TWI857569B - Method for manufacturing aluminum alloy deoxidizer - Google Patents

Abstract

A method for manufacturing aluminum alloy deoxidizer comprising steps of: filling and pressing several recycled aluminum pieces into a forming member until the forming member is filled, mounting the recycled aluminum pieces into a mold, pouring liquid aluminum fully covering the recycled aluminum pieces and forming a billet, preheating the billet and forming an aluminum rod with hot extrusion, and cutting the aluminum rod into several aluminum ingots and completing a recycled aluminum alloy deoxidizer.

Description

Method for producing deoxidized aluminum alloy material

A method for producing a deoxidized material, in particular a method for producing an aluminum alloy deoxidized material.

Circular economy has become a popular concept in modern society. Different from the traditional linear economic model, which is from resource mining to production, consumption and final disposal, the economic model based on resource recovery and reuse hopes to minimize resource consumption and waste. The circular economic model encourages the circular use of resources, realizes the maximum value of resources through resource recovery, regeneration and reuse, and realizes a sustainable economic development model.

Metal and related manufacturing industries are important resource consumers and sources of environmental pollution, so the implementation of a circular economy is crucial to the industry. Many related industries have already implemented metal recycling, because recycling metals can save a lot of raw materials and energy, reduce carbon emissions, and the recycled metals can be used to manufacture new products. However, today's aluminum recycling model requires the recycled aluminum to be smelted and tempered, which consumes extremely high energy, requires many operations, and has high operating costs. The oxidation caused by heating causes a loss of yield and wastes a lot of aluminum metal, and produces toxic fumes and slag when the scrap aluminum is remelted.

In addition, the recycled aluminum materials collected by the current aluminum recycling model, such as aluminum cans, aluminum foil packages, or aluminum scraps generated after machining and cutting by machine tools, are all mixed with a certain degree of organic matter due to the use requirements and characteristics of the recycled aluminum materials before recycling. For example, the inner surface of aluminum cans contains resin coatings and the outer printed coatings, or the waste aluminum scraps contain cutting fluids, etc. These organic substances attached to the recycled aluminum materials will produce organic pollutants such as dioxins during the remelting process of the recycled aluminum materials in the existing aluminum recycling process, causing serious environmental pollution and public hazards.

On the other hand, in the steel industry, in order to remove oxygen from molten steel, effectively improve the quality and performance of molten steel, increase the purity and uniformity of molten steel, reduce defects, and enhance the toughness and corrosion resistance of steel, deoxidizing materials are used in large quantities in the steelmaking process, especially aluminum alloys that can react quickly with oxygen as deoxidizing materials. However, the cost of aluminum alloys is relatively high, and the energy consumption of existing technologies for manufacturing aluminum alloy deoxidizing materials is also very high. In view of this, developing a method to reduce the generation of organic pollutants from the recycling of waste aluminum and practicing circular economy has become an urgent goal in related fields.

In order to solve the problem of environmental pollution caused by organic pollutants generated during the melting of waste aluminum in the existing aluminum recycling process, the present invention provides a method for making an aluminum alloy deoxidized material, which comprises the following steps: placing a plurality of recycled aluminum materials into a certain shape and compacting them until the recycled aluminum materials fill the certain shape; placing the compacted recycled aluminum materials into a mold; pouring an aluminum soup into the recycled aluminum materials and sealing them to form a casting bag; forming an aluminum bar by hot extrusion of the casting bag; and cutting the aluminum bar into a plurality of aluminum grains to complete an aluminum alloy deoxidized material.

The molded part is filled with recycled aluminum from a single source, and the recycled aluminum and the aluminum soup have the same alloy composition.

Among them, the recycled aluminum material is aluminum chips produced by aluminum alloy cutting processing.

The recycled aluminum material is shredded aluminum cans or aluminum foil packages.

The forming part is an aluminum alloy tube, and the recycled aluminum material and the forming part are composed of the same alloy, and the forming part filled with the recycled aluminum material is directly placed in the mold.

The ratio of the cross-sectional area of the molding to the aluminum strip is between 25:1 and 10:1.

