Preparation equipment and preparation method of graphene concentrated solution for modified asphalt

Abstract

The invention discloses preparation equipment and preparation method of a graphene concentrated solution for modified asphalt, the preparation equipment comprises a first mixing and stirring mechanism, an ultrasonic oscillation mechanism, a grinding mechanism and a second mixing and stirring mechanism, the first mixing and stirring mechanism is connected with the ultrasonic oscillation mechanism, the ultrasonic oscillation mechanism is connected with the grinding mechanism, and the second mixing and stirring mechanism is connected with the grinding mechanism. And the grinding mechanism is connected with the second mixing and stirring mechanism. Through cooperative dispersion of mixing and stirring and multi-stage ultrasonic oscillation, the dispersity of graphene is improved step by step, graphene microchip aggregates are effectively stripped, a uniform and stable graphene concentrated solution is formed, all the mechanisms are connected in series, integration is high, continuous production can be achieved, material transfer links are reduced, pollution risks are reduced, efficiency is improved, and the method is suitable for industrial production. The prepared graphene concentrated solution is uniform in dispersion and free of agglomeration, the crack resistance, the high temperature resistance and the durability of the graphene concentrated solution can be remarkably improved when the graphene concentrated solution is used for modifying asphalt, and the requirements of high-grade road engineering are met.

Description

Technical Field

[0001] The present invention relates to the technical field of graphene concentrate preparation, and particularly relates to an apparatus and method for preparing a graphene concentrate for modified asphalt. Background Art

[0002] In recent years, due to its excellent mechanical, thermal and electrical properties, graphene has shown broad application prospects in the field of modified asphalt. However, the uniform dispersion of graphene in asphalt remains a technical difficulty. In the prior art, simple mechanical stirring and other methods are usually used to prepare graphene concentrate, and the following problems exist in this method:

[0003] 1. Poor dispersion effect: Traditional mechanical stirring is difficult to effectively peel off the agglomerated structure of graphene microflakes, resulting in uneven distribution of graphene in the concentrate and affecting the performance of modified asphalt;

[0004] 2. Low process efficiency: In order to improve the dispersion effect, traditional mechanical stirring requires repeated operations many times, which is time-consuming and energy-consuming;

[0005] 3. Insufficient stability: The concentrate is prone to secondary agglomeration during subsequent mixing with asphalt, reducing the uniformity and durability of the final product.

[0006] Therefore, there is an urgent need to develop an efficient and stable apparatus and process to solve the problem of graphene dispersion in asphalt and improve the comprehensive performance of modified asphalt. Summary of the Invention

[0007] The purpose of the present invention is to provide an apparatus and method for preparing a graphene concentrate for modified asphalt. Through the synergistic dispersion of multi-stage ultrasonic oscillation of a mixing and stirring machine, the dispersion degree of graphene is gradually increased, the agglomerates of graphene microflakes are effectively peeled off, and a uniform and stable graphene concentrate is formed.

[0008] In order to achieve the above object of the invention, the technical scheme adopted by the present invention is as follows:

[0009] According to one aspect of the present invention, an apparatus for preparing a graphene concentrate for modified asphalt is provided, including a first mixing and stirring mechanism, an ultrasonic oscillation mechanism, a grinding mechanism and a second mixing and stirring mechanism;

[0010] The first mixing and stirring mechanism is connected to the ultrasonic oscillation mechanism, the ultrasonic oscillation mechanism is connected to the grinding mechanism, and the grinding mechanism is connected to the second mixing and stirring mechanism;

[0011] The first mixing and stirring mechanism is used for mixing and stirring a coupling agent and graphene microflakes to obtain a primary dispersion liquid;

[0012] The ultrasonic oscillation mechanism is used to oscillate and disperse the primary dispersion liquid to obtain the secondary dispersion liquid;

[0013] The grinding mechanism is used to grind the secondary dispersion liquid to obtain the tertiary dispersion liquid;

[0014] The second mixing and stirring mechanism is used to mix and stir the rubber oil and the tertiary dispersion liquid to obtain the graphene concentrate.

