JPH1143726A - Device for treating aluminum dross and method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an aluminum dross treating device which reforms residual ash after recovering metallic aluminum into high alumina raw material, by heating to high temp. while cooling electrodes. SOLUTION: The aluminum dross treating device uses a rotary arc furnace which generates arc between one pair of the electrodes 30, 40 and heats while rotating around an axis, as center, connecting the electrodes 30, 40, and reforms the residual ash remained in the rotary arc furnace after recovering the metallic aluminum from the aluminum dross into the high alumina raw material by again returning back into the rotary arc furnace. In such a case, cooling means 44a, 44b for cooling the electrodes 30, 40 in the rotary arc furnace and a supplying means 59 for supplying oxidizing gas into the rotary arc furnace so as to hold the inner part in the rotary arc furnace to oxidizing atmosphere, are provided, and the residual ash is reformed into the high alumina raw material by heating the residual ash under oxidizing atmosphere while cooling the electrodes 30, 40 with the cooling means 44a, 44b.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for heating residual ash after recovering aluminum from aluminum dross to reform it into a high alumina raw material (aluminum oxide).

[0002]

2. Description of the Related Art Aluminum dross generated when aluminum is dissolved contains a considerable amount of aluminum, and this aluminum is generally recovered by heat-treating aluminum dross. A process for heating an aluminum dross by using an arc furnace having two opposing electrodes and forming an arc between the electrodes in the furnace as shown in Japanese Patent Publication No. 6-504320 as a recovery device for aluminum. Devices are known.

[0003] This processing apparatus is configured to be rotatable or oscillating about a long axis, and promotes separation and recovery of aluminum from aluminum dross.
Also, the processing device requires a minimum arbitrary amount of plasma gas to fix the arc, and at least one electrode is provided with a small axial hole through which the plasma working gas and Ar, N ₂ , CH ₄ , C
O, CO ₂ or a mixed gas thereof is blown.

[0004] The above-described processing apparatus is a highly safe processing apparatus, unlike a plasma torch that requires a water cooling mechanism, because it does not need to cool the electrodes and does not cause steam explosion due to water leakage. When the aluminum dross is recovered by heating the aluminum dross using such a processing apparatus, since the residual ash containing aluminum nitride, aluminum chloride, and the like remains in the rotary arc furnace, the residual ash is heated under an acidic atmosphere. As a result, it was reformed into a high alumina raw material.

[0005]

However, in order to reform the residual ash after aluminum recovery into a high alumina raw material,
Since it is necessary to perform high-temperature heating in an oxidizing atmosphere as compared with the time of recovering the aluminum content, there has been a problem that the graphite electrode of the rotary arc furnace is significantly consumed unless the graphite electrode is cooled as in the related art.

Accordingly, the present invention has been made in view of the above-mentioned problems, and an object of the present invention is to heat an electrode at a high temperature in an acidic atmosphere while cooling the electrode.
An object of the present invention is to provide an aluminum dross treatment apparatus for reforming residual ash into a stable and harmless high alumina raw material.

[0007]

According to the first aspect of the present invention,
While generating an arc between a pair of electrodes, using a rotary arc furnace that heats while rotating about the electrodes as an axis, after recovering metallic aluminum from aluminum dross, residual ash remaining in the rotary arc furnace, Again using the rotary arc furnace, an aluminum dross processing apparatus for reforming into a high alumina raw material, a cooling means for cooling the electrodes of the rotary arc furnace, and maintaining the inside of the rotary arc furnace under an acidic atmosphere. Supply means for supplying an oxidizing gas into the rotary arc furnace, and heating the residual ash under an acidic atmosphere while cooling the electrode by the cooling means, thereby reducing the residual ash to high alumina. It is characterized by reforming into raw materials. As a result, the consumption of the electrodes can be significantly reduced, and the residual ash can be reformed into a high alumina raw material by oxidizing an aluminum compound such as aluminum nitride contained in the residual ash.

According to a second aspect of the present invention, in addition to the configuration of the first aspect, the cooling means is a water-cooled jacket provided outside the electrode sleeve of the rotary arc furnace. I do. Thereby, even in the event of a water leak, the cooling water does not enter the rotary arc furnace, so that an explosion accident can be prevented from occurring.

