High-efficiency and environmentally friendly aluminum electrolytic cell

Abstract

The present invention relates to the field of aluminum smelting technology, and in particular to the field of aluminum electrolytic cell technology, and has made many improvements and innovations in response to some of the major defects and shortcomings of existing aluminum electrolytic cells. The present invention provides a new type of high-efficiency and environmentally friendly aluminum electrolytic cell, comprising an electrolytic cell support beam, an anode box, an anode, an anode conductor, an aluminum electrolytic cell asphalt fume purification device, an electrolytic cell heat insulation cover, and an electrolytic cell gas collection and feeding box, all arranged on the electrolytic cell edge plate. The new type of high-efficiency and environmentally friendly aluminum electrolytic cell replaces the pre-baked anode with a continuous self-baked small anode. The heat, gas, and dust generated during the electrolytic production process are sealed in a small, high-temperature space, and the generated flue gas is also purified in the cell. In aluminum electrolytic production, there is no need to replace anodes and related work, nor is there any need to insulate and cover the electrolytic cell. Production is more environmentally friendly, stable, and efficient. The number of front-line production employees can be reduced by more than 50%, and production costs are greatly reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of aluminum smelting, and in particular to the technical field of aluminum electrolytic cells. Background Art

[0002] Since the adoption of the Hall-Héroult alumina molten salt electrolysis method in 1886, the aluminum smelting industry has maintained a consistent approach and principles. However, the structure and performance of the aluminum reduction cell—the primary equipment used in cryolite-alumina molten salt electrolysis—have evolved significantly. Aluminum reduction cells have evolved through six stages: small prebaked anode cells, side-conducting continuous self-baking anode cells, upper-conducting continuous self-baking anode cells, large-capacity prebaked anode cells with edge processing, center-line prebaked anode cells, and center-point prebaked anode cells. Currently, the large, or so-called super-large, prebaked anode cells in operation in the aluminum electrolytic industry are center-point prebaked anode cells. With the continuous advancement of science and technology, rising energy costs, increasingly stringent environmental protection requirements, and rising labor costs, aluminum reduction cells are continuously evolving towards larger and more automated sizes. The 600KA prebaked anode electrolytic cell is the largest capacity aluminum electrolytic cell currently in production. In the future, there will be aluminum electrolytic cells with larger capacity, higher degree of automation and greater environmental protection put into production.

[0003] Although over the past century, through continuous exploration and the application of numerous scientific and technological advances, the structural performance of aluminum electrolytic cells has been greatly improved, and aluminum electrolysis production has become increasingly efficient and environmentally friendly, the overall structural performance of aluminum electrolytic cells, whether currently large pre-baked anode electrolytic cells or previously self-baked anode electrolytic cells, still has some major flaws and shortcomings.

