A prebaked anode for aluminum electrolysis and preparation method thereof

Abstract

The present invention provides a prebaked anode for aluminum electrolysis and a preparation method thereof, and belongs to the technical field of electrode material production. The preparation method of the prebaked anode for aluminum electrolysis provided by the present invention comprises the following steps: placing a prebaked anode block for aluminum electrolysis in an impregnating agent for impregnation treatment to obtain an impregnated block; the impregnating agent is modified asphalt; the impregnated block is subjected to a first roasting to obtain a roasted block; the roasted blocks are assembled to obtain a prebaked anode for aluminum electrolysis. The present invention can increase the weight of the prebaked anode for aluminum electrolysis, increase its volume density, and reduce its porosity by performing an impregnation treatment and roasting on the prebaked anode block for aluminum electrolysis, thereby facilitating reducing its air permeability and improving its conductivity. During use, it has the advantages of low pressure drop, long pole replacement cycle, basically no carbon slag generation, and high current efficiency.

Description

Technical Field

[0001] The invention relates to the technical field of electrode material production, and in particular to a prebaked anode for aluminum electrolysis and a preparation method thereof. Background Art

[0002] Prebaked anodes for aluminum electrolysis play an important role in the aluminum electrolysis process, and their quality and working conditions have a great impact on technical and economic indicators such as energy consumption and product quality of aluminum electrolysis. The traditional preparation process of prebaked anodes for aluminum electrolysis mainly includes the following steps: forming the batched raw materials under the action of a binder to obtain a green block, baking the green block to obtain a cooked block, and assembling the cooked block to obtain a prebaked anode for aluminum electrolysis.

[0003] However, the prebaked anode for aluminum electrolysis prepared by the above-mentioned traditional process has the problem of short service life during actual use, and produces a large amount of electrolytic carbon slag. Summary of the invention

[0004] The object of the present invention is to provide a prebaked anode for aluminum electrolysis and a preparation method thereof. The prebaked anode for aluminum electrolysis prepared by the method provided by the present invention has a long service life and basically does not generate carbon slag during use.

[0005] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0006] The present invention provides a method for preparing a prebaked anode for aluminum electrolysis, comprising the following steps:

[0007] The prebaked anode block for aluminum electrolysis is placed in an impregnating agent for impregnation treatment to obtain an impregnated block; the impregnating agent is modified asphalt;

[0008] The impregnated cooked block is subjected to a first roasting to obtain a roasted cooked block;

[0009] The calcined blocks are assembled to obtain a prebaked anode for aluminum electrolysis.

[0010] Preferably, the temperature of the immersion treatment is 190-200° C., the pressure is 1.6 MPa, and the heat and pressure holding time is 5-6 hours.

[0011] Preferably, before the impregnation treatment, the process further comprises: preheating the prebaked anode block for aluminum electrolysis, wherein the preheating temperature is the temperature for the impregnation treatment.

[0012] Preferably, the temperature of the first calcination is 1180° C. and the holding time is 164 h.

[0013] Preferably, the temperature rising program for rising to the temperature of the first roasting includes: rising from room temperature to 875°C at a heating rate of 8°C / h, rising to 940°C at a heating rate of 6.5°C / h, rising to 1122°C at a heating rate of 7°C / h, rising to 1142°C at a heating rate of 5°C / h, rising to 1158°C at a heating rate of 4°C / h, and rising to the temperature of the first roasting at a heating rate of 2.75°C / h.

[0014] Preferably, the first calcination is performed in an air-tight condition.

[0015] Preferably, the method for preparing the prebaked anode block for aluminum electrolysis comprises the following steps:

[0016] The raw materials are mixed with a binder after batching, and subjected to a molding process to obtain a prebaked anode green block for aluminum electrolysis;

[0017] The prebaked anode green block for aluminum electrolysis is subjected to a second calcination to obtain a prebaked anode cooked block for aluminum electrolysis.

[0018] The present invention provides a prebaked anode for aluminum electrolysis prepared by the preparation method described in the above technical solution.

[0019] Preferably, the volume density of the prebaked anode for aluminum electrolysis is 1.59-1.61 g / cm 3 .

[0020] Preferably, the air permeability of the prebaked anode for aluminum electrolysis is 0.84-0.92npm, the air reactivity is 68.8-71.6%, the carbon dioxide reactivity is 87.3-92.1%, the compressive strength is 53-58MPa, the flexural strength is 4.21-4.40MPa, the resistivity is 55-57μΩ·m, and the thermal expansion coefficient is (4.21-4.40)×10 -6 K -1 , the ash content is 0.21~0.31%.