Among them, the temperature of the hot extrusion is between 400℃ and 550℃.

Among them, the extrusion speed of the hot extrusion is between 0.2 meters per minute and 2 meters per minute.

Among them, the porosity of the aluminum strip is less than 1%.

The step of cutting the aluminum bar into a plurality of aluminum grains is performed in an oxygen-free environment.

The step of placing the recycled aluminum material into the shaped part further includes placing elements such as magnesium, manganese, silicon, zinc or copper into the shaped part.

From the above description, it can be seen that the present invention has the following features:

1. The method for producing aluminum alloy deoxidized material of the present invention does not require heating to melt the waste aluminum, which can greatly reduce the generation of organic pollutants such as dioxin and avoid the risk of organic pollutants escaping into the environment.

2. The method for making aluminum alloy deoxidized material of the present invention does not require heating to melt the scrap aluminum, which can save a lot of energy and will not produce toxic fumes and slag produced when the scrap aluminum is melted.

3. The method for producing aluminum alloy deoxidized material of the present invention does not require heating to melt the scrap aluminum, thus avoiding the yield loss caused by aluminum oxidation during the process.

4. The method for producing aluminum alloy deoxidized material of the present invention further uses recycled aluminum as a deoxidizer for steelmaking, and at the same time utilizes the high temperature of steelmaking to completely decompose the organic matter attached to the recycled aluminum, thereby reducing the production of dioxin and reducing the cost of deoxidizer and raw material consumption in the steelmaking process.

5. The production method of the aluminum alloy deoxidized material of the present invention will not produce organic pollutants during the production process because the recycled aluminum material contains organic matter. It can simplify or even eliminate the previous processing process of the recycled aluminum material, saving time, resources and costs, and is more environmentally friendly.

6. The aluminum alloy deoxidized material formed by the manufacturing method of the aluminum alloy deoxidized material of the present invention has a stable and dense crystal structure, which greatly improves the ductility and toughness of the aluminum alloy deoxidized material.

7. The manufacturing method of the aluminum alloy deoxidized material of the present invention does not need to fix the aluminum pressing block with an adhesive as in the previous technology, which can save costs and avoid environmental pollution and resource waste caused by adhesives.

8. The method for making the aluminum alloy deoxidized material of the present invention first makes the recycled aluminum material into aluminum bars and then cuts them into a plurality of aluminum grains, which can reduce the surface area of the aluminum alloy deoxidized material in contact with the atmosphere to reduce the generation of aluminum oxide and enhance the deoxidation effect of the deoxidized material.

9. The present invention reduces the buoyancy of the aluminum alloy deoxidized material by cutting the aluminum particles into concave and hollow shapes, making it easier for the aluminum particles to sink to the bottom of the steelmaking molten bath, and can increase the contact surface area, greatly improving the deoxidation effect.

10. The method for making the aluminum alloy deoxidized material of the present invention can further add other elements before hot extrusion to adjust the oxidation-reduction ability and specific gravity of the aluminum particles by adjusting the alloy composition, thereby improving the deoxidation effect of the deoxidized material.

11. The method for making aluminum alloy deoxidized material of the present invention can recycle aluminum waste that is difficult to process with the existing technology, such as aluminum chips produced by aluminum alloy cutting or used aluminum cans, solving the problem that these aluminum chips have a large surface area to volume ratio, making them easy to oxidize, and are often mixed with lubricants, cutting fluids or beverage residues and coatings, making them difficult to remelt and recycle with the existing technology.

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following is a brief introduction of the drawings required for the description of each embodiment. Obviously, the drawings described below are only some examples or embodiments of the present invention. For ordinary technicians in this field, the present invention can also be applied to other similar scenarios based on these drawings without creative work. Unless it is obvious from the language environment or otherwise explained, the same number in the figure represents the same structure or operation.

As shown in the present invention and claims, unless the context clearly indicates an exception, the words "a", "an", "a kind" or "the" do not refer to the singular, but also include the plural. Generally speaking, the terms "include" and "comprise" only indicate the inclusion of the steps and elements that have been clearly identified, and these steps and elements do not constitute an exclusive list, and the method or device may also include other steps or elements.

