Continuous anode assembly, method of manufacture and aluminium electrolytic cell

Abstract

This application belongs to the field of aluminum electrolysis technology and discloses a continuous anode assembly, its preparation method, and an aluminum electrolysis cell. The continuous anode assembly includes a metal frame, a prebaked anode, anode paste, and a conductor. The metal frame has a channel open at both ends. The prebaked anode is fitted inside the channel of the metal frame and extends out of the metal frame. The prebaked anode located within the channel has at least one slot. The anode paste fills the metal frame and contacts at least one surface of the prebaked anode. The space containing the anode paste communicates with at least one slot. The conductor is disposed within the slot and / or the anode paste, and is connected to the metal frame. The volume of the slot is larger than the volume of the conductor. The continuous anode assembly of this application features structural stability, rapid current rise, and uniform current distribution during use.

Description

Technical Field

[0001] This application belongs to the field of aluminum electrolysis technology, specifically relating to continuous anode components, preparation methods, and aluminum electrolysis cells. Background Technology

[0002] With the ever-increasing global demand for aluminum and its alloys, the aluminum electrolysis industry is facing unprecedented pressure: how to improve production efficiency while effectively reducing energy consumption and environmental pollution. As the core link in aluminum production, the efficiency and cost of the aluminum electrolysis process directly determine the competitiveness and sustainable development potential of the entire aluminum industry. In the aluminum electrolysis cell, the anode, as a key component that conducts current and participates in the electrochemical reaction, has a crucial impact on the cell's operating efficiency and production costs. To meet the stringent requirements of aluminum electrolysis cells for anodes, especially their ability to conduct current and participate in electrochemical reactions, the anodes used in continuous anode aluminum electrolysis cells must possess low resistivity (not higher than 80 μΩ·m) and high compressive strength (not less than 27 MPa).

[0003] Currently, continuous anodes are typically prepared using non-conductive, loose, blocky anode paste as raw material. This anode paste, made by mixing binders and carbon materials through a specific process, cannot be used directly as an anode and requires a series of complex equipment and processes for transformation. Specifically, the first step involves high-temperature heating, melting, and molding to transform the anode paste into a prototype of a continuous anode; the second step involves calcination and carbonization of the prototype, completely transforming the anode paste into a carbonized body, which then becomes an anode with good conductivity, high strength, and meets the requirements of electrolysis. In the process of transforming the anode paste into a prototype of a continuous anode, existing technologies mainly employ two methods: in-tank casting calcination and out-of-tank casting calcination.

[0004] The in-cell casting and roasting method is a process in which the anode paste is directly cast and roasted within the electrolytic cell. This method uses an electrochemical paste furnace to heat the anode paste to a certain temperature (e.g., around 100°C), melting it and allowing it to flow into the lower part of the anode frame to be cast into the desired shape. However, this method has several problems. First, the rapid heating, melting, and casting of the anode paste results in the release of large amounts of VOCs (volatile organic compounds), severely polluting the environment. Second, the high impact voltage during the series current roasting of the anode paste and the slow current rise rate (typically requiring about 72 hours to reach full current) severely impact other operating electrolytic cells. Furthermore, the slow conversion of the anode paste into the anode cone leads to continuous VOC emissions, creating a harsh environment and posing a serious pollution risk. Simultaneously, uneven current distribution during roasting can easily lead to problems such as red-hot rods and rod breakage, potentially causing anode failure and necessitating the shutdown of the electrolytic cell, posing a serious safety risk.

[0005] The external casting and baking method is a process of casting and pre-baking the anode paste outside the electrolytic cell. This method involves constructing a simple open baking furnace outside the electrolytic cell, placing the lower part of the anode frame inside the furnace, and filling the anode frame with anode paste. The heat generated in the furnace is used to heat, melt, cast, and pre-bake the anode paste at the bottom of the anode frame. However, this method also has many problems. First, although the impact voltage is reduced, the current rise rate is improved, and the current distribution is better, it does not completely solve the technical problems of high impact voltage, slow current rise rate, and uneven current distribution during the series current baking of the anode paste, posing serious safety risks. Second, the conversion rate of the anode paste into the anode cone is still slow, resulting in the volatilization of about 50% of the binder and the emission of a large amount of VOC fumes, which seriously pollute the environment and is difficult to treat, posing a serious pollution risk. Furthermore, this method also suffers from problems such as paste flow, anode cone oxidation, and cracking, affecting the quality and service life of the anode. Meanwhile, the yield of anode paste converted into anode cones is low, usually below 90%, which increases production costs and wastes resources.

[0006] In summary, existing continuous anode preparation technologies still have many shortcomings and problems, and there is an urgent need to develop new, efficient, and environmentally friendly continuous anodes and preparation processes. Summary of the Invention

[0007] In order to further reduce the high impact voltage during the baking of aluminum electrolytic cells, achieve the goal of rapidly increasing the current of the entire series and uniform anode current distribution, and at the same time solve the problems of slurry flow, large VOC flue gas, environmental pollution, anode cone oxidation and cracking that occur during the melting, casting, baking and conversion of anode paste into anode cones, this application aims to provide a continuous anode component, preparation method and aluminum electrolytic cell.

[0008] In one aspect of this application, a continuous anode assembly is provided, comprising: A metal frame with channels open at both ends; The prebaked anode is fitted inside the channel of the metal frame and extends out of the metal frame. The prebaked anode located in the channel has at least one slot. Anode paste, which is filled within a metal frame and in contact with at least one surface of a prebaked anode, wherein the space containing the anode paste is in communication with at least one slot; A conductor, which is assembled in at least one slot and / or in anodized paste; the conductor is connected to a metal frame.

[0009] In one embodiment, the slotting includes a first slot and a second slot, the first slot being in communication with the space where the anode paste is located; the second slot is used for assembling conductors.

[0010] In one embodiment, the bottom end of the prebaked anode extends out of the metal frame, the anode paste fills the metal frame at the top of the prebaked anode, and the conductor is assembled in the second slot and the anode paste; when the prebaked anode is in contact with the resistive layer, the bottom surface of the prebaked anode has an irregular shape.

[0011] In one embodiment, the continuous anode assembly includes at least two prebaked anodes, each prebaked anode contacting the inner wall of the channel and forming an anode cavity between the prebaked anodes, the anode paste filling the anode cavity, and a conductor assembled in a second slot.

[0012] In one embodiment, the prebaked anode is composed of at least one prebaked block, and the at least one prebaked block has slots.

[0013] In one embodiment, when there are two or more prebaked blocks, the prebaked blocks are connected by an intermediate medium to form a prebaked anode, or directly connected to form a prebaked anode; the intermediate medium includes a bonding paste that bonds the prebaked blocks together, or includes a material corroded by the electrolyte, including ceramic fiber board, cardboard or wood board; the material corroded by the electrolyte automatically forms grooves between the prebaked blocks, which is conducive to the discharge of anode gas.

[0014] In one implementation, the prebaked anode is replaced by a cathode carbon block.

[0015] In one embodiment, the prebaked anode has a bulk density of 1.56~1.81 g / cm³. 3 Its resistivity is 36~56 μΩ·m and its compressive strength is 32~56MPa.

[0016] In one embodiment, the adhesive paste includes any or any combination of carbon material, binder, aluminum-containing compound, cryolite, wood board, cardboard, and ceramic fiber board. The carbon material may contain biochar, and the aluminum-containing compound may be alumina or aluminum chloride.

[0017] In one embodiment, the anode paste includes a carbon material and a binder.

[0018] In one embodiment, the carbon material in the anode paste has a mass content of 71-79 wt%, and the binder has a mass content of 21-29 wt%.

[0019] In one embodiment, the carbon material is selected from one or more of petroleum coke, pitch coke, calcined petroleum coke, graphite, and biomass.

[0020] In one embodiment, the binder is selected from one or more of asphalt, resin, tar, white sugar, syrup, paraffin, aluminum hydrogen phosphate, rosin, ammonium persulfate, starch, lignin, and engine oil.

[0021] In one embodiment, the metal frame is made of aluminum or an aluminum alloy.

[0022] In one embodiment, one end of the conductor is provided with a protruding end, which is connected to the metal frame.

[0023] In one embodiment, the conductor is made of one or more of the following materials: metal, metal alloy, and cryolite.

[0024] In one embodiment, the material of the upturned head is selected from one or more of metal, metal alloy, and cryolite.

[0025] In one embodiment, one end of the conductor is connected to a baffle, which is connected to a metal frame.

[0026] In one embodiment, the baffle is made of one or more of graphite, ceramic, and graphene.

[0027] In one embodiment, the bottom surface of the continuous anode assembly is irregularly shaped, which can increase the surface area of ​​the bottom surface to increase the contact area and tightness with the resistive layer under the continuous anode assembly, or increase the surface area corresponding to the cathode with an irregularly shaped upper surface.

[0028] In one embodiment, when the bottom surface of the continuous anode assembly is irregularly shaped, it is provided with a plurality of protrusions and / or recesses, including a plurality of V-shaped, arched, roof-shaped or semi-cylindrical protrusions and / or recesses.

[0029] In one embodiment, when the upper surface of the cathode is irregularly shaped, the bottom surface of the continuous anode assembly is also irregularly shaped and matches the upper surface shape of the cathode.

[0030] In another aspect of this application, a method for preparing a continuous anode assembly is provided, comprising: A prebaked anode with at least one slot is prefabricated, and a conductor is placed in at least one slot; The prebaked anode with slotted areas is fitted into a metal frame, so that the conductor is connected to the metal frame, and part of the prebaked anode extends out of the metal frame; Anode paste is filled at least one surface of the prebaked anode within a metal frame, or a conductor is laid within a metal frame and anode paste is filled at at least one surface of the prebaked anode; the space containing the anode paste is in communication with at least one slot.

[0031] In one embodiment, the prebaked anode is formed by connecting at least one prebaked block, and the at least one prebaked block has a slot; when the prebaked anode is in contact with the resistive layer, the bottom surface of the prebaked anode has an irregular shape.

[0032] In one implementation, multiple prebaked blocks are connected by an adhesive paste.

[0033] In one implementation, the prebaked anode is replaced by a cathode carbon block.

[0034] In one embodiment, one end of the conductor is provided with a protruding end, which is connected to the metal frame.

[0035] In one embodiment, the conductor is made of one or more of the following materials: metal, metal alloy, and cryolite.

[0036] In one embodiment, the material of the upturned head is selected from one or more of metal, metal alloy, and cryolite.

[0037] In one embodiment, one end of the conductor is connected to a baffle, which is connected to a metal frame.

[0038] In one embodiment, the baffle is made of one or more of graphite, ceramic, and graphene.

