Method for preparing high-grade aluminum by separating and recycling low-quality liquid aluminum through segregation method
Through the multi-step processing of the dumping device, the balanced distribution characteristics of Si and Fe elements are used to solve the problem of impurities in low-quality liquid aluminum, and the high-quality aluminum recycling with low cost and low energy consumption is achieved, which improves economic benefits and reduces energy consumption. .
Patent Information
- Application Number
- CN202411274563.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-12
- Publication Date
- 2024-12-13
AI Technical Summary
The low-quality liquid aluminum produced by the existing segregation method when producing high-quality aluminum is produced due to the high impurity content, which leads to poor electrical properties, ductility, corrosion resistance and light reflectivity, which cannot be used in high-tech fields, and the impurity removal process consumes a lot of energy. , high cost and poor economic benefits.
Through the pouring device, the equilibrium distribution coefficient of Si element and Fe element is less than 1, so that it can migrate and enrich to the liquid phase, gradually improve the purity of aluminum liquid, and realize the recovery of advanced aluminum. The specific steps include the following: Pour one to pour out scrap aluminum enriched with Si and Fe elements, and the second pour to obtain high-grade aluminum, with an aluminum content reaching 99.90%-99.92%.
The conversion of low-quality liquid aluminum into high-quality aluminum at low cost and low energy consumption is achieved, avoiding additional energy consumption and improving economic benefits. A single separation and recovery of 1 ton of low-quality liquid aluminum can generate about 2,000 yuan of economic benefits.
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Figure CN119120909A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of refined aluminum recovery, and in particular to a method for preparing high-grade aluminum by separating and recovering low-quality liquid aluminum using a segregation method. Background Art
[0002] High-grade aluminum is refined aluminum with a purity of more than 99.90%. The higher the purity of high-grade aluminum, the better its conductivity, ductility, corrosion resistance, plasticity and reflectivity, while the lower its magnetic conductivity, tensile strength and yield strength. The grain size of high-grade aluminum is larger than that of ordinary aluminum ingots, which enhances its conductivity, ductility, reflectivity and corrosion resistance. At present, the main uses of high-grade aluminum (purity 99.90-99.995%) are in the fields of high technology and scientific research, such as making high-voltage capacitor aluminum foil, electronic aluminum foil, electronic guide wire, cathode vacuum spraying, integrated circuit bonding wire, storage hard disk, etc. It can also be used in aerospace and special-purpose high-purity aluminum-lithium alloy, aluminum-scandium alloy and other fields.
[0003] At present, the production methods of high-grade aluminum mainly include segregation method, three-layer liquid electrolysis method, zone smelting method, distributed crystallization method and organic liquid purification method, among which the segregation method and three-layer liquid electrolysis method are the main production methods. Due to the characteristics of large output, low energy consumption and low cost, the segregation method is more widely used than the three-layer liquid electrolysis method and is the main method for producing high-grade aluminum.
[0004] However, in the process of producing refined aluminum ingots using the segregation method, a portion of low-quality liquid aluminum will be produced, and the aluminum content of low-quality liquid aluminum is roughly 99.2% to 99.6%. Since low-quality liquid aluminum contains more impurities, its electrical properties, ductility, corrosion resistance, plasticity and reflectivity are poor, resulting in this part of waste material that can only be used to produce low-end aluminum alloy products and cannot be used in high-tech fields and scientific research fields. However, if the low-quality liquid aluminum is removed, a large amount of natural gas, electricity and other energy sources will be consumed, resulting in increased costs and poor economic benefits.
[0005] Therefore, how to use low-quality liquid aluminum to recover high-grade aluminum in a low-cost and low-energy manner has become a technical problem that needs to be urgently solved in this field. Summary of the invention
[0006] The purpose of the present invention is to provide a method for preparing high-grade aluminum by separating and recovering low-quality liquid aluminum using a segregation method. The method provided by the present invention can obtain high-grade aluminum using low-quality liquid aluminum without the need for additional consumption of natural gas, electricity and other energy sources, with low cost and good economic benefits.
[0007] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:
[0008] The present invention provides a method for preparing high-grade aluminum by separating and recovering low-quality liquid aluminum using a segregation method, comprising the following steps:
[0009] (1) placing a container containing low-quality liquid aluminum into a dumping device for a first dumping to obtain high-quality liquid aluminum and scrap aluminum enriched with Si and Fe elements; the first dumping angle is 92° to 120°, and the first dumping time is 30 to 60 seconds;
[0010] (2) Pour the high-grade liquid aluminum obtained in step (1) for a second time to obtain high-grade aluminum.
