An aluminium reduction cell having a profiled end

Abstract

The application discloses an aluminum electrolysis cell with a special-shaped end, which comprises a cell body composed of a cell shell and an inner lining, an anode group, a cathode group and a crossbeam bus structure arranged above the cell body, the cell body comprises two large faces and two end faces, the two end faces are semicircular or trapezoidal, when the end face is semicircular, the cell shell is an elliptical cell shell, and correspondingly, the inner lining is an elliptical inner lining, when the end face is trapezoidal, the cell shell is a flat octagonal cell shell, and correspondingly, the inner lining is a flat octagonal inner lining. The aluminum electrolysis cell can conform to the flowing form of the melt area of the electrolysis cell, improves the uniformity of the hearth and the current distribution, and achieves the purposes of reducing the abnormal cell condition of the electrolysis cell and increasing the operation stability.

Description

An aluminum electrolytic cell with irregularly shaped ends Technical Field

[0001] This invention belongs to the field of aluminum electrolysis cell technology, and specifically relates to an aluminum electrolysis cell with irregularly shaped ends. Background Technology

[0002] With the continuous development and upgrading of aluminum electrolysis technology, the current in aluminum electrolysis has exceeded 600kA. Electrolytic cells are becoming increasingly larger, leading to greater variations in current distribution, alumina concentration distribution, temperature distribution, and furnace thickness distribution. This poses significant challenges to the current efficiency and control of the electrolytic cells. Currently, most aluminum electrolytic cells adopt a rectangular structure. In this type of cell, the melt region exhibits a flow pattern of two large vortices or multiple small vortices. The melt flow is poor at the four corners of the cell, resulting in slower heat exchange between the melt and the cell lining and even the external environment. This leads to a thicker furnace, resulting in uneven furnace thickness distribution. Consequently, uneven current distribution in the melt region, uneven anode consumption at the corners, large voltage fluctuations, and reduced current efficiency occur, negatively impacting the lifespan of the aluminum electrolytic cell. Meanwhile, the poor flowability at the corners of the existing rectangular electrolytic cells also leads to low local alumina transport performance, resulting in poor uniformity of alumina concentration distribution throughout the cell, reduced operational stability, and increased control difficulty. Summary of the Invention

[0003] The technical problem solved by this invention is: addressing the mismatch between the existing rectangular aluminum electrolytic cells and the melt flow pattern, which easily leads to excessively thick corner furnaces, uneven furnace thickness distribution, and uneven alumina concentration distribution, resulting in a series of problems such as reduced electrolytic cell efficiency and unstable operation. This invention provides an aluminum electrolytic cell with irregularly shaped ends, along with its supporting anode structure, cathode structure, crossbeam busbar arrangement, and cell cover structure, so that the ends of the electrolytic cell conform to the flow pattern of the melt zone, improving the uniformity of the furnace and current distribution, thereby reducing abnormal cell conditions and increasing operational stability.

[0004] The present invention solves the above problems through the following technical means:

[0005] An aluminum electrolytic cell with a special-shaped end includes a cell body composed of a cell shell and a lining, an anode group, a cathode group, and a crossbeam busbar structure arranged above the cell body. The cell body includes two large faces and two end faces. The two end faces are semi-circular or trapezoidal. When the end face is semi-circular, the cell shell is an elliptical cell shell, and correspondingly, the lining is an elliptical lining. When the end face is trapezoidal, the cell shell is a flat octagonal cell shell, and correspondingly, the lining is a flat octagonal lining. The crossbeam busbar structure includes a cross-connecting busbar, anode clamps, and a crossbeam busbar. The crossbeam busbar consists of eight segments, one segment for each of the two large faces, and three segments are provided for each of the two end faces, presenting a flat octagonal shape as a whole.

[0006] Furthermore, the anode group includes an end triangular prism-shaped anode group and a large-face cuboid-shaped anode group.

[0007] Furthermore, the end triangular prism-shaped anode group includes an end triangular prism-shaped anode carbon block, end anode steel claws, and an end anode guide rod.

[0008] Furthermore, the large-face cuboid-shaped anode group includes a large-face cuboid-shaped anode carbon block, large-face anode steel claws, and a large-face anode

[0009] Furthermore, the cathode group includes an end triangular prism-shaped cathode group and a large-face cuboid-shaped cathode group.

