High-density homogeneous green anode carbon block dynamic formula and forming parameter optimization method

Abstract

The invention discloses a high-density homogeneous green anode carbon block dynamic formula and a forming parameter optimization method, belongs to the technical field of electrolytic aluminum carbon, and aims to solve the problems that control indexes in a green anode formula and a manufacturing process are too simple, and the quality of a prebaked anode cannot be well controlled and improved. The method comprises the following steps: analyzing the quality of calcined coke for raw anode carbon block burdening; the method is suitable for dynamic formula technology laboratory research of different raw material conditions; quickly analyzing the quality condition of the calcined coke and establishing a feedback system; analyzing the viscosity of the asphalt; and performing a kneading forming process parameter optimization test. According to the method, multi-factor and all-around technology and process research are integrated, the key technology for producing the high-density homogeneous green anode from related raw materials is broken through, high-density homogenization of the green anode volume density index is achieved, the quality of the green anode is remarkably improved, the problem that the volume density of the green anode is not uniform due to quality fluctuation of calcined coke is solved, and the method is pioneered in the industry and has wide application prospects. And the practical value is extremely high.

Description

Technical Field

[0001] This invention belongs to the field of electrolytic aluminum carbon technology, specifically relating to a dynamic formulation and molding parameter optimization method for high-density homogeneous green anode carbon blocks. Background Technology

[0002] Prebaked anodes play a crucial role in the continuous energy supply to the aluminum electrolysis cell during aluminum electrolysis production. High-quality prebaked anodes possess excellent physicochemical and electrochemical properties, low impurity content, and uniform and stable quality, effectively improving the economic and technical indicators of aluminum electrolysis. Using high-quality prebaked anodes results in a more stable production process, higher current efficiency, better environmental conditions, lower labor intensity for workers, and favorable key technical and economic indicators. Conversely, inferior prebaked anodes are characterized by cracks, fractures, low strength, high porosity, high resistivity, poor chemical resistance and electrochemical performance, high ash content, and easy detachment. Cracks in prebaked anodes can cause them to crumble during use, altering current distribution, reducing current efficiency, and causing severe slag shedding. Slag shedding affects the stable operation of the electrolysis cell, increases labor intensity for workers, and also has adverse environmental impacts.

[0003] In the production of prebaked anodes, the quality of the green anode has a crucial impact on the overall quality of the prebaked anode. The green anode manufacturing process involves crushing or grinding carbon raw materials into particles of different sizes, mixing them with liquid asphalt in a specific ratio to form a plastic paste, and then extruding or vibrating it to produce carbon blocks with a certain strength and density. Because prebaked anode technology requires the green anode carbon blocks to be roasted at a high temperature of 1100-1200℃ to remove volatiles and coke the asphalt, thereby improving the mechanical strength and conductivity of the product, the anode that has not been roasted after molding is called a green anode.

[0004] Currently, international and domestic quality indicators for prebaked anodes are all for the calcined anodes. In actual production, the quality control of green anodes can only be carried out from two aspects: volume density and appearance. However, through long-term tracking, monitoring and research, our company has found that the formula and manufacturing process of green anodes directly affect the performance indicators of prebaked anodes, such as volume density, conductivity, strength and oxidation resistance. The influencing factors that our company has identified, such as the selection of formula, the accuracy of batching, the purity of grinding, the purity of sieving, the mixing effect and the molding technical parameters, directly determine the quality of prebaked anode carbon blocks.

[0005] Further research and experiments on the above factors revealed that, among the parameters, the quality of the carbon plant's self-produced calcined coke is relatively stable due to the large proportion of calcined coke in the formula. However, the quality of the purchased calcined coke, which is used to make up for the lack of self-production, fluctuates greatly due to changes in manufacturers and batches. This factor is the core element leading to the low volume density and large quality fluctuation of the green anode.