[0011] Preferably, the temperature of the low-quality liquid aluminum in step (1) is 660-700°C.
[0012] Preferably, the dumping device in step (1) comprises a crucible fixture, a crucible sleeve, a rotating shaft, a horizontal fixed shaft, a lifting cylinder and a fixed bracket.
[0013] Preferably, a crucible clamp is provided on the top of the crucible sleeve in the dumping device, the crucible sleeve is located inside the lifting cylinder and is connected to the inside of the cylinder through a fixed bracket, a rotating shaft is provided at an opposite position to the top of the lifting cylinder, and a horizontal fixed shaft is provided on the top of the lifting cylinder.
[0014] Preferably, the angle of the first pouring in step (1) is 95° to 115°, and the time of the first pouring is 40 to 50 seconds.
[0015] Preferably, after the first dumping in step (1) is completed, the dumping device is tilted back to the original angle.
[0016] Preferably, the angle of the second pouring in step (2) is 92° to 120°, and the time of the second pouring is 30 to 60 minutes.
[0017] Preferably, the angle of the second pouring in step (2) is 95° to 115°, and the time of the second pouring is 40 to 50 minutes.
[0018] The present invention provides high-grade aluminum obtained by the method described in the above technical solution.
[0019] Preferably, the aluminum content in the high-grade aluminum is 99.90-99.92 wt.%.
[0020] The present invention provides a method for preparing high-grade aluminum by separating and recovering low-quality liquid aluminum using a segregation method, comprising the following steps: (1) placing a container containing low-quality liquid aluminum into a pouring device for a first pouring to obtain high-grade liquid aluminum and waste aluminum enriched with Si and Fe elements; the angle of the first pouring is 92° to 120°, and the time of the first pouring is 30 to 60 seconds; (2) pouring the high-grade liquid aluminum obtained in the step (1) for a second time to obtain high-grade aluminum. The present invention uses the segregation phenomenon generated by the melt during the solidification process to purify the low-quality liquid aluminum based on the principle that the equilibrium distribution coefficients of different elements in the aluminum melt are different. The low-quality liquid aluminum gradually solidifies during the pouring process. In this process, since the equilibrium distribution coefficients of Si and Fe elements are less than 1, Si and Fe elements migrate to the liquid phase for enrichment, and the concentrations of Si and Fe elements increase successively from the solid phase to the solid-liquid interface and then to the liquid phase, so that the liquid aluminum enriched with Si and Fe elements can be poured out during the pouring process, thereby increasing the content of aluminum elements in the aluminum melt and further realizing the recovery of high-grade aluminum. The present invention adopts a multi-step pouring method, pours out the top layer of liquid waste aluminum enriched with Si and Fe elements in the first pouring, obtains liquid waste aluminum enriched with Si and Fe elements, and then performs a second pouring to pour out all the remaining high-grade liquid aluminum to obtain high-grade aluminum with an aluminum content of 99.90% to 99.92%, thereby realizing the graded separation of segregated waste aluminum. The process flow of the method provided by the present invention is simple to operate and convenient to implement, and no additional consumption of natural gas, electricity and other energy sources is required, and it has good economic benefits. The results of the embodiment show that the separation and recovery method provided by the present invention uses the segregation method to separate low-quality liquid aluminum with an aluminum content of 99.2 to 99.6wt.%, and can obtain high-grade aluminum with an aluminum content of 99.90 to 99.92wt%. In the separation and recovery process, no additional consumption of natural gas, electricity and other energy sources is required. By analyzing the price of high-grade aluminum in the current market, it is found that each graded separation and recovery of 1 ton of low-quality liquid aluminum generates an economic benefit of about 2,000 yuan, which has important practical value. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Figure 1 A schematic diagram of the structure of the dumping device provided by the present invention;
[0022] Figure 1 Among them, 1 is a crucible fixture, 2 is a crucible sleeve, 3 is a rotating shaft, 4 is the ground, 5 is a horizontal fixed shaft, 6 is a rotating shaft, 7 is a lifting cylinder, and 8 is a fixed bracket;
[0023] Figure 2 Schematic diagram of the solid-liquid distribution of aluminum in the crucible before the first pouring. DETAILED DESCRIPTION
[0024] The present invention provides a method for preparing high-grade aluminum by separating and recovering low-quality liquid aluminum using a segregation method, comprising the following steps:
[0025] (1) placing a container containing low-quality liquid aluminum into a dumping device for a first dumping to obtain high-quality liquid aluminum and scrap aluminum enriched with Si and Fe elements; the first dumping angle is 92° to 120°, and the first dumping time is 30 to 60 seconds;
[0026] (2) Pour the high-grade liquid aluminum obtained in step (1) for a second time to obtain high-grade aluminum.