[0015] Preferably, the first mixing and stirring mechanism includes a first stirring box body, a first stirring motor, a rotating main pipe and stirring branch pipes;

[0016] The first stirring motor is fixedly arranged at the upper end of the first stirring box body. The rotating main pipe is arranged in the first stirring box body. The upper end of the rotating main pipe is fixedly connected with the first stirring motor. The lower end of the rotating main pipe is rotatably connected with the bottom of the first stirring box body. A plurality of stirring branch pipes are provided. The plurality of stirring branch pipes are arranged at intervals and staggeredly along the axial direction of the stirring main pipe. Each stirring branch pipe is connected with the rotating main pipe.

[0017] Preferably, it further includes a pneumatic component. The pneumatic component includes an air compressor, a gas guide pipe and an electric valve. One end of the gas guide pipe is connected with the air compressor, and the other end is connected with the rotating main pipe through a sealing bearing. The outer ring of the sealing bearing is fixedly arranged at the bottom of the first stirring box body. The rotating main pipe is fixedly connected with the inner ring of the sealing bearing. The gas guide pipe is fixedly connected with the outer ring of the sealing bearing. The gas guide pipe is communicated with the rotating main pipe.

[0018] Preferably, the ultrasonic oscillation mechanism includes a plurality of sequentially connected ultrasonic oscillation devices. The ultrasonic oscillation device includes an ultrasonic oscillation box body, an ultrasonic generator, a transducer and a horn. The transducer and the horn are both arranged in the ultrasonic oscillation box body. The ultrasonic generator is connected with the transducer, and the transducer is connected with the horn.

[0019] Preferably, the grinding mechanism includes a grinding cavity, a grinding motor, a main shaft and discs. The grinding motor is fixedly arranged at one end of the grinding cavity. The main shaft and the discs are both arranged in the grinding cavity. One end of the main shaft is fixedly connected with the grinding motor. A plurality of discs are provided. The plurality of discs are fixedly arranged at intervals along the axial direction of the main shaft.

[0020] Preferably, the second mixing and stirring mechanism includes a second stirring box body, a second stirring motor, a rotating shaft and a spiral blade. The second stirring motor is fixedly arranged at the upper end of the second stirring box body. The rotating shaft and the spiral blade are arranged in the second stirring box body. The rotating shaft is fixedly connected to the output end of the second stirring motor, and the spiral blade is fixedly arranged on the rotating shaft.

[0021] Preferably, a method for preparing a graphene concentrate for modified asphalt is based on the equipment for preparing a graphene concentrate for modified asphalt according to any one of claims 1-6, and includes the following steps:

[0022] S1. Put the coupling agent and graphene microsheets into the first mixing and stirring mechanism for mixing and stirring to obtain a first-stage dispersion;

[0023] S2. Put the first-stage dispersion into the ultrasonic oscillation mechanism for ultrasonic oscillation, and repeat the oscillation 8-11 times to obtain a second-stage dispersion;

[0024] S3. Put the second-stage dispersion into the grinding mechanism for grinding to obtain a third-stage dispersion;

[0025] S4. Put the third dispersion and rubber oil into the second mixing and stirring mechanism for mixing and stirring to obtain a graphene concentrate for modified asphalt.

[0026] Preferably, in step S1, the coupling agent is a titanate coupling agent or a silane coupling agent.

[0027] Preferably, in step S1, the input amounts of the coupling agent and the graphene microsheets are: 77-94 parts of the coupling agent and 6-23 parts of the graphene microsheets.

[0028] Preferably, in step S4, the viscosity of the rubber oil is: 40 ≤ viscosity ≤ 100.

[0029] In summary, due to the adoption of the above technical solutions, the beneficial effects of the present invention are as follows:

[0030] Through the synergistic dispersion of the multi-stage ultrasonic oscillation of the mixing blender, the present invention gradually improves the dispersion degree of graphene, effectively peels off the graphene microsheet aggregates, forms a uniform and stable graphene concentrate, and each mechanism is connected in series, with high integration, can realize continuous production, reduce the material transfer link, reduce the pollution risk, improve the efficiency, ensure the high stability of the prepared concentrate and the compatibility with asphalt. The obtained graphene concentrate is evenly dispersed and has no agglomeration. When used for modified asphalt, it can significantly improve its crack resistance, high temperature resistance and durability, meeting the requirements of high-grade road engineering. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1It is a schematic diagram of the overall structure of the present invention;

[0032] Figure 2 It is a schematic diagram of the structure of the first mixing and stirring mechanism of the present invention;

[0033] Figure 3 It is a schematic diagram of the structure of the ultrasonic oscillation mechanism of the present invention;

[0034] Figure 4 It is a schematic diagram of the structure of the grinding mechanism of the present invention;

[0035] Figure 5 It is a schematic diagram of the structure of the second mixing and stirring mechanism of the present invention.