[0004] Currently, large-scale prebaked anode aluminum electrolytic cells face the challenge of anode exchange during production. These cells must purchase prebaked anodes from external suppliers or manufacture them in-house at the company's carbon plant. These anodes are then assembled into conductive anode groups and installed in the electrolytic cells. During production, the remaining anodes must be constantly replaced with newly assembled conductive anode groups. Furthermore, these anodes require manual and mechanical processing, requiring significant investment in manpower, financial resources, and material resources to ensure the proper operation of the electrolytic cells. Furthermore, major drawbacks include dirty electrolytes, irregular furnace walls, and legs that frequently change, hindering long-term stable and efficient production. Technical managers constantly adjust process parameters based on cell conditions, while operators frequently perform manual operations to address these issues. This is primarily due to the insulation provided by a mixture of alumina and electrolyte covering the tops of the anodes, between the anodes (including the middle of the cell), and between the anodes and the sides and ends of the cell. This often results in localized burnout of the insulation layer, melting the solid electrolyte and causing large amounts of alumina to accumulate at the bottom of the cell. This also occurs during the anode change process, leading to a mixture of carbon slag and alumina in the electrolyte. In some cases, the legs grow longer and the sides thicken, while in others, the legs shorten and the sides thin or even disappear, resulting in irregular and unstable furnaces. Furthermore, hard lumps can form between the anodes, and lumps can float in the electrolyte. This impedes the flow of the liquid electrolyte, leading to varying alumina concentrations in different locations. Anode effect auto-extinguishing technology was invented a few years ago, but it's not practical or feasible for many companies, especially domestic ones. The primary reason is contaminated liquid electrolyte within the cell. A third major limitation is inadequate sealing of the electrolytic cell top during production, resulting in significant heat loss and the release of fumes and dust from the production environment. These issues are readily apparent during anode change and also occur regularly, often visible on site. For example, if the cell control box and gas control cabinet in the factory aren't cleaned for several days, they can accumulate dust. The main reason is that, in addition to the multiple discharge ports and burners during production, the gas collection device is located outside the insulated and sealed space. Therefore, the flue gas and dust coming out from the shell discharge port and burner fill the large space enclosed by the tank door cover and the upper facilities of the electrolytic cell. Due to the negative pressure, they are collected into the gas collection hood and flue. In this way, due to the gaps in the tank door cover and the need to open the tank door cover for some work, some flue gas and dust are easily dissipated into the on-site environment. The heat of the electrolytic cell is also lost from the shell discharge port, burner, and loose alumina electrolyte covering material to the large space enclosed by the tank door cover and the upper facilities of the electrolytic cell. Of the heat loss in the electrolytic cell, 55% is lost in the top, 38% in the sides, and 7% in the bottom. Most of the heat is lost from the top.

[0005] In the past, the major defects and shortcomings of self-baked anode aluminum electrolytic cells were: first, the asphalt smoke produced was not effectively purified, which seriously polluted the environment; second, in large-scale anode production, the gas produced by the electrolytic reaction was not removed in a timely and good manner, the electrolytic cell often developed lesions, and manual processing was required. The economic and technical indicators were poor, and its structure was not suitable for large-scale production; third, like the pre-baked cell, alumina was used as the insulation material for the upper part of the electrolytic cell, and the edge shell was processed to add alumina, which caused more serious furnace changes and dirty electrolyte problems than the pre-baked anode cell; fourth, the electrolytic cell was not well sealed, which was worse than the pre-baked cell, and the emission of smoke and dust was serious, and the heat loss of the cell was also very large. Summary of the Invention

[0006] The purpose of the present invention is to provide an effective solution to the above-mentioned long-standing defects and shortcomings of aluminum electrolysis cells and to provide a new, efficient and environmentally friendly aluminum electrolysis cell.

[0007] The present invention provides a new type of high-efficiency and environmentally friendly aluminum electrolytic cell, including an electrolytic cell support beam fixed on the electrolytic cell edge plate, an anode box installed on the support beam, an aluminum electrolytic cell asphalt fume purification device, an electrolytic cell heat insulation cover plate, and an electrolytic cell gas collection and feeding box. It also includes an anode placed in the anode box and an anode conductor connecting the anode and the positive aluminum busbar.

[0008] The new, highly efficient and environmentally friendly aluminum cell features a cell support beam installed along the cell walls. The support beam is constructed of high-temperature reinforced concrete (or thick steel plate), high-temperature calcium silicate board, and ceramic fireproof cloth. The high-temperature reinforced concrete (or thick steel plate) serves as the main load-bearing structure. Its top features two L-shaped grooves, each 5mm deep and 2mm longer than the anode box, and 1mm wider than the thickness of the anode box steel plate. The high-temperature calcium silicate board has a very low thermal conductivity, only 0.034W / m·K at room temperature and approximately 0.1W / m·K at 600°C. This effectively reduces the heat transferred from the high-temperature electrolyte to the high-temperature reinforced concrete (or thick steel plate). The ceramic fireproof cloth is high-temperature resistant and stable, directly exposed to the high-temperature electrolyte, protecting the high-temperature calcium silicate board for long-term integrity. This ensures the long-term stability of the support beam, which sits above the high-temperature electrolyte liquid. The support beam houses the anode box, asphalt fume purification unit, gas collection and feed box, and the thermal insulation cover of the central cell. The support beam provides support for the anode box. The anode can be made to the same size as the anode of the prebaked anode electrolytic cell, solving the problem that the self-baked anode electrolytic cell could not be large in the past. Now and in the future, the size of the large prebaked electrolytic cell can be the same as that of the new high-efficiency and environmentally friendly aluminum electrolytic cell.