According to a third aspect of the present invention, in addition to the configuration of the first or second aspect, a discharging means for discharging the residual ash to the outside of the rotary arc furnace, and a fine particle size of the residual ash are provided. Crushing means for crushing and crushing the residual ash, and returning the crushed residual ash to the rotary arc furnace and heating it again to convert the residual ash into a high alumina raw material. It is characterized by quality. Thereby, since the reforming reaction from the residual ash to the high alumina raw material can be promoted, the reforming reaction time can be shortened.

According to a fourth aspect of the present invention, there is provided an aluminum dross for recovering metallic aluminum from aluminum dross by using a rotary arc furnace which generates an arc between a pair of electrodes and heats while rotating around the electrodes. A processing apparatus, comprising: a cooling unit that cools an electrode of the rotary arc furnace; and a supply unit that supplies an inert gas into the rotary arc furnace so as to keep the inside of the rotary arc furnace under an inert atmosphere. And heating the aluminum dross under an inert atmosphere while cooling the electrodes by the cooling means, thereby separating the metallic aluminum. As a result, the consumption of the electrodes can be reduced, and the loss due to oxidation of the metal aluminum is eliminated, so that the recovery rate of the metal aluminum can be increased.

According to a fifth aspect of the present invention, after a metal aluminum is recovered from an aluminum dross by using a rotary arc furnace that generates an arc between a pair of electrodes and heats while rotating about the electrodes, An aluminum dross processing method for modifying residual ash remaining in the rotary arc furnace into a high alumina raw material, wherein the rotary ash furnace is kept under an acidic atmosphere, and the residual ash is heated while cooling the electrodes. By doing so, the residual ash is reformed into a high alumina raw material. As a result, the consumption of the electrodes can be greatly reduced, and by oxidizing aluminum compounds such as aluminum nitride contained in the residual ash,
The residual ash can be reformed into a high alumina raw material.

According to a sixth aspect of the present invention, in addition to the method of the fifth aspect, the residual ash is discharged outside the rotary arc furnace, crushed and crushed, and then the crushed and crushed residue is removed. The ash is returned to the rotary arc furnace and heated to reform the residual ash into a high alumina raw material. Thereby, since the reforming reaction from the residual ash to the high alumina raw material can be promoted, the reforming reaction time can be shortened.

According to a seventh aspect of the present invention, there is provided an aluminum dross for recovering metallic aluminum from aluminum dross by using a rotary arc furnace which generates an arc between a pair of electrodes and heats while rotating about the electrodes. A method of processing, characterized in that metallic aluminum is separated from the aluminum dross by keeping the inside of the rotary arc furnace under an inert atmosphere and heating the aluminum dross while cooling the electrodes.
As a result, the consumption of the electrodes can be reduced, and the loss due to oxidation of the metal aluminum is eliminated, so that the recovery rate of the metal aluminum can be increased.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIG. 1, the aluminum dross processing apparatus according to the present embodiment includes a furnace main body 1, electrode means 3 and 4 for heating aluminum dross and its residual ash,
The apparatus includes a tilting means 2 for the furnace body 1 and a furnace lid opening / closing means 5 for opening and closing the lid 50 of the furnace body 1.

The above electrode means 3 and 4 are provided with electrode rods 30 and 4
0, and electrode rod holders 31 and 41 for holding the same. For example, the electrode rods 30 and 40 are made of graphite. Under the electrode holders 31 and 41, small carts 32 and 42 are provided, and the small carts 32 and 42 are provided with a pair of parallel guide bars 53.6.
7 so as to be movable. This guide bar 53
67 is formed by a screw rod,
The motor 66 is rotated by drive motors 530 and 670 provided in the motor 66. Thereby, the guide bar 53
The small carts 32 and 42 on which the electrode holders 31 and 41 are placed are moved on the guide bars 53 and 67 by the rotation of the 67 so that the electrode rods 30 and 40 are inserted into the furnace main body 1. When the guide bars 53 and 67 rotate in the reverse direction, the electrode rods 30 and 40 are pulled out of the furnace main body 1.

The tilting means 2 is, as shown in FIG.
Holding frame 15, connecting shaft 25, hydraulic cylinder 22, holding frame 21 for holding hydraulic cylinder 22, support rail 6
5 and a trolley 66 for tilting the furnace body 1. That is, the furnace main body 1 is held by an L-shaped holding frame 15 that surrounds the outer periphery of the furnace main body 1, and the holding frame 15 is supported on the furnace lid 50 via the horizontal support shaft 14. The table 13 is rotatably supported.
A hydraulic cylinder 22 is provided below the holding frame 15 via a connecting shaft 25.
2 is a holding frame 21 that is rotatable via a horizontal support shaft 23.
It is supported by.

