Valuable metal recovery method for recovering valuable metals from waste batteries

Abstract

The present invention provides a method for recovering valuable metals contained in waste batteries, which can suppress the reduction of recovery rate and effectively recover valuable metals. The valuable metal recovery method for recovering valuable metals from waste batteries of the present invention comprises: a roasting step (S1), roasting waste batteries; a crushing step (S2), loading the roasted material into a crushing container and crushing it using a chain mill; and a screening step (S3), screening the crushed material and separating it into screened material and screened material. Among them, the chain mill device (2) used for the crushing process comprises: a rotating shaft rod (21), which is vertically erected relative to the bottom surface (1F) of the crushing container (1); and a chain (22), which is installed on the side of the rotating shaft rod (21), and the chain mill has a structure capable of adjusting the installation height (H) of the chain (22) in the rotating shaft rod (21).

Description

Technical Field

[0001] The invention relates to a method for recovering valuable metals contained in waste batteries. Background Art

[0002] In recent years, lithium-ion batteries have become popular as lightweight and high-power secondary batteries. The basic structure of a lithium-ion battery is a negative electrode current collector made of copper foil and a positive electrode current collector made of aluminum foil inside an outer can made of metal such as aluminum or iron.

[0003] A negative electrode active material such as graphite is fixed on the surface of the negative electrode collector to form a negative electrode material. In addition, a positive electrode active material such as lithium nickelate or lithium cobaltate is fixed on the surface of the positive electrode collector to form a positive electrode material. The negative electrode material and the positive electrode material are placed in the above-mentioned outer can via a separator composed of a porous resin film of polypropylene, etc., and an electrolyte containing an electrolyte such as lithium hexafluorophosphate (LiPF6) is sealed in the gap.

[0004] Lithium-ion batteries are currently used as batteries for hybrid vehicles, electric vehicles, etc. However, lithium-ion batteries installed in vehicles gradually deteriorate with repeated use and eventually reach the end of their service life and are discarded.

[0005] As the power of automobiles changes from gasoline to electricity, the number of batteries used in automobiles increases, and at the same time, the number of discarded batteries also increases.

[0006] There have been many attempts and specific proposals to recycle such discarded lithium-ion batteries or defective products generated during the manufacture of lithium-ion batteries (hereinafter collectively referred to as "waste batteries") as resources. In most cases, the mainstream process is a dry smelting process in which the waste lithium-ion batteries are put into a high-temperature furnace to melt them all.

[0007] Here, in addition to elements such as nickel, cobalt, and copper that are commercially valuable for recycling (hereinafter referred to as "valuable metals"), waste batteries also contain elements such as carbon, aluminum, fluorine, and phosphorus that are not commercially recycled (hereinafter collectively referred to as "impurities"). When recovering valuable metals from waste batteries, it is necessary to efficiently separate the impurities from the valuable metals.

[0008] Therefore, the following method is carried out: for example, after the waste batteries are roasted to remove fluorine, phosphorus, etc. for harmless treatment, they are crushed or pulverized, and then separated by a sifter or a magnetic separator, and the valuable metals are recovered from the separated product through the above-mentioned dry smelting process (hereinafter referred to as "dry treatment") or the wet smelting process using liquid separation such as acid and organic solvent (hereinafter referred to as "wet treatment").

[0009] As a method for recovering cobalt as a valuable metal from waste batteries by dry treatment, Patent Document 1, for example, proposes a process of placing waste lithium-ion batteries in a melting furnace and blowing in oxygen for oxidation.

[0010] Patent Document 2 proposes a process in which waste lithium-ion batteries are melted, slag is separated and valuables are recovered, and then a lime-based solvent (flux) is added to remove phosphorus.

[0011] In addition, Patent Document 3 discloses a recycling method for a battery box, wherein the battery box includes a battery pack formed by connecting a plurality of single cells in series and a control unit for controlling the battery pack, and has a resin component. The recycling method includes a step of directly baking the battery box containing the battery pack in a charged state, and a complete combustion step of completely burning the thermal decomposition gas of the unburned portion generated when baking the battery box. The baking temperature in the baking step is set above the carbonization temperature of the resin forming the resin component and below the melting point of the metal component of the battery box, and the battery pack in the battery box is baked in a non-oxidizing environment or a reducing environment.