[0009] The new, highly efficient and environmentally friendly aluminum cell system consists of dozens to hundreds of open-bottomed rectangular anode boxes mounted on support beams. Made of steel or stainless steel, they are roughly the same size as prebaked anodes and approximately 1,600 mm tall. A layer of high-temperature-resistant fabric lines the inner wall of the boxes, allowing anode raw materials to be added and baked into qualified anode cones without adhering to the boxes. The anode bodies can move up and down relative to the boxes to ensure smooth production. These numerous anode boxes have welded top steel plates with four slots for the anode conductive tape to enter the boxes and connect to the anodes. Anode pellet inlet devices are located on the sides of the boxes, along the upper outer wall. A built-in anode pellet distribution plate ensures that the anode pellets are evenly distributed over the anode bodies. A circular hole is welded below to a threaded pipe fitting, connecting to the asphalt fume purification system. The anode boxes also feature a pneumatic clamping device, consisting of a cylinder and a clamping plate, for use during busbar lifting operations.

[0010] The anodes in the anode box are connected to the anode busbar using aluminum conductors. Current flows from the anode busbar through the aluminum conductors to the anode cones. The base of the anode cones acts as the positive electrode in the electrochemical reaction. During production, the bottom anode is continuously consumed, new anode cones are continuously formed above, and the anode particles are continuously melted into liquid paste, ultimately sintering into a solid anode body. The aluminum conductive band below the 660°C solid anode body melts into the tank due to temperatures exceeding 660°C, and the aluminum conductive band is consumed. The anodes have four grooves of uniform depth inside, containing high-temperature liquid electrolyte, which also facilitates anode baking and gas removal. Throughout the production process, the anode cones, liquid paste, and anode particles maintain the same structural morphology, and the temperature at all heights of the anode body remains stable. Compared to anodes in prebaked tanks with inconsistent morphology and performance, the overall performance is superior. This eliminates the need to replace the anodes inside the cell with new, pre-assembled electrodes from outside the cell. Instead, anode pellets are regularly replenished, entering the device from the upper side of the anode housing and evenly deposited on the anode body via the anode pellet distribution plate, ensuring the overall anode height. This effectively addresses the current issue of electrode replacement in large prebaked anode aluminum electrolytic cells, reducing the impact of electrode replacement on the cell, the resulting environmental pollution, and the significant workload. Furthermore, since the iron-carbon and aluminum-iron contact voltage drops of prebaked anode conductors are eliminated, the overall anode conductor pressure is lower than that of prebaked anode conductors. Four grooves of uniform depth within the anode facilitate better gas removal, allowing for a lower inter-electrode distance during production.

[0011] The new, highly efficient, environmentally friendly aluminum electrolytic cell incorporates an electrolytic cell asphalt fume purification device. This device consists of two main pipes of varying diameters, each constructed from galvanized steel pipe with numerous bends. These pipes are symmetrically placed on support beams, allowing the asphalt fume within to be fully heated before entering the electrolyte. The upper portion of the device is an assembly of conventional steel pipes and flexible hoses, one end of which connects to a threaded connector on the edge insulation panel and the other to the upper exhaust port on the outside of each anode box. The lower portion of the device, which extends into the high-temperature electrolyte, utilizes a high-temperature-resistant silicon nitride-bonded silicon carbide tube. Threaded connections are used between the various pipes and the metal casing of the asphalt fume purification device. Asphalt fumes generated from the anodes enter the asphalt purification unit through the exhaust holes on the top of each anode box. After being fully preheated through the unit's long, curved pipes and lower pipes, they enter the electrolyte liquid at approximately 960°C, where they undergo thorough cracking and decomposition. The asphalt fumes then escape into the electrolyte liquid, encountering oxygen introduced through the central insulating cover and the pipes above the gas collection feed box on the surface of the hot electrolyte liquid, where they combust and become harmless gases. This effectively solves the problem of asphalt fume control within the electrolytic cell, effectively purifying the generated asphalt fume and meeting environmental requirements.

