Method for producing an aluminum deoxidizer, aluminum powder, and zinc oxide in a single batch process

Abstract

Provided is a method for producing an aluminum deoxidizer, aluminum powder, and zinc oxide in a single batch process. The present invention relates to a method for producing an aluminum deoxidizer, aluminum powder, and zinc oxide in a single batch process. The method includes a step of supplying gallium dross to an induction furnace and melting the gallium dross. The method includes a step of extracting zinc oxide powder, deoxidized aluminum, and aluminum powder from the molten gallium dross.

Description

Technical Field

[0001] The present disclosure relates to the field of treating gallium dross formed during the zinc plating process of steel. In particular, the present invention relates to, but is not limited to, a method for producing aluminum deoxidizer, aluminum powder, and zinc oxide from gallium dross in a single batch process.

Background Art

[0002] Gallium dross is a by-product generated in the step of zinc plating steel. Steel products are zinc plated to improve the corrosion resistance of steel. Zinc plating is widely used to coat steel, and the zinc plating process is performed by immersing the steel product in a bath of molten zinc and aluminum. In the zinc plating process, a large amount of zinc and aluminum are lost in the form of gallium dross, so new zinc and aluminum are added regularly. Gallium dross is a combination of free zinc and Zn-Fe-Al intermetallic compounds and is formed by multiple reactions between zinc, aluminum, and dissolved iron from the immersed steel product. Since gallium dross contains zinc and aluminum at high concentrations, it is a valuable by-product. However, due to the lack of technology and efforts to extract zinc and aluminum from gallium dross, zinc and aluminum resources are often wasted. In addition, the long-term storage of gallium dross causes long-term environmental problems.

[0003] Conventionally, a plurality of techniques for recovering zinc and aluminum from gallium dross by different extraction processes have been studied, and such techniques include, but are not limited to, distillation, electrolytic refining, leaching, supergravity technology, and the like. However, in such conventional techniques, separate and independent processes are used for each type of extraction to extract zinc, aluminum, silicon, iron, etc. from raw materials such as gallium dross. Therefore, manufacturers are producing aluminum deoxidizer / powder and zinc oxide, but manufacturing them in two different independent processes from two different raw materials in two different batches. These produce aluminum finished products from aluminum-containing raw materials and similarly produce zinc finished products from zinc-containing raw materials, and there is no relationship between them. In such conventional techniques, a huge amount of time and cost are required for the infrastructure for extracting aluminum powder, zinc oxide, etc. Therefore, there is a need for a process to produce aluminum deoxidizer / powder and zinc oxide from a single raw material, namely gallium dross, in a single batch process.

[0004] The present disclosure aims to overcome one or more of the above limitations and other limitations related to the prior art.

Summary of the Invention

[0005] The present invention provides a method for producing an aluminum deoxidizer, aluminum powder, and zinc oxide from gallium dross in a single batch process. The method includes the step of feeding gallium dross into an induction furnace to melt the gallium dross, where the gallium dross is received as a by-product. The received gallium dross is classified into any one of top-grade gallium dross, bottom-grade gallium dross, and gallium dross of a specified size, and the top-grade gallium dross and the bottom-grade gallium dross are classified based on the iron content of the received gallium dross. The method further includes the step of transferring the molten gallium dross to a silicon carbide crucible furnace and heating the molten gallium dross to a predetermined temperature, where when the molten gallium dross is heated, zinc vapor evaporates from the upper part of the molten gallium dross. The method includes the step of collecting the zinc vapor in an oxidation chamber to produce zinc oxide powder and adding pure aluminum to the residual molten metal based on the determination of the quality test of the molten metal, where the residual molten metal is the residual content after evaporating the zinc vapor from the molten gallium dross. The method further includes the step of casting the molten metal in a casting machine to produce an aluminum deoxidizer or aluminum powder.

[0006] The above summary is for illustrative purposes only and is not limiting in any way. In addition to the exemplary aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.

