CN217676841U

CN217676841U - System for ternary lithium battery retrieves system lithium sulfate, lithium carbonate, lithium hydroxide

Info

Publication number: CN217676841U
Application number: CN202221805509.XU
Authority: CN
Inventors: 许明强; 肖彬彬; 施小林; 王大新
Original assignee: Hangzhou Jiangrongdao Environmental Technology Co ltd
Current assignee: Hangzhou Jiangrongdao Environmental Technology Co ltd
Priority date: 2022-07-12
Filing date: 2022-07-12
Publication date: 2022-10-28
Anticipated expiration: 2032-07-12

Abstract

The utility model relates to a system for ternary lithium cell retrieves system lithium sulfate, lithium carbonate, lithium hydroxide belongs to waste battery resource recovery technical field. The utility model discloses in smash the sorter and be connected with burner, incomplete slag bath and black powder pond respectively, black powder pond and dilute sulphuric acid configuration pond all are connected with the blendor, blendor and hydrogen pond all are connected with the rotary kiln, the rotary kiln is connected with steam tail gas processing unit and water immersion pond respectively, water immersion pond configuration pond is connected with the water immersion pond, the pure water case is connected with water immersion pond configuration pond, the water immersion pond is connected with lithium-containing stock solution pond, lithium-containing stock solution pond is connected with nickel cobalt manganese dry slag stock solution pond and UF membrane filter unit respectively, UF membrane filter unit is connected with backwash outer fluid-discharge reservoir and anion exchange resin unit respectively, backwash outer fluid-discharge reservoir and lithium adsorption unit are connected, lithium adsorption unit respectively with lithium carbonate centrifugal separation dry mother liquor pond and anion exchange resin unit connection.

Description

System for ternary lithium battery retrieves system lithium sulfate, lithium carbonate, lithium hydroxide

Technical Field

The utility model relates to a system for ternary lithium cell retrieves system lithium sulfate, lithium carbonate, lithium hydroxide belongs to waste battery resource recovery technical field.

Background

Lithium (Li) and its compounds are widely used in various fields such as electronics, metallurgy, chemical industry, medicine, energy and the like due to their excellent properties, have a very important strategic position in the construction of national economy and national defense, and are known as "new energy metal of the 21 st century" and "aerospace alloy of the open world". Meanwhile, the development and application of green pollution-free lithium ion power batteries drive the vigorous development of the international lithium market. Currently, the demand for lithium products in the international market is increasing at a rate of 7% to 11% per year and its momentum will continue to remain. As an important energy metal, the lithium market prospect is very attractive, the upstream salt lake lithium extraction technology in the lithium battery industry is relatively mature at present, the downstream battery manufacturing technology is also in iterative updating of fire and heat, the related technology and the industry are in the starting stage as the final lithium battery recycling, the lithium battery recycling fills the last cycle of the lithium battery industry, and the lithium battery recycling has different meanings.

The ternary polymer lithium battery refers to a lithium battery of which the anode material is a ternary anode material of lithium nickel cobalt manganese or lithium nickel cobalt aluminate, and the anode materials of the lithium battery are various and mainly comprise lithium cobaltate, lithium manganate, lithium nickelate, ternary materials, lithium iron phosphate and the like. The battery using the lithium iron phosphate as the anode material has long charge-discharge cycle life, but has the defects of large differences in energy density, high-low temperature performance and charge-discharge rate characteristics, high production cost and development bottleneck of the lithium iron phosphate battery technology and application; the lithium manganate battery has low energy density and poor cycling stability and storage performance at high temperature, so the lithium manganate is only used as a positive electrode material of the international 1 st generation power lithium battery; the multi-element material is increasingly concerned and accepted by the industry due to the double advantages of comprehensive performance and cost, and gradually surpasses the technical route that lithium iron phosphate and lithium manganate become mainstream. The battery core made of the ternary material replaces a widely used lithium cobaltate battery core, and is widely used in the field of notebook batteries.

At present, the domestic lithium battery recycling enterprises mainly adopt a wet method as a main process for recycling. The recovery of the anode material of the waste lithium battery generally comprises a pyrogenic process, a wet process and a pyrogenic-wet process combined treatment process. The pyrometallurgical process has the advantages of high treatment capacity and the like, but also has the defects of high energy consumption, low yield of valuable elements such as cobalt, nickel, lithium and the like; the traditional wet process has the advantages of high leaching rate of valuable elements and the like, but the separation and purification processes of all elements in the leaching solution are complex.

