JP2021161526A - Valuable metal recovery method - Google Patents

Abstract

To provide a method for effectively recovering valuable metals when recovering valuable metals contained in a battery.SOLUTION: A method for recovering valuable metals from a waste battery includes: a roasting step S1 of roasting the waste battery to obtain a roasted product; a crushing step S2 of crushing the roasted product to obtain a crushed product; a sieving step S4 of sieving the crushed product into oversize materials and undersize materials; a wind sorting step S5 of sorting the oversize materials into heavyweight and lightweight materials by wind power; and a gas injection step S6 of injecting gas toward the oversize materials obtained in the sieving step. The lightweight materials obtained in the wind sorting step S5 are recovered, and the powdery oversize materials obtained in the gas injection step S6 are recovered together with the undersize materials obtained in the sieving step.SELECTED DRAWING: Figure 1

Description

The present invention relates to a method for recovering valuable metals contained in a waste battery.

In recent years, lithium-ion batteries have become widespread as secondary batteries that are lightweight and can obtain high output. As a basic structure of a lithium ion battery, there are 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.

A negative electrode active material such as graphite is fixed to the surface of the negative electrode current collector to form a negative electrode material. Further, a positive electrode active material such as lithium nickel oxide or lithium cobalt oxide is fixed to the surface of the positive electrode current collector to form a positive electrode material. The negative electrode material and the positive electrode material are charged into the above-mentioned outer can through a separator made of a polypropylene porous resin film or the like, and an electrolyte such as _{lithium hexafluorophosphate (LiPF 6) is contained in the gap between the negative electrode material and the positive electrode material.} An electrolytic solution or the like is sealed.

Lithium-ion batteries are currently being used as in-vehicle batteries for hybrid vehicles, electric vehicles, and the like. However, the lithium-ion battery mounted on an automobile gradually deteriorates as it is used repeatedly, and finally reaches the end of its life and is discarded.

As the power of automobiles changes from gasoline to electricity, the number of batteries used for automobiles will increase, and at the same time, the number of batteries that will be discarded will also increase.

Attempts and specific proposals for reusing such discarded lithium-ion batteries and defective products (hereinafter collectively referred to as "waste batteries") generated during the manufacture of lithium-ion batteries as resources have been conventionally made. Many are done. Most of them are pyrometallurgical processes in which waste lithium-ion batteries are put into a high-temperature furnace to melt the entire amount.

Here, in the waste battery of a lithium ion battery, in addition to commercially valuable elements such as nickel, cobalt, and copper (hereinafter, these are referred to as "valuable metals"), carbon, aluminum, and fluorine are used. , Phosphorus and other elements that are not commercially recoverable (hereinafter collectively referred to as "impurities") are contained. When recovering valuable metals from waste batteries, it is necessary to efficiently separate the above-mentioned impurities from the valuable metals.

Since the waste batteries of nickel-metal hydride batteries also contain valuable metals such as nickel and cobalt and impurities that cannot be recovered, they are also treated in the same manner.

For this reason, for example, a waste battery is roasted to perform a detoxification treatment for removing fluorine, phosphorus, etc. (roasting step), then crushed or crushed (crushing step), and then a smelter or a magnetic separator is used. The above-mentioned dry smelting process (hereinafter, also simply referred to as “dry treatment”) or the wet smelting process (hereinafter, simply “wet treatment”) in which the separated product is separated by using a liquid such as an acid or an organic solvent. ”) Is used to recover valuable metals.

As a method for recovering cobalt, which is a valuable metal from a waste battery by a dry treatment, for example, Patent Document 1 proposes a process in which a waste lithium ion battery is put into a melting furnace and oxygen is blown into it to oxidize it.

Further, Patent Document 2 proposes a process in which a waste lithium ion battery is melted, slag is separated to recover valuable resources, and then a lime-based solvent (flux) is added to remove phosphorus.