[0039] In another aspect of this application, an aluminum electrolytic cell includes: an electrolytic cell body; a cathode disposed at the bottom of the electrolytic cell body; and a continuous anode assembly mounted on the electrolytic cell body, wherein the continuous anode assembly and the cathode form an electrical connection path through a resistive layer, or form an electrical connection path through an electrolyte and / or liquid aluminum.

[0040] In one embodiment, a continuous anode assembly includes a metal frame, a prebaked anode, an anode paste, and a conductor. The metal frame has a channel open at both ends. The prebaked anode is fitted inside the channel of the metal frame and extends out of the metal frame. The prebaked anode located in the channel has at least one slot. The anode paste fills the metal frame and contacts at least one surface of the prebaked anode. The space where the anode paste is located communicates with at least one slot. The conductor is assembled in at least one slot and / or in the anode paste. The conductor is connected to the metal frame.

[0041] In one embodiment, the aluminum electrolytic cell further includes a resistive layer; the resistive layer is located between the continuous anode assembly and the cathode, and is in contact with the continuous anode assembly and the cathode.

[0042] In one implementation, when the resistive layer is in contact with the continuous anode assembly, the bottom surface of the continuous anode assembly has an irregular shape.

[0043] In one embodiment, the resistive layer is made of one or more of carbon materials, graphite, biochar, and metallic aluminum.

[0044] In one implementation, after the prebaked anode is completely consumed, the carbonized body converted from the anode paste replaces the prebaked anode.

[0045] In one embodiment, the bottom surface of the carbonized body has an irregular shape.

[0046] The beneficial effects of this application are as follows: 1. By using a prebaked anode with high conductivity and high strength to replace the non-conductive, bulk anode paste in the continuous anode, the casting and baking steps inside or outside the continuous anode tank are eliminated, significantly shortening the process flow.

[0047] 2. The use of highly conductive prebaked anodes reduces the impulse voltage, resulting in a more uniform anode current distribution and improved electrolytic cell stability. Simultaneously, it reduces or effectively avoids the emission of volatile organic compounds (VOCs), meeting environmentally friendly production requirements. It enables rapid current ramp-up across the entire series, preventing adverse effects on other aluminum electrolytic cells and ensuring production continuity and stability. The continuous anode assembly employs coke granule roasting and high-temperature inert gas roasting methods during the roasting process, resulting in low impulse voltage, rapid full current ramp-up, and uniform current distribution. It eliminates the need for rapid anode paste conversion to anode cones, avoiding the safety and pollution issues that can easily occur during this conversion.

[0048] 3. The heating, melting, casting, and pre-baking of the anode paste are achieved using the heat energy of the prebaked anode itself, effectively saving energy. When the anode paste is heated to the point of melting and generates a large amount of VOC flue gas, the metal frame around the continuous anode remains intact, effectively preventing the leakage of paste and VOC flue gas. The VOC value escaping from the upper opening of the metal frame is lower than the relevant national standards, further demonstrating the environmental advantages of this invention.

[0049] 4. The prebaked anode is located below the anode paste, which raises the position of the heating, melting, casting, and prebaking of the anode paste, and slows down these processes. This allows the anode paste to penetrate the prebaked anode better, strengthens the bond between the anode paste and the prebaked anode, and improves the overall structural stability.

[0050] 5. The prebaked anode temperature is gradually increased by utilizing the resistance heat generated when a series of currents pass through it or the heat energy carried by high-temperature inert gas. This process gradually heats, melts, and casts the anode paste, followed by prebaking. When the series of currents passes through the metal frame and conductor into the anode paste, it undergoes further calcination until it transforms into a carbonized body with good conductivity and high strength. This improves the quality of the anode paste carbonized body and enhances its durability and stability during use.

[0051] 6. Under the multiple protections of the prebaked anode, metal frame, and anode paste, the carbonized body did not exhibit oxidation or cracking issues. This ensures the integrity and performance stability of the anode, enables continuous anode operation, improves the working environment, and achieves a high degree of automation.

[0052] 7. The bottom surface of the continuous anode assembly has an irregular shape, which can increase the contact area, tightness and uniformity between the anode and the underlying resistive layer, which is beneficial to improving the uniformity of the anode current distribution and reducing the impact voltage during calcination. Attached Figure Description

[0053] Figure 1 This is a schematic diagram of the continuous anode assembly in Embodiment 1 of this application; Figure 2 This application Figure 1 Side view; Figure 3 This application Figure 1 Top view; Figure 4 This is a schematic diagram of the continuous anode assembly in Embodiment 2 of this application; Figure 5 This is a schematic diagram of the continuous anode assembly in Embodiment 3 of this application.

[0054] In the picture: 1-Metal frame, 11-Electrification surface, 12-Electrification surface; 2-Prebaked anode, 21-First slot, 22-Second slot, 23-Prebaked block, 24-Protrusion, 25-Depression; 3-Anode paste; 4-Conductor, 41-Upturned head, 42-Baffle; 5-Anode guide rod; 6-Intermediate medium; 7-Calcinated petroleum coke particles. Detailed Implementation

[0055] The present application will be further described in detail below with reference to the accompanying drawings, wherein the same numbers in all the drawings denote the same features. Although specific embodiments of the present application are shown in the drawings, it should be understood that the present application can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this application will be thorough and complete, and will fully convey the scope of the present application to those skilled in the art.

[0056] Self-baking anodes are a type of anode that can be used continuously without replacement (but requires periodic replenishment). They rely on the heat generated during electrolysis to bake the anode paste, forming a dense, monolithic solid anode. Their advantages include a short anode paste production process, low cost, reduced investment, and scalable production. However, they also have disadvantages, such as significant environmental impact and pollution risks when used in electrolytic cells, harsh working conditions, increased anode voltage drop leading to high power consumption, and hindering the mechanization and automation of electrolysis production. They require manual periodic insertion and removal of conductive rods, manual lifting of the anode frame and transfer busbars, and the use of coke particles to bake self-baking anodes poses significant safety risks; furthermore, high-temperature inert gas baking of self-baking anodes is prohibited. With the development of aluminum electrolysis technology, prebaked anodes have gradually replaced self-baking anodes as the mainstream. Prebaked anodes are anode carbon blocks pre-baked in the factory, possessing advantages such as high mechanical strength, low resistivity, and good conductivity. The use of prebaked anodes improves the current efficiency of electrolytic cells, reduces energy consumption, and facilitates the mechanization and automation of electrolysis production. However, the process of prebaked anodes is long and the production cost is relatively high. Before being used in an electrolytic cell, the prebaked anode must be connected to the anode rod by pouring high-temperature liquid pig iron phosphate. It also requires manual replacement periodically. The working environment during replacement is harsh and the labor intensity is high, which affects the stable and efficient operation of the electrolytic cell. It cannot be automated, which increases the downtime and production cost of the electrolytic cell.

[0057] To address this, the applicant proposes a technical solution combining self-baking anodes and prebaked anodes. In the electrolytic cell, current heating raises the temperature of the prebaked anode, which in turn pre-baks the anode paste. As the electrolytic cell transitions from the baking and start-up stages to normal operation, the prebaked anode is gradually consumed, and the anode paste transitions from pre-baking to formal baking, gradually transforming into a carbonized body with a resistivity of less than 70 μΩ·m, a mechanical strength greater than 30 MPa, and fused with the top surface of the prebaked anode. This process results in low impact voltage, uniform anode current distribution, avoids impacting other operating electrolytic cells, and achieves a high degree of automation. Simultaneously, the emitted VOC value is low, making it environmentally friendly.

[0058] In one embodiment of this application, reference is made to Figures 1-4 A continuous anode assembly is provided, comprising: a metal frame 1, a prebaked anode 2, an anode paste 3, and a conductor 4. The metal frame 1 has a channel with openings at both ends. The prebaked anode 2 is fitted inside the channel of the metal frame 1 and extends out of the metal frame 1. The prebaked anode 2 located in the channel has at least one slot. The anode paste 3 fills the metal frame 1 and contacts at least one surface of the prebaked anode 2. The space where the anode paste 3 is located communicates with at least one of the slots. The conductor 4 is assembled in at least one of the slots, or the conductor 4 is assembled in at least one of the slots and in the anode paste 3. The conductor 4 is connected to the metal frame 1.

[0059] Compared to existing methods that directly self-bake anode paste 3, this continuous anode assembly exhibits lower impact voltage, faster current rise, and more uniform current distribution during the series current baking of anode paste 3. This is mainly due to the poor conductivity of anode paste 3. Anode paste 3 is non-conductive at room temperature. When the anode paste 3 is heated from room temperature to 120°C or above, it begins to soften, deform, melt, and flow. When the anode paste 3 is heated to around 320°C, the binder decomposes, releasing a large amount of VOCs, and it gradually transforms into an anode cone, becoming conductive, although its resistivity is greater than 2500 μΩ·m. This application utilizes the good conductivity of the prebaked anode 2 (resistivity less than 56 μΩ·m at room temperature, which decreases with increasing temperature). When a series of currents are conducted into the continuous anode and then into the prebaked anode 2, the anode paste 3 is prebaked by the resistance heat generated by the prebaked anode 2. When the electrolytic cell transitions from the roasting and start-up stages to the normal operation stage, the prebaked anode 2 is gradually consumed, and the anode paste 3 on it transitions from prebaking to formal roasting. At this time, the anode paste 3 gradually transforms into a carbonized body with a resistivity of less than 70 μΩ·m and a mechanical strength of greater than 30 MPa, which is integrated with the top surface of the prebaked anode 2. Therefore, the uniform distribution of current in the anode and the cell voltage can be well controlled.

[0060] Meanwhile, the applicant discovered that existing direct self-baking technology for anode paste 3 avoids connection problems because the interface between the anode paste 3 and the added anode paste 3 is constantly flowing during the formation of the anode cone. However, in the technical solution of this application, due to the smooth and dense surface of the prebaked anode 2, the anode cone formed by the carbonization of the anode paste 3 exhibits shrinkage characteristics, resulting in weak adhesion between the anode cone and the prebaked anode 2. Therefore, this application creates grooves on the prebaked anode 2. On one hand, as the pores in the grooves enlarge due to heat, excess binder penetrates into the pores and surfaces of the grooves. During the carbonization of the binder, the carbonized body is firmly adhered to the prebaked anode 2, while simultaneously preventing the flow of binder from the anode assembly when the binder content in the anode paste 3 is high. On the other hand, when the anode paste 3 is heated to melt and generates VOCs, the grooved portion can accommodate the generated VOC gas. The VOCs penetrate into the prebaked anode 2 and undergo secondary thermal decomposition on the inner wall of the pores of the prebaked anode 2, further improving the conductivity and mechanical strength of the prebaked anode 2.

