KR101966206B1 - Aluminum melting furnace - Google Patents

Abstract

The present invention relates to an aluminum melting furnace, comprising: a heating chamber having a heating unit for heating an aluminum molten metal; A stirring unit for stirring the aluminum molten metal; and a control unit for controlling the flow of the aluminum molten metal flowing from the heating chamber and the flow of the molten aluminum formed by the stirring unit in advance And a first guide member for guiding the flow of the molten aluminum so as to be mixed in a predetermined mixed region.

Description

Aluminum melting furnace

The present invention relates to an aluminum melting furnace for melting aluminum scrap.

Many aluminum parts used in automobiles, household appliances and construction materials are manufactured using aluminum casting equipment. It is the aluminum melting furnace to supply the aluminum casting apparatus with the aluminum molten metal. Aluminum melting furnace is a device which dissolves aluminum scrap formed at a certain size into high heat.

A conventional aluminum melting furnace is provided with a greenhouse having a burner for heating molten aluminum, a molten metal stirring chamber having a molten metal pump for pumping molten aluminum discharged from the molten metal room, and an aluminum compression And includes a chamber for charging a chip chunk (Korean Registered Patent No. 10-1425572, published on July 31, 2014).

Here, the aluminum compression compacted chip is also called an aluminum ingot, and a large number of aluminum chips generated during the production or processing of aluminum products are compressed. By the way, the aluminum compacting chip lumps contain many voids in the process of compressing the aluminum chip. Therefore, in the conventional aluminum melting furnace, the heat is not sufficiently transferred to the center of the aluminum compression chunks put into the molten aluminum and the melting efficiency is lowered. The aluminum compacting chip is lifted up to the surface of the aluminum molten metal and brought into contact with the atmosphere, There is a problem.

In order to solve the above-mentioned problems, the conventional aluminum melting furnace is pumped in a molten metal stirring chamber and then injected into a molten aluminum which has been transferred to a molten aluminum chamber. In this case, however, due to the low specific gravity of the aluminum compacting chip, The lump of compressed chips is melted in the state of being suspended in the molten aluminum. Therefore, the conventional aluminum melting furnace still has a problem that the dissolution efficiency is lowered even when a mass of aluminum compressed chips is poured into the aluminum molten aluminum pumped in the molten metal stirring chamber, and the amount of aluminum oxide generated is large and the recovery rate of pure aluminum is lowered.

On the other hand, paints and other inclusions are generally included in the aluminum ingot which is put into the molten aluminum. As these inclusions increase, the purity of aluminum decreases. In order to solve the problems caused by such inclusions and the aforementioned aluminum oxide, a flux capable of preventing the oxidation of aluminum and capable of trapping inclusions is put into the molten aluminum. The dross generated by fluxing the molten aluminum in this way is called black dross.

However, when the aluminum melt is flux-treated, a large amount of aluminum is contained in the black dross during the formation of the black dross. Therefore, the conventional aluminum melting furnace still has a problem that the recovery rate of pure aluminum is lowered even when flux treatment is performed.

An object of the present invention is to provide an aluminum melting furnace improved in structure so as to increase the melting efficiency of aluminum scrap.

It is another object of the present invention to provide an aluminum melting furnace which is improved in structure so that a molten aluminum scrap and flux can be charged into an aluminum molten metal by using an agitating unit and a molten aluminum molten metal can be supplied to the aluminum molten metal .

Further, it is an object of the present invention to provide an aluminum melting furnace improved in structure so that molten aluminum can be smoothly circulated only by a fluid force provided from an agitating unit without assistance of a molten metal pump.

Further, it is an object of the present invention to provide an aluminum melting furnace improved in structure so as to reduce the amount of aluminum oxide generated.

Further, it is an object of the present invention to provide an aluminum melting furnace improved in structure so as to increase the recovery rate of pure aluminum.

In order to solve the above-described problems, an aluminum melting furnace according to a preferred embodiment of the present invention includes: a heating chamber having a heating unit for heating aluminum molten metal; A stirring unit for stirring the aluminum molten metal; and a control unit for controlling the flow of the aluminum molten metal flowing from the heating chamber and the flow of the molten aluminum formed by the stirring unit in advance And a first guide member for guiding the flow of the molten aluminum so as to be mixed in a predetermined mixed region.

Preferably, the first guide member has a first surface for guiding the flow of the molten aluminum introduced from the heating chamber toward the mixed region.

Preferably, the first guide member further includes a second surface for guiding the flow of the molten aluminum formed by the stirring unit to the mixing region.

Preferably, the first surface and the second surface are arranged so that the flow of the molten aluminum melted from the heating chamber and the flow of the molten aluminum formed by the stirring unit are mixed at an acute angle in the mixed region, .

Preferably, the apparatus further comprises a first flow passage communicating the heating chamber and the dissolution chamber so that the molten aluminum heated by the heating unit flows into the dissolution chamber from the heating chamber, And further includes a wall.

Preferably, the first guide member is disposed between the first flow passage and the agitation unit so as to partition between the first flow passage and the agitation unit.

Preferably, the first surface is formed by extending from the first flow passage toward the mixing region at a predetermined first point of the wall, such that the flow of the molten aluminum introduced from the heating chamber is directed toward the mixing region from the first flow passage And the second surface is formed so as to extend toward the mixing region at a predetermined second point of the wall so that the flow of the molten aluminum formed by the stirring unit is directed to the mixing region in the stirring unit.

Preferably, the first guide member is arranged so that the flow of the molten aluminum melt mixed in the mixed region passes through a space between the inner surface of one of the first guide member and the dissolution chamber, And are spaced apart from each other by a predetermined distance.

Preferably, the first guide member protrudes from the wall toward one of the inner side surfaces by a length of 0.25 times or more and 0.5 times or less of the distance between the first flow passage and the one inner side surface.

Preferably, the apparatus further comprises a second guide member for guiding the flow of the molten aluminum melt mixed in the mixed region so that the flow of the molten aluminum melt mixed in the mixed region is directed to the interstitial space.