[0006] Based on the problems mentioned above, researchers have proposed a method for optimizing the dynamic formulation and molding parameters of high-density homogeneous green anode carbon blocks. Summary of the Invention

[0007] The purpose of this invention is to provide a dynamic formulation and molding parameter optimization method for high-density homogeneous green anode carbon blocks, so as to solve the problem that the control indicators in the green anode formulation and manufacturing process are too simple and cannot effectively control and improve the quality of prebaked anodes.

[0008] To solve the above problems, the technical solution of the present invention is as follows: A method for optimizing the dynamic formulation and molding parameters of high-density homogeneous green anode carbon blocks, which specifically includes the following steps: S1. Quality analysis of calcined coke used in the preparation of raw anode carbon blocks; The raw materials of calcined coke taken from the production site were subjected to a series of analyses, including trace elements, ash content, volatile matter, tap density analysis, powder resistivity analysis, and air and carbon dioxide reactivity analysis. Based on the analysis results, the differences and patterns of various indicators between the calcined coke produced on-site and the calcined coke purchased from different manufacturers were obtained, providing a basis for orthogonal experiments on the formulation. S2. Laboratory research on dynamic formulation technology adapted to different raw material conditions; S2.1 Orthogonal test of calcined coke formulation; Based on the on-site production formula and material purity fluctuations, orthogonal experiments were conducted using self-produced calcined coke and purchased calcined coke respectively. Orthogonal experimental design was used to design different proportions of coarse coke, fine coke, coke powder, coarse residue, fine residue, and medium coke. Then, experiments were conducted according to the proportions, and the results were summarized to obtain the trend of the relationship between the formula ratio, dosage and tap density under the same formula; this provides a basis for dynamic formulation of different raw materials. S2.2, Dynamic Recipe Establishment; Based on the orthogonal experimental results in S2.1, a dynamic formulation for different raw materials was established; During the production process, the workshop samples and sieves materials of each particle size in real time, fills in the sieving data results and the current working formula in a table, and calculates the particle size composition of the mixture after the current formula is implemented. It is then compared with the empirical target value. If there is a large deviation, the proportion of each particle size needs to be modified in the working formula column until the calculated result of the mixture matches the target value, which is the optimal working formula at this time. S3. Establishment of a rapid analysis and feedback system for the quality status of calcined coke; In conjunction with the dynamic formulation of S2, after formulating an optimized blending scheme for calcined coke, relevant analysis and testing equipment is installed on-site to provide timely feedback on various performance indicators of self-produced calcined coke, purchased calcined coke, and blending indicators. S4. Asphalt viscosity analysis; A series of index analyses were conducted on the asphalt used in the production of raw anode carbon blocks, including coking value; toluene insoluble matter, quinoline insoluble matter, β resin; and the corresponding values ​​of asphalt viscosity and temperature. The coking value is used to determine whether asphalt meets the requirements for Grade A grade. Whether it is beneficial to improve anode strength and resistivity can be determined by examining the levels of toluene-insoluble matter, quinoline-insoluble matter, and β-resin. The optimal mixing temperature and mold placement temperature are determined by the corresponding values ​​of asphalt viscosity and temperature. S5. Optimization test of kneading molding process parameters; The most important parameters in the kneading molding process include the compacted density of coke after rotary kiln calcination, the purity of ball mill powder, the speed of the vibration molding motor, the temperature of the dry molding material, and the temperature of the paste entering the mold. S5.1 Optimization of coke compaction density after rotary kiln calcination; The tertiary air of the rotary kiln for calcination was adjusted through experiments to track the change law of coke tap density after calcination; the results of the optimization index analysis of coke tap density after calcination in the rotary kiln were plotted into an intuitive and visual line graph, and the calcination zone was moved forward or backward according to the experimental results. S5.2 Optimization of ball mill powder purity; The purity of the ball milled powder (60%±5%) is based on 91.5%, and it is best to maintain a stable level above this benchmark. This technical indicator is achieved by quantitatively feeding the dust-collecting powder and matching the feeding time of the dust-collecting powder and the granular material. S5.3 Optimization of vibration molding machine control process; The change data of green bulk density index before and after speed adjustment were collected by experiment, and a line graph of vibration motor speed adjustment was plotted. At the same time, it was found that the green bulk density index was more stable in which speed range, and the motor speed was fixed in this range. S5.4 Molding production system process parameters optimization; Observe the molding production dry material temperature and paste mold entry temperature shown in the production monitoring data, and adjust them to the optimal kneading temperature and mold entry temperature determined in S4.