[0012] The new, highly efficient and environmentally friendly aluminum cell features a specialized electrolytic cell insulation cover and gas collection box, sealing the high-temperature electrolyte and anode within a small, high-temperature chamber. This changes the century-old practice of using alumina for insulation and sealing. The sealing performance of the alumina electrolyte mixture is generally poor, with localized gaps. The high thermal conductivity of alumina powder, approaching 10W / m·K, makes it less than ideal for sealing and insulating the flue gas. Furthermore, the large space formed by the closed cell door cover, where the discharge hole and flame hole are completely open, results in significant heat loss from the upper portion, reaching 55%. The thermal conductivity of the cover material is very low. The thermal conductivity of high-temperature calcium silicate board is only 0.034W / m·K at room temperature, and only about 0.1W / m·K at a high temperature of 600°C. The thermal insulation effect is much better than that of the alumina electrolyte mixture. Moreover, it is completely enclosed. The cover material has no gaps. Only the discharge gas collecting box serves as the inlet and outlet of alumina and flue gas. Therefore, very little heat is dissipated from the top. This part of heat can effectively roast the numerous anodes in the tank and also lay the foundation for reducing the tank voltage. At the same time, the gas generated during the production process is sealed in a small, high-temperature space and directly enters the gas collecting discharge box without leakage, which greatly improves the environment around the tank and the factory building. The entire high-temperature electrolyte liquid is clean and smooth. In the later stage of electrolytic cell startup, after the electrolytic cell furnace and legs are naturally formed, the tank chamber of the entire tank is also regular and stable. In this way, alumina is evenly spread from the gas collection box onto the surface of the electrolyte. Because the electrolyte is clean and smooth, the alumina quickly dissolves and diffuses throughout the tank, allowing the alumina concentration in the electrolyte of the entire tank to be maintained stably, such as at around 3%. The electrolyte can effectively wet the anode, and the electrolysis efficiency can be greatly improved. At the same time, when the alumina is evenly spread from the gas collection box, it adsorbs harmful gases such as HF in the flue gas. After the flue gas is treated by the purification system outside the factory, the discharged flue gas is more environmentally friendly. This effectively solves the problems of dirty electrolyte, irregular furnace, and poor electrolyte flow that have always existed in current large-scale pre-baked anode cells and all previous electrolytic cells, including self-baking cells, as well as the problem of excessive heat dissipation from the upper part of the electrolytic cell, which causes flue gas and dust to pollute the production site environment.

[0013] The following benefits can be achieved by using the present invention to transform existing large prebaked cells or to build new large aluminum electrolytic cells:

[0014] The invention can save a lot of investment in processes such as baking pre-baked anodes, assembling anodes, exchanging anodes, and cleaning butts; it also makes production more stable and controllable; the production site and its surroundings are cleaner and more environmentally friendly; and because the original dirty, tiring, and dangerous workstations such as anode assembly, anode replacement, and butt cleaning are no longer necessary, production is safer. By applying the invention, the current efficiency will be increased by 1-4%, and the cell voltage will be reduced by 100-300 mV. By applying the invention, enterprises can reduce production costs by approximately RMB 1,200 / TAL.

[0015] Figure 1 This is a structural diagram of a new type of high-efficiency and environmentally friendly aluminum electrolytic cell. Figure 2This is the main view of the electrolytic cell beam. Figure 3 is the anode side view, Figure 4 This is the cross-sectional structure diagram of the anode bottom. Figure 5 This is the side view of the anode branch busbar. Figure 6 is a side view of the conductive tape unit, Figure 7 This is a top view of the main body of the aluminum electrolytic cell asphalt purification device. Figure 8 This is the structure diagram of the thermal insulation cover plate on the edge of the electrolytic cell

[0016] Figure 9 This is the main view of the thermal insulation cover in the electrolytic cell. Figure 10 This is a three-view drawing of the electrolytic cell gas collecting and discharging box.