[0061] In this application, the metal frame 1 serves as a peripheral component of the continuous anode, providing a reliable housing space for the prebaked anode 2 and the anode paste 3. The metal frame 1 has one or more channels open at both ends, which are used to accommodate and connect other components, such as the prebaked anode 2. The shape, size, structure, and channel configuration of the metal frame 1 can be designed according to specific application requirements to ensure compatibility with the prebaked anode 2 and other components. The metal frame 1 is made of metallic materials that possess good electrical conductivity, mechanical strength, and corrosion resistance to ensure stable current transfer during electrolysis, resist electrolyte corrosion, improve binder coking value, prevent VOC emissions into the surrounding environment, and melt and flow to the cathode upon contact with the electrolyte. It is understood that the metal frame 1 encompasses all metal components possessing the aforementioned structural, material, and functional characteristics, regardless of their specific shape, size, or manufacturing process.

[0062] In some embodiments, the two sides of the channel of the metal frame 1 are respectively designated as an input surface 11 and an output surface 12. The prebaked anode 2 cooperates with the metal frame 1, wherein one side of the prebaked anode 2 forms electrical contact with the input surface 11 of the metal frame 1, and the other side forms electrical contact with the output surface 12. The input surface 11 serves as the current input terminal, receiving current from an external power source, while the output surface 12 serves as the other current input terminal, transmitting current to the conductor 4 and the prebaked anode 2, completing the energy transfer process. The shape and size of the prebaked anode 2 are adapted to the channel of the metal frame 1 so that it can be tightly inserted into the channel.

[0063] In some embodiments, at least one anode guide rod 5 is provided on the outer surface of the metal frame 1. This anode guide rod 5 is electrically connected to the anode busbar of the electrolytic cell, used to transmit electrical energy supplied by an external power source into the electrolytic cell to realize the electrolytic reaction. The number of anode guide rods 5 is determined by the size of the continuous anode, and can be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, etc. Preferably, there are 6 anode guide rods 5, which are movably connected to the inlet surface 11 and outlet surface 12 of the metal frame 1, respectively. Current flows through the anode guide rods 5 from the inlet surface 11 and outlet surface 12 into the prebaked anode 2. After conduction inside the prebaked anode 2, it flows out from the cathode and into the inlet end of the next aluminum electrolytic cell, thus realizing the conduction of a series of currents.

[0064] In some embodiments, the anode guide rod 5 can be made of a highly conductive and high-strength material, such as copper, aluminum, or aluminum alloy, to ensure low-impedance current transmission, clamping and suspending the continuous anode assembly above the cathode. The anode guide rod 5 can be columnar, rod-shaped, or other shapes suitable for connection to the anode busbar and metal frame 1, with its inner and / or sides movably connected (e.g., pressed) to the metal frame 1. Simultaneously, the anode guide rod 5 is connected to the anode busbar of the electrolytic cell, and the connection method can be welding, clamping, flexible strip connection, bolt connection, etc., to ensure the stability and reliability of the electrical connection. The anode guide rod 5 is connected to an anode lifting machine to control the lifting and lowering of the continuous anode assembly and the cell voltage, as well as to independently lift the anode guide rod 5 to prevent corrosion by the liquid electrolyte.

[0065] In some embodiments, the connection position of the anode rod 5 to the metal frame 1 is specifically selected at or near the position corresponding to the prebaked anode 2 to ensure that the current can be directly and effectively transmitted to the prebaked anode 2.

[0066] In some embodiments, the metal frame 1 is made of aluminum or aluminum alloy. Aluminum and aluminum alloys have a low density, which helps to reduce the overall weight of the anode assembly. They also have good electrical conductivity and mechanical strength, which can meet the high-performance requirements of the anode assembly during the electrolysis process and does not contaminate the product quality of the electrolytic cell.

[0067] In this application, the prebaked anode 2 is a key electrode material used in the aluminum electrolysis process. It is made from carbon aggregates such as petroleum coke, pitch coke, and biochar, and binders such as coal tar pitch, through processes including high-temperature calcination, crushing, screening, batching, kneading, molding, and calcination. It possesses a stable geometric shape and good electrical conductivity and mechanical properties, enabling it to operate stably in the high-temperature, high-voltage, and highly corrosive aluminum electrolysis environment. The prebaked anode 2 typically has a regular geometric shape, such as rectangular or circular, to meet the structural requirements of continuous anode assemblies. The dimensions of the prebaked anode 2 (such as length, width, and height) should be determined according to the design requirements of the electrolytic cell and the electrolysis process conditions.

[0068] In some embodiments, the raw materials for the prebaked anode 2 include carbon material and a binder, wherein the carbon material accounts for 83.5-85 wt% by mass and the binder accounts for 15-16.5 wt% by mass. For example, the carbon material accounts for 83.5 wt%, 84.0 wt%, 84.5 wt%, or 85.0 wt% by mass, and the binder accounts for 15.0 wt%, 15.2 wt%, 15.4 wt%, 15.6 wt%, 15.8 wt%, 16.0 wt%, 16.2 wt%, 16.4 wt%, or 16.5 wt% by mass.

[0069] In some embodiments, the prebaked anode 2 has a bulk density of 1.56~1.81 g / cm³.3 Its resistivity is 36~56 μΩ·m, and its compressive strength is 32~56 MPa. For example, its bulk density is 1.56 g / cm³. 3 1.61 g / cm 3 1.66 g / cm 3 1.71g / cm 3 1.76 g / cm 3 Or 1.81 g / cm 3 The resistivity is 36 μΩ·m, 38 μΩ·m, 40 μΩ·m, 42 μΩ·m, 44 μΩ·m, 46 μΩ·m, 48 μΩ·m, 50 μΩ·m, 52 μΩ·m, 54 μΩ·m or 56 μΩ·m, and the compressive strength is 32MPa, 34MPa, 36MPa, 38MPa, 40MPa, 42MPa, 44MPa, 46MPa, 48MPa, 50MPa, 52MPa, 54MPa or 56MPa.

[0070] In some embodiments, the prebaked anode 2 is replaced by a cathode carbon block.

[0071] In this application, the cathode carbon block is a key electrode material used in the aluminum electrolysis process. It is made from carbon aggregates such as petroleum coke, pitch coke, electrically calcined anthracite, biochar, and graphite, and binders such as coal tar pitch, through processes including high-temperature calcination, crushing, screening, batching, kneading, molding, and baking. It possesses a stable geometric shape and good electrical conductivity and mechanical properties, enabling it to operate stably in the high-temperature, high-current, and highly corrosive aluminum electrolysis environment. The cathode carbon block typically has a regular geometric shape, such as rectangular or circular, to adapt to the structural requirements of continuous anode assemblies. The dimensions of the cathode carbon block (such as length, width, and height) should be determined according to the design requirements of the electrolytic cell and the electrolysis process conditions.

[0072] In some embodiments, the raw materials for the cathode carbon block include carbon material and a binder, wherein the carbon material accounts for 77-81% by mass and the binder accounts for 19-23% by mass. For example, the carbon material accounts for 77%, 78%, 79%, 80%, or 81% by mass, and the binder accounts for 19%, 20%, 21%, 22%, or 23% by mass.

[0073] In this application, "embedded" means that the prebaked anode 2 is completely placed or embedded in the internal space of the channel of the metal frame 1, and at least one side of the prebaked anode 2 forms a certain contact with the inner wall of the channel.

[0074] In some embodiments, the shape and size of the channels of the metal frame 1 are matched to the prebaked anode 2 for tightly accommodating the prebaked anode 2.

[0075] In some embodiments, the number of conductors 4 in the anode paste 3 of a single continuous anode assembly can be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 200, etc., depending on the volume of the continuous anode assembly, the maximum current density of the conductors 4, and the design requirements of the continuous anode assembly.

[0076] In some embodiments, the conductor 4 in the anode paste 3 is kept parallel to the conductor 4 in the prebaked anode 2.

[0077] In some embodiments, the slot can be formed along the longitudinal, transverse, or other directions of the prebaked anode 2 to meet specific current transmission or connection requirements. The extension path of the slot is not specifically limited; it can extend in a straight line or in a curved direction.

[0078] In some embodiments, the slotting includes a first slot 21 and a second slot 22, wherein the first slot 21 is in communication with the space where the anode paste 3 is located; and the second slot 22 is used to assemble the conductor 4.

[0079] Because the space between the first slot 21 and the anode paste 3 is connected, on the one hand, as the opening pores on the first slot 21 enlarge due to heating, excess binder seeps into the pores in the first slot 21 and neutralizes the surface. During the carbonization process of the binder, the carbonized body is firmly adhered to the prebaked anode 2, while preventing the problem of the anode assembly flowing out when the binder content in the anode paste 3 is high. On the other hand, when the anode paste 3 is heated to melt and generates VOCs, the first slot 21 can partially contain the generated VOC gas. The VOCs seep into the prebaked anode 2 and undergo secondary thermal decomposition on the inner wall of the pores of the prebaked anode 2, further improving the conductivity and mechanical strength of the prebaked anode 2. It also effectively avoids the problem of anode paste 3 flowing out or VOCs escaping from the periphery of the continuous anode assembly.

[0080] In some embodiments, there is at least one first slot 21 on a single prebaked anode 2, for example, there can be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, etc. The shape, size, and number of the first slots 21 are set according to actual needs to meet the requirement that the anode paste 3 and the prebaked anode 2 are integrated.

[0081] Preferably, there is one first slot 21 on a single prebaked anode 2, and the first slot is filled with anode paste 3.

[0082] In some embodiments, the first slot 21 includes a case where the original surface of the prebaked anode 2 in contact with the anode paste is milled off to increase the channels and amount of binder penetrating into the prebaked anode 2.

[0083] In some embodiments, there is at least one second slot 22 on a single prebaked anode 2, for example, there can be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, etc. The shape, size, and number of the second slots 22 can be set according to actual needs and match the conductors 4 required on the single prebaked anode 2.

[0084] Preferably, there are two second slots 22 on a single prebaked anode 2, with one end of each second slot 22 close to or in contact with the charging surface 11 of the metal frame 1, and the other end close to or in contact with the charging surface 12 of the metal frame 1.

[0085] In some embodiments, the second slot 22 is disposed perpendicular to the power input surface 11 or power output surface 12 of the metal frame 1.

[0086] In some embodiments, the second slot 22 has an open structure at one end near the metal frame 1 so that the conductor 4 in the second slot 22 can be electrically connected to the metal frame 1.