[0009] Furthermore, the performance data of the self-produced calcined coke, purchased calcined coke, and mixed indicators mentioned in section 3 include S, V, Na, Si, Fe, Ca, and Ni.

[0010] Furthermore, the S3 calcined coke adopts a one-belt-three-compartment blending method. Specifically, the one-belt-three-compartment method refers to: a single conveyor belt transports three types of materials in different time periods through the system, and the materials are mixed on the belt. The self-produced calcined coke, purchased calcined coke, and mixed coke are stored in three separate compartments, and are precisely blended according to demand when used.

[0011] Furthermore, the asphalt viscosity and temperature values ​​described in S4 are plotted as an asphalt viscosity-temperature curve to determine the optimal kneading temperature and mold placement temperature.

[0012] The beneficial effects of this invention are as follows: (1) This invention systematically studies the quality characteristics of calcined coke through laboratory-scale dynamic formulation experiments, providing theoretical basis and data support for industrial production; by constructing a rapid analysis and feedback mechanism for the quality status of calcined coke, a rapid response system (within 2 hours) is established from sampling and testing to data feedback. This system can realize real-time monitoring and early warning of key indicators of calcined coke, provide data information support for dynamic formulation, improve the timeliness and accuracy of quality control, and realize real-time monitoring and adjustment of quality problems in the production process; simultaneously, dynamic formulation experiments of green anodes are carried out in the actual industrial production environment to verify the feasibility and applicability of laboratory research results.

[0013] By determining the appropriate temperature range for asphalt during kneading and molding, process conditions can be optimized; by analyzing key parameters such as viscosity, kneading and molding process parameters can be further optimized to improve production efficiency and product quality.

[0014] This invention integrates multi-factor and comprehensive technical and process research, breaking through key technologies in the production of high-density homogeneous green anodes from related raw materials. It achieves high-density homogeneity in the green anode volume density, significantly improving green anode quality and solving the problem of uneven green anode volume density caused by fluctuations in the quality of calcined coke. This is a first in the industry. The overall technical route started from laboratory research and gradually progressed to industrial trials and process optimization, forming a complete technical system from theory to practice, from analysis to feedback. It fills a gap in this technological field and has extremely high practical value.

[0015] (2) This invention addresses the problem of low bulk density of green anodes due to large fluctuations in the quality of calcined coke in our company's feedstock. It improves the compacted bulk density of self-produced calcined coke through calcination process optimization, improves the mixing of calcined coke in three bins on a single conveyor belt, rapidly analyzes and provides feedback on the quality of calcined coke, and develops and applies dynamic formulation technology, thus forming a high-density homogeneous green anode production technology. In particular, it fully utilizes existing equipment conditions in the mixing of calcined coke, proposing and implementing a "one belt, three bins" refined mixing process for calcined coke. This allows for the time-segmented transport of three materials using a single conveyor belt system, with materials mixed on the belt. Self-produced calcined coke, purchased calcined coke, and mixed coke are stored in three separate bins, and mixed precisely according to demand. The invention also proposes concepts such as "no mixing and no use of calcined coke, staggered material processing to reduce peak and valley loads," significantly reducing the particle size and composition fluctuations of calcined coke, improving the homogeneity of raw materials, and providing a stable material basis for the production of high-density homogeneous green anodes. Attached Figure Description

[0016] Figure 1This is a technical roadmap for the present invention; Figure 2 The image shows the asphalt viscosity-temperature curve plotted in S4 of Example 1. Figure 3 The graph shows the tap density of coke after calcination in the rotary kiln in S5.1 of Example 1. Figure 4 The graph shows the speed adjustment of the vibration motor in S5.3 of Example 1. Figure 5 This is a third-party testing report on the volume density of the prepared green anode in Example 2; Figure 6 This is the second third-party testing report on the volume density of the prepared green anode in Example 2. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] Therefore, the following detailed description of embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention.

