Apparatus for manufacturing nanopowder using plasma and method for manufacturing nanopowder using same

Abstract

One embodiment of the present invention provides an apparatus for manufacturing nanopowder using plasma to which a preheating device for preheating a nanopowder precursor is coupled, and a method for manufacturing nanopowder with improved quality and increased production efficiency by preheating the nanopowder precursor using the apparatus.

Description

Nanopowder manufacturing device using plasma and nanopowder manufacturing method using the device

[0001] The present invention relates to a method for manufacturing nano powder using a plasma device, and more specifically, to a nano powder manufacturing device using plasma and a method for manufacturing nano powder using the device.

[0002]

[0003] With the electric vehicle market experiencing rapid growth, demand for batteries, a core component of EVs, continues to rise, leading to fierce global development efforts to improve battery performance. This performance enhancement, particularly in the context of anode materials, is crucial. Natural graphite, artificial graphite, and silicon have been used as anode materials. The industry is currently focusing on developing silicon anodes. Silicon offers approximately 10 times the unit energy capacity of graphite and a faster charging speed than graphite. Furthermore, it is abundant and environmentally friendly, offering numerous advantages.

[0004] In order to manufacture these silicon anode materials, silicon powder must be used. However, when using general silicon powder, there is a disadvantage in that the volume expands by up to 300% when charging, causing deformation of the battery. Therefore, research is being continuously conducted on methods of using nano silicon powder instead of general silicon powder.

[0005] However, there are chemical methods, physical methods, and plasma-based methods for manufacturing nano silicon powder. However, chemical methods have the disadvantage of secondary contamination and difficulty in mass production, and physical methods have limitations in the form of raw materials, making them difficult to commercialize.

[0006] In addition, in the method using plasma, especially the method of manufacturing nano silicon powder using multiple torches, the plasma speed is 500 m / s, the area of ​​3,000℃ or more involved in silicon vaporization is narrow at about 0.2 m, and the reaction time of silicon particles is 0.4X10 -3 Since it is a very short time (seconds), there is a disadvantage in that unreacted powder is generated due to insufficient reaction time.

[0007] This can result in a reduced yield in the production of nano-silicon powder, and the production of nano-silicon powder with poor quality due to the inclusion of unreacted powder. Therefore, there is a need for a method for producing high-quality nano-silicon powder without unreacted silicon powder that has not yet been converted to nano-silicon, and a device for doing so.

[0008]

[0009] [Prior Art Literature]

[0010] (Patent Document 1) Republic of Korea Patent Publication No. 10-2020-0056073

[0011]

[0012] The technical problem to be achieved by the present invention is to provide a nanopowder manufacturing device using plasma for preheating a nanopowder precursor.

[0013] The technical problem to be achieved by the present invention is to provide a method for manufacturing nano silicon powder without unreacted silicon powder by preheating silicon powder using a nano powder manufacturing device using plasma.

[0014] The technical problems to be solved by the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned can be clearly understood by a person having ordinary skill in the technical field to which the present invention belongs from the description below.

[0015]

[0016] In order to achieve the above technical task, one embodiment of the present invention provides a nanopowder manufacturing device using plasma.

[0017] In one embodiment of the present invention, the nanopowder manufacturing device using plasma may include a chamber section including a reaction section in which a plasma reaction occurs and a cooling section connected to the reaction section; an injection section coupled to the chamber section to inject a nanopowder precursor into the reaction section; a preheating section located outside the injection section to preheat the nanopowder precursor injected into the injection section; and a torch section connected to the chamber section to include a plurality of plasma torches that generate plasma in the reaction section.

[0018] In one embodiment of the present invention, the preheating unit may include a direct or indirect heating device using an induction heating device, a heater, or a torch.

[0019] In one embodiment of the present invention, the plurality of torches of the torch unit may be arranged radially at a certain interval based on the preheating unit.

[0020] In one embodiment of the present invention, the plurality of torches of the torch unit may be connected to the chamber unit at an angle of 10 to 50 degrees relative to the preheating unit.

