KR101106650B1 - Apparatus for forming a glomeration ceramic powder and glomeration ceramic powder manufactured by the apparatus - Google Patents

Abstract

The present invention relates to a spherical ceramic powder manufacturing apparatus for spheroidizing ceramic powder with a flame formed by using an oxygen burner, and a spherical ceramic powder produced using the same, the spherical ceramic powder manufacturing apparatus transfers ceramic powder to a screw conveyor. After that, the powder supply device for discharging the ceramic powder with a carrier gas at a constant pressure, and the ceramic powder discharged by the carrier gas from the powder supply device to the mixed gas supplied with oxygen and LPG mixed in advance and oxygen supplied alone And a burner for solidifying the ceramic powder by melting it with a flame formed by solidification in the air and collecting the ceramic powder spheroidized by the burner in a cyclone manner. In the present invention, the screw conveyor can be used in parallel with the vibration supply, the spherical ceramic powder manufacturing apparatus of the present invention uses a burner of a mixture of an internal mixed burner and an external mixed burner to generate a high temperature flame. .

Spherical ceramic, oxygen burner, screw spinning, heat treatment

Description

Apparatus for forming a glomeration ceramic powder and glomeration ceramic powder manufactured by the apparatus

The present invention relates to a spherical ceramic powder manufacturing apparatus and a spherical ceramic powder manufactured using the same, and more particularly, a spherical ceramic powder for producing a spherical ceramic powder having a high particle size and a high density with a flame formed by using an oxygen burner. It relates to a manufacturing apparatus and spherical ceramic powder produced using the same.

Ceramic materials are excellent in thermal conductivity and have good insulating properties. Therefore, ceramic materials are widely used in heat dissipation sheets or heat dissipation substrate fillers that release heat generated from electronic materials.

The ceramic inorganic material used as the thermally conductive filler of the heat dissipation sheet affects the thermal conductivity of the sheet according to its filling rate.

The thermally conductive sheet is composed of an organic matrix and spherical ceramic particles, and has a thermal conductivity of 1.0 W / m · K or more. Here, the spherical ceramic is generally filled with 30 to 80% by volume of the organic matrix. Since the thermal conductivity of the thermally conductive sheet is higher as the filling ratio of the spherical ceramic is improved, efforts are made to increase the filling ratio by preparing a spherical ceramic powder suitable for closest filling.

To date, spherical ceramic powders are manufactured using a thermal spraying method, and the particle size of the ceramic powder is limited to a maximum of 50 μm or less due to the limitation of the manufacturing method.

As an example of a conventional spherical ceramic manufacturing method, Korean Patent Laid-Open Publication No. 10-2002-7017459 (name of the invention: a method for producing a spherical oxide powder and a spherical powder manufacturing apparatus, a composite dielectric material, a substrate and a method for manufacturing a substrate) Can be presented. This uses a burner to produce spherical ceramic powder suitable for complexing with a resin material. Korean Patent Laid-Open Publication No. 10-2002-7017459 described above discloses a technique for producing spherical ceramic powder having a particle size of 1 to 10 μm and a sphericity of 0.9 or more, using LPG, hydrogen, acetylene, or the like as a combustion gas of a burner. And granular powder for controlling the particle size of the alumina powder to be supplied, and installing a heating means to prevent a sudden temperature drop after the heat treatment.

As another example of the conventional spherical ceramic manufacturing method, Korean Patent No. 10-2002-0070430 (name of the invention: a burner for manufacturing spherical molten fine powder) may be presented. This manufactures spherical molten fine powder using a thermal spraying method, and includes a technique using an internal mixed burner, using LPG as a combustion gas, and adjusting the length of the combustion flame to realize uniform spheroidization. Here, the internal mixed burner refers to a pre-mix type burner that mixes fuel gas and supply gas in advance and then ignites it.

And, as another example of the conventional spherical ceramic manufacturing method, Korean Patent No. 10-2002-0070429 (name of the invention: spherical melting fine powder manufacturing apparatus and its manufacturing method) may be presented. This is to produce a silica powder having an average particle size of 20㎛ or less by using an internal mixing burner and a device that enables continuous operation, using an internal mixing burner using LPG as combustion gas, and the first, The compressed air inlet of 2 is formed to enable continuous operation, and has a cooling air inlet so that the molten inorganic powder is instantaneously cooled.

However, according to the conventional spherical ceramic manufacturing method described above, spherical ceramics having a particle size of less than 50 µm can be obtained by using a conventional thermal spray method using LPG or C ₂ H ₂ as combustion gas, but LPG or C ₂ When H ₂ is used as the combustion gas, it is difficult to produce a powder of 50 μm or more because a sufficient high temperature flame cannot be obtained.

