A method and system for rapid separation of steel-aluminum anode explosive welding blocks

Abstract

The application relates to the technical field of separation and recovery of composite materials, in particular to a rapid separation method and system of steel-aluminum anode explosion-welded blocks. The method uniformly heats the steel-aluminum anode explosion-welded blocks to 500-600 DEG C, the temperature rising time is not more than 25 min, and the temperature holding time is not less than 20 min; then the heated steel-aluminum anode explosion-welded blocks are subjected to at least three-stage gradient rapid cooling, the cooling time of each stage is not more than 5 s, and finally the temperature is cooled to not higher than 30 DEG C; the cooled material is separated and recovered by using magnetic separation to separate and recover steel and aluminum, and a rapid separation system of steel-aluminum anode explosion-welded blocks is established by using the method, which comprises a scrapped weld block storage area, a material car conveying system, a heating furnace, a sectional cooling area and a magnetic separation machine. The method and the system do not utilize external force, realize automatic separation and classification of steel-aluminum by means of the surface tension difference of steel and aluminum, have the advantages of high separation speed, high efficiency, high recovery rate and no influence of the components of regenerated materials on each other.

Description

Technical Field

[0001] This invention relates to the field of composite material separation and recycling technology, specifically to a rapid separation method and system for steel-aluminum anode explosive weld blocks. Background Technology

[0002] In the production of electrolytic aluminum, the anode section of the electrolytic cell includes: aluminum guide rods, anode steel claws, explosive weld blocks, and anode carbon blocks. As the anode carbon blocks are consumed, the aluminum guide rods and steel claws, subjected to prolonged high temperatures of approximately 960℃, undergo deformation, weld cracking, and breakage. It is necessary to repair, weld, and straighten the steel claws of the original anode assembly, and to separate the scrapped steel-aluminum explosive weld blocks for reuse. Traditional processing methods generally include the following:

[0003] 1. Physically forcibly removing or sawing explosive weld blocks to separate and recycle steel and aluminum is employed. For example, Chinese patent CN113231681A discloses a tool and method for separating explosive weld blocks from aluminum electrolytic anode guide rods. However, the saw blade or tool is prone to skew, and sawing aluminum-aluminum welds and steel-aluminum joint surfaces can easily cause the saw blade or tool to get stuck. Furthermore, a significant amount of aluminum remains on the waste explosive weld blocks at the steel-aluminum joint surface. It can be seen that this method involves a large workload for personnel, is slow, has a low recovery rate, poses significant safety hazards during operation, and cannot achieve batch separation, classification, and secondary recycling.

[0004] 2. While the aluminum layer can be melted and recycled by utilizing the different melting point ranges of steel and aluminum, the iron content in the molten aluminum cannot be precisely controlled, which cannot meet the needs of high-end aluminum production. Moreover, the aluminum adhering to the steel of the waste exploded weld blocks cannot be cleanly recycled.

[0005] 3. The pressure-release separation method is adopted. The guide rod is fixed by tooling, and the pressure is applied to the explosive weld block by a hydraulic press to break the aluminum-aluminum weld. This method is more efficient than the previous two methods, but it is more dangerous in operation. There will also be aluminum plates on the waste explosive weld block, which is also not conducive to material recycling.

[0006] The drawbacks of these processing methods include high workload, slow efficiency, low recycling rate, and significant safety hazards during operation, making it impossible to achieve batch separation, classification, and secondary recycling.

[0007] To address the above shortcomings, it is necessary to develop a method and system for separating steel and aluminum anode explosive weld blocks that is safe to operate, has a high recovery rate, high processing efficiency, and can achieve batch processing. Summary of the Invention

[0008] To address the problems of existing technologies, this invention proposes a rapid separation method for steel-aluminum anode explosive weld blocks, comprising the following steps:

[0009] S1: Heat the steel-aluminum anode explosion welding block to 500-600℃, with a heating time not exceeding 25 minutes and a holding time of not less than 20 minutes;

[0010] S2: The heated steel-aluminum anode explosive weld block is subjected to at least three levels of rapid cooling, with each level of cooling time not exceeding 5 seconds. The temperature after the first level of rapid cooling is not higher than 150°C, and the final temperature is not higher than 40°C.

[0011] S3: The cooled material is separated and recycled using magnetic separation to separate steel and aluminum.

[0012] Furthermore, the heating process in step S1 is a uniform temperature rise process.

[0013] Furthermore, the heating time in step S1 is 10-20 minutes, and the holding time is 20-25 minutes.

[0014] Furthermore, the rapid cooling in step S2 is a three-stage gradient rapid cooling process. The first-stage rapid cooling process reduces the temperature of the steel-aluminum anode explosive weld block to below 100°C within 5 seconds, the second-stage rapid cooling process reduces the temperature of the steel-aluminum anode explosive weld block to below 60°C within 5 seconds, and the third-stage rapid cooling process reduces the temperature of the steel-aluminum anode explosive weld block to below 30°C within 5 seconds.