The lithium recovery process route of the lithium battery has large difference. Lithium extraction process routes of lithium battery recovery enterprises are different greatly, for example, in a lithium iron phosphate battery recovery process flow, a lithium extraction link selects an oxidation reducing agent, an acid-base agent and the like; for example, in the process flow of recovering the ternary battery, the selection of a pyrogenic method or a wet method, the sequential selection of lithium extraction and nickel cobalt extraction, the selection of a lithium extraction purification process (membrane separation, ion exchange and precipitation) and the like are performed in a lithium leaching link. The difference of the process route also directly causes the great difference of the lithium yield and the processing cost of each family at present.

In view of this, patent document No. 202111295825.7 discloses a method for preferentially extracting lithium from a waste ternary lithium ion battery positive electrode material and recovering valuable metals, and the prior art includes the following steps: disassembling, crushing and sorting the waste ternary lithium battery to obtain waste battery anode powder; step two: stirring and mixing the waste battery anode powder with concentrated sulfuric acid uniformly, and roasting at the temperature of 400-600 ℃; step three: the roasted material is loose solid, the procedures such as crushing and the like are not needed, pure water is added for direct leaching, the pH value of a leaching solution is adjusted to 10.0-10.5 by using a dilute alkali solution in the leaching process, and leaching slag and a leaching solution are obtained after leaching, and the leaching solution is used for preparing Li2CO3 or lithium hydroxide; step four: leaching valuable metal elements of cobalt, nickel and manganese in the leaching residue by adopting a reduction acid leaching method, and then preparing corresponding cobalt, nickel and manganese products after impurity removal, extraction and separation. Compared with the prior art, the method can produce the battery-grade pure lithium salt with higher value through multi-stage electrodialysis concentration and BP bipolar membrane electrodialysis.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to overcome the above-mentioned not enough that exists among the prior art, and provide a system of lithium sulfate, lithium carbonate, lithium hydroxide is retrieved to three lithium batteries that structural design is reasonable.

The utility model provides a technical scheme that above-mentioned problem adopted is: the system for recycling the lithium sulfate, the lithium carbonate and the lithium hydroxide to prepare the lithium sulfate, the lithium carbonate and the lithium hydroxide comprises a first stage, a second stage, a third stage and a fourth stage, wherein the first stage comprises a crushing separator, a combustion device and a residue pool, and the second stage comprises a black powder pool, a mixer, a dilute sulfuric acid preparation pool, a rotary kiln, a hydrogen pool, a steam tail gas treatment unit, a water immersion pool, a water immersion liquid preparation pool, a pure water tank, a first lithium hydroxide solution pool, a lithium-containing stock solution pool, a nickel-cobalt-manganese dry residue stock solution pool, a UF membrane filtration unit, a backwashing external liquid discharge pool, a lithium adsorption unit, a lithium carbonate centrifugal separation drying mother solution pool and an anion exchange resin unit;

the crushing and sorting machine is respectively connected with a combustion device, a residue pool and a black powder pool, the black powder pool and a dilute sulfuric acid configuration pool are respectively connected with a mixer, the mixer and a hydrogen pool are respectively connected with a rotary kiln, the rotary kiln is respectively connected with a steam tail gas treatment unit and a water immersion pool, the water immersion pool is connected with a water immersion pool, a pure water tank is connected with a water immersion pool, the water immersion pool is connected with a lithium-containing stock solution pool, the lithium-containing stock solution pool is respectively connected with a nickel-cobalt-manganese dry residue stock solution pool and a UF membrane filtering unit, the UF membrane filtering unit is respectively connected with a backwashing external liquid discharge pool and an anion exchange resin unit, the backwashing external liquid discharge pool is connected with a lithium adsorption unit, and the lithium adsorption unit is respectively connected with a lithium carbonate centrifugal separation dry mother solution pool and an anion exchange resin unit,

the structure is characterized in that: the third stage comprises a multi-stage electrodialysis concentration unit, an electrodialysis desalination liquid tank, a lithium sulfate rich concentrated water tank, a chelating resin unit, a low-purity lithium sulfate mother liquid tank, a high-purity lithium sulfate rich concentrated water tank, a lithium precipitation conversion reaction unit, a sodium carbonate soda unit and a BP bipolar membrane electrodialysis unit, and the fourth stage comprises a lithium carbonate centrifugal separation disc type drying unit, a first MVR evaporation crystallization unit, a second lithium hydroxide solution tank and a second MVR evaporation crystallization unit;

