RU55777U1 - DEVICE FOR CONTINUOUS REFINING OF ALUMINUM MELT - Google Patents

Abstract

The inventive object relates to techniques for processing molten aluminum alloy and can be used in metallurgy. A device for continuous refining of aluminum melt, contains a drain chute equipped with a coarse filter and a container divided into a drain section, a gas refining section with lances for supplying refining gas with a ceramic partition separating these sections and a fine filter section with fine filters inside. It differs in that the coarse filter is installed on the drain trough, the ceramic partition is inclined towards the gas refining section and is located in the guides with the possibility of translational movement. The technical result from the application of the proposed technical facility is to simplify its maintenance.

Description

The utility model relates to techniques for processing molten aluminum alloy and can be used in metallurgy.

The prior art devices for refining aluminum and its alloys mounted on the drain trough, which allows for continuous processing of the melt. RF patent No. 2090639 [1] OJSC “Volgograd aluminum” and OJSC “VAMI” claimed the design of such a device consisting of a crucible located on the drain chute, divided into two chambers with a partition not reaching the bottom, equipped with a gas distribution device and a ceramic foam filter. The gas distribution device and filter are placed in one of the chambers with the specified parameters for immersion in the melt.

The disadvantage of this device is the insufficient degree of purification of the melt from solid particles, since only one filter is used in its design.

The Italian company "ALUMINIA SPA" received a European patent EP 0291580 [2] for the design of equipment for degassing and filtering molten aluminum in the stream. The device consists of a thermally insulated container equipped with heating means. The tank is divided into two chambers equipped with a notch for overflowing metal, two tuyeres for supplying inert and active gases, as well as a horizontal partition made of porous material, which plays the role of a filter. In this case, the metal is fed through the filter from the bottom up, which allows the laminar flow of the melt to be achieved.

The disadvantage of this device is the insufficient degree of filtration, since the design provides only one filter.

European patent EP 0476534 [3] by the German company VAW VER ALUMINUM WERKE AG claimed the design of apparatus for refining aluminum melt. The equipment is a round container equipped with a removable lid and divided into round compartments. The central compartment is formed by a pipe in the cavity of which an impeller is fixed. The device also contains a set of concentric partitions, between which containers are formed for stepwise processing of the melt. The melt is fed through the central compartment, and leaves the device through the last peripheral tank.

The disadvantage of this device is its large dimensions, since the transfer of metal occurs through a set of concentric compartments, the diameter of each of which is gradually increasing.

SOUTHWIRE COMPANY obtained US patent No. 3039864 [4], which describes a device for processing molten light metals, such as aluminum, to remove solid and gaseous impurities. The device contains a container for molten metal, divided into two sections by a partition that does not reach the bottom of the vessel. In the first section along the supply of the melt, a filter element is installed in the form of granules made of a material inert with respect to the melt. In the same section there is a lance for purging the melt with inert gas, with a gas outlet below the filter element. The molten aluminum flows from the first section to the second, freeing from impurities. The disadvantage of the analogue is the two-section design of the device, which does not allow to fully realize the complete filtration of the melt.

UK patent No. 1428146 [5], issued to the American company ALUMINUM CO OF AMERICA, protects the design of the refining plant for aluminum melt, which is made in the form of a vessel having an inlet and an outlet for flow

melt. The capacity is divided by partitions into separate chambers, in one of which tuyeres for supplying chlorine-containing gas are placed. The first chamber, which contains both molten metal and slag, is divided by additional partitions into three parts. In two of them, different types of gases are supplied by two different tuyeres for processing and mixing the melt. The second chamber is separated from the first chamber by a partition protruding from above the melt, which allows the slag layer to be separated. From this chamber, the melt enters the drain pan.

The disadvantage of this analogue is the lack of means for adjusting the speed of passage of the melt.

The prior art also known installation design for continuous refining of aluminum and its alloys by AS USSR No. 621774 [6]. The device comprises a container divided by a partition into a drain chamber and a refining chamber. A degassing device is installed above the refining chamber, which is divided by a partition with holes in its lower part into a metering chamber and a degassing chamber. The metering chamber contains a valve for adjusting the flow of metal. The drain chamber is connected to a tray leading the melt away from the installation. The disadvantage of this device is the lack of tuyeres for supplying refining gas, which makes it impossible to carry out complete refining of the metal.

The prior art also known a device for continuous refining of aluminum melt, patented by SOUTHWIRE COMPANY (US patent No. 4067731 [7]), selected as a prototype.

The device provides for the implementation of the refining process in four stages, for which four sections are provided in the total capacity: drain, gas refining, adsorption purification and fine filtration.

The drain section contains vertically mounted ceramic partitions made of fiberglass and serves to separate large particles from the melt.

The gas refining section contains a set of vertical partitions not reaching the bottom of the tank. Between the partitions there are tuyeres for supplying refining gas. The lances are made in the form of pipelines and prismatic nozzles made of porous ceramic material, for example, graphite. With their help, hydrogen dissolved in the metal is removed.

The adsorption cleaning section contains a set of horizontally arranged plates made of a material having the property of adsorption with respect to impurities. Such material is calcium oxide, if there is a need to clean the melt of iron and lead. The molten aluminum flows along the surfaces of the plates, due to which the adsorption process is carried out.