[0017] Figure 1 In the figure, 1-aluminum liquid 2-high temperature electrolyte liquid 10-extension leg 3-electrolytic cell support beam 41-anode box 42-isolation cloth 43-metal box 44-isolation cloth inlet 45-anode particle distribution plate 46-anode particle entry device 47-pneumatic clamping device 51-anode cone 52-liquid anode paste 53-anode particles 54-anode groove 61-anode branch bus 62-conductive belt 71-asphalt smoke purification device body 72-asphalt smoke upper pipe 73-asphalt smoke lower pipe 81-electrolytic cell side insulation cover 82-electrolytic cell middle insulation cover 9-electrolytic cell gas collecting and feeding box. DETAILED DESCRIPTION

[0018] The novel high-efficiency and environmentally friendly aluminum electrolytic cell of the present invention effectively solves and overcomes the long-standing defects and shortcomings of aluminum electrolytic cells. In order to facilitate understanding of the structure and production operation of the novel high-efficiency and environmentally friendly aluminum electrolytic cell, it is described below with reference to the accompanying drawings and embodiments.

[0019] Before commissioning, N / 2+1 support beams (3) are installed and fixed on the edge of the electrolytic cell. The main body (71) of the aluminum electrolytic cell asphalt fume purification device is installed on the support beams (3) and the lower smoke pipe (73) is connected. At the same time, the middle heat insulation cover (82) and the gas collection feed box (9) are placed in the center of the support beam (3). The feed port connector (92) of the gas collection feed box is connected to the alumina feed box, and the smoke pipe (96) connector is connected to the electrolytic cell smoke pipe. Then all anode boxes (4) are installed on the support beams, and the anodes (5) cast and baked outside the cell are hoisted into the anode box. The anodes are fixed to the anode aluminum busbar by aluminum conductors (6). After the electrolytic cell is started, the edge heat insulation cover (81) is covered, and the upper asphalt smoke pipe (72) of the asphalt fume purification device is connected to the asphalt fume purification device main body (71) and the anode box smoke exhaust hole.

[0020] The present invention is specially designed to manufacture an electrolytic cell heat insulation cover plate (8), comprising a middle heat insulation cover plate (82) and a side heat insulation cover plate (81), wherein the outer structure of the side heat insulation cover plate (81) is different due to the different parts of the electrolytic cell where it is located. Figure 8 This is the structural diagram of the most important edge insulation cover plate, which has a threaded hole for connecting the asphalt smoke pipe. The edge insulation cover plate (81) is composed of steel plate (811), high-temperature calcium silicate plate (812), and ceramic fireproof cloth (813). The middle electrolytic cell insulation cover plate (82) is composed of steel plate (821), high-temperature calcium silicate plate (822), ceramic fireproof cloth (823) and two air pipes (824) made of high-temperature resistant silicon nitride combined with silicon carbide tubes or corundum tubes. The function of the air pipe is to introduce external oxygen to burn, crack, and pyrolyze the asphalt smoke and CO. Before production, the middle insulation cover plate (82) and the gas collection feed box (9) are placed in the middle of the support beam (3). After the electrolytic cell is started, the edge insulation cover plate (81) is covered. During production, the heat, gas, and dust generated are completely sealed in a sealed chamber formed by the electrolytic cell thermal insulation cover (8), the electrolytic cell beam (3), the anode box (4), the anode (5), and the electrolytic cell tank edge plate (1). The upper part of the sealed chamber is slightly higher than the top of the asphalt fume purification device body, and the bottom is the high-temperature electrolyte liquid level. In this way, the flue gas of the electrolytic cell will not escape through the feed port, the flame eye, and the alumina cover material like the original electrolytic cell, and will be spread and filled into the large space surrounded by the cell door cover and the upper facilities of the electrolytic cell, and will be collected into the gas collection cover under the action of negative pressure. Instead, it will directly enter the gas collection feed box in the sealed chamber. The thermal conductivity of the electrolytic cell thermal insulation cover material is much lower than that of alumina, and the structure is dense and airtight, which greatly reduces the heat loss of the electrolytic cell and the leakage of flue gas and dust, and greatly improves the environment around the cell and the factory building.