[0015] Furthermore, the cooling medium in the rapid cooling process in step S2 is water.

[0016] In addition, the present invention also proposes a rapid separation system for steel-aluminum anode explosive weld blocks, including a scrap weld block storage area, a material cart conveying system, a heating furnace, a segmented cooling zone, and a magnetic separator. The material cart conveying system includes a material cart, a conveying track, a thrust system, a lifting device, and a tilting device. The conveying track connects the scrap weld block storage area, the heating furnace, the segmented cooling zone, and the magnetic separator. The material cart travels on the conveying track via the thrust system, picks up the material via the lifting device, lifts it up and transports it to a designated position, and then lowers it for unloading, or tilts the material into the segmented cooling zone via the tilting device. The segmented cooling zone includes a rapid evaporation cooling zone, a secondary water cooling zone, and an automatic shrinkage and peeling zone. The different zones in the segmented cooling zone are also connected by the conveying track.

[0017] Furthermore, the heating furnace is equipped with tiered racks.

[0018] Furthermore, the cooling zones in the segmented cooling zone are connected by supplementary pipelines. The cooling water from the automatic shrinking and stripping zone is supplied to the secondary water cooling zone, and the cooling water from the secondary water cooling zone is supplied to the rapid evaporation and cooling zone. The hot water and steam from the rapid evaporation and cooling zone are connected to the heating network or drying system. The cooling water at the end of the heating network or drying system is circulated to the automatic shrinking and stripping zone to complete the cooling water circulation.

[0019] This invention eliminates the need for external force by utilizing the surface tension difference between steel and aluminum. After uniformly heating the steel-aluminum anode explosion weld blocks, it rapidly cools them in stages. The surface contraction stress of the steel and aluminum causes automatic separation of the steel and aluminum. This method ensures thorough steel-aluminum separation, rapid separation speed, high efficiency, high recovery rate, and safe production. The composition of the recycled materials does not affect each other. Furthermore, the use of heating furnaces and magnetic separators allows for batch processing of waste materials, saving significant manpower and resources. This invention fulfills the need for rapid separation and classified recycling of steel-aluminum anode explosion weld blocks. Moreover, the system proposed in this invention fully utilizes the waste heat during the cooling process, meeting current energy conservation and environmental protection requirements. Attached Figure Description

[0020] The embodiments of the present invention will be further described below with reference to the accompanying drawings, wherein:

[0021] Figure 1 A schematic diagram illustrating the workflow of this method and system is shown. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0023] In one embodiment, a rapid separation system for steel-aluminum anode explosive weld blocks includes a scrap weld block storage area, a material cart conveying system, a heating furnace, a segmented cooling zone, and a magnetic separator. The heating furnace is equipped with a layered rack made of austenitic stainless steel, which can be stacked in multiple layers. The rack consists of a pallet and a bracket. The heating furnace can be an aluminum ash frying pan. The material cart conveying system uses a three-dimensional composite material cart, including a material cart, a conveying track, a thrust system, a lifting device, and a tilting device. The conveying track connects the scrap weld block storage area, the heating furnace, the segmented cooling zone, and the magnetic separator. The material cart travels on the conveying track via the thrust system, picks up materials via the lifting device, lifts them up and transports them to a designated position, and then lowers them for unloading, or tilts the materials into the segmented cooling zone via the tilting device. The segmented cooling zone includes a rapid evaporation cooling zone, a secondary water cooling zone, and an automatic shrinkage and peeling zone. Different zones in the segmented cooling zone are also connected by the conveying track. This system is used for the transfer and feeding / picking of steel-aluminum anode explosive weld blocks. The cooling zones in the segmented cooling zone are connected by supplementary pipelines. The cooling water from the automatic shrinking and stripping zone is supplied to the secondary water cooling zone, and the cooling water from the secondary water cooling zone is supplied to the rapid evaporation and cooling zone. The hot water and steam from the rapid evaporation and cooling zone are connected to the heating network or drying system. The cooling water at the end of the heating network or drying system is circulated to the automatic shrinking and stripping zone to complete the cooling water circulation. The drying system is specifically a drying system for recycled aluminum cold materials or cast discs.

[0024] The specific work process is as follows:

[0025] S1: The material car conveying system uses a lifting device to pick up scrap welding blocks from the scrap welding block storage area and load them onto a car. The car then runs on the conveying track to the heating furnace opening. The lifting device is used to add the scrap welding blocks into the heating furnace, where they are heated evenly to 550℃. The heating time is 20 minutes, and the holding time is 25 minutes.

