DBD powder processing device and method based on three-dimensional turbulent mixing technology

Abstract

This invention discloses a DBD powder processing device and method based on three-dimensional turbulent mixing technology, belonging to the field of powder uniform processing technology. The device includes a gas supply unit, a DBD reactor, and a monitoring unit. The gas supply unit is connected to the DBD reactor and is used to provide working gas and reaction medium to the DBD reactor. The DBD reactor includes a device platform, a plasma cylinder, and a second electric motor. A stirring paddle and a first electric motor are installed inside the plasma cylinder. The first electric motor drives the stirring paddle to rotate and stir the powder to be processed inside the plasma cylinder. The plasma cylinder is fixed on the inclined surface of the device platform. The second electric motor is located at the bottom of the device platform and is fixedly connected to the plasma cylinder, driving the plasma cylinder to rotate. The monitoring unit is connected to the DBD reactor and is used to discharge and monitor the powder to be processed inside the plasma cylinder. This invention achieves uniform powder dispersion while using low-temperature plasma modification technology, suppressing powder adhesion and agglomeration.

Description

Technical Field

[0001] This application belongs to the field of powder uniform processing technology, specifically, it relates to a DBD powder processing device and method based on three-dimensional turbulent mixing technology. Background Technology

[0002] Nanoparticles, with their unique physical and chemical properties, show broad application prospects in multiple fields. By uniformly dispersing them in matrix materials, the overall performance of materials can be effectively improved, driving innovation and development in engineering, environmental protection, energy, and other fields. For example, adding magnesium oxide nanoparticles to polyethylene cable insulation can synergistically enhance its electrical, thermal, and mechanical properties.

[0003] However, for magnesium oxide, especially at the nanoscale, driven by extremely high surface energy, van der Waals forces, and polar interactions, magnesium oxide agglomerates in order to reach a stable state with the lowest energy. Simultaneously, due to the fundamental difference in polarity and chemical properties, interfacial incompatibility exists. Agglomerates make it difficult to achieve uniform nanoscale dispersion of magnesium oxide in the matrix, while the incompatible interface introduces numerous pores and defects. These interfacial defects, along with the agglomerates, become weaknesses contributing to charge concentration and crack initiation, resulting in the overall performance of the composite medium falling short of expectations.

[0004] Solving the problems of agglomeration and interfacial compatibility is key to preparing high-performance polyethylene / magnesium oxide nanocomposite insulating materials. Currently, the main approach is through nanoparticle surface modification, which can be broadly categorized into physical and chemical methods. Physical modification uses external forces such as mechanical force, electric fields, magnetic fields, or heat to directly break down or weaken the agglomeration structure between powder particles and promote their physical contact, wetting, and embedding with the coating material, thereby reducing interfacial incompatibility while achieving dispersion. Chemical modification focuses on utilizing surfactants and other substances to react chemically with the powder, achieving surface functionalization. This effectively reduces the surface energy of the powder, fundamentally inhibiting its agglomeration tendency, while significantly enhancing its interfacial compatibility with organic matrix materials.

[0005] However, these traditional methods all face significant challenges: physical methods are simple to operate and applicable to powder particles of various shapes and materials, but the interfacial bonding between the coating layer and the matrix is ​​weak, making delamination prone to occur. Chemical methods, while improving dispersion stability, require a long time and raise issues related to waste disposal, safe production, and environmental protection. Furthermore, existing methods generally suffer from poor process controllability and insufficient repeatability, hindering the full realization of the properties of nanocomposites. Therefore, developing novel mixing technologies that can achieve efficient and uniform dispersion of nanoparticles without compromising their intrinsic properties has become an important research direction in this field.

[0006] In recent years, low-temperature plasma technology has provided a new solution to the aforementioned challenges. This technology effectively activates the surface of materials and generates a large number of free radicals in a short time by treating the material surface with low-temperature plasma. With the help of an ionizing medium, target polymer groups can be precisely implanted into the powder surface, thereby strengthening the interfacial bonding between the filler and the matrix and significantly improving the tightness and stability of their connection. Using low-temperature plasma to treat powder fillers not only enhances the interfacial interaction between particles and the matrix but also avoids the cumbersome drying steps and waste liquid pollution problems common in traditional wet chemical modification, offering green and environmentally friendly advantages. However, relying solely on this technology for surface modification of powders still makes it difficult to ensure that the plasma-treated particles achieve uniform dispersion and mixing on a macroscopic scale within the matrix. For example, the prior art discloses a DBD (Dielectric Barrier Discharge) reactor that achieves dynamic powder processing through rotating electrodes. It can significantly improve the uniformity and stability of plasma, use plasma technology to improve the interfacial incompatibility problem that occurs during powder coating, and at the same time enhance processing efficiency and extend equipment life. However, this device is difficult to solve the problems of powder agglomeration and wall adhesion, which can easily cause uneven powder processing. In addition, this device cannot solve the problem of airtightness, which can easily lead to powder leakage and waste of resources.

[0007] Therefore, in order to achieve uniform dispersion and suppress powder adhesion and agglomeration while using low-temperature plasma modification technology, it is necessary to design a plasma powder modification device that can effectively modify powders. Summary of the Invention

[0008] To address the shortcomings of existing technologies, this invention provides a DBD powder processing device and method based on three-dimensional turbulent mixing technology.

[0009] The present invention adopts the following technical solution.

[0010] The first aspect of the present invention discloses a DBD powder processing device based on three-dimensional turbulent mixing technology, including a gas supply unit, a DBD reactor and a monitoring unit, wherein the gas supply unit is connected to the DBD reactor and is used to provide working gas and reaction medium to the DBD reactor; The DBD reactor includes: a device platform, a plasma cylinder, and a second electric motor. The plasma cylinder is equipped with a stirring paddle and a first electric motor. The first electric motor drives the stirring paddle to rotate and stir the powder to be processed in the plasma cylinder. The plasma cylinder is fixed on the inclined platform of the device platform. The second electric motor is located at the bottom of the device platform and is fixedly connected to the plasma cylinder, driving the plasma cylinder to rotate. The monitoring unit is connected to the DBD reactor and is used to discharge and monitor the powder to be treated inside the plasma cylinder.