[0027] The invention puts a container containing low-quality liquid aluminum into a pouring device for the first pouring to obtain high-quality liquid aluminum and waste aluminum enriched with Si elements and Fe elements.
[0028] In the present invention, the low-quality liquid aluminum is preferably the low-quality liquid aluminum produced when high-quality aluminum is prepared by the segregation method. In the present invention, the aluminum content in the low-quality liquid aluminum is preferably 99.2-99.6wt.%; the impurities in the low-quality liquid aluminum preferably include Si and Fe elements. The present invention recovers high-quality aluminum by using the above-mentioned low-quality liquid aluminum. Since the main impurity elements in the low-quality liquid aluminum are Si and Fe, the content of Si and Fe directly affects the purity of aluminum. By removing part of the higher concentration of Si and Fe in the segregated waste aluminum, high-quality aluminum ingots can be obtained.
[0029] In the present invention, the temperature of the low-quality liquid aluminum is preferably 660-700° C., more preferably 670-690° C., and further preferably 680° C. The present invention controls the temperature of the low-quality liquid aluminum to be close to the melting point of aluminum, so that the low-quality liquid aluminum can be gradually solidified during the pouring process. In this process, the Si element and the Fe element are migrated to the liquid phase for enrichment by utilizing the characteristics that the equilibrium distribution coefficient of the Si element and the Fe element is less than 1, and the concentrations of the Si element and the Fe element increase successively from the solid phase to the solid-liquid interface and then to the liquid phase, thereby facilitating the pouring process to pour out the liquid aluminum enriched with the Si element and the Fe element.
[0030] In the present invention, the container is preferably a crucible. The present invention has no particular limitation on the specific material of the crucible, and a crucible known to those skilled in the art that can hold molten aluminum and does not react with it can be used. The present invention has no particular limitation on the size of the crucible, and those skilled in the art can determine it according to the production process or use a commercially available crucible known to those skilled in the art for industrial production.
[0031] The present invention has no particular limitation on the amount of low-quality liquid aluminum added, which can be determined based on the technical knowledge of those skilled in the art, as long as the low-quality liquid aluminum is kept 10 to 30 cm away from the edge of the crucible.
[0032] The present invention has no special limitation on the specific structure of the dumping device, as long as the dumping angle and time can be controlled.
[0033] like Figure 1 As shown, in one embodiment of the present invention, the dumping device includes a crucible fixture, a crucible sleeve, a rotating shaft, a horizontal fixed shaft, a lifting cylinder and a fixed bracket.
[0034] In the present invention, a crucible clamp is provided at the top of the crucible sleeve in the dumping device, the crucible sleeve is located inside the lifting cylinder, and is connected to the inside of the cylinder through a fixed bracket, a rotating shaft is provided at the opposite position of the top of the lifting cylinder, and a horizontal fixed shaft is provided at the top of the lifting cylinder. The present invention controls the structure of the dumping device. During the dumping process, the lifting cylinder of the dumping device starts to rise, and the rotating shaft of the dumping device rotates around the horizontal fixed shaft. When the dumping angle of the aluminum crucible meets the requirements, the lifting cylinder stops working and dumps the liquid aluminum. The dumping device provided by the present invention has a simple structure and good controllability, and can effectively control the dumping angle and dumping time, so as to facilitate better improvement of the quality of the liquid aluminum.
[0035] The schematic diagram of the solid-liquid distribution of aluminum in the crucible before the first pouring is as follows Figure 2 As shown. Figure 2 It can be seen that since the temperature of the low-quality liquid aluminum is near the melting point of aluminum, the low-quality liquid aluminum presents a solid phase and a liquid phase in the container. During the pouring process, the upper liquid phase is mainly poured out.
[0036] In the present invention, the angle of the first pouring is 92° to 120°, preferably 95° to 115°, more preferably 100° to 110°, and further preferably 105°; the time of the first pouring is 30 to 60s, preferably 40 to 50s. In the present invention, the equilibrium distribution coefficient refers to the ratio of the concentrations of the solute in the two phases when the solid-liquid two-phase system reaches an equilibrium state. Since the equilibrium distribution coefficient of the Si element in aluminum is about 0.027, and the equilibrium distribution coefficient of the Fe element in aluminum is about 0.024, both of which are less than 1, the upper layer of the solid-liquid interface has a higher enrichment of Si and Fe elements in the liquid aluminum, and the higher the element content. Therefore, by pouring and controlling the pouring angle and time, the uppermost layer of liquid aluminum enriched in Si and Fe elements can be separated from the lower liquid aluminum with a high aluminum content, and aluminum liquids with different aluminum contents will be obtained.
