JPH1074539A - Method for recovering reusable material from used lithium battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To recover reusable material by one crushing by roasting used lithium batteries, crushing, and magnetically separating a magnetic material and a non-magnetic material. SOLUTION: Used lithium battery raw material 1 is roasted with a roasting furnace 3, crushed with a crushing machine 2 in to the dimensions suitable for magnetic separation. A magnetic material in the crushed materials is separated from a non-magnetic material with a magnetic separator 7, then they are separately sieved with a sieving machine 8. In the roasting of the raw material 1, an organic material is decomposed, burned, and vaporized to generate CO gas. In low temperature roasting, reduction of metallic lithium by CO gas is insufficient, load in rushing is made large, and in high temperature roasting, the raw material 1 is melted and coagulated to make crushing difficult. Roasting at 800-1000 deg.C is preferable. The magnetic material and the non-magnetic material are magnetically separated, the magnetic material is used as a heat resistant alloy material and the non-magnetic material is used as the raw material of copper. In the sieving machine 8, the magnetic material is separated into powdery cobalt and plate-shaped or block iron component, and the non-magnetic material is separated into foil-shaped copper and powdery aluminum. Reusable materials are recovered and load in crushing is lightened.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for recovering valuable resources from a used lithium battery. Lithium batteries are used as power sources for mobile phones, PHSs, video cameras, notebook computers, and the like because of their features such as small size, light weight, and high energy density per volume.

The main components of a lithium battery are a steel case, a negative electrode plate made of copper foil, a positive electrode plate made of aluminum foil coated with lithium metal oxide (metal = Mo, Co, Ni, etc.),
Examples include a separator made of polyethylene or the like. Since Mo, Co, Ni and the like contained in lithium metal oxide are valuable metals, some recovery methods have been proposed.

[0003]

2. Description of the Related Art According to Japanese Patent Application Laid-Open No. 6-322452, a crushed product of a used lithium secondary battery, which is separated by magnetic separation from magnetic materials such as metallic nickel, is roasted in a non-oxidizing atmosphere. Or reduction roasting in a reducing atmosphere and subjecting the resulting roasted product to magnetic separation have been proposed.
Roasting in a non-oxidizing atmosphere in the above method is a step for reducing the metal oxide by a carbonaceous substance contained as separator, carbon of the negative electrode material, etc.,
The last magnetic separation is a process for separating nickel and cobalt from copper and the like.

According to Japanese Patent Application Laid-Open No. 6-346160,
It has been proposed that a used lithium secondary battery is roasted to remove a binder, a solvent, and the like, and the roasted product is crushed and sieved to use the sieved material as a raw material for smelting.

[0005]

Problems to be Solved by the Invention JP-A-6-322, cited above.
In Japanese Patent No. 452, a used lithium secondary battery is directly crushed, but this crushing is more difficult than crushing of a roasted product. Further, in order to reduce the burden of roasting, since the crushed material is directly magnetically separated without roasting, magnetic separation for separating a non-magnetic material and a magnetic material is performed twice before and after roasting. next,
In the method disclosed in JP-A-6-346160, the recovery of Ni and Co is left to the smelting process, so there is room for improvement in terms of thermal energy.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to recover valuable metals from used lithium batteries by a method that facilitates pulverization and requires only one magnetic separation. It is characterized by baking, crushing the obtained roasted product, and magnetically separating it into a magnetic material and a non-magnetic material. Hereinafter, the method of the present invention will be described in detail.

First, in the method of the present invention, a spent lithium battery is roasted to obtain polypropylene,
Organic substances such as n-methyl-2-pyrrolidone are decomposed, burned and volatilized, and CO as a reducing gas is generated. If the roasting temperature is too low, the reduction of lithium metal oxide by the CO gas generated by decomposition of organic matter becomes insufficient and the burden of crushing increases, while if it is too high, the roasted material melts and solidifies and its crushing is difficult. 550 to 1100 ° C., more preferably 800 to 1000 ° C., because melting of copper occurs and the furnace is damaged.

[0008] The heating furnace for roasting is not limited,
It can be performed in a stationary furnace such as an electric furnace or a heavy oil furnace. In this case, a direct heating furnace under a stoker can be used. One batch of used lithium batteries is stacked on a stoker, and a flue of combustion exhaust gas is provided from the upper part of the furnace, and roasting is performed while appropriately discharging combustion gas. When the used lithium battery is roasted without being crushed, the above-described burning of organic substances and generation of CO gas occur inside the battery, and the reduction of oxide proceeds in the space in the battery case. This roasting reduces most of iron oxide, nickel oxide, cobalt oxide and the like, while copper foil and the like maintain a metal form. Aluminum is melted and thinly attached to any powder, lump or the like.
The obtained roasted product is about 70% for the used lithium battery.
Up to 90% by weight of metal powder, lump, net, foil, plate or these partially maintain the bonding structure in the battery. In addition to metals, some unburned carbon and organic substances are also included.

Next, the roasted material is crushed. This crushing has various forms as described above, and also prepares roasted products of various sizes to an appropriate size, and those that maintain the structure of the battery are separated into powder, plate, foil and other material forms. This operation facilitates separation into a magnetic substance and a magnetic substance in the magnetic separation. The crusher is not limited, but a single-shaft crusher or the like can be preferably used. The crushing is JIS
It is preferred to make the standard sieve of Z8801 less than 20 mm. In the crushing after roasting according to the method of the present invention, instead of directly crushing the battery itself, in order to crush the battery once crushed to some extent and reduced in weight by roasting,
The crushing burden is reduced. In addition, since the roasted product is almost entirely composed of metal and hardly contains carbon and organic substances that are difficult to crush, the burden of crushing is also reduced in this aspect.

