KR100977459B1

KR100977459B1 - Method and system for mass production of nanopowders by wire explosion in liquid

Info

Publication number: KR100977459B1
Application number: KR1020070115165A
Authority: KR
Inventors: 조주현
Original assignee: 한국전기연구원
Priority date: 2007-11-13
Filing date: 2007-11-13
Publication date: 2010-08-24
Also published as: KR20090049104A

Abstract

The present invention relates to a method and system for mass production of nanopowders by electric explosion in liquid, and more particularly, to mass production of nanopowders using various types of explosives, and to prevent the feeding part from being damaged by an electric explosion. The structure of the high voltage electrode is made in the form of a staircase conical container so that explosive materials of various shapes and lengths can be seated between the high voltage electrodes without slipping, and the colloidal liquid generated during the electric explosion is concentrated to reintroduce the liquid into the lower chamber. It relates to a method and system for mass production of nanopowders.

Therefore, the present invention repeatedly supplies the rod-shaped explosive material to the electrode part by using a robot arm and a rotating machine, and concentrates and reintroduces the colloidal liquid ejected during the electric explosion by using the concentrator and the circulator. Provided are a method and system for mass production of nanopowders by electroexplosion in liquids for recycling liquids.

Nano powder, electric explosion, colloid, high voltage electrode, robot arm, motor, circulation, concentration, mass production

Description

Method and System for Mass Production of Nanopowders by Wire Explosion in Liquid

Recently, the development of nanostructured powder materials as a new material has been very important because it can be applied as a foundation technology in a new field including nano devices.

The ultra fine powder material can exhibit unusual electro-magnetic, mechanical, and catalytic properties that cannot be obtained with conventional materials due to the finer material structure (100 nm or less) and the increase in surface area. Therefore, ultra-high strength parts, magnetic parts, Next-generation functional materials, such as thermoelectrics, sensors, filters, and catalysts, must create new demand throughout the industry.

With the development of the high-tech industry, the performance and miniaturization of components and systems are progressing. Currently, component factors having a phenomenological length of micron or submicron, which determine physical / chemical / biological characteristics, are used.

Therefore, the importance of nanotechnology is a technology that can overcome the limitations of the existing technology for high performance and miniaturization of parts and systems, and it is typical and cutting-edge of future technology because new performance can be expressed as the phenomenological length decreases. It is an essential element in product development.

At present, a variety of methods are known for producing a material from nanopowders, but among them, metal nanopowder manufacturing technology by an electric explosion method using pulse power is widely known and is being actively researched.

The nanopowder manufacturing method using pulse power not only has a very important meaning in terms of industrial applications, but is also economically advantageous compared to other methods of preparing nanopowders.

Here, look at the conventional metal nano powder manufacturing method by the electric explosion method using pulse power as follows.

Existing metal nanopowder manufacturing method using an electroexplosion method in the air, providing a predetermined chamber filled with air or an inert gas; Feeding a metal wire into the chamber; Electrically exploding and vaporizing the metal wire in the chamber using pulse power; Including the step of collecting the metal nano-powder generated by cooling / condensation by the atmosphere gas using an air filter, and the like.

However, the nano-powder manufacturing method by the conventional air-explosion method that proceeds to the above process has the following problems.

First, most metal nanopowders are exposed to air in the process of collection and handling and are easily oxidized, and there is a risk of dust explosion in the process, which makes handling difficult.

Second, in the nano powder manufacturing process, there is an inconvenience of having to regularly clean the deposited powder due to frequent breakdown due to the powder deposited inside the chamber, and accordingly, productivity and workability are greatly reduced.

Third, the nanoparticles collected in the air tend to aggregate due to their characteristics, which makes it difficult to classify them by size.

Fourth, in order to use the agglomerated powder, since an essential step of dispersing the nanopowder in the dispersant is further required, there is an inefficient and inefficient economic aspect.

In order to supplement the conventional method for manufacturing nanopowders by the airborne explosion method, a method for preparing nanopowders by the liquid explosion method has been proposed.

The nanopowder manufacturing method by the electrolytic explosion in the liquid has the advantage that the conventional manufacturing method in terms of the quality of the powder, but has a problem that is difficult to mass production.

Specifically, the method for manufacturing nanopowders in air and in liquid feeds wires between electrodes in a manner of rolling a thin wire of 1 mm or less, and such a roll feeding method is that deformation of wires due to shock waves in the case of explosion in liquid There is a problem that continuous feeding is impossible to occur.