[0087] In some embodiments, the distance between the bottom end of the prebaked anode 2 extending from the bottom of the metal frame 1 and the lower opening of the channel in the metal frame 1 is not less than 20cm. Specifically, it can be 20cm, 21cm, 22cm, 23cm, 24cm, 25cm, 26cm, 27cm, 28cm, 29cm, 30cm, 31cm, 32cm, 33cm, 34cm, 35cm, 36cm, 37cm, 38cm, 39cm, or 40cm. This allows the anode paste 3 to melt, flow, form, and carbonize within the space formed by the prebaked anode 2 and the metal frame 1, preventing the fugitive emission of VOCs generated by the anode paste 3 and forming an electrical connection with the electrolytic cell system.

[0088] In this application, anode paste 3 is a paste containing carbon materials used in continuous anode components, mainly made by mixing calcined petroleum coke or pitch coke with binders such as coal tar pitch. Anode paste 3 serves as the initial material for the anode during electrolysis, and is calcined by the Joule heat generated by the conductor 4 and the heat supplied by the electrolyte to form a dense carbon body, participating in the conductive and electrochemical reactions at the bottom of the continuous anode component. The manufacturing process of anode paste 3 varies, including differences in composition, particle size, mixing temperature, and mixing time. Different processes may affect the performance of anode paste 3, but as long as it meets the requirements for the initial material of the anode in the final product, it can be considered as anode paste 3 in this patent.

[0089] In some embodiments, the adhesive paste 6 comprises a carbon material and a binder. The carbon material is selected from one or more of petroleum coke, pitch coke, calcined petroleum coke, graphite, and biomass. The binder is selected from one or more of asphalt, resin, tar, white sugar, syrup, paraffin wax, aluminum hydrogen phosphate, rosin, ammonium persulfate, starch, lignin, and machine oil.

[0090] In some embodiments, the carbon material content in the anode paste 3 is 71-79 wt%, and the binder content is 21-29 wt%. Compared to the anode paste 3 used in the prior art, the binder content in the anode paste 3 in contact with the prebaked anode in this application is increased by 1-5 wt%, improving the fluidity of the anode paste 3. Under the condition that the open pores on the groove of the prebaked anode 2 expand due to thermal expansion, the excess binder penetrates into the pores and surface of the groove. During the carbonization process of the binder, the carbonized anode paste 3 is firmly adhered to the prebaked anode 2, fusing them into one piece. Simultaneously, it repairs the damage to the prebaked anode 2 caused by the groove, fills the open pores on the groove of the prebaked anode 2, increases the bulk density, improves conductivity and mechanical strength, and avoids the negative problems that occur when the binder content in the anode paste 3 is high. An anode paste with normal asphalt content is added on top of the aforementioned anode paste with high binder content. Specifically, the mass content of the carbon material can be 71 wt%, 73 wt%, 75 wt%, 77 wt%, or 79 wt%. The mass content of the adhesive can be 21wt%, 23wt%, 25wt%, 27wt%, or 29wt%.

[0091] In some embodiments, the anode paste 3 fills the metal frame 1 and covers the top or side surface of the prebaked anode 2. This maximizes the utilization of the heat generated by the prebaked anode 2, improves the prebaking effect of the anode paste 3, avoids fugitive VOC emissions, and increases the yield of the anode paste 3.

[0092] In this application, conductor 4 is a substance or material with low resistivity that can efficiently conduct current. Such substances or materials contain a large number of free charge carriers (such as free electrons and ions), which can move directionally under the influence of an applied electric field, thereby forming a current. In this application, the material is not limited to a specific material, form, or application environment; as long as the substance or material exhibits significant conductivity under specific conditions, it is considered conductor 4 in this application.

[0093] In some embodiments, the material of the conductor 4 is selected from one or more of metals, metal alloys, and cryolite.

[0094] In some embodiments, the shape of the conductor 4 is not strictly limited and can be designed into any suitable shape as needed. It can be linear, rod-shaped, plate-shaped, sheet-shaped, or any other suitable shape. Preferably, when the conductor 4 is placed in a specific slot, its shape matches the shape of the slot, or the conductor 4 is poured into the slot in liquid form and then solidifies to ensure good electrical contact and mechanical stability.

[0095] In some embodiments, the conductor 4 is assembled within the second slot 22, which has an open structure at one end near the metal frame 1, and the conductor 4 is in contact with the metal frame 1. This ensures that the current can be stably, uniformly, and efficiently transmitted to the prebaked anode 2, thereby meeting the normal operating requirements of the electrolytic cell system. The number of conductors 4 matches the number of the second slots 22.

[0096] In some embodiments, one end of the conductor 4 is connected to a baffle 42, which is in contact with the metal frame 1. The baffle 42 facilitates the flow of current from the metal frame 1 into the conductor 4, or adds a pathway for current to flow from the metal frame 1 into the conductor 4, preventing premature flow out of the continuous anode and ensuring continuous current conduction. The shape and size of the baffle 42 match the contact surfaces of the metal frame 1 and the conductor 4 to ensure tight contact and good electrical connection. The baffle 42 can be designed as a flat, curved, or specifically shaped contact surface to accommodate different structures of the metal frame 1 and the conductor 4.

[0097] In some embodiments, the conductor 4 is fitted within the second slot 22, which has an open end near the metal frame 1. The baffle 42 is located at the opening of the second slot and contacts the metal frame 1. The conductor 4 is in contact with the baffle 42. The size of the baffle 42 matches the opening of the second slot 22 so that it can fit tightly against the opening of the second slot 22 and form a stable electrical contact with the metal frame 1. The shape of the baffle 42 can be designed according to the contact surface shape of the metal frame 1, such as a flat surface or a curved surface, to adapt to different contact requirements.

[0098] In some embodiments, the baffle 42 is made of one or more of graphite, ceramic, and graphene.

[0099] In some embodiments, one end of the conductor 4 is provided with a raised end 41, which is in contact with the metal frame 1. The main function of the raised end 41 is to act as a bridge for current transmission, efficiently guiding current from the metal frame 1 into the conductor 4. The shape and size of the raised end 41 are not limited, but its shape matches the contact surface of the metal frame 1 to ensure a tight connection, a large connection area, and good electrical contact. Simultaneously, the raised end 41 can be welded to the metal frame 1 to reduce contact resistance and improve the efficiency and stability of current transmission.

[0100] In some embodiments, the upturned head 41 extends out of the second slot 22 along the extension direction of the channel of the metal frame 1.

[0101] In some embodiments, the material of the upturned head 41 is selected from one or more of metal, metal alloy, and cryolite.

[0102] Preferably, the material of the upturned head 41 is the same as that of the conductor 4.

[0103] In some embodiments, the conductor 4 is connected to a protruding end 41 and a baffle 42 at one end near the metal frame 1. The protruding end 41 and the baffle 42 are both in contact with the metal frame 1. The baffle 42 is located between the conductor 4 and the metal frame 1, and the protruding end 41 is located on one side of the conductor 4.

[0104] In some embodiments, when there are multiple conductors 4, the conductors 4 can be freely combined with the upturned head 41 and / or the baffle 42. Taking three conductors 4 as an example, one end of two conductors 4 can be provided with an upturned head 41 or a baffle 42 respectively, and one end of one conductor 4 can be provided with both an upturned head 41 and a baffle 42.

[0105] In another embodiment of this application, refer to Figures 1-3 The bottom end of the prebaked anode 2 extends out of the metal frame 1, and the prebaked anode 2 has a first slot 21 and / or a second slot 22; the anode paste 3 fills the metal frame 1 on the top surface of the prebaked anode 2 and covers the top surface of the prebaked anode 2 and the first slot 21; the conductor 4 is disposed in the second slot 22 and in the anode paste 3.

[0106] Specifically, the upper part of the prebaked anode 2 is fitted inside the channel of the metal frame 1, and the bottom of the prebaked anode 2 extends out of the lower opening of the channel of the metal frame 1. A first slot 21 and / or a second slot 22 are formed on the top surface of the prebaked anode 2. A conductor 4 is arranged in the second slot 22. One end of the conductor 4 is connected to the inner surface of the metal frame 1. The anode paste 3 is filled inside the metal frame 1 and located on the top surface of the prebaked anode 2 and in the first slot 21. The conductor 4 is inserted through the accumulated anode paste 3 and connected to the metal frame 1.

[0107] In use, the continuous anode assembly is installed on the aluminum electrolytic cell. After current is applied, the current flows through the metal frame 1 and conductor 4 into the prebaked anode 2, heating up the temperature of the prebaked anode 2. The high-temperature prebaked anode 2 is heated, melted, shaped, and prebaked into anode paste 3. The molten anode paste 3 automatically flows downward to the anode carbon block, and the binder penetrates into the prebaked anode carbon block. When the electrolytic cell transitions from the baking and start-up stages to the normal operation stage, the prebaked anode 2 is gradually consumed, and the anode paste 3 on it transitions from prebaking to formal baking, gradually transforming into a carbonized body with a resistivity of less than 70 μΩ·m, a mechanical strength of greater than 30 MPa, and integrated with the top surface of the prebaked anode 2 and the first slot 21. After the prebaked anode is completely consumed, the carbonized body transformed from the anode paste replaces the prebaked anode, and the bottom surface of the carbonized body serves as the bottom surface of the continuous anode assembly. Meanwhile, a new metal frame 1 and conductor 4 are connected to the upper opening of the channel of the metal frame 1. New anode paste 3 is added to the space between the metal frame 1 and conductor 4. The new anode paste 3 is heated, melted, shaped and baked and gradually transformed into carbonized body, becoming part of the continuous anode assembly. As the continuous anode is consumed, the above process is repeated.

[0108] In some embodiments, the prebaked anode 2 is composed of at least one prebaked block 23, and the at least one prebaked block 23 has grooves formed on its unidirectional surface. Multiple prebaked blocks 23 of the same specifications are bonded together to form a single prebaked anode 2. Specifically, the prebaked blocks 23 constituting the prebaked anode 2 can be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, etc. Preferably, the prebaked blocks 23 constituting the prebaked anode 2 are 2 or 3.

[0109] In some embodiments, the connection method of the prebaked blocks 23 is not limited, and the prebaked blocks 23 are connected to each other in at least one of the following ways: In the side-connection configuration, the prebaked blocks 23 have mutually matching side structures, allowing adjacent prebaked blocks 23 to be tightly and securely connected together along their sides. This side-connection design allows the prebaked blocks 23 to expand horizontally, thereby forming a prebaked anode 2 with the desired width and length.

[0110] In a stacking configuration, the prebaked blocks 23 have flat or tenon-and-mortise structured top and bottom surfaces, allowing one prebaked block 23 to be stably stacked on top of another. This stacking design allows the prebaked blocks 23 to be stacked vertically to form a prebaked anode 2 with the desired height.

