Side shaft furnace structure of single-chamber furnace for UBC secondary aluminum melt purification

Abstract

The invention relates to the field of secondary aluminum industry, in particular to a side shaft furnace structure of a single-chamber furnace for UBC secondary aluminum melt purification, the side shaft furnace is communicated with a main furnace chamber of the single-chamber furnace through two channels to form a closed cycle, and a main runner of the side shaft furnace structure is divided into an inlet area, a feeding area, an inclusion collecting area, an outlet area and a slagging-off area. A numerical calculation simulation experiment verifies that the main runner structure of the side shaft furnace can continuously generate a vortex flow field moving towards the slagging-off area in the inclusion collection area of the main runner during working, and non-metallic inclusions in molten aluminum can be efficiently collected and then accumulated to the slagging-off area to be removed; and the purification efficiency of the regenerated aluminum melt is effectively improved.

Description

Technical Field

[0001] The present invention relates to the field of recycled aluminum industry, and in particular to a side-well furnace structure of a single-chamber furnace for purifying UBC recycled aluminum melt. Background Art

[0002] Recycled aluminum technology usually uses recycled scrap aluminum as raw material, undergoes a series of processing, melting, and composition adjustment, and finally produces cast aluminum ingots or other aluminum alloy products through refining.

[0003] Since recycled scrap aluminum alloy products are used as raw materials, they have a high impurity content. The presence of inclusions will make it difficult to remove hydrogen from the aluminum melt, causing a series of defects such as gas entrapment, shrinkage cavities and porosity, and microcracks in the castings, reducing the material's mechanical properties, corrosion resistance, ductility, surface finish and other properties. Therefore, before casting or deformation processing, the aluminum melt must be subjected to a decontamination and refining process to ensure cleanliness and provide a production basis for downstream high-performance aluminum alloy products.

[0004] The Chinese patent with publication number CN117804221A in the related technology points out that the double-chamber furnace equipped with a circulation pump structure commonly used in the current recycled aluminum production has certain defects: the aluminum liquid in the double-chamber furnace for aluminum smelting is circulated and heated and melted in the two furnaces through a circulation pump, and the aluminum material will produce a large amount of waste slag when it comes into contact with the air during the smelting process due to its large surface area. Especially when the waste aluminum is recycled and smelted, these waste slags are difficult to be effectively cleaned and separated by only using a slag baffle set between the two.

[0005] The rapid development of modern mathematical modeling and computer technology has made it possible to use computer simulation numerical simulation to verify and optimize the aluminum melt purification process. It has the advantages of short cycle, fast speed, low cost, and unlimited process conditions. Numerical simulation of the aluminum melt purification process can verify the optimal aluminum melt purification structure and process efficiently, at low cost and quickly.

[0006] At present, many researchers have conducted qualitative analysis and research on the movement behavior of inclusions in high-temperature molten metal liquids. However, the agglomeration process of non-metallic inclusion particles in high-temperature molten aluminum alloy liquids is still unclear, and more quantitative research is needed. When the particle size of non-metallic inclusion particles is small, the viscous force between the particles generated by the added impurity-removing flux plays a dominant role. Therefore, it is necessary to consider the influence of the viscous force between the particles generated by the added impurity-removing flux on the agglomeration process of non-metallic inclusion particles in high-temperature molten aluminum alloy liquids. Summary of the Invention

[0007] In view of the defects and shortcomings in the above-mentioned technologies, the present application aims to provide a side well furnace structure of a single-chamber furnace for purifying aluminum melt, which can efficiently collect and remove non-metallic inclusions in the aluminum melt and improve the purification efficiency of recycled aluminum melt.

[0008] The side well furnace structure of the single-chamber furnace for purifying UBC recycled aluminum melt provided by the present application adopts the following technical solution: a side well furnace structure of a single-chamber furnace for purifying UBC recycled aluminum melt, wherein the main flow channel of the side well furnace structure is in communication with the main furnace chamber; the bottom surface of the side well furnace structure is at the same level as the bottom surface of the main furnace chamber; the side well furnace structure is in communication with the main furnace chamber of the single-chamber furnace through two connecting channels; the two connecting channels are respectively located at the front end and the end of the bottom of the main flow channel of the side well furnace; and the volume of the side well furnace structure is not greater than 2 / 3 of the volume of the main furnace chamber.