Preferably, the second guide member has a curved surface or a polygonal surface eccentric to the interspace toward the one of the inner side surfaces from the first flow passage.

Preferably, the second surface extends toward one end of the curved surface or the polyhedral surface located on the side of the first flow passage.

Preferably, the second guide member is disposed at an edge portion connecting one of the inner side surfaces of the dissolution chamber and one of the inner side surfaces located between the one inner side surface and the wall.

Preferably, the curved surface has a radius of curvature corresponding to a distance between one end of the curved surface and the corner.

Preferably, the wall is provided with a first guide member and a second guide member which communicate with the melting chamber so as to allow the molten aluminum that has passed through the space between the first guide member and the one inner surface to flow into the heating chamber from the melting chamber. Further comprising a flow passage.

Preferably, the stirring unit is formed to be positioned between the first guide member and the second flow passage.

Preferably, the stirring unit has a stirring impeller installed at a predetermined depth of the aluminum molten metal.

Preferably, the stirring impeller includes a disk having a predetermined diameter and a plurality of planar blades radially disposed on the disk.

Preferably, the second flow passage is formed so as to be spaced apart from the predetermined third point of the wall in close proximity to the center axis of the stirring impeller by 1.5 times or more and 2.5 times or less of the diameter of the stirring impeller.

Preferably, the stirring impeller is rotated in a predetermined rotational direction so that the flow of the molten aluminum formed by the rotation of the stirring impeller is directed to the mixing region along the second surface.

Preferably, the second flow passage is formed at a position deeper than a surface of the molten aluminum by a predetermined depth.

Preferably, the second flow passage is formed so that the uppermost portion of the second flow passage is located at a depth of at least 0.5 times the level of the molten aluminum from the surface of the molten aluminum.

Preferably, the second flow passage has a cross-sectional area that is at least 1.5 times greater than the first flow passage.

Preferably, the melting chamber further comprises a flux supply unit for injecting flux into the molten aluminum.

Preferably, the stirring unit forms a vortex in the molten aluminum, and the raw material supplying unit injects the aluminum scrap into the vortex, and the flux supplying unit injects the flux into the vortex.

The aluminum melting furnace according to the present invention has the following effects.

First, the present invention can reduce the amount of aluminum oxide generated by rapidly charging aluminum scrap into a molten aluminum through a vortex.

Second, the present invention can minimize the flow loss of molten aluminum by adjusting the flow path of the molten aluminum through the guide member. Thus, according to the present invention, the molten aluminum can be smoothly circulated only by the fluid force provided from the stirring impeller without the necessity of separately installing the molten metal pump. Therefore, according to the present invention, it is possible to prevent the molten metal pump from being damaged by the refractory or other constituent pieces constituting the aluminum melting furnace, and the installation cost of the molten metal pump can be reduced.

Thirdly, according to the present invention, black dross formed by selectively capturing non-metallic inclusions (inclusion) is sphere-shaped through a vortex to form spherical black dross, whereby aluminum metal And the dissolution recovery rate of pure aluminum can be increased. Further, since the present invention does not require a separate dross reprocessing process for recovering aluminum contained in the dross, it is possible to reduce the cost of reprocessing the dross.

Fourthly, according to the present invention, it is possible to perform the melting operation of the aluminum scrap in a state in which the spherical black dross covers the molten aluminum in the melting chamber, so that the molten aluminum in the melting chamber is not covered with the spherical black dross, It is possible to increase the temperature of the molten aluminum because the heat insulating effect is superior to the case of performing the melting operation. Therefore, according to the present invention, the melting operation of the aluminum scrap can be performed in a state where the temperature of the molten aluminum is raised, so that the melting efficiency of the aluminum scrap can be improved.

1 is a plan view showing a schematic structure of an aluminum melting furnace according to a preferred embodiment of the present invention.
2 is a cross-sectional view of the dissolution chamber shown in Fig.
Fig. 3 is a view for explaining an aspect in which the flow of aluminum melt is controlled by the guide member shown in Fig. 1; Fig.
Fig. 4 is a perspective view of the stirring impeller shown in Fig. 2; Fig.
5 is a view for explaining a process of forming a spherical black dross in the dissolving chamber shown in Fig.
6 is an actual photograph of the spherical black dross shown in Fig. 5;
7 is a plan view of a melting chamber showing a state in which spherical black dross is floating on the surface of molten aluminum contained in the melting chamber shown in Fig.

Hereinafter, some embodiments of the present invention will be described in detail with reference to exemplary drawings. It should be noted that, in adding reference numerals to the constituent elements of the drawings, the same constituent elements are denoted by the same reference symbols as possible even if they are shown in different drawings. In the following description of the embodiments of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the difference that the embodiments of the present invention are not conclusive.

In describing the components of the embodiment of the present invention, terms such as first, second, A, B, (a), and (b) may be used. These terms are intended to distinguish the constituent elements from other constituent elements, and the terms do not limit the nature, order or order of the constituent elements. Also, unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the relevant art and are to be interpreted in an ideal or overly formal sense unless explicitly defined in the present application Do not.

Fig. 1 is a plan view showing a schematic structure of an aluminum melting furnace according to a preferred embodiment of the present invention, and Fig. 2 is a sectional view of the melting chamber shown in Fig.

1, an aluminum melting furnace 1 according to a preferred embodiment of the present invention includes a heating chamber 10 in which a molten aluminum melt M is heated and an aluminum scrap A and a flux F, And a dissolution chamber 20 to be introduced into the reaction chamber M and the like.

The aluminum melting furnace 1 has a plurality of inner spaces formed to be surrounded by a plurality of walls 30 having a refractory material. The heating chamber 10 and the dissolution chamber 20 are respectively provided in the inner space of one of the inner spaces of the aluminum melting furnace 1 independently of the other inner spaces. The shapes of the heating chamber 10 and the melting chamber 20 are not particularly limited. For example, the heating chamber 10 and the melting chamber 20 may each be provided in a square shape.