[0012] However, these methods have the following problems: the dehydration or drying process, the main body of the device, and maintenance also require a lot of cost. In particular, if the appropriate crushing size cannot be maintained when crushing the waste battery, it is impossible to smoothly separate the fine powder containing a large amount of valuable metals and the lumps containing a large amount of impurities, thereby reducing the recovery rate of valuable metals.

[0013] Prior art literature

[0014] Patent Literature

[0015] Patent Document 1: Japanese Patent Application Publication No. 2013-091826

[0016] Patent Document 2: Japanese Patent Application No. 2013-506048

[0017] Patent Document 3: Japanese Patent Application Publication No. 2010-3512 Summary of the invention

[0018] Problems to be solved by the invention

[0019] The present invention has been proposed in view of such a situation, and its object is to provide a method for recovering valuable metals contained in waste batteries, which can suppress the reduction of the recovery rate and effectively recover the valuable metals.

[0020] Technical solutions to problems

[0021] The present inventors have conducted intensive studies to solve the above problems and have found that valuable metals can be effectively recovered by crushing the roasted material obtained by roasting waste batteries using a chain mill, thereby completing the present invention.

[0022] (1) The first invention of the present invention is a valuable metal recovery method for recovering valuable metals from waste batteries, comprising: a roasting step of roasting the waste batteries; a crushing step of placing the roasted products into a crushing container and crushing them using a chain mill; and a screening step of screening the crushed products and separating them into screened products and screened products.

[0023] (2) The second invention of the present invention is a valuable metal recovery method for recovering valuable metals from waste batteries. In the first invention, the chain mill used for the crushing process in the crushing step comprises: a rotating shaft rod, which is uprightly arranged relative to the bottom surface of the crushing container; and a chain, which is installed on the side of the rotating shaft rod, and the chain mill has a structure capable of adjusting the installation height of the chain in the rotating shaft rod.

[0024] (3) The valuable metal recovery method for recovering valuable metals from waste batteries according to the third invention of the present invention is, in the second invention, the chain is installed in the chain mill at an installation position in a range where the distance from the bottom surface of the crushing container is greater than 5 mm and less than 300 mm.

[0025] (4) The fourth invention of the present invention is a method for recovering valuable metals from waste batteries. In the second or third invention, in the chain mill, two or more mounting positions are provided on the side surface of the rotating shaft rod in its rotation direction, and the chain is installed at each mounting position.

[0026] (5) The fifth invention of the present invention is a valuable metal recovery method for recovering valuable metals from waste batteries. In any one of the first to fourth inventions, it also comprises: an oxidizing roasting step of oxidizing roasting the undersize material; and a reducing melting step of reducing and melting the oxidized roasted material to obtain slag and an alloy containing valuable metals.

[0027] (6) In the method for recovering valuable metals from waste batteries according to the sixth invention of the present invention, in any one of the first to fifth inventions, the valuable metals include at least one selected from the group consisting of cobalt, nickel and copper.

[0028] Effects of the Invention

[0029] According to the present invention, when valuable metals are recovered from waste batteries, it is possible to efficiently recover the valuable metals while suppressing a decrease in the recovery rate of the valuable metals. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1This is a process diagram showing an example of the flow of a valuable metal recovery method.

[0031] Figure 2 This is a diagram for explaining a crushing process using a chain mill. DETAILED DESCRIPTION

[0032] Hereinafter, a specific embodiment of the present invention (hereinafter referred to as "the present embodiment") will be described in detail. The present invention is not limited to the following embodiment, and various modifications can be made without changing the gist of the present invention.

[0033] 《1. Overview of Valuable Metal Recovery Methods》

[0034] The valuable metal recovery method of this embodiment is a valuable metal recovery method for recovering valuable metals from waste batteries. Generally, when recovering valuable metals from waste batteries, there is a case where wet treatment is performed in addition to dry treatment, but the valuable metal recovery method of this embodiment mainly involves dry treatment.