[0009] Further, the main flow channel of the side well furnace structure is divided into a water inlet area, a feeding area, an inclusion collection area, a water outlet area, and a slag removal area.

[0010] Further, a plurality of blocking bodies are arranged at the bottom of the main flow channel of the side well furnace; the main flow channel of the side well furnace is arranged horizontally; one of the blocking bodies is arranged at the front position of the main flow channel of the side well furnace along the fluid direction; and the remaining two blocking bodies are arranged at the middle position of the main flow channel of the side well furnace along the fluid direction.

[0011] Further, the purification efficiency of recycled aluminum melt of the side well furnace structure is verified by numerical calculation simulation experiment; after three-dimensional modeling and mesh division of the side well furnace structure of the single-chamber furnace for purifying UBC recycled aluminum melt, numerical calculation simulation experiment is performed.

[0012] Further, in the numerical calculation simulation experiment, the PBM model in the Eulerian multiphase flow, the standard k-ε model in the turbulent flow model, and the energy model are selected as the solution model; in the numerical calculation simulation experiment, the first phase is liquid aluminum and the second phase is inclusion particle phase; and in the numerical calculation simulation experiment, the basic solution parameters at least include fluid flow rate, fluid viscosity, fluid density, inclusion particle-aluminum liquid surface tension, single inclusion particle diameter, inclusion agglomerate diameter, inclusion agglomerate total volume, and time step.

[0013] Further, the data such as the cloud map of the proportion of inclusion particles floating to the surface layer and the volume fraction of inclusion agglomerates and the liquid flow trajectory map generated after the post-processing of the numerical calculation simulation experiment are analyzed, the simulation conditions are adjusted, and the optimal process parameters of UBC recycled aluminum melt purification are optimized.

[0014] Furthermore, in the numerical calculation simulation experiment, after the aluminum liquid with a certain inclusion particle content enters the side well furnace structure from the water inlet, it is pushed by the fluid and the vortex flow field generated by the obstruction body in the main channel of the side well furnace. The non-metallic inclusions in the aluminum liquid are efficiently collected and accumulated in the slag removal area.

[0015] In summary, the beneficial technical effects of the present application are: 1. Achieve numerical simulation of the agglomeration process of non-metallic inclusion particles in high-temperature molten aluminum alloy liquid, while taking into account the wetting and wrapping effect of the impurity-removing flux on the non-metallic inclusion particles after being added to the aluminum melt. Specifically, when the non-metallic inclusion particles move in the aluminum liquid, the inter-particle force, apparent viscosity, surface tension and density function of the phase interface are redefined according to actual conditions, and the simulation results are more accurate and reliable. 2. The single-chamber furnace side-well furnace structure for purification of UBC recycled aluminum melt is simple in structure and easy to use. It fully utilizes the characteristics of the aluminum liquid in recycled aluminum smelting, further reduces the impurity content of the aluminum melt, and improves the quality of downstream recycled aluminum products. 3. When the single-chamber side-well furnace structure for purifying UBC recycled aluminum melt is in operation, it cooperates with the obstruction body in the main channel to generate a vortex flow field. The impurity-removing flux added to the aluminum liquid is dispersed by the flow field and then wets and wraps the non-metallic inclusions in the aluminum liquid, so that the non-metallic inclusions meet the conditions for agglomeration and floating. In this process, these non-metallic inclusions are also rapidly agglomerated and floated inside the main channel under the action of the vortex flow field, and move toward the slag skimming slope driven by the liquid flow on the upper surface. Finally, the non-metallic inclusions are efficiently gathered and accumulated in the slag skimming area. When the accumulation amount reaches a certain level, the waste slag is removed and cleaned. Such a cycle can realize the continuous cleaning of non-metallic inclusions in the single-chamber side-well furnace for purifying UBC recycled aluminum melt. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the overall structure of an embodiment of the present application;