Therefore, the sphericity rate is not good for powders having a particle size of 50 µm or more, and the incidence of pores is high, making it difficult to manufacture dense spherical ceramics.

In addition, the type of burner is largely classified into an internal mixed burner and an external mixed burner. In the case of using an internal mixed burner, there is an advantage in that the combustion gas and the crude gas are mixed in advance and burned efficiently. The combustion efficiency may be lowered according to the phenomenon, and when the external mixed burner is used, there is an advantage of controlling the mixing ratio of the gas, but there is a problem in that carbon is generated due to incomplete combustion.

An object of the present invention is to provide an apparatus for producing spherical ceramic powder having a large particle size of 50 μm or more by using a thermal spray method using oxygen (O _{2 )} ) as a combustion gas.

Another object of the present invention is to provide a spherical ceramic powder production apparatus capable of preventing carbon generation while increasing combustion efficiency by using a burner having a structure in which an external mixed type and an internal mixed type are mixed.

Another object of the present invention is to produce a spherical ceramic powder using a spherical ceramic powder manufacturing apparatus.

The spherical ceramic powder production apparatus according to the present invention comprises: a powder supply apparatus for transferring ceramic powder to a screw conveyor and discharging the ceramic powder with a carrier gas at a constant pressure; The ceramic powder discharged by the carrier gas from the powder supply device is melted with a flame formed by a mixed gas supplied with oxygen and LPG mixed with oxygen and LPG supplied in advance, and then solidified in the air to spheroidize the ceramic powder. burner; And a collector for collecting the ceramic powder spheroidized by the burner in a cyclone manner.

The ceramic powder is Al ₂ O ₃ , SiO ₂ , TiO ₂ , ZrO ₂ , AlN, Si ₃ N ₄ , Ti ₃ N ₄ , Zr ₃ N ₄ , Al ₄ C ₃ , SiC, TiC, ZrC, AlB, Si ₃ B ₄ , Ti ₃ B ₄ , Zr ₃ B ₄ Any one can be used.

And, the powder supply device, a motor for providing a rotational driving force; A screw conveyor which is shaft-coupled with the motor to receive the rotation driving force and uniformly transfers and discharges ceramic powder supplied inside the cylinder through a hopper formed thereon in one direction by rotation of a screw formed in a shaft in a horizontal direction; And an ejector provided with ceramic powder discharged from the screw conveyor through a first hose, and loaded into the burner by loading the ceramic powder in a carrier gas at a constant pressure.

Here, the screw conveyor, the cylindrical cylinder; A hopper formed at one end of the cylinder; A shaft having a uniform diffraction angle formed successively in the longitudinal direction, installed in a hollow in the cylinder, and rotating to receive a rotational force from the motor; And a discharge pipe installed at a lower side opposite to the cylinder in which the hopper is installed.

In addition, the vibrating body is further installed in the discharge pipe, so that the ceramic may be configured to be transferred in an equal amount by vibration.

The ejector may include an inlet pipe into which the carrier gas is introduced; A nozzle pipe coupled to one end of the inlet pipe and injecting the carrier gas through a beak formed at an end thereof; A discharge pipe for discharging ceramic powder carried by the carrier gas injected from the nozzle pipe; And a T-type pipe, wherein the T-type pipe includes first and second openings communicating with the nozzle tube and the discharge pipe, and the ceramic powder discharged from the screw conveyor is introduced into the first and second pipes. Preferably, a third opening is formed in a direction crossing the direction in which the opening communicates with each other, and the nozzle tube extends to a position where the ceramic powder in the T-shaped pipe flows.

In addition, the burner is a heat-resistant furnace; A pilot burner for establishing an ignition temperature for oxygen combustion in the heat resistant furnace; And a burner assembly configured to spray the ceramic powder, oxygen and LPG mixed gas and oxygen gas, which are carried on the carrier gas, into the heat-resistant furnace and spheroidize the ceramic powder by the ignition flame.

Here, the burner assembly, the powder transfer pipe for transferring the carrier gas and the ceramic powder; A mixed transport tube inserted into an outer side of the powder transport tube; An oxygen transport pipe inserted into the outside of the mixed transport pipe; A second spraying unit having a plurality of second spraying holes and a third spraying unit having a plurality of third spraying holes are assembled in the center of the center of the first spraying unit having a plurality of first spraying holes and sequentially The first end of the powder transfer pipe is assembled in one spray unit, the first end of the mixed feed pipe is assembled in the second spray unit, and the first end of the oxygen transfer pipe is assembled in the third spray unit. ; A cooling unit configured at an outer side of the oxygen transfer pipe and having a structure for introducing, purifying and discharging cooling water; A mixed gas induction part installed at a second end of the mixed transport pipe to guide a mixed gas of oxygen and LPG to the mixed transport pipe; And an oxygen induction part installed at the second end of the oxygen transport pipe to guide oxygen to the oxygen transport pipe, wherein the ceramic powder carried in the carrier gas is the first material of the powder transport pipe and the first injection unit. 1 is injected into the injection port, the mixed gas of the oxygen and LPG is injected into the second injection port of the mixed gas induction unit, the mixed transfer pipe and the second injection unit, the oxygen is in the oxygen induction unit, the oxygen transfer pipe and the Preferably, the third injection unit is injected into the third injection port.