[0021] The present invention provides a method for preparing a prebaked anode for aluminum electrolysis, comprising the following steps: placing a prebaked anode block for aluminum electrolysis in an impregnating agent for impregnation treatment to obtain an impregnated block; the impregnating agent is modified asphalt; performing a first roasting on the impregnated block to obtain a roasted block; assembling the roasted blocks to obtain a prebaked anode for aluminum electrolysis. The present invention can increase the weight of the prebaked anode for aluminum electrolysis, increase its volume density, and reduce its porosity by performing an impregnation treatment and roasting on the prebaked anode block for aluminum electrolysis, thereby facilitating the reduction of its air permeability and improving its conductivity. During use, it has the advantages of low pressure drop, long pole replacement cycle, basically no carbon slag, and high current efficiency. At the same time, the prebaked anode for aluminum electrolysis prepared by the method of the present invention also has good oxidation resistance (high air reactivity).

[0022] In addition, the method provided by the present invention does not require special equipment and can be based on a traditional production line of electrode materials for aluminum electrolysis. It is also simple to operate and convenient for large-scale production. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a flow chart of preparing a prebaked anode for aluminum electrolysis in the embodiment;

[0024] Figure 2 This is a physical picture of hanging the prebaked anode block for aluminum electrolysis into the impregnation tank in Example 1;

[0025] Figure 3 This is a physical picture of preheating the prebaked anode block for aluminum electrolysis in Example 1;

[0026] Figure 4 This is a physical picture of the soaked cooked block in Example 1;

[0027] Figure 5 This is a physical picture of the calcined clinker and the guide rod being assembled and cast using molten iron in Example 1;

[0028] Figure 6 This is a physical picture of the residual anode obtained after using the prebaked anode for aluminum electrolysis prepared in Example 1 and Comparative Example 1. DETAILED DESCRIPTION

[0029] The present invention provides a method for preparing a prebaked anode for aluminum electrolysis, comprising the following steps:

[0030] The prebaked anode block for aluminum electrolysis is placed in an impregnating agent for impregnation treatment to obtain an impregnated block; the impregnating agent is modified asphalt;

[0031] The impregnated cooked block is subjected to a first roasting to obtain a roasted cooked block;

[0032] The calcined blocks are assembled to obtain a prebaked anode for aluminum electrolysis.

[0033] In the present invention, unless otherwise specified, the raw materials used are commercially available products well known to those skilled in the art.

[0034] The present invention first describes the method for preparing the prebaked anode block for aluminum electrolysis. In the present invention, the method for preparing the prebaked anode block for aluminum electrolysis preferably includes the following steps:

[0035] The raw materials are mixed with a binder after batching, and subjected to a molding process to obtain a prebaked anode green block for aluminum electrolysis;

[0036] The prebaked anode green block for aluminum electrolysis is subjected to a second calcination to obtain a prebaked anode cooked block for aluminum electrolysis.

[0037] The present invention mixes the raw materials with a binder after batching, and obtains prebaked anode green blocks for aluminum electrolysis through a molding process. In the present invention, the raw materials preferably include waste prebaked anode green blocks for aluminum electrolysis, calcined coke, and residual electrodes generated during aluminum electrolysis. The present invention preferably crushes and screens the raw materials independently in sequence to obtain raw materials of different particle sizes, which are used after batching. Specifically, the present invention preferably crushes and screens the waste prebaked anode green blocks for aluminum electrolysis in sequence to obtain raw crushed pieces, and the particle size of the raw crushed pieces is preferably 1 to 10 mm; crushes and screens the calcined coke in sequence to obtain coarse coke, medium coke, fine coke, and powdered coke, and the particle size of the coarse coke is preferably 5 to 8 mm, the particle size of the medium coke is preferably 3 to 5 mm, the particle size of the fine coke is preferably 1 to 3 mm, the particle size of the powdered coke is preferably less than 1 mm, and the powdered coke with a particle size less than 0.074 mm preferably accounts for 50 to 60% of the total mass of the powdered coke; the residual electrodes generated during aluminum electrolysis are crushed and screened in sequence to obtain raw crushed pieces, and the particle size of the raw crushed pieces is preferably 1 to 10 mm; crushes and screens the calcined coke in sequence to obtain coarse coke, medium coke, fine coke, and powdered coke, and the particle size of the coarse coke is preferably 5 to 8 mm, the particle size of the medium coke is preferably 3 to 5 mm, the particle size of the fine coke is preferably 1 to 3 mm, the particle size of the powdered coke is preferably less than 1 mm, and the powdered coke with a particle size less than 0.074 mm preferably accounts for 50 to 60% of the total mass of the powdered coke; The raw crushed coke, coarse coke, medium coke, fine coke, powdered coke, coarse residue and fine residue are preferably mixed in a certain proportion. Specifically, the mass ratio of the raw crushed coke, coarse coke, medium coke, fine coke, powdered coke, coarse residue and fine residue is preferably (4-8): (12-18): (15-22): (12-20): (35-42): (3-9): (3-9), and more preferably 8:14:18:16:38:7:7.