[0036] In the drawings, 1 is the first mixing and stirring mechanism; 2 is the ultrasonic oscillation mechanism; 3 is the grinding mechanism; 4 is the second mixing and stirring mechanism; 100 is the first stirring box body; 101 is the first stirring motor; 102 is the rotating main pipe; 103 is the stirring branch pipe; 104 is the air vent hole; 105 is the air guide pipe; 200 is the ultrasonic oscillation box body; 201 is the transducer; 202 is the amplitude transformer; 300 is the grinding cavity; 301 is the grinding motor; 302 is the main shaft; 303 is the disc; 400 is the second stirring box body; 401 is the second stirring motor; 402 is the rotating shaft; 403 is the spiral blade. Detailed implementation manners

[0037] To make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the following preferred embodiments are cited with reference to the accompanying drawings to further elaborate on the present invention. However, it should be noted that many details listed in the specification are only for enabling the reader to have a thorough understanding of one or more aspects of the invention, and these aspects of the present invention can be implemented even without these specific details.

[0038] Please refer to Figures 1 to 5 , the present invention provides a graphene concentrate production device and production method for modified asphalt, and the technical solutions are as follows:

[0039] A production device for graphene concentrate for modified asphalt, comprising a first mixing and stirring mechanism 1, an ultrasonic oscillation mechanism 2, a grinding mechanism 3 and a second mixing and stirring mechanism 4. The first mixing and stirring mechanism 1 includes a first stirring box body 100, a first stirring motor 101, a rotating main pipe 102 and stirring branch pipes 103. The first stirring motor 101 is fixedly arranged at the upper end of the first stirring box body 100, and the rotating main pipe 102 is arranged inside the first stirring box body 100. The upper end of the rotating main pipe 102 is fixedly connected to the first stirring motor 101, the lower end of the rotating main pipe 102 is rotatably connected to the bottom of the first stirring box body 100, a plurality of stirring branch pipes 103 are provided, and the plurality of stirring branch pipes 103 are arranged at intervals and displaced along the axial direction of the stirring main pipe. Each stirring branch pipe 103 is connected to the rotating main pipe 102. The rotating pipe is driven to rotate by the first stirring motor 101, the rotating pipe drives the stirring branch pipes 103 to rotate, and the stirring branch pipes 103 stir the coupling agent and graphene microflake mixture put into the first stirring box body 100, accelerating the mixing reaction of the coupling agent and graphene microflakes and promoting the dispersion of graphene microflakes.

[0040] Further, in order to further improve the stirring effect, in this embodiment, a pneumatic component is further included. The pneumatic component includes an air compressor, a guide air pipe 105 and an electric valve. One end of the guide air pipe 105 is connected to the air compressor, and the other end is rotatably connected to the rotating main pipe 102 through a sealing bearing. The outer ring of the sealing bearing is fixedly arranged at the bottom of the first stirring box body 100. The lower end of the rotating main pipe 102 is fixedly connected to the inner ring of the sealing bearing, and the inner ring communicates with the rotating main pipe 102. One end of the guide air pipe 105 away from the air compressor is fixedly connected to the outer ring of the sealing bearing, and the guide air pipe 105 communicates with the rotating main pipe 102. A plurality of air holes 104 are opened along the axial direction of the stirring branch pipe 103 on the stirring branch pipe 103, and the stirring branch pipe 103 communicates with the rotating main pipe 102. The air compressor compresses air, and then the compressed air is released through the guide air pipe 105. The compressed air passes through the rotating main pipe 102 and the stirring branch pipes 103 and is ejected from the air holes 104. The ejected gas cooperates with the rotating stirring branch pipes 103 to enhance the stirring effect, improve the stirring efficiency and enhance the dispersion of graphene.