Therefore, the nano-powder manufacturing method by the liquid explosion method is difficult to be applied to mass production when using the feeding method used in the conventional lifting method because the gap between the wire and the electrode is much smaller than the lifting method can be exploded.

The present invention has been made in order to solve the above problems, to overcome the limitations of the production volume that could not be overcome in the conventional nano-powder by liquid explosion in order to implement a mass production system applicable to industries such as powder metallurgy The rod-shaped explosive material is repeatedly supplied to the electrode part by the feeding part operation, and then the electrolytic explosion of the explosive material seated on the conical stepped high voltage electrode, and the colloid generated by the electric explosion of the explosive material. It is an object of the present invention to provide a method and a system for mass production of nanopowders by electroexplosion in a liquid in which a liquid is concentrated in a concentrator and re-introduced into a lower chamber where an electroexplosion occurs.

The present invention for achieving the above object

A slot installed at an upper end of the upper chamber and loaded with explosive material conveyed by a conveyor; A feeding unit disposed below the slot to drop the explosive material; A lower chamber in which the feeding part is mounted on the upper part and the inside of which is filled with liquid; A sliding door disposed below the feeding part to isolate the feeding part from the following electrode part; An electrode unit mounted at a lower portion of the lower chamber to electrically explode the explosive material seated by the feeding unit; An explosion device comprising;

A storage container made of a transparent material for temporarily storing a colloid ejected by an electric explosion; A collecting tube connected to one side of the lower chamber to communicate the lower chamber with a storage container; An inlet control valve connected to one side of the storage container to adjust an inflow amount of the colloid; A concentrating unit for concentrating the colloid introduced from the storage container; Concentrating device consisting of;

A circulation pipe communicating the concentrating device and the lower chamber; A flow control valve and a circulation motor installed in the circulation pipe to control the flow rate and speed of the concentrated colloid re-introduced into the lower chamber; A circulation device consisting of;

And a control unit.

In addition, the feeding unit includes a drive motor, but a rotor installed on the upper end of the lower chamber; A robot arm mounted on both sides of the rotator to mount and detach the explosive material using an electromagnet;

And a control unit.

In addition, the electrode portion is a high-voltage electrode formed in the form of a stepped conical container; An electrode support disposed under the high voltage electrode to insulate and support the high voltage electrode;

And a control unit.

And, the concentrating portion and the liquid container for storing the colloidal liquid controlled to be introduced by the inlet control valve; A heating unit installed at one side of the liquid container to heat the colloidal liquid; A condenser mounted on an upper portion of the liquid container to cool and liquefy colloidal vapor evaporated by the heating unit; A condensation vessel installed at a lower portion of the condenser to store the particle separation liquid liquefied by the condenser, and being connected to the circulation pipe;

And a control unit.

In another preferred embodiment,

(a) dropping the explosive material loaded in the slot by operation of the feeding part and seating the explosive material on the electrode part;

(b) closing the sliding door provided between the feeding part and the electrode part to isolate the electrode part and the feeding part from the electric power generation;

(c) supplying pulse power to the high voltage electrode to electroexplode the explosive material seated on the electrode in a liquid-filled lower chamber;

(d) storing the colloidal liquid ejected by the electric explosion in the storage container through the collection tube;

(e) separating the colloidal liquid introduced into the proper amount by the inflow control valve from the reservoir using a concentrating unit;

(h) reflowing the liquid separated by the concentrator into the lower chamber using a circulator;

And a control unit.

In addition, the explosive material is characterized by using a rod shape cut to a certain length.

In the step (a), the explosion material loaded in the slot is mounted and detached using an electromagnet-attached robot arm, and the robot arm operates the driving motor while the process of loading and discharging the explosion material is repeated. Rotate to.

In addition, the step (e) is a step of storing the colloid introduced into the appropriate amount by the inlet control valve in the liquid container; Heating and evaporating the colloidal solution stored in the liquid container with a heating unit; Cooling and liquefying the evaporated colloid with a coagulant; Storing the liquid separated from the liquid due to the liquefaction in a concentration vessel;

And a control unit.

As described above, the method and system for mass production of nanopowders by submerged electroexplosion according to the present invention provide the following effects.