[0011] Preferably, the plasma tube comprises: an upper annular cover, a container, a tungsten rod, and a lower annular cover; The tungsten rod is placed in a container, and the upper and lower circular covers are connected to the two ends of the container, respectively. The container is filled with the powder to be processed, and the stirring paddle is installed on the upper circular cover.

[0012] Preferably, the first motor is mounted on the upper ring cover, the stirring shaft is connected to the first motor, the stirring paddle is mounted on the stirring shaft, and the first motor drives the stirring shaft to rotate, thereby driving the stirring paddle to rotate. The upper ring cover is provided with a second air inlet and an air outlet. The stirring shaft is located on the second air inlet. The stirring shaft is provided with a first air inlet. The upper ring cover is provided with a groove inside.

[0013] Preferably, the DBD reactor further includes: an upper conductive slip ring and a lower conductive slip ring; The tungsten rods are arranged in an interlaced manner inside the container to form an interdigitated structure. The two ends of the tungsten rods pass through the reserved holes in the upper and lower circular covers, and are defined as the high-voltage end and the low-voltage end, respectively. The high-voltage end is connected to the upper conductive slip ring through a wire, and the low-voltage end is connected to the lower conductive slip ring. The upper and lower conductive slip rings are then connected to the monitoring unit.

[0014] Preferably, the platform of the device is inclined. When the sealed container is tilted and rotated, the powder is simultaneously subjected to the combined effects of centrifugal force and gravity, thus obtaining the core mechanical criterion for inhibiting powder adhesion to the wall during tilted rotation:

[0015] In the formula: The angle of inclination between the central axis of the container and the vertical direction. R is the rotational angular velocity of the container, and R is the inner diameter of the container. The coefficient of friction between the powder particles and the inner wall of the container is given by , and g is the acceleration due to gravity; the angle of inclination is given by . The range is 20°-30°.

[0016] Preferably, the container includes: mounting holes, a reaction device outer shell, and a reaction device inner wall. The reaction device outer shell is provided with staggered mounting holes near the reaction device inner wall for fixing tungsten rods.

[0017] Preferably, the DBD powder processing device adopts coordinated control of in-tank stirring drive and overall tank drive, wherein the in-tank motor is a first motor, used to drive the stirring paddle to generate shearing and disturbance inside the container tank; the out-of-tank motor is a second motor, used to drive the container tank to generate rotational disturbance, and the first motor and the second motor have different rotational speeds.

[0018] A second aspect of the present invention discloses a DBD powder processing method, based on a DBD powder processing apparatus based on three-dimensional turbulent mixing technology as described in the first aspect, comprising the following steps: An experimental platform was set up, a DBD reactor was installed, and the nanopowder to be treated was placed in the DBD reactor. Start the gas supply unit to continuously feed the working gas carrying the reaction medium into the DBD reactor, turn on the motor and adjust it to make the powder rotate and tumble evenly in the DBD reactor. Once a stable inert atmosphere is formed inside the DBD reactor, the monitoring unit is activated to match and adjust the power parameters until a stable discharge plasma is generated inside the plasma chamber. The power parameters are maintained to process the dynamic nanopowder at regular intervals. After the processing is completed, the motor and monitoring unit are turned off to terminate the plasma discharge. Then all gas supply is stopped, and the DBD powder processing device is allowed to cool naturally to complete the entire process.

[0019] Preferably, the step of starting and adjusting the motor involves first starting the first motor and observing whether the stirring paddle can stir the powder normally. If it cannot stir normally, the parameters of the first motor are adjusted. If it can stir normally, the second motor is then started and adjusted.

[0020] Preferably, the timed processing of the nanopowder to be processed in a dynamic state is as follows: When the first and second motors start together, the mixed cycle begins. At time t=0, the second motor rotates forward while the first motor rotates in reverse, and... Synchronous commutation is performed at all times, so that the two motors are in sync. Then the second motor reverses while the first motor runs forward until... Finish.

[0021] Compared with the prior art, the beneficial effects of the present invention include at least the following: This invention proposes a DBD powder processing device based on three-dimensional turbulent mixing technology, which improves the wall adhesion and agglomeration phenomena that exist in the traditional coaxial DBD part when processing powder, making the powder processing more uniform.

[0022] To address the issue of powder sticking to the walls, this device tilts the DBD reaction vessel. The tilt angle allows gravity to partially counteract centrifugal force, reducing powder adhesion. Simultaneously, the device utilizes three-dimensional turbulence characteristics—two motors that rotate the vessel itself and the internal stirring brush in opposite directions at varying speeds—to both agitate and lift the powder, further reducing agglomeration. Combining the tilt angle and three-dimensional turbulence properties achieves a more uniform powder processing effect.

[0023] In addition, this device adopts a sealed treatment method to solve the problem of powder leakage and reduce resource waste. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of this disclosure or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of the overall structure of the DBD powder processing device based on three-dimensional turbulent mixing technology in this invention; Figure 2 This is a schematic diagram of the DBD reactor using the three-dimensional turbulent mixing technology of this invention; Figure 3 This is a schematic diagram of the upper seat circular cover device in this invention; Figure 4 This is a schematic diagram of the combination device of the upper ring cover and the stirring paddle in this invention; Figure 5 This is a schematic diagram of the lower seat circular cover device in this invention; Figure 6 This is a partial schematic diagram of the plasma container device in this invention; Figure 7 This is a schematic diagram of the electrode portion of the device in this invention; Figure 8 This is a schematic diagram of the slip ring portion of the device in this invention; Figure 9 This is a schematic diagram of the placement platform device in this invention; Figure 10 This is a schematic diagram of the tungsten rod in this invention; Figure 11 This is a schematic diagram of the DBD process for treating nanopowders in this invention.