Flowcharts are used in the present invention to illustrate the operations performed by the system according to the embodiments of the present invention. It should be understood that the previous or subsequent operations are not necessarily performed in exact order. Instead, the steps can be processed in reverse order or simultaneously. At the same time, other operations can be added to these processes, or one or more operations can be removed from these processes.

Please refer to Figure 1, which is a step diagram of the present invention. The present invention mainly includes steps S10 to S50.

Step S10: Put a plurality of recycled aluminum materials into a certain molded part and compact them until the recycled aluminum materials fill the molded part. In this step S10, the collected recycled aluminum materials are concentrated and put into the molded part and continuously compacted. When the recycled aluminum materials shrink due to compression, more recycled aluminum materials can be put into the molded part until the recycled aluminum materials completely fill the molded part. Preferably, the molded part is a hollow tube, and the hollow tube can be a tube with openings at both ends or only one end. The cross-section of the hollow tube is circular. Preferably, the diameter of the cross-section circle of the hollow tube is 9 cm, and the length of the hollow tube is 60 cm.

The recycled aluminum material can be various recycled aluminum waste materials. For example, the recycled aluminum material can be aluminum chips generated during the cutting process of an aluminum alloy block, or recycled aluminum cans and aluminum foil package chips after pre-treatment and shredding. Preferably, the recycled aluminum materials filled in the hollow tube are all recycled aluminum materials from a single source. The so-called single source means that the recycled aluminum materials are all aluminum alloy waste materials of the same alloy system or the same American Aluminum Association alloy number. In one embodiment, the recycled aluminum materials filled in the molded part are aluminum alloy aluminum chips generated by the same cutting process performed by the same machine tool. In another embodiment, the recycled aluminum alloy cans with alloy number 3004 of the American Aluminum Association are shredded and placed in the molded part for compaction and filling.

Among them, the recycled aluminum material can be put into the molded part for compacting and filling after a series of pre-treatments. In one embodiment, the recycled aluminum material is preliminarily cleaned and air-selected to remove larger impurities, and then magnetically separated to remove ferromagnetic metals. However, these pre-treatments are not absolutely necessary, and appropriate pre-treatment methods can be selected depending on the source of the recycled aluminum material. For example, in one embodiment, the recycled aluminum material is aluminum chips generated by a cutting process of an aluminum alloy block, then the recycled aluminum material only needs to be preliminarily cleaned to roughly remove the cutting fluid before it can be put into the molded part for filling and compacting.

Therefore, the recycled aluminum material contains a plurality of residual organic compounds. In one embodiment, the recycled aluminum material is aluminum chips generated during a cutting process of an aluminum alloy block, and the plurality of residual organic compounds in the recycled aluminum material are mostly cutting fluids, which may contain mineral oil, emulsifier, water, anti-rust additives, defoaming agents and other ingredients. In another embodiment, the recycled aluminum material is recycled aluminum cans and aluminum foil bag scraps, and the multiple organic compounds remaining in the recycled aluminum material may be paper components contained in the aluminum foil bag, such as cellulose, hemicellulose or lignin, or the printed layer of the aluminum can body that has not been completely removed and the coating layer of the inner layer of the aluminum can. The components of the coating layer may be various lipids such as wax, or various resins such as epoxy resins, or various polyesters such as acrylic copolymers or polycarbonates. These organic compounds are difficult to be completely removed in the pre-treatment process without consuming a lot of time, energy and resources. However, in this step S10, the recycled aluminum material does not need to go through a complicated pre-treatment process before it can be placed in the molded part for compaction and filling.

In order to make the aluminum alloy deoxidized material formed by the present invention have a better effect, magnesium, manganese, silicon, zinc or copper and other elements can be added to the aluminum bag at the same time when the recycled aluminum material is placed in the coating material for filling and compacting to further improve its overall deoxidation effect and adjust the specific gravity of the aluminum alloy deoxidized material formed by the present invention. Preferably, different proportions of elements can be added according to different recycled aluminum materials to achieve a specified ratio, so that the aluminum bag contains 0.1 to 2 weight percent silicon, 0 to 2 weight percent copper, 0.1 to 30 weight percent magnesium, 0.1 to 10 weight percent manganese and 0 to 10 weight percent zinc elements.