The second injection port of the second injection unit may further include a through hole communicating with an end portion of the oxygen transfer pipe.

The collector may collect the ceramic powder in a cyclone manner.

And, the flame is preferably formed to have a temperature of 2600 ℃ to 3000 ℃.

In addition, oxygen may be used as the carrier gas.

According to the present invention, there is an effect that a good spherical ceramic powder of 50 µm or more can be produced by applying a thermal spraying method using a high temperature flame formed by combustion of oxygen (O ₂ ).

In addition, according to the present invention, by using a burner having a structure in which an external mixed type and an internal mixed type are mixed, there is an effect of increasing the combustion efficiency of the spherical ceramic powder production apparatus and preventing carbon generation.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the following embodiments are provided to those skilled in the art to fully understand the present invention, and may be modified in various forms, and the scope of the present invention is limited to the embodiments described below. It doesn't happen. Like numbers refer to like elements in the figures.

An embodiment of the spherical ceramic powder manufacturing apparatus according to the present invention is for spheroidizing the ceramic powder by a high temperature heat treatment.

Initial ceramic powders that can be used for spheroidization in the present invention are Al ₂ O ₃ , SiO ₂ , TiO ₂ , ZrO ₂ , AlN, Si ₃ N ₄ , Ti ₃ N ₄ , Zr ₃ N ₄ , Al ₄ C ₃ , SiC , TiC, ZrC, AlB, Si ₃ B ₄ , Ti ₃ B ₄ , Zr ₃ B ₄ may be used, among which an oxide is preferably used, and Al ₂ O ₃ may be typically used.

The spherical ceramic powder manufacturing apparatus according to the present invention may be implemented as shown in FIG. 1, and each element shown in FIG. 1 may be configured in detail as shown in FIGS. 2 to 4.

Figure 1 shows a block diagram of a spherical ceramic powder manufacturing apparatus according to the present invention.

The spherical ceramic powder production apparatus of FIG. 1 includes a powder supply device 2, a burner 4, and a collector 6.

The powder supply device 2 includes a screw conveyor 10 having a hopper 12, a motor 14 (see FIG. 2), and an ejector 20 (see FIG. 3).

Initial ceramic powder is introduced into the hopper 12 into the screw conveyor 10, and the screw conveyor 10 and the ejector 20 are connected to each other by a hose P1, and the ejector 20 is connected through a flow meter FM1. The carrier gas is supplied. In this case, the carrier gas is preferably oxygen.

The burner 4 includes a burner assembly 30 (see FIG. 4), a heat resistant furnace 40, and a pilot burner 44, and a switch 42 for ignition of the pilot burner 44 may be further provided. .

The burner assembly 30 is a gas injector receiving oxygen and LPG mixed gas and oxygen through a powder conveying pipe 32 connected to an ejector 20 and a hose P2, and flowmeters FM2, FM3 and FM4. 34) and a cooler 36 mounted on an outer wall of the gas injector 34, into which coolant is introduced and discharged.

The collector 6 includes a primary collector 60, a secondary collector 62, and an air pump 64, and the primary collector 60 is collected by a cyclone and the secondary collector 62. The collection is made by the pumping of the air pump (64).

Detailed description of each part of the embodiment according to the present invention configured as described above will be described with reference to Figs.

First, the configuration of the screw conveyor 10 and the motor 14 may be described with reference to FIG. 2, in which part of the cylinder 102 is cut away to explain the internal structure of the screw conveyor 10. It is.

The screw conveyor 10 includes a cylinder 102 as a main frame, and ceramic powder is injected into the upper portion and discharges the ceramic powder into the lower portion. Correspondingly, in the cylinder 102, a hopper 110 is formed at an upper portion into which ceramic powder is injected, and a discharge tube 112 is formed at a lower portion from which ceramic powder is discharged. The hopper 110 and the discharge pipe 112 is preferably configured to be spaced apart from both ends of the cylinder (102). And, the hopper 110 may be designed to have an inlet (not shown) of a sufficient area so that the ceramic powder can be smoothly supplied, the height may be designed in the range of 1 meter to 1.5 meters, but is not limited thereto. It can be implemented in various shapes and sizes according to the intention of the designer.