Further, in Patent Document 3, as a method of recycling a battery pack having a resin component including an assembled battery formed by connecting a plurality of cells in series and a control unit for controlling the assembled battery, a charged assembled battery It has a step of roasting the battery pack containing the battery pack as it is and a complete burning step of completely burning the unburned thermal decomposition gas generated at the time of roasting the battery pack. Disclosed is a recycling method in which the assembled battery in the battery pack is roasted in a non-oxidizing atmosphere or a reducing atmosphere at a temperature equal to or higher than the carbonization temperature of the resin forming the resin part and lower than the melting point of the metal part of the battery pack. There is.

Japanese Unexamined Patent Publication No. 2013-091826 Japanese Patent Application Laid-Open No. 2013-506048 Japanese Unexamined Patent Publication No. 2010-3512

By the way, in the recovery method for recovering valuable metals from waste batteries, the crushed products obtained through the roasting step and the crushing step include powder containing a large amount of valuable metals such as those derived from the positive electrode active material, and waste batteries. It is composed of a mixture of a mass containing a large amount of impurities derived from electrodes, cans, screws, etc. Therefore, the crushed material obtained is sieved to separate the agglomerates, and the powder obtained as the undersief is used as a processing target for dry treatment, and the valuable metal is recovered.

However, the mass obtained as a sieve product contains a thin film containing copper derived from an electrode (negative electrode) and a powder containing a valuable metal derived from a positive electrode active material, and when the sieve product is treated as waste. It will be a loss of recovery of valuable metals. It is preferable to recover the valuable metal contained in such a lump from the viewpoint of improving the yield.

The present invention has been proposed in view of such circumstances, and an object of the present invention is to provide a method for effectively recovering valuable metals contained in a waste battery.

The present inventor has made extensive studies to solve the above-mentioned problems. As a result, the roasted product obtained by roasting the waste battery is crushed to a predetermined size, and then the sieving product obtained by sieving the crushed product is subjected to a wind sorting process to recover the lightweight product, and further gas is released. We have found that the above problems can be solved by recovering the powder sieve obtained by spraying, and have completed the present invention.

(1) The first aspect of the present invention is a valuable metal recovery method for recovering valuable metals from a waste battery, which is a roasting step of roasting the waste battery to obtain a roasted product and crushing the roasted product. A crushing step for obtaining a product, a sieving step for sieving the crushed product into a sieving product and a sieving product, a wind selection step for wind-sorting the sieving product into a heavy product and a lightweight product, and the weight. It has a gas injection step of injecting gas toward an object, a lightweight substance obtained in the wind selection step is recovered, and a powdery sieved product obtained in the gas injection step is subjected to the sieving step. This is a valuable metal recovery method for recovering together with the sieve product obtained in.

(2) The second aspect of the present invention further includes, in the first invention, a magnetic separation step of separating the magnetically deposited material by magnetically separating the crushed material obtained in the crushing step, which was obtained in the magnetic separation step. This is a valuable metal recovery method in which a non-magnetized material is subjected to the sieving step.

(3) The third aspect of the present invention is the oxidative roasting step of obtaining the oxidative roasted product by oxidatively roasting the recovered sieving product and the powdered sieving product in the first or second invention. This is a valuable metal recovery method further comprising a reduction melting step of reducing and melting the oxidized roasted product to obtain a slag and an alloy containing a valuable metal.

(4) A fourth aspect of the present invention is that in any one of the first to third inventions, in the gas injection step, a valuable metal that injects an inert gas toward the sieved product obtained in the sieving step. It is a collection method.

(5) Fifth of the present invention, in any one of the first to fourth inventions, the amount of gas injected in the gas injection step is 1.0 L / (minutes) with respect to 1.0 kg of the sieve product. -Kg) or more and 80 L / (minutes-kg) or less is a valuable metal recovery method.

(6) In the sixth aspect of the present invention, in any one of the first to fifth inventions, the valuable metal contained in the waste battery is a valuable metal recovery containing at least one selected from cobalt, nickel, and copper. The method.

According to the present invention, it is possible to provide a method for effectively recovering valuable metals in a method for recovering valuable metals contained in a waste battery.

It is a process drawing which shows an example of the flow of a valuable metal recovery method.

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 embodiments, and various modifications can be made without changing the gist of the present invention.