[0037] After the first pouring is completed, the present invention preferably tilts the pouring device back to the original angle. The present invention can avoid the continued pouring of aluminum liquid by tilting the pouring device back to the original angle, thereby avoiding the waste of aluminum liquid and improving the recovery rate of high-grade aluminum.
[0038] After obtaining high-grade liquid aluminum and waste aluminum enriched with Si and Fe elements, the present invention dumps the high-grade liquid aluminum for a second time to obtain high-grade aluminum.
[0039] In the present invention, the angle of the second pouring is preferably 92° to 120°, more preferably 95° to 115°, and further preferably 100°, 105° or 110°; the time of the second pouring is preferably 30 to 60 minutes, and more preferably 40 to 50 minutes. The present invention can pour out all the molten aluminum by controlling the angle and time of the second pouring, thereby leaving solid phase high-grade aluminum with a higher aluminum content.
[0040] In the present invention, the high-grade aluminum includes the aluminum ingot solidified after the second pouring and the solid phase aluminum formed in the container due to cooling during the first pouring and the second pouring.
[0041] The present invention is based on the principle that different elements have different equilibrium distribution coefficients in molten aluminum, and utilizes the segregation phenomenon generated in the solidification process of the melt to purify. Low-quality liquid aluminum gradually solidifies during the pouring process. In this process, the characteristics that the equilibrium distribution coefficients of Si and Fe elements are less than 1 are utilized to make Si and Fe elements migrate to the liquid phase for enrichment, and the concentrations of Si and Fe elements increase successively from the solid phase to the solid-liquid interface and then to the liquid phase, so that the liquid aluminum enriched with Si and Fe elements can be poured out during the pouring process, thereby increasing the content of aluminum in the aluminum liquid and further realizing the recovery of high-grade aluminum.
[0042] The present invention adopts a multi-step pouring method, in which the top layer of liquid scrap aluminum enriched with Si and Fe elements is poured out in the first pouring to obtain liquid scrap aluminum enriched with Si and Fe elements, and then a second pouring is performed to pour out all the remaining high-grade liquid aluminum to obtain high-grade aluminum with an aluminum content of 99.90% to 99.92%, thereby realizing the graded separation of segregated scrap aluminum.
[0043] The method provided by the present invention has simple operation and convenient implementation. It can upgrade part of the segregation waste with an aluminum content of 99.2% to 99.6% to high-grade aluminum with an aluminum content of 99.90% to 99.92% without consuming additional energy such as natural gas and electricity. High-grade aluminum can produce more sophisticated aluminum alloy products, improve economic benefits and reduce waste of aluminum resources. Each ton of graded separation and recovery will generate an economic benefit of about 2,000 yuan.
[0044] The present invention also provides high-grade aluminum obtained by the method described in the above technical solution. In the present invention, the aluminum content in the high-grade aluminum is preferably 99.90-99.92 wt.%, and can be used to produce more sophisticated aluminum alloy products.
[0045] 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.
[0046] Example 1
[0047] A method for preparing high-grade aluminum by separating and recovering low-quality liquid aluminum using a segregation method, comprising the following steps:
[0048] (1) Place the crucible containing low-quality liquid aluminum into Figure 1 The first pouring is performed in the pouring device shown, and then the pouring device is tilted back to the original angle to obtain high-grade liquid aluminum and waste aluminum enriched with Si and Fe elements; the low-quality liquid aluminum is a low-quality liquid aluminum with an aluminum content of 99.4wt.% produced when high-grade aluminum is prepared by segregation method, and the main impurity elements are Si and Fe elements; the temperature of the low-quality liquid aluminum is 680°C; the angle of the first pouring is 95°, and the time of the first pouring is 45s;
[0049] (2) pouring the high-grade liquid aluminum obtained in step (1) for a second time to obtain high-grade aluminum; the angle of the second pouring is 120°, and the time of the second pouring is 40 minutes.
[0050] By analyzing the composition of the high-grade aluminum obtained in Example 1, the aluminum content in the high-grade aluminum is 99.92wt%, which meets the requirements of high-grade aluminum and can be used for high-precision aluminum alloy products.