[0035] Specifically, the valuable metal recovery method is characterized in that after the waste battery is roasted for harmlessness, the roasted product obtained is placed in a crushing container and crushed using a chain mill. The crushed product obtained after the crushing process is subjected to screening to separate the undersize product (powdered product) containing a large amount of valuable metals and the oversize product containing impurities.

[0036] According to such a method, by crushing the roasted product using a chain mill, a powdery crushed product mainly containing valuable metals can be efficiently obtained, and the valuable metals can be efficiently recovered from the powdery undersize product through screening.

[0037] Here, as mentioned above, waste batteries are a concept of waste materials in the manufacturing process of lithium-ion batteries, including secondary batteries such as used lithium-ion batteries, defective products generated in the manufacturing process, residues in the manufacturing process, and waste generated in the manufacturing process. As mentioned above, such waste batteries contain valuable metals such as nickel, cobalt, and copper that have economic value for recycling and reuse.

[0038] 《2. Regarding each process of valuable metal recovery method》

[0039] Figure 1: is a process diagram showing an example of the flow of the valuable metal recovery method of this embodiment. The valuable metal recovery method comprises: a roasting step S1, roasting waste batteries; a crushing step S2, crushing the roasted product using a chain mill; and a screening step S3, screening the crushed product to separate it into a lump as an oversize product and a powder as a undersize product. Here, valuable metals such as nickel and cobalt are metals contained in the positive electrode active material, and since they are recovered in powder form, they are largely distributed in the undersize product.

[0040] In addition, the process further comprises: an oxidation roasting step S4 of oxidizing and roasting the screened product; and a reduction melting step S5 of reducing and melting the oxidized roasted product to obtain slag and an alloy (metal) containing valuable metals.

[0041] Furthermore, by subjecting the valuable metal alloy obtained through such a series of dry treatments to wet treatments such as neutralization treatment, solvent extraction treatment, and electrolytic extraction, impurity components remaining in the alloy can be removed and the valuable metals can be further refined and recovered as high value-added metals.

[0042] [Baking process]

[0043] The main purpose of the roasting step S1 is to remove the electrolyte components, namely the fluorine components, etc. contained in the waste battery to render it harmless, and also to facilitate crushing in the next step.

[0044] The conditions for the roasting treatment are not particularly limited, but from the viewpoint of ensuring harmlessness while making the waste battery brittle so as to facilitate crushing in the next step, the roasting temperature is preferably heated to 700°C or above. In addition, the upper limit of the roasting temperature is not particularly limited, but is preferably 1200°C or below. When the roasting temperature is too high, part of the iron used mainly for the waste battery shell will adhere to the inner wall of the roasting furnace body such as the kiln, which may hinder smooth operation or may cause the kiln itself to deteriorate, so it is not preferred.

[0045] In addition, when too many waste batteries for roasting are piled up in the furnace, the inside cannot be roasted, resulting in uneven roasting. Therefore, from the perspective of uniform roasting, it is preferred to select the processing capacity, heating capacity of the roasting furnace, etc. For example, it is preferred to conduct preliminary tests in advance to determine the optimal temperature and roasting time.

[0046] The heating method during calcination is not particularly limited, and may be an electrical method or a burner method using a fuel such as oil or gas. In particular, a burner method is preferred because of its low heating cost.

[0047] [Crushing process]

[0048] In the crushing step S2, the calcined product obtained by calcining the waste battery in the calcining step S1 is crushed and finely separated. At this time, the valuable metal recovery method of this embodiment is characterized in that the calcined product is placed in a crushing container and crushed using a chain mill.

