Cathode conductive structure of aluminum electrolysis cell

Abstract

The utility model relates to the technical field of electrolytic production of aluminum by a molten liquid electrolysis method, in particular to a cathode conductive structure of an aluminum electrolysis cell. The utility model provides a brand new cathode conductive structure of an aluminum electrolysis cell, and compared with the prior art, the conductive structure between the cathode steel bar and the cathode aluminum bus is simplified by realizing conductive connection between the cathode steel bar and the cathode aluminum bus between the steel-aluminum composite soft belts, and meanwhile, parts needing to be welded are reduced; the problems of large welding workload and low welding efficiency caused by surfacing are solved, the reduction of welding parts further reduces the voltage drop of the cathode conductive structure, and the energy consumption in the aluminum electrolysis process is reduced.

Description

Technical Field

[0001] This utility model relates to the technical field of aluminum production by electrolysis of molten liquid, and particularly to the cathode conductive structure of aluminum electrolysis cells. Background Technology

[0002] An aluminum electrolytic cell is the main equipment for producing aluminum by electrolysis, and the cathode carbon block assembly is one of the core components of the aluminum electrolytic cell. The cathode carbon block assembly includes cathode carbon blocks and cathode steel rods embedded in the bottom of the cathode carbon blocks by means of cathode tamping paste or casting with pig iron. One end of the cathode steel rod protrudes from the cathode carbon block and is connected to the cathode aluminum busbar via conductive components. During the aluminum electrolysis production process, the current sequentially flows through the anode assembly, electrolyte, molten aluminum, cathode carbon blocks, and cathode conductive structure into the cathode aluminum busbar, and then flows into the anode of the next electrolytic cell.

[0003] Traditional cathode conductive structures such as Figure 1 As shown, multiple connecting steel plates 4 are welded to one end of the cathode steel rod 3 extending from the cathode carbon block 1. The other ends of the connecting steel plates 4 are welded to the steel portion 50 of the steel-aluminum explosive block. Multiple aluminum flexible strips 6 are welded to the aluminum portion 51 of the steel-aluminum explosive block, and the other ends of the aluminum flexible strips 6 are connected to the cathode aluminum busbar 7. This cathode conductive structure requires the connecting steel plates to be welded to both ends of the cathode steel rod and the steel-aluminum explosive block, resulting in a large number of welds and making it difficult to guarantee welding quality. This leads to increased voltage drop and power consumption. Furthermore, the connecting steel plates are often thin, and their effective conductive area is smaller than the end face area of ​​the cathode steel rod, again resulting in increased voltage drop and power consumption.

[0004] To address the aforementioned issues, the Chinese utility model patent with authorization announcement number CN203866387U discloses a welding structure for a cathode steel rod and aluminum flexible strip used in an electrolytic cell. One end of the cathode steel rod, exposed above the cathode carbon block, is welded to the steel portion of a steel-aluminum composite block via a bottom steel sheet. A weld overlay area is then formed between the cathode steel rod and the steel-aluminum composite block above the steel sheet. Welding is then performed in this area to completely connect the cathode steel rod and the steel-aluminum composite block. The end face of the aluminum portion of the steel-aluminum composite block is welded to multiple aluminum flexible strips, which are then connected to the cathode aluminum busbar. In this scheme, the cathode steel rod and the steel-aluminum explosive block are connected by overlay welding, which eliminates the problems of difficult welding quality control, large number of welds, and reduced effective conductive area that are easily caused by using multiple connecting steel plates. This reduces the voltage drop to a certain extent. However, the overlay welding method results in a large amount of welding work, and the entire overlay welding block is intermittently welded, with each interval being more than an hour, which greatly reduces the connection efficiency of the cathode conductive structure. In addition, due to the resistance of the overlay body and the resistance of the welds at both ends of the aluminum soft strip, the voltage drop of the conductive structure is still relatively high. Utility Model Content

[0005] The purpose of this invention is to provide a cathode conductive structure for aluminum electrolysis cells, which solves the problems of large workload, low efficiency, and large voltage drop in existing cathode conductive structures for aluminum electrolysis cells.

[0006] The cathode conductive structure of the aluminum electrolysis cell of this utility model includes a cathode steel rod and a cathode aluminum busbar. The cathode steel rod and the cathode aluminum busbar are electrically connected by a conductive component. The conductive component includes multiple steel-aluminum composite flexible strips. The steel end of the steel-aluminum composite flexible strip is welded to the cathode steel rod, and the aluminum end of the steel-aluminum composite flexible strip is electrically connected to the cathode aluminum busbar.

