RU2282680C1 - Electrolyzer for production of aluminum - Google Patents

Abstract

FIELD: non-ferrous metallurgy; aluminum production electrolyzers.

SUBSTANCE: proposed electrolyzer involves side surfaces of anode channels in operation, thus increasing working (effective) surfaces of anode and cathode and reducing losses of electric power in anode and in electrolyte. Proposed electrolyzer has carbon anodes with channels and cathode unit including layer of molten aluminum on hearth; cathode current-transfer rods are made from materials which are non-soluble in aluminum; their upper part extending above molten aluminum has shape corresponding to shape of opposite channels in anode; it is located in anode channels at distance of 1.0-6.0 cm in parallel with side surfaces of channels. Channels in carbon anodes and upper part of cathode current-transfer rods extending above molten aluminum surface have triangular section. When use is made of non-consumable anodes, shape of channel and upper part of cathode rod may be rectangular, for example.

EFFECT: reduced losses of electric power in anode and in electrolyte; reduced power requirements.

2 cl, 2 dwg

Description

The invention relates to ferrous metallurgy, in particular to the electrolytic production of aluminum, and in particular to the design of an electrolytic cell for aluminum production.

A known design of the electrolytic cell for the production of aluminum, containing carbon anodes and a cathode device, the bottom of which is covered with a layer of liquid aluminum, which is the cathode of the electrolyzer (Reference metallurgist non-ferrous metals. Aluminum production. M .: Metallurgy, 1971, p. 154).

The disadvantage of this design is that the gas released on the working surface of the anode creates additional resistance to the passage of electric current and leads to additional losses of electric power and an increase in the energy consumption for aluminum production.

A known design of an electrolytic cell for the production of aluminum, which is adopted as a prototype, containing an anode and cathode device, on the bottom of which there is a layer of liquid metal, and the calcined carbon anodes have one or more vertical channels on their working surfaces. (B.P. Moxnes, B.E. Aga, J.H.Skaal "How to obtain open feeder holes by installing anodes with tracks". Light Metals, 1998, pp. 247-255).

This design allows you to accelerate the removal of the gas phase beyond the working surface of the anode and to reduce the loss of electrical power and energy consumption due to the electrical resistance of the gas phase released on the surface of the anode.

The disadvantage of this design of the electrolyzer is that the lateral surfaces of the vertical channels of the anodes, being remote from the surface of the liquid metal (cathode), do not participate in the electrolysis process and reduce the effective working surface of the anodes, which leads to an increase in the loss of electric power in the anode and in the electrolyte and, accordingly, electricity consumption for aluminum production.

An object of the present invention is to provide a design of an electrolyzer that allows the side surfaces of the channels of the anodes to be involved in the electrolysis process, thereby increasing the working (effective) surface of the anodes, and reducing the loss of electric power in the anode and in the electrolyte and the energy consumption for aluminum production.

The achievement of the above technical result is ensured by the fact that in the electrolytic cell for the production of aluminum, containing carbon anodes with channels and a cathode device with a layer of liquid aluminum on the bottom and cathode collector rods, according to the claimed invention, the cathode collector rods are made of insoluble materials in aluminum, and their upper the part protruding from liquid aluminum is made in the form corresponding to the shape of the opposite channels in the anode, and is located in the channels of the anodes parallel to them side surfaces at a distance of 1.0-6.0 cm from them.

In order to ensure the constancy of the distance between the anode and cathode as the anode array is burned and lowered, when consumable carbon anodes are used, the channels in them and the upper part of the cathode collector rods are made in the form of a triangular section.

The location of the cathode collector rods above the surface of the liquid metal parallel to the side surfaces of the anode channels increases the working (effective) surface of the anode and cathode by about 10% (calculated). This will provide a proportional reduction in electrical power losses and a reduction in energy consumption of approximately 5%.

The distance from the side surfaces of the channels to the surface of the protruding part of the cathode collector rods is selected from the condition of preventing direct contact of the released aluminum and anode gases. According to laboratory studies, this distance should be at least 1.0 cm. A decrease in this distance less than 1.0 cm will lead to a significant decrease in the current output of aluminum. An increase in this distance of more than 6.0 cm will lead to a proportional increase in the loss of electric power in the electrolyte and the energy consumption for aluminum production. To maintain a constant distance between the anodes and the cathode collector rods as the carbon anodes are consumed and lower, the channels and protruding parts of the cathode collector rods protruding from liquid aluminum have a triangular cross section, provided that the distance between them is 1.0-6.0 cm.

The invention is illustrated by drawings, where figure 1 shows a longitudinal section of an electrolyzer with carbon consumable anodes, and figure 2 is a longitudinal section of an electrolyzer with non-consumable anodes.

The cell for the production of aluminum contains carbon anodes 1 with channels 2 and a cathode device 3 with a layer of liquid aluminum 4 on the hearth 5. The cathode collector rods 6 are made of insoluble materials in aluminum, and their parts protruding from the liquid aluminum are located in the channels of the anodes at a distance of 1, 0-6.0 cm parallel to the lateral surfaces of the channels 2. When using carbon sacrificial anodes, the anode channels and parts of the cathode collector rods protruding above the aluminum surface have a triangular section, and when using Non-consumable anodes - any other, for example, rectangular. The cathode collector rods 6 are mounted in a hearth and transmit current through a layer of liquid metal to the cathode busbar 7.

The proposed design of the electrolyzer allows to increase the working (effective) surface of the anode and cathode, to reduce the loss of electric power and energy consumption for aluminum production.

Claims (2)

1. The cell for the production of aluminum, containing carbon anodes with channels and a cathode device with a layer of liquid aluminum on the bottom and cathode collector rods, characterized in that the cathode collector rods are made of insoluble materials in aluminum, and their upper part protruding from liquid aluminum , made in the form corresponding to the shape of the opposite channels in the anode, and is located in the channels of the anodes parallel to their lateral surfaces at a distance of 1.0-6.0 cm from them. 2. The electrolyzer according to claim 1, characterized in that when using consumable carbon anodes, the channels in them and the upper part of the cathode collector rods are made in a shape having a triangular section.

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