[0017] Figure 2 is a sectional view of three views of the main channel described in the embodiment of the present application;

[0018] Figure 3 This is a schematic diagram of the structural grid division of an embodiment of the present application;

[0019] Figure 4 This is a graph showing a change trend in the volume percentage of inclusion particles that float to the surface, as produced by the post-processing of the numerical calculation simulation experiment described in the embodiments of the present application;

[0020] Figure 5 It is a cloud diagram of the volume fraction of small-size inclusions along the vertical cross section perpendicular to the flow direction of the molten aluminum, produced by the post-processing of the numerical calculation simulation experiment described in the embodiment of the present application;

[0021] Figure 6 It is a cloud map and liquid flow trace diagram of the volume fraction of inclusion agglomerates along the vertical longitudinal section of the aluminum liquid flow direction produced by the numerical calculation simulation experiment post-processing described in the embodiment of the present application;

[0022] Figure 7 It is a cloud map and a liquid flow trace line map of the volume fraction of inclusion agglomerates on the upper surface of the side shaft furnace structure produced by the post-processing of the numerical calculation simulation experiment described in the embodiment of the present application;

[0023] Explanation of the reference numerals: 1. Flow direction; 2. Third barrier; 3. First barrier; 4. Slag skimming slope; 5. Outlet; 6. Second barrier; 7. Main channel; 8. Inlet. DETAILED DESCRIPTION

[0024] The following will clearly and completely describe the technical solution of this application in conjunction with the accompanying drawings. Obviously, the embodiments described are only part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of this application.

[0025] The embodiment of the present application discloses a side well furnace structure of a single chamber furnace for purification of UBC recycled aluminum melt. Figure 1 and Figure 2 The bottom surface of the side well furnace structure is at the same horizontal plane as the bottom surface of the main furnace chamber; the side well furnace structure is connected with the main furnace chamber of the single-chamber furnace through two connecting channels 5 and 8; the two connecting channels 5 and 8 are respectively located at the front end and the end of the bottom of the side well furnace main channel 7; a plurality of blocking bodies 2, 3, and 6 are respectively arranged at the bottom of the side well furnace main channel 7; the side well furnace main channel 7 is arranged horizontally; the blocking body 3 is arranged at the front position of the side well furnace main channel 7 along the fluid direction 1; the remaining two blocking bodies 2 and 6 are arranged at the middle position of the side well furnace main channel 7 along the fluid direction 1; a slag skimming slope 4 is arranged in the side well furnace main channel 7, and the specific position is at the end position of the side well furnace main channel 7 along the fluid direction 1.

[0026] Numerical calculation simulation experiments were used to verify the purification efficiency of the recycled aluminum melt of the structure. The specific steps are: 1. Construct a mathematical function of custom physical parameters; 2. Use 3D modeling software to construct a geometric model of the aluminum liquid flow area of ​​the side shaft furnace of the UBC recycled aluminum smelting furnace; 3. Finite element meshing of the 3D geometric model; 4. Mesh unit quality inspection; 5. Import the mesh file into the simulation software and set the dimensional unit; 6. Import the user-defined function; 7. Select a numerical model to simulate the agglomeration process of non-metallic slag in aluminum melt; 8. Set the material properties of each part; 9. Set the conditions of each internal calculation domain; 10. Assign materials; 11. Set boundary conditions, including momentum boundary and thermal boundary; 12. Select the solution method; 13. Set the time step and number of steps; 14. Initialize the boundary and start the calculation; 15. Post-processing and analysis.