[0041] The ultrasonic oscillation mechanism 2 includes a plurality of sequentially connected ultrasonic oscillation devices. In this embodiment, there are 5 ultrasonic oscillation devices, and the 5 ultrasonic oscillation devices are sequentially connected. The ultrasonic oscillation device includes an ultrasonic oscillation box body 200, an ultrasonic generator, a transducer 201, and a horn 202. The ultrasonic oscillation box body 200 of the first ultrasonic oscillation device is connected to the first stirring box body 100 through a pipeline. The ultrasonic oscillation box body 200 is used to receive the primary stirring mixture from the first stirring box body 100. The ultrasonic oscillation box body 200 of the second ultrasonic oscillation device is connected to the ultrasonic oscillation box body 200 of the first ultrasonic oscillation device through a pipeline, and a valve is provided on the pipeline. And so on until the 5 ultrasonic oscillation devices are sequentially connected. Both the transducer 201 and the horn 202 are arranged in the ultrasonic oscillation box body 200. The ultrasonic generator is connected to the transducer 201, and the transducer 201 is connected to the horn 202. The ultrasonic generator is used to convert the commercial power into a high-frequency electrical signal. The transducer 201 is prepared by using piezoelectric ceramics (such as PZT) or magnetostrictive materials and is used to convert electrical energy into mechanical vibration. The horn 202 is used to amplify the amplitude of the transducer 201. The combined number of the transducer 201 and the horn 202 in each ultrasonic oscillation box body 200 can be set according to actual needs, and 1 - 30 pieces can be set. Through the high-frequency vibration of ultrasonic waves, periodic compression and expansion are generated in the liquid to form tiny bubbles. When the bubbles collapse instantaneously, local high temperature, high pressure, and high-speed micro-jet are generated. The cavitation shock wave directly impacts the graphene sheet layer, stripping the stacked structure. The high-pressure jet penetrates between the graphene layers, overcoming the van der Waals force. Moreover, the ultrasonic waves generate high-frequency vibration in the liquid to form turbulence, applying shear stress to the graphene, which can tear the multi-layer graphene into single-layer or few-layer structures and prevent the secondary aggregation of the exfoliated graphene. At the same time, part of the ultrasonic energy is converted into heat energy. Appropriate heating can reduce the viscosity of the liquid, improve the permeability of the solvent molecules, accelerate the exfoliation process, and promote the adsorption of surfactants.

[0042] The grinding mechanism 3 is a sand mill, which includes a grinding chamber 300, a grinding motor 301, a main shaft 302 and a disc 303. The grinding chamber 300 is connected to the ultrasonic oscillation box body 200 of the last ultrasonic oscillation device in the ultrasonic oscillation mechanism 2 through a pipeline, and is used to receive the secondary oscillation mixture from the ultrasonic oscillation box body 200. The grinding motor 301 is fixedly arranged at one end of the grinding chamber 300. Both the main shaft 302 and the disc 303 are arranged in the grinding chamber 300. One end of the main shaft 302 is fixedly connected to the grinding motor 301. A plurality of discs 303 are arranged, and the plurality of discs 303 are fixedly arranged at intervals along the axial direction of the main shaft 302. By adding grinding media into the grinding chamber 300, and then using the grinding motor 301 to drive the main shaft 302 to rotate, and the main shaft 302 drives the disc 303 to rotate, the secondary oscillation mixture can be effectively ground in the grinding chamber 300, and the agglomeration of graphene microflakes can be broken by high-speed shear force, so that it is evenly dispersed in the matrix, promoting the coating of the coupling agent on the surface of graphene, enhancing the interfacial bonding, realizing the nano-level uniform distribution of the coupling agent and graphene, and avoiding local concentration differences.

[0043] The product of the grinding machine is a tertiary grinding mixture. To improve the dispersibility, the tertiary grinding mixture can be put back into the first mixing and stirring mechanism 1, the ultrasonic oscillation mechanism 2 and the grinding mechanism 3 repeatedly for many times, so as to ensure the complete dispersion of graphene microflakes. It should be noted that the first mixing and stirring mechanism 1, the ultrasonic oscillation mechanism 2 and the grinding mechanism 3 are all connected by pipelines, and pumps are arranged on the pipelines for the material transfer between the mechanisms and the repeated action between the mechanisms.