On the other hand, the cylinder 102 has a circular plate 118 having a diameter larger than itself at both ends in the longitudinal direction, and a through hollow is formed therein. The inner hollow of the cylinder 102 is provided with a screw 116 continuously formed in the longitudinal direction of the shaft 114 and the shaft 114. Here, the radius of the screw 116 may have a size such that a constant gap is formed between the inner walls of the cylinder 102, and the gap between the screw 116 and the cylinder 102 may smoothly transfer the ceramic powder. The range may be limited according to the intention of the producer.

Both ends of the shaft 114 extend to both ends of the cylinder 102 and have support holes 104 and 106 having a hole in the center and equipped with a rotating member (not shown) capable of supporting rotation, such as a bearing, on the inner wall of the hole. Each support plate (104, 106) has a circular plate 120 of a size and shape corresponding to the circular plate 118 of the cylinder 102 in contact with it, the circular of the support plate (104, 106) The plate 120 is coupled to the circular plate 118 of the cylinder 102 by a fastening member such as bolt 122. In addition, although the circular plate 120 of the support plates 104 and 106 through which the shaft 114 penetrates is not specifically illustrated, a conventional packing structure for preventing leakage of ceramic powder transferred from the inside of the cylinder 102 is prevented. It can have

By the above-described structure, the shaft 114 in the cylinder 102 can be guaranteed to rotate in one direction (for example, arrow A).

On the other hand, one end of the shaft 114 of the screw conveyor 10 may extend toward the motor 14 to be connected to the rotation axis (not shown) of the motor 14 and the conventional shaft joint, Figure 2 flange for shaft joint 132 is illustrated.

The motor 14 and the screw conveyor 10 described above may be fixedly installed by a separate bracket 130 or a support.

As described above with reference to FIG. 2, the motor 14 and the screw conveyor 10 are installed, and the shaft 114 of the screw conveyor 10 is rotated by the rotation driving force provided from the motor 14, and the shaft 114 of the shaft 114 is rotated. The screw 116 is rotated by the rotation.

As described above with reference to FIG. 2, the motor 14 is mounted on the screw conveyor 10 so that the screw conveyor 10 is operated by the rotation of the motor 14, and the shaft 114 is operated as the screw conveyor 10 is operated. Is rotated, the screw 116 is rotated in conjunction with the rotation of the shaft (114).

At this time, the ceramic powder introduced into the screw conveyor 10 through the hopper 110 may be arbitrarily adjusted according to the speed of the screw 116, preferably 50 liters per hour when the ceramic powder is Al ₂ O ₃ The amount is preferably supplied, and the speed of the screw 116 is dependent on the rotational speed per minute of the motor 114.

The ceramic powder introduced into the cylinder 102 by the operation of the screw 116 is discharged to the discharge pipe 112, and the ceramic powder transferred to the discharge pipe 112 is transferred to the ejector 20 through the hose P1. do. Here, the diameter and the material of the hose P1 may be designed in consideration of the type and the transport amount of the ceramic powder. Preferably, the inner wall is surface-treated to prevent the ceramic powder from accumulating by static electricity or the like.

In addition, the discharge pipe 112 of the screw conveyor 10 may be further configured with a vibrating body 200, the screw conveyor 10 is further configured with a vibrating body 200 is shown in FIG.

The screw conveyor 10 having the vibrating body 20 receives the vibration generated from the vibrating body 20 to the discharge pipe 112, and by vibrating, the screw conveyor 10 discharges an equal amount of ceramic powder into the discharge pipe ( Discharge to 112 and transfer to the ejector 20 through the hose (P1).

In addition, the vibrator 20 is preferably configured to generate vibrations by operating a motor (not shown) built in by electric force, and the vibrator 20 may correspond to a configuration of a level that is commonly used. Therefore, even if the specific drawings are not shown, those skilled in the art may easily implement the drawings.

Hereinafter, the detailed structure of the ejector 20 which ejects the ceramic powder conveyed from the screw conveyor 10 is demonstrated with reference to FIG.

The ejector 20 is coupled to one end of the inlet pipe 204 and the inlet pipe 204 into which the carrier gas flows and is injected from the nozzle tube 206 and the nozzle tube 206 for injecting the carrier gas through the nozzle at the end. The T-type pipe 210 loads and ejects the ceramic powder on the carrier gas, and the discharge pipe 208 which guides the ejection of the ceramic powder loaded on the carrier gas in the T-type pipe 210.

Here, the T-shaped pipe 210 is coupled to the hose (P1) connected to the screw conveyor 10 to the inlet orthogonal to the nozzle tube 206 and the discharge pipe 208 are coupled to both inlet in communication.

Among the components constituting the ejector 20, the inlet pipe 204 is connected to the flow meter FM1 of FIG. 1 and is composed of a pipe receiving a constant pressure carrier gas, wherein the carrier gas may preferably use oxygen. Alternatively, air may be used.