Brief Description of the Drawings

[0007] The novel features and characteristics of the present disclosure are set forth in the appended claims. However, the present disclosure itself, as well as its preferred modes of use, further objects and advantages, will be best understood by reference to the following detailed description of exemplary embodiments when read in conjunction with the drawings. Here, one or more embodiments are described by way of example only with reference to the drawings, in which the same reference numerals represent the same elements, and it is as follows.

Figure 1

Figure 2A

Figure 2B

Figure 3A

Figure 3B

DETAILED DESCRIPTION OF THE INVENTION

[0008] In this document, the term "exemplary" is used in the sense of "serving as an example, instance, or illustration". Any embodiment or implementation of the subject matter of the invention described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments.

[0009] Although the present invention is capable of various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will be described in detail below. It should be understood, however, that the disclosure is not intended to be limited to the disclosed form, but on the contrary, is intended to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the disclosure.

[0010] Terms such as "comprise," "comprising," or variations thereof are intended to cover non-exclusive inclusion, such that a setup, device, or process that includes a list of components or steps does not include only those components or steps but may include other components or steps not expressly listed or inherent to such setup, device, or process. In other words, one or more elements within a system or apparatus following "comprising" do not, without further limitation, preclude the existence of other elements or additional elements within the system or apparatus.

[0011] Embodiments of the present disclosure provide a method for manufacturing an aluminum deoxidizer, aluminum powder, and zinc oxide from gallium dross in a single batch process. The method includes the step of feeding gallium dross into an induction furnace to melt the gallium dross, where the gallium dross is received as a by-product. The received gallium dross is classified into either top-grade gallium dross, bottom-grade gallium dross, or gallium dross of a specified size before being fed into the induction furnace, and the top-grade gallium dross and bottom-grade gallium dross are classified based on the iron content of the received gallium dross. The method further includes the step of transferring the molten gallium dross to a silicon carbide crucible furnace and heating the molten gallium dross to a predetermined temperature, whereupon heating the molten gallium dross, zinc vapor evaporates from the top of the molten gallium dross. The method includes the step of collecting the zinc vapor in an oxidation chamber to produce zinc oxide powder and adding pure aluminum to the residual molten metal based on the determination of a quality test of the molten metal, where the residual molten metal is the residual content after evaporating the zinc vapor from the molten gallium dross. The method further includes the step of casting the molten metal in a casting machine to produce an aluminum deoxidizer or aluminum powder.

[0012] In the following paragraphs, the present disclosure will be described with reference to FIGS. 1 and 3B. In the figures, FIG. 1 is an exemplary method of the present disclosure, showing various steps of a method (100) for manufacturing an aluminum deoxidizer, aluminum powder, and zinc oxide in a single batch process. By this method (100), a manufacturer can produce an aluminum deoxidizer, aluminum powder, and zinc oxide from galvanium dross, which is a waste by-product of the zinc plating step of metal products, in a single batch process. Thus, in this method (100), it is not necessary to use two independent processes, two different batches, and two different raw materials to produce the aluminum deoxidizer / powder and zinc oxide from galvanium dross. In one embodiment, the method (100) according to the present disclosure helps to independently branch galvanium dross into secondary aluminum and zinc in a single batch process. Thus, by this method (100), a manufacturer can recycle galvanium dross with the most efficient technology. Further, in this method (100), only one set of machinery is required to produce both secondary aluminum and zinc oxide. Thus, the present invention saves cost, time, fuel, energy, floor space, and manual labor compared to conventional methods of manufacturing secondary aluminum and zinc.

[0013] However, those skilled in the art can understand that the size and configuration of the machinery set required to implement this method (100) can be changed according to the requirements of different types of installation environments. Any such changes / modifications shall be construed as being within the scope of the present disclosure.

[0014] As shown in FIG. 1, method (100) includes one or more blocks that are executed to manufacture aluminum deoxidizer, aluminum powder, and zinc oxide in a single batch process. The order in which method (100) is described is not intended to be construed as a limitation, and the described method blocks can be combined in any number and in any order to implement the method. Further, individual blocks can be removed from the method without departing from the spirit and scope of the subject matter described herein.