[0007] Furthermore, the steel-aluminum composite flexible strip is composed of multiple steel-aluminum composite flexible sheets stacked together.

[0008] Furthermore, the steel-aluminum composite film is an annealed film.

[0009] Furthermore, the steel-aluminum composite interface of the steel-aluminum composite film is a sloping surface that extends from one side of the film near the end position to the other side near the end position.

[0010] Furthermore, the length of the steel-aluminum composite interface is greater than twice the thickness of the steel-aluminum composite film.

[0011] Furthermore, the thickness of the steel-aluminum composite film is between 0.1 and 1 mm.

[0012] Furthermore, the thickness of the steel-aluminum composite flexible strip is between 5-10mm.

[0013] Furthermore, the steel-aluminum composite flexible strips are stacked in the vertical direction, with adjacent layers placed close together.

[0014] Furthermore, the aluminum end of the steel-aluminum composite flexible strip is welded to the cathode aluminum busbar.

[0015] This invention provides a novel cathode conductive structure for aluminum electrolysis cells. By using steel-aluminum composite flexible strips to achieve conductive connection between the cathode steel rod and the cathode aluminum busbar, the conductive structure between the cathode steel rod and the cathode aluminum busbar is simplified compared to the prior art. At the same time, it reduces the number of welding parts, eliminates the problems of large welding workload and low welding efficiency caused by overlay welding, and the reduction of welding parts further reduces the voltage drop of the cathode conductive structure, thereby reducing the energy consumption in the aluminum electrolysis process. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the cathode conductive structure in a traditional aluminum electrolysis cell.

[0017] Figure 2 This is a schematic diagram of one embodiment of the conductive cathode structure of the aluminum electrolysis cell of this utility model;

[0018] Figure 3 for Figure 2 A schematic diagram of the steel-aluminum composite sheet included in the steel-aluminum composite flexible strip.

[0019] In the diagram: 1. Cathode carbon block; 2. Stirring paste; 3. Cathode steel rod; 4. Connecting steel sheet; 50. Steel part of steel-aluminum explosive block; 51. Aluminum part of steel-aluminum explosive block; 6. Aluminum flexible strip; 7. Cathode aluminum busbar; 8. Steel-aluminum composite flexible strip; 80. Steel-aluminum composite flexible sheet; 82. Steel-aluminum composite interface; 83. Steel-aluminum composite section. Detailed Implementation

[0020] The features and performance of this utility model will be further described in detail below with reference to the embodiments.

[0021] The cathode conductive structure of this utility model uses a steel-aluminum composite soft strip to achieve a direct connection between the cathode steel rod and the cathode aluminum busbar. Compared with the prior art, which uses a steel-aluminum explosion block as an intermediate conductive component, and uses an aluminum soft strip, connecting steel sheet or weld overlay to achieve a conductive connection between the cathode steel rod and the cathode aluminum busbar, this simplifies the cathode conductive structure, reduces the number of welding parts, improves the connection efficiency, and further reduces the voltage drop.

[0022] Based on the above design concept, several different embodiments are provided below for illustration.

[0023] In a basic embodiment, such as Figure 2 As shown, the cathode conductive structure of the aluminum electrolysis cell includes a cathode steel rod 3 and a cathode aluminum busbar 7. The cathode steel rod 3 is fixedly embedded in the bottom of the cathode carbon block 1 using tamping paste 2. The cathode steel rod 3 and the cathode aluminum busbar 7 are electrically connected by conductive components, which include multiple steel-aluminum composite flexible strips 8. The steel ends of the steel-aluminum composite flexible strips are welded to the end faces of the cathode steel rod 3 that extend out of the cathode carbon block 1, and the aluminum ends of the steel-aluminum composite flexible strips are electrically connected to the cathode aluminum busbar 7. In different embodiments, different conductive connection methods can be used between the aluminum ends of the steel-aluminum composite flexible strips and the cathode aluminum busbar 7, such as welding or fastening with threaded fasteners.

[0024] In one embodiment, the steel-aluminum composite flexible strip 8 can be a single, integral strip; or in other embodiments, the steel-aluminum composite flexible strip 8 can be composed of multiple steel-aluminum composite flexible sheets 80 stacked in the thickness direction, forming a single steel-aluminum composite flexible strip 8. To improve the flexibility of the steel-aluminum composite flexible sheets 80, the steel-aluminum composite flexible sheets 80 can be annealed sheets. The steel-aluminum composite flexible sheets 80 are composite strips that achieve metallurgical bonding through composite processing, and are strip materials obtained through existing processes.