[0026] S2: The heated steel-aluminum anode explosive weld block is removed using a lifting device and transported to the rapid evaporation and cooling zone. A tilting device is used to quickly pour the steel-aluminum anode explosive weld block into the rapid evaporation and cooling zone, reducing its temperature to below 100℃ within 5 seconds. The steel-aluminum anode explosive weld block is then quickly removed and added to the secondary water cooling zone, reducing its temperature to below 60℃ within 5 seconds. The steel-aluminum anode explosive weld block is then quickly removed and added to the automatic shrinkage and peeling zone, reducing its temperature to below 30℃ within 5 seconds. The cooling medium is tap water. If the cooling time is insufficient, fresh tap water at a temperature below 25℃ is added to the cooling zone.

[0027] S3: The cooled steel and aluminum anode explosion weld blocks are fed into the magnetic separator via the material car conveying system, and the steel and aluminum are separated and recycled by magnetic separation.

[0028] The steel separated by this method and system has an aluminum content of <0.1ppm and an iron content of <0.1ppm, and the entire process can process a large number of materials to be separated in only about 1 hour.

[0029] The foregoing descriptions have outlined some exemplary embodiments of the present invention. It is understood that these embodiments are merely illustrative and do not constitute a limitation on the scope of protection of the present invention. Features in these embodiments can be rearranged in suitable ways, and the resulting solutions remain within the scope of protection claimed by the present invention. All other embodiments obtained by those skilled in the art based on the foregoing embodiments without inventive effort, i.e., all modifications, equivalent substitutions, and improvements made within the spirit and principles of this application, fall within the scope of protection claimed by the present invention.

Claims

1. A rapid separation method for steel-aluminum anode explosive weld blocks, characterized in that, Includes the following steps: S1: Heat the steel-aluminum anode explosion welding block to 500-600℃, with a heating time not exceeding 25 minutes and a holding time of not less than 20 minutes; S2: The heated steel-aluminum anode explosive weld block is subjected to at least three levels of rapid cooling, with each level of cooling time not exceeding 5 seconds. The temperature after the first level of rapid cooling is not higher than 150°C, and the final temperature is not higher than 40°C. S3: The cooled material is separated and recycled using magnetic separation to separate steel and aluminum.

2. The rapid separation method for steel-aluminum anode explosive weld blocks according to claim 1, characterized in that, The heating process in step S1 is a uniform temperature rise process.

3. The rapid separation method for steel-aluminum anode explosive weld blocks according to claim 1, characterized in that, The heating time in step S1 is 10-20 minutes, and the holding time is 20-25 minutes.

4. The rapid separation method for steel-aluminum anode explosive weld blocks according to claim 1, characterized in that, The rapid cooling in step S2 is a three-stage gradient rapid cooling process. The first stage of rapid cooling reduces the temperature of the steel-aluminum anode explosive weld block to below 100°C within 5 seconds. The second stage of rapid cooling reduces the temperature of the steel-aluminum anode explosive weld block to below 60°C within 5 seconds. The third stage of rapid cooling reduces the temperature of the steel-aluminum anode explosive weld block to below 30°C within 5 seconds.

5. The rapid separation method for steel-aluminum anode explosive weld blocks according to claim 1, characterized in that, The cooling medium in the rapid cooling process in step S2 is water.

6. A rapid separation system for steel-aluminum anode explosive weld blocks, using the method described in any one of claims 1-5, characterized in that, The system includes a scrap welding block storage area, a material cart conveying system, a heating furnace, a segmented cooling zone, and a magnetic separator. The material cart conveying system includes a material cart, a conveying track, a thrust system, a lifting device, and a tilting device. The conveying track connects the scrap welding block storage area, the heating furnace, the segmented cooling zone, and the magnetic separator. The material cart travels on the conveying track via the thrust system, picks up materials via the lifting device, lifts them up, and transports them to a designated location, then lowers them to unload, or tilts the materials into the segmented cooling zone via the tilting device. The segmented cooling zone includes a rapid evaporation cooling zone, a secondary water cooling zone, and an automatic shrinkage and peeling zone. The different zones within the segmented cooling zone are also connected by the conveying track.

7. The system according to claim 6, characterized in that, The heating furnace is equipped with tiered racks.

8. The system according to claim 6, characterized in that, The segmented cooling zones are connected by supplementary pipelines. The cooling water from the automatic shrinking and stripping zone is supplied to the secondary water cooling zone, and the cooling water from the secondary water cooling zone is supplied to the rapid evaporation and cooling zone. The hot water and steam from the rapid evaporation and cooling zone are connected to the heating network or drying system. The cooling water at the end of the heating network or drying system is circulated to the automatic shrinking and stripping zone to complete the cooling water circulation.

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