[0021] In one embodiment of the present invention, the plurality of torches of the torch unit may include 2 to 6 torches.

[0022] In one embodiment of the present invention, the torch portion may be arranged to emit plasma toward the supply direction of the preheated nanopowder precursor, thereby creating a region where the plasma flame overlaps the reaction portion inside the chamber portion.

[0023] In one embodiment of the present invention, the preheated nanopowder precursor may be vaporized in a region where the plasma flame overlaps and then cooled in the cooling unit to produce the nanopowder.

[0024] In order to achieve the above technical task, another embodiment of the present invention provides a method for manufacturing nanopowder using a nanopowder manufacturing device using plasma.

[0025] In one embodiment of the present invention, a method for manufacturing a nanopowder using a nanopowder manufacturing device using plasma may include the steps of forming plasma in a reaction section of the chamber section using the torch section; injecting a nanopowder precursor into the injection section; preheating the nanopowder precursor injected into the injection section in the preheating section; and supplying the preheated nanopowder precursor to the reaction section of the chamber section so that the preheated nanopowder precursor is vaporized by the plasma and then cooled in the cooling section to manufacture the nanopowder.

[0026] In one embodiment of the present invention, the preheating temperature of the preheating unit may be 1000°C to 3000°C.

[0027] In one embodiment of the present invention, the preheating time of the preheating unit is 1.0X10 -2 1.0X10 seconds -3 It may include superhuman things.

[0028]

[0029] According to one embodiment of the present invention, a nanopowder manufacturing device using plasma capable of preheating a nanopowder precursor can be provided.

[0030] In addition, by preheating the nanopowder precursor according to one embodiment of the present invention, unreacted nanopowder precursor can be removed, thereby improving the quality and production yield of the nanopowder.

[0031] The effects of the present invention are not limited to the effects described above, and should be understood to include all effects that can be inferred from the detailed description of the present invention or the composition of the invention described in the claims.

[0032]

[0033] FIG. 1 is a cross-sectional view of a nanopowder manufacturing device using plasma according to one embodiment of the present invention.

[0034] FIG. 2 is a cross-sectional view of a torch section, a preheating section, and an injection section when viewed from above in a nanopowder manufacturing device using plasma according to one embodiment of the present invention.

[0035] FIG. 3 is a flowchart of a method for manufacturing nano silicon powder using a nano powder manufacturing device using plasma according to one embodiment of the present invention.

[0036] Figure 4 is an SEM image of nano silicon powder manufactured according to one embodiment of the present invention.

[0037] Figure 5 is an SEM image comparing nano silicon powders manufactured using non-preheated silicon powder and preheated silicon powder.

[0038]

[0039] Hereinafter, the present invention will be described with reference to the attached drawings. However, the present invention can be implemented in various different forms and is therefore not limited to the embodiments described herein. In the drawings, irrelevant parts have been omitted for clarity of description, and similar parts have been designated with similar reference numerals throughout the specification.

[0040] Throughout the specification, when a part is said to be "connected (connected, contacted, or coupled)" to another part, this includes not only cases where it is "directly connected," but also cases where it is "indirectly connected" with another part in between. Furthermore, when a part is said to "include" a component, this does not exclude other components, but rather implies that it may include other components, unless otherwise specifically stated.

[0041] The terminology used herein is merely used to describe specific embodiments and is not intended to limit the present invention. The singular expression includes the plural expression unless the context clearly indicates otherwise. In this specification, it should be understood that the terms "comprises" or "has" indicate the presence of a feature, number, step, operation, component, part, or combination thereof described in the specification, but do not exclude in advance the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0042] Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings.

[0043]

[0044] A nanopowder manufacturing device using plasma according to one embodiment of the present invention is described.

[0045] FIG. 1 is a cross-sectional view of a nanopowder manufacturing device (100) using plasma according to one embodiment of the present invention.