[0015] In block (102), gallium dross is fed into an induction furnace and melted. In one embodiment, the gallium dross is received as a by-product, and the gallium dross is available in the form of large blocks, and the weight of each block ranges from 50 kg to 1,500 kg depending on the source of the dross, i.e., the method of handling the dross at the factory that generates such dross. When the gallium dross is received, the gallium dross is classified into either top-grade gallium dross, bottom-grade gallium dross, or gallium dross of a specified size. The top-grade gallium dross and the bottom-grade gallium dross are classified based on the iron content of the received gallium dross. In one example, the top-grade gallium dross may include the chemical compositions of aluminum, zinc, iron, silicon, and copper in the proportions listed in Table 1.

[0016]

Table 1

[0017] In another example, the bottom-grade gallium dross can include the chemical compositions of aluminum, zinc, iron, silicon, and copper in the proportions listed in Table 2.

[0018]

Table 2

[0019] Furthermore, gallium dross is supplied to an induction furnace and melted. In one embodiment, in the case of top-grade gallium dross, the gallium dross is directly supplied to the induction furnace for melting. In the case of bottom-grade gallium dross, the gallium dross is cut into small pieces with each piece having a dimension of 21 inches or less, and such small pieces of bottom-grade gallium dross are directly transferred to a silicon carbide crucible furnace for processing. The top-grade gallium dross is supplied to the induction furnace using an overhead crane, and at this time, a crane with an appropriate capacity is used to safely transfer the top-grade gallium to the induction furnace. A set of iron hooks attached to the block of top-grade gallium dross is removed as soon as possible to prevent iron from accumulating in the metal tank.

[0020] An induction furnace is an electric furnace that induction-heats gallium dross to apply heat. The capacity of the induction furnace ranges from less than 1 kilogram to 100 tons and is used for melting steel, copper, aluminum, and precious metals. Compared with most other metal melting methods, the induction furnace provides a clean, energy-efficient, and properly controlled melting process. The induction furnace operates on the principle of induction heating and non-contact heating of conductive materials. Therefore, in an induction furnace, there is no need to burn fuel or other external heat sources.

[0021] Therefore, the received gallium dross is melted in the induction furnace. Furthermore, the process of melting the received gallium dross is performed in steps as shown in Figure 2A.

[0022] In block (202), a flux additive is added to the molten gallium dross. In one embodiment, a flux additive in the form of a mixture of cover flux (1.5% of the induction furnace batch weight) and sodium cryolite (0.5% of the induction batch weight) is added to the bath, i.e., the molten gallium dross. As a result, the upper surface of the molten gallium dross is covered with the flux, minimizing the oxidation of the metal.

[0023] In block ((204), slag is removed from the molten gallium dross. In one embodiment, the slag is a composite solution of silicate and oxide that is generated when the gallium dross melts and solidifies upon cooling. Removing the slag from the molten gallium dross helps remove impurities and protects the refractory lining of the induction furnace from excessive wear.

[0024] After removing the slag from the upper part of the molten gallium dross, the slag-free molten gallium dross is further processed as shown in Figure 1.

[0025] In block (104), the slag-free molten gallium dross is transferred to a silicon carbide crucible furnace. In one embodiment, the slag-free molten gallium dross is transferred to a silicon carbide crucible furnace to process the molten gallium dross at a high temperature. The silicon carbide crucible furnace is designed to achieve high-precision high-temperature uniformity and efficiently indirectly heat non-ferrous metals. Silicon carbide is a ceramic material with relatively high electrical conductivity compared to other ceramics.

[0026] In the process of transferring the slag-free molten gallium dross to the silicon carbide crucible furnace, the induction furnace is tilted 90 degrees, and the molten gallium dross flows through a trough and is filled into a ladle. Further, the molten gallium dross is transferred from the ladle to the silicon carbide crucible furnace. In the case of bottom gallium dross, the solid bottom gallium dross is directly supplied to the silicon carbide crucible furnace and melted.

