JP5887174B2 - Spheroidized particle manufacturing apparatus and spheroidized particle manufacturing method - Google Patents

Description

  The present invention relates to a spheroidized particle manufacturing apparatus and a spheroidized particle manufacturing method for manufacturing spheroidized particles.

Conventionally, various methods are known as methods for producing spheroidized particles of inorganic oxides, but the flame method is widely used industrially from the viewpoint of productivity and economy.
In the flame method, raw material powder is introduced into a flame formed by jetting fuel gas and combustion-supporting gas (supporting gas) from a burner, and the raw material powder is melted or semi-melted in a high-temperature atmosphere of the flame. In this method, spherical particles are obtained by spheroidizing the powder surface by surface tension (see, for example, Patent Documents 1 to 3).

  FIG. 7 is an enlarged cross-sectional view of the tip of the spheroidized particle manufacturing burner disclosed in Patent Document 3, and FIG. 8 is a plan view of the tip of the spheroidized particle manufacturing burner shown in FIG.

Here, with reference to FIG.7 and FIG.8, the structure of the conventional burner 100 for spherical particle manufacture is demonstrated.
A conventional burner 100 for producing spherical particles is a fuel composed of a raw material powder supply path 101 for supplying a raw material powder conveyed to a carrier gas and a plurality of supply paths arranged on the outer circumference of the raw material powder supply path 101. A gas supply path 102, a swirl oxygen supply path 103 composed of a plurality of supply paths disposed on the outer circumference of the fuel gas supply path 102, and a plurality of swirl oxygen supply paths disposed on the outer circumference of the swirl oxygen supply path 103 A straight oxygen supply passage 104, a cooling water passage 105a, 105b disposed on the outer circumference of the straight oxygen supply passage 104, and a combustion chamber 106 having a diameter expanded toward the tip side.

At the front end of the raw material powder supply path 101, a raw material powder jet 107 including a plurality of jets formed at the bottom 108 of the combustion chamber 106 is provided. Further, a fuel gas outlet 109 is provided at the tip of each supply path of the fuel gas supply path 102.
At the tip of each supply path of the swirl oxygen supply path 103, a swirl oxygen jet port 110 is provided. Further, a straight oxygen outlet 111 is provided at the tip of each supply path of the straight oxygen supply path 104.

FIG. 9 is a diagram showing a schematic configuration of a conventional spheroidized particle manufacturing apparatus disclosed in Patent Document 3. As shown in FIG.
Here, a conventional spheroidized particle manufacturing apparatus 120 will be described with reference to FIG.
A conventional spheroidized particle production apparatus 120 includes a raw material feeder 121, a carrier gas supply path 123, a burner 124, an oxygen supply facility 126, an LPG supply facility 127, a spheronization furnace 128, an air supply path 131, It has a cyclone 132 and a bag filter 133. The tip of the burner 124 that forms a flame is accommodated in the spheroidizing furnace 128. That is, a flame is formed in the spheroidizing furnace 128.

  In the conventional spheroidized particle manufacturing apparatus 120 configured as described above, the raw material powder is cut out from the raw material feeder 121, and the raw material powder is transferred to the burner 124 along with the carrier gas supplied from the carrier gas supply path 123. The

The burner 124 is supplied with oxygen from the oxygen supply facility 126 and is also supplied with combustion gas from the LPG supply facility 127, and the raw material powder passes through the flame formed in the spheroidizing furnace 128. Thus, spheroidized particles are generated.
Thereafter, the spheroidized particles are temperature-diluted by the air introduced into the bottom of the spheroidizing furnace 128 via the air supply path 131 and collected by the cyclone 132 and the bag filter 133 arranged in the subsequent stage.
Further, as the fuel gas, a gas mainly composed of methane or propane is used.

JP 58-145613 A Japanese Patent No. 3331491 Japanese Patent No. 3322228

  By the way, among the flames formed by the combustion reaction of fuel gas mainly composed of methane and propane, the flame method in which the raw material powder is melted in a high-temperature atmosphere is not used in the process of spheroidizing the raw material powder in the flame. There is a problem that fuel-derived carbon adheres to or is mixed into the spheroidized particles because fuel is generated.

  For example, when silica particles are mixed as spheroidized particles in a semiconductor chip sealing resin, and carbon is attached to or mixed in the silica particles, the carbon is conductive, so the wiring formed on the semiconductor chip Short circuit will occur between them.

Further, for example, when spheroidized particles with carbon adhering or mixed therein are used for a sealing material such as an LED, carbon is not desirable because it becomes an optical foreign matter as a black foreign matter.
For the above reasons, it is not preferable that carbon adheres to and is mixed into the spheroidized particles.

  As a means for preventing the carbon contained in the unburned fuel gas from adhering to or mixing into the spheroidized particles, the present inventors formed a burner flame outside the spheroidizing furnace, and the high temperature generated by the flame. Combustion gas (gas containing almost no unburned fuel gas) is introduced into the spheronization furnace, the raw material powder dispersed from the upper end side of the spheronization furnace is supplied, and the raw material powder is melted by the combustion gas. It came to the idea of producing spheroidized particles.

  FIG. 10 is a diagram showing a schematic configuration of a spheroidizing particle production apparatus used for preliminary examination by the present inventors, and FIG. 11 is a sectional view of the spheroidizing furnace, combustion chamber, and burner shown in FIG. . 10 and 11, the Y direction indicates the extending direction (vertical direction) of the spheroidizing furnace 147, and the X direction indicates a surface direction orthogonal to the Y direction.

Therefore, the present inventors made a spheroidized particle production apparatus 140 shown in FIG. 10 and conducted a preliminary study for confirming whether the above idea is correct.
Here, with reference to FIG.10 and FIG.11, the structure of the spheroidized particle manufacturing apparatus 140 which the present inventors used for prior examination is demonstrated.

  The spheroidized particle production apparatus 140 includes a carrier gas supply source 141, a combustion-supporting gas supply source 142, a fuel gas supply source 143, a raw material feeder 145, a spheroidizing furnace 147 extending in the vertical direction, and raw material powder. Body supply path 148, a plurality of raw material dispersion holes 149, a combustion chamber 151, a pair of burners 152-1 and 152-2, a plurality of combustion gas introduction holes 153, a blown gas introduction part 155, and spheroidized particles Deriving unit 156, blower blower 158, air inlet 162, spheroidized particle transport line 163, spheroidized particle collecting device 165 comprising cyclone 171 and bag filter 172, cooling gas introducing unit 168, cooling gas And an adjustment unit 169.

  The combustion chamber 151 is provided outside the side wall 147C of the spheronization furnace 147 located between the upper end 147A and the bottom part 147B of the spheronization furnace 147. The combustion chamber 151 exposes the entire outer surface 147a of the side wall 147C of the spheronization furnace 147 located between the upper end 147A and the bottom 147B of the spheronization furnace 147.

  The burners 152-1 and 152-2 are provided in the combustion chamber 151 such that the tips forming the flames 167-1 and 167-2 are exposed in the combustion chamber 151. The burners 152-1 and 152-2 eject the fuel gas (LPG) supplied from the fuel gas supply source 143 and the oxygen or oxygen-enriched air supplied from the combustion-supporting gas supply source 142 from the tip. Flames 167-1 and 167-2 are formed in the combustion chamber 151. The flames 167-1 and 167-2 are accommodated in the combustion chamber 21 located outside the spheroidizing furnace 147.

  The plurality of combustion gas introduction holes 153 pass through the side wall 147C of the spheroidizing furnace 147, and are arranged in the circumferential direction of the spheroidizing furnace 147 and the extending direction (Y direction) of the spheroidizing furnace 147. The plurality of combustion gas introduction holes 153 are exposed to the combustion chamber 151.

  A raw material in which the present inventors introduced a combustion gas containing almost no unburned fuel gas into the spheroidizing furnace 147 using the spheroidizing particle production apparatus 140 and dispersed from the upper end 147A side of the spheroidizing furnace 147. When the spheroidized particles are produced by melting the powder, the amount of carbon adhering to or mixed in the spheroidized particles can be reduced as compared with the case where the conventional spheroidized particle production apparatus 120 shown in FIG. 9 is used. It could be confirmed.

However, when using the spheroidized particle production apparatus 140 and particles having a large particle size (for example, particles exceeding 10 μm) are mixed in the raw material powder, particles of 10 μm or less are spheroidized, but particles of 10 μm or more are A new problem has been discovered that spheroidized particles having a stable shape cannot be obtained, such as not being spheroidized.

  This is because combustion gas having a relatively high temperature is supplied to the upper side of the spheroidizing furnace 147 extending in the vertical direction, and from the combustion gas supplied to the upper part of the spheroidizing furnace 147 on the lower side of the spheroidizing furnace 147. It is presumed that the combustion gas having a low temperature was supplied, a temperature gradient was formed in the spheroidizing furnace 147, and temperature variation occurred in the vertical direction in the spheroidizing furnace 147.