1, the wall 32 provided between the heating chamber 10 and the melting chamber 20 among the walls 30 of the aluminum melting furnace 1 is made of aluminum melt M, A first flow passage 32a communicating the heating chamber 10 and the dissolution chamber 20 so as to be able to flow into the dissolution chamber 20 from the heating chamber 10; And a second flow passage 32b communicating the heating chamber 10 and the dissolution chamber 20 so as to be able to flow into the heating chamber 10 from the heating chamber 10. The first flow passage 32a and the second flow passage 32b are preferably formed at a position deeper than a surface of the molten aluminum M by a predetermined depth. 2, the first flow passage 32a and the second flow passage 32b are connected to the wall 32 (see FIG. 2) so as to be connected to the deepest portion of the heating chamber 10 and the melting chamber 20, respectively , But it is not limited thereto. The molten aluminum M can sequentially circulate the heating chamber 10 and the melting chamber 20 through these flow passages 32a and 32b in a predetermined order. The details of the circulation of the molten aluminum M will be described later.

The heating chamber 10 is a space for heating the molten aluminum M to a predetermined temperature. The heating chamber 10 is communicated with the melting chamber 20 by the first flow passage 32a and the second flow passage 32b to transfer the molten aluminum M to the melting chamber 20, ).

The heating chamber 10 is formed with a sealing structure in which the remaining portions except the portion connected to the first flow passage 32a and the second flow passage 32b are shielded from the outside so that heat loss can be minimized.

1, the heating chamber 10 is provided with a heating unit 12 for heating the molten aluminum M contained in the heating chamber 10 and a molten aluminum melt M contained in the heating chamber 10, And an outflow port (14) for discharging to the outside of the aluminum melting furnace (1).

The heating unit 12 is a device for heating the molten aluminum M contained in the heating chamber 10 to a predetermined temperature. The structure of the heating unit 12 is not particularly limited. For example, as shown in Fig. 1, the heating unit 12 may be a burner installed in any one of the walls 30 provided so as to surround the heating chamber 10. As shown in Fig.

The temperature of the molten aluminum (M) contained in the heating chamber (10) can be measured by a temperature sensor (not shown) provided in the heating chamber (10). The heating unit 12 receives the temperature of the molten aluminum M contained in the heating chamber 10 from the temperature sensor and can heat the molten aluminum M contained in the heating chamber 10 to a predetermined heating temperature have.

The outflow port (14) provides an outlet for discharging the molten aluminum (M) contained in the heating chamber (10) to the outside of the aluminum melting furnace (1). The tapping tunnel 14 may be connected to an aluminum manufacturing apparatus for producing an aluminum casting or may be connected to a molten metal transfer vessel for transferring the molten aluminum (M). An open / close valve (18) capable of selectively opening and closing the tapping tunnel (14) can be installed in the tapping tunnel (14). The molten aluminum M contained in the heating chamber 10 can be introduced into the dissolution chamber 20 through the first flow passage 32a or discharged to the outside through the tapping tunnel 14. [

FIG. 3 is a view for explaining how the flow of molten aluminum is controlled by the guide member shown in FIG. 1, and FIG. 4 is a perspective view of the stirring impeller shown in FIG.

5 is a view for explaining a process of forming a spherical black dross in the dissolving chamber shown in FIG. 1, and FIG. 6 is an actual photograph of the spherical black dross shown in FIG.

The melting chamber 20 is a space for injecting the flux F and the aluminum scrap A into the molten aluminum M of aluminum. The dissolving chamber 20 communicates with the heating chamber 10 through the first flow passage 32a and the second flow passage 32b to receive the molten aluminum M from the heating chamber 10, ) Of the molten aluminum (M).

The melting chamber 20 is formed with an open structure in which at least a part of the upper surface is opened so as to allow the flux F and the aluminum scrap A to be introduced into the molten aluminum M contained in the melting chamber 20, (10). ≪ / RTI > That is, the dissolution chamber 20 is formed in an open structure so that the aluminum scrap A and the flux F can be injected into the molten aluminum M contained in the dissolution chamber 20 to perform a dissolving operation, The heating chamber 10 is formed to have a relatively small volume as compared with the heating chamber 10. The volume ratio of the heating chamber 10 and the dissolution chamber 20 is preferably about 3: 1, but is not limited thereto.

2 and 3, the melting chamber 20 is provided with a stirring unit 21 for stirring the molten aluminum M and a flux supply unit 21 for supplying the flux F to the molten aluminum M A raw material supply unit 23 for supplying the aluminum scrap A to the aluminum melt M and a flow M1 of molten aluminum M flowing from the heating chamber 10 and a stirring unit 21, And a guide member 24 for guiding the flow of the molten aluminum M so that the flow M2 of the molten aluminum M formed by the molten aluminum M does not interfere with each other.

The stirring unit 21 is a member for stirring the molten aluminum (M). 2, the stirring unit 21 includes a driving motor 21a for providing a driving force and a stirring impeller 21b for stirring the molten aluminum M through a driving force provided from the driving motor 21a .

As shown in FIG. 2, the drive motor 21a is preferably installed outside the melting chamber 20 so as not to be immersed in the molten aluminum M, but is not limited thereto. This drive motor 21a can provide a driving force for stirring the aluminum melt M to the stirring impeller 21b.

3, the drive motor 21a is configured so that the flow M2 of the molten aluminum M formed by the stirring impeller 21b is transmitted to the second surface 25b of the first guide member 25 The stirring impeller 21b can be rotationally driven in a predetermined rotational direction so as to be directed to the predetermined mixing region B of the melting chamber 20 along the predetermined direction. The rotational direction of the stirring impeller 21b is not particularly limited and the driving motor 21a may rotate the stirring impeller 21b clockwise or counterclockwise according to the positional relationship between the stirring impeller 21b and the first flow passage 32a As shown in Fig.