Step S20: Place the compacted recycled aluminum into a mold. In this step S20, when the recycled aluminum has been compacted to fill the forming part, the compacted recycled aluminum is taken out from the forming part and placed in the mold. In this step S20, the recycled aluminum can be taken out from the forming part and placed in the mold. Since the recycled aluminum has been compacted, the recycled aluminum will maintain its shape in the coating material when taken out without scattering or deforming. Preferably, the coating material is the hollow tube, and the compacted recycled aluminum is a cylinder after being taken out. Place the compacted recycled aluminum into the mold. Among them, the mold is a long hollow cylinder, and its length and cross-section are both larger than the hollow tube. The bottom of the mold has a fixed ring placed at the center of a long axis. The fixed ring is equal to or slightly larger than the cross-section of the compacted recycled aluminum material, so that the fixed ring can fix the compacted recycled aluminum material at the center of the long axis of the mold without deviation. The mold may also include more than one clamping device so that the compacted recycled aluminum material can be stably fixed in the mold. In a preferred embodiment, the opening diameter of the mold is 12.7 cm, the mold is 60 cm long, and the bottom of the mold is provided with a fixed ring with a diameter of 10 cm and a depth of 1 cm, and the upper part of the mold is provided with an aluminum sheet and a screw for clamping. In a preferred embodiment, the mold fixes the compacted recycled aluminum material with an aluminum alloy tube.

In addition, in this step S20, the shaped part filled with the recycled aluminum material can be directly placed into the mold without taking the recycled aluminum material out of the shaped part. In a preferred embodiment, the shaped part is the hollow tube, and the hollow tube is made of aluminum alloy, so that the recycled aluminum material does not need to be taken out after the hollow tube is compacted, but is placed into the mold together with the hollow tube of aluminum alloy, and the hollow tube is used as the clamping device. More preferably, the hollow tube of aluminum alloy has the same alloy composition as the recycled aluminum material, that is, the hollow tube and the recycled aluminum material have the same alloy system or the same American Aluminum Association alloy number.

Step S30: pouring an aluminum soup into the recycled aluminum material and sealing it to form a casting bag. In this step S30, pouring an aluminum soup into the recycled aluminum material put into the mold, and the aluminum soup completely covers and seals the recycled aluminum material, and forms a casting bag after cooling and solidification. The aluminum soup is a molten aluminum alloy, and preferably, the aluminum soup and the recycled aluminum material have the same alloy composition, that is, the aluminum soup and the recycled aluminum material have the same alloy system or the same American Aluminum Association alloy number. In one embodiment, the recycled aluminum alloy can with alloy number 3004 of the American Aluminum Association is shredded and placed in the hollow tube to form a recycled aluminum material that is compacted and filled. In this step, the aluminum soup with alloy number 3004 of the American Aluminum Association is poured so that the aluminum alloy of the casting bag maintains the same homogeneous aluminum alloy properties. Preferably, the aluminum sheet used for compaction also has the same alloy composition as the recycled aluminum material. The aluminum soup completely seals the recycled aluminum material, so that a plurality of the organic compounds are coated in the casting bag.

Step S40: Preheat the casting bag and form an aluminum bar by hot extrusion. In this step S40, the casting bag is taken out of the mold and preheated as an aluminum blank, and is formed by hot extrusion to form an aluminum bar. The cross-sectional shape of the aluminum bar can be designed according to the requirements of an extrusion die through which the casting bag passes, and the hot extrusion can be direct extrusion or indirect extrusion. The indirect extrusion can produce a hollow structure inside the aluminum bar. Preferably, the temperature of the hot extrusion is between 400°C and 550°C, and the extrusion speed of the hot extrusion is between 0.2 meters per minute and 2 meters per minute; the so-called extrusion speed is the speed at which the aluminum bar is formed by hot extrusion. Preferably, the cross-sectional area ratio of the hollow tube to the aluminum bar is between 25:1 and 10:1; the cross-sectional area ratio of the hollow tube to the aluminum bar is the extrusion ratio, that is, the preferred extrusion ratio of this step S40 is between 10 and 25, and the porosity of the aluminum bar produced is less than 1%.