A support rail 65 is installed on the right side of the holding frame 15 in a straight line. When the furnace main body 1 is tilted, the carriage 66 moves on and off the support rail 65. Thereby, as shown by the phantom line in FIG. 1, when the piston rod 24 is extended while rotating the hydraulic cylinder 22, the lower portion of the holding frame 15 is pushed up via the connecting shaft 25, and the furnace body 1 is It tilts around 14. The hydraulic cylinder 22 and the holding frame 21 are accommodated in a pit 20 provided below the holding frame 15.

Further, as shown in FIG.
5, a pair of driven rollers 16 and a driving motor 19
The driven roller 16 is provided with the annular rail 1.
The right side of the furnace main body 1 is supported via the base 2. In addition, a driving roller 18 that is rotationally driven by a driving motor 19 is pressed against the annular rail 12 to rotate the furnace body 1. As shown in FIG. 2B, a pair of driven rollers 16 is provided below the holding frame 15 so as to support the left side of the furnace body 1 via the annular rail 11. . In addition, holding frame 1
In the circumferential direction of 5, a plurality of guide rollers 17 are arranged to guide the furnace body 1 so that the furnace body 1 rotates at a fixed position. Since the furnace lid 50 is held by the carriage 51, as will be described later, the furnace lid 50 itself does not rotate even if the furnace main body 1 rotates around the axis by the drive of the drive motor 19. ing.

As shown in FIG. 3, the furnace lid opening / closing means 5 includes a cart 51 for holding the furnace lid 50 and an arc-shaped rail 6.
3 and a drive means for moving the truck 51 along the rails 63. By moving the truck 51, the furnace lid 50 is opened and closed. Also,
The driving means includes a driving motor 61 installed in the pit 60.
And a drive arm 62 for connecting the drive motor 61 and the carriage 51. The drive arm 62 is configured to turn around the base end by the driving force of the drive motor 61. Thereby, the furnace lid 50 is opened and closed by moving the carriage 51 along the rail 63 from the state of the solid line to the state of the virtual line in FIG.

As shown in FIG. 4, the furnace body 1 is made of a tubular body lined with a refractory material, and withstands heating of aluminum dross and residual ash by the electrode rods 30 and 40 inserted in the furnace body. I am getting it. Furnace body 1
An annular rail 11 or 12 is attached to the outer peripheral portion of the motor, and is rotated by the driving force of the driving motor 19, so that the aluminum dross and its residual ash can be efficiently heated. . An opening is provided on the right side of the furnace body 1 on the paper surface, and an electrode sleeve 45 is attached to the opening. A water-cooling jacket 44a and a disaster prevention plate 43 constituting cooling means are attached to the outer end of the electrode sleeve 45 (outside the furnace body 1). The water-cooled jacket 44a is
0 is reduced. Further, the electrode rod 40 is inserted into the furnace through the disaster prevention plate 43, the water cooling jacket 44a, and the electrode sleeve 45. The outer periphery of the electrode rod 40 and the inner periphery of the water cooling jacket 44a are slidably in contact with each other so that water cooling can be performed.

On the other hand, on the left side of the furnace main body 1 in the drawing, an opening is provided by a freely openable and closable furnace lid 50, and the opening allows an object to be heated to be taken in and out. In addition, a furnace lid 50 is provided at the opening through a packing 10, and the furnace body 1 is sealed so as to be able to rotate relative to the furnace lid 50. An electrode sleeve 35 is attached to the center of the furnace lid 50, and a water-cooling jacket 44b constituting a cooling means is attached to an outer end (outside the furnace body 1) of the electrode sleeve 35. As a result, the consumption of the electrode rod 30 is reduced. The electrode rod 30 is inserted into the furnace through the water cooling jacket 44a and the electrode sleeve 45. The outer periphery of the electrode rod 30 and the water cooling jacket 44
The inner circumference of b is slidably contacted so that water cooling can be performed. The furnace lid 50 around the electrode sleeve 35 is provided with a gas supply port 59 constituting a supply means and an exhaust gas pipe 29 for discharging exhaust gas in the furnace. A gas pipe (not shown) is connected to the gas supply port 59, and the other end thereof is connected to a gas supply source. An inert gas or an oxidizing gas is supplied to the gas pipe at a necessary timing by switching means such as a valve. Through the supply port 59 and into the furnace. This gas supply source is used for recovering metallic aluminum from aluminum dross.
In order to reform the residual ash after the recovery of metallic aluminum into a high alumina raw material, an oxidizing gas such as air or oxygen is supplied. Note that a supply port for the inert gas and a supply port for the oxidizing gas may be separately provided.