[0111] The size and shape of the prebaked anode 2 can be flexibly adjusted by side connection and / or stacking to meet the needs of different electrolytic cells.

[0112] In some embodiments, a side connection is preferred.

[0113] When there are two prebaked blocks 23 constituting the prebaked anode 2, each prebaked block 23 has a first slot 21 on its top surface to connect the space where the anode paste 3 is located, and at least one prebaked block 23 has a second slot 22 inside for placing the conductor 4. The first slots 21 on the two prebaked blocks 23 can be in a straight line, parallel, or staggered. Preferably, the slots on the two prebaked blocks 23 are parallel to maximize the current supply for heating the prebaked anode 2.

[0114] When there are three prebaked blocks 23 constituting the prebaked anode 2, the three prebaked blocks 23 are bonded together by side to form the prebaked anode 2. The top surfaces of the three prebaked blocks 23 are all provided with parallel first slots 21, and the interiors of the three prebaked blocks 23 are all provided with second slots 22.

[0115] In some embodiments, there may be multiple first slots 21 and second slots 22 on each prebaked block 23. The first slots 21 are evenly distributed on the top surface of the prebaked block 23 to enhance the connection strength between the carbonized anode paste 3 and the prebaked block 23. In order to heat evenly, when multiple prebaked blocks 23 constitute the prebaked anode 2, the number of second slots 22 on each prebaked block 23 is the average of the total number of second slots 22 on the prebaked anode 2, and they are evenly distributed in each prebaked block 23.

[0116] In some embodiments, the plurality of prebaked blocks 23 are connected by an adhesive paste 6. The adhesive paste 6 comprises a carbon material and a binder.

[0117] In some embodiments, the carbon material is selected from one or more of petroleum coke, pitch coke, calcined petroleum coke, graphite, and biomass.

[0118] In some embodiments, the binder is selected from one or more of asphalt, resin, tar, white sugar, syrup, paraffin, dialuminum hydrogen phosphate, rosin, ammonium persulfate, starch, and engine oil.

[0119] In another embodiment of this application, refer to Figure 4 The continuous anode assembly includes at least two prebaked anodes 2, each prebaked anode 2 is in contact with the inner wall of the channel and forms an anode cavity between the prebaked anodes 2, the anode paste 3 is filled in the anode cavity, and the conductor 4 is disposed in the slot.

[0120] Specifically, one end of each of the prebaked anodes 2 is in contact with the charging surface 11 and the charging surface 12 of the metal frame 1, respectively. The other ends of the prebaked anodes 2 form an anode cavity, which is coaxially arranged with the channel of the metal frame 1. The anode paste 3 is filled in the anode cavity. Each prebaked anode 2 has a first slot 21 and a second slot 22 on its top. The first slot 21 is located on the side of the prebaked anode 2 away from the metal frame 1 and communicates with the space where the anode paste 3 is located.

[0121] In use, the continuous anode assembly is installed on the aluminum electrolytic cell. After current is applied, the current on the anode rod 5 flows through the metal frame 1 and conductor 4 into the prebaked anode 2, heating it and raising its temperature. The prebaked anodes 2 bond firmly together. At the same time, the high-temperature prebaked anodes 2 are heated, melted, shaped, and calcined into anode paste 3. The anode paste 3 is firmly connected to the prebaked anodes 2 and gradually calcined into a carbonized body with a resistivity of less than 70 μΩ·m and a mechanical strength of greater than 30 MPa, becoming part of the continuous anode. When the electrolytic cell transitions to normal operation after the calcination and start-up stages... During this stage, the prebaked anode 2 and the carbonized body are gradually consumed. Simultaneously, a new metal frame 1 is connected to the upper opening of the metal frame 1. Adhesive paste 6 is coated on the top surface of the prebaked anode 2, and a new prebaked anode 2 is placed on the adhesive paste 6. A conductor 4 connected to the metal frame 1 is placed within the groove of the prebaked anode 2. New anode paste 3 is added to the anode cavity formed by the new prebaked anode 2. The new anode paste 3, after heating, melting, shaping, and baking, gradually transforms into a carbonized body that is firmly bonded to the prebaked anode 2. The prebaked anodes 2 are firmly bonded together. This process is repeated as the carbonized body and prebaked anode 2 are consumed. When the anode guide rod 5 applies a certain clamping force to the inlet surface 11 and outlet surface 12 of the metal frame 1 to lift the continuous anode, the prebaked anodes 2 on both sides and the anode paste 3 or carbonized body in the middle together bear the clamping force without shrinking or deforming, and without causing the anode to fall out of the fixture. At the same time, the prebaked anode 2 and the carbonized body are bonded together, and there is no displacement or cracking between them.

[0122] In some embodiments, the plurality of prebaked anodes 2 can be 1, 2, 3, 4, 5, 6, etc. Preferably, there can be 2 prebaked anodes 2.

[0123] When there are two prebaked anodes 2, one prebaked anode 2 is in contact with the charging surface 11 of the metal frame 1, and the other prebaked anode 2 is in contact with the charging surface 12 of the metal frame 1. An anode cavity extending along the channel of the metal frame 1 is formed between the two prebaked anodes 2. The anode paste 3 is filled into the anode cavity to form a continuous anode assembly.

[0124] In some embodiments, there can be multiple first slots 21 and second slots 22 on each of the prebaked anodes 2, such as 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, etc.

[0125] In some embodiments, the extension paths of the first slot 21 and the second slot 22 are not specifically limited; they can extend in a straight line or in a curved direction.

[0126] In some embodiments, the second slots 22 on the plurality of prebaked anodes 2 may be arranged parallel to each other, grouped on the same straight line, or staggered. Preferably, the second slots 22 on the plurality of prebaked anodes 2 are parallel to each other, and the second slots 22 of the prebaked anodes 2 that are grouped together are on the same straight line.

[0127] In some embodiments, the prebaked anode 2 is composed of at least one prebaked block 23, and multiple prebaked blocks 23 are combined together by a specific connection method to form an integral anode with the desired shape and size. Multiple prebaked blocks 23 of the same specifications are bonded together to form an integral prebaked anode 2. Specifically, the prebaked blocks 23 constituting the prebaked anode 2 can be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, etc. Preferably, the prebaked blocks 23 constituting the prebaked anode 2 are 2 or 3.

[0128] In some embodiments, the connection method of the prebaked blocks 23 is not limited, and the prebaked blocks 23 are connected to each other in at least one of the following ways: In the side-connection configuration, the prebaked blocks 23 have mutually matching side structures, allowing adjacent prebaked blocks 23 to be tightly and securely connected together along their sides. This side-connection design allows the prebaked blocks 23 to expand horizontally, thereby forming a prebaked anode 2 with the desired width and length.

[0129] The prebaked blocks 23 are stacked vertically, with flat top and bottom surfaces, allowing one prebaked block 23 to be stably stacked on top of another. This vertical stacking design allows the prebaked blocks 23 to be stacked vertically to form a prebaked anode 2 with the desired height.

[0130] Through side connection and / orThe stacking method allows for flexible adjustment of the size and shape of the prebaked anode 2 to meet the needs of different electrolytic cells.

[0131] In some embodiments, a stacking method is preferred.

[0132] When there are three prebaked blocks 23 constituting the prebaked anode 2, each prebaked block 23 has a second slot 22 on its top surface for placing the conductor 4. The second slots 22 on the three prebaked blocks 23 can be in the same straight line or plane, or they can be arranged in parallel or staggered. Preferably, the second slots 22 on the three prebaked blocks 23 are arranged in parallel to provide the maximum current for heating the prebaked anode 2. Each prebaked block 23 has a first slot 21 on its side. The first slots 21 on the three prebaked blocks 23 can be in the same straight line or plane, or they can be arranged in parallel or staggered.

[0133] In some embodiments, each of the prebaked blocks 23 may have multiple first slots 21 and second slots 22. Multiple first slots 21 are evenly distributed on the side of the prebaked blocks 23 to enhance the connection strength between the anode paste 3 carbonized body and the prebaked blocks 23. Multiple second slots 22 are evenly distributed on the top of the prebaked blocks 23.

[0134] In some embodiments, the plurality of prebaked blocks 23 are connected by an adhesive paste 6. The adhesive paste 6 comprises a carbon material and a binder.

[0135] In some embodiments, the carbon material is selected from one or more of petroleum coke, pitch coke, calcined petroleum coke, graphite, and biomass.

[0136] In some embodiments, the binder is selected from one or more of asphalt, resin, tar, white sugar, syrup, paraffin, dialuminum hydrogen phosphate, rosin, ammonium persulfate, starch, and engine oil.

[0137] In another embodiment of this application, a method for preparing a continuous anode assembly is provided, comprising: pre-fabricating a prebaked anode 2 having at least one slot; placing a conductor 4 in at least one of the slots; fitting the slotted area of ​​the prebaked anode 2 into a metal frame 1, such that the conductor 4 is connected to the metal frame 1, and a portion of the prebaked anode 2 extends out of the metal frame 1; filling at least one surface of the prebaked anode 2 within the metal frame 1 with anode paste 3, or laying the conductor 4 within the metal frame 1 and filling at least one surface of the prebaked anode 2 with anode paste 3; the space where the anode paste 3 is located is in communication with at least one of the slots.

[0138] In this application, the prebaked anode 2 is prefabricated using conventional methods. For example, carbon materials and binders are mixed in a kneading pot according to a predetermined formula to form a non-flowing loose paste. The paste is then loaded into a mold of a special molding machine (e.g., a vibratory molding machine). The anode green is formed by the force of the molding machine. The green is then placed in a special ring-shaped roasting furnace. In an air-isolated environment, the binder in the green is carbonized by the heat released after the fuel combustion. The coke formed after carbonization binds the carbon materials together to form a highly conductive and high-strength prebaked anode 2.

[0139] In some embodiments, the roasting temperature of the annular roasting furnace is higher than 1150°C, the binder coking rate is as high as 70%, and the carbonization rate is over 99%.

[0140] In some embodiments, the prebaked anode 2 has a bulk density of 1.56~1.81 g / cm³. 3 Its resistivity is 36~56 μΩ·m, and its compressive strength is 32~56 MPa. For example, its bulk density is 1.56 g / cm³. 3 1.61 g / cm 3 1.66 g / cm 3 1.71g / cm 3 1.76 g / cm 3 Or 1.81 g / cm 3 The resistivity is 36 μΩ·m, 38 μΩ·m, 40 μΩ·m, 42 μΩ·m, 44 μΩ·m, 46 μΩ·m, 48 μΩ·m, 50 μΩ·m, 52 μΩ·m, 54 μΩ·m or 56 μΩ·m, and the compressive strength is 32MPa, 34MPa, 36MPa, 38MPa, 40MPa, 42MPa, 44MPa, 46MPa, 48MPa, 50MPa, 52MPa, 54MPa or 56MPa.