First, by supplying the explosive material to the electrode part repeatedly by using the feeding part provided with the robot arm and the driving motor, various types of explosive materials can be used, and it is also possible to mass-produce nanopowders,

After the explosive material is supplied to the lower chamber, the sliding door is closed to isolate the feeding portion and the electrode portion, thereby preventing the feeding portion from being damaged from the impact caused by the electric explosion.

The structure of the high voltage electrode is made in the form of a staircase conical container, and the explosive materials of various shapes and lengths are seated between the high voltage electrodes without slipping,

By concentrating the colloidal liquid generated during the electric explosion using a concentrator, to produce a particle separation liquid in which the particulate matter is separated,

By reflowing the particle separation liquid into the lower chamber using a circulator, there is an effect of minimizing the loss of the liquid to be filled during the electrical explosion inside the lower chamber.

The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting of the present invention. A singular expression includes a plural expression unless the context clearly indicates otherwise. In this application, the terms “comprises” or “having” are intended to indicate that there is a feature, number, step, action, component, part, or combination thereof described in the specification, and one or more other It is to be understood that the present invention does not exclude the possibility of the presence or the addition of features, numbers, steps, operations, components, components, or a combination thereof.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a view showing a nanopowder mass production system by electric explosion in liquid according to the present invention, and FIG. 2 is a view showing an explosive device of FIG. 1.

According to the present invention, after the rod-shaped explosive material 160 is repeatedly supplied to the electrode part 110 by the feeding part 100 operation, the explosive material 160 seated on the high voltage electrode 111 having a conical step shape. Electrolytically explode and concentrate the colloidal liquid generated by the electrical explosion of the explosive material 160 with the concentrator 20 (separation of particles from the colloidal liquid) and reflow into the lower chamber 120 in which the electrical explosion occurs. Provided is a submerged electroexplosion system that makes it possible to produce powder in large quantities.

The detailed description of each component of the nanopowder mass production system by the electric explosion in the liquid of the present invention will be described in detail with reference to the method of manufacturing the nanopowder.

As shown in Figure 1, the nano-powder mass production system by the electric explosion in the liquid according to the present invention is largely exploded material 160 is repeatedly supplied by the explosion apparatus 10 and the electrical explosion is ejected by the electrical explosion Concentrator 20, the colloid is concentrated, and the circulation device 30 for re-introducing the concentrated colloid.

The explosive device 10 has a slot 140 is installed on the upper end of the upper chamber 120 having an empty space therein is loaded with the explosive material 160 transported by a conveyor (not shown), the loaded explosive material 160 is dropped to the electrode unit 110 by the operation of the feeding unit 100.

At this time, the explosive material 160 has a diameter of about 0.5mm ~ 2mm, it is loaded in the slot 140 while being formed in the shape of a rod cut into a predetermined length by the driving of the robot arm 101 and the rotor 104 By being repeatedly supplied to the high voltage electrode 111, the conventional wire is fed in a roll feeding manner in a liquid explosion to compensate for the difficulty in continuous feeding.

In addition, the feeding unit 100 rotates the robot arm 101 and the robot arm 101 in the center and the robot arm 101 to take out and drop the explosive material 160 using the electromagnet 102 in the lower portion of the slot 140. It consists of a rotor 104 including a rotating shaft and a drive motor 103.

The rotary machine 104, which is the center of the feeding unit 100, is mounted on an upper portion of the lower chamber 120 (stainless steel material) disposed under the upper chamber 120, and a sliding door is disposed inside the lower chamber 120. 150 is installed to isolate the feeding unit 100 and the electrode unit 110 during the electrical explosion.

The interior of the lower chamber 120 is filled with a certain space of the liquid 113 (organic solvent such as distilled water, alcohol, etc.), the electrode portion 110 is installed in the liquid 113 is seated by the feeding unit 100 The explosive material 160 is electroexploded.

Here, the electrode unit 110 has a structure of a high voltage electrode 111 in the form of a conical stepped container to prevent slipping when the explosive material 160 falls, and the explosive material 160 having various lengths and shapes fails without fail. In order to be seated between, the high voltage electrode 111 uses the high voltage and the ground electrode to allow the explosive material 160 to fall from the feeding unit 100 to be safely contacted with the electrode.

In addition, the high voltage electrode 111 has an electrode support 112 made of Teflon material at the bottom thereof to insulate and support the high voltage electrode 111, and is connected to a separate capacitor by a cable.