≪1. Overview of valuable metal recovery method ≫
The valuable metal recovery method according to the present embodiment is a method of recovering valuable metal from a waste battery. Generally, when recovering a valuable metal from a waste battery, a wet treatment may be performed in addition to the dry treatment, but the valuable metal recovery method according to the present embodiment is mainly related to the dry treatment.

Specifically, this valuable metal recovery method is applied to a sieved product obtained by roasting a waste battery for detoxification, crushing the roasted product to a predetermined size, and then sieving the crushed product. It is characterized in that a lightweight material is recovered by subjecting it to a wind sorting process, and then a gas is blown to recover the powdered sieve product together with the sieve product obtained in the sieving step.

According to such a method, the valuable metal can be effectively recovered from the waste battery by separating the lightweight material containing the valuable metal from the sieve product and the powder sieve product. Further, unlike the prior art, separate treatments such as dehydration and drying, and a large amount of equipment and maintenance are not required, so that valuable metals can be recovered by inexpensive treatments.

Here, as described above, the waste battery is a defective product or a manufacturing process generated in the manufacturing process of a used secondary battery such as a lithium ion battery or a nickel hydrogen battery, or a positive electrode material constituting the secondary battery. It is a concept that includes waste materials in the battery manufacturing process such as internal residues and generated waste. As described above, such waste batteries contain valuable metals such as nickel, cobalt, and copper that have economic value to be recovered and reused.

≪2. About each process of valuable metal recovery method ≫
FIG. 1 is a process diagram showing an example of the flow of the valuable metal recovery method according to the present embodiment. In this valuable metal recovery method, a roasting step S1 for roasting a waste battery to obtain a roasted product, a crushing step S2 for crushing the roasted product to obtain a crushed product, and a magnetic selection of the crushed material to separate the magnetic material. Magnetic sorting step S3 for sieving, sieving step S4 for sieving crushed material (non-magnetized material) into sieving material and sieving material, and wind force for heavy material and lightweight material with respect to the obtained sieving material. It has a wind selection step S5 for sorting and a gas injection step S6 for injecting gas toward a heavy object. Here, valuable metals such as nickel and cobalt are metals contained in the positive electrode active material and are recovered in powder form, so that they are largely distributed to the sieve.

Further, the oxidative roasting step S7 in which the recovered product obtained in the above step is oxidatively roasted, and the reduction melting of the oxidative roasted product to obtain slag and an alloy (metal) containing a valuable metal. It further comprises step S8.

The valuable metal alloy obtained through such a series of dry treatments is subjected to wet treatments such as neutralization treatment, solvent extraction treatment, and electrowinning to remove impurity components remaining in the alloy. Valuable metals can be further refined and recovered as high value-added metals.

[Roasting process]
The main purpose of the roasting step S1 is to remove the fluorine component, which is an electrolytic solution component contained in the waste battery, to make it harmless, and to facilitate crushing in the next step.

The conditions for the roasting treatment are not particularly limited, but the roasting temperature is heated to 700 ° C. or higher from the viewpoint of ensuring detoxification and making the waste battery brittle and facilitating crushing in the next step. Is preferable. The upper limit of the roasting temperature is not particularly limited, but is preferably 1200 ° C. or lower. If the roasting temperature is too high, a part of iron, etc., which is mainly used for the outer shell of the waste battery, adheres to the inner wall of the roasting furnace body such as a kiln, which hinders smooth operation. Or, it may lead to deterioration of the kiln itself, which is not preferable.

Further, if the waste batteries used for the roasting process are stacked too much in the furnace, the inside cannot be sufficiently roasted and uneven roasting occurs. Therefore, from the viewpoint of enabling uniform roasting, it is preferable to select the processing amount, the heating capacity of the roasting furnace, and the like. For example, it is preferable to perform a preliminary test in advance to determine the optimum temperature and roasting time.

The heating method at the time of roasting is not particularly limited, and may be an electric type or a burner type using a fuel such as oil or gas. In particular, burner-type heating is preferable because of its low cost.

[Crushing process]
In the crushing step S2, the roasted product obtained by roasting the waste battery in the roasting step S1 is crushed and finely separated.