[0051] Example 2
[0052] A method for preparing high-grade aluminum by separating and recovering low-quality liquid aluminum using a segregation method, comprising the following steps:
[0053] (1) Place the crucible containing low-quality liquid aluminum into Figure 1 The first pouring is performed in the pouring device shown, and then the pouring device is tilted back to the original angle to obtain high-grade liquid aluminum and waste aluminum enriched with Si and Fe elements; the low-quality liquid aluminum is a low-quality liquid aluminum with an aluminum content of 99.2wt.% produced when high-grade aluminum is prepared by segregation method, and the main impurity elements are Si and Fe elements; the temperature of the low-quality liquid aluminum is 690°C; the angle of the first pouring is 100°, and the time of the first pouring is 45s;
[0054] (2) pouring the high-grade liquid aluminum obtained in step (1) for a second time to obtain high-grade aluminum; the angle of the second pouring is 120°, and the time of the second pouring is 45 minutes.
[0055] By analyzing the composition of the high-grade aluminum obtained in Example 2, the aluminum content in the high-grade aluminum is 99.91wt%, which meets the requirements of high-grade aluminum and can be used for high-precision aluminum alloy products.
[0056] Example 3
[0057] A method for preparing high-grade aluminum by separating and recovering low-quality liquid aluminum using a segregation method, comprising the following steps:
[0058] (1) Place the crucible containing low-quality liquid aluminum into Figure 1 The first pouring is performed in the pouring device shown, and then the pouring device is tilted back to the original angle to obtain high-quality liquid aluminum and waste aluminum enriched with Si and Fe elements; the low-quality liquid aluminum is a low-quality liquid aluminum with an aluminum content of 99.6wt.% produced when high-quality aluminum is prepared by segregation method, and the main impurity elements are Si and Fe elements; the temperature of the low-quality liquid aluminum is 680°C; the angle of the first pouring is 100°, and the time of the first pouring is 50s;
[0059] (2) The high-grade liquid aluminum obtained in step (1) is poured for a second time to obtain high-grade aluminum; the angle of the second pouring is 120°, and the time of the second pouring is 55 minutes.
[0060] By analyzing the composition of the high-grade aluminum obtained in Example 3, the aluminum content in the high-grade aluminum is 99.92wt%, which meets the requirements of high-grade aluminum and can be used for high-precision aluminum alloy products.
[0061] As can be seen from Examples 1 to 3, the separation and recovery method provided by the present invention uses a segregation method to separate low-quality liquid aluminum with an aluminum content of 99.2 to 99.6 wt.%, and can obtain high-quality aluminum with an aluminum content of 99.90 to 99.92 wt.%. In the separation and recovery process, no additional energy such as natural gas and electricity is consumed. By analyzing the price of high-quality aluminum in the current market, it is found that each graded separation and recovery of 1 ton of low-quality liquid aluminum generates an economic benefit of about 2,000 yuan, which has important practical value.
[0062] 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 high-grade aluminum by separating and recovering low-quality liquid aluminum using a segregation method, comprising the following steps: (1) placing a container containing low-quality liquid aluminum into a dumping device for a first dumping to obtain high-quality liquid aluminum and scrap aluminum enriched with Si and Fe elements; the first dumping angle is 92° to 120°, and the first dumping time is 30 to 60 seconds; (2) Pour the high-grade liquid aluminum obtained in step (1) for a second time to obtain high-grade aluminum.
2. The method according to claim 1, characterized in that In the step (1), the temperature of the low-quality liquid aluminum is 660-700°C.
3. The method according to claim 1, characterized in that The dumping device in step (1) comprises a crucible fixture, a crucible sleeve, a rotating shaft, a horizontal fixed shaft, a lifting cylinder and a fixed bracket.
4. The method according to claim 3, characterized in that A crucible fixture is arranged on the top of the crucible sleeve in the dumping device. The crucible sleeve is located inside the lifting cylinder and is connected to the inside of the cylinder through a fixed bracket. A rotating shaft is arranged at an opposite position to the top of the lifting cylinder, and a horizontal fixed shaft is arranged on the top of the lifting cylinder.
5. The method according to claim 1, characterized in that The angle of the first pouring in the step (1) is 95° to 115°, and the time of the first pouring is 40 to 50 seconds.
6. The method according to claim 1, characterized in that After the first dumping in step (1) is completed, the dumping device is tilted back to the original angle.
7. The method according to claim 1, characterized in that The angle of the second pouring in the step (2) is 92° to 120°, and the time of the second pouring is 30 to 60 minutes.
8. The method according to claim 1 or 7, characterized in that: The angle of the second pouring in the step (2) is 95° to 115°, and the time of the second pouring is 40 to 50 minutes.
9. High-grade aluminum obtained by the method according to any one of claims 1 to 9.
10. The high-grade aluminum according to claim 9, characterized in that The content of aluminum in the high-grade aluminum is 99.90-99.92 wt.%.