Plasma powder modification device based on venturi effect

Abstract

The utility model relates to a kind of plasma powder modification device based on venturi pipe synergism, comprising: plasma generator, it is used to produce active plasma;Venturi pipe, the import of venturi pipe is connected the outlet of plasma generator, and the throat of venturi pipe is provided with powder feeding port;Powder supply assembly, it is used to deliver powder to powder feeding port;Collection component, collection component connects the outlet of venturi pipe.The plasma powder modification device provided by the utility model, when plasma flows through venturi pipe, speed reaches highest at throat, static pressure drops to minimum, powder is injected from throat, is accelerated and dispersed instantly, simultaneously, due to the strong turbulence and shear force generated by venturi effect, can effectively scatter the agglomerated powder, so that powder is in the form of single particle or close to single particle and high-energy plasma is fully contacted, realizes the synergistic effect of "plasma activation" and "flow field dispersion".

Description

Technical Field

[0001] This utility model belongs to the field of powder material surface modification technology, and specifically relates to a plasma powder modification device based on Venturi tube enhancement. Background Technology

[0002] Plasma technology, as a dry, environmentally friendly, and efficient surface treatment method, has been widely used in the surface modification of powder materials, such as improving the dispersibility, compatibility, catalytic activity, or altering their hydrophilicity / hydrophobicity.

[0003] Traditional plasma batch processing equipment for powders suffers from problems such as uneven processing, easy powder agglomeration, and low modification efficiency. While existing plasma fluidization processing devices achieve continuous processing, they often face technical bottlenecks such as insufficient plasma-powder contact, short reaction time, and low energy utilization.

[0004] The Venturi tube, a common fluid dynamics component, can generate a high-speed, low-pressure flow field at its throat, and is often used for powder conveying and mixing. However, there has been no innovative and in-depth integration of the Venturi tube structure with a plasma generator. Utility Model Content

[0005] In view of this, the purpose of this utility model is to address the shortcomings of the existing technology by providing a plasma powder modification device based on Venturi tube enhancement, which utilizes the unique flow field characteristics of the Venturi tube to enhance the effect of plasma on powder modification.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: A plasma powder modification device based on Venturi tube enhancement includes: Plasma generator, used to produce active plasma; The Venturi tube has its inlet connected to the outlet of the plasma generator, and a powder feed inlet is provided at the throat of the Venturi tube. A powder supply assembly for conveying powder to a powder inlet; Collect components; collect components connect to the outlet of the venturi tube.

[0007] To better realize this utility model, the above structure is further optimized, and the ratio of the inner diameter of the venturi throat to the inner diameter of the inlet is 1:1.5 to 1:4.

[0008] To better realize this utility model, the above structure is further optimized, and the angle between the axis of the powder feed inlet and the axis of the venturi tube is 70° to 110°.

[0009] To better realize this utility model, the above structure is further optimized, and the plasma generator is an atmospheric pressure plasma spray gun.

[0010] To better realize this utility model, the above structure is further optimized. The powder supply component includes a hopper and a metering conveyor. The metering conveyor is used to transport the powder in the hopper to the powder inlet.

[0011] To better realize this utility model, the above structure is further optimized. The collection component includes a gas-solid separator and a dust collector connected in sequence, and the outlet of the venturi tube is connected to the inlet of the gas-solid separator.

[0012] To better realize this utility model, the above structure is further optimized, and the gas-solid separator is a cyclone separator.

[0013] To better realize this utility model, the above structure is further optimized, and the dust collector is driven by an induced draft fan.

[0014] Compared with the prior art, this utility model has the following advantages: The plasma powder modification device provided by this invention achieves its highest velocity and lowest static pressure at the throat when the plasma flows through the Venturi tube. After the powder is injected from the throat, it is instantly accelerated and dispersed. At the same time, the strong turbulence and shear force generated by the Venturi effect effectively break up the agglomerated powder, allowing the powder to fully contact the high-energy plasma in the form of single particles or near-single particles, thus achieving a synergistic effect of "plasma activation" and "flow field dispersion". Meanwhile, the high-speed flow ensures that the collision frequency and energy transfer efficiency between the powder and the active particles (electrons, ions, free radicals) in the plasma are greatly improved, thereby significantly enhancing the surface reaction kinetics. The powder is introduced into the throat region where the plasma energy density is the highest, achieving precise and efficient use of energy and avoiding energy waste. The high-speed airflow can prevent the modified powder from depositing and scaling on the reaction chamber wall, ensuring the long-term stable operation of the device and overcoming the shortcomings of traditional equipment that are prone to clogging. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of this utility model 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 utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is one of the structural schematic diagrams of the plasma powder modification device of this utility model; Figure 2 yes Figure 1 A magnified schematic diagram of the structure of part A in the diagram; Figure 3 This is the second schematic diagram of the structure of the plasma powder modification device of this utility model.

[0017] In the picture: 1-Plasma generator, 2-Venturi tube, 201-Powder inlet, 3-Hopper, 4-Quantitative conveyor, 5-Gas-solid separator, 6-Dust collector, 7-Exhaust fan. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions of this utility model will be described in detail below. Obviously, the described embodiments are only a part of the embodiments of this utility model, and not all of them. Based on the embodiments of this utility model, all other implementation methods obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0019] In the description of this utility model, it should be noted that, unless otherwise stated, "a plurality of" means two or more; the terms "upper," "lower," "left," "right," "inner," "outer," "front end," "rear end," "head," "tail," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0020] In the description of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0021] Please refer to Figures 1-3 The present invention provides a plasma powder modification device based on Venturi tube enhancement, comprising a plasma generator 1, a Venturi tube 2, a powder supply component and a collection component.