The crushing device used in the crushing treatment is not particularly limited, and for example, a rod mill, a jaw crusher, a twin-screw kneader, a chain mill and the like can be used. Among them, the chain mill is preferable because it can efficiently crush the waste battery. Since there are various types and shapes of waste batteries, an appropriate crusher may be selected according to the purpose.

[Magnetic separation process]
In the magnetic separation step S3, the crushed material obtained in the crushing step S2 is subjected to a magnetic separation process to separate the magnetically deposited material. In addition, in the method for recovering valuable metals according to the present embodiment, it is not an essential aspect to include the magnetic separation step S3.

If the crushed material of the waste battery contains a magnetic material such as iron, it greatly affects the melting point and viscosity of the slag during the dry treatment, which complicates the slag design and makes operation management difficult. When recovering valuable metals from a waste battery containing a large amount of magnetic material such as, it is preferable to have a magnetic separation step.

The magnetic separator used in the magnetic separation process is not particularly limited, but for example, a hanging magnetic separator can be used.

[Sieve separation process]
In the sieving step S4, the obtained crushed product is sieved into a sieving product and a sieving product using a sieve having a predetermined opening.

The sieving process is not particularly limited and can be performed using a commercially available sieving machine. Further, the mesh opening of the sieve (opening of the screen) and the like can be appropriately set based on the conditions for separating the upper and lower sieve products.

The opening of the sieve may be determined according to the type and shape of the waste battery to be crushed. If the opening is too large, a large amount of non-valuable metal as well as valuable metal will be recovered under the sieve, which is not preferable. Further, if the opening is too small, a large amount of valuable metal is contained on the sieve, which is not preferable. Generally, it is preferable that the opening is 5 mm or less because valuable metals can be efficiently recovered.

The sieved product (powder) recovered in this way can be treated in the oxidation roasting step S7 and the reduction melting step S8 together with the powdered sieve product obtained in the gas injection step S6 described later to recover the valuable metal. .. Further, after that, a known wet treatment can be performed to recover the valuable metal having high purity.

Although it is not an essential aspect, when it is subjected to the next step, it may be subjected to a step (second magnetic separation step) in which the sieved product obtained in the sieving step S4 is subjected to a magnetic separation treatment. The magnetic substance such as iron contained in the crushed product of the waste battery is not contained in the sieve product, and even if it is present, the amount is negligible. Instead of being subjected to the magnetic separation step S3 of the above, the sieved product obtained in the sieving step S4 may be subjected to the second magnetic separation step. Further, the crushed product obtained in the crushing step S2 is subjected to a magnetic separation step (first magnetic separation step) S3, and the sieved product obtained in the sieving step S4 is further subjected to a magnetic separation process (second magnetic separation step). You may provide it.

[Wind selection process]
In the wind selection step S5, the sieved product obtained in the sieving step S4 is wind-sorted into a heavy product and a lightweight product. Especially in the case of waste batteries, the copper derived from the electrode (negative electrode) is a thin film and is often distributed on the sieve without being pulverized, which causes a recovery loss of copper, which is a valuable metal. ..

In this respect, according to the method according to the present embodiment, the sieving material obtained in the sieving step is subjected to a wind sorting process, whereby the lightweight material contained in the sieving material is recovered. As a result, the recovery loss of copper derived from the electrode (negative electrode) can be effectively suppressed.

The wind power sorting process is a process of sorting things having different shapes, specific densities, volumes, etc. using wind power. Since the copper derived from the electrode (negative electrode) contained in the sieve material has a thin film shape, it is possible to recover the copper derived from the electrode (negative electrode) as a lightweight material by performing a wind sorting process.

The speed of supplying wind power to the sieve is not particularly limited, but it is preferably 10 L / min or more and 60 L / min or less. By setting the content to 10 L / min or more, a large amount of copper can be recovered from the sieve. By setting the value to 60 L / min or less, the loss of valuable metal can be reduced.