[0141] In some embodiments, the slot may be formed along the axial, radial, or other directions of the prebaked anode 2 to meet specific current transmission or connection requirements. The extension path of the slot is not specifically limited; it may extend in a straight line or in a curved direction.

[0142] In some embodiments, the number of slots is at least one; for example, it can be one, two, three, four, five, six, seven, eight, nine, ten, etc. The number of slots can be set according to actual needs.

[0143] In some embodiments, the adhesive paste 6 comprises a carbon material and a binder. The carbon material is selected from one or more of petroleum coke, pitch coke, calcined petroleum coke, graphite, and biomass. The binder is selected from one or more of asphalt, resin, tar, white sugar, syrup, paraffin wax, dialuminum hydrogen phosphate, rosin, ammonium persulfate, starch, and machine oil.

[0144] In some embodiments, the carbon material in the anode paste 3 has a mass content of 71-79 wt%, and the binder has a mass content of 21-29 wt%. Specifically, the mass content of the carbon material can be 71 wt%, 73 wt%, 75 wt%, 77 wt%, or 79 wt%. The mass content of the binder can be 21 wt%, 23 wt%, 25 wt%, 27 wt%, or 29 wt%.

[0145] In some embodiments, at least two prebaked blocks 23 are connected to form the prebaked anode 2. Specifically, the prebaked anode 2 is formed by bonding at least two prebaked blocks 23 together. A selected adhesive material is uniformly applied to the bonding surface of the prebaked blocks 23. Subsequently, the prebaked blocks 23 coated with adhesive material are joined together, ensuring that the bonding surfaces are tightly adhered. The prebaked blocks 23 are fixed using clamps or other fixing devices to prevent displacement or misalignment during the bonding process. Depending on the properties of the adhesive material, appropriate curing conditions (such as temperature, time, etc.) are selected for curing treatment to allow the adhesive material to fully cure and form a strong adhesive layer.

[0146] In some embodiments, the adhesive material is bonded using an adhesive paste, which includes a carbon material and an adhesive.

[0147] In some embodiments, the carbon material is selected from one or more of petroleum coke, pitch coke, calcined petroleum coke, graphite, and biomass.

[0148] In some embodiments, the binder is selected from one or more of bitumen, resin, tar, and lignin.

[0149] In some embodiments, a raised end 41 and / or a baffle 42 is provided at one end of the conductor 4. The connection between the raised end 41 and / or the baffle 42 and the conductor 4 can be varied, including but not limited to: Integrated molding: The upturned head 41 and / or baffle 42 are integrally molded with the main body of conductor 4 through processes such as casting, forging, and extrusion to form an integral structure.

[0150] Welding: The upturned head 41 and / or the baffle 42 are fixed to the conductor 4 by welding. Welding can be performed by various methods such as arc welding, laser welding, and brazing. The specific method is determined according to the material properties and connection requirements.

[0151] Mechanical connection: The upturned head 41 and / or baffle 42 are fixed to the conductor 4 by mechanical fasteners such as bolts, screws, and clips.

[0152] Adhesion: Use adhesive to bond the baffle 42 to the conductor 4.

[0153] In some embodiments, the conductor 4 is made of one or more of metals, metal alloys, cryolite, or alumina.

[0154] In some embodiments, the material of the upturned head 41 is selected from one or more of metal, metal alloy, cryolite or alumina.

[0155] In some embodiments, the baffle 42 is made of one or more of graphite, ceramic, and graphene.

[0156] In another embodiment of this application, an aluminum electrolytic cell is provided, comprising: an electrolytic cell body; a cathode disposed at the bottom of the electrolytic cell body; and a continuous anode assembly installed on the electrolytic cell body, wherein the continuous anode assembly and the cathode form an electrical connection path through an electrolyte and liquid aluminum.

[0157] In some embodiments, the continuous anode assembly includes a metal frame 1, a prebaked anode 2, an anode paste 3, and a conductor 4. The metal frame 1 has a channel with openings at both ends. The prebaked anode 2 is fitted inside the channel of the metal frame 1 and extends out of the metal frame 1. The prebaked anode 2 located in the channel has at least one slot. The anode paste 3 fills the metal frame 1 and contacts at least one surface of the prebaked anode 2. The space where the anode paste 3 is located communicates with at least one of the slots. The conductor 4 is assembled in at least one of the slots and / or in the anode paste 3. The conductor 4 is connected to the metal frame 1.

[0158] In some embodiments, the bottom surface of the continuous anode assembly has an irregular shape, which includes: the bottom surface of the continuous anode assembly is provided with a plurality of protrusions and / or recesses, including but not limited to a plurality of V-shaped, arched, roof-shaped or semi-cylindrical protrusions and / or recesses, thereby increasing the surface area of ​​the bottom surface and increasing the contact area, tightness and uniformity with the underlying resistive layer.

[0159] The resistive layer is mainly composed of any one or more of carbon materials, graphite, biochar, and metallic aluminum. It is located between the continuous anode assembly and the cathode and is in contact with both the continuous anode assembly and the cathode, conducting the current on the continuous anode assembly to the cathode.

[0160] Because the bottom surface area of ​​a single continuous anode assembly is more than 8 times that of an existing anode, the contact area and tightness between the resistive layer laid on the upper surface of the cathode and different parts of the continuous anode assembly are inconsistent, resulting in uneven current distribution on the continuous anode assembly, and even burning out the continuous anode assembly.

[0161] By setting several protrusions and / or depressions on the bottom surface of the continuous anode assembly, the protrusions are inserted into the resistive layer. At the same time, under the pressure of the continuous anode assembly's own weight, the resistive layer corresponding to the depressions protrudes and contacts the depressions of the continuous anode assembly. This achieves uniform and tight contact between the bottom surface of the continuous anode assembly and the resistive layer, solving the problem of uneven current distribution in the continuous anode assembly and reducing the impact voltage during the roasting of the electrolytic cell.

[0162] When the upper surface of the cathode is irregularly shaped, the protrusions and / or depressions on the bottom surface of the continuous anode assembly correspond and match it, increasing the effective area between the continuous anode assembly and the cathode. Under the premise that the current through the electrolytic cell is constant, the current density is reduced, thus reducing energy consumption. Alternatively, under the premise that the current density of the electrolytic cell is kept constant, the current intensity of the electrolytic cell is increased, thus increasing the production capacity. For example, if the upper surface of the cathode and the bottom surface of the continuous anode assembly are irregularly shaped, the surface area of ​​the relatively flat area increases by 1.5 times, then the current intensity of the electrolytic cell can be increased by 1.5 times, and the unit production capacity will increase by 1.5 times.

[0163] The technical solution of this application will be further described in detail below with reference to specific exemplary embodiments.

[0164] Coking rate The coking value of the binder in anode paste 3 is related to the calcination rate, the maximum calcination temperature, and the calcination environment; all three factors work together. A slower calcination rate results in a higher coking value under the same conditions; a higher calcination temperature also results in a higher coking value under the same conditions; and under air-isolated conditions, the coking value of the binder is higher under the same conditions. The coking value of the binder is expressed as the coking rate; a higher coking value indicates a higher coking rate, and vice versa.

[0165] The green body of the prebaked anode 2 is roasted at a high temperature above 1150℃ under air-isolated conditions. Its coking rate is mainly related to the roasting speed and the device of the annular roasting furnace. The slower the roasting speed, the higher the coking rate of the binder under the same conditions. The better the sealing effect of the annular roasting furnace device, the higher the coking rate of the binder under the same conditions, and vice versa.

[0166] The coking rate is generally measured using precision laboratory instruments and devices. The measurement method for anode paste 3 is as follows: First, weigh anode paste 3 with a mass of W1. Then, carbonize the anode paste 3 in a simulated actual working environment. Finally, weigh the carbonized anode paste 3 with a mass of W2. The binder content in anode paste 3 is A wt%. Then the coking rate of the anode paste 3 = .

[0167] The method for measuring the coking rate of prebaked anode 2 is as follows: First, a green sample with a mass of W1 is taken from the green billet to simulate the actual prebaked anode 2 baking process, or it is placed in a ring-type baking furnace and baked together with a batch of green billets. Then, the mass W2 of the baked sample is weighed. The binder content in the green billet is A wt%. Then the coking rate of prebaked anode 2 = .

[0168] Carbonization rate The carbonization rate of anode paste 3 reflects the degree of coking reaction of the binder in anode paste 3. The higher the degree of coking reaction, the lower its resistivity, and vice versa. Anode paste 3 that has not undergone a coking reaction has the highest resistivity. The degree of coking reaction is expressed by the carbonization rate, which, under the same conditions, is mainly related to the roasting temperature. That is, the higher the roasting temperature, the higher the carbonization rate of anode paste 3, and vice versa. Because the temperature is inconsistent in different parts of the continuous anode, the temperature is high near the lower part and the central region of the anode, resulting in a high carbonization rate of anode paste 3 in these areas; the temperature is low near the upper part and the surrounding areas of the anode, resulting in a low carbonization rate of anode paste 3 in these areas, or the carbonization reaction has not yet begun, and the carbonization rate is zero.

[0169] The carbonization rate of prebaked anode 2 reflects the degree of coking reaction of the binder in the green body, expressed as carbonization rate. It is mainly related to the maximum roasting temperature and time of the annular roasting furnace. That is, the higher the maximum roasting temperature of the annular roasting furnace and the longer the roasting time exceeds the minimum limit, the higher the carbonization rate. Because the binder content in the green body is low, the roasting temperature is generally higher than 1150℃ and the roasting time exceeds 192 hours. Therefore, the carbonization rate of prebaked anode 2 is basically constant, close to 100%, meaning that the binder in the green body is basically completely carbonized.

[0170] The carbonization rate of anode paste 3 is generally measured using precision laboratory instruments and devices. The measurement method for anode paste 3 is as follows: First, weigh anode paste 3 with a binder content of A wt% and a mass of W1 to prepare a sample. Then, calcine the sample at a simulated actual working temperature and cool it to room temperature. Next, use a resistivity meter to measure the resistivity R1 of the calcined sample. Then, under the same conditions, heat the sample to 1150℃ and hold it for 3 hours, then cool it to room temperature. Use the same resistivity meter to measure the resistivity R2 of the sample at high temperature.

[0171] Then the carbonization rate of the anode paste 3 = .