[0022] The plasma generator 1 is used to generate active plasma. In this embodiment, the plasma generator 1 is an atmospheric pressure plasma gun, and its working gas is one or more of argon, nitrogen, oxygen, methane, and carbon tetrafluoride. Preferably, argon is used as the main working gas, with a small amount of oxygen mixed in as the reaction gas. Furthermore, this device can introduce corresponding functional groups onto the powder surface by changing the plasma working gas (such as O2, N2, CF4, etc.), achieving different modification requirements such as hydrophilicity, hydrophobicity, nitriding, and fluorination, thus having wide applicability. The venturi tube 2 has its inlet connected to the outlet of the plasma generator 1, and its throat is equipped with a powder inlet 201. The ratio of the inner diameter of the throat to the inner diameter of the inlet of the venturi tube 2 is 1:1.5 to 1:4, preferably 1:2.5. The angle between the axis of the powder inlet 201 and the axis of the venturi tube 2 is 70° to 110°, with a 90° vertical angle ensuring that the powder slides smoothly downwards.

[0023] The powder supply assembly, which is used to convey powder to the powder inlet 201, as shown in the attached figure, includes a hopper 3 and a metering conveyor 4. The metering conveyor 4 is used to convey the powder in the hopper 3 to the powder inlet 201. The metering conveyor 4 can be a vibrating feeder, a venturi feeder or a screw conveyor, etc., to continuously and stably convey the calcium carbonate powder to be modified to the throat of the venturi tube 2.

[0024] The collection assembly includes a gas-solid separator 5 and a dust collector 6 connected in sequence. The outlet of the venturi tube 2 is connected to the inlet of the gas-solid separator 5. The gas-solid separator 5 is a cyclone separator, but other gas-solid separation devices such as bag filters or electrostatic collectors can also be used. The dust collector 6 is driven by an induced draft fan 7. The cyclone separator provides primary separation, collecting a portion of the modified powder in advance to reduce the working pressure on the subsequent dust collector 6. The dust collector 6, as the final stage, needs to ensure complete separation of the powder and gas, so that the gas is discharged under the traction of the induced draft fan 7, leaving only the modified powder.

[0025] During operation, the argon / oxygen plasma jet enters the inner cavity of the Venturi tube 2 at high speed, forming a high-speed, low-pressure zone at the throat. The calcium carbonate powder to be modified is drawn in here and is instantly dispersed and entrained by the high-speed airflow. It reacts violently with high-energy particles and reactive oxygen free radicals in the plasma, introducing hydroxyl and carboxyl groups onto its surface to achieve hydrophilic modification. The modified powder and the exhaust gas are discharged from the outlet of the Venturi tube 2 and enter the cyclone separator for gas-solid separation. Finally, it enters the dust collector 6 to collect the hydrophilic calcium carbonate product.

[0026] Tests showed that calcium carbonate powder treated with this device had its contact angle in water reduced from the original 125° to below 25°, with uniform modification and no large particle agglomerates. Compared with traditional drum-type plasma modification equipment, the processing efficiency is increased by about 3 times and energy consumption is reduced by about 40% while achieving the same modification effect.

[0027] Furthermore, this utility model also provides a method for modifying plasma powder using the above-mentioned device, comprising the following steps: S1: Start the plasma generator to produce a plasma jet, which flows through the reaction chamber of the venturi tube; S2: The powder to be modified is injected from the throat of the venturi tube through the powder supply assembly; S3: The powder undergoes intense and uniform mixing and reaction with the plasma in the high-velocity, highly turbulent region of the venturi throat, thus completing the surface modification. S4: The gas-solid mixture after the reaction is discharged through the collection component and collected.

[0028] Furthermore, in step S1, the energy and chemical activity of the plasma can be controlled by adjusting the power, gas type, and flow rate of the plasma generator. The powder to be modified is one of inorganic powder, metal powder, polymer microspheres, or carbon material.

[0029] The above description is merely a specific embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the protection scope of the claims.

Claims

1. A plasma powder modification device based on Venturi tube enhancement, characterized in that, include: Plasma generator (1), which is used to generate active plasma; Venturi tube (2), the inlet of which is connected to the outlet of the plasma generator (1), and the throat of the Venturi tube (2) is provided with a powder feed inlet (201). A powder supply assembly for conveying powder to the powder inlet (201). A collection component is connected to the outlet of the venturi tube (2).

2. The plasma powder modification device based on Venturi tube enhancement according to claim 1, characterized in that: The ratio of the inner diameter of the throat to the inner diameter of the inlet of the Venturi tube (2) is 1:1.5 to 1:

4.

3. The plasma powder modification device based on Venturi tube enhancement according to claim 2, characterized in that: The angle between the axis of the powder inlet (201) and the axis of the venturi tube (2) is 70° to 110°.

4. The plasma powder modification device based on Venturi tube enhancement according to claim 1, characterized in that: The plasma generator (1) is an atmospheric pressure plasma spray gun.

5. The plasma powder modification device based on Venturi tube enhancement according to claim 1, characterized in that: The powder supply assembly includes a hopper (3) and a metering conveyor (4), the metering conveyor (4) being used to convey the powder in the hopper (3) to the powder inlet (201).

6. A plasma powder modification device based on Venturi tube enhancement according to any one of claims 1-5, characterized in that: The collection assembly includes a gas-solid separator (5) and a dust collector (6) connected in sequence, with the outlet of the venturi tube (2) connected to the inlet of the gas-solid separator (5).

7. The plasma powder modification device based on Venturi tube enhancement according to claim 6, characterized in that: The gas-solid separator (5) is a cyclone separator.

8. The plasma powder modification device based on Venturi tube enhancement according to claim 6, characterized in that: The dust collector (6) is driven by an induced draft fan (7).

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