[0027] Specifically, refer to Figure 3 The three-dimensional geometric model of the side shaft furnace of the UBC secondary aluminum smelting furnace is divided into 2376920 tetrahedral grid units, and the average grid quality of all units is 0.8386; the solution model uses the PBM model in the Euler multiphase flow, the standard k-ε model in the turbulence model, and the energy model; the material phase is set as liquid aluminum in the first phase and inclusion particle phase in the second phase. The physical properties of these materials are set using the mathematical functions of user-defined physical property parameters; refer to Figure 1 The boundary condition of inlet 5 is set as velocity boundary. Liquid aluminum with a certain content of small-size inclusion particles flows into the side well furnace from the inlet at a certain initial velocity. The boundary condition of outlet 8 is set as pressure boundary. The initial gauge pressure is 0 Pa. The upper surface is set as a non-viscous boundary with a fluid shear force of 0. Other boundaries are set as non-slip rigid walls. The basic solution parameters of this numerical calculation simulation experiment include at least: fluid flow rate, fluid viscosity, fluid density, inclusion particle-aluminum liquid surface tension, single inclusion particle diameter, inclusion agglomerate diameter, total volume of inclusion agglomerates and time step.

[0028] The data such as the proportion of inclusion particles floating to the surface, the volume fraction cloud map of inclusion agglomerates at key positions and the liquid flow trace diagram produced by the post-processing of the numerical calculation simulation experiment were analyzed.

[0029] After the inclusions in the aluminum liquid are gathered on the upper surface of the side furnace by the action of the impurity removal flux, they are scraped off with a slag shovel to reduce the impurity content in the aluminum liquid. Therefore, in the simulation experiment, the proportion of inclusion particles floating to the surface is used to characterize the purification efficiency of the recycled aluminum melt of the side well furnace structure. Figure 4The simulation experimental data show that as the vortex flow field acts for an increasing time, the proportion of inclusion particles floating to the surface increases accordingly, and gradually stabilizes to a value after a certain period of time. Compared with the conventional side-well furnace structure without adding a barrier in the main channel, the improved side-well furnace structure adopted in this application has a higher proportion of inclusion particles floating to the surface in the simulation experiment by about 15%, that is, the improved side-well furnace structure has a higher melt purification efficiency.

[0030] Reference Figure 5 and Figure 6 , regarding the movement and agglomeration of inclusion particles inside the main channel: after the small-sized inclusion particles enter the main channel of the side-well furnace from the water inlet, they are gradually dispersed to various parts of the side-well furnace body with the movement of the fluid. At the same time, they are agglomerated into larger particle agglomerates near the upper surface under the action of the vortex flow field, and the overall liquid flow near the surface is from front to back, which is conducive to the accumulation of slag particle agglomerates at the rear end of the side-well furnace; in addition, there is a vertical liquid flow in the middle section of the main channel with a turbulent flow trend. This phenomenon is conducive to the particle agglomerates near the surface to re-enter the melt and absorb the small-sized inclusions inside.

[0031] Reference Figure 7 The agglomeration and accumulation of inclusion particle agglomerates on the surface: a stable vortex will be generated at the front end of the upper surface, and the upwelling liquid flow on the outer side of the front end will be divided into two streams, flowing forward and backward respectively. The former will meet the latter after forming a vortex around the front end. If the kinetic energy of these two liquid streams is equivalent, they will converge in the middle to form a liquid flow that flows directly from the front vortex to the rear end. The particles that would have been detained at the front vortex are sent to the rear end through this liquid flow, so they will not agglomerate and accumulate at the front end.

[0032] The implementation principle of the side-well furnace structure of a single-chamber furnace for purifying UBC recycled aluminum melt in an embodiment of the present application is as follows: the main channel structure of the side-well furnace can continuously generate a vortex flow field moving toward the slag skimming area in the inclusion collection area of ​​the main channel when working. The impurity-removing flux added to the molten aluminum is dispersed by the flow field and then wets and wraps the non-metallic inclusions in the molten aluminum, so that the non-metallic inclusions meet the conditions for agglomeration and floating. In this process, these non-metallic inclusions are also rapidly agglomerated and floated inside the main channel under the action of the vortex flow field, and move toward the slag skimming slope driven by the liquid flow on the upper surface. Finally, the non-metallic inclusions are efficiently gathered and accumulated in the slag skimming area. When the accumulation amount reaches a certain level, the waste slag is skimmed and cleaned. Such a cycle can achieve continuous cleaning of non-metallic inclusions in the side-well furnace of the single-chamber furnace for purifying UBC recycled aluminum melt.