[0025] To facilitate welding and ensure a certain degree of flexibility, the thickness of the steel-aluminum composite flexible strip 8 can be between 5-10 mm, such as 5 mm, 6 mm, 8 mm, or 10 mm, for welding connections between the edge steel-aluminum composite flexible strip and the cathode steel rod and cathode aluminum busbar. When the steel-aluminum composite flexible strip 8 is a single integral strip, the thickness of the strip itself is the thickness of the steel-aluminum composite flexible strip 8. When the steel-aluminum composite flexible strip 8 is composed of multiple steel-aluminum composite flexible sheets 80 stacked together, the thickness of a single steel-aluminum composite flexible sheet 80 can be between 0.1-1 mm, such as 0.1 mm, 0.2 mm, 0.4 mm, 0.5 mm, 0.8 mm, or 1 mm.

[0026] Based on the above embodiments, in an optimized embodiment, the steel-aluminum composite flexible strips 8 are stacked in the vertical direction and adjacent layers are arranged close together. This can ensure that the current-carrying area of ​​the multiple steel-aluminum composite flexible strips 8 between the cathode steel rod 3 and the cathode aluminum busbar 7 is as close as possible to the end face area of ​​the cathode steel rod 3, thus avoiding a significant reduction in the current-carrying area and affecting the current-carrying capacity.

[0027] Based on the above embodiments, such as Figure 3 As shown, in an optimized embodiment, the steel-aluminum composite interface 82 of the steel-aluminum composite film 80 is a sloping surface extending obliquely from one side of the film near its end to the other side near its end. This results in a larger composite cross-section of the two materials, ensuring current flow and reducing resistance. In a preferred embodiment, the length of the steel-aluminum composite interface 82 is greater than twice the thickness of the steel-aluminum composite film 80.

[0028] The embodiments described above for this utility model have a simple structure and are easy to construct. During production, the cathode carbon block group reduces voltage drop by 15-20mV and reduces electricity consumption per ton of aluminum by 50-60kWh. For an electrolytic aluminum enterprise with an annual production capacity of 500,000 tons, this translates to at least 25 million kWh of electricity savings annually, resulting in significant economic benefits.

[0029] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. The patent protection scope of the present utility model shall be determined by the claims. Similarly, any equivalent structural changes made based on the description and drawings of the present utility model shall also be included within the protection scope of the present utility model.

Claims

1. A cathode conductive structure for an aluminum electrolytic cell, characterized in that, It includes a cathode steel rod and a cathode aluminum busbar, which are electrically connected by a conductive component. The conductive component includes multiple steel-aluminum composite flexible strips, the steel ends of which are welded to the cathode steel rod, and the aluminum ends of which are electrically connected to the cathode aluminum busbar.

2. The cathode conductive structure of the aluminum electrolytic cell according to claim 1, characterized in that, The steel-aluminum composite flexible strip is composed of multiple steel-aluminum composite flexible sheets stacked together.

3. The cathode conductive structure of the aluminum electrolytic cell according to claim 2, characterized in that, The steel-aluminum composite film is an annealed film.

4. The cathode conductive structure of the aluminum electrolytic cell according to claim 2 or 3, characterized in that, The steel-aluminum composite interface of the steel-aluminum composite film is a sloping surface that extends from one side of the film near the end to the other side near the end.

5. The cathode conductive structure of the aluminum electrolytic cell according to claim 4, characterized in that, The length of the steel-aluminum composite interface is greater than twice the thickness of the steel-aluminum composite film.

6. The cathode conductive structure of the aluminum electrolytic cell according to claim 2, characterized in that, The thickness of the steel-aluminum composite film is between 0.1 and 1 mm.

7. The cathode conductive structure of the aluminum electrolytic cell according to claim 1, 2, 3, or 6, characterized in that, The thickness of the steel-aluminum composite flexible strip is between 5-10mm.

8. The cathode conductive structure of the aluminum electrolytic cell according to any one of claims 1-3, characterized in that, The steel-aluminum composite flexible strips are stacked in the vertical direction, with adjacent layers placed close together.

9. The cathode conductive structure of the aluminum electrolytic cell according to any one of claims 1-3, characterized in that, The aluminum end of the steel-aluminum composite flexible strip is welded to the cathode aluminum busbar.

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