[0026] In the picture: 1. High-pressure gas cylinder; 2. One-way valve; 3. Bubbling device; 4. Flow meter; 5. Mixing chamber; 6. Compressor; 7. Device platform; 8. Upper ring cover; 801. Upper ring cover hole; 802. First motor; 803. Air outlet; 804. First air inlet; 805. Second air inlet; 806. Stirring shaft; 9. Agitator; 10. Container / tank; 1001. Mounting hole; 1002. Outer shell of the reaction apparatus; 1003. Inner wall of the reaction apparatus; 11. Tungsten rod; 12. Lower base ring cover; 1201. Lower base ring outer frustum; 1202. Lower base ring groove; 1203. Lower base ring cover boss; 1204. Lower base ring cover hole; 1205. Motor socket; 13. Second electric motor; 14. Upper conductive slip ring; 1401. Rotating component; 1402. Fixed component; 1403. Inner hole; 1404. Inlet hole; 1405. Outlet hole; 15. Lower conductive slip ring, 16. Excitation power supply, 17. Current coil, 18. High voltage probe, 19. Oscilloscope. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of this invention. The embodiments described in this application are merely some embodiments of this invention, and not all embodiments. Based on the spirit of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this invention.

[0028] Atmospheric pressure cryogenic plasma, a non-equilibrium plasma formed through gas discharge under normal pressure, is characterized by an electron temperature much higher than that of heavy particles. This allows it to exhibit high chemical reactivity while maintaining an overall system temperature close to room temperature. The plasma is rich in highly reactive components such as high-energy electrons, excited-state particles, and free radicals. These components are high-energy and highly reactive, effectively driving many chemical reactions that are difficult to occur under conventional conditions at room temperature and pressure. Based on this unique advantage, atmospheric pressure cryogenic plasma technology has been widely applied in several cutting-edge fields, including material surface modification, thin film preparation, chemical synthesis, ozone generation, and nanomaterial processing.

[0029] Low-temperature plasma technology, as a highly promising method for material surface modification, has important applications in the field of powder coating. This method utilizes high-energy electrons, active ions, and excited-state particles generated in plasma to undergo a series of complex physical and chemical reactions with reactants, thereby achieving a uniform and dense coating layer on the powder surface. This technology boasts advantages such as high processing efficiency, low reaction temperature, strong surface activation ability, good selectivity, and fast conversion rate. Specifically, through an ionizing medium, target polymer groups can be introduced into the powder surface, forming a robust core-shell structure through chemical bonds. This coating method not only enhances the durability of powder performance but also improves its interfacial compatibility and functional stability in composite materials.

[0030] Among various plasma generation methods, dielectric barrier discharge (DBD) has become one of the most commonly used plasma generation technologies in practical applications due to its simple device structure, stable discharge process, and ease of implementation and control. This invention designs a DBD powder processing device based on turbulent three-dimensional mixing technology. This device utilizes DBD plasma to activate the reaction medium, introducing specific functional groups onto the powder surface to enhance its chemical compatibility with the matrix, resulting in a tighter bond between the two. Furthermore, the device employs an inclined reaction vessel design to suppress powder adhesion to the walls; and utilizes three-dimensional turbulent technology to effectively disperse powder agglomerates. Through the synergistic effect of the above methods, the macroscopic properties of the composite material are ultimately optimized and improved.

[0031] like Figure 1-10 As shown, Embodiment 1 of the present invention provides a DBD powder processing device based on turbulent three-dimensional mixing technology, including an air supply unit, a DBD reactor and a monitoring unit connected in sequence; The gas supply unit includes: a high-pressure gas cylinder 1, a one-way valve 2, a bubbling device 3, a flow meter 4, and a mixing chamber 5; the high-pressure gas cylinder 1 and the bubbling device 3 are used to store the working gas and the reaction medium, respectively.

[0032] In a preferred but non-limiting embodiment of the present invention, the working gas is an inert gas Ar, and the reaction medium is KH550. After the device is started, the high-pressure gas cylinder 1 releases gas, pushing the reaction medium along the pipeline into the mixing chamber 5.

[0033] During this process, a one-way valve 2 is installed between the high-pressure gas cylinder 1 and the flow meter 4 to effectively prevent reverse airflow and ensure one-way gas passage within the gas pipe. The flow meter 4 is responsible for real-time monitoring of airflow data to ensure controllable operation.

[0034] For media in different states, the DBD powder processing device employs corresponding mixing methods: if the medium is gaseous, it is pre-mixed with Ar gas in the mixing chamber 5 before being introduced into the discharge region; if the medium is liquid, Ar gas is used as the carrier gas to carry it into the discharge region. The ratio of the reaction medium to the working gas can be precisely adjusted using the flow meter 4.

[0035] like Figure 2 As shown, the DBD reactor includes: a compressor 6, a device platform 7, a plasma cylinder, a second motor 13, an upper conductive slip ring 14, and a lower conductive slip ring 15; The plasma cylinder includes: an upper ring cover 8, a stirring paddle 9, a container 10, a tungsten rod 11, and a lower ring cover 12. The tungsten rod 11 is inserted into the container 10, and the lower ring cover 12 is then tightly connected to the container 10 to prevent powder leakage when the powder is placed. The powder to be processed is then added to the container 10, and the stirring paddle 9 is installed on the upper ring cover 8 according to the amount of powder. The upper ring cover 8 is then closed.

[0036] A clamping device 6 is provided on the upper end of the device platform 7. The clamping device 6 passes through the upper conductive slip ring 14 and is connected to the plasma cylinder. The second motor 13 is provided at the bottom of the device platform 7 and is fixedly connected to the plasma cylinder. The lower conductive slip ring 15 is provided above the second motor 13.