[0019] Example 1 A method for optimizing the dynamic formulation and molding parameters of high-density homogeneous green anode carbon blocks, the main technical route of which is as follows: Figure 1 As shown, it is divided into two main parts: the first is to realize the industrial application test of dynamic formulation green anode technology through the quality analysis of calcined coke used in green anode block formulation, laboratory research on dynamic formulation adapted to different raw material conditions, and the establishment of a rapid analysis and feedback system for the quality of calcined coke; the second is to determine the appropriate temperature range for asphalt kneading and molding through asphalt viscosity analysis, so as to optimize the kneading and molding process parameters; through the optimization of dynamic formulation and process parameters, the high-density homogeneous production technology of green anode blocks is achieved and improved.

[0020] This method specifically consists of the following steps: S1. Quality analysis of calcined coke used in the preparation of raw anode carbon blocks; A series of analyses were conducted on the calcined coke raw materials taken from the production site, and the results are shown in Tables 1-1 to 1-4.

[0021] Table 1-1 Micro-element analysis results of calcined coke used in the preparation of raw anode carbon blocks Table 1-2 Analysis results of calcined coke ash, volatile matter and tap density of raw anode carbon blocks. Table 1-3 Resistivity analysis results of calcined coke powder used in the preparation of raw anode carbon blocks. Table 1-4 Results of Air and Carbon Dioxide Reactivity Analysis of Calcinated Coke Used in Raw Anode Carbon Block Batching According to the analysis results in Tables 1-1 to 1-4: (1) Tap density of self-produced calcined coke (0.7 g / cm³) 3 The density of the sample was significantly lower than that of the purchased coke tap density (0.822 g / cm³). 3 When the purchased calcined coke cannot be uniformly added to the production process and is mixed with self-produced calcined coke, the bulk density of the green billet will fluctuate significantly.

[0022] (2) The S and V content of self-produced calcined coke is slightly higher than that of purchased calcined coke.

[0023] (3) The resistivity of the powder of self-produced calcined coke is higher than that of the powder of purchased coke.

[0024] (4) The air reaction rate of self-produced calcined coke is lower than that of purchased calcined coke.

[0025] S2. Laboratory research on dynamic formulation technology adapted to different raw material conditions; S2.1 Orthogonal test of calcined coke formulation; Based on the on-site production formula and material purity fluctuations, orthogonal experiments were conducted using both self-produced calcined coke and purchased calcined coke. The results are shown in Tables 1-5 to 1-7.

[0026] Table 1-5 Orthogonal Experiment Formula Table 1-6 Results of Orthogonal Formulation Experiment Table 1-7 Results of the orthogonal experiment As shown in Tables 1-5 to 1-7, under the same formula: The bulk density of purchased coke is much higher than that of self-produced coke. As the proportion of coarse coke decreases, the compaction density of the formula increases; As the amount of fine coke and powder increases, the compaction density of the formula increases.

[0027] S2.2, Dynamic Recipe Establishment; Based on the orthogonal experimental results in S2.1, dynamic formulations for different raw materials are established.

[0028] During the production process, the workshop samples and sieves materials of each particle size in real time, and fills the sieving data results and the current working formula in Table 2-1. The particle size composition of the mixture after the current formula is implemented is calculated and compared with the target value (the theoretical formula of the best bulk density summarized from experience). If there is a large deviation, the proportion of each particle size needs to be modified in the working formula column until the calculated result of the mixture matches the target value, which is the optimal working formula at this time.

