Process and device for refining aluminum ingot by using aluminum ash

Abstract

The invention relates to the technical field of aluminum ash refining, in particular to an aluminum ingot refining technology and device using aluminum ash, and the technology comprises the steps that the aluminum ash on the surface of molten aluminum-silicon alloy is introduced into a slag pan to be naturally cooled; crushing and ball-milling the cooled aluminum ash, obtaining aluminum ash samples according to a preset time interval in the ball-milling process, sieving the aluminum ash samples, and obtaining mass ratio vectors and all particle size sets of the aluminum ash samples at all moments according to mass distribution of the sieved aluminum ash samples; obtaining the particle size distribution uniformity of the aluminum ash sample at each moment; acquiring an aluminum separation evaluation coefficient of the aluminum ash sample at each moment; obtaining an evaluation coefficient difference sequence and an aluminum separation threshold value of the aluminum ash sample at each moment as a stop judgment condition of ball milling of the aluminum ash; and after ball milling is stopped, all the aluminum ash residues are sieved, the aluminum ash residues with the preset particle size range are selected for high-temperature smelting, and the aluminum ingots are obtained. The aluminum ingot refining device aims at reducing impurities of aluminum ingots and improving the aluminum ingot refining quality.

Description

Technical Field

[0001] The present application relates to the technical field of aluminum ash slag refining, and specifically to a process and device for refining aluminum ingots using aluminum ash slag. Background Art

[0002] During the melting and alloying process of aluminum, the molten aluminum encounters an oxidizing atmosphere and oxidation occurs on the surface, resulting in the formation of a semi-solid skin on the molten metal. This mixture is called aluminum slag, which is mainly composed of alumina, metallic aluminum, magnesium spinel, periclase, quartz and salts containing small amounts of aluminum carbides and aluminum nitrides. Aluminum slag is inevitably produced in aluminum smelters, and there are usually two types of aluminum slag: white slag (primary aluminum slag) and black slag (secondary aluminum slag). White slag is formed during the primary production of aluminum and contains a high percentage of aluminum substances, such as Al and Al2O3; black slag contains a small amount of metal substances and is produced during the secondary aluminum refining process.

[0003] Smelters use aluminum ash slag as raw materials to refine aluminum ingots and other products. Among them, one of the commonly used methods is to use thermal metallurgy to release the liquid metal aluminum in it for aluminum ingot refining. The thermal metallurgical method of refining aluminum ingots requires the aluminum ash slag to be ground and pre-treated first to facilitate the subsequent melting of aluminum. At present, the process flow of refining aluminum ingots by thermal metallurgy does not take into account the differences in the impact of mechanical treatment during ball milling on particles of different components of aluminum ash slag, resulting in a lower degree of enrichment of metallic aluminum in the aluminum ash slag involved in the melting, causing an increase in impurities in the aluminum ingots, affecting the quality of aluminum ingot refining. Summary of the invention

[0004] In view of the above, it is necessary to provide an aluminum ingot refining process and device using aluminum ash slag to solve the above problems.

[0005] In a first aspect, the present application provides an aluminum ingot refining process using aluminum ash slag, the method comprising: Step 1, introducing aluminum ash slag on the surface of the molten aluminum-silicon alloy into a slag pan for natural cooling; Step 2, crushing and ball milling the cooled aluminum ash slag, obtaining and sieving aluminum ash slag samples at preset time intervals during the ball milling process, and obtaining the mass ratio vector of the aluminum ash slag samples at each moment and all particle size sets according to the mass distribution of the aluminum ash slag samples after sieving; Step 3, according to the discrete degree of elements in all particle size sets corresponding to the aluminum ash slag samples at each moment, the particle size distribution uniformity of the aluminum ash slag samples at each moment is obtained; according to the similarity of the mass ratio vector of the aluminum ash slag samples obtained at each moment and the moment before the ball milling process, combined with the degree of change of the particle size distribution uniformity, the aluminum separation evaluation coefficient of the aluminum ash slag samples at each moment is obtained; Step 4, analyzing the change characteristics of the aluminum separation evaluation coefficient of the aluminum ash slag samples at each moment and the previous moment during the ball milling process, obtaining the evaluation coefficient difference sequence of the aluminum ash slag samples at each moment and the aluminum separation threshold value as the stopping judgment condition of the ball milling of the aluminum ash slag; after stopping the ball milling, sieving all the aluminum ash slag and selecting the aluminum ash slag within the preset particle size range; Step 5, high-temperature smelting the selected aluminum ash slag to obtain aluminum ingots.