That is, as shown in Figure 2, the high voltage electrode 111 is inserted into the electrode support 112 is fixed to the inside of the lower chamber 120, the cross section of the stepped surface of a constant depth as the inside enters from both sides This forms a symmetrical structure.

Hereinafter, referring to the accompanying drawings, the operation of the explosion apparatus will be described.

3 is an operation diagram of the feeding unit according to the present invention.

First, as shown in FIG. 3, the explosive material 160 loaded into the slot 140 by a magnetic force generated by supplying current to the electromagnet 102 attached to the robot arm 101a on one side of the rotor 104. ), The robot arm 101 is rotated 180 degrees around the rotation axis by the operation of the drive motor 103, so that the robot arm 101a to which the explosive material 160 is attached is placed on the high voltage electrode 111. On the other hand, the opposite robot arm 101b is positioned at the bottom of the slot 140.

Subsequently, the supply of current to the robot arm 101a positioned above the high voltage electrode 111 is stopped to drop the explosive material 160 attached to the electromagnet 102 in the direction of the high voltage electrode 111, and below the slot 140. The explosive material 160 is repeatedly taken out by supplying a current to the located robot.

Next, after rotating the robot arm 101 by 90 degrees by the operation of the drive motor 103, by closing the sliding door 150 to isolate the feeding unit 100 and the electrode unit 110, The robot arm 101, the rotor 104, and the explosion material 160 of the slot are prevented from being deformed by the shock wave.

In addition, the sliding door 150 is closed and at the same time the operation of the switch to supply the pulse power to the high voltage electrode 111 to electrically explode the explosion material 160 seated on the high voltage electrode 111, after the electrical explosion sliding door ( As the 150 is opened, the robot arm 101 rotates by 90 degrees again to repeatedly supply the explosive material 160.

At this time, the electric energy introduced into the electric explosion is increased to 100KJ from the conventional several KJ to maximize the amount of nano-powder generated in one electric explosion.

As described above, the process of supplying the explosive material-rotating the robot arm-closing the sliding door-electric explosion occurs continuously for several seconds, and through the repetition of this process, mass production of the nanopowder becomes possible.

On the other hand, the concentrator 20 is installed on one side of the explosion apparatus 10 to condense (separation of particles) colloidal liquid generated by the electrical explosion, the colloid that is ejected by the electrical explosion inside the lower chamber 120 A sampling tube 200 is mounted on the upper side of the lower chamber 120 to collect the liquid, and the collecting tube 200 serves to communicate the lower chamber 120 and the storage container 210 of the transparent material. do.

In addition, the colloidal liquid 211 temporarily stored in the storage container 210 is adjusted in its capacity to be introduced into the concentration unit 25 by the inlet control valve 220, the liquid container 230 of the concentration unit 25 The colloidal liquid introduced into is heated by the heating unit 240 installed on one side of the liquid container 230.

A condensation pipe 250 and a condenser 260 are installed at the upper portion of the liquid container 230 to liquefy the colloid evaporated by heating, and a condensation vessel 270 is connected to one side of the condensation pipe 250 to liquefy. The separated particle separation liquid 271.

The circulation device 30 is configured to reflow the particle separation liquid 271 into the lower chamber 120, and a circulation pipe 300 connecting the concentrated container 270 and the lower chamber 120 is installed to separate particles. The liquid 271 provides a route for movement, and the circulation motor 320 is mounted on the circulation pipe 300 to provide a power source for reflowing the particle separation liquid.

In addition, a shear flow rate control valve 310 is installed on the circulation pipe 300 located at one side of the concentration vessel 270 to adjust the flow rate of the particle separation liquid 271 discharged from the concentration vessel 270, the lower chamber ( The rear end flow control valve 330 is installed on the circulation pipe 300 located at one side of the 120 to adjust the flow rate of the particle separation liquid flowing into the lower chamber 120.

Looking at the operation of the concentrator and the circulation device as follows.

In the lower chamber 120, the colloidal liquid ejected by electro-exploding the explosive material 160 is collected by a collecting tube 200 installed in the upper portion of the lower chamber 120, and the collected colloidal liquid is stored in the storage container 210. Save it temporarily.