[0038] The present invention preferably preheats the batched raw materials, kneads the obtained preheated raw materials with a binder, and then sequentially cools and forms them to obtain prebaked anode green blocks for aluminum electrolysis. In the present invention, the preheating temperature is preferably 190-200°C; the binder is preferably modified asphalt; the mass ratio of the preheated raw materials to the binder is preferably 17:3. In the present invention, the cooling is preferably to cool the kneaded materials to 150-160°C; the cooling method is preferably water cooling. In the present invention, the molding treatment method is preferably vibration molding. In the present invention, the vibration molding conditions include: the molding pressure ratio is preferably 0.98kg / cm 2 The vibration time is preferably 45s.

[0039] After obtaining the prebaked anode green blocks for aluminum electrolysis, the present invention performs a second calcination on the prebaked anode green blocks for aluminum electrolysis to obtain prebaked anode cooked blocks for aluminum electrolysis. In the present invention, the conditions of the second calcination are consistent with the conditions of the subsequent first calcination, which will be described in detail later and will not be repeated here.

[0040] After obtaining the prebaked anode block for aluminum electrolysis, the present invention places the prebaked anode block for aluminum electrolysis in an impregnating agent for impregnation treatment to obtain an impregnated block. The present invention preferably preheats the prebaked anode block for aluminum electrolysis before impregnation treatment; the preheating temperature is preferably the impregnation treatment temperature; the preheating time is based on ensuring that the prebaked anode block for aluminum electrolysis meets the required temperature requirements both inside and outside. In the present invention, the impregnating agent is modified asphalt. In the present invention, the amount of the impregnating agent is based on ensuring that the prebaked anode block for aluminum electrolysis is completely immersed. In the present invention, the impregnation treatment temperature is preferably 190-200°C, specifically 190-193°C, 192-194°C, 192-195°C or 194-195°C; the pressure is preferably 1.6MPa; the heat preservation and pressure holding time is preferably 5-6h. The present invention preferably limits the temperature of the impregnation treatment to the above range, which is beneficial to making the impregnating agent have better fluidity. At the same time, the pressure of the impregnation treatment is limited to the above range, which is beneficial to ensure that the impregnating agent is absorbed as fully as possible into the pores of the prebaked anode block for aluminum electrolysis, thereby achieving a better impregnation effect.

[0041] The present invention preferably preheats the prebaked anode block for aluminum electrolysis to a target temperature, then immerses the prebaked anode block for aluminum electrolysis in an impregnating agent under vacuum conditions, pressurizes it to a target pressure, and performs the impregnation treatment while maintaining the temperature and pressure; the vacuum degree of the vacuum is preferably -0.08MPa. In an embodiment of the present invention, the impregnation treatment is specifically carried out in an impregnation tank, and the impregnating agent is stored in a paint storage tank, and the paint storage tank is connected to the impregnation tank by a solenoid valve; in actual production, the prebaked anode block for aluminum electrolysis is specifically hoisted into the impregnation tank, and then the prebaked anode block for aluminum electrolysis is preheated by using the heat medium system of the impregnation tank; after the prebaked anode block for aluminum electrolysis reaches the target temperature both inside and outside, the impregnation tank is evacuated to the target vacuum degree, the solenoid valve connecting the paint storage tank and the impregnation tank is opened, and the vacuum condition of the paint storage tank is used to allow the impregnating agent to enter the impregnation tank from the paint storage tank and completely immerse the prebaked anode block for aluminum electrolysis, and then the solenoid valve connecting the paint storage tank and the impregnation tank is closed, and the air compressor is started to pressurize the impregnation tank, and after reaching the target pressure, the temperature and pressure are maintained to the target time to complete the impregnation treatment.