An exhaust gas hood 28 is provided above the furnace main body 1. The aluminum dross treatment device removes harmful substances from exhaust gas discharged from the furnace main body 1 through an exhaust gas treatment device (not shown). , To be released to the atmosphere. Also, on the side of the furnace body 1,
A rotary cooler that constitutes a crushing means (not shown) is provided, and crushes or disintegrates the residual ash after collecting the metal aluminum to reduce the particle size of the residual ash. Thus, when the residual ash is reformed into a high alumina raw material, the reforming reaction is promoted.

The operation of the aluminum dross processing apparatus having the above configuration will be described. As shown in FIG. 1, while the electrode rods 30 and 40 inserted into the furnace are pulled out of the furnace, the carriage 51 is moved by the driving means to open the furnace lid 50. Next, after aluminum dross is put into the furnace main body 1 from the opening on the side of the furnace lid 50, the furnace lid 50 is closed by the furnace lid opening / closing means, and the tips of the electrode rods 30 and 40 are spaced apart by a predetermined distance. The electrode rods 30 and 40 are inserted into the furnace so as to face each other.

Next, while the furnace main body 1 is being rotated by the drive motor 19, the switching means of the gas supply means is operated, the supply port 59 is connected to the inert gas line, and the inert gas is supplied into the furnace. After the inside of the furnace is under an inert gas atmosphere, an arc is generated between the electrode rods 30 and 40 to heat the aluminum dross. In this heat treatment, the electrode rod 3
By heating the 0.40 while cooling it with a water cooling jacket, the consumption of the electrode rods 30 and 40 is reduced. In addition, in the method according to the present embodiment, the aluminum dross is uniformly heated by rotating the furnace main body 1. However, the aluminum dross may be rotated not only in one direction but also in a forward and reverse rotation. The heating process is continued as described above, and the heating process ends when a predetermined time has elapsed. When the heat treatment is completed, the metallic aluminum is recovered.

When the metal aluminum is recovered, the furnace lid 50 is opened again by the furnace lid opening / closing means 5, and then the furnace main body 1 is tilted by the tilting means 2 to discharge the residual ash of the metal aluminum to the outside of the furnace. When the residual ash is discharged out of the furnace, the residual ash is pulverized by a rotary cooler (not shown) so that the particle size of the residual ash becomes small. The pulverized residual ash is returned into the furnace, and the furnace body is heated by an arc while rotating the furnace body. After the temperature is raised to a temperature at which the reforming reaction proceeds (for example, 1000 ° C.), the gas supply source is switched. The reactor is connected to a reactive gas tank, an oxidizing gas as a reactive gas is supplied into the furnace, the furnace is kept in an acidic atmosphere, and the ash is reformed (heated) while the furnace body 1 is rotated. Do. In the heat treatment of the residual ash, as described above, the water cooling jackets 44a and 44a
The electrode rods 30 and 40 are heated while being cooled by 4b.
Thereby, the consumption of the electrode rods 30 and 40 can be significantly reduced, and the residual ash can be reformed into a high alumina raw material by oxidizing an aluminum compound such as aluminum nitride contained in the residual ash. . In the early stage of heating the pulverized residual ash, heating may be performed in an inert gas atmosphere in order to prevent the residual ash from adhering to the furnace chamber. Also, even when heating is not performed in an inert gas atmosphere, in order to minimize heat loss due to removal of exhaust gas, after raising the temperature to a temperature at which the reforming reaction proceeds, a reactive gas is supplied into the furnace, It is preferable to carry out the treatment of the residual ash.

[0026]

EXAMPLE 1 In the above-mentioned heat treatment for recovering metallic aluminum from aluminum dross, 500 kg of aluminum dross having an aluminum content of 60 wt% was charged into a furnace. Further, while rotating the furnace main body 1 at a furnace inner wall peripheral speed of 250 mm / sec, a heating treatment was performed for 30 minutes while maintaining the furnace temperature at 950 ° C. In addition, the incompatibility gas includes
Argon was used.