In the last step of the present invention, magnetic separation is performed. This is a step for separating a roasted metal lithium salt and a roasted iron such as a case, which are magnetic substances, from non-magnetic substances. During the roasting, the aluminum foil supporting the metal lithium salt melted, so it was thought that an alloy of cobalt and aluminum might have been formed. It turned out that there was a lot of unity. Therefore, there is little aluminum in the magnetic material separated by magnetic separation. The magnetic material obtained as described above can be used as a raw material such as a heat-resistant alloy. The non-magnetic material can be a raw material for copper.

Further, if it is necessary to separate the Fe-rich component and the Co-rich component, a magnetic material, preferably JIS
When sieving with a standard sieve of Z8801 to 420 to less than 5000 μm or more, the upper part of the screen becomes iron scrap, and the lower part is separated as a cobalt raw material. Such a separation is possible because, in the crushed material after roasting, cobalt is generally in a powdery state, and iron is generally in a plate or lump. Similarly, when it is necessary to separate the Cu-rich portion and the Al-rich portion in the non-magnetic material, the non-magnetic material is preferably separated by JI.
When sieving with a standard sieve of SZ8801 to 420 to less than 5000 μm, the upper sieve becomes the former and the lower sieve becomes the latter. Such separation is possible because, in the crushed material after roasting, copper is generally in a foil shape and aluminum is generally in a granular shape. The above description regarding Co is exactly the same even if it is replaced with Ni. That is, since Ni is a magnetic substance, it can be recovered in the same manner as Co.

Hereinafter, the present invention will be described more specifically with reference to a flowchart for carrying out the present invention. A used lithium battery is used as a raw material 1, and 400 kg, for example, is charged into a roasting furnace 3 such as an electric furnace or a heavy oil furnace. When the roasted valuable metal content reaches several tons, the crusher 2 crushes it to a size suitable for magnetic separation. The crushed pieces are separated into a magnetic substance and a non-magnetic substance by a magnetic separator 7 having two conveyors and an electromagnet as elements. The magnetic substance and the non-magnetic substance are separated by the sieving machine 8 into upper and lower sieves. In addition, 3 is a dust collecting facility, 4 is a suction fan, 8 is a portable conveyor, 10 is a container bag above the sieve, and 11 is a container bag below the sieve. Hereinafter, the present invention will be described in more detail with reference to Examples.

[0013]

EXAMPLES The metal compositions of the raw materials were as follows.

[0014]

[Table 1]

When 10 tons of the raw material was roasted at 1000 ° C. for 1 hour, the weight was reduced by 2.2 tons, but the metal composition did not change. Next, magnetic separation is performed and the magnetic material is 6.0 ton.
n and 1.8 ton of nonmagnetic material were obtained. The respective compositions are as shown in Tables 2 and 3. (Below)

[0016]

[Table 2]

[0017]

[Table 3]

Subsequently, the magnetic material was sieved with a sieving machine (5 mesh) to obtain a sieve (3.2 ton) shown in Table 4 and a sieve (3.0 ton) shown in Table 5. (Below)

[0019]

[Table 4]

[0020]

[Table 5]

The non-magnetic material was similarly sieved with a sieving machine (5 mesh), and sieved on a sieve (1.4 ton) shown in Table 6 and Table 7
(0.4 ton) was obtained. (Below)

[0022]

[Table 6]

[0023]

[Table 7]

As described above, according to the present invention, Co
Can be recovered under the magnetic material sieve, and Fe can be recovered as the magnetic material on the sieve. In addition, copper-rich copper can be recovered as a nonmagnetic material on a sieve, and Al-rich copper can be recovered as a nonmagnetic material under a sieve.

[0025]

【The invention's effect】

(1) Valuables can be collected by one crushing of a used lithium battery. (2) Since the entire amount of the used lithium battery is not crushed, the burden of crushing is reduced. (3) Since the recovered cobalt content has a purity of 38% or more, it can be used as a cobalt raw material. Although a small amount of aluminum accompanies, it is easily removed by oxidation. (4) Since the recovered iron has high Fe purity, it can be used as any iron source. (5) Copper recovered as a non-magnetic material is used as a raw material for copper smelting in converters, flash smelting furnaces and the like. However, it is preferable to separate the mixture into a Cu-rich portion and an Al-rich portion. The former is preferably used as a raw material for a PS converter and the latter as a raw material for a flash smelting furnace in terms of smelting operation. (6) As described above, although the purity of the valuable metal is high in each recovered material, only one magnetic separation is required. (7) In summary, when the method of the present invention is carried out, running costs are low, and only one crusher and one magnetic separator are required, so that capital investment costs are low, and the recovered materials are very valuable. It is suitable for sale to manufacturers and non-ferrous smelters.

[Brief description of the drawings]

FIG. 1 is a flow sheet of a method for carrying out the method of the present invention.

[Explanation of symbols]

 Reference Signs List 1 raw material 3 roasting furnace 5 crusher 7 magnetic separator

Claims (3)

[Claims] 1. A method for recovering valuable resources from a used lithium battery, comprising roasting a used lithium battery, crushing the obtained roasted product, and magnetically separating the obtained product from a magnetic material and a non-magnetic material. . 2. The used lithium battery according to claim 1, wherein the magnetic material separated by the magnetic separation is sieved to be separated into an upper sieve mainly composed of iron chips and a lower sieve mainly composed of cobalt. Valuable resources recovery method. 3. The valuable lithium battery according to claim 1, wherein the non-magnetic material separated by the magnetic separation is sieved to be separated into an aluminum-rich sieve and a copper-rich sieve. Object collection method.