[0027] Therefore, the upper gallium dross is first added to the induction furnace for melting, and then the molten metal of the gallium dross is transferred to the silicon carbide crucible furnace. The induction furnace is a furnace with a larger size compared to the silicon carbide crucible furnace. Therefore, the induction furnace can accommodate larger-sized gallium dross pieces and can melt larger-sized gallium dross pieces without cutting them into smaller sizes. Also, using the induction furnace reduces the fuel cost compared to the silicon carbide crucible furnace and saves the time of the silicon carbide crucible furnace, thus increasing the production of zinc and secondary aluminum. However, if the induction furnace is occupied by other working materials or under maintenance, or if a larger amount of gallium dross than the amount that can be transferred by the induction furnace is required in multiple silicon carbide crucible furnaces, etc., the upper gallium dross can be directly melted in the silicon carbide crucible furnace as needed.

[0028] In block (106), the molten gallium dross is heated to a predetermined temperature and zinc vapor evaporates. In one embodiment, the molten gallium dross is further heated in the silicon carbide crucible furnace. The molten gallium dross is heated to a predetermined temperature range of 1300°C to 1400°C to boil the metal of the molten gallium dross. When the molten gallium dross is heated, zinc vapor evaporates from above the molten gallium dross. Since the boiling point of zinc is 907°C, it is converted into a gas, while the boiling points of the other metals in the gallium dross, namely aluminum (Al), silicon (Si), iron (Fe), and copper (Cu), are 2470°C, 2355°C, 2862°C, and 2560°C, respectively. Since the boiling point of zinc is lower than that of the other metal elements (Al, Si, Fe, Cu) contained in the gallium dross, only zinc evaporates to form zinc vapor, and the other metals remain in a molten state in the crucible.

[0029] In block (108), zinc vapor is collected in an oxidation chamber to produce zinc oxide powder. In one embodiment, the zinc vapor is collected in the oxidation chamber where it reacts with oxygen in the air to produce zinc oxide vapor. Further, the process of collecting the zinc oxide vapor is carried out in steps as shown in Figure 2B.

[0030] In block (212), the zinc oxide vapor is transported through a long pipe and cooled. In one embodiment, the zinc oxide vapor is transported through a 400-foot-long pipe and cooled to form a fine white solid powder, i.e., zinc oxide powder.

[0031] In block (214), the zinc oxide powder is collected in a pulse jet air bag house. In one embodiment, the solid powdered zinc oxide is discharged from the pulse jet air bag house. The pulse jet air bag house or pulse jet dust collector is a self-cleaning dry filtration system. The pulse jet dust collector cleaning system removes particulate matter and dust from the surface of the internal filter media by injecting compressed air. The pulse jet type dust collector is used because it is easy to operate, has low energy consumption, and requires minimal maintenance.

[0032] In block (216), the zinc oxide powder is passed through a blender. In one embodiment, when the pulse jet filtration of the zinc oxide powder is completed, the zinc oxide powder is passed through a blender, and the bulk density of the zinc oxide powder increases.

[0033] In block (218), the quality of the zinc oxide powder is determined. In one embodiment, according to standard quality steps, the quality of zinc oxide is periodically checked multiple times by each quality assurance team in the laboratory under the same heating conditions. After determining the quality, the zinc oxide is weighed and packed in 25 kg HDPE bags.

[0034] As an example, zinc oxide produced from gallium dross is evaluated to have a purity within the range shown in Table 3.

[0035]

Table 3

[0036] Therefore, zinc oxide white seal grade is produced as a finished product applied to the manufacture of ceramics, rubber, and paints.

[0037] When the evaporation of zinc from the upper part of the molten gallium dross is completed, the remaining molten metal is further processed as shown in FIG. 1.

[0038] In block (110), based on the quality of the molten metal, pure aluminum is added to the remaining molten metal. In one embodiment, the process of adding pure aluminum to the remaining molten metal is performed in steps as shown in FIG. 3A.

[0039] In block (302), a flux additive is added to the remaining molten metal. In one embodiment, when the evaporation of zinc is completed, a pink cover flux, which is a flux additive, is added to the remaining molten metal and the mixture is stirred. The remaining molten metal is the residue after evaporating zinc vapor from the molten gallium dross, and the residue contains secondary aluminum with small amounts of other elements such as Si, Fe, and Cu.