[0172] Because the binder content in the green body is low, the baking temperature is generally higher than 1150℃ and the baking time exceeds 192 hours, so the carbonization rate of the prebaked anode 2 is calculated as 100%.

[0173] Example 1 Reference Figures 1-3A continuous anode assembly includes a metal frame 1, a prebaked anode 2, anode paste 3, and a conductor 4. The metal frame 1 has an input surface 11 and an output surface 12 on both sides, with openings at the top and bottom. Three anode guide rods 5 are connected to each input surface 11 and output surface 12 on both sides of the metal frame 1. The prebaked anode 2 is composed of three prebaked blocks 23, whose sides are bonded together with adhesive paste 6 to form the prebaked anode 2. The prebaked anode 2 is fitted inside the metal frame 1, with its bottom end extending 20 cm from the lower opening of the metal frame 1. Each of the three prebaked blocks 23 has a first slot 21 and two second slots 22 at its top. A conductor 4 is placed in each second slot 22. The metal frame 1 at the top of the prebaked anode 2 is first filled with anode paste 3 with a binder content 2.5% higher than normal, and the first slot 21 is filled. Then, anode paste 3 with a binder content of normal value is added to the upper surface of the anode paste 3, and several conductors 4 are placed in the anode paste 3. At least one end of the conductor 4 is connected to a protruding head 41 and / or a baffle 42. The protruding head 41 is connected to the upper surface of the conductor 4 and is in contact with the incoming surface 11 and / or the outgoing surface 12 of the metal frame 1.

[0174] The prebaked anode 2 has a bulk density of 1.62 g / cm³. 3 It has a resistivity of 53 μΩ·m, a compressive strength of 42MPa, and a coking rate of 75%.

[0175] Anode paste 3 is composed of petroleum coke and pitch, with a petroleum coke content of 76 wt% and a pitch content of 24 wt%.

[0176] Three sets of continuous anode assemblies were installed above the cathode of a 180Ka aluminum electrolytic cell. The distance between the bottom of the continuous anode and the cathode was 15-30cm. The continuous anode and the top of the cathode were sealed with insulation cotton. High-temperature inert gas was introduced into the space between the bottom of the continuous anode and the cathode to bake the cathode and continuous anode. The temperature of the cathode and the lower part of the continuous anode was gradually raised from room temperature to 890-920℃. High-temperature liquid electrolyte (composed of cryolite, including a small amount of alumina) was rapidly poured into the electrolytic cell and buried 10-30cm below the continuous anode. A series of currents were immediately introduced into the aluminum electrolytic cell. The entire series of currents was increased within 10 minutes. The impact voltage was less than 3.26V. The anode current was evenly distributed. Other operating aluminum electrolytic cells in the series did not experience anode effects due to the rapid increase in the entire series of currents. The aluminum electrolytic cell was put into normal operation 30 days after startup. As the prebaked anode 2 was consumed, a new aluminum frame, conductor, and anode paste were added to the upper opening of the metal frame 1.

[0177] During the high-temperature inert gas calcination of the aluminum electrolytic cell, the temperature of the cathode and prebaked anode 2 is first raised. Then, the high-temperature prebaked anode 2 is heated, melted, cast, and prebaked to prebake the anode paste 3 in contact with its top surface. At this time, no additional energy is required to calcine the anode paste 3, thus saving energy. When the anode paste 3 is heated to the point of melting and VOCs are generated, there are no problems with paste flow or VOCs escaping around the continuous anode. The VOC value at the top of the aluminum frame is measured with a portable VOC detector and is between 8 and 12 mg / NM. 3 Between them. Because anode paste 3 is located on the top surface of prebaked anode 2, the time for initial heating, melting, casting, and prebaking of the anode paste is extended by approximately 48 hours, reducing the rate of heating, melting, casting, and prebaking of the anode paste. The heating rate of anode paste 3 is controlled at 3℃ / hour, promoting the penetration of anode paste 3 into the prebaked anode, reducing the generation of VOCs and the carbonization rate of the binder. The coking rate of the binder is above 86%, enhancing the connection between anode paste 3 and prebaked anode 2. After being heated, melted, cast, and baked using the heat of prebaked anode 2, anode paste 3 is tightly bonded to prebaked anode 2, forming a strong, non-separating, high-strength integral structure.

[0178] Anode paste 3 is located on the top surface of prebaked anode 2. The time for initial heating, melting, casting, and prebaking of anode paste 3 is extended by approximately 72 hours, while the rate of heating, melting, casting, and prebaking of anode paste 3 is reduced. The heating rate of anode paste 3 is controlled at 1℃ / hour, promoting its penetration into the prebaked anode 2 and reducing VOC generation and binder carbonization rates. Through laboratory simulation and testing under the same conditions, the coking rate of the binder in anode paste 3 was measured to be approximately 86%, enhancing the bond between anode paste 3 and prebaked anode 2. Anode paste 3, heated, melted, cast, and baked using the resistance heat of prebaked anode 2, forms a strong, non-separating, and high-strength integral bond with prebaked anode 2.

[0179] As the prebaked anode 2 is consumed, a series of currents gradually enter the anode paste 3 through the aluminum frame and conductor 4, further roasting the anode paste 3. Through laboratory simulation and testing of the coking reaction degree of the anode paste 3 under the same conditions, the carbonization rate of the anode paste 3 was measured to be over 98%.

[0180] In order to clamp and lift the continuous anode, the anode guide rod 5 applies a certain clamping force to the inlet surface 11 and outlet surface 12 of the aluminum frame. When the clamping force moves from the end face of the prebaked anode 2 inside the aluminum frame to the end face of the carbonized body, the operation of the continuous anode is observed on site every day. It is found that the carbonized body of the anode paste 3 lifts the prebaked anode 2 and the prebaked anode 2 does not fall off from under the carbonized body.

[0181] Example 2 Reference Figure 4A continuous anode assembly includes a metal frame 1, two sets of prebaked anodes 2, anode paste 3, and conductors 4. The metal frame 1 has an input surface 11 and an output surface 12 on its two sides, with openings at the top and bottom. Three anode guide rods 5 are connected to each input surface 11 and output surface 12 on both sides of the metal frame 1. Each set of prebaked anodes 2 is composed of two prebaked blocks 23 stacked vertically. Each prebaked block 23 has a first slot 21 on its side and two second slots 22 on its top. The two sets of prebaked anodes 2 are respectively fitted inside the metal frame 1. The bottom end of each set of prebaked anodes 2 extends beyond the lower opening of the metal frame 1, with the extended portion 35 cm away from the lower opening. One set of prebaked anodes 2 contacts the input surface 11 of the metal frame 1, and the other set contacts the output surface 12. The second slots 22 on the top of the prebaked block 23 point towards either the input surface 11 or the output surface 12 of the metal frame 1. Two sets of prebaked anodes 2 form an anode cavity, which is filled with anode paste 3. The first slot 21 is connected to the anode cavity. A conductor 4 is placed in each second slot 22. One end of each conductor 4 is connected to a baffle 42 and / or a protruding end 41. The protruding end 41 is connected to the upper surface of the conductor 4. The baffle 42 is in contact with the power input surface 11 or the power output surface 12 of the metal frame 1. The protruding end 41 is located at the end of the second slot 22 near the metal frame 1 and is in contact with the power input surface 11 or the power output surface 12 of the metal frame 1. The baffle 42 blocks the opening of the slot near the metal frame 1.

[0182] The prebaked anode 2 has a bulk density of 1.62 g / cm³. 3 It has a resistivity of 53 μΩ·m, a compressive strength of 42MPa, and a coking rate of 75%.

[0183] Anode paste 3 is composed of petroleum coke and pitch, with a petroleum coke content of 76 wt% and a pitch content of 24 wt%.

[0184] In a 180 kcal / kg aluminum electrolytic cell, a layer of calcined petroleum coke particles with a diameter ranging from 2 to 4 mm is uniformly laid on the cathode surface. Subsequently, three sets of continuous anode assemblies are installed on top of this layer of calcined petroleum coke particles. Next, a series of currents are simultaneously applied to these three sets of continuous anode assemblies. The current first passes through the aluminum frame and conductor 4, then enters the prebaked anode 2. The current flows inside the prebaked anode 2, then through the layer of calcined petroleum coke particles, then through the cathode, and finally conducts to the next adjacent aluminum electrolytic cell. After a 96-hour roasting process, the temperature of the electrolytic cell gradually rises to approximately 700°C. At this point, the continuous anode assemblies are gradually raised. During this process, the anode paste 3 in contact with the prebaked anode 2 begins to carbonize, and the anode paste 3 and the prebaked anode 2 begin to adhere tightly together. When the temperature of the aluminum electrolytic cell further rises to 920°C or higher, liquid electrolyte is poured into the electrolytic cell, and the continuous anode assemblies continue to be raised, thus officially starting the aluminum electrolytic cell. The aluminum electrolytic cell gradually transitions to normal operation within 30 days after startup. As the prebaked anode 2 and anode paste are continuously consumed, new aluminum frames, conductors, prebaked anodes, and anode paste 3 are added in a timely manner at the top of the aluminum frame to ensure the continuous and stable operation of the electrolytic cell, a user-friendly operating environment, and a high degree of automation.

[0185] During the roasting process, the initial value of the series current was set at 10 kcal. After 25 minutes of energization, the series current gradually increased to 181 kcal. During this process, the cell control box displayed an impulse voltage of 2.82 V, and the current distribution on the anode was uniform. Notably, other operating aluminum electrolysis cells in the series did not exhibit an anode effect despite the series current not reaching full current in a short time. The main reason is that with the continuous anode assembly, the prebaked anode 2 has a low resistivity, eliminating the need for rapid carbonization of the anode paste 3 and the need for the anode cone in conventional technology to conduct current, thus eliminating safety and pollution hazards. During the roasting stage of the aluminum electrolysis cell, the resistance heat generated when the series current passes through the prebaked anode 2 begins to play a role, gradually heating and raising the temperature of the prebaked anode 2. Subsequently, the prebaked anode 2 begins to exert its heating effect, causing the anode paste 3 in contact with it to undergo heating, melting, casting, and prebaking. During this period, roasting the anode paste 3 does not require additional energy input, thus achieving energy-saving effects.

[0186] A portable VOC detector was used for testing, and the results showed that the VOC values ​​were between 3 and 6 mg / NM. 3The main reason is that the binder in the anode paste 3 and the VOCs generated by the binder penetrate into the interior of the prebaked anode 2 and undergo a secondary thermal decomposition reaction on the inner wall of the pores of the prebaked anode 2, repairing the prebaked anode 2 damaged by the slotting. When the anode paste 3 is heated to a molten state and generates volatile organic compounds (VOCs), there is no problem of paste flow or VOC escape around the continuous anode. At the same time, this process not only helps to further improve the conductivity of the prebaked anode 2, but also enhances its mechanical strength.