[0010] Furthermore, the end triangular prism-shaped cathode group includes an end triangular prism-shaped cathode carbon block and an end "屮"-shaped cathode steel bar.

[0011] Furthermore, the large-face cuboid-shaped cathode group includes a large-face cuboid-shaped cathode carbon block and a large-face cathode steel bar.

[0012] Furthermore, it further includes an end arc-shaped cell cover plate and an end trapezoidal cell cover plate.

[0013] The beneficial effects of the present invention:

[0014] (1) An aluminum electrolytic cell with a special-shaped end is proposed to replace the traditional rectangular-structured aluminum electrolytic cell, conforming to the flow field pattern of the melt region in the electrolytic cell, promoting the full heat exchange between the melt region and the cell wall surface, forming a hearth with a uniform thickness distribution, and avoiding the phenomenon of thickened hearth at the corners of the traditional rectangular aluminum electrolytic cell.

[0015] (2) In the aluminum electrolytic cell with a special-shaped end, the cell wall surface is basically coincident with the vortex edge of the melt region, and the velocity difference in the melt region of the electrolytic cell becomes smaller, avoiding the situation where the flow velocity at the corners of the traditional aluminum electrolytic cell is too low and the overall flow velocity distribution difference is large, which in turn leads to insufficient alumina transportation and poor uniformity of alumina concentration distribution.

[0016] (3) The proposed end-shaped aluminum electrolytic cell is equipped with an electrode structure in the shape of an end triangular prism, as well as a flat octagonal crossbeam busbar and a jumper busbar at the upper part, enabling the currents on the two large surfaces to be interconnected at the end of the aluminum electrolytic cell, thereby improving the uniformity of the anode current distribution in the upper part of the electrolytic cell.

[0017] (4) Based on the above-mentioned proposed end-shaped aluminum electrolytic cell, the internal shape of the electrolytic cell hearth can be optimized, as well as the uniformity of the flow field distribution, alumina concentration distribution, and anode current distribution. Furthermore, the stability of the electrolytic cell operation is increased, the frequency of abnormal conditions in the electrolytic cell is reduced, and thus the operation efficiency of the electrolytic cell can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The present invention will be further described below in conjunction with the drawings and embodiments.

[0019] FIG. 1 is a schematic cross-sectional structure diagram of the anode of an aluminum electrolytic cell with a semi-circular end in the embodiment;

[0020] FIG. 2 is a schematic cross-sectional structure diagram of the anode of an aluminum electrolytic cell with a trapezoidal end in the embodiment;

[0021] FIG. 3 is a schematic diagram of the distribution of the crossbeam busbar, jumper busbar, and anode clamp at the upper part of the aluminum electrolytic cell in the embodiment;

[0022] FIG. 4 is a schematic diagram of the triangular prism-shaped anode group at the end of the aluminum electrolytic cell in the embodiment;

[0023] FIG. 5 is a schematic diagram of the cuboid-shaped anode group on the large surface of the aluminum electrolytic cell in the embodiment;

[0024] FIG. 6 is a schematic diagram of the triangular prism-shaped cathode group at the end of the aluminum electrolytic cell in the embodiment;

[0025] FIG. 7 is a schematic diagram of the "屮"-shaped cathode steel bar at the end of the aluminum electrolytic cell in the embodiment;

[0026] FIG. 8 is a schematic diagram of the cuboid-shaped cathode group on the large surface of the aluminum electrolytic cell in the embodiment;

[0027] FIG. 9 is a schematic diagram of the arc-shaped tank cover at the end of the aluminum electrolytic cell in the embodiment;

[0028] FIG. 10 is a schematic diagram of the trapezoidal tank cover at the end of the aluminum electrolytic cell in the embodiment;

[0029] FIG. 11 shows the results of the flow field simulation calculation of a 400 kA aluminum electrolytic cell;

[0030] FIG. 12 shows the comparison of the simulation calculation contours of the hearth of a 400 kA traditional rectangular aluminum electrolytic cell and the elliptical electrolytic cell in the embodiment;

[0031] Figure 13 shows the simulation calculation profile of the hearth of a 400 kA aluminum electrolytic cell with a trapezoidal end in the embodiment.