[0006] Preferably, the cooling atmosphere for natural cooling is argon, and the cooling time is 12 to 24 hours.

[0007] Preferably, the specific operation of ball milling is: the mass of aluminum ash slag during ball milling is , the speed of the ball mill is 30~40 rpm.

[0008] Preferably, the specific process of obtaining the mass ratio vector of the aluminum ash slag sample at each moment and all particle size sets is: During the ball milling process, a preset mass of aluminum ash slag samples are taken out at each time, and the aluminum ash slag samples at the same time of ball milling are screened into a preset number of portions through a multi-layer linear vibrating screen, and the mass of each portion of aluminum ash slag sample is weighed and arranged in order from large to small according to the average particle size; Obtain the mass ratio of each aluminum ash slag sample as an element of the mass ratio vector of the aluminum ash slag sample at each moment; The mass of each aluminum ash slag sample and the mass of a preset number of subsequent aluminum ash slag samples are set as each particle size set.

[0009] Preferably, the process of obtaining the particle size distribution uniformity of the aluminum ash slag sample at each moment is: For the aluminum ash slag samples at each moment, the negative correlation mapping results of the discreteness of the elements in each particle size set are calculated, and the negative correlation mapping results are weighted and summed using the preset weight value of each particle size set to obtain the particle size distribution uniformity of the aluminum ash slag samples at each moment.

[0010] Preferably, the formula for obtaining the aluminum separation evaluation coefficient of the aluminum ash slag sample at each moment is: ;in, represents the aluminum separation evaluation coefficient of the aluminum ash sample at the i-th moment, represents the difference in particle size distribution uniformity of the aluminum ash slag sample at the i-th moment and the i-1-th moment; exp() represents an exponential function with a natural constant as the base; , Respectively represent the mass ratio vector of the aluminum ash slag sample at the i-th moment and the i-1-th moment; represents the cosine similarity function; is a parameter that is preset to be greater than zero.

[0011] Preferably, the evaluation coefficient difference sequence and aluminum separation threshold of the aluminum ash slag samples at each moment are obtained as follows: The sequence of aluminum separation evaluation coefficients of aluminum ash slag samples at each moment and a set number of moments before is recorded as an evaluation sequence; the difference sequence of the evaluation sequence at each moment is recorded as the evaluation coefficient difference sequence at each moment; The mean of all elements in the evaluation coefficient difference sequence at each moment is recorded as the aluminum separation threshold.

[0012] Preferably, the specific process of the stop determination condition of the ball milling of aluminum ash slag is: If the last element value of the evaluation coefficient difference sequence of the aluminum ash slag sample at the current moment is greater than the aluminum separation threshold at the current moment, the ball milling of the aluminum ash slag is stopped.

[0013] Preferably, the particle size of the selected aluminum ash slag is greater than 1.25 mm, and a plasma arc method is used for high-temperature smelting, the smelting temperature is 700-800° C., and the smelting time is 1-2 h.

[0014] In the second aspect, an embodiment of the present application also provides an aluminum ingot refining device using aluminum ash slag, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, wherein the processor implements any of the above-mentioned steps of an aluminum ingot refining process using aluminum ash slag when executing the computer program.

[0015] This application has at least the following beneficial effects: The embodiment of the present application adopts dry ball milling to avoid the reaction between aluminum ash slag and water and reduce pollution. By real-time detection of the mass distribution of aluminum ash slag with different particle sizes in the ball mill, the separation degree of non-metallic phase particles and metallic aluminum phase particles in different batches of aluminum ash slag is analyzed: first, the mass ratio vector and particle size set of the aluminum ash slag samples at each moment in the ball milling process are obtained to provide a data basis for the subsequent analysis of the mass distribution of aluminum ash slag with different particle sizes; the element distribution in the particle size set is analyzed to obtain the uniformity of the particle size distribution, which helps to comprehensively reflect the mass distribution of aluminum ash slag in different particle size ranges; the aluminum separation evaluation coefficient of the aluminum ash slag sample at each moment is obtained, and its beneficial effect is to characterize the metal phase of the aluminum ash slag during the ball milling process. The degree of separation from the non-metallic phase; the evaluation coefficient difference sequence of the aluminum ash slag samples at each moment and the aluminum separation threshold are obtained, which has the beneficial effect of accurately judging the degree of separation between the metal phase and the non-metallic phase in the aluminum ash slag, controlling the ball milling time, increasing the content of metallic aluminum in the aluminum ash slag after screening, reducing the impurities introduced into the aluminum ingot during the high-temperature melting process, and improving the refining quality of the aluminum ingot; finally, the plasma arc method is used to melt the primary aluminum ash slag, using the plasma arc as the external heat source, without the need to add additional salt flux, reducing the impurity content in the molten aluminum, and avoiding the smoke pollution generated by salt impurities in a high-temperature environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A flowchart of a process for refining aluminum ingots using aluminum ash slag provided in one embodiment of the present application; Figure 2 A schematic diagram of the process flow for refining aluminum ingots provided in one embodiment of the present application. DETAILED DESCRIPTION

[0017] In the description of the embodiments of the present application, words such as "exemplary", "or", "for example" and the like are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary", "or", "for example" and the like is intended to present related concepts in a concrete manner.