[0046] Referring to the above drawing 1, the plasma-using nanopowder manufacturing device (100) according to one embodiment of the present invention may include a chamber section (110) including a reaction section (120) in which a plasma reaction occurs inside and a cooling section (160) connected to the reaction section (120); an injection section (130) coupled to the chamber section (110) to inject a nanopowder precursor into the reaction section (120); a preheating section (140) located outside the injection section (130) to preheat the nanopowder precursor injected into the injection section (130); and a torch section (150) including a plurality of plasma torches connected to the chamber section (110) to generate plasma in the reaction section (120).

[0047] At this time, the preheating unit (120) may include a direct or indirect heating device using an induction heating device, heater, or torch.

[0048] In the above plasma-using nanopowder manufacturing device, plasma is generated by generating an electric arc between a cathode and an anode nozzle and contacting gas to cause collisions of dissociated gas ions.

[0049] At this time, the plasma generates a direct current arc discharge and passes an inert gas at high speed, forming a plasma jet and reaching a central temperature of approximately 6,000 K.

[0050] The torch used in the nanopowder manufacturing device using plasma according to one embodiment of the present invention is a non-transferred type that forms a plasma arc in an internal electrode, and the non-transferred plasma torch is used to utilize high-temperature thermal energy. When the heat within the non-transferred plasma is used to increase the temperature of a metal material above its vaporization temperature, the metal material vaporizes.

[0051] Vaporized metal materials are formed into nanopowders during the cooling process. This principle can be applied not only to metals but also to various fields, such as the decomposition of organic substances and the spheroidization of ceramic powders.

[0052] The plurality of torches of the above torch unit (150) may be arranged radially at a certain interval based on the preheating unit (140).

[0053] FIG. 2 is a cross-sectional view of a torch section (150), a preheating section (140), and an injection section (130) when viewed from above in a nanopowder manufacturing device (100) using plasma according to one embodiment of the present invention.

[0054] Referring to the above drawing 2, the plurality of torches of the torch unit (150) may be arranged in a radial arrangement at a certain interval based on the preheating unit (140).

[0055] At this time, the inside of the preheating unit (140) in the above-described Fig. 2 may include a form in which an injection unit (130) is arranged.

[0056] The plurality of torches of the above torch section (150) may be connected to the chamber section (110) at an angle of 10 to 50 degrees with respect to the preheating section (140).

[0057] At this time, if the torch part (150) is inclined at an angle of less than 10 degrees with respect to the preheating part (140), there may be a problem in that the heat energy from the plasma cannot be concentrated, and thus the desired vaporization temperature cannot be reached. If it exceeds 50 degrees, there may be a problem in that the heat frames from each plasma interfere with each other, causing damage to the tip of the torch. Therefore, preferably, the torch part (150) may include one having an angle of 15 to 45 degrees with respect to the preheating part (140).

[0058] The plurality of torches of the above torch unit (150) may include 2 to 6 torches.

[0059] Next, the torch section (150) may include creating an area where a plasma flame overlaps the reaction section (120) inside the chamber section (110) diagonally downward toward the supply direction of the preheated nanopowder precursor.

[0060] In addition, the preheated nanopowder precursor may be vaporized in an area where the plasma flame overlaps and then cooled in the cooling unit (160) to produce the nanopowder.

[0061] At this time, the process of manufacturing nanopowder by cooling the vaporized nanopowder precursor is as follows: when the nanopowder precursor powder passes into the high-temperature plasma and reaches a temperature higher than the vaporization temperature of the nanopowder precursor, the nanopowder precursor vaporizes. When the nanopowder precursor vaporizes, nucleation occurs, and the vaporized nanopowder precursor grows around the nucleus, and the size of the nanopowder is determined by controlling the cooling rate during the growth process of the nanopowder precursor.

[0062]

[0063] A method for manufacturing nanopowder using a nanopowder manufacturing device using plasma according to another embodiment of the present invention is described.

[0064] Figure 3 is a flowchart showing a nanopowder manufacturing method according to one embodiment of the present invention.