[0037] Specifically, the plasma cylinder containing powder and installed is placed on the second motor 13 and tightly connected. The clamping device 6 is adjusted to fix the plasma cylinder on the device platform 7. The above process is carried out by tightly connecting the devices together to avoid failure when the second motor 13 rotates. Then, the excitation power supply and ground wire are connected to the upper conductive slip ring 14 and the lower conductive slip ring 15 respectively. The upper conductive slip ring 14 and the lower conductive slip ring 15 are then connected to the monitoring unit respectively. After the gas pipe is connected, the equipment is started.

[0038] like Figure 9 As shown, the clamp 6 is designed to firmly fix the plasma cylinder to the device platform 7 when the container 10 is placed on the platform, preventing instability caused by the rotation of the second motor 13. The platform 7 is tilted to create an angle after the container 10 is placed on it. During rotation, the component of gravity counteracts part of the centrifugal force, thereby reducing adhesion to the walls and ensuring more thorough mixing of the powder and plasma. Furthermore, the second motor 13 has adjustable rotation speed and direction, which works in conjunction with the motor on the stirrer 9 to achieve opposite and variable-speed rotation, further reducing agglomeration. Two conductive slip rings prevent the wires from tangling during reactor rotation.

[0039] Specifically, the device platform 7 described in this invention is inclined. When the sealed container 10 is tilted and rotated, the powder particles are simultaneously subjected to the combined action of centrifugal force and gravity. Compared with the vertical rotation state, the component of gravity along the axial direction of the cylinder wall will drive the particles to form a continuously tumbling flow layer, which greatly shortens the static adhesion time of the particles on the wall surface and fundamentally alleviates the problems of powder compaction and adhesion to the wall.

[0040] The force condition under which the particles overcome static friction to flow during this process is:

[0041] In the formula: The angle of inclination between the central axis of container 10 and the vertical direction. R is the rotational angular velocity of container 10, and R is the inner diameter of container 10. denoted as the coefficient of friction between the powder particles and the inner wall of container 10, m as the mass of a single powder particle, and g as the acceleration due to gravity. The component of gravity sliding down the cylinder wall can overcome the frictional constraint of the wall, allowing the powder to maintain dynamic flow rather than static adhesion to the wall.

[0042] By simplifying the above force condition formulas, we can obtain the core mechanical criterion for inhibiting powder adhesion to the wall during tilting and rotation, which is used to set the tilt angle between the central axis of container 10 and the vertical direction:

[0043] This formula clarifies the quantitative relationship between process parameters and the anti-sticking effect, namely, by adjusting the tilt angle of the container tank 10. With rotational angular velocity This invention strengthens the sliding driving effect of gravity on powder particles, weakens the wall-adhesion and pressing effect caused by centrifugal force, ensures that the powder on the wall surface continuously updates its contact state, and eliminates static wall adhesion. This application effectively solves the technical problem of powder wall adhesion through this mechanism design.

[0044] In a preferred but non-limiting embodiment of the invention, the angle of the tilt angle is... The tilt angle is 20°-30°, more preferably, the tilt angle is... It is 25°.

[0045] This application adopts a coordinated control of in-tank stirring drive and overall tank drive based on the inclined device platform 7. The in-tank motor, namely the first motor 802, is used to drive the stirring paddle 9 to generate shearing and disturbance inside the container tank 10; the out-of-tank motor, namely the second motor 13, is used to drive the container tank 10 to generate rotational disturbance. By coupling and adjusting the rotation speed, rotation direction and timing phase of the two motors, the powder particles undergo direction switching and speed disturbance in the processing zone, thereby improving the contact uniformity between the powder and the DBD discharge active area and reducing the risk of local agglomeration.

[0046] Specifically, the controller will perform each mixing cycle The rotation is divided into a forward rotation segment and a reverse rotation segment, with the forward rotation segment lasting for the same duration as the reverse rotation segment. The duration of the forward rotation segment is... The duration of the reversal segment is ,satisfy Two electric motors are started to process the powder.

[0047] At the reversal point, the drive parameters of the two motors are switched; the stirring speed is set to [value] in the forward and reverse rotation segments respectively. and ,in and They are not equal. The mixing cycle... The amount of material can be adjusted according to the characteristics of the powder to maintain powder circulation and suppress agglomeration.

[0048] Specifically, during the DBD powder processing, the rotation direction of the second motor 13 of the device platform is the forward rotation direction; the second motor 13 of the device platform and the second motor 802 corresponding to the stirring paddle 9 perform differential reverse rotation control.

[0049] During the forward rotation phase, the second motor 13 rotates forward at 300 rpm, while the first motor 802 rotates in reverse at 360 rpm, thereby obtaining the speed ratio. , here Rotation speed ratio used for alumina or magnesium oxide speed ratio For reference only. If other powders are used, then... Corresponding changes:

[0050] At the switching moment of the reverse segment, the controller synchronously switches the rotation direction of the two motors, so that the second motor 13 of the device platform reverses and the speed is still 300 rpm, while the first motor 802 rotates forward and the speed is still 360 rpm, and continues until the end of the reverse segment.

[0051] Furthermore, let the total duration of the timing processing be a mixed cycle. At t=0, it begins to operate in the forward rotation phase as described above, with the second motor 13 rotating forward and the first motor 802 rotating in reverse. Synchronous commutation is performed at all times, so that the two motors are in sync. Then, the reverse segment of "second motor 13 reverses / first motor 802 forwards" is executed until... Finish.

[0052] The aforementioned setting of synchronous reversing of the two motors at a preset time point is used to disperse and redistribute the powder position in the time dimension of potential low disturbance / stagnation areas, thereby reducing the probability of the continued existence of "dead zones" and improving the overall processing uniformity, and enhancing the three-dimensional turbulence processing effect of powder in the DBD processing chamber.

[0053] like Figure 3 As shown, the upper ring cover 8 has a hole 801 on its side with a diameter of 10 mm. The main purpose of this design is to lead out the wire of the tungsten rod 11 so as to connect it to the upper conductive slip ring 14. The first motor 802 is installed on the upper ring cover 8, and its purpose is to rotate the stirring paddle 9.