[0029] This process involves dynamically adjusting the production formula.

[0030] The dynamic formulation results in this embodiment are shown in Table 2-1: Table 2-1 Dynamic Formulation Results .

[0031] S3. Establishment of a rapid analysis and feedback system for the quality status of calcined coke; In conjunction with the dynamic formulation of S2, an optimized blending scheme for calcined coke was developed. In this embodiment, blending schemes were designed for the 400kA and 200kA series respectively.

[0032] This step requires the availability of relevant analytical and testing equipment on-site to provide timely data feedback.

[0033] The relevant equipment is shown in Table 3-1: Table 3-1 List of Analytical and Testing Equipment Purchased calcined coke for 400kA production is unloaded by a tipper and placed into a calcined coke silo for separate storage. It is then mixed with self-produced calcined coke at a ratio of 1:1 (single source) or 2:1:1 (Hualu, Yixing) into the production system. The indicators after mixing are shown in Table 3-2. Table 3 - Mixing Schemes for the 2400kA Series 200kA is produced using Hualu and Yixing coke, either from a single source or in a 1:1 ratio of Hualu and Yixing coke into the molding production system; the indicators after mixing are shown in Table 3-3. Table 3-3200kA Series Mixing Schemes After calcined coke is blended, the three materials are transported in time intervals by a single conveyor belt using existing equipment. The materials are mixed on the belt. The self-produced calcined coke, purchased calcined coke, and mixed coke are stored in three separate silos. When used, they are blended precisely according to the required proportions.

[0034] S4. Asphalt viscosity analysis; A series of index analyses were conducted on the asphalt used for the production of raw anode carbon blocks from the production site. The results are shown in Tables 4-1 and 4-3.

[0035] Table 4-1 Analysis Results of Asphalt Coking Value Index Table 4-2 Results of Asphalt Component Content Analysis Table 4-3 Corresponding values ​​of asphalt viscosity and temperature As shown in Tables 4-1 and 4-2, the asphalt index is relatively good, with a coking value of 58.5%, which meets the requirements of Grade I product; the β resin index of 20.3% is also good, which is beneficial to the improvement of anode strength, resistivity and other indicators.

[0036] Based on experience, the optimal kneading temperature is when the asphalt viscosity is 300~600cp, and the optimal temperature for vibratory molding paste to be poured into the mold is when the asphalt viscosity is 1000~3000cp. According to Table 7, the kneading temperature for this type of asphalt should be around 190~200℃; the optimal temperature for vibratory molding paste to be poured into the mold should be 162~178℃.

[0037] The asphalt viscosity and temperature data from Table 4-3 are plotted as asphalt viscosity-temperature curves for easy and intuitive study. Figure 2 As shown.

[0038] S5. Optimization test of kneading molding process parameters; The most important parameters in the kneading molding process include the compacted density of the coke after calcination in the rotary kiln, the purity of the ball mill powder, the speed of the vibration molding motor, the temperature of the dry material being molded, and the temperature of the paste entering the mold.

[0039] S5.1 Optimization of coke compaction density after rotary kiln calcination; The tertiary air of the rotary kiln was adjusted through experiments to track the change in the tap density of the calcined coke. During the experiment, samples of the calcined coke from the rotary kiln were taken every 2 hours, and the tap density index of the calcined coke was analyzed in a timely manner. The results are shown in Table 5-1: Table 5-1 Analysis Results of Optimization Indicators for Coke Tap Density After Calcination in Rotary Kiln The results of the optimized index analysis of coke tap density after rotary kiln calcination were plotted into an intuitive and visual line graph, such as... Figure 3 As shown in the figure: the test results show that as the calcination zone moves forward, the density of the coke after calcination tends to increase, and the tertiary air parameters can be appropriately increased in production.

