RU2457285C1 - Electrolysis unit for aluminium manufacture - Google Patents

Abstract

FIELD: metallurgy.

SUBSTANCE: electrolysis unit for aluminium manufacture includes the housing, bottom, electrode system that consists of end vertical or inclined anode, cathode and bipolar electrodes and feed system. The electrodes are movable with the possibility of changing the distance between them, note that the movable parts of the electrodes in a form of wheels and/or rollers are arranged outside the flux in relation to the working space of electrolysis unit well. Movable bipolar electrodes and one or both end electrodes installed at the wheels, rollers, transportation belt move in relation to the transverse axis of electrolysis unit with the aid of external space relatively filled with flux of device electrolysis unit. The bottom can be horizontal, inclined and equipped with metal receiver. It is possible to use hollow gas-filled bipolar electrodes for creation of gas-air medium through the holes in their anode side with formation of gas film that constraints the corrosion of electrode anode part. Aluminium oxide and fluorides feed system is located at the arch of electrolysis unit or separately in relation to electrolysis unit. Aluminium oxide feeding to electrolysis unit is done by way of aluminium oxide and fluorides feeding directly to the flux in the electrolysis unit well or by way of electrolysis unit saturation with aluminium oxide and fluorides in the reservoir external in relation to the electrolysis unit working space or flowing channel.

EFFECT: reduction of electrolysis unit size, total voltage and simplification of electrolysis unit maintenance.

6 cl, 1 dwg

Description

The invention relates to the field of non-ferrous metallurgy, to the electrolytic production of aluminum.

Known electrolyzer for producing aluminum according to patent RU 2041975. It contains a system of continuous anodes made of prebaked anode blocks located with a gap and connected by fastening means on the longitudinal sides, cathode blocks, a collector for deposited aluminum, anode beams connected to the anode frame, panel shutters located on the sides of the cell, a bottom with thermal insulation and lining, and an automatic device for loading aluminum oxide. The disadvantages of this electrolyzer are the complexity of the design and high power consumption.

According to patent RU 2133304, an electrolytic cell for separating metals from solutions is known. It contains a housing, a cover, fixed anodes located in two rows, and disk cathodes rotating between them on a common shaft, current leads. However, this electrolyzer is not suitable for the production of aluminum on an industrial scale.

The closest analogue to the claimed electrolyzer is the electrolyzer according to patent RU 2401884. In the electrolyzer of this design, the anode part of the bipolar electrodes is made consumable, and the electrodes themselves are movable with the possibility of regulating the interelectrode space by moving the bipoles and one of the end electrodes along the false bottom on the rollers and / or rollers made of material resistant to aluminum and electrolyte. The disadvantage of this design is the presence of moving mechanisms in the melt (rollers and / or rollers), which significantly complicate the smooth industrial operation of this unit.

The objective of the proposed technical solution is to reduce the cost of aluminum produced by electrolysis by reducing the cost of the unit (electrolyzer) and reducing energy consumption.

The technical result consists in reducing the size of the cell, reducing the overall voltage of the cell by reducing the voltage in the anode and cathode, reducing the size and weight of the busbar, in simplifying maintenance of the cell.

The specified technical result is achieved by the fact that in the electrolyzer, the bipolar electrodes are made movable with the possibility of changing the interelectrode distance, and the movable parts of the electrodes (rollers and / or rollers) are removed from the melt to the outside relative to the mine - workspace - electrolyzer. The movable bipoles and one or both of the end electrodes can be mounted on rollers, rollers, a conveyor belt, or moved relative to the transverse axis of the electrolyzer using another device that is external to the melt-filled space of the cell. The hearth can be made horizontal, inclined, can be equipped with a money box for collecting metal. The walls of the cell shaft can be equipped with caissons with refrigerant to remove heat and lined from the inside with material resistant to melt (aluminum and electrolyte). Bipoles can be placed strictly vertically and at an angle to the horizontal, the anode part of the bipoles can have grooves-grooves of various configurations for effective gas removal. The cathode side of the bipole can be made of a material wetted by aluminum. It is possible to use hollow gas-filled bipoles to create a gas-air medium through openings in the anode side of the bipoles to create a gas film that limits the corrosion of the anode part of the bipole. The cell is equipped with a removable vault designed for evacuation of exhaust gases. The alumina and fluorine salt supply system may be located on the arch of the electrolyzer or separately relative to the electrolyzer. The alumina can be powered by feeding alumina and fluorine salts directly to the melt in the electrolyzer shaft, or by saturating the alumina and / or fluorine salts of the electrolyte in a reservoir external to the electrolyzer working space or in a flow channel.