[0040] Typically, secondary aluminum is made from recycled aluminum scrap obtained from all kinds of aluminum products and profiles such as aluminum turnings, aluminum sheets, aluminum chips, aluminum radiators, cast aluminum, extruded products, painted siding, and aluminum dross. Generally, secondary aluminum has a high tolerance for alloying elements such as iron, magnesium, and silicon.

[0041] In block (304), slag is removed from the remaining molten metal. In one embodiment, slag is removed from the remaining molten metal manually or using power tools.

[0042] In block (306), the chemical composition of the slag-free residual molten metal is evaluated. In one embodiment, a sample of the residual molten metal is evaluated for its chemical composition by a quality assurance team using laboratory-quality equipment such as an optical emission spectrometer (OES).

[0043] OES is used to immediately know the chemical composition of finished products and raw materials. OES is a highly reliable and widely used analytical instrument used to determine the elemental composition of a wide range of metals. The types of samples tested using OES include samples of melts in primary and secondary metal production, tubes, bolts, rods, wires, plates, etc. in the metal processing industry. OES can analyze a wide range of elements from hydrogen to uranium in solid metal samples covering a wide concentration range, achieving very high accuracy, high precision, and low detection limits.

[0044] The quality test helps to determine whether the chemical composition of the residual molten metal meets the customer's requirements.

[0045] In block (308), pure aluminum is added to the residual molten metal based on the evaluation. In one embodiment, when a discrepancy with the customer's requirements is found, pure aluminum is added to the silicon carbide crucible furnace to achieve the desired composition of the residual molten metal. A sample of the residual molten metal is taken again and evaluated by OES to confirm that the chemical composition of the molten metal complies with the customer's requirements. If the received quality is not as expected, aluminum ingots or aluminum scrap with a purity of 99.5% are added to the remaining molten metal and the mixture is stirred and homogenized. When pure aluminum is added, a sample of the residual molten metal is taken again and its chemical composition is checked using OES.

[0046] Therefore, by adding pure aluminum to the residual molten metal, the quality of secondary aluminum is improved.

[0047] When the quality test is completed and the quality of the target secondary aluminum is determined, the remaining molten metal is further processed as shown in Figure 1.

[0048] In block (112), an aluminum deoxidizer / aluminum powder is produced by casting or atomizing the residual molten metal.

[0049] In one embodiment, when the quality of secondary aluminum is finally determined, the residual molten metal is cast into a mold of a desired shape, and an aluminum deoxidizer of the desired shape is obtained. When making a shape like a shot, the molten metal is transferred to a shot casting machine like a homemade chakali, where the molten metal passes through the holes in the tray and solidifies upon cooling to form droplets called shots or granules. In the case of an aluminum ingot, cube, or hemisphere, the molten metal is poured into a customized mold having the respective shape and size according to the customer's requirements. Further, the aluminum deoxidizer is packed in 50 kg HDPE woven bags or 1 MT jumbo HDPE bags according to the customer's request.

[0050] As an example, an aluminum deoxidizer produced from galvanum dross (low iron content) is evaluated to have a chemical composition in the proportions shown in Table 4.

[0051] [Table 4]

[0052] As an example, an aluminum deoxidizer produced from bottom galvanum dross (high iron content) is evaluated to have a chemical composition in the proportions shown in Table 5.

[0053] [Table 5]

[0054] The aluminum deoxidizer produced from galvanum dross is a deoxidizer used for deoxidizing molten steel and improving the quality of steel. Molten steel contains dissolved oxygen, and it is important to remove it during the melting stage. Otherwise, porosity will occur in the solid steel, and the tensile strength of the steel will decrease.

[0055] In another embodiment, the residual molten metal is processed to produce aluminum powder. The process of manufacturing aluminum powder from the residual molten metal is carried out in steps as shown in Figure 3B.