  Therefore, the present invention can suppress the adhesion or mixing of carbon to the spheroidized particles and can produce spheroidized particles having a stable shape even when a high melting point raw material powder is used. And it aims at providing the manufacturing method of spherical particles.

In order to solve the above-mentioned problem, according to the invention according to claim 1, the raw material powder is melted, the surface of the powder is spheroidized to generate spheroidized particles, and the spheroidization extending in the vertical direction A furnace, a plurality of raw material dispersion holes provided at an upper end of the spheronization furnace, and for dispersing the raw material powder supplied to the spheronization furnace in the spheronization furnace, an upper end of the spheronization furnace, and the spheroid provided on the outside of the side wall of the spherical furnace located between the bottom of the furnace, the outer surface of the side wall of the spherical furnace formed part of the inner wall, and with respect to the extending direction of the spherical furnace plurality and arranged combustion chamber are provided on each of the plurality of the combustion chamber, before Symbol a burner to form a flame in the combustion chamber, the spheroidized so as to communicate with said spherical furnace and said combustion chamber Te It penetrates the side wall of the furnace, the combustion chamber of the combustion gas produced by the flame A plurality of combustion gas introducing hole leading to serial spheroidizing furnace, spherical particles production apparatus characterized by having a provided.

Further, according to the invention of claim 2, spherical particles production apparatus according to claim 1, characterized in that it has a control unit for controlling the burner provided in the plurality of combustion chambers each independently Is provided.

Further, the invention according to claim 3, wherein the control unit, according to claim 2, characterized in that adjusting the amount of the combustion gas flame of the burner provided in the plurality of combustion chambers to produce The described spheroidized particle production apparatus is provided.

Further, the invention according to claim 4, a fuel supply for supplying fuel to the burner provided in the plurality of combustion chambers, combustion-supporting to the burner provided in the plurality of combustion chamber A combustion-supporting gas supply source that supplies gas; and a plurality of temperature detectors that are arranged in the spheronization furnace and detect the temperature in the vertical direction in the spheronization furnace, and the control unit includes: based on the temperature in which a plurality of temperature detectors for detecting the amount of the fuel supplied to the burner provided in the plurality of combustion chambers, and claims, characterized in that adjusting the amount of the combustion supporting gas Item 2 or 3 provides a spheroidized particle production apparatus.

  Moreover, according to the invention which concerns on Claim 5, these combustion gas introduction holes are arrange | positioned in the position spaced apart from the said flame, The spherical shape of any one of Claims 1 thru | or 4 characterized by the above-mentioned. An apparatus for producing particle is provided.

Moreover, according to the invention which concerns on Claim 6 , these combustion gas introduction holes are arrange | positioned in the circumferential direction of the said spheroidizing furnace, and the extending direction of this spheroidizing furnace, The 1st thru | or 5 characterized by the above-mentioned. Among them, the spheroidized particle production apparatus according to any one of the above is provided.

According to the invention of claim 7 , the plurality of combustion chambers are provided with the plurality of burners, respectively , and the plurality of burners are arranged opposite to each other with the central axis of the spheroidizing furnace interposed therebetween. The spheroidized particle manufacturing apparatus according to any one of claims 1 to 6 is provided.

Moreover, according to the invention which concerns on Claim 8 , the extending direction of these combustion gas introduction holes is the same direction as the normal line direction of the said spheronization furnace, Among the Claims 1 thru | or 7 characterized by the above-mentioned. The spheroidized particle manufacturing apparatus according to any one of the above is provided.

Further, the invention according to claim 9, the extending direction of said plurality of combustion gas introducing hole of the claims 1 to 7, characterized in that the same direction as the tangential direction of the spheroidizing furnace, An apparatus for producing spheroidized particles according to any one of the above items is provided.

According to the invention of claim 10 , the plurality of combustion gas introduction holes have a structure capable of supplying the combustion gas obliquely downward, according to any one of claims 1 to 7. The apparatus for producing spheroidized particles according to the item is provided.

Moreover, according to the invention which concerns on Claim 11 , the side wall of the said spheronization furnace is comprised with the refractory material, The spheroidized particle manufacture in any one of Claims 1 thru | or 10 characterized by the above-mentioned. An apparatus is provided.

Further, the invention according to claim 12, provided in a portion located at the bottom of the front Symbol sphere Joka furnace, a blowing gas inlet for introducing the blowing gas into the spherical reduction furnace, before Symbol ball Joka The part positioned at the bottom of the furnace is opposed to the blowing gas introduction part, and the spheroidized particle derivation part for deriving the spheroidized particles from the spheronization furnace, and the spheroidized particle derivation part The spheroidized particle producing apparatus according to any one of claims 1 to 11 , further comprising a spheroidized particle collecting apparatus that collects the spheroidized particles.

According to the invention of claim 13 , the spheroidized particle collecting device is connected to the spheroidized particle derivation unit, and collects particles having the first particle diameter among the spheroidized particles. A cyclone that is disposed downstream of the cyclone, and a bag filter that collects particles having a second particle size smaller than the first particle size among the spheroidized particles, the cyclone and the bug A spheroidized particle manufacturing apparatus according to claim 12 , further comprising a spheroidized particle transport line that connects a filter and transports a part of the spheroidized particles to the bag filter.

According to the invention of claim 14 , provided in the spheroidized particle transport line is a cooling gas inlet for introducing a cooling gas, and is provided in the cooling gas inlet, and is introduced into the spheroidized particle transport line. A spheroidized particle manufacturing apparatus according to claim 13 , further comprising a cooling gas adjusting unit that adjusts an introduction amount of the cooling gas.

Moreover, according to the invention which concerns on Claim 15 , It is the spheroidized particle manufacturing method using the spheroidized particle manufacturing apparatus of any one of Claims 1 thru | or 14 ,
The combustion gases produced in said plurality of combustion chamber is introduced into said spheroidizing furnace, the combustion gases, spherical particles, characterized in that to produce the raw material powder is melted spherical particles A manufacturing method is provided.

Moreover, according to the invention which concerns on Claim 16 , the said combustion gas is produced | generated by making a fuel and combustion support gas burn completely with the said burner, The spheroidized particle manufacturing method of Claim 15 characterized by the above-mentioned. Is provided.

Further, the invention according to claim 17, so that the temperature distribution suitable to melt the raw material powder is formed in the spheroidizing furnace, the burner provided in the plurality of combustion chamber 17. The method for producing spheroidized particles according to claim 16, wherein the amount of the fuel supplied to the fuel cell and the amount of the combustion-supporting gas are independently controlled.

Further, the invention according to claim 18, so that the temperature of the vertical direction of the spheroidizing furnace is made uniform, the amount of the fuel supplied to the burner provided in the plurality of combustion chambers and said The method for producing spheroidized particles according to claim 16 , wherein the amount of the combustion-supporting gas is independently controlled.

According to the onset bright, on the outside of the side wall of the spherical furnace located between the bottom of the top and spheroidizing furnace spheroidizing furnace, provided so as to expose the outer surface of the side wall of the spheroidizing furnace, and spherical A plurality of combustion chambers arranged with respect to the extending direction (vertical direction) of the combustor, a burner provided in each of the plurality of combustion chambers and forming a flame in the combustion chamber, and a spheroidizing furnace in which the combustion chamber is exposed A plurality of combustion gas introduction holes that penetrate the side wall and guide the combustion gas in the combustion chamber generated by the flame into the spheroidizing furnace, so that the burner is provided in the combustion chamber provided outside the spheroidizing furnace. It is possible to sufficiently burn the fuel gas and generate a combustion gas containing almost no unburned fuel gas.

  As a result, the raw material powder dispersed in the spheronization furnace is melted by the combustion gas containing almost no unburned fuel gas introduced into the spheronization furnace through a plurality of combustion gas introduction holes to form a sphere. Therefore, the amount of carbon adhering to or mixed in the spheroidized particles can be reduced as compared with the conventional case.

A plurality of combustion chambers provided to expose the outer surface of the side wall of the spheronization furnace, and disposed in a plurality of combustion chambers in the extending direction (vertical direction) of the spheronization furnace; and By having a burner that forms a flame in the combustion chamber, it becomes possible to reduce temperature variations in the spheroidizing furnace in the vertical direction.
This makes it possible to increase the time during which the raw material powder stays in the high-temperature combustion gas, so that spheroidized particles having a stable shape can be generated even when a high-melting-point raw material powder is used.

It is a schematic diagram which shows schematic structure of the spheroidized particle manufacturing apparatus which concerns on embodiment of this invention. It is sectional drawing of the X-ray direction of the spheronization furnace shown in FIG. 1, a combustion chamber, and the burner provided in this combustion chamber. It is sectional drawing of the spheroidizing furnace shown in FIG. 2, a combustion chamber, and the AA line direction of the burner provided in this combustion chamber. It is sectional drawing for demonstrating the other example of a combustion gas introduction hole. It is sectional drawing for demonstrating the modification of the structure shown in FIG. It is a figure which shows the temperature distribution of the perpendicular direction in the spheroidizing furnace of Example 1 and Reference Example 1. It is sectional drawing to which the front-end | tip part of the spheroidized particle manufacturing burner disclosed by patent document 3 was expanded. It is a top view of the front-end | tip of the burner for spheroidized particle manufacture shown in FIG. It is a figure which shows schematic structure of the conventional spheroidized particle manufacturing apparatus disclosed by patent document 3. FIG. It is a figure which shows schematic structure of the spheroidized particle manufacturing apparatus which the present inventors used for prior examination. It is sectional drawing of the spheronization furnace shown in FIG. 10, a combustion chamber, and a burner.