[0065] As shown in FIG. 3, a method for manufacturing a nanopowder using a nanopowder manufacturing device using plasma may include a step of forming plasma in a reaction section of the chamber section using the torch section (S100); a step of injecting a nanopowder precursor into the injection section (S200); a step of preheating the nanopowder precursor injected into the injection section in the preheating section (S300); and a step of supplying the preheated nanopowder precursor to the reaction section of the chamber section so that the preheated nanopowder precursor is vaporized by the plasma and then cooled in the cooling section to manufacture the nanopowder (S400).

[0066] In the first step, a step of forming plasma in the reaction section of the chamber section using the torch section may be included. (S100)

[0067] At this time, the plasma temperature may include 2500°C to 6000°C.

[0068] In the second step, a step of injecting a nanopowder precursor into the injection unit may be included. (S200)

[0069] In the third step, a step of preheating the nanopowder precursor injected into the injection unit in the preheating unit may be included. (S300)

[0070] At this time, the preheating temperature of the preheating unit may be 1000°C to 6000°C, and preferably, the preheating temperature of the preheating unit may be 1000°C to 3000°C.

[0071] At this time, the reason for the preferable temperature range is that if the preheating temperature of the preheating section is less than 1000°C, there may be a problem that unreacted nano-powder precursors exist, and if it exceeds 3000°C, a phenomenon of vaporization of the nano-powder precursors occurs in the preheating section, and at this time, clinkers grow at the tip and head of the torch, causing abnormal occurrence of the torch, which interferes with the continuity and uniformity of the nano-reaction, and a problem may occur in which silicon aggregates (clinker) are generated at the tip of the preheating section torch, causing the heating section torch to become clogged.

[0072] In the final step, the step of supplying the preheated nanopowder precursor to the reaction section of the chamber section, vaporizing the preheated nanopowder precursor by the plasma, and then cooling it in the cooling section to manufacture the nanopowder may be included. (S400)

[0073]

[0074] Hereinafter, the present invention will be described in more detail through examples. These examples are intended solely to illustrate the present invention, and the scope of the present invention is not limited by these examples.

[0075]

[0076] <Example>

[0077] First, a preheating torch was used as a preheating part, and the power of all three torches in the preheating part and the torch part was 30 kW (150 A, 200 V).

[0078] Silicon powder was used as a nanopowder precursor. To preheat the silicon powder, the preheating temperature was 1000℃, which is 1.0X10 -2 1.0X10 seconds -3 Heating was performed for sec, and the temperature of the plasma torch was set to 3000℃ or higher.

[0079] The carrier gas was nitrogen, the gas flow rate was 5 LPM, and silicon powder was injected into the injection unit at a rate of 5 kg / hr to produce nanosilicon powder.

[0080]

[0081] <Comparative Example>

[0082] Nano silicon powder was manufactured under the same conditions as in the above example, but with a configuration excluding the preheating section.

[0083]

[0084] <Experimental Example>

[0085] The nano silicon powder manufactured in the above example and the nano silicon powder manufactured in the above comparative example were observed using SEM and compared.

[0086]

[0087] Figure 4 is an image of nano silicon powder manufactured according to the above example observed using SEM.

[0088] In the above Fig. 4, (a) is an image of nano silicon powder manufactured from preheated silicon powder at a magnification of x10k, and (b) is an image of nano silicon powder manufactured from preheated silicon powder at a magnification of x30k.

[0089] Referring to the above FIG. 4, when manufacturing nano silicon powder according to the above embodiment using a nano powder manufacturing device using plasma according to one embodiment of the present invention, it can be confirmed that most of the silicon powder is vaporized.

[0090]

[0091] Figure 5 is an SEM image comparing nano silicon powders manufactured using non-preheated silicon powder and preheated silicon powder.

[0092] Referring to the above Figure 5, (a) in the case of nano silicon powder manufactured from silicon powder that has not been preheated, large lumps of silicon particles can be confirmed by looking at the area marked with a red circle.

[0093] At this time, it can be seen that the large lumps of silicon particles are silicon powder that has not been vaporized into nano silicon powder, and a large amount of silicon powder has not been vaporized into nano silicon powder.