[0018] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art in the present application. The terms used in the specification of the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application.

[0019] It should also be noted that the terms "first" and "second" in this application and the accompanying drawings are used to distinguish similar objects, rather than to describe a specific order or sequence. The method disclosed in the embodiments of the present application or the method shown in the flow chart includes one or more steps for implementing the method. Without departing from the scope of protection of the present application, the execution order of multiple steps can be interchanged with each other, and some steps can also be deleted.

[0020] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

[0021] The specific scheme of the aluminum ingot refining process and device using aluminum ash slag provided in the present application is described in detail below with reference to the accompanying drawings.

[0022] Example 1 See also Figure 1 , which shows a flow chart of the steps of an aluminum ingot refining process using aluminum ash slag provided in Example 1 of the present application, the process comprising the following steps: Step 1: introduce the aluminum ash slag on the surface of the molten aluminum silicon alloy into a slag pan for natural cooling.

[0023] This application uses the primary aluminum ash slag formed on the surface of the molten metal when producing 4000 series aluminum silicon alloy as raw material to refine aluminum ingots. In the melting process of producing 4000 series aluminum silicon alloy, the aluminum liquid easily reacts with oxygen and nitrogen in the air to generate aluminum oxide and aluminum nitride. Aluminum oxide and aluminum nitride are insoluble in aluminum liquid and float on the surface of aluminum liquid to become aluminum ash slag. In the reverberatory furnace for producing aluminum silicon alloy, the aluminum ash slag on the surface of the molten aluminum silicon alloy is introduced into the slag pan. It should be noted that the aluminum ash slag volume scraped out to the slag pan accounts for 80% of the volume of the slag pan to avoid excessive loading and overflow of the aluminum ash slag.

[0024] During the slag removal process, the aluminum ash slag inevitably encloses a certain amount of liquid metal aluminum and enters the slag pan. In order to avoid further oxidation of the metal aluminum in the aluminum ash slag, the present application adopts an inert gas protection cooling method to naturally cool the aluminum ash slag in the slag pan. The cooling atmosphere uses argon gas and the cooling time is 12 hours.

[0025] Step 2: crush and ball-mill the cooled aluminum ash slag. During the ball-milling process, aluminum ash slag samples are obtained and sieved at preset time intervals. According to the mass distribution of the sieved aluminum ash slag samples, the mass ratio vector of the aluminum ash slag samples at each moment and the set of all particle sizes are obtained.

[0026] A hammer crusher is used to fully crush the cooled aluminum ash slag, and the crushed aluminum ash slag and grinding steel balls are sent to a ball mill, wherein the mass of the steel balls is twice the mass of the aluminum ash slag. The speed of the ball mill is set to 30 rpm, and the ball mill is started to ball-mill the aluminum ash slag to facilitate the subsequent high-temperature smelting of metallic aluminum. After the ball mill is turned on, the discharge port of the ball mill is opened at a predetermined time interval, and 1 kg of the crushed aluminum ash slag sample is taken and sent to a multi-layer linear vibrating screen. In this application, the multi-layer linear vibrating screen is provided with a total of 5 layers of sieves, and the sieve hole sizes are 10 mm, 4 mm, 2 mm, 1.25 mm, and 1 mm, respectively. Aluminum ash slag with different particle sizes after screening enters different material boxes respectively, the mass of the aluminum ash slag in 6 material boxes is weighed, and the ratio thereof to the total mass of the aluminum ash slag weighed before screening is calculated respectively, and recorded as the mass ratio of the aluminum ash slag in the material boxes with different particle sizes. The mass ratios of the 6 material boxes are arranged in sequence from small to large in the order of the number of layers passing through the multi-layer linear vibrating screen, that is, in the order of large to small average particle size, to form a mass ratio vector, which is used to reflect the mass distribution of aluminum ash slag with different particle sizes in the aluminum ash slag sample; it is convenient for subsequent analysis of the change of the reference mass ratio vector with the ball milling time, and to obtain the influence of mechanical treatment on particles of different components of this batch of aluminum ash slag during the ball milling process.