The stirring impeller 21b is installed at a predetermined depth of the molten aluminum M so as to be immersed in the molten aluminum M as shown in Fig. Further, the stirring impeller 21b is installed so as to be positioned between the first guide member 25 and the second flow passage 32b, as shown in Fig. The structure of the stirring impeller 21b is not particularly limited. For example, the stirring impeller 21b may include a disk 21c to be axially coupled to the driving motor 21a, wings 21d to be coupled to the disk 21c, and the like .

As shown in Fig. 4, the disk 21c has a predetermined diameter and is axially coupled to the drive motor 21a by a rotation shaft 21e. The disk 21c preferably has a disk shape, but is not limited thereto. The rotating shaft 21e is a member for transmitting the driving force of the driving motor 21a to the disk 21c and the lower end of the rotating shaft 21e is immersed in the molten aluminum M to be axially engaged with the central axis of the disk 21c , And the upper end of the rotating shaft 21e extends to the outside of the melting chamber 20 and is axially coupled to the driving motor 21a.

The wings 21d have a flat plate-like structure as shown in Fig. 4, and are radially arranged on the disk 21c at predetermined intervals. The wings 21d are preferably arranged to be perpendicular to the disc 21c, but are not limited thereto. The wings 21d are preferably connected at one end to the rotary shaft 21e, but the present invention is not limited thereto.

The size of the stirring impeller 21b is not particularly limited. For example, as shown in Fig. 3, the stirring impeller 21b may have a diameter D of 0.2 times or more and 0.5 times or less of the width W of the melting chamber 20. Here, the width W of the dissolution chamber 20 is defined by the wall 32 on which the flow passages 32a and 32b are formed and the flow passages 32a and 32b among the walls 30 provided so as to surround the dissolution chamber 20, And 32b, respectively.

As shown in Figs. 2 and 3, the stirring impeller 21b is provided with a vortex V, which is swirled down around the stirring impeller 21b, in the molten aluminum M, and the vortex V ) Of the molten aluminum (M) facing the tangential direction of the molten aluminum (M).

When the stirring impeller 21b directly faces the flow M1 of the molten aluminum M flowing from the heating chamber 10 through the first flow passage 32a, the stirring impeller 21b is rotated by the stirring impeller 21b There is a fear that the flow M2 of the formed molten aluminum M and the flow M1 of the molten aluminum M flowing from the heating chamber 10 through the first flow path 32a cancel each other. 3, the stirring impeller 21b does not directly face the flow of the molten aluminum M from the heating chamber 10 through the first flow passage 32a, And is spaced apart from the first flow passage 32a by a predetermined gap. The flow of the molten aluminum M flowing from the heating chamber 10 through the first flow passage 32a is referred to as a first flow M1 and the flow of the molten aluminum M through the tangential direction The flow of the molten aluminum M formed by the stirring impeller 21b is referred to as a second flow M2.

The flux supply unit 22 is a device for inputting the flux F supplied from an external flux supply source (not shown) into the molten aluminum M contained in the dissolution chamber 20. The flux F is a mixed salt having a specific gravity smaller than that of aluminum and is formed of a material having a high affinity with the nonmetallic inclusion of the aluminum scrap (A).

The flux supply unit 22 injects the flux F into the eddy current V generated by the stirring unit 21, as shown in Fig. Then, the flux F can be rapidly charged into the aluminum molten metal M by the vortex V and then diffused evenly into the molten aluminum M after being dissolved. However, the present invention is not limited to this, and the flux supply unit 22 may inject the flux F to other portions of the molten aluminum M than the vortex V.

The injection timing of the flux (F) is not particularly limited. For example, the flux supply unit 22 may preliminarily inject the flux F into the eddy current V before the raw material supply unit 23 puts the aluminum scrap A into the eddy current V. Then, the flux F is immersed and dissolved in the molten aluminum M while swirling downward by the eddy current (V). Since the flux F has a specific gravity relatively smaller than that of aluminum, the flux F dissolved in the molten aluminum M floats on the surface of the molten aluminum M and melts on the surface of the molten aluminum M Forming a flux layer, i.e., a salt layer. Such a molten flux layer can prevent the aluminum scrap A, which has been introduced into the molten aluminum (M) and the molten aluminum (M), from being in contact with oxygen in the atmosphere, thereby reducing the amount of aluminum oxide produced.

Such flux (F) has a composition capable of selectively capturing inclusions and forming a molten flux layer on the surface of the molten aluminum (M). Preferably, the flux (F) may comprise 93-97 parts by weight of a mixture of sodium chloride (NaCl) and potassium chloride (KCl) in the same weight parts and 3-7 parts by weight of cryolite (Potassium Cryolite). More preferably, flux (F) may comprise 47.5 parts by weight of sodium chloride (NaCl), 47.5 parts by weight of potassium chloride (KCl) and 5 parts by weight of potassium aluminum fluoride (KAlF4). On the other hand, when the supply of the aluminum scrap A is started by the raw material supply unit 23, the flux supply unit 22 starts to supply the flux F to the vortex V simultaneously with or at the same time as the closing timing of the aluminum scrap A, . That is, even after the start of feeding of the aluminum scrap A, the flux F is supplied continuously or intermittently in accordance with the supply trend of the aluminum scrap A.

The flux F is preferably supplied in an amount equal to the amount of the nonmetallic inclusion to be captured, but is not limited thereto. That is, the supply amount of the flux F can be adjusted according to the supply amount of the aluminum scrap A and the kind of the aluminum scrap A. For example, when aluminum scrap A containing a paint or other large amount of nonmetallic inclusions such as UBCs scrap is supplied, the supply amount of flux F is increased and the amount of aluminum scrap A having high purity is increased, The supply amount of the flux F can be reduced.

The raw material supply unit 23 is an apparatus for supplying the aluminum scrap A supplied from an external raw material supply source (not shown) to the molten aluminum M contained in the dissolution chamber 20.

The raw material supply unit 23 injects the aluminum scrap A into the vortex V generated by the stirring unit 21, as shown in Fig. Since the aluminum scrap A can be rapidly charged and melted into the molten aluminum M while swirling downward by the vortex V, the contact between the aluminum scrap A loaded in the molten aluminum M and the atmosphere is further enhanced The amount of generated aluminum oxide can be further reduced.