[0027]

Example 2 In the heat treatment for reforming the residual ash after the recovery of metallic aluminum into a high alumina raw material, the residual ash was crushed by a rotary cooler to a particle size of 2 mm or less. Further, while rotating the furnace main body 1 at a furnace inner wall peripheral speed of 250 mm / sec, a heating treatment was performed for 90 minutes while maintaining the furnace temperature at 1300 ° C. Further, the heating process was performed while supplying air as an oxidizing gas into the furnace during heating.

[0028]

[Table 1]

When metallic aluminum was recovered under the conditions of Example 1, as shown in Table 1, the water-cooled jacket 44a
・ 1.5kg / ton of electrode consumption compared to the case without 44b
To 0.9 kg / ton. Further, when the residual ash was heated under the conditions of Example 2, as shown in Table 1, the electrode consumption was reduced from 7.1 kg / ton to 2.5 kg / ton compared to the case where the water cooling jackets 44a and 44b were not provided. Could be reduced.

[0030]

According to the first aspect of the present invention, metallic aluminum is recovered from aluminum dross by using a rotary arc furnace that generates an arc between a pair of electrodes and heats while rotating around the electrodes. Later, the residual ash remaining in the rotary arc furnace, again using the rotary arc furnace, an aluminum dross processing apparatus for reforming into high alumina raw material, cooling means for cooling the electrode of the rotary arc furnace, Supply means for supplying an oxidizing gas into the rotary arc furnace so as to keep the inside of the rotary arc furnace under an acidic atmosphere; and By heating the ash,
The residual ash is reformed into a high alumina raw material. As a result, it is possible to greatly reduce the consumption of the electrode, and it is also possible to oxidize an aluminum compound such as aluminum nitride contained in the residual ash to thereby convert the residual ash into a high alumina raw material. .

According to a second aspect of the present invention, in addition to the configuration of the first aspect, the cooling means is a water-cooled jacket provided outside the electrode sleeve of the rotary arc furnace. Thereby, even in the event of a water leak, the cooling water does not enter the rotary arc furnace, so that an explosion accident can be prevented from occurring.

According to a third aspect of the present invention, in addition to the configuration of the first or second aspect, a discharging means for discharging the residual ash to the outside of the rotary arc furnace and a fine particle size of the residual ash are provided. Crushing means for crushing and crushing the residual ash, and returning the crushed residual ash to the rotary arc furnace and heating it again to convert the residual ash into a high alumina raw material. It is a composition to qualify. Thereby, since the reforming reaction from the residual ash to the high alumina raw material can be promoted, there is an effect that the reforming reaction time can be shortened.

According to a fourth aspect of the present invention, there is provided an aluminum dross for recovering metallic aluminum from aluminum dross by using a rotary arc furnace which generates an arc between a pair of electrodes and heats while rotating about the electrodes. A processing apparatus, comprising: a cooling unit that cools an electrode of the rotary arc furnace; and a supply unit that supplies an inert gas into the rotary arc furnace so as to keep the inside of the rotary arc furnace under an inert atmosphere. And heating the aluminum dross under an inert atmosphere while cooling the electrodes by the cooling means, thereby separating metallic aluminum. Thereby, the consumption of the electrodes can be reduced, and the loss due to the oxidation of the metal aluminum is eliminated, so that the recovery rate of the metal aluminum can be increased.

According to a fifth aspect of the present invention, after a metal aluminum is recovered from aluminum dross by using a rotary arc furnace that generates an arc between a pair of electrodes and heats while rotating around the electrodes, An aluminum dross processing method for modifying residual ash remaining in the rotary arc furnace into a high alumina raw material, wherein the rotary ash furnace is kept under an acidic atmosphere, and the residual ash is heated while cooling the electrodes. In this method, the residual ash is reformed into a high alumina raw material. As a result, it is possible to greatly reduce the consumption of the electrode, and it is also possible to oxidize an aluminum compound such as aluminum nitride contained in the residual ash to thereby convert the residual ash into a high alumina raw material. .

According to a sixth aspect of the present invention, in addition to the method of the fifth aspect, the residual ash is discharged out of the rotary arc furnace, crushed and crushed, and then the crushed and crushed residue is discharged. The method is a method of reforming the residual ash into a high alumina raw material by returning the ash into the rotary arc furnace and heating the ash. This allows
Since the reforming reaction from the residual ash to the high alumina raw material can be promoted, there is an effect that the reforming reaction time can be shortened.

