mixer and stirred at 80°C;

[0012] In the second stage, the temperature is raised to 160°C, SBS and stabilizer are added, and stirred until completely melted;

[0013] S3: Heating the petroleum asphalt to 170°C in a pulse ultrasonic shear reactor, adding a warm mix agent for shearing, and turning on the ultrasonic wave;

[0014] S4: Slowly add the premixed composite modifier into the pulse ultrasonic shear reactor, maintain the shear temperature at 170°C and enable ultrasonic assistance to obtain a high-viscosity liquid product;

[0015] S5: The high-viscosity liquid product is transferred to a dynamic growth device for growth at a constant temperature of 160°C. The specific growth steps include:

[0016] S51: A high-viscosity liquid product is added 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. Under the action of centrifugal force, the high-viscosity liquid is evenly spread into a thin layer. 160°C hot air is introduced into the centrifugal spreading disk to heat the high-viscosity liquid, and the centrifugal spreading disk is vibrated by a magnetic vibrator.

[0017] S52: The material thrown to the periphery of the centrifugal paving disk by centrifugal force falls from the edge, and then continues to be 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.

[0018] Preferably, in the raw material pretreatment stage, the coal liquefaction oil residue subjected to airflow grinding is dried and dehydrated by drying in a vacuum oven at 120° C. for 4 hours.

[0019] Preferably, during the raw material pretreatment stage, the SBS particles crushed by a hammer mill are vacuum-sealed and stored at -20°C.

[0020] Preferably, 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.

[0021] Preferably, the warm mix agent is a fatty acid amide warm mix agent, accounting for 5%.

[0022] Preferably, the dynamic development device comprises an oven, a centrifugal spreading disc is provided 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 provided 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;

[0023] 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 includes a rotating shaft with a hollow structure that passes through the middle of the centrifugal paving disc, 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, and an output end of the driving source is provided with a driving wheel that 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 pipe assembly;

[0024] A cavity is provided inside the centrifugal spreading disc, the pipe assembly is connected to the rotating shaft and the cavity, and a hot air supply pipe extending to the outside of the oven for supplying hot air is provided at the bottom of the rotating shaft, and the hot air supply pipe is connected to the lower end of the rotating shaft.

[0025] Preferably, 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;

[0026] A blocking block is provided 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.

[0027] Preferably, a spiral conveying assembly is provided 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 provided 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 to the first through hole.

[0028] Preferably, the spiral blade is a hollow structure, and the inner walls of the upper and lower ends of the spiral blade are 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.

[0029] Preferably, a hollow power disk is provided at the upper end of the rotating shaft, and power nozzles are evenly arranged around the tangential sides of the power disk. A top cover is provided at the upper end of the oven, and the power disk is located inside the top cover. An exhaust port is provided on one side of the top cover.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] 1. This warm-mix modified asphalt preparation method based on coal liquefaction oil residue uses ultrafine activation of coal liquefaction oil residue and SBS freeze-crushing technology to enhance the interfacial activity of raw materials, realize the resource utilization of solid waste, and reduce the modification cost. At the same time, the staged temperature-controlled miscibility combined with the ultrasonic-assisted dispersion process improves the high-temperature rutting resistance and water stability of the composite modified asphalt.

[0032] 2. This method for preparing warm-mix modified asphalt based on coal liquefaction oil residue can evenly spread the material into a thin layer through the rotatable centrifugal spreading disc set in the dynamic development device, which not only reduces caking and agglomeration, but also allows faster heat transfer and more uniform heating, significantly reducing the temperature difference inside the material, avoiding local overheating or underheating, and allowing a larger processing volume in the same time, and significantly improving production efficiency. In addition, centrifugal force promotes the gradient distribution of coal liquefaction oil residue nanoparticles in the asphalt phase, increasing the molecular contact opportunities, making it easier for the modifier to be evenly mixed. Combined with the dynamic oscillation of the electromagnetic vibrator, the three-dimensional network construction of the SBS molecular chain can be completed at a low temperature of 160°C, reducing VOC emissions, while absorbing coal liquefaction oil residue solid waste and promoting the low-carbon transformation of road materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The disclosure of the present invention is illustrated 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 accompanying drawings, the same reference numerals are used to refer to the same components. Among them:

[0034] Figure 1 The process flow chart of the present invention is schematically shown;

[0035] Figure 2 The structural diagram of the dynamic development device of the present invention is schematically shown;

[0036] Figure 3 The schematic diagram of the structure inside the oven of the present invention is shown schematically;

[0037] Figure 4 The schematic diagram shows the structure of the feeding cylinder and the rotating shaft of the present invention in the disassembled state;

[0038] Figure 5 Schematically shows the structure of the centrifugal paving disc of the present invention from the bottom perspective;

[0039] Figure 6 The cross-sectional structure diagram of the connection between the centrifugal paving disc and the rotating shaft of the present invention is schematically shown;

[0040] Figure 7 The structural diagram of the spiral blade of the present invention is schematically shown.

[0041] Numbers in the figure: 1. oven; 2. feed port; 3. discharge port; 4. top cover; 5. exhaust port; 6. online rheometer probe; 7. hot air supply pipe; 8. driving source; 9. conductive slip ring; 10. feed barrel; 11. centrifugal spreading disc; 12. first connecting pipe; 13. fixing frame; 14. rotating shaft; 15. spiral blade; 16. driven wheel; 17. driving wheel; 18. power disc; 19. power nozzle; 20. second connecting pipe; 21. electromagnetic vibrator; 22. first through hole; 23. cavity; 24. block; 25. second through hole. DETAILED DESCRIPTION

[0042] It is easy to understand that according to the technical solution of the present invention, without changing the essential spirit of the present invention, a person skilled in the art can propose a variety of interchangeable structural modes and implementation modes. Therefore, the following specific embodiments and drawings are only exemplary descriptions of the technical solution of the present invention and should not be regarded as the entire invention or as a limitation or restriction of the technical solution of the present invention.

[0043] According to one embodiment of the present invention, Figure 1-Figure 7 Shown.

[0044] like Figure 1 As shown, a method for preparing warm-mix modified asphalt based on coal liquefaction oil residue comprises the following steps:

[0045] Step 1: Raw material pretreatment: Coal liquefaction residue (DCLR) is pre-crushed with a jaw crusher to a particle size of ≤5mm. It is then jet-milled to 200 mesh at a pressure of 0.8MPa for 15 minutes. Ultrafine grinding with a jet mill to 200 mesh significantly increases the specific surface area and enhances the interface with asphalt. It is then dried in a vacuum oven at 120°C for 4 hours. Compared with conventional atmospheric pressure drying, this reduces thermal oxidation side reactions and preserves active components.

[0046] Table 1 below is a comparative example of DCLR crushing particle size experiment:

[0047] Table 1

[0048]

[0049] As shown in Table 1, 200-mesh crushing increases the specific surface area of ​​coal liquefaction oil residue to 3.5m² / g, which is 94% higher than that of 100-mesh crushing, and the interfacial bonding strength reaches 18MPa, which is doubled compared with 100-mesh crushing. The support content is increased to 5%. Although the content of 300-mesh crushing can reach 6.5%, its energy consumption increases sharply to 150kWh / t, and nano-scale dispersion requires a high-cost stabilizer. Considering the solid waste disposal goals and costs, 200-mesh crushing is the preferred choice.

[0050] Table 2 below is a comparative example of the drying process experiment:

[0051] Table 2

[0052]

[0053] As shown in Table 2, vacuum drying at 120°C reduces thermal oxidation losses compared to the 150°C atmospheric pressure process, increases asphaltene retention by 13%, and has a 180-day storage segregation index of only 0.03, meeting industry quality standards. Compared to vacuum drying at 100°C, drying time is shortened by 50% and energy consumption is reduced by 20%. Although the moisture content is slightly higher, it is still within the allowable range of modified asphalt. Therefore, vacuum drying at 120°C is preferred.