And, the nozzle pipe 206 serves to guide the carrier gas transferred from the inlet pipe 204 into the T-shaped pipe 210, one end is piped with the end of the inlet pipe 204 and the other end is beak structure Has an end. Since the nozzle tube 206 has a narrower cross-sectional area of the inlet through which the carrier gas is discharged than the inlet through which the carrier gas is introduced, the carrier gas is injected into the beak structure end at high speed according to Bernoulli's theorem. The beak structure end of the inlet tube 204 may extend to the position where the outlet tube 208 is coupled within the T-pipe.

In addition, the discharge pipe 208 is piped to the inlet communicating with the inlet 204 is coupled to the inlet pipe 204 of the T-shaped pipe 210, the inner wall of one end piped with the T-shaped pipe 210 is the nozzle pipe 206 ) And the other end having a shape corresponding to the outer wall of the end of the nozzle tube 206 of the beak structure, the other end to guide the ceramic powder on the carrier gas is connected to the hose (P2) and the inner wall is in the direction that the ceramic powder is guided It has a shape that gradually increases in diameter.

By the ejector 20 as described above, the carrier gas is injected at a high pressure from the nozzle pipe 206 toward the discharge pipe 208 through the inlet pipe 204. As a result, the ceramic powder flowing into the T-shaped pipe 210 from the screw conveyor 10 is loaded on the carrier gas injected at a high pressure from the nozzle tube 206 and discharged toward the discharge tube 208.

Here, the supply amount of oxygen, which is the carrier gas supplied to the ejector 20, may be determined in consideration of the amount of LPG supplied from the burner 4 described later.

As described above, the powder supply device 2 is configured, so that the ceramic powder in the quantity can be supplied to the burner assembly 30 of the burner 4 by the carrier gas of positive pressure.

Burner assembly 30 of burner 4 may be configured as shown in Figure 4, Figure 4 (A) is a cross-sectional view, (B) is a carrier gas, ceramic powder, oxygen and LPG is injected to heat treatment It is the left side view which looked at the burner assembly 30 from the injection part 38 side made.

The burner assembly 30 is inserted into the powder transport pipe 32 and the powder transport pipe 32 for transporting the carrier gas and the ceramic powder, and guides the space between the outer wall of the powder transport pipe 32 and its inner wall. Oxygen that forms the induction pipe 356 into the mixed transport pipe 322 constituting the pipe 352 and the space between the outer wall of the mixed transport pipe 322 and its inner wall is inserted into the outside of the mixed transport pipe 322 Including a pipe 324, each of the powder transport pipe 32, the mixed transport pipe 322 and the oxygen transport pipe 324 has a different length and one end is aligned to the injection portion 38 side of each of the injection portion 38 Combined with the unit.

The injection part 38 has a ring shape inserted into an outer diameter of the first injection unit 380 and the first injection unit 380 having a plurality of injection holes 381 formed at the center and the periphery thereof, and having a plurality of injection holes 383. ) Has a ring shape inserted into the outer diameter of the second spray unit 382 and the second spray unit 382 formed by being dispersed on the front surface of the ring, and a plurality of injection holes 387 are formed by being dispersed on the front surface of the ring. And an injection unit 386.

Here, the powder transfer pipe 32 is fitted to the rear protrusion of the first spraying unit 380, the mixed transfer pipe 322 is fitted to the rear protrusion of the second spraying unit 382, and the oxygen transfer pipe 324. Is fitted to the rear projection of the third spraying unit.

In addition, the second injection unit 382 further includes a through hole 385 communicating between the induction pipe 356 of the oxygen transfer pipe 324 and the injection hole 383 of the second injection unit 382.

In addition, the mixed transport pipe 322 is shorter than the powder transport pipe 32 and the oxygen transport pipe 324 is shorter than the mixed transport pipe 322, and these are aligned to the rear of the injection portion 38 thereof to be opposed to them. The opposite end has a step.

The mixed gas induction part 340 and the oxygen induction part 342 are configured in an area where the step is formed, and the oxygen induction part 342 has an inlet 354 communicating with the induction pipe 356 orthogonal to the oxygen transport pipe 324. The third spray unit 386 of the () is coupled to the opposite end to which it is coupled and has a space spaced apart from the outer wall of the mixed feed pipe (322).

In addition, the mixed gas induction part 340 has an inlet 350 which communicates with the induction pipe 352 while being orthogonal to each other, and has one end inserted into a space spaced between the mixing transfer pipe 322 and the oxygen induction part 342 to provide an airtight therebetween. Ball bearing 344 is configured on the end side wall contacting the oxygen induction part 342 so as to ensure rotation, and the other end has a space spaced apart from the outer wall of the powder transfer pipe (32).