[0049] In this way, by using the chain mill as a crushing device to crush the roasted material, the powder containing a large amount of valuable metals can be easily separated from other impurities that are not the object of recovery in the obtained crushed material. In addition, in the screening step S3 of the next process, by screening the obtained crushed material into undersize and oversize, the valuable metals can be effectively recovered from the undersize. Moreover, since the crushing process using the chain mill can be finely crushed, the loss caused by the attachment of valuable metals to the lumps mainly composed of impurities can be prevented, and thus the reduction in the recovery rate can be suppressed.

[0050] (About chain grinding machine)

[0051] Figure 2 FIG. 1 is a diagram for explaining an example of crushing processing using a chain mill. Figure 2 As shown, the crushing process is performed inside a crushing container 1 having a chain mill device 2. The crushing container 1 has a sample input port 11, a sample recovery port 12, and a gas supply and exhaust pipe 13. In addition, a chain mill device 2 is provided in the processing space inside the crushing container 1.

[0052] In the crushing container 1, the roasted material to be crushed is put in from the sample inlet 11 and supplied to the chain mill device 2 to be described later provided in the processing space inside. The crushed material obtained after the crushing process by the chain mill device 2 is recovered from the sample recovery port 12. In addition, during the crushing process, the gas is exhausted and supplied from the gas supply and exhaust pipe 13 provided in the upper part (ceiling part) of the crushing container 1, and the ambient gas can be adjusted.

[0053] The chain mill device 2 has a rotating shaft rod 21 vertically erected relative to the bottom surface 1F inside the crushing container 1, and a chain 22 installed on the side of the rotating shaft rod 21. In the chain mill device 2, the chain 22 installed on the rotating shaft rod 21 rotates, and the roasted object to be crushed collides with the chain 22 bent as it rotates, so that the roasted object is crushed into a predetermined size. Since the bent chain 22 collides with the roasted object and crushes it, it can be crushed more strongly than other conventionally known crushing devices.

[0054] Rotating shaft rod

[0055] More specifically, the rotating shaft rod 21 is provided with a chain 22, which will be described later, at a predetermined position on the side thereof, and the chain installed on the side thereof is rotated in the processing space by rotating around the shaft. In addition, the number of chains installed on the rotating shaft rod 21 is not particularly limited, and preferably is more than 2. This aspect will be described later.

[0056] The rotating shaft rod 21 is vertically erected from the bottom surface 1F inside the crushing container 1. Therefore, the installation height ( Figure 2 The height (indicated as “H”) refers to the height based on the bottom surface 1F of the crushing container 1 , and is the distance from the bottom surface 1F of the crushing container 1 to the installation position of the chain 22 .

[0057] Here, in the rotating shaft rod 21, it is preferred to have a structure capable of adjusting the installation height H of the chain 22 installed on its side. In the crushing process, it is not only necessary to finely crush the roasted material of the waste battery, but also to be able to separate the valuable metals that are the object of recycling and other impurities that are not the object of recycling as clearly as possible, which is important in terms of efficiency. For example, when the crushing intensity is too strong and the degree of crushing becomes too fine, impurities may be distributed in large quantities to the undersize obtained in the processing of the screening process S3 of the next process. On the other hand, when the crushing intensity is too weak, the valuable metals will be mixed into the crushed material transferred to the oversize material, so that the recovery rate of the valuable metals may be reduced.

[0058] The degree of crushing depends on crushing time, crushing energy, etc., but by adjusting the installation height H of the chain 22 from the bottom surface 1F of the crushing container 1, that is, the chain height, the size of the crushed object, the crushed shape, etc. can be controlled with high precision to perform crushing processing. Then, by doing so, the recovery rate of valuable metals can be improved.

[0059] The structure capable of adjusting the installation height H of the chain 22 in the rotating shaft rod 21 is not particularly limited as long as the position of the installed chain 22 can be adjusted up and down in the height direction. Specifically, for example, a movable groove can be provided on the side of the rotating shaft rod 21 so that the installation height can be adjusted automatically or manually.

[0060] In the rotating shaft rod 21, the mounting height H of the chain 22 is not particularly limited, but is preferably in the range of 5 mm to 300 mm, more preferably in the range of 8 mm to 200 mm, and particularly preferably in the range of 10 mm to 100 mm. By mounting the chain 22 while adjusting the mounting height H within such a range, the degree of crushing can be more appropriately controlled to perform crushing processing.