  Embodiments to which the present invention is applied will be described below in detail with reference to the drawings. The drawings used in the following description are for explaining the configuration of the embodiment of the present invention, and the size, thickness, dimension, etc. of each part shown in the figure are the dimensional relationship of an actual spheroidized particle manufacturing apparatus. May be different.

(Embodiment)
FIG. 1 is a schematic diagram showing a schematic configuration of a spheroidized particle manufacturing apparatus according to an embodiment of the present invention. In FIG. 1, the Y direction indicates the extending direction (vertical direction) of the spheroidizing furnace 18, and the X direction indicates a surface direction orthogonal to the Y direction.

  Referring to FIG. 1, the spheroidized particle manufacturing apparatus 10 of the present embodiment includes a carrier gas supply source 11, a carrier gas supply line 11 </ b> A, valves 12, 14 and 16, and a combustion-supporting gas supply source 13. The combustion-supporting gas supply line 13A, the fuel gas supply source 15 (fuel supply source), the fuel gas supply line 15A, the raw material feeder 17, the spheroidizing furnace 18, the raw material powder supply path 19, and a plurality of Raw material dispersion hole 20, combustion chambers 21 to 25, burners 31 to 40, combustion gas introduction holes 45 to 49, and combustion support gas flow rate adjustment valves 51 to 60 (for adjusting the flow rate of combustion support gas) Valve), fuel gas flow rate adjustment valves 61-70 (valves for adjusting the flow rate of fuel gas), temperature detectors 75-80, control unit 82, blowing gas introduction unit 84, and spheroidized particle derivation. Section 85, blower blower 87, and cooling gas introduction With a 88, a spheroidized particle transport line 89, a spheroidized particle collection device 91, the.

The carrier gas supply source 11 is connected to a carrier gas supply line 11A. The carrier gas supply source 11 is connected to the raw material feeder 17 through a carrier gas supply line 11 </ b> A in a state where the carrier gas can be supplied to the raw material feeder 17. For example, oxygen or oxygen-enriched air can be used as the carrier gas.
The valve 12 is provided in the carrier gas supply line 11A. By opening the valve 12, the carrier gas is supplied to the raw material feeder 17.

The combustion-supporting gas supply source 13 is connected to the combustion-supporting gas supply line 13A. The combustion-supporting gas supply source 13 supplies combustion-supporting gas to the burners 31 to 40 via a branch line branched from the combustion-supporting gas supply line 13A. As the combustion-supporting gas, for example, oxygen or oxygen-enriched air can be used.
The valve 14 is provided in the combustion-supporting gas supply line 13A. By opening the valve 14, the combustion-supporting gas is supplied from the combustion-supporting gas supply line 13A to the branch line.

The fuel gas supply source 15 is connected to a fuel gas supply line 15A. The fuel gas supply source 15 supplies fuel gas to the burners 31 to 40 through a branch line branched from the fuel gas supply line 15A. As the fuel gas, for example, LPG (Liquid Petroleum Gas) mainly containing butane (CH ₃ —CH ₂ —CH ₂ —CH ₃ ), propane (C ₃ H ₈ ), or the like can be used.
The valve 16 is provided in the fuel gas supply line 15A. By opening the valve 16, the fuel gas is supplied from the fuel gas supply line 15A to the branch line.
In the present embodiment, the case where fuel gas is used as fuel will be described as an example. However, liquid fuel may be used instead of fuel gas.

The raw material feeder 17 is for supplying raw material powder. The raw material powder supplied from the raw material feeder 17 is transported to the upper end of the spheroidizing furnace 18 through the raw material powder supply path 19 by the carrier gas supplied from the carrier gas supply source 11.
Examples of the raw material powder include silica (melting point is 1722 ° C.), alumina (melting point is 2053 ° C.), zirconia (melting point is 2680 ° C.), and the like.

  2 is a cross-sectional view in the X-ray direction of the spheroidizing furnace, combustion chamber, and burner provided in the combustion chamber shown in FIG. 1, and FIG. 3 is a spheroidizing furnace, combustion chamber, and It is sectional drawing of the AA line direction of the burner provided in this combustion chamber.

1 to 3, the spheroidizing furnace 18 is a vertical furnace extending in the Y direction (vertical direction). The spheroidizing furnace 18 can be, for example, cylindrical. In the present embodiment, the following description will be given by taking as an example the case where the spheroidizing furnace 18 has a cylindrical shape.
The spheronization furnace 18 is spheronized by melting the raw material powder supplied from the upper end 18A of the spheronization furnace 18 by the combustion gas generated in the combustion chambers 21 to 25 and introduced into the spheronization furnace 18. Generate particles.

Of the side wall 18C of the spheroidizing furnace 18, at least a portion where the combustion chambers 21 to 25 are exposed may be formed of a refractory material (for example, brick or amorphous castable).
Thereby, it can suppress that the side wall 18C of the spheronization furnace 18 is damaged by the flame which the burners 31-40 form. In addition, you may comprise the whole side wall 18C of the spheroidizing furnace 18 with the said refractory.

  Although not shown, a water cooling jacket for cooling the side wall 18C of the spheroidizing furnace 18 may be provided. Thereby, it can suppress that raw material powder adheres to the inner surface of the side wall 18C of the spheroidizing furnace 18.

The raw material powder supply path 19 is connected to the raw material feeder 17 and the upper end 18 </ b> A (top) of the spheroidizing furnace 18. The raw material powder supply path 19 is a path for supplying the raw material powder supplied from the raw material feeder 17 to the upper end 18 </ b> A side of the spheroidizing furnace 18.
A plurality of raw material dispersion holes 20 are provided at the upper end 18A of the spheroidizing furnace 18. The plurality of raw material dispersion holes 20 are exposed to the raw material powder supply path 19. The plurality of raw material dispersion holes 20 are holes for dispersing the raw material powder supplied from the raw material powder supply path 19 in the spheroidizing furnace 18.

  In the present embodiment, the case where a plurality of raw material dispersion holes 20 are provided in the upper end 18A of the spheroidizing furnace 18 has been described as an example. A raw material dispersion plate (not shown) in which the raw material dispersion holes 20 are formed may be prepared, and the raw material dispersion plate may be disposed at the upper end of the spheroidizing furnace.

The combustion chambers 21 to 25 are provided outside the side wall 18 </ b> C of the spheronization furnace 18 located between the upper end 18 </ b> A of the spheronization furnace 18 and the bottom 18 </ b> B of the spheronization furnace 18.
The combustion chamber 21 is disposed on the upper end 18 </ b> A side of the spheroidizing furnace 18. The combustion chamber 21 is a combustion chamber arranged in the uppermost layer among the combustion chambers 21 to 25.

  The combustion chamber 21 has a first flame accommodating area 21A in which the flame of the burner 31 is accommodated, and a second flame accommodating area 21B in which the flame of the burner 32 is accommodated and arranged opposite to the first flame accommodating area 21A. And a donut-shaped space 21C integrated with the first and second flame accommodating areas 21A. The space 21 </ b> C exposes the outer surface 18 a of the side wall 18 </ b> C of the spheronization furnace 18 in the circumferential direction of the spheronization furnace 18.

  The combustion chambers 22 to 25 have the same configuration as the combustion chamber 21. That is, the combustion chambers 22 to 25 have a first flame accommodating region 21A, a second flame accommodating region 21B, and a space 21C. The combustion chambers 22 to 25 expose the outer surface 18 a of the side wall 18 </ b> C of the spheronization furnace 18 in the circumferential direction of the spheronization furnace 18.

  The combustion chamber 22 is disposed immediately below the combustion chamber 21. The combustion chamber 23 is disposed immediately below the combustion chamber 22. The combustion chamber 24 is disposed immediately below the combustion chamber 23. The combustion chamber 25 is disposed immediately below the combustion chamber 24. The combustion chamber 25 is a combustion chamber arranged in the lowest layer among the combustion chambers 21 to 25.

  In the present embodiment, the case where five combustion chambers 21 to 25 are arranged in the vertical direction has been described as an example. However, the number of combustion chambers can be appropriately selected as necessary. It is not limited. That is, the number of combustion chambers may be two or more.

The burner 31 is provided in the combustion chamber 21 such that the tip that forms the flame is exposed to the first flame accommodating region 21 </ b> A of the combustion chamber 21. The burner 31 branches from the combustion-supporting gas supply line 13 </ b> A and is connected to the combustion-supporting gas supply source 13 through a branch line provided with a combustion-supporting gas flow rate adjustment valve 51.
The burner 31 branches from the fuel gas supply line 15 </ b> A and is connected to the fuel gas supply source 15 through a branch line provided with a fuel gas flow rate adjustment valve 61.