[0054] The upper circular cover 8 has an outlet and an inlet for gas flow, and a gap to protect the wire connection of the tungsten rod 11 to prevent damage to the tungsten rod 11 when the reactor rotates. The upper circular cover 8 also has a hole to connect with the upper conductive slip ring 14. The lower circular cover 12 does not have an outlet or inlet and has a reserved space for the tungsten rod 11 to protect it. It also has a hole to connect with the lower conductive slip ring 15.

[0055] Specifically, the upper annular cover 8 is provided with a second air inlet 805 and an air outlet 803, with corresponding diameters of 14 mm and 12 mm, respectively. A stirring shaft 806 is mounted on the second air inlet 805 and is tightly connected to a first motor 802, causing the first motor 802 to drive the stirring shaft 806 to rotate. A first air inlet 804, with a diameter of 14 mm, is distributed on the stirring shaft 806 to allow gas to fill the interior of the device, ensuring thorough mixing of the gas and powder. The upper annular cover 8 has a groove 807 inside, with an outer diameter of 240 mm, an inner diameter of 200 mm, and a groove depth of 30 mm. This design provides space for the exposed tungsten rod 11 to connect to external electrical wires.

[0056] Among them, such as Figure 10 As shown, tungsten rods 11 are arranged in an interlaced manner inside the container 10, forming an interdigitated structure. The two ends of the tungsten rods 11 pass through pre-drilled holes in the upper annular cover 8 and the lower annular cover 12, and are defined as the high-voltage end and the low-voltage end, respectively. The high-voltage end is connected to the upper conductive slip ring 14 via a wire, and then the excitation power supply 16 is connected from the upper conductive slip ring 14. The low-voltage end is first connected to the lower conductive slip ring 15, and then grounded, thus completing the construction of the entire electrical circuit.

[0057] like Figure 4The diagram shows a schematic of the device after the upper ring cover 8 and the stirring paddle 9 are combined according to the present invention. The stirring shaft 806 has a length of 300 mm, an outer diameter of 16 mm, and an inner radius that is the diameter of the second air inlet 805, which is 14 mm. The stirring paddle 9 has a hole with the same diameter as the outer diameter of the stirring shaft 806 so that it can be tightly engaged with the stirring shaft 806.

[0058] The number and shape of the agitator 9 can be freely selected according to the requirements and quantity of the powder being processed, ensuring more thorough powder mixing. Specifically, the agitator 9 can be installed at different positions along the axial direction of the agitator shaft 806, and the agitator 9 is coaxially connected to the agitator shaft 806, so that the agitator 9 rotates synchronously with the agitator shaft 806 in terms of structure; therefore, under different axial height conditions, the rotational speed of the agitator 9 remains synchronized with the agitator shaft 806. The variation in the installation position and number of agitator 9 depends on the axial height reached by the amount of powder placed in the cavity; the powder height should be higher than the agitator 9, thereby optimizing the distribution of powder in the DBD processing cavity and reducing wall adhesion and agglomeration.

[0059] As shown in Figure 5, the lower seat ring cover 12 includes: a lower seat ring outer truncated cone 1201, a lower seat ring groove 1202, a lower seat ring cover boss 1203, a lower seat ring cover hole 1204, and a motor socket 1205. The lower seat annular groove 1202 is disposed between the lower seat annular outer truncated cone 1201 and the lower seat annular cover protrusion 1203, the lower seat annular cover hole 1204 is disposed on the side of the lower seat annular outer truncated cone 1201, and the motor socket 1205 is disposed in the middle of the lower seat annular cover protrusion 1203.

[0060] The lower annular cover protrusion 1203 is designed for insertion into the container 10, with a corresponding diameter of 200 mm, which corresponds to the inner diameter of the container 14's inner wall. The lower annular groove 1202 has an inner diameter of 200 mm, an outer diameter of 240 mm, and a groove depth of 30 mm. This design provides sufficient space for the exposed tungsten rod 11 to facilitate grounding. The lower annular outer frustum 1201, which connects to the side wall of the container 10, can withstand significant rotational forces; its inner diameters are 240 mm and 260 mm, respectively. The lower annular cover hole 1204 is primarily designed to facilitate the routing of the tungsten rod 11's wires, allowing it to connect to the lower conductive slip ring 15.

[0061] The diameter of the motor socket 1205 is 10 mm and the depth is 20 mm, which is the same as the rotating shaft of the second motor 13. The purpose is to allow the two to fit together better, thereby making the rotation more stable.

[0062] like Figure 6As shown, the container 10 is made of quartz glass, which can effectively suppress the transition from surface discharge to arc discharge and maintain a stable plasma state. The container 10 consists of three parts: mounting holes 1001, a reaction device shell 1002, and a reaction device inner wall 1003, wherein the diameter of the reaction device inner wall 1003 is 200 mm. The reaction device shell 1002 has staggered mounting holes 1001 near the reaction device inner wall 1003 for fixing tungsten rods 11 as electrodes. These holes are 280 mm long, while the entire reactor is 290 mm long, leaving a 10 mm axial margin. This design avoids plasma erosion of the upper and lower circular cover 8 and lower circular cover 12 due to the holes penetrating the entire inner wall, and also provides operating space for external wiring at the end of the tungsten rod 11. Ultimately, this allows plasma to be generated uniformly over a relatively long area of ​​approximately 280 mm, thereby improving the overall energy utilization efficiency.

[0063] It is worth noting that tungsten was chosen as the core material for the electrode. In practical applications, this electrode needs to meet several performance requirements: strong electron emission capability, high temperature resistance and non-melting, high mechanical strength, low loss rate, long service life, and ease of handling. Tungsten rods, with their high melting point of 3410 ℃, boiling point of approximately 5900 ℃, high strength of 850~1100 MPa, low thermal conductivity, and low volatility at high temperatures, comprehensively meet these requirements. When high voltage is applied, the tungsten electrode can rapidly heat to extremely high temperatures, achieving efficient electron emission and carrying extremely high current densities, making it particularly suitable as an electrode material. Figure 7 As shown, the tungsten rod 11 used in this paper has a diameter of 10 mm and a total length of 290 mm.