[0044] The second mixing and stirring mechanism 4 includes a second stirring box body 400, a second stirring motor 401, a rotating shaft 402 and a spiral blade 403. The second stirring box body 400 is connected to the grinding chamber 300, and is used to receive the tertiary grinding mixture and simultaneously receive the added rubber oil. The second stirring motor 401 is fixedly arranged at the upper end of the second stirring box body 400. The rotating shaft 402 and the spiral blade 403 are arranged in the second stirring box body 400. The rotating shaft 402 is fixedly connected to the output end of the second stirring motor 401, and the spiral blade 403 is fixedly arranged on the rotating shaft 402. After adding rubber oil to the tertiary grinding mixture, the two are mixed and stirred by the second mixing and stirring mechanism 4 to ensure that the graphene microflakes are evenly dispersed in the viscous rubber oil, avoid agglomeration, shorten the mixing time, improve the interfacial bonding effect and stability between the coupling agent and graphene, and prevent leakage and volatilization at the same time. After being stirred by the second mixing and stirring mechanism 4, the graphene concentrate for modified asphalt can be obtained.

[0045] The present invention also discloses a method for preparing a graphene concentrate for modified asphalt, and the preparation method includes the following steps:

[0046] S1. Put the coupling agent and graphene microflakes into the first mixing and stirring mechanism 1 for mixing and stirring to obtain the first-stage dispersion liquid.

[0047] Specifically, the coupling agent is a silane coupling agent. Put 50 Kg of silane coupling agent and 15 Kg of graphene microflakes into the first mixing and stirring box body, and use the first mixing and stirring mechanism 1 to stir the mixed coupling agent and graphene microflakes to make them fully react to obtain the first-stage dispersion liquid. The silanol groups generated by the hydrolysis of the silane coupling agent combine with the oxygen-containing functional groups on the surface of graphene to form chemical bonds or physical adsorption, reducing the agglomeration of graphene. Improve the uniform dispersion of graphene in matrices such as polymers and coatings, and enhance the homogeneity of the composite material. The organic functional groups of the silane react with the matrix to form a bridge, improving the interfacial strength between graphene and the matrix.

[0048] S2. Put the first-stage dispersion liquid into the ultrasonic oscillation mechanism 2 for ultrasonic oscillation, and repeat the oscillation 8 - 11 times to obtain the second-stage dispersion liquid.

[0049] S3. Put the second-stage dispersion liquid into the grinding mechanism 3 for grinding to obtain the third-stage dispersion liquid.

[0050] S4. Put the third dispersion liquid and rubber oil into the second mixing and stirring mechanism 4 for mixing and stirring to obtain the graphene concentrate for modified asphalt.

[0051] Specifically, put the third dispersion liquid and rubber oil into the second mixing and stirring mechanism 4 for mixing and stirring. Select the viscosity of the rubber oil to be greater than or equal to 40 and less than or equal to 100. By mixing the rubber oil and the third dispersion liquid, ensure the uniform dispersion of graphene microflakes in the viscous rubber oil, avoid agglomeration, shorten the mixing time, improve the interfacial bonding effect and stability between the coupling agent and graphene, and at the same time prevent leakage and volatilization.

[0052] The above is only the preferred embodiment of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A graphene concentrate production device for modified asphalt, characterized in that: It includes a first mixing and stirring mechanism, an ultrasonic oscillation mechanism, a grinding mechanism and a second mixing and stirring mechanism; The first mixing and stirring mechanism is connected to the ultrasonic oscillation mechanism, the ultrasonic oscillation mechanism is connected to the grinding mechanism, and the grinding mechanism is connected to the second mixing and stirring mechanism; The first mixing and stirring mechanism is used to mix and stir the coupling agent and the graphene microsheets to obtain a primary dispersion; The ultrasonic oscillation mechanism is used to oscillate and disperse the first-stage dispersion to obtain a second-stage dispersion; The grinding mechanism is used to grind the secondary dispersion to obtain a tertiary dispersion; The second mixing and stirring mechanism is used to mix and stir the rubber oil and the tertiary dispersion to obtain a graphene concentrate.