[0042] After the impregnation treatment, the present invention preferably removes excess impregnating agent to obtain an impregnated cooked block. In an embodiment of the present invention, after the impregnation treatment is completed, the paint storage tank is evacuated, the solenoid valve connecting the paint storage tank and the impregnation tank is opened, and the vacuum condition of the paint storage tank is used to return excess impregnating agent from the impregnation tank to the paint storage tank, and then the obtained impregnated cooked block is lifted out of the impregnation tank.

[0043] After obtaining the impregnated cooked block, the present invention performs a first roasting on the impregnated cooked block to obtain a roasted cooked block. The present invention preferably cools the impregnated cooked block and then performs the first roasting. In the present invention, the temperature of the first roasting is 1180°C, and the holding time is preferably 164h. In the present invention, the temperature rising procedure for heating to the temperature of the first roasting preferably includes: heating from room temperature to 875°C at a heating rate of 8°C / h, heating to 940°C at a heating rate of 6.5°C / h, heating to 1122°C at a heating rate of 7°C / h, heating to 1142°C at a heating rate of 5°C / h, heating to 1158°C at a heating rate of 4°C / h, and heating to the temperature of the first roasting at a heating rate of 2.75°C / h. In the present invention, the first roasting is preferably carried out under air-tight conditions. In an embodiment of the present invention, the first roasting is preferably carried out in a 36-chamber roasting furnace. In the present invention, during the first roasting process, the impregnating agent in the impregnated cooked block is coked, thereby achieving the purpose of increasing the unit weight of the pre-baked anode for aluminum electrolysis, while being able to increase its volume density, reduce its porosity, and enhance its various performance indicators. The present invention preferably performs the first roasting under the above conditions, and can make full use of existing resources for manufacturing and production.

[0044] After the first roasting, the present invention preferably cleans the surface of the obtained carbon block, and then assembles the obtained roasted blocks to obtain a pre-baked anode for aluminum electrolysis. The present invention has no special limitation on the assembly, and a method familiar to those skilled in the art can be used. In an embodiment of the present invention, the roasted blocks are specifically assembled with guide rods, and then the assembled roasted blocks and guide rods are cast with molten iron, and after the surface is cleaned, a pre-baked anode for aluminum electrolysis is obtained, which can then be sent to an electrolytic cell for use.

[0045] The present invention provides a prebaked anode for aluminum electrolysis prepared by the preparation method described in the above technical solution.

[0046] In the present invention, the volume density of the prebaked anode for aluminum electrolysis is preferably 1.59 to 1.61 g / cm 3 In the present invention, the true density of the prebaked anode for aluminum electrolysis is preferably 2.06 g / cm 3 In the present invention, the air permeability of the prebaked anode for aluminum electrolysis is preferably 0.84 to 0.92 npm, the air reactivity is preferably 68.8 to 71.6%, the carbon dioxide reactivity is preferably 87.3 to 92.1%, the compressive strength is preferably 53 to 58 MPa, the flexural strength is preferably 4.21 to 4.40 MPa, the resistivity is preferably 55 to 57 μΩ·m, and the thermal expansion coefficient is (4.21 to 4.40)×10 -6 K -1 The ash content is preferably 0.21-0.31%.

[0047] The technical solutions in the present invention will be described clearly and completely below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0048] Comparative Example 1

[0049] The conventional process for preparing prebaked anodes for aluminum electrolysis is as follows:

[0050] Raw material batching: crushing and screening the pre-baked anode green blocks used for aluminum electrolysis in sequence to obtain raw crushed pieces (with a particle size of 1 to 10 mm); crushing and screening the calcined coke in sequence to obtain coarse coke (with a particle size of 5 to 8 mm), medium coke (with a particle size of 3 to 5 mm), fine coke (with a particle size of 1 to 3 mm) and powdered coke (with a particle size of less than 1 mm, and the powdered coke with a particle size of less than 0.074 mm accounts for 55% of the total mass of the powdered coke); crushing and screening the anode scraps produced during aluminum electrolysis in sequence to obtain coarse residues (with a particle size of 5 to 8 mm) and fine residues (with a particle size of 1 to 3 mm); mixing the components in a mass ratio of raw crushed pieces, coarse coke, medium coke, fine coke, powdered coke, coarse residues and fine residues of 8:14:18:16:38:7:7 to obtain a mixed raw material;