[0021] The present invention specifically provides an aluminum electrolytic cell asphalt fume purification device (7), which consists of an asphalt purification device body (71), an upper asphalt fume pipe (72), and a lower asphalt fume pipe (73). The asphalt purification device body (71) is made of a galvanized steel pipe processed into a pipe with many bends and is symmetrically placed flat on a support beam. The upper asphalt fume pipe (72) of the device is an assembly of an ordinary steel pipe and a hose connected together. The lower asphalt fume pipe (73) of the device is a high-temperature resistant silicon nitride-bonded silicon carbide pipe. Threaded connections are used between the various pipes of the asphalt fume purification device and between the asphalt fume purification device and the metal shell. Before production, the asphalt fume purification device body (71) is installed on the support beam (3) and the lower asphalt fume pipe (73) is connected. After the electrolytic cell is started, the edge insulation cover (81) is covered, and the upper fume pipe (72) of the asphalt fume purification device is connected to the asphalt fume purification device body (71) and the anode box exhaust hole through the edge insulation cover (81) and the threaded joint on the anode box. During the production process, the asphalt smoke generated on the upper part of the anode enters the upper smoke pipe (72) of the asphalt smoke purification device through the smoke exhaust holes on the upper part of each anode box, and then enters the asphalt purification device body (71). The asphalt purification device body is enclosed in a high-temperature, enclosed space and is formed by a long pipe with many bends. This allows the smoke to be fully preheated. The smoke then enters the electrolyte liquid at a temperature of about 960°C through the lower smoke pipe (73). The asphalt smoke is fully cracked and pyrolyzed, and then escapes into the electrolyte liquid. On the surface of the high-temperature electrolyte liquid, it encounters oxygen introduced from the gas pipe (824) on the middle heat-insulating cover plate and burns, turning into harmless and environmentally friendly gas. This effectively solves the problem of asphalt smoke treatment. The asphalt smoke generated during the production process is promptly and effectively purified in the electrolytic cell, meeting environmental protection requirements.

[0022] The present invention is specially designed to have a gas collection feed box, which is composed of a box body (91), a feed pipe (92) with a threaded joint, a first-level distribution plate (93), a second-level distribution plate (94), a smoking pipe (95), a sealing steel plate (96), a high-temperature calcium silicate plate (97), a ceramic fireproof cloth (98) and two intake pipes (99) connected by a steel pipe and a high-temperature resistant silicon nitride combined with silicon carbide tube or a corundum tube. The function of the intake pipe is to introduce external oxygen to burn CO, etc. Before production begins, the gas collection feed box, which has already been installed with a smoke pipe, a first-stage material distribution plate, a second-stage material distribution plate, a high-temperature calcium silicate board, and a ceramic fireproof cloth, is installed with the air intake pipe and placed on the main beam. It is close to the adjacent middle thermal insulation cover plate, leaving no gaps. The top positive feed pipe (92) is continuously connected to the discharge port of the alumina material box. The smoke pipe (95) with a threaded joint on the upper side of the box is connected to the electrolytic cell's smoke pipe, and the smoke pipe is connected to the factory's smoke pipe. During production, the material from the alumina material box passes through the feed pipe through the two-stage material distribution plate and floats downward relatively evenly. On the way, the alumina meets the flue gas, absorbs harmful components such as HF in the flue gas, and falls into the electrolyte liquid surface. Because the electrolyte is clean and smooth, the alumina quickly dissolves and diffuses throughout the tank, without forming sediment at the bottom of the furnace. The alumina concentration in the electrolyte of the entire tank is maintained stably (about 3%), the electrolyte can better wet the anode, and the electrolysis efficiency is also improved. During the later stages of electrolytic cell startup, after the cell furnace and legs have naturally formed, the entire cell chamber is perfectly regular and stable. Compared to the shell-breaking and unloading systems previously installed in prebaked anode electrolytic cells, the shell-breaking portion has been eliminated, leaving the unloading system in place. The capacity of the constant-volume unloader has been reduced (to 0.5 kg or less), simplifying unloading control. During production, flue gas flows upward and mixes with the downward-moving alumina. Harmful components like HF are adsorbed, resulting in a more environmentally friendly flue gas. This flue gas is then discharged from the box smoke pipe (into the cell branch pipe) and then, after passing through an off-site purification system, is discharged into the atmosphere. This exhaust gas is more environmentally friendly than that of previous large prebaked cells.