[0061] Chain

[0062] As described above, the chain 22 is mounted on the side of the rotating shaft rod 21, and rotates by the rotation of the rotating shaft rod 21, so that the roasted object to be crushed collides with the chain 22 and is crushed. The chain 22 is a structure in which metal rings are connected to a predetermined length (see Figure 2 Schematic diagram of ).

[0063] In the chain mill device 2, the number of chains 22 mounted on the rotating shaft rod 21 is not particularly limited, but it is preferred that two or more chains 22 are mounted in the rotation direction. Specifically, when two or more chains are mounted in the rotation direction, mounting positions for the chains 22 are provided at two or more positions specified in the rotation direction of the side surface of the rotating shaft rod 21, and the chains 22 are independently mounted at the mounting positions. In this way, by mounting two or more chains 22 on the rotating shaft rod 21 for crushing, the crushing strength can be improved, and the valuable metals contained in the roasted product can be easily converted into powdered crushed products, thereby enabling more efficient recovery of the valuable metals.

[0064] In addition, the number of the chains 22 attached to the axial direction of the rotating shaft rod 21 may be one or may be two or more.

[0065] As described above, the rotating shaft rod 21 preferably has a structure capable of adjusting the installation height H of the chain 22 installed on the side thereof. Therefore, the chain 22 installed on the side thereof can adjust the installation height H (the height from the bottom surface 1F of the crushing container 1 to the installation position of the chain 22). By making the chain mill device 2 having such a structure, it is possible to more clearly separate the valuable metals to be recovered and other impurities that are not to be recovered, so that the valuable metals can be recovered more efficiently.

[0066] [Screening process]

[0067] In the screening step S3, the crushed material obtained by the crushing process in the crushing step S2 is screened and separated into the oversize and undersize using a sieve (screening machine) with a predetermined mesh size. In particular, in the case of waste batteries, the positive electrode active material containing a large amount of valuable metals is powdered by crushing and distributed under the sieve. Therefore, by screening and separating into the undersize and oversize, valuable metals can be effectively recovered.

[0068] Furthermore, in the valuable metal recovery method of the present embodiment, since the chain mill is used to perform the crushing process in the crushing step S2 of the previous step, a powder containing a large amount of valuable metals can be effectively obtained. Then, in the screening step S3, by screening the obtained crushed material into undersize and oversize, it becomes easy to separate the powder containing a large amount of valuable metals from other impurities that are not to be recovered, so that valuable metals can be effectively recovered from the undersize.

[0069] There is no particular limitation on the screening process, and a commercially available screening machine can be used for the screening process. In addition, the sieve hole diameter (sieve hole diameter of the screen) of the sieve can be appropriately set based on the conditions for screening the screened material and the screened material. In addition, when the sieve hole diameter of the sieve is too large, non-valuable metals under the sieve can be recovered in large quantities together with the valuable metals, so it is not preferred. In addition, when the sieve hole diameter of the sieve is too small, a large amount of valuable metals can be contained on the sieve, so it is not preferred. For example, when the sieve hole diameter of the sieve is less than 5mm, valuable metals can be effectively recovered, so it is preferred.

[0070] The screening machine is preferably placed in a closed space to prevent the crushed material from scattering around. By supplying the crushed material to the screening machine in a closed state, the scattering of powdered material and the loss of valuable metal recovery associated therewith can be more effectively prevented, and this is also preferred from the perspective of safety and operating environment.

[0071] [Oxidation roasting process]

[0072] Next, in the oxidation roasting step S4, the screened product obtained in the screening step S3 is roasted in an oxidizing atmosphere. The roasting treatment in the oxidation roasting step S4 can oxidize and remove the carbon component (carbon) contained in the screened product. Specifically, the carbon content in the obtained oxidation roasted product is made to be almost 0 mass %.