[0064] like Figure 8 As shown, the upper conductive slip ring 14 is composed of a rotating component 1401, a fixed component 1402, an inner hole 1403, an inlet hole 1404, and an outlet hole 1405. The fixed component 1402 is sleeved inside the rotating component 1401, and the inner hole 1403 is formed by hollowing out the middle of the fixed component 1402. The inlet hole 1404 is provided on the rotating component 1401, and the outlet hole 1405 is provided on the fixed component 1402.

[0065] The fixed component 1402 has an outer diameter of 60 mm and an inner diameter of 80 mm. The diameter of the inner hole 1403 is the same as the inner diameter of the fixed component 1402. This is to ensure a tight fit with the clamping device 6 and maintain stability when the rotating component 1401 rotates. The rotating component 1401 has an inner diameter of 80 mm and an outer diameter of 100 mm. This design is advantageous because it has the same diameter as the ring of the fixed component 1402, making it less prone to damage. The rotating component 1401 and the fixed component 1402 each have an inlet hole 1404 and an outlet hole 1405, respectively. The inlet hole 1404 is connected to the excitation power supply 16, and the outlet hole 1405 is connected to the tungsten rod 11 inside the container 10. During device operation, because the conductive slip ring and the reactor are coaxial, it is ensured that the rotating component 1401 will not cause the wires to become entangled when rotating, thereby achieving the purpose of continuous power supply during rotation.

[0066] The monitoring unit includes: an excitation power supply 16, a current coil 17, a high-voltage probe 18, and an oscilloscope 19; The excitation power supply 16 can be a nanosecond pulse power supply, and its key parameters such as discharge voltage, pulse frequency, rise time, fall time, and pulse width can all be independently adjusted. The oscilloscope 19 is used to record voltage and current waveforms in real time, providing data support for subsequent analysis of discharge characteristics. The high-voltage probe 18 provides electrical isolation when measuring high-voltage signals, ensuring the feasibility and safety of direct high-voltage measurement. The current coil 17 has a dual function, including suppressing current fluctuations and enabling circuit tuning and frequency selection.

[0067] like Figure 11 As shown, Embodiment 2 of the present invention provides a DBD powder processing method, based on the DBD powder processing apparatus described in Embodiment 1, including the following steps: Step 1: Build the experimental platform, install the DBD reactor, place the nanopowder to be processed in the DBD reactor, and start the DBD powder processing device. In a preferred but non-limiting embodiment of the present invention, step 1 specifically includes: Step 1.1: Connect the second motor 13 to the device platform 7 to provide power for the rotation of the DBD reactor; then, insert 12 tungsten rods 11 as discharge electrodes into the corresponding holes on the wall of the container tank 10 to form an interdigitated electrode structure, and pass the exposed leads at both ends through the reserved holes 801 of the upper ring cover 8 and the reserved holes 1204 of the lower ring cover 12 respectively, and complete the connection of the high voltage and grounding circuit through the conductive slip ring; Step 1.2: Seal the lower seat ring cover 12 to the lower end of the container 10, then add a certain amount of nano powder to be processed, and then determine the number of stirring paddles 9 to be installed according to the process requirements to make the plasma and powder mix more evenly. Finally, cover the upper seat ring cover 8.

[0068] More preferably, to ensure the airtightness of the reaction space, flexible airtight tape needs to be carefully wrapped around all joints of the upper ring cover 8, the container 10 and the lower ring cover 12.

[0069] Step 1.3: After assembly, place the DBD reactor on the output shaft of the second motor 13 on the device platform 7, and adjust the upper clamp 6 to press the upper ring cover 8, thereby achieving stability and sealing of the DBD reactor during dynamic operation.

[0070] Step 2: Open the high-pressure gas cylinder and continuously introduce the working gas containing the reaction medium into the DBD reactor. Turn on the motor and adjust it to make the powder rotate and tumble evenly in the DBD reactor.

[0071] In a preferred but non-limiting embodiment of the present invention, step 2 specifically includes: Step 2.1: Enter the gas supply and plasma treatment stage. The working gas is high-purity Ar gas, and its flow rate is monitored in real time by the flow meter 4. First, Ar gas is pre-introduced for a period of time to fully replace the air in the reactor and ensure the initial environment is pure. Then, another high-pressure gas cylinder is turned on to continuously introduce Ar gas carrying the reaction medium into the system. During this process, the pressure device 6 is quickly locked again to cope with pressure changes and ensure that the seal is absolutely reliable. Step 2.2: First, turn on the first motor 802 of the stirring paddle 9 and observe whether the stirring paddle 9 can stir the powder normally. If it cannot stir normally, adjust the parameters of the first motor 802. If it can stir normally, then start the second motor 13 of the device platform 7 and set an appropriate speed parameter. Observe the rotation effect to make the powder rotate and tumble more violently and further reduce the agglomeration phenomenon.

[0072] The stirring effect is judged by whether the powder can be lifted and tumbled; the rotation effect is judged by the lifting and tumbling effect of the powder, and reduces the phenomenon of sticking to the wall.

[0073] Step 3: After a stable inert atmosphere is formed in the DBD reactor, the excitation power supply 16 is turned on to match the power supply parameters. The electrical parameters are gradually adjusted until a large-volume, high-intensity and uniformly distributed stable discharge plasma is generated in the container 10. This optimal parameter is maintained to perform timed processing on the nanopowder in dynamic state.

[0074] The timed processing of the dynamically moving nanopowder is performed when the first motor 802 and the second motor 13 start together, entering the mixing cycle. At t=0, it begins to run in the forward rotation phase according to the sequence of "second motor 13 forward rotation / first motor 802 reverse rotation", and then... Synchronous commutation is performed at all times, so that the two motors are in sync. Then, the reverse segment of "second motor 13 reverses / first motor 802 forwards" is executed until... Finish.

