Method for homogenizing lithium battery black powder

Abstract

The present invention discloses a method for homogenizing lithium battery black powder, which comprises the following steps: putting the lithium battery black powder into a reaction tank with controllable temperature for cleaning; performing filtration with controllable temperature on the solid obtained from the cleaning; putting the obtained filter cake into a flotation cell, preparing the lithium battery black powder into a flotation ore pulp with water, adding a carbon capture agent and a foaming agent to the flotation ore pulp to obtain a carbon product and a metal salt sedimentary ore. If the carbon content in the metal salt sedimentary ore > 0.5 wt%, continue to put it into the flotation cell for flotation until the carbon content < 0.5 wt%; performing magnetic separation on the metal salt sedimentary ore with a carbon content < 0.5 wt% to remove the iron component contained therein; performing eddy current separation on the obtained product to remove the aluminum component contained therein; the obtained solid is a metal salt concentrate containing lithium, manganese, cobalt, and nickel components, and subsequent extraction of valuable metals and chemical refining treatment can be carried out.

Description

Technical Field

[0001] The present invention relates to a method for homogenizing black powder of lithium batteries, which is a pretreatment and purification method for the extraction of valuable metals from waste lithium batteries and chemical refining treatment. Background Art

[0002] The composition of a lithium battery generally includes electrodes (including positive and negative electrodes), a separator, an electrolyte, and a battery case, etc. Once the electrode materials of waste lithium batteries enter the environment, metal ions in the battery positive electrode, carbon dust in the negative electrode, strong alkalis and heavy metal ions in the electrolyte may cause serious environmental pollution. Therefore, waste lithium batteries need to be recycled. The treatment technology of waste lithium batteries can be divided into a physical pretreatment process, a process for extracting valuable metals, and a chemical refining process. Among them, the physical pretreatment technology mainly passes through a simple discharge treatment, and then uses a physical crushing and sorting process to process the waste battery into a mixed powder containing metals and mixed plastics (commonly known as black powder), and then proceeds with the subsequent extraction of valuable metals and chemical refining treatment. However, the current pretreatment methods for waste lithium batteries mainly use high-temperature treatment methods to extract metals or metal compounds from waste lithium batteries. This high-temperature treatment method has a fast reaction speed and short time consumption, but has a high cost, low purity of black powder, high high-temperature energy consumption, and a large amount of toxic waste gas will be generated by the electrolyte and binder at high temperature, which will cause secondary environmental pollution. Summary of the Invention

[0003] The main object of the present invention is to provide a method for homogenizing black powder of lithium batteries, which can effectively solve the disadvantage of poor purity of black powder in waste lithium batteries.

[0004] The method for homogenizing black powder of lithium batteries of the present invention includes the following steps:

[0005] (1) Put the black powder of lithium batteries into a reaction tank with controllable temperature for cleaning. The cleaning temperature is 50°C to 150°C, the cleaning time is 0.5 to 2 hours, and the composition of the cleaning solution is one or more of benzene, N-methylpyrrolidone, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, or halogen-containing alkanes;

[0006] (2) Perform a temperature-controlled filtration on the solid obtained from the cleaning in step (1). The filtration temperature is 50°C to 150°C, and the filtration time is 0.5 to 2 hours;

[0007] (3) Put the filter cake obtained in step (2) into a flotation tank, and use water to prepare the black powder into a floating ore pulp with a concentration of 5 to 35 wt%. Add a carbon capture agent and a foaming agent to the floating ore pulp. The addition amounts of the carbon capture agent and the foaming agent are 0.1 to 10% of the weight of the input black powder to obtain a carbon product and a metal salt sediment. If the carbon content in the metal salt sediment > 0.5 wt%, continue to put it into the flotation tank for flotation until the carbon content < 0.5 wt%;

[0008] (4) Magnetically separate the metal salt ore deposit with a carbon content of less than 0.5 wt% obtained in step (3), with a magnetic force intensity of 5000 - 30000 gauss, to remove the iron content contained therein.

[0009] (5) Eddy current separate the product obtained after magnetic separation in step (4) to remove the aluminum content contained therein.

[0010] (6) The solid obtained in step (5) is the metal salt concentrate containing lithium, manganese, cobalt, and nickel components, and is used for the extraction of valuable metals and chemical refining treatment in the subsequent steps.

[0011] The method for homogenizing black powder of lithium batteries according to the present invention has the advantages that: a program is developed for the pretreatment process of waste black powder of lithium batteries, which can reduce impurity components such as plastics and metals in the black powder, improve the purity of the black powder, facilitate the extraction of valuable metals and chemical refining treatment in the subsequent steps, and can avoid causing secondary pollution to the environment. Description of the Drawings

[0012] Figure 1 The following shows the composition table of the black powder of lithium batteries of the present invention.

[0013] Figure 2 The following shows the flow chart of the homogenization treatment of the black powder of lithium batteries of the present invention. Detailed Embodiments

[0014] Regarding the technical means adopted by the present invention to achieve the above-mentioned usage purposes and effects, preferred and feasible embodiments are now given, and are described in detail as follows in conjunction with the drawings shown:

[0015] For the method for homogenizing black powder of lithium batteries of the present invention, the composition of the black powder is as Figure 1 shown, and the treatment flow of the method for homogenizing black powder of lithium batteries is as Figure 2 shown, and the treatment steps are as follows:

[0016] (1) Put the black powder of lithium batteries into a reaction tank with controllable temperature for cleaning. The cleaning temperature is 50°C - 150°C, the cleaning time is 0.5 - 2 hours, and the composition of the cleaning solution is one or more of benzene, N-methylpyrrolidone (English name NMP), propylene glycol monomethyl ether (English name PGME), propylene glycol monomethyl ether acetate (English name PGMEA), or halogen-containing alkanes (such as dichloromethane).