Copper can be obtained from the recovered lightweight material by using a conventionally known copper smelting method. For example, the recovered lightweight material is subjected to a dry process of melting at a high temperature to separate components other than copper as slag, etc., and the blister copper obtained in the dry process is subjected to a wet process such as electrolytic refining. Therefore, high-purity copper can be obtained.

Further, as will be described later, it may be subjected to an oxidative roasting step together with the sieved product obtained in the sieving step.

The wind sorter for performing the wind sort process is not particularly limited, but for example, a circulating wind sorter can be used.

[Gas injection process]
In the gas injection step S6, a powdery substance (powdered sieve substance) adhering to the sieve substance is obtained by injecting gas toward the heavy substance (sieving substance) obtained in the wind selection step S4. Especially in the case of waste batteries, the positive electrode active material containing a large amount of valuable metal is crushed into powder and distributed under the sieve, but in reality, it often adheres to a lump and is distributed on the sieve. Causes a loss in recovery of valuable metals.

In this respect, according to the method according to the present embodiment, the gas is sprayed onto a heavy object (sieving object), whereby the powdery substance (powdered sieve substance) adhering to the sieve substance is sprayed. The recovery loss of valuable metals can be effectively suppressed by recovering the powder and subjecting it to the dry treatment.

Further, in the valuable metal recovery method according to the present embodiment, since the wind selection step S5 is provided as a pre-step of the gas injection step S6, the thin film-shaped copper is hardly contained. Therefore, the injection of gas is not blocked by the thin-film copper, and the powdery substance (powdered sieve substance) adhering to the sieve substance can be separated more effectively.

An inert gas such as nitrogen or argon can be used as the gas to be sprayed on the sieve. In addition, air can also be used when there is no danger of heat generation or dust explosion on the sieve. In addition, a commercially available gas blowing device can be used for spraying the gas.

The flow rate of the gas is not particularly limited, but is preferably 1.0 L / (minutes / kg) or more and 80 L / (minutes / kg) or less per 1.0 kg of the sieve product. By setting the content to 1.0 L / (minutes / kg) or more, a large amount of valuable metal can be recovered from the mass obtained as a sieve. By setting the content to 80 L / (minute / kg) or less, the loss of the powdery sieve material can be reduced.

In particular, in the valuable metal recovery method according to the present embodiment, since the wind selection step S5 is provided as a pre-step of the gas injection step S6, the thin-film copper does not block the gas injection, and comparison is made. The powdery substance (powdered sieve substance) adhering to the sieve substance can be effectively recovered even at a small flow rate.

Further, the gas may be blown to the sieved object from a single gas blowing port, but it is preferable to provide two or more gas blowing ports and blow the gas from a plurality of places. In this way, by spraying the gas through two or more gas outlets, it is possible to spray the gas evenly on the sieved material, and the powdery valuable metal can be separated more efficiently from the lumpy material. Can be advanced.

Here, it is preferable that the gas blowing device for performing gas blowing is placed in a closed space and has a structure in which the sieve material does not scatter to the surroundings. By spraying gas onto the sieved material in a sealed state and sieving it in this way, the separation efficiency of valuable metals can be improved, and the scattering of powder can be effectively prevented, which is safe. It is also preferable from the viewpoint of surface and recovery rate.

[Oxidation roasting process]
In the oxidative roasting step S7, the recovered product obtained in the above step is roasted in an oxidative atmosphere. Specifically, the powdery sieving product obtained in the gas injection step S6 is recovered as a recovered product together with the sieving product obtained in the sieving step S4, and the recovered product is roasted in an oxidizing atmosphere. In this way, by recovering the powdery sieve product to be treated as waste and subjecting it to the oxidation roasting step S6, it is possible to reduce the recovery loss of valuable metals.

The recovered material may include a lightweight material recovered in the wind selection step S5. This lightweight material is mainly copper derived from an electrode (negative electrode), and copper can be recovered as a valuable metal together with nickel and cobalt.

Then, by the roasting treatment in the oxidation roasting step S6, the carbon component (carbon) contained in the sieved product or the powdered sieve product can be oxidized and removed. Specifically, the carbon content in the obtained oxidized roasted product is set to approximately 0% by mass.