[0040] S5.2 Optimization of ball mill powder purity; In the original production process, the grooving powder and the dust collected by the crushing system jointly entered a dust collection silo, which continuously fed the mill during production. However, because the grooving powder contains some fine powder (with a content of about 25%, and the content is unstable), and the grooving powder enters the silo in a short-term concentrated feeding method, the material composition in the silo varies greatly at different times. Furthermore, the discharge device at the bottom of the silo lacks frequency conversion control and operates at full speed, causing large fluctuations in the fine powder content of the material entering the mill. This results in significant fluctuations in the purity of the mill's powder, exceeding 14%, which seriously interferes with the mill operators' judgment of the ball mill powder quality and subsequent adjustment measures. This will make it difficult to stably control the asphalt mix ratio in the molding production, and cause significant fluctuations in the quality of the green body.

[0041] Based on the site conditions, the original continuous and variable feeding of dust collection powder was changed to quantitative feeding of dust collection powder, and the mismatch between the feeding time of dust collection powder and granular material was changed to matched feeding. These measures achieved uniform particle size distribution in the ball mill feed and stabilized the purity of the powder.

[0042] In November, the purity of ball milled powder (60%±5%) accounted for 93.3%, and remained stable.

[0043] S5.3 Optimization of vibration molding machine control process; In the original production control process, due to fluctuations in the density of calcined coke and the purity of ball milled powder, the vibration molding machine operator would adjust the speed of the vibration molding machine according to the bulk density of the green billet and the crack situation. The adjustment was relatively frequent, in order to make up for the impact of fluctuations in the previous process.

[0044] However, the rotational speed of the vibration molding machine is one of the most critical parameters. Changes in rotational speed will lead to changes in the vibration force of the molding machine, and will affect the uniformity of material dispersion within the mold, as well as the homogeneity of the anode. Such arbitrary, experience-based operation can easily overlook quality issues in previous processes and adversely affect quality control throughout the production process.

[0045] This embodiment collects data on the changes in the bulk density of the green billet before and after speed adjustment through experiments, and plots a line graph of the vibration motor speed adjustment as shown below. Figure 4 As shown in the figure, among the above rotational speeds, the bulk density of the green billet is more stable in the range of 1100-1200 r / min.

[0046] When the aforementioned formula and process change, the optimal speed of the vibration molding machine can be determined by adjusting the motor speed and then solidified to eliminate quality fluctuations caused by the randomness of experience-based operations.

[0047] Simultaneously, in terms of quality management, the authority to adjust the molding machine speed has been elevated to the workshop management level, preventing frontline employees from making arbitrary modifications to ensure the reliability of the solidification process.

[0048] S5.4 Molding production system process parameters optimization; Before optimization, the production monitoring data in this embodiment showed that the temperature of the dry material during molding was around 155°C, and the temperature of the paste entering the mold was around 140°C.

[0049] Of these two temperature parameters, the dry material temperature and the paste pouring temperature are both too low, which is detrimental to improving anode quality. Increasing the paste pouring temperature is beneficial for increasing the anode bulk density and also for homogenizing the anode quality.

[0050] Based on the asphalt viscosity test index in S4, the mixing temperature in the molding workshop was adjusted to 190~200℃, and the mold entry temperature was adjusted to 162~178℃. The quality of the paste was improved.

[0051] Example 2 1. Industrial application test of the dynamic formulation and molding parameter optimization method for green anode carbon blocks in Example 1: During the experiment, using the method of Example 1, the molding process collected materials of each particle size three times a day for sieving. Based on the sieving results and formula calculation, the particle size composition of the dry material mixture in the actual production process was calculated and compared with the summarized optimal bulk density formula. The proportion of each particle size material was adjusted appropriately to make it conform to or approach the theoretical formula of optimal dry material bulk density (similar to Table 2-1, dynamic adjustment was made).