[0056] In block (312), the residual molten metal is transferred to a holding furnace. In one embodiment, the holding furnace is used to further process the molten metal. The holding furnace is a heated reservoir for holding the molten metal in preparation for casting.

[0057] In block (314), the molten aluminum is atomized to form fine aluminum shots. In one embodiment, a jet of high-pressure air is used within the holding furnace to atomize the molten metal into fine molten particles or shots, which are then cooled ambiently to form a solid powder, i.e., aluminum powder.

[0058] In block (316), the fine aluminum shots are collected in a collection chamber. In one embodiment, the fine aluminum shots are collected in a collection chamber attached to the holding furnace. In one embodiment, the fine aluminum shots are collected in a collection chamber attached to the holding furnace. The hot air from the chamber is sucked in by a 3HP fan.

[0059] In block (318), the fine aluminum shots are sieved into various sizes. In one embodiment, the aluminum powder in the form of fine aluminum shots is sieved into various sizes and packed into 25 Kg HDPE bags. The finer aluminum powder is collected by a cyclone located between the fan and the collection chamber. The fine aluminum shots are used for various applications.

[0060] In one example, the aluminum powder produced from gallium dross is evaluated to have a chemical composition in the proportions shown in Table 6.

[0061]

Table 6

[0062] Aluminum powder produced by the spray method is used in various applications such as the production of ferroalloys such as ferromanganese and ferrochrome. During the production of ferroalloys, aluminum powder is added to cause a thermite reaction, which is an exothermic reaction that generates the extreme heat required for the production of ferroalloys. Aluminum powder can also be used for the same purpose in the firecracker industry. In the aforementioned applications, the size of the aluminum powder varies in the range of -10 mesh to +100 mesh.

[0063] Furthermore, finer aluminum powder with a mesh size of -200 mesh is used in the production of aluminum phosphide (ALPHOS), which is a fumigant. Aluminum powder with a mesh size of -300 mesh is used in the production of AAC blocks (aeration autoclave blocks).

[0064] In the experiment, information related to each process cycle is recorded. In an exemplary figure, each process cycle of the silicon carbide crucible furnace, i.e., a batch, is called a heat, and a heat number is assigned. The weight of each heat is 800 kg as input in the molten state (in the case of the upper gallium dross) or the solid state (in the case of the lower gallium dross). The manufacturing steps of each heat consist of four steps: filling, oxidation, sampling, and casting. In the filling step, the feedstock is heated to boil at 1400 °C. The filling process takes 1 hour when supplying molten metal from an induction furnace to the silicon carbide crucible furnace, and 4 hours when directly melting the solid dross. Furthermore, the oxidation process takes about 6 hours, during which zinc vapor reacts with oxygen to form zinc oxide. Furthermore, the sampling process takes about 0.5 hour, and the casting process takes about 1.5 hours. Therefore, the total time per heat is about 12 hours, but this time can be shortened to about 9 hours when directly transferring the molten metal to the silicon carbide crucible furnace. Also, when making aluminum into powder, since the molten metal is immediately transferred to the holding furnace, 1 hour of the casting time in the process cycle is saved, and the total heating time is shortened to about 8 hours.

[0065] In another example, for an input of 100 kg of top galvalume dross, it is observed that the finished product received as output, i.e., aluminum and zinc, is 98 kg. When using bottom galvalume dross as the input, 95 kg of finished product is obtained. Therefore, the yield of top galvalume dross is 98% and the yield of bottom galvalume dross is 95%.

[0066] In yet another example, the slag formed on the molten galvalume dross contains both metallic and non-metallic components. The slag is placed in a steel container and transported to a shed using a combination of a crane and rails. The slag is further processed by a vibrating machine to disperse the internal heat of the slag, agglomerate the metallic components, convert the metallic components into a liquid, and this liquid is poured from the vibrating machine into a mold to form an ingot. The remaining material is cooled for several hours, further passed through a ball mill, and then through a crusher to further separate the remaining metallic and non-metallic components. The metal content recovered from the slag is remelted in an induction furnace, transferred to a silicon carbide crucible furnace, zinc is removed by oxidation, and the remaining aluminum is cast. Advantages of the present disclosure:

[0067] The present invention provides a method (100) that enables a manufacturer to produce aluminum deoxidizer, aluminum powder, and zinc oxide from galvalume dross, which is a waste byproduct of the zinc plating process of metal products, in a single batch process. Thus, in this method (100), there is no need to use two independent processes, two different batches, and two different raw materials to produce aluminum deoxidizer / powder and zinc oxide.