the anion exchange resin unit is connected with a multistage electrodialysis concentration unit, the multistage electrodialysis concentration unit is respectively connected with an electrodialysis desalination liquid tank and a lithium sulfate-rich concentrated water tank, the electrodialysis desalination liquid tank is connected with a water immersion liquid configuration tank, a lithium hydroxide solution tank is connected with a pipeline between the electrodialysis desalination liquid tank and the water immersion liquid configuration tank, the lithium sulfate-rich concentrated water tank is connected with a chelate resin unit, the chelate resin unit is connected with a high-purity lithium sulfate-rich concentrated water tank, the high-purity lithium sulfate-rich concentrated water tank is respectively connected with a lithium precipitation conversion reaction unit, a BP bipolar membrane electrodialysis unit and a first MVR evaporation crystallization unit, a sodium carbonate soda unit is connected with a lithium precipitation conversion reaction unit, the lithium precipitation conversion reaction unit is connected with a lithium carbonate centrifugal separation disc type drying unit, the lithium carbonate centrifugal separation disc type drying unit is connected with a lithium adsorption unit, the BP bipolar membrane electrodialysis unit is respectively connected with a dilute sulfuric acid configuration tank, a low-purity lithium sulfate mother solution tank and a second MVR evaporation crystallization tank, the low-purity sulfate mother solution tank is respectively connected with the anion exchange resin solution tank, the anion exchange resin tank and the multistage electrodialysis concentration unit, and the water immersion liquid configuration tank are respectively connected with a second MVR evaporation crystallization tank. UF ultrafiltration backwash water and sodium carbonate centrifugation mother liquor are mixed and enter an adsorption system to carry out lithium element recovery treatment again, which greatly contributes to improving the recovery rate of metal lithium.

Further, the mixer, the dilute sulfuric acid preparation pool, the rotary kiln, the hydrogen pool and the steam tail gas treatment unit form a sulfating hydrogenation reduction roasting lithium extraction section, and the water immersion pool, the water immersion liquid preparation pool, the pure water tank, the first lithium hydroxide solution pool, the lithium-containing stock solution pool and the nickel-cobalt-manganese dry residue raw material pool form a water immersion section.

Further, the first stage is a black powder sorting and extracting stage, the second stage is a pretreatment impurity removing stage, the third stage is an extreme lithium extraction concentration stage, and the fourth stage is an exquisite lithium product stage. Through the matching among all the stages and the control of the operation parameters, the recovery rate of the lithium element can reach more than 99.9 percent, and the purity can reach more than 99.99 percent.

Further, the multistage electrodialysis concentration unit comprises a first-stage electrodialysis concentration unit and a second-stage electrodialysis concentration unit, the first-stage electrodialysis concentration unit comprises a first-stage desalting tank, a first-stage desalting solution circulating pump, a first-stage concentration tank, a first-stage concentrating solution circulating pump, a first-stage cathode solution tank, a first-stage catholyte circulating pump, a first-stage anode solution tank, a first-stage anolyte circulating pump and a first-stage electrodialysis membrane stack, and the second-stage electrodialysis concentration unit comprises a second-stage desalting tank, a second-stage desalting solution circulating pump, a second-stage concentration tank, a second-stage concentrating solution circulating pump, a second-stage cathode solution tank, a second-stage catholyte circulating pump, a second-stage anode solution tank, a second-stage anolyte circulating pump and a second-stage electrodialysis membrane stack;

the first channels of the first-stage desalting tank, the first-stage desalting solution circulating pump and the first-stage electrodialysis membrane stack are sequentially and circularly connected and form the first circulation of the first-stage electrodialysis concentration unit, the second channels of the first-stage concentrating tank, the first-stage concentrating solution circulating pump and the first-stage electrodialysis membrane stack are sequentially and circularly connected and form the second circulation of the first-stage electrodialysis concentration unit, the cathodes of the first-stage cathode solution tank, the first-stage cathode solution circulating pump and the first-stage electrodialysis membrane stack are sequentially and circularly connected and form the third circulation of the first-stage electrodialysis concentration unit, the anodes of the first-stage anode solution tank, the first-stage anode solution circulating pump and the first-stage electrodialysis membrane stack are sequentially and circularly connected and form the third circulation of the first-stage electrodialysis concentration unit,