[0027] During the pretreatment of aluminum slag, the aluminum alloy production process is carried out many times. Due to the different feed ingredients in different production processes, the degree of oxidation of the molten metal aluminum is different, resulting in different batches of aluminum slag components. Considering the differences in the mechanical treatment of particles of different components of aluminum slag during ball milling and the fluctuations in the proportion of components of different batches of aluminum slag, it is difficult to determine a fixed ball milling time. If the ball milling time is too short, the separation degree of the metal aluminum phase and the non-metal phase is low, and too many impurities are introduced during melting; if the ball milling time is too long, the particle size of the metal aluminum phase particles is small, and the utilization rate of the aluminum slag is reduced.

[0028] In the crushed aluminum ash, the metal aluminum is usually wrapped by a film of aluminum oxide and aluminum nitride. Since the metal phase of aluminum has high ductility, it is not easy to be crushed into smaller particles. The non-metallic phase of aluminum oxide, aluminum nitride and silicon dioxide is relatively hard and fragile, and can be easily crushed into smaller particles.

[0029] The content of metallic aluminum in primary aluminum ash slag is relatively high, and the content of metallic aluminum in the crushed aluminum ash slag decreases with the decrease of particle size. Therefore, the aluminum ash slag samples obtained in the early stage of ball milling are mostly concentrated in the material box with larger particle size; in the early stage of ball milling, the particle size of non-metallic phase particles changes rapidly with the increase of ball milling time. The larger non-metallic phase particles are crushed into smaller particles under the mechanical action of steel balls, thereby changing the mass distribution of aluminum ash slag with different particle sizes; the particle size of metallic aluminum particles changes slowly with the increase of ball milling time, and the mass distribution of metallic aluminum particles with different particle sizes does not change significantly.

[0030] When the degree of separation between the metallic aluminum phase particles and the non-metallic phase particles is high, the ball mill will grind or break the metallic aluminum that is difficult to grind, resulting in a reduction in the mass of the metallic aluminum phase particles with a larger particle size. In addition, due to the higher proportion of metallic aluminum content in the primary aluminum ash, the distribution of particle sizes in different particle size ranges becomes more uniform.

[0031] Taking into account the differences in the mechanical effects on the particle sizes of non-metallic phase particles and metallic aluminum phase particles, in order to more accurately determine the separation state of aluminum ash slag in the ball mill, M particle size sets are constructed, where M is 4. The specific construction method is as follows: obtain the mass of aluminum ash slag samples in each particle size range, and take the mass of aluminum ash slag in each particle size range and the mass of aluminum ash slag in a preset number of subsequent particle size ranges as each particle size set.

[0032] In this embodiment, the preset number is 2. Specifically, the mass of aluminum ash slag with a particle size less than 1 mm is recorded as a; the mass of aluminum ash slag with a particle size between 1 and 1.25 mm is recorded as b; the mass of aluminum ash slag with a particle size between 1.25 and 2 mm is recorded as c; the mass of aluminum ash slag with a particle size between 2 and 4 mm is recorded as d; the mass of aluminum ash slag with a particle size between 4 and 10 mm is recorded as e; the mass of aluminum ash slag with a particle size greater than 10 mm is recorded as f; the set consisting of a, b, and c is recorded as the first particle size set; the set consisting of b, c, and d is recorded as the second particle size set; the set consisting of c, d, and e is recorded as the third particle size set, and the set consisting of d, e, and f is recorded as the fourth particle size set.

[0033] Step 3, according to the degree of discreteness of elements in all particle size sets corresponding to the aluminum ash slag samples at each moment, obtain the uniformity of particle size distribution of the aluminum ash slag samples at each moment; according to the similarity of the mass ratio vector of the aluminum ash slag samples obtained at each moment and the moment before the ball milling process, combined with the degree of change of the particle size distribution uniformity, obtain the aluminum separation evaluation coefficient of the aluminum ash slag samples at each moment.

[0034] The larger the particle size of the aluminum ash slag in the particle size set, the higher the content of metallic aluminum. When the degree of separation between the metallic aluminum phase particles and the non-metallic phase particles is high, the steel balls in the ball mill begin to act on the metallic aluminum, and the particle size change of the aluminum ash slag in the corresponding particle size set is more obvious. In order to stop the ball milling in time when the metallic aluminum phase particles and the non-metallic phase particles are separated, a larger weight is set for the mass ratio standard deviation of the material box in the particle size set with a larger particle size, so as to improve the subsequent detection effect when the mass distribution of the aluminum ash slag in the particle size set with a larger particle size changes. The calculation weights of the first particle size set, the second particle size set, the third particle size set, and the fourth particle size set are set to be respectively , , , , in this embodiment, the values ​​are 0.1, 0.2, 0.3, and 0.4 respectively; and .