  The burner 32 is provided in the combustion chamber 21 such that the tip that forms the flame is exposed to the second flame accommodating region 21 </ b> B of the combustion chamber 21. Thereby, the burners 31 and 32 are arranged to face each other via the spheroidizing furnace 18. The burner 32 branches from the combustion-supporting gas supply line 13 </ b> A and is connected to the combustion-supporting gas supply source 13 through a branch line provided with a combustion-supporting gas flow rate adjustment valve 52.

The burner 32 branches from the fuel gas supply line 15 </ b> A, and is connected to the fuel gas supply source 15 through a branch line provided with a fuel gas flow rate adjustment valve 62.
The burners 31 and 32 generate combustion gas containing almost no unburned fuel gas in the fuel chamber 21 by completely burning the fuel gas (fuel) and the combustion-supporting gas.

The burner 33 is provided in the combustion chamber 22 such that the tip that forms the flame is exposed to the first flame accommodating region 21 </ b> A of the combustion chamber 22. The burner 33 branches from the combustion-supporting gas supply line 13 </ b> A and is connected to the combustion-supporting gas supply source 13 via a branch line provided with a combustion-supporting gas flow rate adjustment valve 53.
The burner 33 is branched from the fuel gas supply line 15 </ b> A, and is connected to the fuel gas supply source 15 via a branch line provided with a fuel gas flow rate adjustment valve 63.

  The burner 34 is provided in the combustion chamber 22 such that the tip that forms the flame is exposed to the second flame accommodating region 22 </ b> B of the combustion chamber 22. Thereby, the burners 33 and 34 are arranged to face each other via the spheroidizing furnace 18. The burner 34 branches from the combustion-supporting gas supply line 13 </ b> A and is connected to the combustion-supporting gas supply source 13 through a branch line provided with a combustion-supporting gas flow rate adjustment valve 54.

The burner 34 is branched from the fuel gas supply line 15 </ b> A and is connected to the fuel gas supply source 15 via a branch line provided with a fuel gas flow rate adjustment valve 64.
The burners 33 and 34 generate combustion gas containing almost no unburned fuel gas in the fuel chamber 22 by completely burning the fuel gas (fuel) and the combustion-supporting gas.

The burner 35 is provided in the combustion chamber 23 such that the tip that forms the flame is exposed to the first flame accommodating region 21 </ b> A of the combustion chamber 23. The burner 35 branches from the combustion-supporting gas supply line 13 </ b> A, and is connected to the combustion-supporting gas supply source 13 through a branch line provided with a combustion-supporting gas flow rate adjustment valve 55.
The burner 35 branches from the fuel gas supply line 15 </ b> A and is connected to the fuel gas supply source 15 via a branch line provided with a fuel gas flow rate adjustment valve 65.

  The burner 36 is provided in the combustion chamber 23 such that the tip that forms the flame is exposed to the second flame accommodating region 22B of the combustion chamber 23. Thereby, the burners 35 and 36 are arranged to face each other via the spheroidizing furnace 18. The burner 36 branches from the combustion-supporting gas supply line 13A and is connected to the combustion-supporting gas supply source 13 via a branch line provided with a combustion-supporting gas flow rate adjustment valve 56.

The burner 36 branches from the fuel gas supply line 15A and is connected to the fuel gas supply source 15 via a branch line provided with a fuel gas flow rate adjustment valve 66.
The burners 35 and 36 generate combustion gas containing almost no unburned fuel gas in the fuel chamber 23 by completely burning the fuel gas (fuel) and the combustion-supporting gas.

The burner 37 is provided in the combustion chamber 24 such that the tip that forms the flame is exposed to the first flame accommodating region 21 </ b> A of the combustion chamber 24. The burner 37 branches from the combustion-supporting gas supply line 13 </ b> A, and is connected to the combustion-supporting gas supply source 13 via a branch line provided with a combustion-supporting gas flow rate adjustment valve 57.
The burner 37 is branched from the fuel gas supply line 15 </ b> A, and is connected to the fuel gas supply source 15 through a branch line provided with a fuel gas flow rate adjustment valve 67.

  The burner 38 is provided in the combustion chamber 24 so that the tip that forms the flame is exposed to the second flame accommodating region 22B of the combustion chamber 24. Thereby, the burners 37 and 38 are arranged to face each other via the spheroidizing furnace 18. The burner 38 branches from the combustion-supporting gas supply line 13A and is connected to the combustion-supporting gas supply source 13 via a branch line provided with a combustion-supporting gas flow rate adjustment valve 58.

The burner 38 is branched from the fuel gas supply line 15A and is connected to the fuel gas supply source 15 via a branch line provided with a fuel gas flow rate adjustment valve 68.
The burners 37 and 38 generate combustion gas containing almost no unburned fuel gas in the fuel chamber 24 by completely burning the fuel gas (fuel) and the combustion-supporting gas.

The burner 39 is provided in the combustion chamber 25 such that the tip that forms the flame is exposed to the first flame accommodating region 21 </ b> A of the combustion chamber 25. The burner 39 branches from the combustion-supporting gas supply line 13 </ b> A and is connected to the combustion-supporting gas supply source 13 through a branch line provided with a combustion-supporting gas flow rate adjustment valve 59.
The burner 39 branches from the fuel gas supply line 15 </ b> A and is connected to the fuel gas supply source 15 via a branch line provided with a fuel gas flow rate adjustment valve 69.

  The burner 40 is provided in the combustion chamber 25 so that the tip that forms the flame is exposed to the second flame accommodating region 22B of the combustion chamber 25. Thereby, the burners 39 and 40 are arranged to face each other via the spheroidizing furnace 18. The burner 40 branches from the combustion-supporting gas supply line 13 </ b> A and is connected to the combustion-supporting gas supply source 13 via a branch line provided with a combustion-supporting gas flow rate adjustment valve 60.

The burner 40 branches from the fuel gas supply line 15A and is connected to the fuel gas supply source 15 via a branch line provided with a fuel gas flow rate adjustment valve 70.
The burners 39 and 40 generate combustion gas containing almost no unburned fuel gas in the fuel chamber 25 by completely burning the fuel gas (fuel) and the combustion-supporting gas.

For example, the burners 31 to 40 can have the same configuration (in other words, burners having the same configuration are used). In this case, as the burners 31 to 40, for example, a premix type burner is preferable if soot mixing is suppressed, but if it is desired to avoid the risk of flashback, a diffusion combustion type burner may be used. Is possible.
In addition, you may combine various kinds of burners as needed.

  Moreover, the quantity of the combustion gas which the flame of the burners 31-40 produces | generates is adjusted with the flow volume of fuel gas, and the flow volume of combustion support gas. Further, the flow rate of the combustion-supporting gas is the same as or more than the amount necessary for complete combustion of the fuel gas.

  A plurality of combustion gas introduction holes 45 (four in the case of the present embodiment) are provided so as to penetrate the outer wall 18C of the spheroidizing furnace 18 where the space C of the combustion chamber 21 is exposed. The combustion gas introduction hole 45 is a hole for introducing the combustion gas generated in the combustion chamber 21 into the spheroidizing furnace 18.

The plurality of combustion gas introduction holes 45 are arranged at predetermined intervals in the circumferential direction of the spheroidizing furnace 18. Further, the plurality of combustion gas introduction holes 45 are arranged at positions separated from the flame formed by the burners 31 and 32.
As described above, by providing the plurality of combustion gas introduction holes 45 at positions separated from the flame formed by the burners 31 and 32, the plurality of combustion gas introduction holes 45 are provided in the vicinity of the flame formed by the burners 31 and 32. Compared to the case, introduction of unburned fuel gas into the spheronization furnace 18 can be suppressed.

  A plurality (four in the present embodiment) of the combustion gas introduction holes 46 are provided so as to penetrate the outer wall 18C of the spheroidizing furnace 18 where the space C of the combustion chamber 22 is exposed. The combustion gas introduction hole 46 is a hole for introducing the combustion gas generated in the combustion chamber 22 into the spheroidizing furnace 18.

The plurality of combustion gas introduction holes 46 are arranged at predetermined intervals in the circumferential direction of the spheroidizing furnace 18. Further, the plurality of combustion gas introduction holes 46 are arranged at positions separated from the flame formed by the burners 33 and 34.
As described above, by providing the plurality of combustion gas introduction holes 46 at positions separated from the flame formed by the burners 33 and 34, the plurality of combustion gas introduction holes 46 are provided in the vicinity of the flame formed by the burners 33 and 34. Compared to the case, introduction of unburned fuel gas into the spheronization furnace 18 can be suppressed.

  A plurality (four in this embodiment) of the combustion gas introduction holes 47 are provided so as to penetrate the outer wall 18C of the spheroidizing furnace 18 where the space C of the combustion chamber 23 is exposed. The combustion gas introduction hole 47 is a hole for introducing the combustion gas generated in the combustion chamber 23 into the spheroidizing furnace 18.