[0051] Molding process: the mixed raw material and the binder (specifically modified asphalt) are kneaded in a mass ratio of 17:3, and then molded to obtain a prebaked anode green block for aluminum electrolysis; wherein the molding process is vibration molding, and the molding specific pressure is 0.98kg / cm 2 , vibration time is 45s;

[0052] Calcination: placing the pre-baked anode green block for aluminum electrolysis in a 36-chamber calcining furnace, in an air-tight condition, heating from room temperature (25°C) to 875°C at a heating rate of 8°C / h, heating to 940°C at a heating rate of 6.5°C / h, heating to 1122°C at a heating rate of 7°C / h, heating to 1142°C at a heating rate of 5°C / h, heating to 1158°C at a heating rate of 4°C / h, heating to 1180°C at a heating rate of 2.75°C / h, and keeping the temperature for 164h; then taking out of the furnace, cleaning the surface of the obtained carbon block, and obtaining a calcined block;

[0053] Assembly: Assemble the prebaked anode block for aluminum electrolysis and the guide rod, then cast the assembled prebaked anode block for aluminum electrolysis and the guide rod with molten iron, and after surface cleaning, obtain the prebaked anode for aluminum electrolysis, which can then be sent to the electrolytic cell for use.

[0054] Two prebaked anodes for aluminum electrolysis were prepared repeatedly according to the method of Comparative Example 1, and were respectively recorded as Conventional Sample 1 and Conventional Sample 2.

[0055] Figure 1 The flowchart of preparing the prebaked anode for aluminum electrolysis in the embodiment is as follows. Figure 1 And embodiments are described in detail.

[0056] Examples 1 to 7

[0057] According to the method of Comparative Example 1, a prebaked anode block for aluminum electrolysis was prepared;

[0058] Dipping treatment: the prebaked anode block for aluminum electrolysis is hoisted into the dipping tank, and then the prebaked anode block for aluminum electrolysis is preheated by the heat medium system of the dipping tank; after the prebaked anode block for aluminum electrolysis reaches the target temperature (i.e., the dipping temperature) inside and outside, the dipping tank is evacuated for 15 minutes to the target vacuum degree (specifically -0.08MPa), the solenoid valve connecting the paint storage tank and the dipping tank is opened, and the vacuum condition of the paint dipping tank is used to allow the impregnating agent (specifically, modified asphalt) to enter from the paint storage tank. Put it into the impregnation tank and completely immerse the prebaked anode block for aluminum electrolysis, then close the solenoid valve connecting the paint storage tank and the impregnation tank, start the air compressor to pressurize the impregnation tank, and after reaching the target pressure (specifically 1.6MPa), keep the temperature and pressure to the target time to complete the impregnation process; then evacuate the paint storage tank, open the solenoid valve connecting the paint storage tank and the impregnation tank, use the vacuum condition of the paint storage tank to make the excess impregnating agent return from the impregnation tank to the paint storage tank, and then hang the obtained impregnated block out of the impregnation tank, cool it and set it aside;

[0059] Calcination: placing the impregnated cooked block in a 36-chamber calcining furnace, under air-tight conditions, heating from room temperature (25°C) to 875°C at a heating rate of 8°C / h, heating to 940°C at a heating rate of 6.5°C / h, heating to 1122°C at a heating rate of 7°C / h, heating to 1142°C at a heating rate of 5°C / h, heating to 1158°C at a heating rate of 4°C / h, heating to 1180°C at a heating rate of 2.75°C / h, and keeping warm for 164h; then taking out of the furnace, cleaning the surface of the obtained carbon block, and obtaining a calcined cooked block;

[0060] Assembly: The calcined blocks are assembled according to the method of comparative example 1 to obtain prebaked anodes for aluminum electrolysis, which can then be sent to an electrolytic cell for use.

[0061] Some of the operating conditions in Examples 1 to 7 are listed in Table 1.

[0062] Table 1 Part of the operating conditions in Examples 1 to 7

[0063]

[0064]

[0065] According to the method in YS / T63, the prebaked anodes for aluminum electrolysis prepared in Examples 1 to 4 and Comparative Example 1 were subjected to index detection and performance testing, wherein the prebaked anodes for aluminum electrolysis prepared in Examples 1 to 4 were respectively recorded as high-density samples 1 to 4, and the specific results are shown in Table 2.

