RU2233344C1 - Apparatus for electromagnetic refining of aluminum and its alloys - Google Patents

Abstract

FIELD: non-ferrous metallurgy, namely production of aluminum and its alloys, possibly removing from aluminum alloys alkali metal impurities, non-metallic and gaseous inclusions.

SUBSTANCE: apparatus includes lined vessel, lined metallic cover, gas distributing mechanism, mechanism for removing gas and device for creating rotation motion of melt in the form of multi-phase traveling electromagnetic field inductor. Lined metallic cover is made of high resistance non-magnetic steel.

EFFECT: enhanced manufacturing parameters due to contact-free agitation of melt.

4 cl, 4 dwg

Description

The invention relates to the field of non-ferrous metallurgy, in particular to the production of aluminum and its alloys, and can be used for refining aluminum alloys from impurities of alkali metals, non-metallic and gas inclusions.

A device for treating a melt with a reagent (a.s. No. 1532590, MKl. C 21 C 1/00, 1989) is known, containing a lined tank and a mechanical stirrer.

The disadvantage of this device is the complex design of the mechanical stirrer and the absence of a mechanism for venting gases, which does not allow the output to be highly purified from impurities melt.

Closest to the claimed device is a device for refining aluminum and alloys based on it (Description of a device for purifying aluminum from rare earth metals, the company "STAS Societe des technologies de L'Aluminium", 1846 Outarde Chicoutimi (Quebec) Canada G7K1H1), containing a lined container for transporting the melt, a lined metal cover, a gas distribution mechanism, a gas removal mechanism and a device for creating a rotational movement of the melt.

The main disadvantages of such a device are:

1. Direct contact of the mechanical rotor with a high-temperature melt, which leads to its rapid wear.

2. The presence of moving mechanical parts in the rotor drive, requiring additional protection systems from high temperature and aggressive environment.

The basis of the invention is the creation of a device for refining aluminum and alloys based on it with improved technical, economic and technological characteristics, which would allow to work out the entire volume of the melt in a non-contact way.

The problem is solved in that in a device for refining aluminum and alloys based on it, containing a lined container, a lined metal cover, a gas-distributing mechanism, a gas removal mechanism, a device for creating a rotational movement of the melt, according to the invention, a contactless device is used to create a rotational movement of the melt a multiphase inductor of a traveling electromagnetic field with a melt, and the lined metal cover is made of non-magnetic high oomnoy steel.

In this case, the traveling electromagnetic field inductor can be located on top of the lined metal cover or in its alignment, as well as under the lined metal cover.

The manufacture of the cap from non-magnetic high-resistance steel ensures the penetration of the electromagnetic field into the melt, which allows the entire volume of the melt to be processed in a non-contact way, while the manufacture of the cap from magnetic material, the flows created by the coils will be closed along it and the necessary technical result will not be achieved.

Figure 1 shows the proposed device for refining aluminum and alloys based on it with the location of the inductor on top of the lined metal cover, front view; figure 2 is the same, a top view; figure 3 shows the proposed device with the location of the inductor in the alignment of the cover; figure 4 is the same with the location of the inductor under the cover.

A device for refining aluminum and alloys based on it includes a lined metal container 1 on which a lid 2 with a metal frame 3 and a lining 4 is mounted. In the lid 2 there is a gas distribution mechanism 5, a gas removal mechanism 6, an inductor of a traveling electromagnetic field 7. In a lined metal container 1 is a molten aluminum 8.

The device operates as follows:

During transportation, the container 1 with the melt 8 is placed in the working area, where the cover 2 with the gas removal mechanism 6, the gas distribution mechanism 5 and the inductor 7 is placed on the container. When the coils of the inductor 7 are connected to an alternating voltage, an electric current flows through them, which creates magnetic fluxes. As a result of superposition of magnetic fluxes shifted in time and space, a traveling electromagnetic field is formed, similar to the stator field of an end induction motor. Interacting with the melt 8, the traveling electromagnetic field induces eddy currents in it, the magnetic field of which, in turn, interacts with the primary magnetic field, causes forces in the melt 8, which cause the latter to rotate.

As a result of intensive rotation of the melt, a funnel is formed in it, into the region of which a refining mixture 9 is supplied using a gas-distributing mechanism 5. Gases released as a result of the interaction of the refining mixture with alkali metals are removed using the gas removal mechanism 6.

The mixing process creates favorable conditions for the coagulation of inclusions of alkaline earth metals in aluminum melt with their subsequent removal. This is explained by the fact that in the melt zones with maximum flow velocities near its axis, increased concentrations of inclusions of alkaline earth metals are formed, which contribute to an increase in the frequency of collisions, and hence the coagulation of dispersed particles. After completion of the mixing process, the coagulated particles rise to the surface of the melt, where they are removed using a scraper. Mixing also significantly stimulates the diffusion of sodium from the bulk of the melt to the surface, where sodium is converted to oxide.

The proposed device has several advantages over the well-known:

- improves the efficiency of refining due to more intensive mixing;

- there is no need for direct contact of the rotator with liquid metal, which increases its service life;

- reduced costs for maintaining the healthy state of the device as a whole by increasing the service life of the device to create a rotational movement of the metal.

Claims (4)

1. A device for refining aluminum and alloys based on it, containing a lined container, a lined metal cover, a gas distribution mechanism, a gas removal mechanism and a device for creating a rotational motion of the melt, characterized in that a multiphase contactless melt is used as a device for creating a rotational motion of the melt a running electromagnetic field inductor, and a lined metal cover made of non-magnetic high-resistance steel. 2. The device according to claim 1, characterized in that the traveling electromagnetic field inductor is located on top of the lined metal cover. 3. The device according to claim 1, characterized in that the traveling electromagnetic field inductor is located in the alignment of the lined metal cover. 4. The device according to claim 1, characterized in that the traveling electromagnetic field inductor is located under the lined metal cover.

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