[0035] According to the mass ratio of the material boxes in different particle size sets, the uniformity of the particle size distribution of the aluminum ash slag is calculated: the negative correlation mapping results of the discreteness of the elements in each particle size set are calculated, and the negative correlation mapping results are weighted and summed with the preset weight value of each particle size set to obtain the uniformity of the particle size distribution of the aluminum ash slag.

[0036] In this embodiment, the standard deviation is used to measure the discreteness of all elements of each particle size set; the opposite number of the discreteness is used as the exponent of an exponential function with a natural constant as the base, and the exponential function is used as the negative correlation mapping result of the discreteness.

[0037] It should be understood that the larger the standard deviation of the elements in each particle size set, the smaller the uniformity of the particle size distribution; the uniformity of the particle size distribution of aluminum ash slag is used to comprehensively reflect the mass distribution of aluminum ash slag in different particle size ranges.

[0038] The mass distribution of aluminum ash slag with different particle sizes changes differently at different stages of ball milling. In the early stage of ball milling, the steel balls in the ball mill mainly act on the non-metallic phase particles. Since the mass proportion of non-metallic phase particles in the primary aluminum ash slag is small, and their particle sizes are concentrated in a smaller particle size range, the calculated particle size distribution uniformity does not change much. When the degree of separation between the metal aluminum phase particles and the non-metallic phase particles is high, the particle size of the metal aluminum phase particles begins to decrease, the mass of the aluminum ash slag in the small particle size range increases, and the mass in the large particle size range decreases, thereby increasing the uniformity of the particle size distribution. At the same time, the similarity between the mass ratio vectors of the two adjacent aluminum ash slag samples is smaller.

[0039] According to the degree of change of the mass ratio vector of the aluminum ash sample at different times of ball milling, the aluminum separation evaluation coefficient is calculated, and its formula is as follows: ;in, represents the aluminum separation evaluation coefficient of the aluminum ash sample at the i-th moment, represents the difference in particle size distribution uniformity of the aluminum ash slag sample at the i-th moment and the i-1-th moment; exp() represents an exponential function with a natural constant as the base, the purpose is to Mapped to positive values; , Respectively represent the mass ratio vector of the aluminum ash slag sample at the i-th moment and the i-1-th moment; represents the cosine similarity function; The value is 2, the purpose is to map the cosine similarity to a positive value, where , implementers can choose the value according to actual conditions; the aluminum separation evaluation coefficient is used to reflect the degree of separation of metallic aluminum phase and non-metallic phase particles in aluminum ash slag. The higher the degree of separation between the two, the greater the calculated aluminum separation evaluation coefficient.

[0040] Step 4, analyzing the change characteristics of the aluminum separation evaluation coefficient of the aluminum ash slag samples at each moment and before the ball milling process, and obtaining the evaluation coefficient difference sequence of the aluminum ash slag samples at each moment and the aluminum separation threshold as the stopping judgment condition of the ball milling of the aluminum ash slag; after stopping the ball milling, sieve all the aluminum ash slag and select the aluminum ash slag within the preset particle size range.

[0041] The aluminum ash slag samples taken out at the previous t moments are used as references. When the aluminum ash slag samples are taken out, the sequence of aluminum separation evaluation coefficients of the aluminum ash slag samples at the current moment and the aluminum ash slag samples at the previous t moments in chronological order is recorded as the evaluation sequence at the current moment, and the differential sequence of the evaluation sequence at the current moment is calculated and recorded as the evaluation coefficient differential sequence. In this embodiment, t is taken as 3. When the number of aluminum separation evaluation coefficients is less than t, linear interpolation is used to supplement it. The linear interpolation method is an existing well-known technology and will not be described in detail in this application.

[0042] In the early stage of ball milling, the non-metallic phase particles gradually separate from the metallic aluminum phase under the mechanical action of the ball mill, the aluminum separation evaluation coefficient increases, and the value of the corresponding evaluation coefficient difference sequence continues to increase. As the two continue to separate, the growth rate of the aluminum separation evaluation coefficient gradually decreases, and the value of the corresponding evaluation coefficient difference sequence gradually decreases; when the degree of separation between the two is large, the increase rate of the aluminum separation evaluation coefficient becomes significantly faster. The main reason is that the ball mill mainly acts on the metallic aluminum phase particles at this time, which rapidly increases the uniformity of the particle size distribution of the aluminum ash slag, and the particle size mass distribution changes rapidly between two adjacent times. At this time, turn off the ball mill to prevent the metallic aluminum from being ball-milled into finer particles, and increase the content of metallic aluminum in the aluminum ash slag after screening.