Step S50: Cut the aluminum bar into a plurality of aluminum grains to complete an aluminum alloy deoxidized material. In this step S50, the aluminum bar formed by hot extrusion is cut into a plurality of aluminum grains to complete the production of the aluminum alloy deoxidized material. The aluminum grains can be cut into round grains or polygons. Preferably, the aluminum grains can also include concave surfaces and hollows to increase the surface area of the aluminum grains, exert a better deoxidized material effect, and at the same time reduce buoyancy, so that the aluminum grains are easy to sink to the bottom of the smelting molten steel, increasing the deoxidation effect. In one embodiment, the aluminum bar formed by indirect hot extrusion in step S40 includes a hollow in the axial direction, so that when the aluminum bar is cut into a plurality of aluminum grains, the aluminum grains having through holes are formed.

Preferably, step S50 can be performed in an oxygen-free environment, such as cutting the aluminum bar into a plurality of aluminum grains and packaging them in a nitrogen environment, so that aluminum oxide will not form on the surface of the aluminum grains formed by cutting, thereby increasing the deoxidation capacity and efficiency of the aluminum alloy deoxidation material.

<Application of deoxidized aluminum alloy materials>

The aluminum alloy deoxidation material produced according to the manufacturing method of the present invention can be put into the blast furnace of steelmaking as the deoxidation material of molten steel. The temperature of the blast furnace of steelmaking is much higher than 900℃. Because the recycled aluminum material contains multiple residual organic compounds, the organic compounds still contained in the aluminum alloy deoxidation material can be completely cracked at this temperature, thereby avoiding the generation of toxic organic pollutants such as dioxin, and can effectively assist the deoxidation of molten steel.

From the above description, it can be seen that the present invention achieves the following effects:

1. The method for producing aluminum alloy deoxidized material of the present invention does not require heating to melt the waste aluminum, which can significantly reduce the generation of organic pollutants such as dioxin.

2. The method for making aluminum alloy deoxidized material of the present invention does not require heating to melt the scrap aluminum, which can save a lot of energy and will not produce toxic fumes and slag produced when the scrap aluminum is melted.

3. The production method of aluminum alloy deoxidized material of the present invention does not need to heat to melt the scrap aluminum, thus avoiding the yield loss caused by aluminum oxidation in the process. The existing technology of scrap aluminum recycling generates a high amount of new scrap, and the final recycled metal does not exceed 52%, while the recycling material utilization rate of the present invention is about 96%, which greatly increases the recyclable aluminum.

4. The method for producing aluminum alloy deoxidized material of the present invention further uses recycled aluminum as a deoxidizer for steelmaking, and at the same time utilizes the high temperature of steelmaking to completely decompose the organic matter attached to the recycled aluminum, thereby reducing the production of dioxin and reducing the cost of deoxidizer and raw material consumption in the steelmaking process.

5. The production method of the aluminum alloy deoxidized material of the present invention will not produce organic pollutants during the production process because the recycled aluminum material contains organic matter. It can simplify or even eliminate the previous processing process of the recycled aluminum material, saving time, resources and costs, and is more environmentally friendly.

6. The aluminum alloy deoxidized material produced by the manufacturing method of the present invention has a stable and dense crystal structure, which greatly improves the ductility and toughness of the aluminum alloy deoxidized material.

7. The manufacturing method of the aluminum alloy deoxidized material of the present invention does not need to fix the aluminum pressing block with an adhesive as in the previous technology, which can save costs and avoid environmental pollution and resource waste caused by adhesives.