Figure 1 shows a simplified General view of the electrolyzer for the production of aluminum.

The cell includes a metal housing 1, which can be equipped with caissons with refrigerant 2, with a lining 3 of materials resistant to liquid electrolyte 4 and metal, in which a system of vertical or inclined electrodes is located, consisting of end anode 5, end cathode 6 and bipolar electrodes 7. Current to the end electrodes is supplied through current leads 8.

The end anode 5, the bipolar electrodes 7 are structurally supported by an external (outside the melt) relative to the working space of the electrolyzer structural element of the electrolyzer 9. The electrodes can move relative to the transverse axis of the electrolyzer.

In the lower part of the electrolyzer, a metal piggy bank can be located near the inclined or horizontal hearth 10. On top of the electrolyzer is covered by a vault 11, which can be partially or completely removed. In the arch, a gas removal system is structurally provided, and an alumina feed system 12 can be equipped.

Bipolar electrodes have a cathode 13 and anode 14 sides. Bipolar electrodes on the anode side can be equipped with grooves grooves to improve gas removal. Bipoles can also be hollow with the possibility of pumping gases into them for the subsequent creation of a gas anticorrosion layer through holes in the anode side of the bipole.

The cell operates as follows.

The electrolyzer is launched after heating the internal space to a temperature comparable to the working temperature of the electrolyte (temperature difference is not more than 100 degrees Celsius). After heating, the previously deposited electrolyte is poured into the bath 4. The electrolyte can be curled both in the empty cell of the electrolyzer and in the shaft with previously introduced electrodes. After pouring the electrolyte and installing the electrodes, an electric current is turned on and arch 11 is installed.

The use of bipolar electrodes connected in series and the use of a relatively small current strength reduces the mass of the busbar used for current supply, reduces the overall voltage, thereby reducing energy consumption.

Due to the non-participation of the obtained liquid metal in the process of current flow, there is no need to maintain a sufficiently large amount of metal in the cell of the electrolyzer.

Claims (6)

1. An electrolytic cell for aluminum production, comprising a housing, a hearth, an electrode system consisting of end vertical or inclined anodes, a cathode and bipolar electrodes, and a power supply system, characterized in that the electrodes are made with moving parts with the possibility of changing the interelectrode distance, the moving parts electrodes made in the form of rollers and / or rollers are taken out of the melt outward relative to the working space of the cell of the electrolyzer. 2. The electrolyzer according to claim 1, characterized in that the movable bipolar electrodes and one or both of the end electrodes are configured to be mounted on rollers, rollers, a conveyor belt, or moved relative to the transverse axis of the cell using an external device relatively relatively filled with the melt space of the cell. 3. The electrolyzer according to claim 1, characterized in that the hearth is horizontal inclined and equipped with a money box for collecting metal. 4. The electrolyzer according to claim 1, characterized in that it is made with the possibility of using hollow gas-filled bipolar electrodes to create a gas-air medium through holes in the anode side of the bipolar electrodes with the formation of a gas film that limits the corrosion of the anode part of the bipolar electrode. 5. The electrolyzer according to claim 1, characterized in that the alumina and fluoride salt feed system is located on the vault of the cell or separately relative to the cell. 6. The electrolyzer according to claim 1, characterized in that the electrolyzer is fed with alumina by supplying alumina and fluoride salts directly to the melt in the cell of the electrolyzer or by saturating the alumina and / or fluoride salts of the electrolyte in a reservoir external to the working space of the cell or in a flow channel.

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