the utility model discloses a desalination device, including one-level desalination case, second grade electrodialysis membrane stack, second grade desalination case, second grade desalination liquid circulating pump, second grade electrodialysis membrane stack, second grade cathode liquid case, second grade cathode liquid circulating pump and second grade electrodialysis membrane stack, the first circulation that first grade desalination case and first grade concentrate case are connected with second grade desalination case and second grade concentrate case respectively, the first passageway of second grade desalination case, second grade desalination liquid circulating pump and second grade electrodialysis membrane stack is cyclic connection in proper order to form the first circulation of second grade electrodialysis concentration unit, second grade concentrate case, second grade cathode liquid circulating pump and second grade electrodialysis membrane stack are cyclic connection in proper order to form the third circulation of second grade electrodialysis concentration unit, the positive pole of second grade anode liquid case, second grade anode liquid circulating pump and second grade electrodialysis membrane stack is cyclic connection in proper order to form the third circulation of second grade electrodialysis concentration unit.

Further, the first-stage electrodialysis concentration unit further comprises a first lifting pump and a second lifting pump, the raw water tank of the multistage electrodialysis concentration unit is connected with the first lifting pump, the first lifting pump is connected with the first desalting tank, the first concentrating tank is connected with the raw water tank of the chelate resin unit, and the raw water tank of the chelate resin unit is connected with the second lifting pump. The concentration of the lithium ions is increased from 0.5-1.5g/L to more than 15-20 g/L.

Furthermore, in the first-stage electrodialysis membrane stack, the anion exchange membrane and the cation exchange membrane are both positioned between the cathode and the anode, and a first channel or a second channel is formed between the adjacent anion exchange membrane and the adjacent cation exchange membrane.

Further, the BP bipolar membrane electrodialysis unit comprises a salt solution water tank, a salt solution circulating pump, an acid solution water tank, an acid solution circulating pump, an alkali solution water tank, an alkali solution circulating pump, a cathode solution tank, a cathode solution circulating pump, an anode solution tank, an anode solution circulating pump and a BP bipolar membrane electrodialysis membrane stack,

the salt solution water tank, the salt solution circulating pump and the first channel of the BP bipolar membrane electrodialysis membrane stack are sequentially and circularly connected to form the first cycle of the BP bipolar membrane electrodialysis membrane stack, the acid solution water tank, the acid solution circulating pump and the second channel of the BP bipolar membrane electrodialysis membrane stack are sequentially and circularly connected to form the second cycle of the BP bipolar membrane electrodialysis membrane stack, the alkali solution water tank, the alkali solution circulating pump and the third channel of the BP bipolar membrane electrodialysis membrane stack are sequentially and circularly connected, and a third circulation of the BP bipolar membrane electrodialysis membrane stack is formed, the cathode liquid tank, the cathode liquid circulating pump and the cathode of the BP bipolar membrane electrodialysis membrane stack are sequentially and circularly connected, and a fourth circulation of the BP bipolar membrane electrodialysis membrane stack is formed, and the anode liquid tank, the anode liquid circulating pump and the anode of the BP bipolar membrane electrodialysis membrane stack are sequentially and circularly connected, and a fourth circulation of the BP bipolar membrane electrodialysis membrane stack is formed. And (3) refluxing, mixing and refluxing the lithium hydroxide alkaline solution produced by the back-end BP bipolar membrane electrodialysis unit and the electrodialysis desalination solution to flow back into the water immersion solution preparation tank, mixing and preparing the water immersion solution into pure water, and controlling the pH to be 11-12, so that about 5% of nickel, cobalt and manganese in the lithium sulfate solution after water immersion can be removed. So that the nickel-cobalt-manganese content in the lithium sulfate solution after water leaching is reduced to about 1 percent.

Further, the BP bipolar membrane electrodialysis unit further comprises a lift pump, a raw water tank of the BP bipolar membrane electrodialysis unit is connected with the lift pump, the lift pump is connected with a salt solution water tank, an acid solution water tank is connected with a dilute sulfuric acid preparation tank, and an alkali solution water tank is respectively connected with a water immersion solution preparation tank and a second MVR evaporation crystallization unit. Sulfuric acid produced by the BP bipolar membrane electrodialysis unit is recycled for the front end sulfating, reducing, roasting and lithium extracting section, and dilute sulfuric acid is used for diluting concentrated sulfuric acid, so that the concentration of the sulfuric acid is controlled to be 40-50%, the consumption of the front end sulfuric acid is greatly reduced, and the consumption of diluted pure water is also reduced.