The timing of introduction of the aluminum scrap A is not particularly limited. For example, the raw material supply unit 23 can start supplying the aluminum scrap A after the molten flux layer is formed on the surface of the molten aluminum (M). Then, the aluminum scrap (A) can be charged into the molten aluminum (M) in a state where the molten flux layer is formed on the surface of the molten aluminum (M). As a result, the contact between the aluminum scrap A loaded in the molten aluminum M and the atmosphere is more effectively blocked, so that the amount of aluminum oxide generated can be further reduced.

When the diameter of the aluminum scrap A is large, there is a problem that the heat transmission rate is lowered. Therefore, it is preferable that the aluminum scrap (A) is at least a part of an aluminum chip having a diameter of 5 cm or less. When the diameter of the aluminum scrap (A) is large, the heat transmission rate is lowered, so that the aluminum chip having a relatively small diameter is supplied. Such an aluminum chip can be produced, for example, by shredding or processing aluminum scraps such as aluminum compacts.

The kind of the aluminum scrap A is not particularly limited. For example, the aluminum scrap A may be an aluminum waste scrap (UBCs, A 3XXX series, A 5XXXX series), at least a part of which mainly comprises aluminum, magnesium and aluminum alloys. The chemical composition of such aluminum waste can scrap is shown in Table 1 below.

part
Al alloy
line Chemical Composition (%) Si Fe Cu Mn Zn Mg Body A 3004 <0.3 <0.70 <0.25 1.0 - 1.5 <0.25 0.8 - 1.3 Lid A 5052 <0.25 <0.40 <0.10 <0.10 <0.10 2.2 - 2.8 Tab A 5182 <0.2 <0.35 <0.15 0.2 - 0.5 <0.25 4.0 - 5.0

On the other hand, the inclusions of the aluminum scrap (A) have a property that when the aluminum scrap (A) is charged into the molten aluminum (M) and melted, it coalesces with molten aluminum. Meanwhile, the soluble flux layer, that is, the flux (F) weakens the cohesive force between the inclusions and the molten aluminum to dissociate the inclusions and the molten aluminum, and selectively captures the molten aluminum and the dissociated inclusions to form the black dross . The black dross B1 increases in volume during the above-described forming process and has a lower specific gravity than that of the molten aluminum, thereby floating on the surface of the molten aluminum (M).

2, the black dross B1 is detached from the vortex V when it is lowered by the vortex V and reaches the lower end of the vortex V, and then the molten aluminum M) and joined to the vortex (V) by the suction force of the vortex (V) again. Thus, the black dross B1 is bonded to another black dross B1 generated on the surface of the molten aluminum M through this process. When this process is repeated, as shown in FIGS. 5 and 6, a spherical black dross B2 is formed in which a plurality of black dots B1 are spherically gathered. That is, the stirring unit 21 repeatedly descends and floats the black dross B1 through the vortex V, whereby a large number of black drosses B1 form spherical black dross B2 gathered in a spherical shape Lt; / RTI &gt;

The chemical composition of such spherical black dross (B2) is not particularly limited. For example, as described above, the aluminum scrap (A) is an aluminum waste can scrap (UBCs scrap) and the flux F is 47.5 parts by weight of sodium chloride (NaCl), 47.5 parts by weight of potassium chloride (KCl) (KAlF 4), the chemical composition of the spherical black dross (B2) is shown in Table 2 below.

Composition chemicals Chemical Composition (%) Al 5-10 Al ₂ O ₃ 25-35 Mg 5-10 MgO 5-10 NaCl 20-30 KCl 20-30

The spherical black dross B2 is formed gradually as the black dross B1 repeatedly descends and floats the aluminum molten metal M and thus the spherical black dross B2 is more uniform than the ordinary black dross formed once, The removal performance of nonmetallic inclusions is excellent. Therefore, when the spherical black droplet B2 is formed, the aluminum content of the droplet can be reduced as compared with the case of forming a general black droplet. That is, a black dross formed by fluxing white dross in a conventional black dross melting process, for example, a conventional aluminum waste cans melting process, has an aluminum content of about 50% or more, while the spherical black dross B2 has a black dross of about 10% Aluminum. Therefore, by forming the spherical black dross B2, the solubility recovery ratio of pure aluminum can be improved. Further, by forming the spherical black dross B2, the dross reprocessing process for recovering the aluminum trapped in the dross can be omitted by reprocessing the dross using the heat generating agent flux and the presser, The cost can be reduced.

The guide member 24 is a member for adjusting the paths of the first flow M1 and the second flow M2 so that the first flow M1 and the second flow M2 do not cancel each other.

The structure of the guide member 24 is not particularly limited. For example, the guide member 24 may include a first guide member 25 (see FIG. 1) provided so as to guide the first flow M1 and the second flow M2 toward the predetermined mixing region B of the melting chamber 20 ) And a second flow (M2) mixed with each other in the mixing region (B) by the first guide member (25) to the second flow passage (32b) And a guide member 26 may be provided. Here, the mixed region B refers to one region of the melting chamber 20 that is set at a position where the first flow M1 and the second flow M2 can be mixed to form an acute angle with each other. For convenience of explanation, the first flow (M1) and the second flow (M2) of the molten aluminum melt (M) mixed in the mixed region (B) by the first guide member 3 flow (M3).

The first guide member 25 has a block shape and includes a first flow M1 and a second flow M2 such that the first flow M1 and the second flow M2 are directed toward the mixing region B, As shown in FIG. For example, the first guide member 25 may include a first surface 25a provided on one side to guide the first flow M1 toward the mixing region B, B) and a second surface 25b provided on the other side so as to guide the first surface 25a and the second surface 25b.

The first guide member 25 is made of a refractory material and can be disposed between the first flow passage 32a and the stirring impeller 21b so as to partition the first flow passage 32a and the stirring impeller 21b have. The first guide member 25 is preferably formed separately and coupled to the wall 32, but is not limited thereto. That is, the first guide member 25 may be formed together with the wall body 32 so as to be integral with the wall body 32.