8. The method for making the aluminum alloy deoxidized material of the present invention first makes the recycled aluminum material into aluminum bars and then cuts them into a plurality of aluminum grains, which can reduce the surface area of the aluminum alloy deoxidized material in contact with the atmosphere to reduce the generation of aluminum oxide and enhance the deoxidation effect of the deoxidized material.

9. The present invention reduces the buoyancy of the aluminum alloy deoxidized material by cutting the aluminum particles into concave and hollow shapes, making it easier for the aluminum particles to sink to the bottom of the steelmaking molten bath, and can increase the contact surface area, greatly improving the deoxidation effect.

10. The method for making the aluminum alloy deoxidized material of the present invention can further add other elements before hot extrusion to adjust the oxidation-reduction ability and specific gravity of the aluminum particles by adjusting the alloy composition, thereby improving the deoxidation effect of the deoxidized material.

11. The method for making aluminum alloy deoxidized material of the present invention can recycle aluminum waste that is difficult to process with the existing technology, such as aluminum chips produced by aluminum alloy cutting or used aluminum cans, solving the problem that these aluminum chips have a large surface area to volume ratio, making them easy to oxidize, and are often mixed with lubricants, cutting fluids or beverage residues and coatings, making them difficult to remelt and recycle with the existing technology.

It should be noted that, according to the explanation and elaboration of the above specification, the technical personnel in the field to which the present disclosure belongs can also change and modify the above implementation. Therefore, the present disclosure is not limited to the specific implementation disclosed and described above, and some equivalent modifications and changes to the present disclosure should also be within the scope of protection of the claims of the present disclosure. In addition, although this specification uses some specific terms, these terms are only for the convenience of explanation and do not constitute any limitation on the invention.

S10-S50: Steps

Figure 1 is a step diagram of an embodiment of the present invention.

S10-S50: Steps

Claims (11)

A method for making an aluminum alloy deoxidized material comprises the following steps: placing a plurality of recycled aluminum materials into a fixed part and compacting them until the recycled aluminum materials fill the fixed part; placing the compacted recycled aluminum materials into a mold; pouring an aluminum soup into the recycled aluminum materials and sealing them to form a casting bag; forming an aluminum rod by hot extrusion of the casting bag, wherein an extrusion ratio of the hot extrusion is greater than 10 to 1; and cutting the aluminum rod into a plurality of aluminum grains to complete an aluminum alloy deoxidized material. The method for manufacturing the aluminum alloy deoxidized material as described in claim 1, wherein the shaped part is filled with recycled aluminum material from a single source, and the recycled aluminum material and the aluminum soup have the same alloy composition. The method for producing aluminum alloy deoxidized material as described in claim 2, wherein the recycled aluminum material is aluminum chips produced by aluminum alloy cutting. The method for producing aluminum alloy deoxidized material as described in claim 2, wherein the recycled aluminum material is shredded aluminum cans or aluminum foil packages. The method for manufacturing an aluminum alloy deoxidized material as described in claim 2, wherein the molded part is an aluminum alloy tube, and the recycled aluminum material and the molded part are composed of the same alloy, and the molded part filled with the recycled aluminum material is directly placed in the mold. A method for manufacturing a deoxidized aluminum alloy material as described in any one of claim 1 to 5, wherein the ratio of the cross-sectional area of the molded part to the aluminum strip is between 25:1 and 10:1. A method for producing a deoxidized aluminum alloy material as described in claim 1 or 2, wherein the temperature of the hot extrusion is between 400°C and 550°C. The method for producing a deoxidized aluminum alloy material as described in claim 1 or 2, wherein the extrusion speed of the hot extrusion is between 0.2 meters per minute and 2 meters per minute. A method for manufacturing a deoxidized aluminum alloy material as described in claim 1, wherein the porosity of the aluminum strip is less than 1%. The method for manufacturing the deoxidized aluminum alloy material as described in claim 1, wherein the step of cutting the aluminum bar into a plurality of aluminum grains is performed in an oxygen-free environment. The method for making a deoxidized aluminum alloy material as described in claim 1, wherein the step of placing the recycled aluminum material into the shaped part further includes placing elements such as magnesium, manganese, silicon, zinc or copper into the shaped part.

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