[0054] The SBS is placed in a -30°C liquid nitrogen environment for freezing and then crushed into 0.5-1mm particles using a hammer mill. Specifically, the SBS raw material is immersed in -30°C liquid nitrogen and frozen for 10 minutes to achieve deep embrittlement. It is then quickly transferred to a hammer mill for low-temperature crushing. The particles are controlled to 0.5-1mm through a 1mm / 0.5mm grading screen. The environment is maintained below -15°C throughout the process to prevent reheating and agglomeration. After crushing, the particles are vacuum-sealed and stored at -20°C to achieve low-damage crushing of the molecular chain, increase the specific surface area to 0.8-1.2m² / g, and improve the melt dispersion efficiency.

[0055] It should be noted that SBS is a styrene-butadiene-styrene block copolymer, which is a commonly used thermoplastic elastomer material. Its main function is to give asphalt an elastic recovery ability similar to that of rubber, reduce the risk of cracking, improve high-temperature stability and low-temperature brittle cracking resistance, and enhance anti-aging and anti-fatigue properties. In this step, SBS is subjected to liquid nitrogen freeze-crushing treatment and is made into 0.5-1mm particles by deep-cold embrittlement and low-temperature crushing. This not only maintains the molecular chain structure of the material, but also increases the specific surface area, thereby improving the efficiency of subsequent melt mixing and ultimately improving the comprehensive mechanical properties of the asphalt. Specifically, this is carried out by a liquid nitrogen freeze-crushing machine, which belongs to the existing technology and the specific principle will not be described in detail.

[0056] Table 3 below is a comparative example of SBS pretreatment process experiment:

[0057] Table 3

[0058]

[0059] As shown in Table 3, freezing at -30°C causes SBS to fall below the glass transition temperature, the hammer stress is concentrated at the brittle point, the molecular chain breakage rate is reduced from 25% to 5%, the elastic recovery rate is increased by 40%, the specific surface area of ​​0.5-1 mm particles is four times that of 2-5 mm particles, and the subsequent melt dispersion time is shortened from 90 min to 30 min. Therefore, freezing in a liquid nitrogen environment at -30°C and crushing into 0.5-1 mm particles using a hammer mill is the preferred solution.

[0060] Step 2: Premixing the composite modifier in stages: 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 a speed of 300 rpm for 15 minutes. The high-speed mixer is a two-stage temperature-controlled high-speed mixer, which uses existing known equipment. The specific principle will not be described in detail. In the second stage, the temperature is raised to 160°C, and 6% by mass of SBS and 0.15% by mass of stabilizer are added, and the speed is 500 rpm to stir for 30 minutes until completely melted. This step is a two-stage design of low-temperature premixing and high-temperature melting. In the first stage, DCLR, aromatic oil, and rubber powder are mixed at 80°C to avoid cross-linking of rubber powder caused by 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.

[0061] Step 3: Preheat the asphalt. Heat the petroleum asphalt to 170°C in a pulse ultrasonic shear reactor, add 5% fatty acid amide warm mix agent and shear it. Specifically, shear at 1500 rpm for 10 minutes.

[0062] Modifier blending: The pre-mixed composite modifier is slowly added to the pulse ultrasonic shear reactor and sheared at 170°C for 30 minutes, with ultrasonic assistance turned on for the first 15 minutes to obtain a high-viscosity liquid product. In this step, 20kHz ultrasound is introduced during modifier blending to produce a cavitation effect to break up SBS agglomerates. Compared with traditional pure mechanical shearing, it can improve dispersion efficiency. The ultrasonic pulse cycle is 5s on / 3s off;

[0063] Table 4 below is a comparative example of ultrasonic assist effect experiment:

[0064] Table 4

[0065]

[0066] As shown in Table 4, 20kHz pulsed ultrasound achieves an SBS dispersion efficiency of 98% through cavitation effect, which is 36% higher than that without ultrasound. The interfacial binding energy is increased to 52J / m², and the temperature rise ΔT≤3℃ to avoid thermal damage. Although the dispersion efficiency of 40kHz continuous ultrasound reaches 95%, the energy consumption is doubled. Therefore, pulsed ultrasound is preferred.