[0068] Also, this method (100) helps to separate gallium dross into secondary aluminum and zinc independently in a single batch process. Thus, this method (100) creates new uses for gallium dross. This method (100) also enables manufacturers to recycle gallium dross in the most efficient and environmentally friendly way. Also, the use of gallium dross results in a significant cost reduction compared to the cost of raw materials used in independent manufacturing processes for producing aluminum deoxidizer, aluminum powder, and zinc oxide.

[0069] This method (100) provides a significant cost advantage to manufacturers as it can substantially reduce raw material costs compared to competing manufacturers. Thus, manufacturers can sell secondary aluminum and zinc at a lower price than other producers.

[0070] Furthermore, in this method (100), only one set of machinery is required to produce both secondary aluminum and zinc oxide. Thus, the present invention saves cost, time, fuel, energy, floor space, and manual labor compared to conventional methods of manufacturing secondary aluminum and zinc.

[0071] In the detailed description of embodiments of the present disclosure, reference is made to the accompanying drawings which form a part hereof and which illustrate specific embodiments in which the present disclosure may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the present disclosure, and it is to be understood that other embodiments may be utilized and that changes may be made without departing from the scope of the present disclosure. Accordingly, this description should not be construed in a limiting sense. Equivalents:

[0072] Regarding the use of substantially any plural and / or singular terms herein, those skilled in the art can translate from plural to singular and / or from singular to plural depending on context and / or application. For clarity, various singular / plural permutations may be explicitly set forth herein. Generally, it will be understood by those skilled in the art that the terms used herein, particularly in the appended claims (e.g., the body of the appended claims), are generally intended to be open terms (e.g., the term "comprising" should be interpreted as "comprising but not limited to", the term "having" should be interpreted as "having at least", the term "including" should be interpreted as "including but not limited to", etc.). Further, it will be understood by those skilled in the art that if a specific number of introductions of a claim is intended, such intent will be expressly recited in the claim, and if there is no such recitation, then such intent does not exist. For example, for purposes of illustration, the following appended claims may use introductory phrases such as "at least one" and "one or more" to introduce the claim recitations. However, the use of such phrases should not be construed to mean that the introduction of a claim recitation by the indefinite article "a" or "an" limits the particular claim containing the introduced claim recitation to an invention having only one such recitation. Even if the same claim contains both the introductory phrase "one or more" or "at least one" and the indefinite article "a" or "an" (e.g., "a" and / or "an" should generally be interpreted as meaning "at least one" or "one or more"). The same is true for the use of the definite article used to introduce a claim recitation.

[0073] Furthermore, even when a specific number of introduced claims is explicitly recited, one of ordinary skill in the art would recognize that such a recitation should typically be construed to mean at least the recited number (e.g., a mere recitation of "two recitations" without other modifiers would typically mean at least two recitations, or two or more recitations). Further, when a rule similar to "at least one of A, B, C, etc." is used, generally such an interpretation is intended in the sense that one of ordinary skill in the art would understand the rule (e.g., a system including "at least one of A, B, C" would include a system including only A, only B, only C, both A and B, both A and C, both B and C, and / or both A, B, and C, etc., but is not limited thereto). When a rule similar to "at least one of A, B, C, etc." is used, generally such an interpretation is intended in the sense that one of ordinary skill in the art would understand the rule (e.g., a system including "at least one of A, B, C, etc." would include a system including only A, only B, only C, both A and B, both A and C, both B and C, and / or all of A, B, and C, etc., but is not limited thereto). Further, one of ordinary skill in the art should be able to understand that in substantially any disjunctive and / or clause presenting two or more alternative terms, in any of the description, claims, or drawings, it is contemplated to include one of the terms, any of the terms, or both terms. For example, the phrase "A or B" is understood to include the possibility of "A" or "B" or "A and B".