In this way, carbon can be removed by roasting in an oxidizing atmosphere, and as a result, the molten fine particles of the reducing valuable metal locally generated in the reduction melting step S8 of the next step are physically damaged by carbon. It is possible to agglomerate without any, and it can be recovered as an integrated alloy. Further, in the reduction melting step S8, it is possible to suppress the reduction of phosphorus contained in the contents of the battery by carbon, effectively oxidatively remove the phosphorus, and suppress the distribution in the alloy of the valuable metal.

In the oxidative roasting step S7, oxidative roasting is performed at, for example, a temperature of 600 ° C. or higher (oxidative roasting temperature). By setting the roasting temperature to 600 ° C. or higher, carbon contained in the battery can be effectively oxidized and removed. Further, the processing time can be shortened by preferably setting the temperature to 700 ° C. or higher. Further, the upper limit of the oxidative roasting temperature is preferably 900 ° C. or lower, whereby the thermal energy cost can be suppressed and the processing efficiency can be improved.

The oxidative roasting process can be performed using a known roasting furnace. Further, it is preferable to provide a furnace (preliminary furnace) different from the melting furnace used in the melting process in the reduction melting step S7 of the next step, and perform the process in the preliminary furnace. As the roasting furnace, any type of kiln that can be oxidized (roasted) inside by heating the crushed material while supplying oxygen can be used. As an example, a known rotary kiln, tunnel kiln (Haas furnace) or the like can be preferably used.

Further, in the process of oxidative roasting, an oxidant may be introduced into the furnace in order to adjust the degree of oxidation. The oxidizing agent is not particularly limited, but it is preferable to use a gas containing oxygen such as air, pure oxygen, and oxygen-enriched gas from the viewpoint of easy handling. The amount of the oxidizing agent introduced can be, for example, about 1.2 times the chemical equivalent required for the oxidation of each substance to be oxidized.

[Reduction melting process]
In the reduction melting step S8, the oxidative roasted product obtained by the roasting treatment in the oxidation roasting step S6 is reduced and melted to obtain a slag containing impurities and an alloy (metal) containing a valuable metal. In the reduction and melting step S8, the oxides of the impurity elements obtained by oxidation in the oxidation roasting treatment are left as they are, and the oxides of the valuable metals that have been oxidized in the oxidation roasting treatment are reduced and melted. As a result, it is possible to obtain an alloy that is separated from impurities and has a reduced product integrated. The alloy obtained as a melt is also referred to as "fused gold".

In the reduction melting step S8, for example, the treatment can be performed in the presence of carbon. The carbon is a reducing agent capable of easily reducing the valuable metals such as nickel and cobalt to be recovered. For example, 1 mol of carbon can reduce 2 mol of an oxide of a valuable metal such as nickel oxide. Examples include graphite. Further, a hydrocarbon or the like capable of reducing 2 to 4 mol per 1 mol of carbon can also be used as a carbon supply source. As described above, by reducing and melting in the presence of carbon as a reducing agent, the valuable metal can be efficiently reduced and an alloy containing the valuable metal can be effectively obtained.

As carbon, in addition to artificial graphite and natural graphite, coal, coke and the like can be used as long as impurities are acceptable in the product and post-processes. Further, in the reduction melting treatment, it is desirable to appropriately adjust the abundance of carbon. Specifically, preferably, the ratio is more than 7.5% by mass and 10% by mass or less with respect to 100% by mass of the oxidized roasted product to be treated, and more preferably 8.0% by mass or more and 9.0% by mass or less. It melts in the presence of a proportion of carbon.

The temperature condition (melting temperature) in the reduction melting treatment is not particularly limited, but is preferably in the range of 1320 ° C. or higher and 1600 ° C. or lower, and more preferably in the range of 1450 ° C. or higher and 1550 ° C. or lower. Further, in the reduction melting treatment, an oxide-based flux may be added and used. In the reduction melting treatment, dust, exhaust gas, etc. may be generated, but it can be detoxified by performing a conventionally known exhaust gas treatment.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples.
[Examples, comparative examples]
(Roasting process)
As a waste battery, we prepared a used lithium-ion battery for automobiles with a square outer shape. This waste battery was roasted in an air atmosphere at a temperature of 920 ° C. for 6 hours.