2. The equipment for producing graphene concentrated liquid for modified asphalt according to claim 1, characterized in that: The first mixing and stirring mechanism comprises a first stirring box, a first stirring motor, a rotating main pipe and a stirring branch pipe; The first stirring motor is fixedly arranged at the upper end of the first stirring box body, the rotating main pipe is arranged in the first stirring box body, the upper end of the rotating main pipe is fixedly connected to the first stirring motor, and the lower end of the rotating main pipe is rotatably connected to the bottom of the first stirring box body. A plurality of stirring branch pipes are arranged, and the plurality of stirring branch pipes are staggered and spaced along the axial direction of the stirring main pipe, and each stirring branch pipe is connected to the rotating main pipe.

3. The equipment for producing graphene concentrated liquid for modified asphalt according to claim 2, characterized in that: It also includes a pneumatic component, which includes an air compressor, an air duct and an electric valve. One end of the air duct is connected to the air compressor, and the other end is connected to the rotating main pipe through a sealing bearing. The outer ring of the sealing bearing is fixedly arranged at the bottom of the first stirring box body, the rotating main pipe is fixedly connected to the inner ring of the sealing bearing, the air duct is fixedly connected to the outer ring of the sealing bearing, and the air duct is communicated with the rotating main pipe.

4. The equipment for producing graphene concentrated liquid for modified asphalt according to claim 2, characterized in that: The ultrasonic oscillation mechanism includes a plurality of ultrasonic oscillation devices connected in sequence, and the ultrasonic oscillation device includes an ultrasonic oscillation box, an ultrasonic generator, a transducer and an amplitude transformer. The transducer and the amplitude transformer are both arranged in the ultrasonic oscillation box, the ultrasonic generator is connected to the transducer, and the transducer is connected to the amplitude transformer.

5. The equipment for producing graphene concentrated liquid for modified asphalt according to claim 1, characterized in that: The grinding mechanism includes a grinding chamber, a grinding motor, a spindle and a disc. The grinding motor is fixedly arranged at one end of the grinding chamber. The spindle and the disc are both arranged in the grinding chamber. One end of the spindle is fixedly connected to the grinding motor. A plurality of discs are arranged, and the plurality of discs are fixedly arranged at intervals along the axial direction of the spindle.

6. The equipment for producing graphene concentrated liquid for modified asphalt according to claim 1, characterized in that: The second mixing and stirring mechanism includes a second stirring box, a second stirring motor, a rotating shaft and a spiral blade. The second stirring motor is fixedly arranged at the upper end of the second stirring box. The rotating shaft and the spiral blade are arranged in the second stirring box. The rotating shaft is fixedly connected to the output end of the second stirring motor, and the spiral blade is fixedly arranged on the rotating shaft.

7. A method for producing a graphene concentrate for modified asphalt, based on the graphene concentrate for modified asphalt production equipment according to any one of claims 1 to 6, characterized in that: The following steps are involved: S1, putting the coupling agent and the graphene microsheets into a first mixing and stirring mechanism for mixing and stirring to obtain a first-stage dispersion; S2, putting the first-stage dispersion into an ultrasonic oscillation mechanism for ultrasonic oscillation, and repeating the oscillation 8-11 times to obtain a second-stage dispersion; S3, putting the second-stage dispersion into a grinding mechanism for grinding to obtain a third-stage dispersion; S4. Put the third dispersion liquid and rubber oil into a second mixing and stirring mechanism for mixing and stirring to obtain a graphene concentrated liquid for modified asphalt.

8. The method for preparing a graphene concentrated solution for modified asphalt according to claim 7, characterized in that: In step S1, the coupling agent is a titanate coupling agent or a silane coupling agent.

9. The method for preparing a graphene concentrated solution for modified asphalt according to claim 7, characterized in that: In step S1, the input amounts of the coupling agent and the graphene microsheets are: 77 to 94 parts of the coupling agent and 6 to 23 parts of the graphene microsheets.

10. The method for preparing a graphene concentrated solution for modified asphalt according to claim 7, characterized in that: In step S4, the viscosity of the rubber oil is: 40≤viscosity≤100.

Images