The plurality of combustion gas introduction holes 47 are arranged at predetermined intervals in the circumferential direction of the spheroidizing furnace 18. Further, the plurality of combustion gas introduction holes 47 are arranged at positions separated from the flame formed by the burners 35 and 36.
As described above, the plurality of combustion gas introduction holes 47 are provided in the vicinity of the flame formed by the burners 35 and 36 by providing the plurality of combustion gas introduction holes 47 at positions separated from the flame formed by the burners 35 and 36. Compared to the case, introduction of unburned fuel gas into the spheronization furnace 18 can be suppressed.

  A plurality (four in this embodiment) of the combustion gas introduction holes 48 are provided so as to penetrate the outer wall 18C of the spheroidizing furnace 18 where the space C of the combustion chamber 24 is exposed. The combustion gas introduction hole 48 is a hole for introducing the combustion gas generated in the combustion chamber 24 into the spheroidizing furnace 18.

The plurality of combustion gas introduction holes 48 are arranged at predetermined intervals in the circumferential direction of the spheroidizing furnace 18. Further, the plurality of combustion gas introduction holes 48 are arranged at positions separated from the flame formed by the burners 37 and 38.
As described above, by providing the plurality of combustion gas introduction holes 48 at positions separated from the flame formed by the burners 37 and 38, the plurality of combustion gas introduction holes 48 are provided in the vicinity of the flame formed by the burners 37 and 38. Compared to the case, introduction of unburned fuel gas into the spheronization furnace 18 can be suppressed.

  A plurality (four in the present embodiment) of the combustion gas introduction holes 49 are provided so as to penetrate the outer wall 18C of the spheroidizing furnace 18 in which the space C of the combustion chamber 25 is exposed. The combustion gas introduction hole 49 is a hole for introducing the combustion gas generated in the combustion chamber 25 into the spheroidizing furnace 18.

The plurality of combustion gas introduction holes 49 are arranged at predetermined intervals in the circumferential direction of the spheroidizing furnace 18. Further, the plurality of combustion gas introduction holes 49 are arranged at positions separated from the flame formed by the burners 39 and 40.
Thus, by providing the plurality of combustion gas introduction holes 49 at positions separated from the flame formed by the burners 39, 40, the plurality of combustion gas introduction holes 49 are provided in the vicinity of the flame formed by the burners 39, 40. Compared to the case, introduction of unburned fuel gas into the spheronization furnace 18 can be suppressed.

  The combustion gas introduction holes 45 to 49 described above are formed such that the extending direction of the combustion gas introduction holes 45 to 49 is the same as the normal direction of the spheroidizing furnace 18.

In FIG. 3, as an example, the case where four combustion gas introduction holes 45 to 49 are provided in the circumferential direction of the spheronization furnace 18 is described as an example. However, the combustion arranged in the circumferential direction of the spheronization furnace 18 is described. The number of the gas introduction holes 45 to 49 is not limited to this.
In FIG. 3, as an example of the combustion gas introduction holes 45 to 49, the case where the combustion gas introduction holes 45 to 49 are provided only in the circumferential direction of the spheroidizing furnace 18 is described as an example. You may provide the holes 45-49 in the circumferential direction of the spheroidizing furnace 18, and the extending direction (vertical direction) of the spheroidizing furnace 18, respectively.

  Thus, the outer surface 18a of the side wall 18C of the spheroidizing furnace 18 is exposed to the outside of the side wall 18C of the spheroidizing furnace 18 located between the upper end 18A of the spheroidizing furnace 18 and the bottom 18B of the spheroidizing furnace 18. And the combustion chambers 21-25 arrange | positioned with respect to the extending direction (vertical direction) of the spheroidizing furnace 18, and the burners 31- provided in the combustion chambers 21-25 and forming a flame in the combustion chambers 21-25. 40 and the combustion gas introduction holes 45 through the side walls 18C of the spheroidizing furnace 18 where the combustion chambers 21-25 are exposed, and leading the combustion gas in the combustion chambers 21-25 generated by the flame into the spheroidizing furnace 18. 49, the fuel gas is sufficiently burned by the burners 31 to 40 in the combustion chambers 21 to 25 provided outside the spheroidizing furnace 18, and contains almost no unburned fuel gas. Can generate and That.

  Thereby, the dispersed raw material powder is melted by the combustion gas containing almost no unburned fuel gas introduced into the spheroidizing furnace 18 through the combustion gas introduction holes 45 to 49, and the spheroidized particles are formed. Since it becomes possible to produce | generate, the quantity of the carbon adhering to and mixing in a spheroidized particle can be reduced.

Further, the combustion chambers 21 to 25 are provided so as to expose the outer surface 18a of the side wall 18C of the spheroidizing furnace 18 and are arranged with respect to the extending direction (vertical direction) of the spheroidizing furnace 18, and the combustion chambers 21 to 21 25 and the burners 31 to 40 that form flames in the combustion chambers 21 to 25, it is possible to reduce temperature variations in the spheroidizing furnace 18 in the vertical direction.
This makes it possible to lengthen the time that the raw material powder stays in the high-temperature combustion gas, so that even when a high melting point raw material powder (for example, zirconium) is used, stable shaped spheroidized particles are generated. it can.

  The temperature detectors 75 to 80 are in the spheroidizing furnace 18, and in the vertical direction below the inner surface 18 b (reference plane) of the wall constituting the upper end of the spheroidizing furnace 18, the temperature detector 75 and the temperature detector 76. The temperature detector 77, the temperature detector 78, the temperature detector 79, and the temperature detector 80 are arranged in this order.

  Specifically, for example, the temperature detector 75 is disposed at a position 100 mm from the inner surface 18 b, the temperature detector 76 is disposed at a position 300 mm from the inner surface 18 b, and the temperature detector 77 is disposed at a position 600 mm from the inner surface 18 b. The temperature detector 78 can be disposed at a position 900 mm from the inner surface 18b, the temperature detector 79 can be disposed at a position 1200 mm from the inner surface 18b, and the temperature detector 80 can be disposed at a position 1450 mm from the inner surface 18b.

  The temperature detectors 75 to 80 are each electrically connected to the control unit 82. The temperature detectors 75 to 80 transmit the detected temperatures in the spheroidizing furnace 18 to the control unit 82. As the temperature detectors 75 to 80, for example, an R thermocouple (a high temperature thermocouple capable of detecting up to a temperature of about 1600 ° C.) can be used.

  In FIG. 3, the case where six temperature detectors are provided has been described as an example, but the number of temperature detectors is not limited to this. Moreover, the installation position of the temperature detectors 75 to 80 in the spheroidizing furnace 18 is not limited to the position of the temperature detectors 75 to 80 shown in FIG. 3, but a place that does not interfere with the generation of the spheroidized particles is preferable. .

The control unit 82 is electrically connected to the temperature detectors 75 to 80 in a state in which data regarding the temperature in the spheroidizing furnace 18 detected by the temperature detectors 75 to 80 can be received.
In addition, the control unit 82 can control the combustion-supporting gas flow rate adjustment valves 51 to 60 and the fuel gas flow-control valve 61 to 70, and can control the combustion-supporting gas flow rate adjustment valves 51 to 60 and the fuel gas flow rate adjustment valve 61. Electrically connected to .about.70.

  Based on the temperature detected by the temperature detectors 75 to 80, the control unit 82 has a temperature distribution in the spheroidizing furnace 18 according to the characteristics of the raw material powder to be melted (for example, the vertical distribution in the spheroidizing furnace 18). The opening degree of the combustion-supporting gas flow rate adjusting valves 51 to 60 and the fuel gas flow rate adjusting valves 61 to 70 is adjusted so that the temperature in the direction is uniform), and the spheroidizing furnace 18 is moved from the combustion chambers 21 to 25. Adjust the amount of combustion gas introduced.

  As described above, the temperature detectors 75 to 80 for detecting the temperature in the vertical direction in the spheroidizing furnace 18 and the combustion-supporting gas flow rate adjusting valve 51 to adjust the amount of the combustion-supporting gas supplied to the burners 31 to 40. 60, fuel gas flow rate adjustment valves 61 to 70 for adjusting the amount of fuel gas supplied to the burners 31 to 40, temperature detectors 75 to 80, combustion-supporting gas flow rate adjustment valves 51 to 60, and fuel gas flow rate adjustment And the control unit 82 electrically connected to the valves 61 to 70, and based on the temperature detected by the temperature detectors 75 to 80, the control unit 82 uses the combustion-supporting gas flow rate adjustment valves 51 to 60 and Since the amount of combustion gas introduced into the spheroidizing furnace 18 from the combustion chambers 21 to 25 can be adjusted by controlling the fuel gas flow rate adjusting valves 61 to 70, the vertical direction in the spheroidizing furnace 18 can be adjusted. By minimizing temperature variations That.

  This makes it possible to lengthen the residence time of the raw material powder in the high-temperature combustion gas, so that even when spherical particles are generated using a raw material powder having a large particle size as the raw material powder, the shape is Stable spheroidized particles can be obtained.