(Crushing process)
The roasted product obtained by roasting was crushed at 12 kg / batch by a crusher using a chain mill for 30 seconds to obtain a crushed product.

(Magnetic separation process)
For the crushed material obtained by crushing, each sample was supplied to the magnetic separator at a supply speed of 5.0 kg / min by a magnetic separator using a suspended magnetic separator to obtain a non-magnetic material.

(Sieve separation process)
Next, the non-magnetic deposit (crushed product) obtained in the above magnetic separation step was subjected to a sieving step. A continuous vibrating sieve was used for sieving. The mesh size of the sieve was 3.0 mm, and the supply rate of the sample (non-magnetic material) was 2.0 kg / min. As a result, the crushed product was sieved into a sieve product and a sieve product.

(Wind selection process)
The sieved product obtained in the sieving step was wind-sorted into a heavy product and a lightweight product. Specifically, wind power was supplied to the sieved product obtained in the sieving step by a commercially available continuous wind separator. At this time, the wind power supply speed was controlled to 30 L / min.

(Gas injection process)
By injecting gas toward a heavy product (sieving product) obtained in the wind selection step, a powdered sieving product contained in the sieving product was obtained. Specifically, 10 kg of a heavy substance obtained in the wind selection step was supplied per batch (1 example), and nitrogen gas (inert gas) was sprayed. The supply rate of the sieved product was 10.0 kg / min, and the gas supply flow rate was as shown in Table 1 below.

As described above, the obtained powdery sieve material was recovered, and the content of valuable metal components (copper, nickel, cobalt) was analyzed for each of them using a commercially available ICP emission spectrophotometer and recovered. The total amount of valuable metals and the total amount of recovered impurities (components other than copper, nickel, and cobalt) were calculated. The measurement results are shown in Table 1.

From Table 1, it can be seen that the powdery sieve product obtained by the gas injection step contains valuable metals. Therefore, it can be seen that by recovering the powdery sieve product and subjecting it to the oxidative roasting step together with the sieve product, the recovery loss of the valuable metal can be effectively suppressed and the valuable metal can be effectively recovered from the waste battery.

The lightweight material obtained in the wind selection step contained thin-film copper derived from the electrode (negative electrode). From this, it can be seen that copper can be effectively recovered by recovering the lightweight material obtained in the wind selection process as a recovered product.

Claims (6)

A valuable metal recovery method for recovering valuable metals from waste batteries.
The roasting process of roasting waste batteries to obtain roasted products,
A crushing step of crushing the roasted product to obtain a crushed product,
A sieving step of sieving the crushed product into a sieving product and a sieving product,
A wind selection process for wind-sorting the sieved product into a heavy product and a lightweight product,
A gas injection process that injects gas toward the heavy object, and
Have,
The lightweight material obtained in the wind selection process is collected and collected.
A valuable metal recovery method for recovering a powdery sieve product obtained in the gas injection step together with a sieve product obtained in the sieving step. It further has a magnetic separation step of separating the magnetically deposited material by magnetically separating the crushed material obtained in the crushing step.
The valuable metal recovery method according to claim 1, wherein the non-magnetized material obtained in the magnetic separation step is subjected to the sieving step. Oxidative roasting process to obtain oxidative roasted product by oxidative roasting of recovered material,
The valuable metal recovery method according to claim 1 or 2, further comprising a reduction melting step of reducing and melting the oxidized roasted product to obtain slag and an alloy containing a valuable metal. The valuable metal recovery method according to any one of claims 1 to 3, wherein in the gas injection step, an inert gas is injected toward the sieved product obtained in the sieving step. The amount of gas injected in the gas injection step is 1.0 L / (minutes / kg) or more and 80 L / (minutes / kg) or less with respect to 1.0 kg of the sieve product. The method for recovering valuable metals described in 1. The valuable metal recovery method according to any one of claims 1 to 5, wherein the valuable metal contained in the waste battery includes at least one selected from cobalt, nickel, and copper.

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