[0074] Although various aspects and embodiments are disclosed herein, other aspects and embodiments will be apparent to one of ordinary skill in the art. The various aspects and embodiments disclosed herein are for illustrative purposes only and not limiting, and the true scope and spirit are set forth by the following claims.

Claims

1. A method for recovering aluminum and zinc from gallium dross in a single batch process, comprising: feeding the gallium dross into an induction furnace to melt the gallium dross and receiving the gallium dross as a by-product; transferring the molten gallium dross to a silicon carbide crucible furnace and heating the molten gallium dross to a predetermined temperature, wherein when the molten gallium dross is heated, zinc vapor evaporates from above the molten gallium dross; collecting the zinc vapor in an oxidation chamber to produce zinc oxide powder; adding pure aluminum to the molten metal residue based on the results of a quality test of the molten metal, wherein the molten metal residue is the residue after evaporating zinc vapor from the molten gallium dross; casting the molten metal with a casting machine to produce the aluminum deoxidizer or the aluminum powder.

2. The received gallium dross is classified into any one of top-grade gallium dross, bottom-grade gallium dross, and gallium dross of a specified size, and the top-grade gallium dross and the bottom-grade gallium dross are classified based on the iron content of the received gallium dross. The method according to claim 1.

3. The top-grade gallium dross is directly fed into the induction furnace for melting. In the case of the bottom-grade gallium dross, the bottom-grade gallium dross is cut into small pieces with each piece having a dimension of 21 inches or less, and such small pieces of the bottom-grade gallium dross are directly transferred to a silicon carbide crucible furnace for processing. The method according to claim 1.

4. The step of melting the received gallium dross comprises: adding a flux additive of a mixture of cover flux and sodium cryolite to the molten gallium dross and covering the upper part of the molten gallium dross with the flux to minimize the oxidation level; removing slag from the upper part of the molten gallium dross. The method according to claim 1.

5. The step of transferring the molten gallium dross to a silicon carbide crucible furnace is: A step of tilting the induction furnace by 90 degrees, wherein the molten gallium dross flows through a trough and is filled into a ladle, and said step; The method according to claim 1, comprising: a step of transferring the molten gallium dross from the ladle to the silicon carbide crucible furnace.

6. The method according to claim 1, wherein the molten gallium dross is heated to a predetermined temperature range of 1300 °C to 1400 °C to boil the metal in the molten gallium dross.

7. The step of collecting zinc vapor in the oxidation chamber is a step of transporting zinc oxide generated by oxidation of the zinc vapor through a 400-foot-long pipe, cooling it to form fine white solid zinc oxide powder; a step of collecting the zinc oxide powder in a pulse jet air bag house; a step of determining the quality of the zinc oxide powder based on a predefined criterion; The method according to claim 1, comprising: a step of passing the zinc oxide powder through a blender to increase the bulk density of the zinc oxide powder.

8. The step of adding pure aluminum to the residual molten metal is a step of adding a flux additive to the residual molten metal; a step of removing slag from the upper part of the residual molten metal; a step of evaluating the chemical composition of the slag-free residual molten metal sample by performing a quality test on the slag-free residual molten metal sample; The method according to claim 1, comprising: adding pure aluminum to the residual molten metal based on the evaluation of the chemical composition of the residual molten metal to achieve a desired composition of the residual molten metal.

9. The method according to claim 1, wherein the residual molten metal is cast into a mold of a desired shape to obtain an aluminum deoxidizer of the desired shape.

10. The step of manufacturing aluminum powder from the molten metal is a step of transferring the molten aluminum to a holding furnace; a step of atomizing the molten aluminum by injection of high-pressure air to form fine aluminum shots; a step of collecting the fine aluminum shots in a collection chamber attached to the holding furnace; The method according to claim 1, comprising: a step of sieving the fine aluminum shots into various sizes.

Images