  By the way, the spheroidized particle manufacturing apparatus 10 of the present embodiment includes the combustion chambers 21 to 25 arranged in the vertical direction of the spheronization furnace 18 and the burners 31 to 40 provided in the combustion chambers 21 to 25. Therefore, the combustion-supporting gas flow rate adjustment valves 51 to 60, the fuel gas flow rate adjustment valves 61 to 70, the temperature detectors 75 to 80, and the control unit 82 provided in the spheroidized particle manufacturing apparatus 10 shown in FIGS. 1 and 3. Even when is removed from the components, it is possible to reduce the difference between the temperature in the lower part of the spheroidizing furnace 18 and the temperature in the upper part of the spheroidizing furnace 18.

  Therefore, since the residence time of the raw material powder in the high-temperature combustion gas can be extended, the shape is stable even when the raw material powder having a large particle size is used as the raw material powder. Spheroidized particles can be obtained.

The blown gas introduction portion 84 is provided at the bottom portion 18 </ b> B of the spheroidizing furnace 18. The blown gas introduction unit 84 is connected to the blower blower 87 and introduces the air sent from the blower blower 87 into the bottom 18 </ b> B of the spheroidizing furnace 18.
The spheroidized particle outlet 85 is provided on the side wall 18 </ b> C of the spheronizing furnace 18 at a portion located at the bottom 18 </ b> B of the spheronizing furnace 18 so as to face the blowing gas introduction part 84. The spheroidized particle derivation unit 85 derives the spheroidized particles from the spheroidizing furnace 18 by the air sent from the blower blower 87. The blower blower 87 is for supplying air to the blown gas introduction part 84.

The cooling gas inlet 88 is connected to the upper end of the cyclone 95. The cooling gas inlet 88 is an inlet for introducing a cooling gas (for example, air) into the spheroidized particle transport line 89 via the upper end of the cyclone 95.
Further, a blower (not shown) is provided at the rear stage of the bag filter 96, and the cooling gas is introduced from the cooling gas introduction port 88 by being sucked by the blower.

A filter (not shown) and a cooling gas adjusting unit (not shown) are provided at the cooling gas inlet 88. The cooling gas adjustment unit is for adjusting the amount of cooling gas introduced. As the cooling gas adjusting unit, for example, a damper can be used.
As described above, by using the damper as the cooling gas adjusting unit, the amount of the cooling gas introduced into the spheroidized particle transport line 89 can be adjusted by adjusting the angle of the damper.

Further, by adjusting the amount of air introduced from the blower 87 and the amount of cooling gas introduced from the cooling gas introduction port 88 to change the amount of air introduced into the cyclone 95, the spherical shape collected by the cyclone 95 and the bag filter 96 is collected. The particle size distribution of the particles can be changed.
Moreover, the particle size of the spheroidized particles collected by the cyclone 95 can be reduced by increasing the amount of air blown from the blower blower 87 and increasing the flow velocity of the gas transporting the spheroidized particles.

  The spheroidized particle transport line 89 has one end connected to the upper end of the cyclone 95 and the other end connected to the bag filter 96.

The spheroidized particle collecting device 91 is a device that collects the spheroidized particles derived from the spheroidized particle deriving unit 85, and includes a cyclone 95 and a bag filter 96.
The cyclone 95 is provided on the downstream side of the spheroidizing furnace 18, and is connected to the bottom 18 </ b> B of the spheronizing furnace 18 via the spheroidizing particle outlet 85. The cyclone 95 collects the spheroidized particles having the first particle diameter among the spheroidized particles transported via the spheroidized particle outlet 85. The spheroidized particles having the first particle diameter are collected from the lower end of the cyclone 95. The first particle diameter is larger than the second particle diameter described later.

  The bag filter 96 is provided on the downstream side of the cyclone 95, and is connected to the upper end of the cyclone 95 via a spheroidized particle transport line 89. The bag filter 96 collects spheroidized particles having a second particle size smaller than the first particle size.

  According to the spheroidizing particle production apparatus of the present embodiment, the spheronizing furnace 18 is disposed outside the side wall 18C of the spheronizing furnace 18 located between the upper end 18A of the spheronizing furnace 18 and the bottom 18B of the spheronizing furnace 18. Are exposed to the outer surface 18a of the side wall 18C and disposed in the extending direction (vertical direction) of the spheroidizing furnace 18, and are provided in the combustion chambers 21 to 25, and are provided in the combustion chambers 21 to 25. The burner 31-40 which forms a flame in 25, and the side wall 18C of the spheroidizing furnace 18 where the combustion chambers 21-25 are exposed, the combustion gas in the combustion chambers 21-25 generated by the flame is spheronized furnace The combustion gas introduction holes 45 to 49 led into the combustion chamber 18 are sufficiently burned by the burners 31 to 40 in the combustion chambers 21 to 25 provided outside the spheroidizing furnace 18. Contains almost no fuel gas It is possible to produce a baked gas.

  Thereby, the dispersed raw material powder is melted by the combustion gas containing almost no unburned fuel gas introduced into the spheroidizing furnace 18 through the combustion gas introduction holes 31 to 40, and the spheroidized particles are formed. Since it becomes possible to produce | generate, the quantity of the carbon adhering to and mixing in a spheroidized particle can be reduced.

  Further, the combustion chambers 21 to 25 are provided so as to expose the outer surface 18a of the side wall 18C of the spheroidizing furnace 18 and are arranged with respect to the extending direction (vertical direction) of the spheroidizing furnace 18, and the combustion chambers 21 to 21 25 and the burners 31 to 40 that form flames in the combustion chambers 21 to 25, it is possible to reduce temperature variations in the spheroidizing furnace 18 extending in the vertical direction. .

  This makes it possible to lengthen the time that the raw material powder stays in the high-temperature combustion gas, so that even when a high melting point raw material powder (for example, zirconium) is used, stable shaped spheroidized particles are generated. it can.

Next, spheroidized particles are generated by the following method for the spheroidized particle manufacturing method using the spheroidized particle manufacturing apparatus 10 configured as described above.
First, the fuel gas and the combustion-supporting gas are supplied to the burners 31 to 40, and the fuel gas is completely burned in the combustion chambers 21 to 25, thereby generating a combustion gas containing almost no unburned fuel gas. The combustion gas is introduced into the spheroidizing furnace 18 through the combustion gas introduction holes 45 to 49.

Next, the temperature detectors 75 to 80 detect the temperature in the vertical direction in the spheroidizing furnace 18, and based on the detected temperature, the controller in the vertical direction in the spheroidizing furnace 18 becomes uniform. 82, the flow rates of the combustion-supporting gas and the fuel gas supplied to the burners 31 to 40 are adjusted.
In addition, what is necessary is just to perform adjustment of the flow volume of the combustion support gas supplied to the burners 31-40 and fuel gas as needed.

  Next, the raw material powder is dispersed into the spheroidizing furnace 18 from the upper end 18A of the spheroidizing furnace 18 through the plurality of raw material dispersion holes 20 in a state where the temperature in the vertical direction in the spheroidizing furnace 18 is uniform. .

Thereafter, the raw material powder is melted by the combustion gas introduced into the spheroidizing furnace 18 and having a uniform vertical temperature, and spheroidized particles are generated.
The produced spheroidized particles are collected by a cyclone 95 and a bag filter 96 constituting the spheroidized particle collecting device 91.

  At this time, the cyclone 95 collects the spheroidized particles having the first particle size out of the spheroidized particles, and the bag filter 96 collects the second spheroidized particles that are smaller than the first particle size. The spheroidized particles having a particle size of are collected.

  According to the method for producing spheroidized particles of the present embodiment, the combustion gas present in the combustion chambers 21 to 25 generated by the flames of the burners 31 to 40 is introduced into the spheronization furnace 18 and the raw material is produced by the combustion gas. By fusing powder to produce spheroidized particles, it becomes possible to produce spheroidized particles using combustion gas that contains almost no unburned fuel gas, so it adheres to spheroidized particles more than before. In addition, the amount of carbon mixed in can be reduced.

Further, the flow rates of the combustion-supporting gas and the fuel gas supplied to the burners 31 to 40 are adjusted so that the temperature in the vertical direction in the spheroidizing furnace 18 becomes uniform, and the spheroidizing furnace 18 enters from the combustion chambers 21 to 25. The amount of combustion gas to be introduced is adjusted, and then the raw material powder is dispersed in the spheroidizing furnace 18 through the plurality of raw material dispersion holes 22, and the raw material powder is melted by the combustion gas to be spheroidized. By generating particles, the difference between the temperature in the lower part of the spheroidizing furnace 18 and the temperature in the upper part of the spheroidizing furnace 18 becomes as small as possible, so that the residence time of the raw material powder in the high-temperature combustion gas can be increased. It becomes possible.
Therefore, even when spheroidized particles are generated using a material having a high melting point as a raw material powder (for example, zirconia (melting point is 2680 ° C.)), spheroidized particles having a stable shape can be obtained.