The space spaced apart from the powder transfer pipe 32 of the mixed gas induction part 340 is kept airtight by the packing part 346, and the packing part 346 has the powder transfer pipe 32 inserted into the center through hole. And coupled to the mixed gas induction part 340 by the bolt 348.

Meanwhile, a cooling unit 36 is formed between the oxygen induction unit 342 and the injection unit 38, and the cooling unit 36 has a structure in which cooling water is introduced and circulated, and discharged, and the cooling water forms an outer wall of the oxygen transfer pipe 324. It has a structure to cool.

By the above-described configuration, the carrier gas discharged from the ejector 20 and transported through the hose P2 and the ceramic powder contained therein are introduced into the powder transfer pipe 32 to form the first spray unit of the injection unit 38. 380 is injected to the injection port 381.

In addition, the inlet 350 of the mixed gas induction part 340 is mixed with oxygen and LPG supplied by the flow meters FM2 and FM3, and the mixed gas is introduced into the mixed gas pipe 322. Then, it is injected to the injection port 383 of the second injection unit 382.

In addition, oxygen in which the supply amount is adjusted by the flow meter FM4 flows into the inlet 354 of the oxygen induction part 342, and oxygen passes through the oxygen transfer pipe 324 to the injection hole 387 of the third injection unit 386. Sprayed). At this time, some oxygen transported through the oxygen transfer pipe 324 is injected through the injection port 383 of the second injection unit 382 through the through hole 385. As a result, the injection port 383 injects the mixed gas in which oxygen introduced through the oxygen transfer pipe 324 is added to the mixed gas of oxygen and LPG injected through the mixed transfer pipe 322.

The ceramic powder, oxygen and LPG mixed gas and oxygen injected from the injection assembly 30 of FIG. 4 are introduced into the heat-resistant furnace 40.

By the configuration of the embodiment according to the present invention described above, the process of spheroidizing the ceramic powder will be described.

The initial ceramic powder is introduced into the screw conveyor 10 through the hopper 110, and the initial ceramic powder (eg, alumina (Al ₂ O ₃ ) powder) injected into the screw conveyor 10 is illustrated in FIGS. 5A and FIG. Same as 5b. 5A and 5B are scanning electron microscope (SEM) images of ceramic powders having different magnifications, and have irregular shapes and particle sizes of less than 50 μm.

The above-mentioned ceramic powder is transferred by the rotation of the screw 116 of the screw conveyor 10, and the ceramic powder inside the screw conveyor 10 is transferred to the ejector 20 through the hose P1.

The ejector 20 is supplied with oxygen used as a carrier gas at a high pressure, and thus, the ceramic powder is loaded on the carrier gas injected at a high speed, so that the powder transfer pipe 32 of the burner assembly 30 is connected through a hose P2. Eject to.

The burner assembly 30 receives the ceramic powder contained in the carrier gas through the powder transfer tube 32, receives the mixed gas of oxygen and LPG through the mixed transfer tube 322, and receives oxygen through the oxygen transfer tube 324. . And, the burner assembly 30 is formed in the injection unit 38 to the ceramic powder, oxygen and oxygen and LPG mixed gas supplied to the powder transfer pipe 32, the mixed transfer pipe 322 and the oxygen transfer pipe 324 in the injection section 38 The injection holes 381, 383, 385, and 387 are injected into the heat-resistant furnace 40.

On the other hand, the pilot burner 44 is ignited by the operation of the switch 42, the pilot burner 44 is used to assist the combustion because the oxygen does not burn itself, it can be used to use LPG and air It is used to create a ignition temperature in which the oxygen can burn in the heat-resistant furnace (40).

Therefore, the pilot burner 44 is preferably ignited before the ceramic powder is injected into the heat-resistant furnace 40 so that the interior of the heat-resistant furnace 40 maintains above the temperature at which oxygen can burn. Here, the LPG supplied into the heat-resistant furnace 40 may be supplied with a supply amount of 7.5Nm 3 / h to 100Nm 3 / h, and oxygen (O ₂ ) may be controlled by 5 times the amount of LPG gas supplied. When the amount of heat in the heat-resistant furnace 40 of the burner 4 is 300,000 to 2,000,000 Kcal, a stable flame may be generated.

In addition, the burner 4 according to the present invention has a structure in which a mechanism using oxygen injected independently of a mechanism using a gas in which oxygen and LPG are mixed in advance, and the combustion efficiency is increased by this structure. Carbon production can be prevented.

And, the ceramic powder is supplied to the burner 4 in a constant amount and speed by a carrier gas having a constant pressure, the amount of ceramic powder supplied to the burner 4 is the amount of ceramic powder and screw (injected into the screw conveyor 10) It can be adjusted by adjusting the number of revolutions of 116, the ceramic powder can be set to supply a maximum of 50 liters per hour.