[0075] Step 4: After the processing is completed, turn off the motor and excitation power supply 16 to terminate the plasma discharge. Then stop all gas supply and wait for the DBD powder processing device to cool down naturally to complete the entire process.

[0076] In a preferred but non-limiting embodiment of the present invention, the DBD powder processing device employs both a parameter-adjustable nanosecond pulse power supply and an AC power supply. The voltage adjustment range of the nanosecond pulse power supply is 500 V - 30 kV, preferably 5 kV - 10 kV; the frequency adjustment range is 500 Hz - 20 kHz, preferably 2 kHz - 6 kHz. The adjustable AC power supply controls the motor speed, with a speed range of 100 rpm - 300 rpm, preferably 200 rpm. The plasma discharge gas introduced into the device can be argon, helium, or nitrogen, etc., with argon being preferred. The pre-gas flow rate can be adjusted from 10 mL / min to 1 L / min, preferably 500 mL / min - 800 mL / min, and the pre-gas flow time can be from 1 min to 6 min, preferably 3 min. This device can process various inorganic and organic material powders, including but not limited to magnesium oxide nanoparticles and boron nitride nanosheets, with the particle powder processing diameter ranging from 10 nm to 200 μm.

[0077] This invention proposes a DBD powder processing device based on three-dimensional turbulent mixing technology. Utilizing low-temperature atmospheric plasma to treat nanoparticles, it represents a highly efficient surface modification method. By activating the material surface through low-temperature plasma, it promotes the breaking and recombination of existing chemical bonds, thereby constructing new surface chemical structures and morphologies, ultimately achieving precise control over material properties. This invention tilts the DBD reaction device, using the tilt angle to offset some of the centrifugal force with the component of gravity, thus reducing powder adhesion to the walls and resulting in more uniform powder processing. Addressing the powder agglomeration problem in traditional coaxial DBD processing, this invention leverages the three-dimensional turbulent characteristics of the device. Through the separate action of two motors, the container and the stirring brush inside the container rotate in opposite directions at varying speeds, simultaneously lifting and stirring the powder, reducing agglomeration. Furthermore, the tilt angle of the device platform is freely adjustable, and different shapes and numbers of stirring paddles can be installed according to the quality and quantity of the powder to control the degree of agglomeration and adhesion to the walls during processing.

[0078] Compared to the physical processing methods mentioned above, this device does not require a high-temperature, high-pressure environment and can operate at room temperature and pressure. Furthermore, the equipment is simple to assemble, easier to clean, and parts are easier to replace. Compared to traditional chemical techniques, plasma technology is used to process nanomaterials. Energy injection brings the surface to a high-energy state, triggering the breaking and recombination of chemical bonds, thereby generating new surface structures and functional groups. This method effectively optimizes the interfacial properties between materials, enhances mixing, and, as a dry process, offers advantages such as high efficiency and no chemical pollution. Compared to atomic layer deposition (ALD) solutions, this device is more efficient and faster in processing powders. It also has lower environmental and equipment requirements, eliminating the need for complex vacuum equipment, making it a low-cost powder processing device. Moreover, compared to traditional coaxial DBD, this invention, on the one hand, reduces wall adhesion by tilting the reaction device, using gravity to offset some centrifugal force; on the other hand, it employs three-dimensional turbulence technology, using two motors to cause the container itself and the internal stirring brush to rotate in opposite directions at varying speeds. This effectively reduces powder agglomeration. The combined effect of these two factors promotes the improvement of powder dispersion and processing uniformity.

[0079] This disclosure can be a system, method, and / or computer program product. A computer program product may include a computer-readable storage medium having computer-readable program instructions loaded thereon for causing a processor to implement various aspects of this disclosure.

[0080] Computer-readable storage media can be tangible devices capable of holding and storing instructions for use by an instruction execution device. Computer-readable storage media can be, for example—but not limited to—electrical storage devices, magnetic storage devices, optical storage devices, electromagnetic storage devices, semiconductor storage devices, or any suitable combination of the foregoing. More specific examples (a non-exhaustive list) of computer-readable storage media include: portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), static random access memory (SRAM), portable compact disc read-only memory (CD-ROM), digital multifunction disc (DVD), memory sticks, floppy disks, mechanical encoding devices, such as punch cards or recessed protrusions storing instructions thereon, and any suitable combination of the foregoing. The computer-readable storage media used herein are not to be construed as transient signals themselves, such as radio waves or other freely propagating electromagnetic waves, electromagnetic waves propagating through waveguides or other transmission media (e.g., light pulses through fiber optic cables), or electrical signals transmitted through wires.

[0081] The computer-readable program instructions described herein can be downloaded from computer-readable storage media to various computing / processing devices, or downloaded via a network, such as the Internet, local area network, wide area network, and / or wireless network, to an external computer or external storage device. The network may include copper transmission cables, fiber optic transmission, wireless transmission, routers, firewalls, switches, gateway computers, and / or edge servers. A network adapter card or network interface in each computing / processing device receives the computer-readable program instructions from the network and forwards them to the computer-readable storage media in the respective computing / processing device.

[0082] Computer program instructions used to perform the operations of this disclosure may be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine-dependent instructions, microcode, firmware instructions, status setting data, or source code or object code written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Smalltalk, C++, etc., and conventional procedural programming languages ​​such as the "C" language or similar programming languages. The computer-readable program instructions may execute entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving a remote computer, the remote computer may be connected to the user's computer via any type of network—including a local area network (LAN) or a wide area network (WAN)—or may be connected to an external computer (e.g., via the Internet using an Internet service provider). In some embodiments, electronic circuitry, such as programmable logic circuitry, field-programmable gate arrays (FPGAs), or programmable logic arrays (PLAs), is personalized by utilizing the status information of the computer-readable program instructions to implement various aspects of this disclosure.