Furthermore, in the electrodialysis membrane stack of the BP bipolar membrane, an anion exchange membrane, a cation exchange membrane and the bipolar membrane are all positioned between a cathode and an anode, a first channel is formed between the cation exchange membrane and the anion exchange membrane, a second channel is formed between the anion exchange membrane and the anode of the bipolar membrane, a third channel is formed between the cathode of the bipolar membrane and the cation exchange membrane, the first channel is a salt solution channel, the second channel is an acid solution channel, and the third channel is an alkali solution channel.

Compared with the prior art, the utility model has the advantages of it is following:

1) In the whole process, dilute sulfuric acid required by the front-end sulfating, hydrogenation, reduction, roasting and lithium extraction section is recycled through the bipolar membrane system obtained in the later stage, and the loss of the system is as low as below 0.1%. The added lithium sulfate conversion agent (sodium carbonate agent) hardly has any loss, and more than 99.9 percent of the lithium sulfate is converted into a lithium carbonate product; in the process, any sodium hydroxide (caustic soda) product required in the conventional lithium battery recovery treatment is not added, the addition amount of sulfuric acid is greatly reduced due to high recovery utilization rate, the lithium precipitation yield of the sodium carbonate can reach more than 99.9 percent, and other medicaments are hardly used in other processes. Therefore, the dosage and cost of the medicament in the lithium battery recovery process are greatly reduced.

2) The method has the advantages that the complexity of the traditional treatment process is greatly reduced only by simple UF membrane filtration and resin adsorption and the process alternation of electrodialysis and bipolar membrane electrodialysis, and the problems of too complicated separation and purification processes and low purity of the traditional recovery process are solved.

3) In addition, in the whole lithium battery recovery process, the discharge of metallic lithium elements is only discharge of lithium with the concentration of below 0.1% in backwashing discharge water of the adsorption unit, and the recovery rate of the metallic lithium in the whole process can reach above 99.9%. Compared with the traditional process, the method has the advantages that the method is greatly improved by 80-85%, and the battery grade pure lithium salt (lithium carbonate and lithium hydroxide) product with higher value is produced, so that the profitability of the recovery enterprise is improved.

Drawings

Fig. 1 is a schematic connection relationship diagram of a system for recovering lithium sulfate, lithium carbonate and lithium hydroxide from a ternary lithium battery according to an embodiment of the present invention.

Fig. 2 is a schematic structural diagram of a multi-stage electrodialysis concentration unit according to an embodiment of the present invention.

Fig. 3 is a schematic structural diagram of a BP bipolar membrane electrodialysis unit according to an embodiment of the present invention.

In the figure: a first stage 1, a second stage 2, a third stage 3, a fourth stage 4, a sulfating hydrogenation reduction roasting lithium extraction stage 5, a water leaching stage 6,

A crushing and sorting machine 11, a combustion device 12, a residue tank 13,

A black powder pool 21, a mixer 22, a dilute sulphuric acid configuration pool 23, a rotary kiln 24, a hydrogen pool 25, a steam tail gas treatment unit 26, a water immersion pool 27, a water immersion liquid configuration pool 28, a pure water tank 29, a lithium hydroxide solution pool 210, a lithium-containing stock solution pool 211, a nickel-cobalt-manganese dry slag stock pool 212, a UF membrane filtration unit 213, a backwashing external liquid discharge pool 214, a lithium adsorption unit 215, a lithium carbonate centrifugal separation dry mother solution pool 216, an anion exchange resin unit 217, a lithium carbonate centrifugal separation dry mother solution pool 216, a lithium ion exchange resin unit 217, a lithium ion exchange resin unit,

A multi-stage electrodialysis concentration unit 31, an electrodialysis desalination liquid tank 32, a lithium sulfate rich concentrated water tank 33, a chelating resin unit 34, a low-purity lithium sulfate mother liquid tank 35, a high-purity lithium sulfate rich concentrated water tank 36, a lithium precipitation conversion reaction unit 37, a sodium carbonate soda unit 38, a BP bipolar membrane electrodialysis unit 39, a,