As described above, the ceramic powder injected into the heat-resistant furnace 40 of the burner 4 is melted by a flame formed by oxygen, and the molten powder is solidified while moving through the atmosphere in the heat-resistant furnace 40. It is made into a powder.

In the heat-resistant furnace 40, a flame that generates oxygen as a combustion gas is formed, and combustion of oxygen may form a higher temperature than that caused by combustion of LPG or C ₂ H ₂ gas. The flame temperature formed in the heat-resistant furnace 40 is preferably at least 2500 ° C, preferably at least 2600 ° C. And, the flame temperature is preferably set to 3000 ° C or less.

As described above, the powder spheroidized by melting and solidifying in the heat-resistant furnace 40 is moved to the collector 60, and the collector 60 performs collection in a cyclone manner. And the ceramic powder moved from the heat-resistant furnace 40 to the collector 60 may be collected by the collector 62, the collector 62 may collect the ceramic powder by the air pumping of the air pump (64).

Particles having a large particle size among the ceramic powders collected in the collector 60 may increase the sphericity by passing the burner 4 again by feedback and heat treatment twice, and the ceramic powder having a small particle size is also burner 4 again. Through a re-heat treatment process to pass through can be made of a spherical ceramic powder having a large particle size. That is, the embodiment according to the present invention can improve the size and sphericity of the spherical ceramic by producing a ceramic powder in a continuous circulation system.

6 to 8 are SEM photographs of the cross-sections of the spherical ceramics, the single powder ceramic powder, and the ceramic powder prepared according to the embodiment of the present invention, and FIGS. 6 to 8 show the LPG input amount of 15 Nm 3 / hr. The amount of oxygen injected was five times that of LPG.

According to the present invention as shown in Figures 6 and 8 it is possible to produce a spherical ceramic powder having a variety of particle size of 1 ~ 150㎛, in particular, it is possible to have a stable spherical shape with a high density even in particles of 50㎛ or more.

As mentioned above, although preferred embodiment of this invention was described in detail, this invention is not limited to the said embodiment, A various deformation | transformation by a person of ordinary skill in the art within the scope of the technical idea of this invention is carried out. This is possible.

1 is a block diagram of a spherical ceramic powder production apparatus according to the present invention.

FIG. 2 is a partial cutaway side view for explaining a coupling state of the motor 14 and the screw conveyor 10 of FIG. 1.

3 is a cross-sectional view for describing the ejector 20 of FIG. 1.

4 is a cross-sectional view of the burner assembly 30.

5A and 5B are SEM photographs of ceramic powders before heat treatment.

6 to 8 are SEM images of the ceramic powders, the individual ceramic powders, and the cross-sections of the ceramic powders produced by the spherical ceramic powder production apparatus according to the present invention.

FIG. 9 is a partial cutaway side view for explaining another embodiment in which the vibrating body 200 is mounted on the screw conveyor 10 of FIG. 1.

Claims (13)