As shown in Fig. 3, the first guide member 25 is provided so as to extend from the wall body 32 to one side of the melting chamber 20 by a distance L1 smaller than the width W of the melting chamber 20. [ And can protrude toward the inner side surface 34a. One of the inner side surfaces 34a of the dissolution chamber 20 is an inner side of the wall 34 positioned to face the first flow passage 32a among the walls 30 provided to surround the dissolution chamber 20. [ Speak side. For convenience of explanation, the inner surface 34a of one of the dissolution chambers 20 will be referred to as a first inner surface 34a hereinafter.

For example, the first guide member 25 may extend from the wall body 32 toward the first inner side face 34a by a distance L1 of not less than 0.25 times and not more than 0.5 times the width W of the dissolution chamber 20 Can be protruded. 3, the first flow M1 is mixed with the second flow M2 in the mixing region B and then the first flow member M1 is mixed with the first flow guide member 25 and the first inner side surface 34a, Can pass through the space S and can be directed toward the second flow passage 32b.

The first surface 25a extends from the predetermined first point 32c of the wall 32 toward the mixed region B as shown in Fig. The first point 32c of the wall 32 is located between the inner surface 36a of the dissolving chamber 20 located between the wall 32 and the first inner surface 34a and the first surface 25a May be set at a position spaced apart from the other inner surface 36a of the dissolving chamber 20 by a predetermined gap so that the first flow M1 can pass through the space S. [ The other inner side surface 36a of the dissolution chamber 20 is a surface of the wall 36 disposed between the wall body 32 and the wall 34 among the walls 30 provided to surround the dissolution chamber 20. [ I say my side. For convenience of explanation, the other inner surface 36a of the dissolving chamber 20 will be referred to as a second inner surface 36a hereinafter.

The first surface 25a is preferably parallel to the second inner surface 36a, but is not limited thereto. 3, the first flow M1 flows into the melting chamber 20 through the first flow passage 32a and then flows into the first face 25a through the first flow passage 32a, To the mixed region (B). The first surface 25a can prevent the first flow M1 from flowing directly toward the stirring impeller 21b and thereby canceling out the first flow M1 and the second flow M2 from each other.

The second surface 25b extends from the second predetermined point 32d of the wall 32 toward the mixed region B as shown in Fig. The second point 32d of the wall 32 may be set at a position spaced from the first point 32c by a predetermined distance so as to be located on the side of the second flow passage 32b with respect to the first point 32c . The second surface 25b may be formed at a predetermined angle with the first surface 25a. For example, the second surface 25b may be formed such that a hypothetical line E extending from the second surface 25b is formed at a predetermined intersection point 36b of the second inner surface 36a, And may be formed to have an acute angle with the first surface 25a. Here, the imaginary line E refers to an imaginary line extending from the second surface 25b so as to be in line with the second surface 25b. According to this second surface 25b, as shown in Fig. 3, a part of the second flow M2 formed by the stirring impeller 21b and directed toward the first flow path 32a, The second layer M2 may be mixed at an acute angle with the first flow M1 guided toward the mixing region B by the first surface 25a by being guided toward the mixing region B by the second surface 25b . The second surface 25b thus minimizes the mixing angle of the first flow M1 and the second flow M2 thereby preventing the first flow M1 and the second flow M2 from offsetting each other .

As described above, the first surface 25a and the second surface 25b are formed so that the first flow M1 and the second flow M2 are mixed at an acute angle in the mixing region B, The flow of the flow M2 can be adjusted individually. Accordingly, the first guide member 25 can minimize the flow loss of the molten aluminum M generated when the first flow M1 and the second flow M2 are mixed.

The second guide member 26 has a block shape and has a third flow M3 such that the third flow M3 is directed toward the space S between the first guide member 25 and the first inner side surface 34a. As shown in FIG. The second guide member 26 is moved toward the space S between the first guide member 25 and the first inner side surface 34a toward the first inner side surface 34a from the first flow path 32a side And may have a curved surface 26a provided eccentrically on one side. The second guide member 26 may be formed in a curved shape so that the first guide member 25 and the second guide member 25 can be moved in the direction from the first flow passage 32a toward the first inner side 34a, And may have a polygonal surface eccentrically provided on one side toward the space S between the inner side surfaces 34a. For convenience of explanation, the present invention will be described below by taking the case where the second guide member 26 has a curved surface 26a as an example.

The second guide member 26 is formed of a refractory material and may be disposed at a corner where the first inner side 34a and the second inner side 36a are connected. The second guide member 26 is preferably formed with the walls 34 and 36 integrally with the walls 34 and 36, but is not limited thereto. That is, the second guide member 26 may be formed separately and may be coupled to the corner portion.

The curved surface 26a may extend from the intersection point 36b of the virtual line E and the second inner side surface 36a to the predetermined end point 34b of the first inner side surface 34a. The second surface 25b is directed toward one end of the curved surface 26a located at the intersection point 36b of the second inner surface 36a to naturally guide the second flow M2 toward the curved surface 26a have. The curvature radius R of the curved surface 26a is preferably equal to the distance L2 between the intersection point 36b of the second inner side surface 36a and the corner portion as shown in the following Equation 1, It is not.

This curved surface 26a gradually changes the path of the third flow M3 toward the space S between the first guide member 25 and the first inner side surface 34a as shown in Fig. . Thus, the second guide member 26 can minimize the loss of fluidity of the molten aluminum M generated during the path of the third flow M3. The third flow M3 whose path is switched by the curved surface 26a passes through the space S between the first guide member 25 and the first inner side surface 34a and then flows through the stirring impeller 21b (M2) mixed with the first flow (M1) in the mixed region (B) of the second flow (M2) formed by the second flow passage (32b) 10).