[0052] During industrial trial applications, statistical analysis of the bulk density of the original green billets produced by the molding machine showed that the density ranged from 1.63 to 1.66 g / cm³ from January to March 2025. 3 The proportion of raw anode carbon blocks within the range is 96.3%. Due to the large amount of data, some original records and statistics are shown in Table 1.

[0053] Table 1. Bulk Density and Statistics of Original Green Billets for Molding Machines After sampling and testing the bulk density of the green anode, the average bulk density of the green anode was found to be 1.642 g / cm³. 3 Compared to 1.624 g / cm³ in the first 1-3 months before project implementation. 3 Increased by 0.018 g / cm³ 3 The bulk density of the green body is greater than 1.63 g / cm³. 3 It accounts for 95.81%.

[0054] Table 2 shows some of the original record data and statistical results.

[0055] Table 2. Bulk Density and Statistics of Raw Anodes 2. Application test evaluation indicators and completion status: Assessment indicator 1: Average volume density of green anodes ≥ 1.64 g / cm³ 3 Over 95% of the green bodies have a bulk density greater than 1.63 g / cm³. 3 (Subject to laboratory analysis results) Completion Status: Laboratory analysis results from January to March 2025 showed an average anode bulk density of 1.642 g / cm³. 3 Compared to 1.624 g / cm³ in January-March 2024 before the project implementation. 3 Increased by 0.018 g / cm³ 3 The bulk density of the green body is greater than 1.63 g / cm³. 3 It accounts for 95.81%.

[0056] Assessment Indicator 2: Monthly anode bulk density of 95% or higher is 1.63~1.66 g / cm³ 3 Within the specified range. (Based on the automatic measurement data of the molding machine at the production site, excluding start-up anode blocks and abnormal anode blocks) Completion status: From January to March 2025, the bulk density was between 1.63 and 1.66 g / cm³. 3 The proportion of raw anode carbon blocks within the scope was 96.30%, which is double the 46.1% in the first three months before the project was implemented.

[0057] The green anode was sampled and its bulk density was tested by a qualified third-party testing institution. The test report is available here. Figure 5 and Figure 6 .

[0058] visible: 1. The average bulk density of the green anodes produced by Lanzhou Aluminum Industry is 1.645 g / cm³. 3 The bulk density of the raw anode is greater than 1.63 g / cm³. 3 The proportion is 95.83%. The measured value of the raw anode volume density is consistent with the test results of Lanzhou Aluminum Industry Laboratory.

[0059] 2. This study verifies that the dynamic formulation and molding parameter optimization method for green anode carbon blocks established in Example 1 of this invention can indeed improve the quality of prebaked anodes and achieve the production goal of high-density homogeneous anodes.