[0017] (2) Perform a temperature-controllable filtration on the solid obtained by cleaning in step (1). The filtration temperature is 50°C - 150°C, and the filtration time is 0.5 - 2 hours.

[0018] (3) Put the filter cake obtained in step (2) into a flotation cell, and use water to prepare the black powder into a flotation pulp with a concentration of 5 - 35 wt%. Add a carbon capture agent (such as kerosene or diesel) and a foaming agent (such as turpentine) to the flotation pulp. The addition amounts of the carbon capture agent and the foaming agent are 0.1 - 10% of the weight of the input black powder to obtain a carbon product and a metal salt sediment. If the carbon content in the metal salt sediment > 0.5 wt%, continue to put it into the flotation cell for flotation until the carbon content < 0.5 wt%.

[0019] (4) Conduct magnetic separation on the metal salt sediment with a carbon content < 0.5 wt% obtained in step (3), with a magnetic intensity of 5000 - 30000 Gauss to remove the iron content contained therein.

[0020] (5) Conduct eddy current separation on the product obtained by magnetic separation in step (4) to remove the aluminum content contained therein.

[0021] (6) The solid obtained in step (5) is the metal salt concentrate containing lithium, manganese, cobalt, and nickel components, and subsequent extraction of valuable metals and chemical refining treatment can be carried out.

[0022] Example 1 of the present invention:

[0023] (1) Put the black powder of the lithium battery into a temperature - controllable reaction cell for cleaning. The cleaning temperature is 90°C, the cleaning time is 1 hour, and the composition of the cleaning liquid is benzene.

[0024] (2) Conduct temperature - controllable filtration on the solid obtained by cleaning in step (1). The filtration temperature is 90°C, and the filtration time is 1 hour.

[0025] (3) Put the filter cake obtained in step (2) into a flotation cell, and use water to prepare the black powder into a flotation pulp with a concentration of 20 wt%. Add 0.5 wt% kerosene and 0.5 wt% turpentine to the flotation pulp to obtain a carbon product and a metal salt sediment. If the carbon content in the metal salt sediment > 0.5 wt%, continue to put it into the flotation cell for flotation. By increasing the ratio, keep the concentration of the flotation pulp at 20 wt%, the concentration of the carbon capture agent at 0.5 wt%, and the concentration of the foaming agent at 0.5 wt% until the carbon content < 0.5 wt%.

[0026] (4) Conduct magnetic separation on the metal salt sediment with a carbon content < 0.5 wt% obtained by flotation in step (3), with a magnetic intensity of 30000 Gauss to remove the iron content contained therein.

[0027] (5) Conduct eddy current separation on the product obtained by magnetic separation in step (4) to remove the aluminum content contained therein.

[0028] (6) The obtained solid is the metal salt concentrate containing lithium, manganese, cobalt, and nickel components, and subsequent extraction of valuable metals and chemical refining treatment can be carried out.

[0029] In summary, the present invention has indeed achieved the intended use purpose and efficacy, and is more ideal and practical compared with the known technology. However, the above embodiments are only specific descriptions of the preferred embodiments of the present invention, and these embodiments are not used to limit the scope of the patent application of the present invention. Any equivalent changes and modifications made without departing from the technical means disclosed by the present invention should be included in the scope of the patent application covered by the present invention.

Claims

1. A method for homogenizing black powder of lithium batteries, characterized in that, The method includes the following steps: (1) Put the black powder of lithium battery into a reaction tank with controllable temperature for cleaning. The cleaning temperature is 50°C to 150°C, the cleaning time is 0.5 to 2 hours, and the composition of the cleaning solution is one or more of benzene, N-methylpyrrolidone, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, or halogen-containing alkanes; (2) Filter the solid obtained from the cleaning in step (1) at a controllable temperature. The filtration temperature is 50°C to 150°C, and the filtration time is 0.5 to 2 hours; (3) Put the filter cake obtained in step (2) into a flotation tank, and prepare the black powder into a floating ore pulp with a concentration of 5 to 35 wt% with water. Add a carbon capture agent and a foaming agent to the floating ore pulp. The addition amounts of the carbon capture agent and the foaming agent are 0.1 to 10% of the weight of the input black powder to obtain a carbon product and a metal salt sediment. If the carbon content in the metal salt sediment > 0.5 wt%, continue to put it into the flotation tank for flotation until the carbon content < 0.5 wt%; (4) Magnetically separate the metal salt sediment with a carbon content < 0.5 wt% obtained from the flotation in step (3) at a magnetic intensity of 5000 to 30000 gauss to remove the iron content contained therein; (5) Perform eddy current separation on the product obtained after magnetic separation in step (4) to remove the aluminum content contained therein; (6) The solid obtained in step (5) is the metal salt concentrate containing lithium, manganese, cobalt, and nickel components, which is used for the extraction of valuable metals and chemical refining treatment in the subsequent steps.

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