[0066] Table 2 Index detection and performance test results of prebaked anodes for aluminum electrolysis in Examples 1 to 4 and Comparative Example 1

[0067]

[0068]

[0069] It can be seen from Table 1 and Table 2 that, compared with the prebaked anode for aluminum electrolysis of the same specification produced by the traditional process, after the method provided by the present invention is used for impregnation treatment and roasting, the weight of a single block of the prebaked anode for aluminum electrolysis is increased by 45 to 56 kg, and the volume density, compressive strength, flexural strength and air reactivity are improved, and the air permeability is reduced, thereby enhancing the physical and chemical properties of the prebaked anode for aluminum electrolysis.

[0070] The prebaked anodes for aluminum electrolysis prepared in the examples and comparative examples were installed in electrolytic cells for aluminum electrolysis. The results showed that the prebaked anodes for aluminum electrolysis prepared in the conventional method in comparative example 1 had a service life of 36 days and carbon slag (such as Figure 6 As shown on the right); and in Example 1, the prebaked anode for aluminum electrolysis prepared by adding secondary impregnation and secondary roasting steps on the basis of the traditional method has a service life of 40 days, which greatly reduces the labor intensity of electrolysis employees, and the average voltage is reduced by 0.006V during operation, and the current efficiency is improved by 1.05%. After 40 days of stable operation, the regularity of the residual anode is maintained well, there is no bottom collapse or clawing phenomenon, and there is basically no carbon slag in the tank, which has the effect of avoiding the need to remove carbon slag (such as Figure 6 shown on the left).

[0071] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for preparing a prebaked anode for aluminum electrolysis, comprising the following steps: The prebaked anode block for aluminum electrolysis is placed in an impregnating agent for impregnation treatment to obtain an impregnated block; the impregnating agent is modified asphalt; the impregnation treatment temperature is 190-200°C, the pressure is 1.6MPa, and the heat preservation and pressure holding time is 5-6h; The impregnated cooked block is subjected to a first roasting to obtain a roasted cooked block; the first roasting temperature is 1180° C., and the heat preservation time is 164 hours; The calcined blocks are assembled to obtain a prebaked anode for aluminum electrolysis.

2. The preparation method according to claim 1, characterized in that: Before the impregnation treatment, the method further includes: preheating the prebaked anode block for aluminum electrolysis, and the preheating temperature is the temperature for the impregnation treatment.

3. The preparation method according to claim 1, characterized in that: The heating program for heating to the temperature of the first calcination includes: heating from room temperature to 875°C at a heating rate of 8°C / h, heating to 940°C at a heating rate of 6.5°C / h, heating to 1122°C at a heating rate of 7°C / h, heating to 1142°C at a heating rate of 5°C / h, heating to 1158°C at a heating rate of 4°C / h, and heating to the first calcination temperature at a heating rate of 2.75°C / h.

4. The preparation method according to claim 1 or 3, characterized in that: The first calcination is performed in an air-tight condition.

5. The preparation method according to claim 1, characterized in that: The method for preparing the prebaked anode block for aluminum electrolysis comprises the following steps: The raw materials are mixed with a binder after batching, and subjected to a molding process to obtain a prebaked anode green block for aluminum electrolysis; The prebaked anode green block for aluminum electrolysis is subjected to a second calcination to obtain a prebaked anode cooked block for aluminum electrolysis.

6. A prebaked anode for aluminum electrolysis prepared by the preparation method according to any one of claims 1 to 5.

7. The prebaked anode for aluminum electrolysis according to claim 6, characterized in that: The volume density of the prebaked anode for aluminum electrolysis is 1.59-1.61 g / cm 3 .

8. The prebaked anode for aluminum electrolysis according to claim 6 or 7, characterized in that: The prebaked anode for aluminum electrolysis has an air permeability of 0.84-0.92 npm, an air reactivity of 68.8-71.6%, a carbon dioxide reactivity of 87.3-92.1%, a compressive strength of 53-58 MPa, a flexural strength of 4.21-4.40 MPa, a resistivity of 55-57 μΩ·m, and a thermal expansion coefficient of (4.21-4.40)×10 -6 K -1 , the ash content is 0.21~0.31%.

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