[0032] Reference numerals in the figure:

[0033] 1 - Oval cell shell, 2 - Oval inner lining, 3 - End triangular prism-shaped anode group, 4 - Large-face cuboid-shaped anode group, 5 - Flat octagonal cell shell, 6 - Flat octagonal inner lining, 7 - Cross-connecting busbar, 8 - Anode clamp, 9 - Crossbeam busbar, 10 - End triangular prism-shaped cathode group, 11 - Large-face cuboid-shaped cathode group, 12 - End arc-shaped cell cover plate, 13 - End trapezoidal cell cover plate, 301 - End triangular prism-shaped anode carbon block, 302 - End anode steel claw, 303 - End anode guide rod, 401 - Large-face cuboid-shaped anode carbon block, 402 - Large-face anode steel claw, 403 - Large-face anode guide rod, 1001 - End triangular prism-shaped cathode carbon block, 1002 - End "屮"-shaped cathode steel bar, 1101 - Large-face cuboid-shaped cathode carbon block, 1102 - Large-face cathode steel bar. Specific embodiments

[0034] The present invention will be further described in detail below through embodiments. Through these descriptions, the features and advantages of the present invention will become clearer and more distinct. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments.

[0035] As shown in FIGS. 1 to 10, the aluminum electrolytic cell with a special-shaped end in this embodiment includes a cell body composed of a cell shell and an inner lining, an anode group, a cathode group, and a crossbeam busbar structure arranged above the cell body. The cell body includes two large faces and two end faces. The two end faces are semi-circular or trapezoidal. When the end face is semi-circular, the cell shell is an oval cell shell 1, and correspondingly, the inner lining is an oval inner lining 2. When the end face is trapezoidal, the cell shell is a flat octagonal cell shell 5, and correspondingly, the inner lining is a flat octagonal inner lining 6. Referring to FIGS. 12 and 13, for an aluminum electrolytic cell with a semi-circular end / overall oval shape, its end is equipped with an arc-shaped cell cover plate 12; for an aluminum electrolytic cell with a trapezoidal end / overall flat octagonal shape, its end is equipped with a trapezoidal cell cover plate 13.

[0036] The anode group includes an end triangular prism-shaped anode group 3 and a large-face cuboid-shaped anode group 4. Referring to FIGS. 4 and 5, the end triangular prism-shaped anode group includes an end triangular prism-shaped anode carbon block 301, an end anode steel claw 302, and an end anode guide rod 303. The large-face cuboid-shaped anode group includes a large-face cuboid-shaped anode carbon block 401, a large-face anode steel claw 402, and a large-face anode guide rod 403. The included angle α between the three sides of the triangular prism-shaped anode carbon block is 60°.

[0037] The cathode group includes an end triangular prism-shaped cathode group 10 and a large-face cuboid-shaped cathode group 11. Referring to FIGS. 6 and 7, the end triangular prism-shaped cathode group includes an end triangular prism-shaped cathode carbon block 1001 and an end "屮"-shaped cathode steel bar 1002. Referring to FIG. 8, the large-face cuboid-shaped cathode group includes a large-face cuboid-shaped cathode carbon block 1101 and a large-face cathode steel bar 1102. The "屮"-shaped cathode steel bar is mainly used to match the fan-shaped cathode carbon block, so that the cathode current is more evenly distributed. The current flows from the ends of the three protruding cathode steel bars and then connects to the cathode flexible strip. The included angle β between the three sides of the triangular prism-shaped cathode carbon block is 60°. The crossbeam bus structure includes a cross-connecting bus 7, an anode clamp 8 and a crossbeam bus 9; the crossbeam bus is composed of eight sections, one section for each of the two large faces, and three sections are arranged at each of the two end faces, and the whole is in the shape of a flat octagon.

[0038] Specifically, referring to FIG. 3, the flat octagon-shaped crossbeam bus 9 is arranged at the upper part of the electrolytic cell. There are evenly distributed anode clamps 8 on the crossbeam bus. The straight-section crossbeam buses on the two large faces are connected by a cross-connecting bus 7 to achieve the interconnection and intercommunication of the upper anode current.