[0043] The average value of all values ​​in the evaluation coefficient difference sequence is recorded as the aluminum separation threshold, which reflects the average change in the degree of separation between the metal aluminum phase and the non-metal phase in the t moments before the aluminum ash slag sample was taken out. The last value of the evaluation coefficient difference sequence represents the change in the degree of separation between the metal aluminum phase and the non-metal phase in the aluminum ash slag samples at two adjacent moments.

[0044] As the ball milling time increases, the growth rate of the aluminum separation evaluation coefficient decreases, and the evaluation coefficient difference sequence becomes smaller and smaller. Before the steel balls in the ball mill begin to act on the metal aluminum phase particles, the end value of the evaluation coefficient difference sequence does not exceed the aluminum separation threshold. The end value of the evaluation coefficient difference sequence is greater than the aluminum separation threshold, reflecting that the separation degree of the metal aluminum phase and the non-metal phase in the ball mill is high at this time, and the ball mill begins to act on the metal aluminum phase particles. At this time, the ball mill is turned off to complete the ball milling of aluminum ash slag.

[0045] The aluminum ash slag in the ball mill passes through the above-mentioned multi-layer linear vibrating screen and flows into different material boxes to obtain aluminum ash slag with different particle sizes. Since the metal aluminum phase particles in the aluminum ash slag after ball milling are significantly larger than the non-metal phase particles, the aluminum ash slag with a particle size greater than 1.25mm is taken out of the material box for subsequent treatment.

[0046] Step 5, high-temperature smelting the selected aluminum ash slag to obtain aluminum ingots.

[0047] The taken out aluminum ash slag is loaded into a plasma arc rotary furnace, the plasma torch is installed on the charging door of the rotary furnace, and the plasma torch is turned on for high temperature smelting.

[0048] Air or nitrogen is introduced between the two electrodes of the plasma torch, and the electrodes conduct electricity to generate an arc, which partially ionizes the gas to generate plasma, and heats the aluminum ash slag in the rotary furnace to 800°C. The aluminum ash slag melts in the atmosphere of the heated gas, and at the same time, the plasma arc rotary furnace rotates, and under mechanical stirring, the oxide film breaks and the metal aluminum gathers.

[0049] After 2 hours of high-temperature smelting, the molten aluminum is separated from the non-metallic phase products in the aluminum ash. The molten aluminum is poured out from the loading door by tilting the plasma arc rotary furnace to complete the refining of the aluminum ingot.

[0050] Among them, the process flow diagram of aluminum ingot refining is as follows Figure 2 shown.

[0051] Example 2 See also Figure 1 , which shows a flow chart of the steps of an aluminum ingot refining process using aluminum ash slag provided in Example 2 of the present application, the process comprising the following steps: Step 1, adopt the same process as step 1 of Example 1 to obtain cooled aluminum ash slag; wherein the cooling time is 24 hours.

[0052] Step 2, using the same process as step 2 of Example 1, obtain the mass ratio vector of the aluminum ash slag sample at each moment and all particle size sets; wherein the mass of the aluminum ash slag during ball milling is the mass of the steel balls in the ball mill. , the speed of the ball mill is 40 rpm.

[0053] Step 3, using the same process as step 3 of Example 1, obtain the aluminum separation evaluation coefficient of the aluminum ash slag sample at each time.

[0054] Step 4, adopting the same process as step 4 of Example 1, selecting aluminum ash slag with a particle size greater than 2 mm; Step 5, adopting the same process as step 5 of Example 1 to obtain an aluminum ingot; wherein the temperature for high-temperature smelting is 700°C, and the time for high-temperature smelting is 2 hours.

[0055] Example 3 See also Figure 1 , which shows a flow chart of the steps of an aluminum ingot refining process using aluminum ash slag provided in Example 3 of the present application, the process comprising the following steps: Step 1, adopt the same process as step 1 of Example 1 to obtain cooled aluminum ash slag; wherein the cooling time is 18 hours.

[0056] Step 2, using the same process as step 2 of Example 1, obtain the mass ratio vector of the aluminum ash slag sample at each moment and all particle size sets; wherein the mass of the aluminum ash slag during ball milling is the mass of the steel balls in the ball mill. , the speed of the ball mill is 40 rpm.