Claims

1. A method for optimizing the dynamic formulation and molding parameters of high-density homogeneous green anode carbon blocks, characterized in that, This method specifically consists of the following steps: S1. Quality analysis of calcined coke used in the preparation of raw anode carbon blocks; The raw materials of calcined coke taken from the production site were subjected to a series of analyses, including trace elements, ash content, volatile matter, tap density analysis, powder resistivity analysis, and air and carbon dioxide reactivity analysis. Based on the analysis results, the differences and patterns of various indicators between the calcined coke produced on-site and the calcined coke purchased from different manufacturers were obtained, providing a basis for orthogonal experiments on the formulation. S2. Laboratory research on dynamic formulation technology adapted to different raw material conditions; S2.1 Orthogonal test of calcined coke formulation; Based on the on-site production formula and material purity fluctuations, orthogonal experiments were conducted using self-produced calcined coke and purchased calcined coke respectively. Orthogonal experimental design was used to design different proportions of coarse coke, fine coke, coke powder, coarse residue, fine residue, and medium coke. Then, experiments were conducted according to the proportions, and the results were summarized to obtain the trend of the relationship between the proportion and dosage of the formula and the tapped density under the same formula. It provides a basis for dynamic formulation of different raw materials; S2.2, Dynamic Recipe Establishment; Based on the orthogonal experimental results in S2.1, a dynamic formulation for different raw materials was established; During the production process, the workshop samples and sieves materials of each particle size in real time, fills in the sieving data results and the current working formula in a table, and calculates the particle size composition of the mixture after the current formula is implemented. It is then compared with the empirical target value. If there is a large deviation, the proportion of each particle size needs to be modified in the working formula column until the calculated result of the mixture matches the target value, which is the optimal working formula at this time. S3. Establishment of a rapid analysis and feedback system for the quality status of calcined coke; In conjunction with the dynamic formulation of S2, after formulating an optimized blending scheme for calcined coke, relevant analysis and testing equipment is installed on-site to provide timely feedback on various performance indicators of self-produced calcined coke, purchased calcined coke, and blending indicators. S4. Asphalt viscosity analysis; A series of index analyses were conducted on the asphalt used in the production of raw anode carbon blocks, including coking value; toluene insoluble matter, quinoline insoluble matter, β resin; and the corresponding values ​​of asphalt viscosity and temperature. The coking value is used to determine whether asphalt meets the requirements for Grade A grade. Whether it is beneficial to improve anode strength and resistivity can be determined by examining the levels of toluene-insoluble matter, quinoline-insoluble matter, and β-resin. The optimal mixing temperature and mold placement temperature are determined by the corresponding values ​​of asphalt viscosity and temperature. S5. Optimization test of kneading molding process parameters; The most important parameters in the kneading molding process include the compacted density of coke after rotary kiln calcination, the purity of ball mill powder, the speed of the vibration molding motor, the temperature of the dry molding material, and the temperature of the paste entering the mold. S5.1 Optimization of coke compaction density after rotary kiln calcination; The tertiary air of the rotary kiln for calcination was adjusted through experiments to track the change law of coke tap density after calcination; the results of the optimization index analysis of coke tap density after calcination in the rotary kiln were plotted into an intuitive and visual line graph, and the calcination zone was moved forward or backward according to the experimental results. S5.2 Optimization of ball mill powder purity; The purity of the ball milled powder (60%±5%) is based on 91.5%, and it is best to maintain a stable level above this benchmark. This technical indicator is achieved by quantitatively feeding the dust-collecting powder and matching the feeding time of the dust-collecting powder and the granular material. S5.3 Optimization of vibration molding machine control process; The change data of green bulk density index before and after speed adjustment were collected by experiment, and a line graph of vibration motor speed adjustment was plotted. At the same time, it was found that the green bulk density index was more stable in which speed range, and the motor speed was fixed in this range. S5.4 Molding production system process parameters optimization; Observe the molding production dry material temperature and paste mold entry temperature shown in the production monitoring data, and adjust them to the optimal kneading temperature and mold entry temperature determined in S4.

2. The method for optimizing the dynamic formulation and molding parameters of high-density homogeneous green anode carbon blocks as described in claim 1, characterized in that, The performance data of the self-produced calcined coke, purchased calcined coke, and mixed indicators mentioned in S3 include S, V, Na, Si, Fe, Ca, and Ni.

3. The method for optimizing the dynamic formulation and molding parameters of high-density homogeneous green anode carbon blocks as described in claim 2, characterized in that, S3 uses a one-belt-three-compartment blending system for calcined coke. Specifically, the one-belt-three-compartment system means that a single conveyor belt transports three types of materials in different time periods. The materials are mixed on the belt. Self-produced calcined coke, purchased calcined coke, and mixed coke are stored in three separate compartments. When used, they are blended precisely according to the required proportions.

4. The method for optimizing the dynamic formulation and molding parameters of high-density homogeneous green anode carbon blocks as described in claim 3, characterized in that, The asphalt viscosity and temperature values ​​described in S4 are plotted as an asphalt viscosity-temperature curve to determine the optimal kneading temperature and mold placement temperature.

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