[0073] In this way, carbon can be removed by roasting in an oxidizing environment, and as a result, the molten microparticles of the reduced valuable metals generated locally in the reduction melting step S5 of the next step can be agglomerated without being physically hindered by carbon, and can be recovered as an integrated alloy. In addition, in the reduction melting step S5, phosphorus contained in the contents of the battery can be suppressed from being reduced by carbon, so that phosphorus can be effectively oxidized and removed, and its distribution into the alloy of the valuable metal can be suppressed.

[0074] In the oxidation roasting step S4, the oxidation roasting is performed at a temperature (oxidation roasting temperature) of 600° C. or more, for example. By setting the roasting temperature to 600° C. or more, the carbon contained in the battery can be effectively oxidized and removed. In addition, by preferably setting the temperature to 700° C. or more, the processing time can also be shortened. In addition, the upper limit of the oxidation roasting temperature is preferably 900° C. or less, thereby suppressing the thermal energy cost and improving the processing efficiency.

[0075] The treatment of oxidation roasting can be carried out using a known roasting furnace. In addition, in the reduction melting step S5 of the next step, a furnace (preparatory furnace) different from the melting furnace used in the melting treatment is set, and it is preferably carried out in this preparatory furnace. As a roasting furnace, any form of kiln that can heat the crushed material by supplying oxygen while performing oxidation treatment (roasting) inside it can be used. As an example, a known rotary kiln, a tunnel kiln (hearth furnace (hearth furnace)) etc. can be preferably used.

[0076] [Reduction melting process]

[0077] In the reduction melting step S5, the oxidized roasted product obtained by the roasting treatment in the oxidizing roasting step S4 is reduced and melted to obtain an impure slag and an alloy (metal) containing a valuable metal. In the reduction melting step S5, the oxide of the impurity element obtained by oxidation in the oxidizing roasting treatment is kept in its original state, and the oxide of the valuable metal oxidized in the oxidizing roasting treatment is reduced and melted, so that an alloy separated from the impurities and integrated with the reduced product can be obtained. In addition, the alloy obtained as a melt is also referred to as a "molten alloy".

[0078] In the reduction melting step S5, for example, the treatment can be carried out in the presence of carbon. Carbon is a reducing agent that has the ability to easily reduce nickel, cobalt, etc., which are valuable metals to be recovered. For example, graphite, etc., can be cited, which can reduce 2 moles of oxides of valuable metals such as nickel oxides with 1 mole of carbon. In addition, hydrocarbons, etc., which can reduce 2 to 4 moles per 1 mole of carbon, can be used as a carbon supply source. In this way, by carrying out reduction melting in the presence of carbon as a reducing agent, it is possible to effectively reduce the valuable metals and effectively obtain an alloy containing the valuable metals.

[0079] As carbon, except artificial graphite and natural graphite, coal, coke, etc. can be used as long as the impurities are tolerable in the product or in the subsequent process. In addition, preferably, the amount of carbon present is appropriately adjusted during the reduction melting treatment. Specifically, it is preferred to melt in the presence of carbon in a ratio of more than 7.5% by mass and less than 10% by mass, more preferably in a ratio of more than 8.0% by mass and less than 9.0% by mass, relative to 100% by mass of the oxidized roasted product as the treatment object.

[0080] The temperature condition (melting temperature) in the reduction melting treatment is not particularly limited, but is preferably in the range of 1320°C to 1600°C, and more preferably in the range of 1450°C to 1550°C. In addition, an oxide-based flux may be added to the reduction melting treatment. In addition, dust and exhaust gas may be generated in the reduction melting treatment, but these may be rendered harmless by performing conventionally known exhaust gas treatment.

[0081] Example

[0082] Hereinafter, the present invention will be described in more detail using Examples and Comparative Examples, but the present invention is not limited to the following Examples.

[0083] [Examples, Comparative Examples]

[0084] (Baking process)

[0085] As waste batteries, used lithium-ion batteries for vehicles with a rectangular outer shape were prepared and calcined at 920° C. for 6 hours in an atmospheric environment.