The fine filtration section contains a set of U-shaped fine filters made of small particles of alumina. In this section, the final melt filtration takes place. The second and fourth sections are equipped with burners for heating the melt.

A disadvantage of the known device is the increased energy consumption due to the presence of a large number of sections and contact surfaces having increased heat transfer. That is why the developers had to provide the unit with additional means of heating the melt.

In the proposed device, the drain section contains vertically mounted porous partitions, and serves to separate foreign particles from the melt of large sizes. Unlike the prototype, porous partitions are installed in the drain trough, and not in the tank. This allows you to delay foreign particles during the laminar flow of metal in

the gutter and prevent them from mixing in the melt when a metal stream enters the tank, where conditions of turbulent movement of the melt are created.

The gas refining section is separated from the drain section by a partition and contains a lance or lances for supplying refining gas. Unlike the prototype, the partition is inclined towards the gas refining section and is located in the guides with the possibility of translational movement. The implementation of the inclined partitions allows you to increase the space of the drain chamber in its upper part, which creates the possibility of easier access to remove slag. The location of the partition in the guides creates the possibility of translational movement and adjustment of the flow of metal coming from the drain chamber to the refining chamber. In addition, the conditions for cleaning this section from heavy particles settled to the bottom are improved, since the partition can be removed by moving along the guides.

The fine filtration section contains two filters installed in series and vertically, made of ceramic foam material.

The figure shows the layout of the elements in the proposed device.

The device (figure) consists of a drain chute 1 and a container 2, divided into a drain section 3, a gas refining section 4 and a fine filter section 5 connected to a metal wire 6. The drain chute 1 is equipped with coarse filters 7 and 8. In the gas refining section is located lance 9 for supplying refining gas. The drain section 3 and the gas refining section 4 are separated by a ceramic partition 10, which is tilted towards the gas refining section with an angle of inclination of up to 45 °. Ceramic

the partition 10 is located in the guides 11 with the possibility of movement along these guides. In the fine filtration section, ceramic foam filters 12 and 13 of fine cleaning are arranged in the form of vertically arranged porous plates. At the exit of the fine filtration section, at the point where it adjoins the metal wire 6, the melt flow regulator 14 is located. The arrows indicate the direction of the melt movement.

A device for continuous refining of aluminum melt works as follows. The molten aluminum or its alloy is supplied from the mixer (not shown in the figure) through the groove 1 to the container 2. On its way there are coarse filters 7 and 8, on which relatively large foreign inclusions are delayed. In the discharge section 3, the melt is processed by a coating-refining flux and enters the gas refining section 4. In this section, it is processed by a refining gas using a tuyere 9. By moving the ceramic partition 10 in the guides 11, the flow rate of the melt entering the gas refining section 4 is controlled achieving completeness of refining. The metal enters the fine filtration section 5 and, passing sequentially through the fine filters 12 and 13, is freed from small particles, after which it enters the metal conduit 6 through the melt flow regulator 14 and further into the pouring means (not shown in the figure).

When cleaning the device from dirt that has fallen on under the drainage chambers during operation of the device, the inclined design of the ceramic partition provides expanded space for easy cleaning. The ability to remove the partition along the guides allows you to clean the entire hearth without difficulty after the end of the device. These actions are difficult to implement in the device of the prototype, since it does not provide for the possibility of expansion

workspace for auxiliary operations. Unlike the option for processing heavy non-ferrous metal melts, aluminum oxides settle to the bottom, and do not float to the surface of the melt, therefore, regular cleaning of the hearth is required.

The technical result from the application of the proposed technical facility is to simplify its maintenance.

Bibliographic data

1. Patent of the Russian Federation No. 2090639. A device for refining aluminum and its alloys / A.I. Palenko et al. / Declares. "Volgograd aluminum" and YOU. MKI C 22 V 21/06, publ. 09/20/97.

2. Patent EP 0291580. Apparatus for in-line degassing and filtering of aluminum and its alloys. ALUMINIA SPA / Piros Leonardo. C 22 B 21/06. Publ 11/23/88.

3. Patent EP 0476534. Apparatus for the purification of molten non-ferrous metals, in particular molten aluminum. VAW VER ALUMINUM WERKE AG. C 22 B 9/05. Publ. 03/25/92.

4. US patent No. 3039864. Treatment of molten light metals. Appl. SOUTHWIRE COMPANY. Inv. P.D.Hess etc. NKI 75/67. Publ. 06/19/62.

5. UK patent No. 1428146. Purification of aluminum. ALUMINUM CO OF AMERICA. C 22 B 21/06. Publ. 06/17/03.

6. A.S. USSR No. 621774. Installation for continuous refining of aluminum and its alloys. L.G. Berezin et al. MKI C 22 B 21/06. Publ. 08/30/78.

7. US Patent No. 4067731. Method of treating molten metal. Appl. SOUTHWIRE COMPANY. Inv. Chia; Enrique S. NKI 75/406, MKI C 22 B 021/06. Publ. 01/10/77.

Claims (1)

A device for continuous refining of aluminum melt, comprising a drain chute equipped with a coarse filter and a container divided into a drain section, a gas refining section with lances for supplying refining gas with a ceramic partition separating these sections, and a fine filtration section with fine filters located inside characterized in that the coarse filter is installed on the drain trough, the ceramic partition is tilted towards the gas refining section and It is put in the guide in translation.