[0083] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the protection scope of the claims of the present invention.

Claims

1. A DBD powder processing device based on three-dimensional turbulent mixing technology, comprising an air supply unit, a DBD reactor, and a monitoring unit, characterized in that: The gas supply unit is connected to the DBD reactor and is used to provide the DBD reactor with working gas and reaction medium; The DBD reactor includes: a device platform (7), a plasma cylinder and a second motor (13). The plasma cylinder is equipped with a stirring paddle (9) and a first motor (802). The first motor (802) drives the stirring paddle (9) to rotate and stir the powder to be processed in the plasma cylinder. The plasma cylinder is fixed on the inclined platform of the device platform (7). The second motor (13) is located at the bottom of the device platform (7) and is fixedly connected to the plasma cylinder, driving the plasma cylinder to rotate. The monitoring unit is connected to the DBD reactor and is used to discharge and monitor the powder to be treated inside the plasma cylinder.

2. The DBD powder processing device based on three-dimensional turbulent mixing technology according to claim 1, characterized in that: The plasma tube includes: an upper circular cover (8), a container (10), a tungsten rod (11), and a lower circular cover (12). The tungsten rod (11) is placed in the container (10), the upper ring cover (8) and the lower ring cover (12) are respectively connected to the two ends of the container (10), the container (10) is filled with powder to be processed, and the stirring paddle (9) is installed on the upper ring cover (8).

3. The DBD powder processing device based on three-dimensional turbulent mixing technology according to claim 2, characterized in that: The first motor (802) is mounted on the upper ring cover (8), the stirring shaft (806) is connected to the first motor (802), and the stirring paddle (9) is mounted on the stirring shaft (806). The first motor (802) drives the stirring shaft (806) to rotate, thereby driving the stirring paddle (9) to rotate. The upper ring cover (8) is provided with a second air inlet (805) and an air outlet (803). The stirring shaft (806) is located on the second air inlet (805). The stirring shaft (806) is provided with a first air inlet (804). The upper ring cover (8) is provided with a groove (807).

4. The DBD powder processing device based on three-dimensional turbulent mixing technology according to claim 3, characterized in that: The DBD reactor further includes an upper conductive slip ring (14) and a lower conductive slip ring (15). The tungsten rods (11) are arranged in an interlaced manner inside the container (10) to form an interdigitated structure. The two ends of the tungsten rods (11) pass through the reserved holes of the upper ring cover (8) and the lower ring cover (12), and are defined as the high-voltage end and the low-voltage end, respectively. The high-voltage end is connected to the upper conductive slip ring (14) through a wire, and the low-voltage end is connected to the lower conductive slip ring (15). The upper conductive slip ring (14) and the lower conductive slip ring (15) are then connected to the monitoring unit.

5. The DBD powder processing device based on three-dimensional turbulent mixing technology according to claim 2, characterized in that: The platform (7) of the device is inclined. When the sealed container (10) is tilted and rotated, the powder is simultaneously subjected to the combined action of centrifugal force and gravity, thus obtaining the core mechanical criterion for inhibiting powder adhesion to the wall by tilting and rotation: In the formula: The angle of inclination between the central axis of container (10) and the vertical direction. Let R be the rotational angular velocity of container (10), and R be the inner diameter of container (10). The coefficient of friction between the powder particles and the inner wall of the container (10) is given by g, where g is the acceleration due to gravity; the angle of inclination is given by g. The range is 20°-30°.

6. The DBD powder processing device based on three-dimensional turbulent mixing technology according to claim 2, characterized in that: The container (10) includes: mounting holes (1001), a reaction device shell (1002) and a reaction device inner wall (1003). The reaction device shell (1002) is provided with staggered mounting holes (1001) near the reaction device inner wall (1003) for fixing tungsten rods (11).

7. The DBD powder processing device based on three-dimensional turbulent mixing technology according to claim 1, characterized in that: The DBD powder processing device adopts coordinated control of in-tank stirring drive and overall tank drive. The in-tank motor is a first motor (802), which drives the stirring paddle (9) to generate shearing and disturbance inside the container tank (10). The out-of-tank motor is a second motor (13), which drives the container tank (10) to generate rotational disturbance. The first motor (802) and the second motor (13) have different rotational speeds.

8. A DBD powder processing method, based on the DBD powder processing device based on three-dimensional turbulent mixing technology according to any one of claims 1-7, characterized in that: Includes the following steps: An experimental platform was set up, a DBD reactor was installed, and the nanopowder to be treated was placed in the DBD reactor. Start the gas supply unit to continuously feed the working gas carrying the reaction medium into the DBD reactor, turn on the motor and adjust it to make the powder rotate and tumble evenly in the DBD reactor. Once a stable inert atmosphere is formed inside the DBD reactor, the monitoring unit is activated to match and adjust the power parameters until a stable discharge plasma is generated inside the plasma chamber. The power parameters are maintained to process the dynamic nanopowder at regular intervals. After the processing is completed, the motor and monitoring unit are turned off to terminate the plasma discharge. Then all gas supply is stopped, and the DBD powder processing device is allowed to cool naturally to complete the entire process.

9. A DBD powder processing method according to claim 8, characterized in that: The process of starting and adjusting the motor involves first starting the first motor (802), observing whether the stirring paddle (8) can stir the powder normally, and if it cannot stir normally, adjusting the parameters of the first motor (802). If it can stir normally, then starting the second motor (13) for adjustment.

10. A DBD powder processing method according to claim 8, characterized in that: The timed processing of the nanopowder to be processed in a dynamic state is as follows: When the first motor (802) and the second motor (13) start together, the hybrid cycle begins. At t=0, the second motor (13) starts to rotate forward while the first motor (802) rotates in reverse, and at that time... Synchronous commutation is performed at all times, so that the two motors are in sync. Then the second motor (13) reverses and the first motor (802) runs forward until... Finish.

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