[0057] Step 3, using the same process as step 3 of Example 1, obtain the aluminum separation evaluation coefficient of the aluminum ash slag sample at each time.

[0058] Step 4, adopting the same process as step 4 of Example 1, selecting aluminum ash slag with a particle size greater than 4 mm; Step 5, adopting the same process as step 5 of embodiment 1 to obtain an aluminum ingot; wherein the temperature for high-temperature smelting is 800°C, and the time for high-temperature smelting is 1 hour.

[0059] Comparative Example 1 The ball milling time of Comparative Example 1 was 6 h, and the other parameters were kept consistent with those of Example 1 to obtain an aluminum ingot.

[0060] Comparative Example 2 The ball milling time of Comparative Example 2 was 9 h, and the other parameters were consistent with those of Example 2 to obtain an aluminum ingot.

[0061] Comparative Example 3 The ball milling time of Comparative Example 3 was 12 h, and the other parameters were consistent with those of Example 3 to obtain an aluminum ingot.

[0062] Finally, the aluminum ingots refined at different ball milling times were analyzed by XRD using a Zeiss Ultra 55 scanning electron microscope (SEM) combined with energy dispersive X-ray spectroscopy (EDS), and the aluminum content in the aluminum ingots under different embodiments and comparative examples and the mass ratio of the aluminum ingots to the aluminum ash slag were obtained as shown in the following table: Examples 1, 2, and 3 show that as the particle size of the smelting aluminum ash increases, the aluminum content in the refined aluminum ingot gradually increases, but the aluminum content in the aluminum ash with a particle size greater than 4 mm does not increase significantly compared to that of the aluminum ash with a particle size greater than 2 mm, and the utilization rate of the aluminum ash decreases significantly.

[0063] Example 1 and Comparative Example 1 as well as Example 2 and Comparative Example 2 show that the ball milling time of Comparative Example 1 is too short, and the metallic aluminum phase and the non-metallic phase cannot be separated to a large extent, resulting in a high impurity content in the aluminum ingot.

[0064] Example 3 and Comparative Example 3 show that as the ball milling time increases, the aluminum content in the refined aluminum ingot in the comparative example increases, but the ball milling time of Comparative Example 3 is too long, so that too much metal aluminum phase particles are screened out, resulting in a decrease in the utilization rate of aluminum ash slag.

[0065] Based on the same inventive concept as the above method, an embodiment of the present application also provides an aluminum ingot refining device using aluminum ash slag, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, wherein when the processor executes the computer program, any step in the above-mentioned aluminum ingot refining process using aluminum ash slag is implemented.

[0066] The flowchart and block diagram in the accompanying drawings show the possible architecture, function and operation of the system, method and computer program product according to the embodiment of the present application. In this regard, each box in the flowchart or block diagram can represent a module, a program segment or a part of the code, and the module, the program segment or a part of the code contains one or more executable instructions for realizing the specified logical function. In some alternative implementations, the function marked in the box can also occur in a different order from the order marked in the accompanying drawings. For example, two continuous boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, which can depend on the functions involved. In the description corresponding to the flowchart and the block diagram in the accompanying drawings, the operations or steps corresponding to different boxes can also occur in a different order from the order disclosed in the description, and sometimes there is no specific order between different operations or steps. For example, two continuous operations or steps can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, which can depend on the functions involved. Each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, may be implemented by a dedicated hardware-based system that performs the specified functions or actions, or may be implemented by a combination of dedicated hardware and computer instructions.

[0067] For those skilled in the art, it is obvious that the present application is not limited to the details of the above exemplary embodiments, and the present application can be implemented in other specific forms without departing from the basic features of the present application. Therefore, no matter from which point of view, the above embodiments of the present application should be regarded as exemplary and non-restrictive; the technical solutions recorded in the above embodiments are modified, or some of the technical features are replaced by equivalents, which does not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and should be included in the protection scope of the present application.