A powder feeder for transferring the ceramic powder to a screw conveyor and discharging the ceramic powder to a carrier gas at a constant pressure; The ceramic powder discharged by the carrier gas from the powder supply device is melted with a flame formed by a mixed gas supplied with oxygen and LPG mixed in advance and supplied with oxygen alone, and then solidified in the air to spheroidize the ceramic powder. burner; And It includes a collector for collecting the ceramic powder spheroidized in the burner by a cyclone method, Receiving an ceramic powder discharged from the screw conveyor and loading the ceramic powder into a carrier gas at a constant pressure to discharge to the burner, The ejector, An inlet pipe through which the carrier gas is introduced; A nozzle tube coupled to one end of the inlet pipe and injecting the carrier gas through a beak formed at an end thereof; A discharge pipe for discharging ceramic powder carried by the carrier gas injected from the nozzle pipe; And Includes T-shaped pipes, The T-shaped pipe is intersected with a direction in which the first and second openings communicate with each other while the first and second openings communicating with the nozzle tube and the discharge pipe are coupled with the ceramic powder discharged from the screw conveyor. The third opening formed in the direction is formed, The nozzle tube extends to the position where the ceramic powder in the T-shaped pipe is introduced, The nozzle tube has a smaller cross-sectional area of the outlet for discharging the carrier gas than the cross-sectional area of the inlet through which the carrier gas is introduced from the inlet pipe, The discharge pipe has a shape that gradually increases in diameter in the direction in which the ceramic powder is guided, The burner includes a burner assembly which injects the ceramic powder, oxygen and LPG mixed gas and oxygen gas discharged on the carrier gas into the heat-resistant furnace and spheroidizes the ceramic powder by the ignition flame, The burner assembly, A powder transfer pipe for transferring the carrier gas and the ceramic powder; A mixed transport tube inserted into an outer side of the powder transport tube; An oxygen transport pipe inserted into the outside of the mixed transport pipe; An injection unit for injecting the ceramic powder, the mixed gas of oxygen and LPG, and the oxygen gas into a heat resistant furnace; A cooling unit configured at an outer side of the oxygen transfer pipe and having a structure for introducing, purifying and discharging cooling water; A mixed gas induction part installed at a second end of the mixed transport pipe to guide a mixed gas of oxygen and LPG to the mixed transport pipe; And It is installed on the second end of the oxygen transfer pipe and includes an oxygen induction unit for inducing oxygen to the oxygen transfer pipe, The injection unit, A first spraying unit located in the central portion having a plurality of first spraying spheres; A second injection unit having a plurality of second injection ports on the outer side of the first injection unit; And A third spraying unit having a plurality of third spraying spheres on the outside of the second spraying unit; The second spraying unit and the third spraying unit are sequentially assembled to the outer side of the first spraying unit, and the first spray unit is assembled to the first spraying unit, and the second spraying unit is assembled. A first end of the mixed transfer pipe is assembled into the first injection unit, and a first end of the oxygen transfer pipe is assembled into the third spraying unit. The powder conveying tube, the mixed conveying tube and the oxygen conveying tube have a different length and one end is aligned on the injection side, The length of the mixed feed pipe is shorter than the length of the powder feed pipe, the length of the oxygen feed pipe is shorter than the length of the mixed feed pipe, The mixed gas induction part is provided in an area where a step is formed along the length of the powder conveying pipe and the mixed conveying pipe, The oxygen induction part is provided in a region where a step is formed according to the length of the mixed transport pipe and the oxygen transport pipe, The ceramic powder carried in the carrier gas is injected into the powder injection pipe and the first injection port of the first injection unit, The mixed gas of the oxygen and LPG is injected into the second injection port of the mixed gas induction unit, the mixed feed pipe and the second injection unit, Spherical ceramic powder manufacturing apparatus, characterized in that the oxygen is injected into the third injection port of the oxygen induction portion, the oxygen transfer pipe and the third injection unit. The method of claim 1, wherein the ceramic powder is Al ₂ O ₃ , SiO ₂ , TiO ₂ , ZrO ₂ , AlN, Si ₃ N ₄ , Ti ₃ N ₄ , Zr ₃ N ₄ , Al ₄ C ₃ , SiC, TiC, ZrC, AlB, Si ₃ B ₄ , Ti ₃ B ₄ , Zr ₃ B ₄ Spherical ceramic powder manufacturing apparatus which is any one of. The method of claim 1, wherein the powder supply device, A motor providing a rotational driving force; A screw conveyor which is shaft-coupled with the motor to receive the rotation driving force and uniformly transfers and discharges ceramic powder supplied inside the cylinder through a hopper formed thereon in one direction by rotation of a screw formed in a shaft in a horizontal direction; And A spherical ceramic powder manufacturing apparatus comprising: an ejector provided with a ceramic powder discharged from the screw conveyor through a first hose, and loaded into the burner by loading the ceramic powder in a carrier gas at a constant pressure. The method of claim 3, wherein the screw conveyor, Cylindrical cylinder; A hopper formed at one end of the cylinder; A shaft having a uniform diffraction angle formed successively in the longitudinal direction, installed in a hollow in the cylinder, and rotating to receive a rotational force from the motor; And Spherical ceramic powder manufacturing apparatus comprising a; discharge pipe is installed on the lower side opposite the cylinder on which the hopper is installed. 5. The method of claim 4, Spherical ceramic powder production apparatus further provided with a vibrating body in the discharge pipe. delete The method of claim 1, wherein the burner, Heat resistant; And Spherical ceramic powder manufacturing apparatus comprising a pilot burner for setting the ignition temperature for oxygen combustion in the heat-resistant furnace. delete The method of claim 1, A spherical ceramic powder manufacturing apparatus of the second injection unit is further formed with a through hole communicating with the end of the oxygen transfer pipe. The method of claim 1, The collector is a spherical ceramic powder manufacturing apparatus for collecting the ceramic powder in a cyclone method. The method of claim 1, The flame is a spherical ceramic powder manufacturing apparatus is formed to have a temperature of 2600 ℃ to 3000 ℃. The method of claim 1, A spherical ceramic powder production apparatus in which oxygen is used as the carrier gas. The average particle size produced using the spherical ceramic powder production apparatus according to any one of claims 1 to 5, 7, and 9 to 12, having an average particle size of 1 to 150 µm and a sphericity of 0.9 or more. Spherical ceramic powder.

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