[0187] When the series current is conducted into the continuous anode and then into the prebaked anode 2, the resistance heat generated by the series current through the prebaked anode 2 begins to further heat and raise the temperature of the prebaked anode 2. The prebaked anode 2 is then further heated, melted, cast, and prebaked to the anode paste 3 in contact with its surface. At this time, no additional energy is required to bake the anode paste, so energy is saved and the carbonization rate of the anode paste 3 reaches more than 98%.

[0188] The continuous anode current distribution is uniform, and the carbonized anode paste 3, under the protection of the prebaked anode 2, the metal frame 1, and the anode paste 3, does not exhibit oxidation or cracking. When the anode guide rod 5 applies a certain clamping force to the aluminum frame's input surface 11 and output surface 12, the anode paste 3 or the carbonized body, together with the prebaked anode 2, withstands the clamping force without shrinking or deforming, thus preventing any technical accidents caused by the continuous anode detaching. At the same time, the prebaked anode 2 and the carbonized body are firmly bonded, and the carbonized body and the anode paste do not detach from the anode cavity formed by the prebaked anode 2.

[0189] Example 3 Reference Figure 5 A continuous anode assembly includes a metal frame 1, two sets of prebaked anodes 2, anode paste 3, and a conductor 4. Each set of prebaked anodes 2 has several protrusions 24 on its bottom surface. These protrusions 24 are inverted isosceles triangles, which increase the surface area of ​​the bottom surface, making it approximately 1.5 times the surface area of ​​a flat bottom surface. The remaining structure and composition of this continuous anode assembly are consistent with those of the continuous anode assembly in Example 2.

[0190] In a 180 kcal / kg aluminum electrolytic cell, a layer of calcined petroleum coke particles 7 with a particle size ranging from 2 to 4 mm is uniformly laid on the cathode surface as a resistive layer. Subsequently, three sets of continuous anode assemblies are installed on top of this layer of calcined petroleum coke particles 7, with the protrusion 24 on the bottom surface of each prebaked anode inserted into the calcined petroleum coke particles 7. Simultaneously, under the pressure of the continuous anode's own weight, the calcined petroleum coke particles 7 corresponding to the depression 25 on the bottom surface of the prebaked anode protrude and contact the depression 25, achieving uniform and tight contact between the entire bottom surface of the prebaked anode and the resistive layer. Next, a series of currents are simultaneously applied to these three sets of continuous anode assemblies. The current first passes through the aluminum frame and conductor 4, and then enters the prebaked anode 2. The current flows inside the prebaked anode 2, then passes through the layer of calcined petroleum coke particles, then through the cathode, and finally conducts to the next adjacent aluminum electrolytic cell. After a 96-hour roasting process, the temperature of the electrolytic cell gradually and uniformly rises to above 760°C. At this point, the continuous anode assemblies are gradually raised. During this process, the anode paste 3, which is in contact with the prebaked anode 2, begins to carbonize, and the anode paste 3 and the prebaked anode 2 begin to adhere tightly together. When the temperature of the aluminum electrolysis cell further increases to 920°C or higher, liquid electrolyte is poured into the electrolysis cell, and the continuous anode assembly is continuously raised, thus officially starting the aluminum electrolysis cell. The aluminum electrolysis cell gradually transitions to normal operation within 30 days after startup. As the prebaked anode 2 and anode paste are continuously consumed, new aluminum frames, conductors, prebaked anodes, and anode paste 3 are added in a timely manner at the upper position of the aluminum frame to ensure the continuous and stable operation of the electrolysis cell, a user-friendly operating environment, and a high degree of automation.

[0191] During calcination, the initial value of the series current was set at 10 kcal. After 25 minutes of energization, the series current gradually increased to 181 kcal. During this process, the cell control box displayed an impulse voltage of 2.56 V, and the current distribution on the anode showed a uniform state. Furthermore, other aluminum electrolysis cells in the series did not exhibit an anode effect due to the series current not reaching full current in a short time. Similar to Example 2, the aluminum electrolysis cells also achieved energy saving, improved conductivity, increased mechanical strength, and ensured high carbonization rate and stable physical properties during use.

[0192] Unlike the continuous anode assembly in Example 2, this continuous anode assembly has a large bottom area for each group of prebaked anodes, and the calcined petroleum coke particles laid on the upper surface of the cathode have a closer and more uniform contact with the bottom surface of each group of prebaked anodes, resulting in more uniform conduction of the series current. When the series current is uniformly conducted into the continuous anode assembly and even into the prebaked anode 2, the resistance heat generated by the series current through the prebaked anode 2 begins to further uniformly heat and raise the temperature of the prebaked anode 2. The prebaked anode 2 then further uniformly heats, melts, molds, and prebaks the anode paste 3 in contact with its surface. At this time, no additional energy is required to bake the anode paste, so energy is saved. For example, the impulse voltage is further reduced from 2.82V to 2.56V. At the same time, the carbonized anode paste 3 has a more uniform texture, better conductivity, and lower voltage drop.

[0193] Prebaked block and anode paste bonding experiment Experiment Example 1: Testing the bond strength between the anode paste and a prebaked block with grooves on its upper surface. A prebaked block with a diameter of 50 mm and a height of 60 mm was selected, with a bulk density of 1.62 g / cm³. 3 The resistivity is 53 μΩ·m, and the compressive strength is 42 MPa. Four slots, 5 mm deep and 5 mm wide, are pre-cut on the upper surface of the prebaked block in a "well" shape, with both ends of the slots connected to the perimeter of the prebaked block. Next, a 51 mm diameter, 300 mm high iron cylinder is placed in an alumina crucible, and the prebaked block is placed inside the iron cylinder with its upper surface facing upwards. Filler material is added around the iron cylinder and compacted. Anode paste particles, less than 15 mm in size, made from calcined petroleum coke and pitch, are then added to the iron cylinder, filling the upper surface of the prebaked block to a height of 180 mm. Cardboard, filler material, and an iron pillar are placed inside the iron cylinder above the anode paste. The alumina crucible, prebaked block, and anode paste are then transferred to an electric furnace, and the prebaked block and anode paste are roasted to 950 °C at a rate simulating the actual heating rate of an electrolytic cell and maintained for 3 hours. The sample consisting of the prebaked block and anode paste was removed from the electric furnace and alumina crucible and cooled to room temperature. The tensile strength between the prebaked block and the carbonized anode paste was then tested using a tensile testing machine. The composition of the added anode paste is shown in Table 1.

[0194] Table 1. Effect of different anolyte compositions on bond strength

[0195] Experiment Example 2: Testing the adhesion strength between the anode paste and a prebaked block with a smooth upper surface. A prebaked block with a diameter of 50 mm and a height of 60 mm was selected. The upper surface of the prebaked block was flat, dense, and without any bumps or depressions, and its bulk density was 1.62 g / cm³. 3The resistivity is 53 μΩ·m, and the compressive strength is 42 MPa. A 51 mm diameter, 300 mm high iron cylinder was placed in an alumina crucible. The prebaked block was placed inside the iron cylinder, and filler material was added around the cylinder and compacted. Anode paste particles, less than 15 mm in size, made from calcined petroleum coke and pitch, were then added to the iron cylinder, filling the upper surface of the prebaked block to a height of 180 mm. Cardboard, filler material, and an iron pillar were placed inside the iron cylinder above the anode paste. The alumina crucible, prebaked block, and anode paste were transferred to an electric furnace, and the prebaked block and anode paste were calcined to 950 °C at a rate simulating the actual heating rate of an electrolytic cell and held for 3 hours. The sample composed of the prebaked block and anode paste was removed from the electric furnace and alumina crucible and cooled to room temperature. The tensile strength between the prebaked block and the carbonized anode paste was tested using a tensile testing machine. The composition of the added anode paste is shown in Table 2.

[0196] Table 2. Effect of different anolyte compositions on bond strength

[0197] Although the embodiments of this application have been described above in conjunction with the accompanying drawings, this application is not limited to the specific embodiments and application fields described above. The specific embodiments described above are merely illustrative and instructive, not restrictive. Those skilled in the art can make many other forms based on the guidance of this specification and without departing from the scope of protection of the claims of this application, and these are all within the scope of protection of this application.

Claims

1. A continuous anode assembly, comprising: A metal frame having channels open at both ends; A prebaked anode, wherein the prebaked anode is sleeved in the channel of the metal frame and extends out of the metal frame, and the prebaked anode located in the channel has at least one slot. An anode paste, which fills the metal frame and contacts at least one surface of the prebaked anode, wherein the space containing the anode paste communicates with at least one of the slots; A conductor, which is assembled in at least one of the slots and / or the anode paste; the conductor is connected to the metal frame.

2. The continuous anode assembly according to claim 1, wherein the slotting includes a first slot and a second slot, the first slot communicating with the space where the anode paste is located; the second slot is used to assemble the conductor.

3. The continuous anode assembly according to claim 2, wherein the bottom end of the prebaked anode extends out of the metal frame, the anode paste fills the metal frame at the top of the prebaked anode, and the conductor is assembled in the second slot and the anode paste; When the prebaked anode comes into contact with the resistive layer, the bottom surface of the prebaked anode has an irregular shape.

4. The continuous anode assembly according to claim 1, wherein the continuous anode assembly comprises at least two prebaked anodes, each prebaked anode contacting the inner sidewall of the channel and forming an anode cavity between the prebaked anodes, the anode paste filling the anode cavity, and the conductor being assembled in the second slot.

5. The continuous anode assembly according to claim 1, wherein the prebaked anode is composed of at least one prebaked block, and at least one of the prebaked blocks has the slot; or the prebaked anode is replaced by a cathode carbon block.

6. The continuous anode assembly according to claim 5, wherein when there are two or more prebaked blocks, the prebaked blocks are connected by adhesive paste to form the prebaked anode.

7. The continuous anode assembly according to claim 6, wherein the binder paste comprises a carbon material and a binder.

8. The continuous anode assembly according to any one of claims 1 to 7, wherein the prebaked anode has a bulk density of 1.56 to 1.81 g / cm³. 3 Its resistivity is 36~56 μΩ·m and its compressive strength is 32~56MPa.

9. The continuous anode assembly according to any one of claims 1 to 7, wherein the anode paste comprises a carbon material and a binder; Preferably, the carbon material has a mass content of 71-79 wt%, and the binder has a mass content of 21-29 wt%.

10. The continuous anode assembly according to claim 9, wherein the carbon material is selected from one or more of petroleum coke, pitch coke, calcined petroleum coke, graphite and biomass.

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