[0086] (Crushing process)

[0087] Next, in the crushing step, the calcined product obtained from the calcining step is placed in a crushing container in batches of 10 kg and crushed using a chain mill as a crusher (see Figure 2 Schematic diagram of the invention). Specifically, in Examples 1 to 10, the crushing conditions shown in Table 1 below were used. In Examples 8 to 10, the number of chain installation locations was 4, and two chains were installed at each of two installation height positions to perform the crushing process.

[0088] On the other hand, in Comparative Example 1, a double-shaft crusher was used as a crusher to perform the crushing process.

[0089] In each of the Examples and Comparative Examples, the crushed material obtained by the crushing was recovered and directly supplied to a screening machine used in the screening treatment in the next step.

[0090] (Screening process)

[0091] Next, in the screening step, one batch of crushed products recovered from the crusher was weighed and screened using a screening machine using a metal (stainless steel) plate having many holes with a diameter of 2.0 mm as a screen.

[0092] The above-mentioned screening treatment separates the recovered materials into powdery undersize and massive oversize and recovers them separately. The contents of nickel and cobalt are analyzed using a commercially available ICP emission spectrometer to determine the distribution of nickel and cobalt in the undersize and oversize.

[0093] [result]

[0094] Table 1 below shows the measurement results of the distribution ratios of nickel and cobalt based on the analysis values ​​of the contents of nickel and cobalt in the undersize and oversize materials in Examples 1 to 10 and Comparative Example 1.

[0095] [Table 1]

[0096]

[0097] As shown in Table 1, in Examples 1 to 10 in which a chain mill was used for crushing treatment, it can be seen that nickel and cobalt, which are valuable metals, are distributed in large quantities in the undersize, thereby enabling effective screening. In addition, in the chain mill device, since the distribution rate of nickel and cobalt varies depending on the position of the chain installation height H, it can be seen that the crushing can be controlled by the chain installation height H. In particular, it can be seen that when the chain installation height H is 50 mm and 90 mm, the distribution rate of nickel and cobalt can be improved, and valuable metals can be effectively recovered.

[0098] On the other hand, in Comparative Example 1, the distribution ratios of nickel and cobalt in the undersize were lower than those in the Examples.

[0099] Description of reference numerals:

[0100] 1 Broken container

[0101] 1F Bottom (bottom inside the crushing container)

[0102] 11 Sample input port

[0103] 12 Sample recovery port

[0104] 13 Gas supply and exhaust pipes

[0105] 2 Chain grinding device

[0106] 21 Rotating shaft rod

[0107] 22 Chain

Claims

1. A valuable metal recovery method for recovering valuable metals from waste batteries, wherein: The valuable metal recovery method has the following characteristics: Roasting process, roasting waste batteries; A crushing process in which the roasted material is loaded into a crushing container and crushed using a chain mill; and Screening process, screening the crushed material and separating it into oversize and undersize, The chain mill used in the crushing process in the crushing step has: A rotating shaft rod is vertically disposed relative to the bottom surface of the crushing container; and Chain, mounted on the side of the rotating shaft rod, In the chain mill, the chain is installed at an installation position at a distance from the bottom surface of the crushing container within a range of 8 mm to 200 mm, and the number of chain installation positions is 4, with two chains provided in each of two installation height positions.

2. The method for recovering valuable metals from waste batteries according to claim 1, wherein: The chain grinder has a structure capable of adjusting the installation height of the chain in the rotating shaft rod.

3. The method for recovering valuable metals from waste batteries according to claim 1 or 2, wherein: The valuable metal recovery method further comprises: an oxidative roasting step of oxidatively roasting the undersize material; and The reduction melting step is to reduce and melt the oxidized roasted product to obtain slag and an alloy containing valuable metals.

4. The method for recovering valuable metals from waste batteries according to claim 1 or 2, wherein: The valuable metal includes at least one selected from the group consisting of cobalt, nickel, and copper.

5. The method for recovering valuable metals from waste batteries according to claim 3, wherein: The valuable metal includes at least one selected from the group consisting of cobalt, nickel, and copper.

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