Claims

1. A process for refining aluminum ingots using aluminum ash slag, characterized in that: The process includes the following steps: Step 1, introducing aluminum ash slag on the surface of the molten aluminum-silicon alloy into a slag pan for natural cooling; Step 2, crushing and ball milling the cooled aluminum ash slag, obtaining and sieving aluminum ash slag samples at preset time intervals during the ball milling process, and obtaining the mass ratio vector of the aluminum ash slag samples at each moment and all particle size sets according to the mass distribution of the aluminum ash slag samples after sieving; Step 3, according to the discrete degree of elements in all particle size sets corresponding to the aluminum ash slag samples at each moment, the particle size distribution uniformity of the aluminum ash slag samples at each moment is obtained; according to the similarity of the mass ratio vector of the aluminum ash slag samples obtained at each moment and the moment before the ball milling process, combined with the degree of change of the particle size distribution uniformity, the aluminum separation evaluation coefficient of the aluminum ash slag samples at each moment is obtained; Step 4, analyzing the change characteristics of the aluminum separation evaluation coefficient of the aluminum ash slag samples at each moment and the previous moment during the ball milling process, obtaining the evaluation coefficient difference sequence of the aluminum ash slag samples at each moment and the aluminum separation threshold value as the stopping judgment condition of the ball milling of the aluminum ash slag; after stopping the ball milling, sieving all the aluminum ash slag and selecting the aluminum ash slag within the preset particle size range; Step 5, high-temperature smelting the selected aluminum ash slag to obtain aluminum ingots.

2. The aluminum ingot refining process using aluminum ash slag as claimed in claim 1, characterized in that: The cooling atmosphere for natural cooling is argon, and the cooling time is 12 to 24 hours.

3. The aluminum ingot refining process using aluminum ash slag as claimed in claim 1, characterized in that: The specific operation of ball milling is: the mass of aluminum ash slag during ball milling is equal to the mass of steel balls in the ball mill. , the speed of the ball mill is 30~40 rpm.

4. The aluminum ingot refining process using aluminum ash slag as claimed in claim 1, characterized in that: The specific process of obtaining the mass ratio vector of the aluminum ash slag sample at each moment and all particle size sets is as follows: During the ball milling process, a preset mass of aluminum ash slag samples are taken out at each time, and the aluminum ash slag samples at the same time of ball milling are screened into a preset number of portions through a multi-layer linear vibrating screen, and the mass of each portion of aluminum ash slag sample is weighed and arranged in order from large to small according to the average particle size; Obtain the mass ratio of each aluminum ash slag sample as an element of the mass ratio vector of the aluminum ash slag sample at each moment; The mass of each aluminum ash slag sample and the mass of a preset number of subsequent aluminum ash slag samples are set as each particle size set.

5. The aluminum ingot refining process using aluminum ash slag as claimed in claim 1, characterized in that: The process of obtaining the particle size distribution uniformity of the aluminum ash slag sample at each moment is as follows: For the aluminum ash slag samples at each moment, the negative correlation mapping results of the discreteness of the elements in each particle size set are calculated, and the negative correlation mapping results are weighted and summed using the preset weight value of each particle size set to obtain the particle size distribution uniformity of the aluminum ash slag samples at each moment.

6. The aluminum ingot refining process using aluminum ash slag as claimed in claim 1, characterized in that: The formula for obtaining the aluminum separation evaluation coefficient of the aluminum ash slag sample at each time is: ;in, represents the aluminum separation evaluation coefficient of the aluminum ash sample at the i-th moment, represents the difference in particle size distribution uniformity of the aluminum ash slag sample at the i-th moment and the i-1-th moment; exp() represents an exponential function with a natural constant as the base; , Respectively represent the mass ratio vector of the aluminum ash slag sample at the i-th moment and the i-1-th moment; represents the cosine similarity function; is a parameter that is preset to be greater than zero.

7. The aluminum ingot refining process using aluminum ash slag as claimed in claim 1, characterized in that: The evaluation coefficient difference sequence and aluminum separation threshold of the aluminum ash slag samples at each time are obtained as follows: The sequence of aluminum separation evaluation coefficients of aluminum ash slag samples at each moment and a set number of moments before is recorded as an evaluation sequence; the difference sequence of the evaluation sequence at each moment is recorded as the evaluation coefficient difference sequence at each moment; The mean of all elements in the evaluation coefficient difference sequence at each moment is recorded as the aluminum separation threshold.

8. The aluminum ingot refining process using aluminum ash slag as claimed in claim 1, characterized in that: The specific process of the stop determination condition of the ball milling of aluminum ash slag is as follows: If the last element value of the evaluation coefficient difference sequence of the aluminum ash slag sample at the current moment is greater than the aluminum separation threshold at the current moment, the ball milling of the aluminum ash slag is stopped.

9. The aluminum ingot refining process using aluminum ash slag as claimed in claim 1, characterized in that: The particle size of the selected aluminum ash slag is greater than 1.25 mm, and a plasma arc method is used for high-temperature melting. The melting temperature is 700-800°C and the melting time is 1-2 hours.

10. An aluminum ingot refining device using aluminum ash slag, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that: When the processor executes the computer program, the steps of the aluminum ingot refining process using aluminum ash slag as described in any one of claims 1-9 are implemented.

Images