A lithium carbonate centrifugal separation disc type drying unit 41, a first MVR evaporation and crystallization unit 42, a second lithium hydroxide solution tank 43, a second MVR evaporation and crystallization unit 44,

A first-stage electrodialysis concentration unit A1, a second-stage electrodialysis concentration unit A2,

A first-stage desalting tank A11, a first-stage desalting liquid circulating pump A12, a first-stage concentrating tank A13, a first-stage concentrating liquid circulating pump A14, a first-stage catholyte tank A15, a first-stage catholyte circulating pump A16, a first-stage anolyte tank A17, a first-stage anolyte circulating pump A18, a first-stage electrodialysis membrane stack A19, a first lift pump A110, a second lift pump A111, a third lift pump A13, a fourth lift pump A15, a fourth lift pump A16, a fourth lift pump A17, a fifth lift pump A17, a sixth lift pump A18, a fifth lift pump B,

A secondary desalting tank A21, a secondary desalting solution circulating pump A22, a secondary concentrating tank A23, a secondary concentrating solution circulating pump A24, a secondary cathode solution tank A25, a secondary cathode solution circulating pump A26, a secondary anode solution tank A27, a secondary anode solution circulating pump A28, a secondary electrodialysis membrane stack A29,

The device comprises a salt solution water tank B1, a salt solution circulating pump B2, an acid solution water tank B3, an acid solution circulating pump B4, an alkali solution water tank B5, an alkali solution circulating pump B6, a cathode solution tank B7, a cathode solution circulating pump B8, an anode solution tank B9, an anode solution circulating pump B10, a BP bipolar membrane electrodialysis membrane stack B11 and a lift pump B12.

Detailed Description

The present invention will be described in further detail by way of examples with reference to the accompanying drawings, which are illustrative of the present invention and are not intended to limit the present invention.

Examples are given.

Referring to fig. 1 to 3, it should be understood that the structures, ratios, sizes, etc. shown in the drawings attached to the present specification are only used for matching with the contents disclosed in the specification, so as to be known and read by those skilled in the art, and are not used for limiting the limit conditions that the present invention can be implemented, so that the present invention has no technical essence, and any modification of the structures, changes of the ratio relationship, or adjustment of the sizes should still fall within the scope that the technical contents disclosed in the present invention can cover without affecting the efficacy and the achievable purpose of the present invention. Meanwhile, in the present specification, if there are terms such as "upper", "lower", "left", "right", "middle" and "one", they are used for clarity of description only, and are not intended to limit the scope of the present invention, and changes or adjustments of the relative relationship thereof are considered as the scope of the present invention without substantial changes in the technical content.

The system for recycling and preparing lithium sulfate, lithium carbonate and lithium hydroxide by using the ternary lithium battery in the embodiment comprises a first stage 1, a second stage 2, a third stage 3 and a fourth stage 4, wherein the first stage 1 is a black powder sorting and extracting stage, the second stage 2 is a pretreatment impurity removing stage, the third stage 3 is a lithium concentration extremely-raising stage, and the fourth stage 4 is a lithium product refining stage.

The first stage 1 in this embodiment includes a crushing and sorting machine 11, a combustion apparatus 12, and a residue tank 13, the second stage 2 includes a black powder tank 21, a mixer 22, a dilute sulfuric acid preparation tank 23, a rotary kiln 24, a hydrogen tank 25, a steam tail gas treatment unit 26, a water immersion tank 27, a water immersion liquid preparation tank 28, a pure water tank 29, a first lithium hydroxide solution tank 210, a lithium-containing raw liquid tank 211, a nickel-cobalt-manganese dry residue raw material tank 212, a UF membrane filtration unit 213, a backwash external liquid discharge tank 214, a lithium adsorption unit 215, a lithium carbonate centrifugal separation dry mother liquid tank 216, and an anion exchange resin unit 217, the third stage 3 includes a multistage electrodialysis concentration unit 31, an electrodialysis desalination liquid tank 32, a lithium sulfate-rich concentrated water tank 33, a chelate resin unit 34, a low-purity lithium sulfate mother liquid tank 35, a high-purity lithium sulfate-rich water tank 36, a lithium precipitation conversion reaction unit 37, a sodium carbonate soda unit 38, and a BP bipolar membrane unit 39, and the fourth stage 4 includes a lithium carbonate centrifugal separation disc drying unit 41, a first MVR evaporative crystallization unit 42, a second MVR evaporative crystallization unit 43, and a second MVR evaporative crystallization unit 44.