[0023] During the production process, the numerous anodes (5) participating in the electrolytic reaction are consumed in the reaction. At the same time, under the high temperature of the electrolyte and the internal electric heat, a portion of the anode solid layer (53) is simultaneously melted into a liquid paste (52), and a portion of the liquid paste is sintered into an anode cone (51). In electrolytic production, the anode consumption rate is about 2 mm per day (the electrolytic cells of each enterprise vary slightly). It is sufficient to add anodes once a day. The total amount is at most the difference of about 20 mm thick anode particles preheated on the upper part of the insulation. It will not affect the formation of the anode cone (51) and other reaction processes, and production is stable. In order to add anode particles conveniently and quickly, an anode feeding device is provided, including an anode feeding box and multiple feeding cylinders. The feeding box has a capacity of about 2 tons (it can also be larger). The lower end is connected to multiple feeding cylinders. The capacity of the feeding cylinders is the amount of anode particles added to each anode box per day. When the electrolytic cell needs to be fed with anode pellets, the anode feeding device filled with material is hoisted to the cell by a crane, the feeding barrel is connected to the feeding device (46) on the multiple anode boxes on the cell, and the anode pellets are placed into the anode boxes.

[0024] During production, like large prebaked cells, high-efficiency and environmentally friendly aluminum electrolytic cells also require busbar lifting. Pneumatic clamping devices (47) are installed on the anode box. These pneumatic clamping devices consist of a cylinder and a clamping plate, which are fixed to the front and back of the conductive belt unit (62). During the busbar lifting operation, the cylinders at the corresponding positions are controlled by the air control box to move the corresponding two sets of longer conductive belt units (62) on each anode box toward the clamping plate for clamping. The other two sets of conductive belt units are removed from the anode branch busbar (61), and two conductive belt units are connected to each. These are then installed on the anode branch busbar. The anode busbar is then lifted to the corresponding position, and the clamp is released. The operation is completed. A busbar lifting clamp device similar to the busbar lifting frame of the pre-baked cell can also be set up. During operation, the clamp of the device is clamped to the corresponding two groups of longer conductive belt units (62) on each anode box. Next, the conductive units of the other two groups of conductors are removed from the anode branch busbar (61), and two conductive units are connected to each, and then installed on the anode branch busbar. Then, the anode busbar is lifted to the corresponding position, the clamp is released, and the busbar lifting clamp device is removed.

[0025] The present invention has been described in detail above with reference to the embodiments of the accompanying drawings. Obviously, the embodiments described are only a part of the embodiments of the present invention, not all of the embodiments. Certain details in the embodiments should not constitute a limitation of the present invention. The scope of protection of the present invention shall be defined by the scope of the appended claims. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts also fall within the scope of protection of the present invention.