[0067] Step 5: The high-viscosity liquid product is transferred into a dynamic development device for constant temperature development at 160°C. The specific development principle is: the high-viscosity liquid product is added from the feed port 2 at the upper end of the dynamic development device to the inner periphery of the top of the centrifugal spreading disk 11 inside the development device, and the driving mechanism drives the centrifugal spreading disk 11 to rotate. Under the action of centrifugal force, the high-viscosity liquid is evenly spread into a thin layer, and 160°C hot air is introduced into the inside of the centrifugal spreading disk 11 to heat the high-viscosity liquid. The centrifugal spreading disk 11 is oscillated by the electromagnetic vibrator 21, and the material thrown to the periphery of the centrifugal spreading disk 11 by the centrifugal force falls from the edge. Then, it is continuously transported to the inner periphery of the top of the centrifugal spreading disk 11 through the spiral conveying assembly at the lower end of the centrifugal spreading disk 11, and continues to be centrifugally spread and heated. During this period, the complex shear modulus is monitored in real time by the online rheometer probe 6, and the development is terminated when the target value is reached.

[0068] During the development stage, a rotating centrifugal spreading disc 11 is superimposed on the dynamic oscillation of an electromagnetic vibrator 21 to induce the reconstruction of the three-dimensional network of the SBS molecular chain through periodic stress. At the same time, an integrated online rheometer monitors the complex shear modulus in real time to achieve intelligent judgment of the development endpoint.

[0069] In this process, the maximum temperature of the entire process is controlled at 170℃, which is 20-30℃ lower than the traditional process. It compensates for the insufficient development caused by low temperature through dynamic oscillation, and can reduce the emission of volatile organic compounds (VOCs) to meet the requirements of green construction.

[0070] Further, such as Figure 2-Figure 7As shown, the dynamic development device specifically includes an oven 1, a centrifugal spreading disc 11 is provided at the inner upper end of the oven 1, and an electromagnetic vibrator 21 is evenly arranged around the bottom of the centrifugal spreading disc 11, the wire of the electromagnetic vibrator 21 can extend upward through the inside of the rotating shaft 14, and a conductive slip ring 9 is provided at the top of the rotating shaft 14, the guide of the electromagnetic vibrator 21 is electrically connected to the conductive slip ring 9, and the conductive slip ring 9 is externally connected to the power supply so as not to affect the rotation, and in order to adapt to high temperatures, a thermal insulation protective cover can be provided on the outside of the wire of the electromagnetic vibrator 21 for protection, which can adapt to the high temperature inside the oven 1. The thermal insulation protective cover adopts conventional technical means and will not be elaborated on. A feed port 2 is provided on one side of the upper end of the oven 1, and one end of the feed port 2 corresponds to the inner periphery of the top of the centrifugal spreading disc 11, a discharge port 3 for discharging is provided at the bottom of the oven 1, and an online rheometer probe 6 is provided through the side wall of the oven 1, and the inner end of the online rheometer probe 6 is used to communicate with the oven The centrifugal paving disc 11 is in contact with the material inside the box 1, and a driving mechanism for driving the centrifugal paving disc 11 to rotate is provided at the upper end of the centrifugal paving disc 11, the driving mechanism includes a rotating shaft 14 which is provided through the middle of the centrifugal paving disc 11 and has a hollow structure, the upper end of the rotating shaft 14 extends to the top of the oven 1, and a driven wheel 16 is provided at the upper end of the rotating shaft 14. A driving source 8 is provided on one side of the upper end of the oven 1, and the driving source 8 is preferably a reduction motor. The output end of the driving source 8 is provided with a driving wheel 17 which is driven to rotate by the driving source 8 and meshes with the driven wheel 16. The centrifugal paving disc 11 and the side wall of the rotating shaft 14 are connected by a pipe assembly, and the pipe assembly includes a first connecting pipe 12 which is provided on the outer periphery of the top of the centrifugal paving disc 11 and a second connecting pipe 20 which is provided on the inner periphery of the top of the centrifugal paving disc 11, and the ends of the first connecting pipe 12 and the second connecting pipe 20 away from the centrifugal paving disc 11 are both connected to 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;