  In the present embodiment, as an example, the combustion-supporting gas flow rate adjustment valves 51 to 60 and the fuel gas flow rate adjustment valves 61 to 70 are controlled so that the temperature in the vertical direction in the spheronization furnace 18 is uniform. Although the case has been described as an example, depending on the characteristics of the raw material powder, an optimal temperature distribution for spheroidizing the raw material powder may be formed in the spheroidizing furnace 18.

  For example, by setting the temperature in the vicinity of the raw material dispersion holes 20 to a low temperature (for example, a temperature equal to or lower than the melting point of the raw material powder), the raw material is uniformly dispersed in the spheroidizing furnace 18 without being fused while preheating the raw material. The raw material powder can be prevented from coarsening due to granulation by adjusting the temperature so as to reach a temperature equal to or higher than the melting point of the raw material powder from a certain distance from the raw material dispersion hole 20. Can be efficiently spheroidized.

  In addition, the present invention independently controls the burners 31 to 40 provided in the combustion chambers 21 to 25 so that a temperature distribution suitable for melting the raw material powder is formed in the spheroidizing furnace 18. Thus, the present invention is applicable when the amount of combustion gas generated in the combustion chambers 21 to 25 is different.

  In addition, the combustion-supporting gas flow rate adjustment valves 51 to 60, the fuel gas flow rate adjustment valves 61 to 70, the temperature detectors 75 to 80, and the control unit 82 provided in the spheroidized particle manufacturing apparatus 10 shown in FIGS. In the case of producing spheroidized particles using the spheroidized particle production apparatus from which the components are removed, the step of adjusting the flow rate of the combustion-supporting gas and the fuel gas supplied to the burners 31 to 40 by the control unit 82 is excluded. Except for the above, the spheroidized particles can be generated by the same method as the spheroidized particle manufacturing method using the spheroidized particle manufacturing apparatus 10.

  The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited to such specific embodiments, and within the scope of the present invention described in the claims, Various modifications and changes are possible.

  FIG. 4 is a cross-sectional view for explaining another example of the combustion gas introduction hole. In FIG. 4, the same components as those of the structure shown in FIG.

  In the present embodiment, the case where the extending direction of the plurality of combustion gas introduction holes 45 is the same as the normal direction of the spheroidizing furnace 18 has been described with reference to FIG. 2, but the plurality of combustion illustrated in FIG. Instead of the gas introduction holes 45, as shown in FIG. 4, a plurality of combustion gas introduction holes 97 whose extending directions are the same as the tangential direction of the spheronization furnace 18 are provided on the side wall 18C of the spheronization furnace 18. Also good.

Further, in place of the combustion gas introduction holes 46 to 49 provided in the combustion chambers 22 to 25, a plurality of combustions whose extending direction is the same as the tangential direction of the spheronization furnace 18 in the side wall 18 </ b> C of the spheronization furnace 18. A gas introduction hole 97 may be provided.
Although not shown, the combustion gas introduction holes 45 to 49 may have a structure capable of supplying combustion gas obliquely downward.

  Thus, the extending direction of the plurality of combustion gas introduction holes 45 to 49 for supplying the combustion gas into the spheronization furnace 18 is set to the same direction as the tangential direction of the spheronization furnace 18, or the combustion gas introduction holes 45 to 45 are arranged. 49 has a shape capable of supplying combustion gas obliquely downward, a strong swirl flow can be generated by the combustion gas supplied into the spheroidizing furnace 18, so that the temperature in the spheronizing furnace 18 can be increased. And the raw material powder can be uniformly dispersed in the spheroidizing furnace 18.

  FIG. 5 is a cross-sectional view for explaining a modification of the structure shown in FIG. In FIG. 5, the same components as those of the structure shown in FIG.

In the present embodiment, the case where the combustion chamber 21 in which two burners (in other words, a pair of burners 31 and 32) can be disposed is described as an example with reference to FIG. As shown in FIG. 4, a combustion chamber 98 in which four burners (in other words, two burners 31 and 32, respectively) can be arranged is prepared, and the combustion chamber 98 may be provided with four burners.
In this case, it is preferable to use four combustion chambers 98 instead of the combustion chambers 22 to 25 and to provide four burners for each of the four combustion chambers.

  This makes it possible to further increase the temperature of the combustion gas, which is particularly effective when spheroidizing a raw material powder having a high melting point. The number of burners provided in the combustion chamber used in the present invention is not limited to FIGS.

Example 1
In Example 1, the temperature in the vertical direction in the spheroidizing furnace 18 was measured using the spheroidized particle manufacturing apparatus 10 having the structure shown in FIGS. 1, 3, and 4. At this time, the temperature detector 75 is arranged at a position 100 mm from the inner surface 18b of the wall constituting the upper end 18A of the spheroidizing furnace 18, the temperature detector 76 is arranged at a position 300 mm from the inner surface 18b, and 600 mm from the inner surface 18b. A temperature detector 77 is disposed at a position, a temperature detector 78 is disposed at a position 900 mm from the inner surface 18b, a temperature detector 79 is disposed at a position 1200 mm from the inner surface 18b, and a temperature detector is disposed at a position 1450 mm from the inner surface 18b. 80 was placed.

The burners 31 to 40 were supplied with 1 Nm ³ / h of LPG as a fuel gas and 5 Nm ³ / h of oxygen as a combustion-supporting gas.
The result of the temperature distribution in the vertical direction in the spheroidizing furnace 18b at this time is shown in FIG. FIG. 6 is a diagram showing the temperature distribution in the vertical direction in the spheroidizing furnace of Example 1 and Reference Example 1. FIG.

(Reference Example 1)
In Reference Example 1, the temperature in the vertical direction in the spheroidizing furnace 18 was measured using the spheroidized particle manufacturing apparatus 140 having the structure shown in FIGS. 10 and 11. At this time, the temperature detector 75 is disposed at a position 100 mm from the inner surface 147b of the wall constituting the upper end 147A of the spheroidizing furnace 147, the temperature detector 76 is disposed at a position 300 mm from the inner surface 147b, and 600 mm from the inner surface 147b. The temperature detector 77 is disposed at a position, the temperature detector 78 is disposed at a position 900 mm from the inner surface 147b, the temperature detector 79 is disposed at a position 1200 mm from the inner surface 147b, and the temperature detector is disposed at a position 1450 mm from the inner surface 147b. 80 was placed.
Further, the burner 152-1 and 152-2, the LPG as a fuel gas ^{5 Nm} 3 / h, and was supplied with oxygen 25 Nm ³ / h as a combustion-supporting gas.
FIG. 6 shows the result of the temperature distribution in the vertical direction in the spheroidizing furnace 147 at this time.

(About temperature distribution in the spheroidizing furnace of Example 1 and Reference Example 1)
Referring to FIG. 6, in Reference Example 1, it was confirmed that the temperature in the spheroidizing furnace 147 decreased from the upper end 147A of the spheroidizing furnace 147 toward the lower side.

In Reference Example 1, when the flow rate of LPG and the flow rate of oxygen were increased with these flow rate ratios kept constant to increase the amount of combustion gas, as the amount of combustion gas increased, The temperature drop was slightly improved.
However, since the gas flow rate in the spheroidizing furnace 147 is increased, there is a disadvantage that the residence time of the raw material powder in the furnace is shortened.

  Moreover, when the installation position of the burners 152-1 and 152-2 in the vertical direction of the spheroidizing furnace 147 was changed to be around the middle of the spheroidizing furnace 147, an extreme temperature drop in the lower part of the spheroidizing furnace 147 was observed. However, it was difficult to make the temperature in the spheroidizing furnace 147 uniform because a temperature peak occurred in the vicinity of the installation positions of the burners 152-1 and 152-2.

  On the other hand, as shown in FIG. 6, in the case of Example 1, it was confirmed that a substantially uniform temperature could be achieved in the vertical direction in the spheroidizing furnace 18.

(Example 2)
In Example 2, the spheroidized particle production apparatus 10 shown in FIG. 1 is used and glass powder is used as a raw material powder to produce spheroidized particles, and the adhesion state of black foreign matter (carbon) is measured using an optical microscope. evaluated.
At this time, the structure shown in FIG. 4 (in other words, the spheroidizing furnace 18 provided with a plurality of combustion gas introduction holes 97) was used.

Hereinafter, a method for producing the spheroidized particles in Example 2 will be described.
First, LPG is supplied to the burners 31 to 40 at a supply amount of 1 Nm ³ / h as fuel gas, and oxygen is supplied as a combustion-supporting gas at a supply amount of 5 Nm ³ / h to form a flame. Produced combustion gas.

  Next, the glass powder is transported to the upper end 18A of the spheronization furnace 18 by a carrier gas (oxygen) at a supply rate of 20 kg / h, and the combustion introduced into the spheronization furnace 18 through the plurality of combustion gas introduction holes 97. Spherical particles were generated by melting the glass powder using gas, and then the spherical particles were collected.