Claims

1. A high-efficiency and environmentally friendly aluminum electrolytic cell, comprising an electrolytic cell support beam fixed to the cell edge plate, an anode box mounted on the support beam, an aluminum electrolytic cell asphalt fume purification device, an electrolytic cell heat-insulating cover plate, and an electrolytic cell gas collecting and feeding box, as well as an anode mounted in the anode box and an anode conductor connecting the anode to the positive aluminum busbar; The electrolytic cell support beam is installed on the electrolytic cell edge plate. The electrolytic cell support beam serves to place the anode box, asphalt fume purification device, gas collection feed box and the middle electrolytic cell heat insulation cover plate; The asphalt fume purification device of the aluminum electrolytic cell consists of an asphalt purification device body, an upper asphalt fume pipe, and a lower asphalt fume pipe. The asphalt purification device body is made of galvanized steel pipe processed into a pipe with many bends, which is symmetrically placed on the support beam. The upper asphalt fume pipe of the device is an assembly connected by an ordinary steel pipe and a hose, and the lower asphalt fume pipe of the device is a high-temperature resistant silicon nitride combined with silicon carbide tube. The asphalt fume generated on the upper part of the anode enters the upper fume pipe of the asphalt fume purification device from the exhaust hole on the upper part of each anode box and enters the asphalt purification device body. The asphalt purification device body is enclosed in a high-temperature enclosed space and is formed by a long pipe with many bends, so that the flue gas can be fully preheated, and then enter the high-temperature electrolyte liquid through the lower flue pipe. The asphalt fume is fully cracked and pyrolyzed, and then escapes from the electrolyte liquid. On the surface of the high-temperature electrolyte liquid, it encounters oxygen introduced from the air inlet pipe on the middle heat-insulating cover plate and burns, turning into harmless and environmentally friendly gas. The electrolytic cell thermal insulation cover includes a central thermal insulation cover and an edge thermal insulation cover. The central thermal insulation cover includes two air inlet pipes. The function of the air inlet pipes is to introduce external oxygen to burn, crack, and pyrolyze asphalt smoke and CO. The central thermal insulation cover and the gas collecting feed box are placed in the middle of the supporting beam. The heat, gas, and dust generated are completely sealed in the sealed chamber formed by the electrolytic cell thermal insulation cover and the electrolytic cell beam, anode box, anode, and electrolytic cell groove plate. The upper part of the sealed chamber space is slightly higher than the top position of the asphalt smoke purification device body, and the bottom is the high-temperature electrolyte liquid level.

2. The high-efficiency and environmentally friendly aluminum electrolytic cell according to claim 1, characterized in that: The anode box is a rectangular block with an open bottom. The steel plate on the top of the anode box is welded firmly. Four slits are opened on the steel plate to allow the anode conductive belt to enter the box and connect to the anode. An anode particle entry device is set on the upper outer wall of the side of the box. An anode particle distribution plate is built in to allow the anode particles to fall more evenly on the top of the anode body. A circular hole is welded with a threaded pipe joint, which is connected to the asphalt fume purification device. A metal box for isolation cloth and an isolation cloth inlet are set further down. The isolation cloth is close to the inner wall of the box to separate the anode from the box without sticking together. A pneumatic clamping device is also set on the anode box, which consists of a cylinder and a clamping plate and is used when lifting the busbar.

3. The high-efficiency and environmentally friendly aluminum electrolysis cell according to claim 1, characterized in that: The anode is cast and baked outside the tank before it is put into production. When the anode is baked, part of the aluminum conductor below the height of the solid aluminum molten zone of the anode cone melts and flows away, naturally forming four grooves. During production, the four grooves with the same depth are well maintained inside the anode. The solid aluminum conductor in the upper part not only conducts current into the anode, but also firmly suspends the anode and moves up and down with the anode busbar.

4. The high-efficiency and environmentally friendly aluminum electrolysis cell according to claim 1, characterized in that: The conductor connecting the anode and the anode aluminum busbar is made of thick aluminum plate and aluminum soft strip. Among them, the anode branch busbar made of thick aluminum plate is symmetrically welded or fastened with screws on both sides of the anode aluminum busbar. The conductive strip unit is welded by aluminum soft strip and "7"-shaped aluminum blocks at both ends. In this way, the conductive strip units can be connected by snapping. Then, the top conductive strip unit is snapped onto the anode branch busbar to form a complete conductor. During the process of lifting the anode busbar, the conductive strip unit snapped onto the anode branch busbar is removed, and the new conductive strip unit is snapped on and then snapped onto the anode branch busbar.

5. The high-efficiency and environmentally friendly aluminum electrolysis cell according to claim 1, characterized in that: A gas collecting feed box is provided which is installed on the support beam and connects the smoke exhaust branch pipe and the alumina material box. It includes a box body, a feed pipe with a threaded joint, a first-level distribution plate, a second-level distribution plate, a smoking pipe and two air intake pipes. The function of the air intake pipe is to introduce external oxygen for combustion. The feed pipe is connected to the discharge port of the alumina material box, and the smoke exhaust pipe is connected to the smoke branch pipe of the electrolytic cell.

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