[0039] Application Example 1:

[0040] Taking a 400 kA elliptical aluminum electrolytic cell as an example, the length and width of the main structure of the electrolytic cell are 17.8 m and 4.12 m respectively. 20 groups of cuboid-shaped anode carbon block groups and cathode carbon block groups are arranged on the two large faces of the electrolytic cell, and 3 groups of triangular prism-shaped anode carbon block groups and cathode carbon block groups are arranged at the flue end and the aluminum tapping end respectively. The angles α and β of the three sides of the triangular prism are both 60°. At the same time, a flat octagon-shaped crossbeam bus is arranged at the upper part. 20 groups of anode clamps corresponding to the cuboid anode carbon block groups are arranged on the straight-section crossbeam buses of the two large faces, and 3 groups of anode clamps corresponding to the end triangular prism-shaped anode carbon block groups are arranged on the crossbeam buses at the ends. By comparing the flow field simulation calculations of this elliptical electrolytic cell and a traditional rectangular electrolytic cell, it is found that the flow velocity in the melt area of the electrolytic cell is as shown in FIG. 11, presenting a state of two large vortices, which is more in line with the structure of the elliptical electrolytic cell; by comparing the thermal field simulations of the above two electrolytic cells and extracting the inner shape contour of the hearth through the primary crystallization temperature line of the electrolyte for comparison, as shown in FIG. 12, it can be seen from the figure that the hearth thickness of the elliptical aluminum electrolytic cell is more uniform, and there is no situation where the hearth at the corners of the rectangular aluminum electrolytic cell is thicker.

[0041] Application Example 2:

[0042] Under the condition that other design parameters are the same as those in Application Example 1, the cell shell and the lining of the electrolytic cell are designed into a flat octagon shape respectively. Similarly, the thermal field simulation of this electrolytic cell is carried out, and the inner shape of the hearth of this electrolytic cell is as shown in FIG. 13. It is found that the situation where the hearth at the corners is thicker is also eliminated, and the inner shape of the hearth appears to be more uniform.

[0043] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. An aluminum electrolytic cell with irregularly shaped ends, characterized in that: It includes a cell body composed of a cell shell and a lining, an anode group, a cathode group, and a crossbeam busbar structure arranged above the cell body. The cell body includes two large faces and two end faces. The two end faces are semicircular or trapezoidal. When the end face is semicircular, the cell shell is an elliptical cell shell, and correspondingly, the lining is an elliptical lining. When the end face is trapezoidal, the cell shell is a flat octagonal cell shell, and correspondingly, the lining is a flat octagonal lining. The crossbeam busbar structure includes a cross-connecting busbar, anode clamps, and a crossbeam busbar. The crossbeam busbar is composed of eight segments, one segment for each of the two large faces, and three segments are provided for each of the two end faces, presenting an overall flat octagonal shape. The anode group includes an end triangular prism-shaped anode group and a large-face cuboid-shaped anode group.

2. The aluminum electrolytic cell with irregularly shaped ends according to claim 1, characterized in that: The end triangular prism-shaped anode group includes an end triangular prism-shaped anode carbon block, end anode steel claws, and end anode guide rods.

3. The aluminum electrolytic cell with irregularly shaped ends according to claim 2, characterized in that: The large-face cuboid-shaped anode group includes a large-face cuboid-shaped anode carbon block, large-face anode steel claws, and large-face anode guide rods.

4. The aluminum electrolytic cell with irregularly shaped ends according to claim 3, characterized in that: The cathode group includes an end triangular prism-shaped cathode group and a large-face cuboid-shaped cathode group.

5. The aluminum electrolytic cell with irregularly shaped ends according to claim 4, characterized in that: The end triangular prism-shaped cathode group includes an end triangular prism-shaped cathode carbon block and an end "屮"-shaped cathode steel bar.

6. The aluminum electrolytic cell with irregularly shaped ends according to claim 5, characterized in that: The large-face cuboid-shaped cathode group includes a large-face cuboid-shaped cathode carbon block and large-face cathode steel bars.

7. The aluminum electrolytic cell with irregularly shaped ends according to claim 6, characterized in that: It also includes end arc-shaped cell covers and end trapezoidal cell covers.

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