[0033] The above are preferred embodiments of the present application, and are not intended to limit the scope of protection of the present application. Therefore, any equivalent changes made based on the structure, shape, and principle of the present application should be included in the scope of protection of the present application.

Claims

1. A side-well furnace structure with a single-chamber furnace for purification of UBC recycled aluminum melt, characterized by: The main channel (7) is interconnected with the main furnace chamber; the bottom surface of the side well furnace structure and the bottom surface of the main furnace chamber are at the same horizontal plane; the side well furnace structure is connected with the main furnace chamber of the single-chamber furnace through two connecting channels (5, 8); the two connecting channels (5, 8) are respectively located at the front end and the end of the bottom of the main channel (7) of the side well furnace; the volume of the side well furnace structure is not greater than 2 / 3 of the volume of the main furnace chamber.

2. The side-well furnace structure of a single-chamber furnace for purifying UBC recycled aluminum melt according to claim 1 is characterized in that: The main channel is divided into an inlet area, a feeding area, an inclusion collection area, an outlet area and a slag removal area.

3. The side well furnace structure of a single-chamber furnace for purifying UBC recycled aluminum melt according to claim 1 is characterized in that: A plurality of blocking bodies (2, 3, 6) are respectively arranged at the bottom of the main channel (7) of the side well furnace; the main channel (7) of the side well furnace is arranged horizontally; the blocking body (3) is arranged at the front position of the main channel (7) of the side well furnace along the fluid direction (1); and the remaining two blocking bodies (2, 6) are arranged at the middle position of the main channel (7) of the side well furnace along the fluid direction (1).

4. The side-well furnace structure of a single-chamber furnace for purifying UBC recycled aluminum melt according to claim 1 is characterized in that: A slag removal slope (4) is provided in the main channel (7) of the side shaft furnace; the slag removal slope (4) is provided at the end position of the main channel (7) of the side shaft furnace along the fluid direction (1).

5. A side-well furnace structure of a single-chamber furnace for purifying UBC recycled aluminum melt, and a numerical calculation simulation experiment are used to verify the purification efficiency of the recycled aluminum melt of the structure. After three-dimensional modeling and meshing of the side-well furnace structure of a single-chamber furnace for purifying UBC recycled aluminum melt according to any one of claims 1 to 4, numerical calculation simulation experiments are carried out.

6. According to the numerical calculation simulation experiment of claim 5, the solution model selects the PBM model in Euler multiphase flow, the standard k-ε model in turbulence model, and the energy model; in the numerical calculation simulation experiment, the material phase setting is that the first phase is liquid aluminum and the second phase is the inclusion particle phase; in the numerical calculation simulation experiment, the basic solution parameters include at least: Fluid flow rate, fluid viscosity, fluid density, inclusion particle-aluminum liquid surface tension, single inclusion particle diameter, inclusion agglomerate diameter, total volume of inclusion agglomerates, and time step.

7. According to the numerical calculation simulation experiment described in claim 5, the data such as the proportion of inclusion particles floating to the surface, the cloud map of the volume fraction of inclusion agglomerates in key positions, and the liquid flow trace diagram produced by the post-processing output are analyzed to adjust the simulation conditions and optimize the optimal process parameters for the purification of UBC recycled aluminum melt.

8. According to the numerical calculation simulation experiment described in claim 5, after the aluminum liquid with a certain inclusion particle content enters the side well furnace structure according to any one of claims 1 to 6 from the water inlet (8), it is pushed by the fluid and the vortex flow field generated by the blocking body (2, 3, 6) in the main channel (7) of the side well furnace. The non-metallic inclusions in the aluminum liquid are efficiently collected and accumulated in the slag removal area.

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