[0071] In order to heat the material by supplying hot air, a cavity 23 is provided on the inner side of the centrifugal spreading disc 11, and the pipe assembly is connected with the rotating shaft 14 and the cavity 23. The bottom of the rotating shaft 14 is provided with a hot air supply pipe 7 extending to the outside of the oven 1 for supplying hot air, and the hot air supply pipe 7 is connected with the lower end of the rotating shaft 14. In order to allow the hot air to enter the second connecting pipe 20, the cavity 23, and the first connecting pipe 12 in sequence, a block 24 is provided on the inner side of the rotating shaft 14 between the upper ends of the first connecting pipe 12 and the second connecting pipe 20.

[0072] In order to realize the circulating paving and heating of the material, a spiral conveying assembly is provided at the lower end of the centrifugal paving disc 11, and the spiral conveying assembly includes a spiral blade 15 arranged 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, and a feeding barrel 10 located outside the spiral blade 15 is provided at the lower end of the oven 1, and the upper end of the feeding barrel 10 extends to the inner side of the first through hole 22 and is movably connected to the first through hole 22. Specifically, a fixing frame 13 is provided on the side wall of the feeding barrel 10, and the other end of the fixing frame 13 is fixed to the inner wall of the oven 1.

[0073] In order to ensure uniform heating during the conveying stage of the spiral blade 15, the spiral blade 15 is set to a hollow structure, and the inner walls of the upper and lower ends of the spiral blade 15 are provided with second through holes 25 connected to the interior of the spiral blade 15, and the spiral blade 15 is connected to the rotating shaft 14 through the second through holes 25.

[0074] In addition, in order to reduce the energy consumption of the driving source 8, a hollow power disk 18 is provided at the upper end of the rotating shaft 14, and power nozzles 19 are evenly arranged around the tangential side of the power disk 18. A top cover 4 is provided at the upper end of the oven 1, and the power disk 18 is located on the inner side of the top cover 4. An exhaust port 5 is provided on one side of the top cover 4, and the driving source 8 is installed at the upper end of the top cover 4.

[0075] The specific working principle of the dynamic development device is as follows:

[0076] During use, the high-viscosity liquid product obtained by shearing in the pulse ultrasonic shearing reactor is introduced into the top inner periphery of the centrifugal spreading disc 11 through the feed port 2. During this period, the driving source 8 drives the active wheel 17 to rotate, and the active wheel 17 drives the rotating shaft 14 to rotate through the driven wheel 16. The rotating shaft 14 drives the centrifugal spreading disc 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 disc 11, the material entering from the feed port 2 can be evenly and circumferentially landed on the top of the centrifugal spreading disc 11. Under the rotation of the centrifugal spreading disc 11, the material The material generates centrifugal force, which can spread the material evenly into a thin layer. The hot air supply pipe 7 is connected to an external heat source to supply hot air of about 160°C to the inside of the rotating shaft 14. The hot air enters the inside of the rotating shaft 14 through the hot air supply pipe 7. Part of the hot air will enter the inside of the spiral blade 15 through the second through hole 25 at the lower end of the spiral blade 15. The remaining hot air directly rises along the inside of the rotating shaft 14. The hot air 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 and merge with the other part of the hot air, and then enter the second connecting pipe 20 under the blockage 24. The hot air enters the centrifugal spreading disc 11 through the second connecting pipe 20, and the centrifugal spreading disc 11 conducts heat, and the hot air heats the centrifugal spreading disc 11, thereby the centrifugal spreading disc 11 heats the material, and then the hot air enters the upper end of the rotating shaft 14 through the first connecting pipe 12, and is finally discharged from the upper end of the rotating shaft 14. The material on the top of the centrifugal spreading disc 11 will gradually be thrown off from the edge, and then rotated upward by the spiral blade 15. The material contacts the surface of the spiral blade 15 and is evenly heated and dried by the spiral blade 15 again, and then returns to the top of the centrifugal spreading disc 11, and the cycle continues. The electromagnetic vibrator 21 oscillates the centrifugal paving disc 11, during which the complex shear modulus is monitored in real time by the online rheometer probe 6. When the target value is reached, the development is terminated, and the rotating shaft 14 is reversed for discharge. The rotating centrifugal paving disc 11 cooperates with the dynamic oscillation of the electromagnetic vibrator 21, and in conjunction with online rheological monitoring, the modified asphalt can form a stable three-dimensional network structure at a low temperature of 160°C. Compared with traditional processes, the processing temperature is reduced by 20-30°C, saving energy consumption, while ensuring that the complex shear modulus reaches above 2.0kPa, significantly improving high-temperature rutting resistance and low-temperature cracking resistance.