As described above, the first guide member 25 and the second guide member 26 can be formed at the time of mixing the first flow M1 and the second flow M2 and at the time of switching the third flow M3, The loss of fluidity of the molten aluminum (M) can be minimized. As a result, the aluminum melting furnace 1 does not need to separately provide a molten metal pump capable of additionally providing the molten aluminum to the molten aluminum melt M, and the molten aluminum molten metal M is heated only by the molten metal provided by the stirring impeller 21b, (10) and the dissolution chamber (20). Therefore, it is possible to prevent the molten metal pump from being damaged by the refining of the refractory or other constituent constituting the aluminum melting furnace 1, the aluminum melting furnace 1, and the installation cost of the molten metal pump can be reduced.

On the other hand, as described above, the black dross B1 and the spherical black dross B2 are repeatedly lowered and floated by the vortex (V). Therefore, the black dross B1 and the spherical black dross B2 may flow into the heating chamber 10 through the second flow passage 32b during the lifting process.

In order to solve this problem, the second flow passage 32b is formed by the stirring impeller 21b and the aluminum melt (not shown) so that the black dross B1 and the spherical black dross B2 do not reach the second flow passage 32b M, respectively, by a predetermined distance.

3, the second flow passage 32b extends from a predetermined third point 32e of the wall 32 located closest to the central axis of the stirring impeller 21b to the stirring impeller (not shown) 21b by a distance L3 of 1.5 times or more and 2.5 times or less of the diameter D of the electrodes 21a, 21b.

For example, as shown in Fig. 2, the second flow passage 32b is formed so that the uppermost portion of the second flow passage 32b is at least 0.5 times the liquid level of the molten aluminum M from the surface of the molten aluminum M May be formed to be located as deep as the distance L4.

The black dross B1 and the spherical black dross B2 can not reach the second flow passage 32b so that the black dross B1 and the spherical black dross B2 can not reach the second flow path 32b, It is possible to prevent the loss B2 from flowing into the heating chamber 10 through the second flow passage 32b.

On the other hand, in the melting chamber 20, the aluminum scrap A is dissolved in the molten aluminum M so that the molten aluminum M is newly produced. The flow rate of the molten aluminum M flowing from the melting chamber 20 into the heating chamber 10 through the second flow passage 32b is dissolved from the heating chamber 10 through the first flow passage 32a Is larger than the flow rate of the molten aluminum (M) flowing into the chamber (20). 2, in order to reduce the flow path resistance of the molten aluminum M in the second flow path 32b, the second flow path 32b is formed so as to be relatively in contact with the first flow path 32a It is preferable to have a wide cross-sectional area. For example, the second flow passage 32b may have a cross-sectional area that is at least 1.5 times greater than that of the first flow passage 32a.

7 is a plan view of a melting chamber showing a state in which spherical black dross is suspended on the surface of molten aluminum contained in the melting chamber of Fig.

When a large number of spherical black dross B2 is densely packed in the vortex V, the falling and floating action of the spherical black dross B2 by the vortex V is weakened and the efficiency of forming the spherical black dross B2 May be reduced. Therefore, it is preferable that the spherical black dross B2 grown by a predetermined reference diameter is separated from the vortex V to adjust the density of the spherical black dross B2 located at the vortex V to an appropriate level.

The reference diameter of the spherical black dross B2 is not particularly limited. For example, aluminum scrap (A) is an aluminum waste can scrap (UBCs scrap) and flux (F) is 47.5 parts by weight of sodium chloride (NaCl), 47.5 parts by weight of potassium chloride (KCl) and potassium aluminum fluoride , The reference diameter of the spherical black dross B2 is 2 cm to 5 cm.

The dissolution chamber 20 is provided with a separation unit 27 for separating the spherical black dross B2 from the vortex V in order to separate the spherical black dross B2 grown by the reference diameter from the vortex V, As shown in FIG.

2, the separating unit 27 includes a separating plate (not shown) having a shape capable of pulling a spherical black droplet B2 floating on the surface of the molten aluminum M toward the side away from the vortex V And a connecting rod 27b for connecting the separating plate 27a with a driving device (not shown) for moving the separating plate 27a. Here, the driving device is preferably a working equipment provided outside the melting chamber 20, but is not limited thereto.

As the separation unit 27 is provided as described above, the spherical black dross B2 larger than the predetermined reference value can be pulled away from the vortex V using the separation plate 27a to be separated from the vortex V have. Therefore, the separation unit 27 can prevent the formation efficiency of the spherical black droplets B2 from being lowered due to the dense spherical black droplets B2. However, the present invention is not limited to this. The separation unit 27 may be configured to push the spherical black dross B2 separated from the vortex V into the vortex V in a state where it is not grown by the reference diameter, When the amount of the spherical black dross B2 contained in the black dross B2 is equal to or higher than the appropriate level, the function of discharging the spherical black dross B2 to the outside can also be performed.

On the other hand, when the spherical black dross B2 is pulled away from the vortex V using the separation unit 27, the surface of the aluminum melt M is separated from the vortex V And is covered with the separated spherical black dross B2. Therefore, the molten aluminum melt M contained in the melting chamber 20 is shielded from the atmosphere by the spherical black droplets B2 covering the surfaces thereof, and the spherical black droplets B2 are melted in the melting chamber 20 having the open structure, And has a warming effect for the molten aluminum (M) contained in the molten aluminum (M). Therefore, compared to the case where the molten aluminum melt M is not covered by the spherical black loss B2, the heat loss of the molten aluminum M is minimized by the spherical black dross B2, The temperature is raised.

The conventional aluminum melting furnace generally has an aluminum melting furnace accommodated in the melting chamber at a temperature of about 700 ° C or lower and a temperature of the aluminum molten alloy M contained in the melting chamber 20 is raised to about 730 ° C or higher . As a result, the aluminum melting furnace 1 can further improve the melting efficiency of the aluminum scrap (A) as compared with the conventional aluminum melting furnace.

The foregoing description is merely illustrative of the technical idea of the present invention, and various changes and modifications may be made by those skilled in the art without departing from the essential characteristics of the present invention.

Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the scope of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The scope of protection of the present invention should be construed according to the following claims, and all technical ideas within the scope of equivalents should be construed as falling within the scope of the present invention.

1: Aluminum melting furnace
10: heating chamber
12: Heating unit
14: Outpost
16: opening / closing valve
20: Fusion room
21: stirring unit
21a: drive motor
21b: stirring impeller
21c: disk
21d: wings
21e:
22: flux supply unit
23: Raw material supply unit
24: guide member
25: first guide member
25a: first side
25b: second side
26: second guide member
26a:
27: Separation unit
27a: separator plate
27b: connecting rod
30: Wall
32: Wall
32a: a first flow passage
32b: a second flow passage
32c: First point
32d: second point
32e: Third point
34: Wall
34a: first inner side
34b: end point
36: Wall
36a: second inner side
36b: intersection
B: mixed region
F: Flux
A: Aluminum scrap
B1: Black Death
B2: Old Black Death
V: Vortex
M: Molten aluminum
M1: first flow
M2: second flow
M3: Third flow
E: virtual line

Claims (25)

A heating chamber having a heating unit for heating the molten aluminum;
An agitating impeller for agitating the molten aluminum to form a vortex in the molten aluminum and providing a flow force to the molten aluminum; a raw material supplying unit for injecting aluminum scrap into the vortex; A flux supply unit, and a guide member for guiding the flow of the molten aluminum; And
And a first flow passage communicating the heating chamber and the dissolution chamber so that the molten aluminum heated by the heating unit flows into the dissolution chamber from the heating chamber and includes a wall separating the heating chamber and the dissolution chamber and,
The flux supply unit may be configured such that before the raw material supply unit injects the aluminum scrap into the vortex, the flux is previously introduced into the vortex to form a molten flux layer on the surface of the molten metal,
Wherein the raw material supplying unit is configured to inject the aluminum scrap into the vortex so as to pass through the molten flux layer after the molten flux layer is formed,
The guide member
Wherein the first flow is a flow of the aluminum molten metal flowing from the heating chamber through the first flow passage and the second flow is a flow of the aluminum molten metal radiating around the stirring impeller by the flow force, And a first guide member for selectively guiding the first flow and the second flow to the predetermined mixed region of the first flow and the second flow selectively in the mixed region. The method according to claim 1,
Wherein the first guide member has a first surface for guiding the flow of the first flow toward the mixing region and guiding the first flow to the mixing region. 3. The method of claim 2,
Wherein the first guide member is configured to guide a portion of the second flow of the second flow toward the first flow passage toward the mixing region and guide the part of the second flow to the mixing region, And a second surface on which an aluminum alloy is formed. The method of claim 3,
Wherein the first surface and the second surface are formed to have a predetermined angle so that the first flow and the second flow of the portion are mixed at an acute angle in the mixing region. delete The method of claim 3,
Wherein the first guide member is disposed between the first flow passage and the stirring impeller so as to partition between the first flow passage and the stirring impeller. The method of claim 3,
The first surface extending from the predetermined first point of the wall toward the mixing region such that the first flow is directed from the first flow passage to the mixing region along the first surface,
Characterized in that the second face is formed to extend from the predetermined second point of the wall toward the mixing zone so that the second flow of the part is directed to the mixing zone from the stirring impeller along the second face Aluminum melting furnace. The method of claim 3,
Wherein the first guide member is configured such that a third flow, which is a flow of the molten aluminum formed by mixing the first flow and the second flow of the portion in the mixing region, is formed in one of the first guide member and the dissolution chamber And is spaced apart from the one inner side surface by a predetermined distance so as to pass through the space between the side surfaces. 9. The method of claim 8,
Wherein the first guide member is protruded from the wall toward one of the inner side faces by a length of 0.25 times or more and 0.5 times or less of a distance between the first flow passage and the one inner side face. . 9. The method of claim 8,
The guide member
Further comprising a second guide member for guiding the third flow so that a traveling path of the third flow is switched to the interspace. 11. The method of claim 10,
Wherein the second guide member has a curved surface or a polygonal surface eccentric to the interspace toward the one inner side surface from the first flow path side. 12. The method of claim 11,
And the second surface extends toward one end of the curved surface or the polygonal surface located on the side of the first flow passage. 13. The method of claim 12,
Wherein the second guide member is disposed on an inner side surface of the other one of the fusion chambers located between the one inner side surface and the wall and an edge portion connecting the one inner side surface. . 14. The method of claim 13,
Wherein the curved surface has a radius of curvature corresponding to a distance between one end of the curved surface and the corner portion. 9. The method of claim 8,
Wherein the wall is provided with a second flow passage communicating with the heating chamber and the dissolution chamber so that the molten aluminum which has passed through the space between the first guide member and the one inner side surface is introduced into the heating chamber from the dissolution chamber And an aluminum melting furnace. 16. The method of claim 15,
Wherein the stirring impeller is formed to be positioned between the first guide member and the second flow passage. 17. The method of claim 16,
Wherein the stirring impeller is installed at a predetermined depth of the aluminum molten metal. The method according to claim 1,
Wherein the stirring impeller includes a disk having a predetermined diameter and a plurality of flat blade blades radially disposed on the disk. 18. The method of claim 17,
Wherein the second flow passage is formed to be spaced apart from the third predetermined point of the wall that is closest to the center axis of the stirring impeller by 1.5 times or more and 2.5 times or less of the diameter of the stirring impeller. The method of claim 3,
Wherein the stirring impeller is rotated in a predetermined rotational direction so that the second flow of the part is directed to the mixing region along the second surface. 16. The method of claim 15,
Wherein the second flow passage is formed at a position deeper than a surface of the molten aluminum by a predetermined depth. 22. The method of claim 21,
And the second flow passage is formed such that the uppermost portion of the second flow passage is located deeply at a distance of 0.5 times or more the surface level of the molten aluminum from the surface of the molten aluminum. 16. The method of claim 15,
Wherein the second flow passage has a cross-sectional area that is at least 1.5 times greater than that of the first flow passage. delete delete

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