Thereafter, by using the inlet control valve 220 mounted on one side of the storage container 210 to adjust the proper flow rate of the colloid 211 liquid supplied from the storage container 210 to the liquid container 230, the liquid container ( The colloidal liquid 231 introduced into the 230 is heated by using the heating unit 240.

Here, the heating unit 240 may use a conventional microwave heater using a microwave, in addition to using a heating wire heater or a gas burner heater using a gas to supply electricity to the heating wire to generate heat. It is possible.

In addition, the selection of which heater to use for the heating unit 240 is determined in consideration of the volume of the colloidal liquid to be heated, installation and maintenance costs of each heater, thermal efficiency according to the heating environment.

Next, the colloid evaporated by the heating unit 240 is cooled and liquefied through the condenser 260, the liquefied particle separation liquid 271 is stored in the concentration vessel 270 along the condensation pipe 250.

At this time, the colloidal liquid collected by the collection pipe 200 is not re-introduced into the lower chamber 120, but after the heating-evaporation-cooling-liquefaction process to generate the particle separation liquid 271 and re-introduction This is to filter out particles and the like from the colloid.

Meanwhile, the particle separation liquid 271 stored in the concentration vessel 270 is reintroduced into the lower chamber 120 along the circulation pipe 300 connected to one side of the concentration vessel 270. At this time, by operating the inlet control valve 220 and the circulation motor 320 installed on the circulation pipe 300 to adjust the flow rate and speed of the particle separation liquid to an appropriate value.

As described above, the present invention can produce a large amount of nano-powder by repeatedly supplying the rod-shaped explosive material 160 to the electrode unit 110 by using the robot arm 101 and the rotor 104, a thickening apparatus It is possible to recycle the liquid separated from the particles by concentrating and reintroducing the colloidal liquid ejected during the electric explosion using the 20 and the circulator 30.

While the invention has been shown and described with respect to certain preferred embodiments thereof, the invention is not limited to these embodiments, and has been claimed by those of ordinary skill in the art to which the invention pertains. It includes all the various forms of embodiments that can be carried out without departing from the spirit.

1 is a start view of the nano-powder mass production system by electric explosion in liquid according to the present invention,

2 is an exploded view of the explosive device of FIG. 1;

3 is an operation of the feeding unit according to the present invention.

10: explosion device 20: concentration device

30: circulation device 100: feeding part

110: electrode portion 120: lower chamber

140: slot 150: sliding door

160: explosive material 200: collecting pipe

210: storage container 300: circulation pipe

Claims

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(d) storing the colloidal liquid ejected by the electric explosion in a storage container through a collecting tube mounted on an upper side of the lower chamber;

It is configured to include,

In the step (a), the explosive material loaded in the slot is mounted and dismounted by using an electromagnet-attached robot arm, and the robot arm is rotated by the operation of the driving motor while the explosive material is mounted and dislodged. Mass production method of nano-powder by liquid explosion in a liquid.

It is configured to include,

Step (e) is a step of storing the colloidal liquid introduced into the appropriate amount by the inlet control valve in a liquid container; Heating and evaporating the colloidal liquid stored in the liquid container with a heating unit; Cooling and liquefying the evaporated colloidal vapor with a condenser; Storing the liquid separated from the liquid due to the liquefaction in a concentration vessel;

Nano-powder mass production method by an electric explosion in a liquid, characterized in that comprises a.

Nano-powder mass production system by electric explosion in a liquid, characterized in that comprises a.

The rotor according to claim 5, wherein the feeding unit includes a driving motor and is installed on an upper portion of the lower chamber; A robot arm mounted on both sides of the rotor to mount and dismount the explosive material using an electromagnet;

The method of claim 5, wherein the electrode portion and the high-voltage electrode formed in the form of a stepped conical container; An electrode support disposed under the high voltage electrode to insulate and support the high voltage electrode;

The liquid container of claim 5, wherein the concentrating unit comprises: a liquid container for storing colloidal liquid controlled to be introduced by the inflow control valve; A heating unit installed at one side of the liquid container to heat the colloidal liquid; A condenser mounted on an upper portion of the liquid container to cool and liquefy colloidal vapor evaporated by the heating unit; A condensation vessel installed at a lower portion of the condenser to store the particle separation liquid liquefied by the condenser, and being connected to the circulation pipe;

The nanopowder mass production system according to claim 8, wherein the heating unit selects and uses one of a microwave heater, a heating wire heater, and a gas burner heater.