According to a seventh aspect of the present invention, there is provided an aluminum dross for recovering metallic aluminum from aluminum dross by using a rotary arc furnace which generates an arc between a pair of electrodes and heats while rotating around the electrodes. A method of treating, wherein the aluminum dross is heated while the electrode is cooled while keeping the inside of the rotary arc furnace under an inert atmosphere, thereby separating metallic aluminum from the aluminum dross. Thereby, the consumption of the electrodes can be reduced, and the loss due to the oxidation of the metal aluminum is eliminated, so that the recovery rate of the metal aluminum can be increased.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an entire aluminum dross processing apparatus.

FIG. 2 is a diagram illustrating a tilting unit.

FIG. 3 is a diagram illustrating a furnace lid opening / closing unit.

FIG. 4 is a diagram illustrating a furnace main body.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Furnace main body 2 Tilting means 3.4 Electrode means 5 Furnace lid opening / closing means 11/12 Annular rail 13 Support base 14 Support shaft 15 Holding frame 30/40 Electrode rod 31/41 Electrode holder 50 Furnace lid 59 Gas supply port 44a Water cooling jacket (Cooling means) 44b Water cooling jacket (Cooling means)

 ──────────────────────────────────────────────────の Continuation of front page (72) Inventor Masahiro Tateno 1-3-1 Uchisaiwaicho, Chiyoda-ku, Tokyo Tokyo Electric Power Company

Claims (7)

[Claims] An arc is generated between a pair of electrodes, and a metal arc is recovered from aluminum dross by using a rotary arc furnace that heats while rotating around the electrodes. An aluminum dross processing apparatus for reforming remaining ash again into a high alumina raw material using the rotary arc furnace, wherein a cooling means for cooling an electrode of the rotary arc furnace; Supply means for supplying an oxidizing gas into the rotary arc furnace so as to keep the ash under an acidic atmosphere, by heating the residual ash under an acidic atmosphere while cooling the electrode by the cooling means. An aluminum dross processing apparatus, wherein the residual ash is reformed into a high alumina raw material. 2. The aluminum dross treatment apparatus according to claim 1, wherein said cooling means is a water-cooled jacket provided outside the electrode sleeve of said rotary arc furnace. 3. A discharge means for discharging the residual ash out of the rotary arc furnace, and crushing and / or crushing the residual ash so as to reduce the particle size of the residual ash.
And a crushing means for crushing, wherein the ash residue is returned to the rotary arc furnace and heated again to reform the ash residue into a high alumina raw material. Or the aluminum dross processing apparatus according to claim 2. 4. An aluminum dross processing apparatus for recovering metallic aluminum from aluminum dross using a rotary arc furnace that generates an arc between a pair of electrodes and heats while rotating around the electrodes, Cooling means for cooling the electrode of the rotary arc furnace; and supply means for supplying an inert gas into the rotary arc furnace so as to keep the inside of the rotary arc furnace under an inert atmosphere. An aluminum dross processing apparatus characterized in that the aluminum dross is heated under an inert atmosphere while cooling the electrode, thereby separating metallic aluminum. 5. A method of generating an arc between a pair of electrodes and recovering metallic aluminum from aluminum dross by using a rotary arc furnace that heats while rotating about the electrodes, and then places the aluminum in the rotary arc furnace. An aluminum dross treatment method for modifying the remaining ash into a high alumina raw material, comprising: maintaining the inside of the rotary arc furnace under an acidic atmosphere; heating the remaining ash while cooling the electrode; A method for treating aluminum dross, which comprises converting ash to a high alumina raw material. 6. The residual ash is discharged out of the rotary arc furnace, crushed and crushed, and the crushed and crushed residual ash is returned to the rotary arc furnace and heated, thereby obtaining the residual ash. 6. An aluminum dross treatment method according to claim 5, wherein said material is modified into a high alumina raw material. 7. An aluminum dross processing method for recovering metallic aluminum from aluminum dross using a rotary arc furnace that generates an arc between a pair of electrodes and heats while rotating around the electrodes, An aluminum dross processing method for separating metallic aluminum from the aluminum dross by keeping the inside of the rotary arc furnace under an inert atmosphere and heating the aluminum dross while cooling the electrodes.