[0094] In the case of nano silicon powder manufactured from preheated silicon powder in Fig. 5 (b), it can be seen that most of the silicon powder has vaporized and no large silicon particles are observed, which confirms that most of the preheated silicon powder that was introduced has vaporized and become nano silicon powder.

[0095]

[0096] Through this, it can be confirmed that when a nanopowder is manufactured using a nanopowder precursor that has been preheated using a nanopowder manufacturing device using plasma according to one embodiment of the present invention, it is possible to manufacture high-quality nanopowder, and it can be confirmed that the yield of nanopowder manufacturing can also be improved through this.

[0097]

[0098] The foregoing description of the present invention is for illustrative purposes only, and those skilled in the art will readily appreciate that the present invention can be readily modified into other specific forms without altering the technical spirit or essential characteristics of the present invention. Therefore, the embodiments described above should be understood as illustrative in all respects and not restrictive. For example, each component described as a single entity may be implemented in a distributed manner, and similarly, components described as distributed may be implemented in a combined manner.

[0099] The scope of the present invention is indicated by the claims described below, and all changes or modifications derived from the meaning and scope of the claims and their equivalent concepts should be interpreted as being included in the scope of the present invention.

[0100]

[0101] [Explanation of symbols]

[0102] 100: Nanopowder manufacturing device using plasma

[0103] 110: Chamber

[0104] 120: Reaction section

[0105] 130: Injection part

[0106] 140: Preheating section

[0107] 150: Torch Department

[0108] 160: Cooling section

Claims

1. A chamber section including a reaction section in which a plasma reaction occurs inside and a cooling section connected to the reaction section; An injection unit coupled to the chamber unit and injecting a nanopowder precursor into the reaction unit; A preheating unit located outside the injection unit to preheat the nanopowder precursor injected into the injection unit; and A nanopowder manufacturing device using plasma, characterized in that it includes a torch section including a plurality of plasma torches that are connected to the chamber section and generate plasma in the reaction section.

2. In paragraph 1, A nanopowder manufacturing device using plasma, characterized in that the above preheating unit includes a direct or indirect heating device using an induction heating device, a heater or a torch.

3. In paragraph 1, A nano-powder manufacturing device using plasma, characterized in that the plurality of torches of the above torch section are arranged radially at a certain interval based on the above preheating section.

4. In paragraph 1, A nanopowder manufacturing device using plasma, characterized in that the plurality of torches of the torch section are connected to the chamber section at an angle of 10 to 50 degrees relative to the preheating section.

5. In paragraph 1, A nanopowder manufacturing device using plasma, characterized in that the plurality of torches of the torch section are composed of 2 to 6 torches.

6. In paragraph 1, A nanopowder manufacturing device using plasma, characterized in that the torch section is arranged to emit plasma toward the supply direction of the preheated nanopowder precursor, thereby creating a region where the plasma flame overlaps the reaction section inside the chamber section.

7. In paragraph 1, A nanopowder manufacturing device using plasma, characterized in that the above-mentioned preheated nanopowder precursor is vaporized in the reaction section and then cooled in the cooling section to manufacture nanopowder.

8. In the method for manufacturing nano powder using the nano powder manufacturing device using plasma of Article 1, A step of forming plasma in the reaction section of the chamber section using the torch section; A step of injecting a nanopowder precursor into the injection unit; A step of preheating the nanopowder precursor injected into the injection unit in the preheating unit; and A method for manufacturing a nanopowder using a plasma-based nanopowder manufacturing device, characterized in that it comprises a step of supplying the preheated nanopowder precursor to a reaction section of the chamber section, vaporizing the preheated nanopowder precursor by the plasma, and then cooling it in the cooling section to manufacture a nanopowder.

9. In paragraph 8, A method for manufacturing nanopowder using a nanopowder manufacturing device using plasma, characterized in that the preheating temperature of the above preheating section is 1000°C to 3000°C.

10. In paragraph 8, The preheating time of the above preheating section is 1.0X10 -2 1.0X10 seconds -3 A method for manufacturing nanopowder using a nanopowder manufacturing device using plasma characterized by being super.

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