[0077] It should be noted that the hot air discharged from the upper end of the rotating shaft 14 will be discharged tangentially from the power nozzle 19. The reaction torque of the power nozzle 19 is consistent with the driving direction of the driving source 8, which directly reduces the output torque requirement of the motor and indirectly reduces power consumption and current, making the motor run more efficiently and easily, which is conducive to energy saving.

[0078] The technical scope of the present invention is not limited to the contents of the above description. 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 finely grinding it to 200 mesh by air flow milling, and then drying and dehydrating it; the drying and dehydration treatment is specifically drying it in a vacuum oven at 120°C for 4 hours; 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 were 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 mix agent for shearing; S4: Slowly add the premixed composite modifier into the pulse ultrasonic shear reactor, maintain the shear temperature 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 growth device for growth at a constant temperature of 160°C. The specific growth steps include: S51: A high-viscosity liquid product is added 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. Under the action of centrifugal force, the high-viscosity liquid is evenly spread into a thin layer. 160°C hot air is introduced into 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 centrifugal force falls from the edge, and then continues to be 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: During the raw material pretreatment stage, the SBS particles crushed by a hammer mill were vacuum-sealed and stored at -20°C.

3. 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.

4. 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%.

5. The method for preparing warm-mix modified asphalt based on coal liquefaction oil residue according to any one of claims 1 to 4, characterized in that: The dynamic development device includes an oven, a centrifugal spreading disc is provided 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 provided 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 includes a rotating shaft with a hollow structure that passes through the middle of the centrifugal paving disc, 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, and an output end of the driving source is provided with a driving wheel that 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 pipe assembly; A cavity is provided inside the centrifugal spreading disc, the pipe assembly is connected to the rotating shaft and the cavity, and a hot air supply pipe extending to the outside of the oven for supplying hot air is provided at the bottom of the rotating shaft, and the hot air supply pipe is connected to the lower end of the rotating shaft.

6. The method for preparing warm-mix modified asphalt based on coal liquefaction oil residue according to claim 5, 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 provided 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.

7. The method for preparing warm-mix modified asphalt based on coal liquefaction oil residue according to claim 5, characterized in that: A spiral conveying assembly is provided at the lower end of the centrifugal spreading disc, and the spiral conveying assembly includes a spiral blade provided on the outer wall of the lower end of the rotating shaft. A first through hole corresponding to the upper end of the spiral blade is provided in the middle of the centrifugal spreading disc. 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 inside of the first through hole and is movably connected to the first through hole.

8. The method for preparing warm-mix modified asphalt based on coal liquefaction oil residue according to claim 7, characterized in that: The spiral blade is a hollow structure, and the inner walls of 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.

9. The method for preparing warm-mix modified asphalt based on coal liquefaction oil residue according to claim 6, characterized in that: A hollow power disc is provided 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 provided at the upper end of the oven, and the power disc is located inside the top cover. An exhaust port is provided on one side of the top cover.

Images