Next, a method for measuring the amount of carbon attached to the spheroidized particles will be described.
20 g of spheroidized particles are spread thinly to a size of 40 mm × 60 mm, and then observed 20 times with a 20 × magnification (changing the observation location) using an optical microscope, and a black foreign object in one field of view. Was counted, and the average number of black foreign objects of 20 times was determined.
As a result, in Example 2, three black foreign objects could be observed on average.

(Comparative Example 1)
In Comparative Example 1, the same evaluation as in Example 2 was performed using the spheroidized particle manufacturing apparatus 120 shown in FIG. As the burner 124 of the spheroidized particle production apparatus 120, the burner 100 for producing spherical particles shown in FIGS. 7 and 8 was used.

Hereinafter, a method for producing spheroidized particles will be described.
LPG was supplied to the burner 124 at a supply rate of 1 Nm ³ / h as fuel gas, and oxygen was supplied as a combustion-supporting gas at a supply rate of 5 Nm ³ / h to form a flame in the spheronization furnace 128. .

  Subsequently, the glass powder is transported to the spheroidizing furnace 128 at a supply rate of 20 kg / h by a carrier gas (oxygen), and is passed through a flame to melt the glass powder to generate spheroidized particles, and then Spheroidized particles were collected.

Thereafter, 20 g of the spheroidized particles were thinly spread to a size of 40 mm × 60 mm by the same method as in Example 2, and then the field of view was changed at a magnification of 20 times (changed the observation location) using an optical microscope. Observation was performed 20 times, the number of black foreign objects in one field of view was counted, and the average number of black foreign objects of 20 times was obtained.
As a result, in Comparative Example 1, 11 black foreign objects could be observed on average.

(Summary of evaluation results of the number of black foreign bodies)
From the observation result of the black foreign matter in Example 2 and Comparative Example 1, by using the spheroidized particle manufacturing apparatus 10 of the present invention, compared with the case where the conventional spheroidized particle manufacturing apparatus 120 is used to generate the spheroidized particles. Thus, it was confirmed that carbon adhering to and mixed in the spheroidized particles can be reduced.

  The present invention can suppress the adhesion and mixing of carbon to the spheroidized particles, and can produce a spheroidized particle having a stable shape even when a high melting point raw material powder is used. The present invention can be applied to a method for producing particles.

  DESCRIPTION OF SYMBOLS 10 ... Spherical particle manufacturing apparatus, 11 ... Carrier gas supply source, 11A ... Carrier gas supply line, 12, 14, 16 ... Valve, 13 ... Combustion gas supply source, 13A ... Combustion gas supply line, 15 ... Fuel gas supply source, 15A ... fuel gas supply line, 17 ... raw material feeder, 18 ... spheroidizing furnace, 18a ... outer surface, 18b ... inner surface, 18A ... upper end, 18B ... bottom surface, 18C ... side wall, 19 ... raw material powder supply path 20 ... Raw material dispersion holes, 21-25, 98 ... combustion chambers, 21A ... first flame accommodation area, 21B ... second flame accommodation area, 21C ... space, 31-40 ... burners, 45-49, 97 ... Combustion gas introduction hole, 51-60 ... Combustion gas flow rate adjustment valve, 61-70 ... Fuel gas flow rate adjustment valve, 75-80 ... Temperature detector, 82 ... Control part, 84 ... Blast gas introduction part, 85 ... Spherical shape Particle outlet unit, 87 Blowing blower, 88 ... air introducing port, 89 ... spheroidized particle transport lines, 91 ... spheroidized particle collection device, 95 ... cyclone, 96 ... bag filter

Claims (18)

Spheroidizing furnace that melts the raw material powder, spheroidizes the powder surface to produce spheroidized particles, and extends in the vertical direction;
A plurality of raw material dispersion holes provided at an upper end of the spheroidizing furnace and dispersing the raw material powder supplied to the spheroidizing furnace in the spheroidizing furnace;
Wherein provided on the outside of the side wall of the spherical furnace located between the bottom of the top and the spherical furnace spheroidizing furnace, a part of the inner wall is formed by the outer surface of the side wall of the spheroidizing furnace, and the A plurality of combustion chambers arranged in the extending direction of the spheroidizing furnace;
Are respectively provided to the plurality of combustion chambers, and a burner to form a flame in front Symbol combustion chamber,
And through the side wall of the spheroidizing furnace so as to communicate the said spherical furnace and said combustion chamber, a plurality of combustion gas guides the combustion gas in the combustion chamber generated by the flame to the spheroidizing furnace An apparatus for producing spheroidized particles, comprising an introduction hole. Wherein the plurality of spherical particles production apparatus according to claim 1, characterized in that it has a control unit for controlling independently the burner provided in the combustion chamber. Wherein the control unit, spherical particles production apparatus according to claim 2, wherein adjusting the amount of the combustion gas flame is generated in the burner provided in the plurality of combustion chambers. A fuel supply for supplying fuel to the burner provided in the plurality of combustion chambers,
A combustion-supporting gas source for supplying a combustion-supporting gas to the burner provided in the plurality of combustion chambers,
A plurality of temperature detectors arranged in the spheronization furnace and detecting the temperature in the vertical direction in the spheronization furnace;
Have
Wherein, based on the temperature in which a plurality of temperature detectors for detecting the amount of the fuel supplied to the burner provided in the plurality of combustion chambers, and adjusting the amount of the combustion supporting gas The spheroidized particle manufacturing apparatus according to claim 2 or 3, wherein   The spheroidized particle manufacturing apparatus according to any one of claims 1 to 4, wherein the plurality of combustion gas introduction holes are arranged at positions separated from the flame. The spheroidized particles according to any one of claims 1 to 5 , wherein the plurality of combustion gas introduction holes are arranged in a circumferential direction of the spheroidizing furnace and an extending direction of the spheroidizing furnace. manufacturing device. Each of the plurality of combustion chambers is provided with a plurality of the burners,
The spheroidized particle production apparatus according to any one of claims 1 to 6 , wherein a plurality of the burners are arranged to face each other with a central axis of the spheroidizing furnace interposed therebetween . The spheroidized particle manufacturing apparatus according to any one of claims 1 to 7 , wherein an extending direction of the plurality of combustion gas introduction holes is the same as a normal direction of the spheroidizing furnace. . The spheroidized particle manufacturing apparatus according to any one of claims 1 to 7 , wherein an extending direction of the plurality of combustion gas introduction holes is the same direction as a tangential direction of the spheroidizing furnace. The spheroidized particle manufacturing apparatus according to any one of claims 1 to 7 , wherein the plurality of combustion gas introduction holes have a structure capable of supplying the combustion gas obliquely downward. The spheroidizing particle producing apparatus according to any one of claims 1 to 10 , wherein a side wall of the spheroidizing furnace is made of a refractory. Provided at a portion located at the bottom of the front Symbol sphere Joka furnace, a blowing gas inlet for introducing the blowing gas into the spherical reduction furnace,
The portion located on the bottom of the front Symbol sphere Joka furnace, and the blowing gas introduction portion and is opposed, and spherical particles deriving unit that derives the spherical particles from the spheronizing furnace,
A spheroidizing particle collecting device for collecting the spheroidizing particles derived from the spheroidizing particle deriving unit;
The spheroidized particle manufacturing apparatus according to any one of claims 1 to 11 , characterized in that The spheroidized particle collecting device is connected to the spheroidized particle derivation unit, and a cyclone for collecting particles having a first particle diameter among the spheroidized particles,
A bag filter that is disposed downstream of the cyclone and collects particles having a second particle diameter smaller than the first particle diameter among the spheroidized particles;
Connecting the cyclone and the bag filter, and transporting a part of the spheroidized particles to the bag filter;
The spheroidized particle manufacturing apparatus according to claim 12, wherein: A cooling gas inlet for introducing a cooling gas into the spheroidized particle transport line;
A cooling gas adjusting unit which is provided at the cooling gas introduction port and adjusts the introduction amount of the cooling gas introduced into the spheroidized particle transport line;
The spheroidized particle manufacturing apparatus according to claim 13, wherein A spheroidized particle manufacturing method using the spheroidized particle manufacturing apparatus according to any one of claims 1 to 14 ,
The combustion gases produced in said plurality of combustion chamber is introduced into said spheroidizing furnace, the combustion gases, spherical particles, characterized in that to produce the raw material powder is melted spherical particles Production method. The method for producing spheroidized particles according to claim 15 , wherein the combustion gas is generated by completely burning fuel and combustion-supporting gas with the burner. As the temperature distribution suitable to melt the raw material powder is formed in the spheroidizing furnace, an amount of the fuel supplied to the burner provided in the plurality of combustion chambers and said combustion supporting The method for producing spheroidized particles according to claim 16 , wherein the amount of the characteristic gas is controlled independently. As the temperature in the vertical direction of the spheroidizing furnace is made uniform, controlled independently of the amount of the amount and the combustion supporting gas in the fuel supplied to the burner provided in the plurality of combustion chamber The method for producing spheroidized particles according to claim 16 .

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