In this embodiment, the mixer 22, the dilute sulfuric acid preparation tank 23, the rotary kiln 24, the hydrogen tank 25, and the steam tail gas treatment unit 26 constitute a lithium extracting section by sulfating, hydrogenation, reduction, and roasting, and the water immersion tank 27, the water immersion tank 28, the pure water tank 29, the first lithium hydroxide solution tank 210, the lithium-containing stock solution tank 211, and the nickel-cobalt-manganese dry slag stock tank 212 constitute a water immersion section.

In this embodiment, the crushing separator 11 is connected to the combustion device 12, the residue tank 13 and the black powder tank 21, the black powder tank 21 and the dilute sulfuric acid preparation tank 23 are connected to the mixer 22, the mixer 22 and the hydrogen tank 25 are connected to the rotary kiln 24, the rotary kiln 24 is connected to the steam tail gas treatment unit 26 and the water immersion tank 27, the water immersion tank 28 is connected to the water immersion tank 27, the purified water tank 29 is connected to the water immersion tank 28, the water immersion tank 27 is connected to the lithium-containing raw liquid tank 211, the lithium-containing raw liquid tank 211 is connected to the nickel-cobalt-manganese dry residue raw liquid tank 212 and the UF membrane filtration unit 213, the UF membrane filtration unit 213 is connected to the backwash external liquid discharge tank 214 and the anion exchange resin unit 217, the backwash external liquid discharge tank 214 is connected to the lithium adsorption unit 215, the lithium adsorption unit 215 is connected to the lithium carbonate centrifugal separation dry mother liquid tank 216 and the anion exchange resin unit 217, the anion exchange resin unit 217 is connected with the multi-stage electrodialysis concentration unit 31, the multi-stage electrodialysis concentration unit 31 is respectively connected with the electrodialysis desalination liquid tank 32 and the lithium sulfate rich concentrated water tank 33, the electrodialysis desalination liquid tank 32 is connected with the water immersion liquid configuration tank 28, the first lithium hydroxide solution tank 210 is connected with a pipeline between the electrodialysis desalination liquid tank 32 and the water immersion liquid configuration tank 28, the lithium sulfate rich concentrated water tank 33 is connected with the chelating resin unit 34, the chelating resin unit 34 is connected with the high-purity lithium sulfate rich concentrated water tank 36, the high-purity lithium sulfate rich concentrated water tank 36 is respectively connected with the lithium deposition conversion reaction unit 37, the BP bipolar membrane electrodialysis unit 39 and the first MVR evaporation crystallization unit 42, the sodium carbonate soda unit 38 is connected with the lithium deposition conversion reaction unit 37, the lithium deposition conversion reaction unit 37 is connected with the lithium carbonate centrifugal separation disc type drying unit 41, the lithium carbonate centrifugal separation disc type drying unit 41 is connected with the lithium adsorption unit 215, the BP bipolar membrane electrodialysis unit 39 is respectively connected with the dilute sulfuric acid preparation tank 23, the low-purity lithium sulfate mother liquor tank 35 and the second lithium hydroxide solution tank 43, the low-purity lithium sulfate mother liquor tank 35 is connected with a pipeline between the anion exchange resin unit 217 and the multistage electrodialysis concentration unit 31, and the second lithium hydroxide solution tank 43 is respectively connected with the second MVR evaporation crystallization unit 44 and the water immersion solution preparation tank 28.

The multistage electrodialysis concentration unit 31 in this embodiment includes a first-stage electrodialysis concentration unit A1 and a second-stage electrodialysis concentration unit A2, the first-stage electrodialysis concentration unit A1 includes a first-stage desalination tank a11, a first-stage desalination liquid circulation pump a12, a first-stage concentration tank a13, a first-stage concentration liquid circulation pump a14, a first-stage cathode liquid tank a15, a first-stage cathode liquid circulation pump a16, a first-stage anode liquid tank a17, a first-stage anode liquid circulation pump a18, a first-stage electrodialysis membrane stack a19, a first lift pump a110, and a second lift pump a111, the second-stage electrodialysis concentration unit A2 includes a second-stage desalination tank a21, a second-stage desalination liquid circulation pump a22, a second-stage concentration tank a23, a second-stage concentration liquid circulation pump a24, a second-stage cathode liquid tank a25, a second-stage cathode liquid circulation pump a26, a second-stage anode liquid tank a27, a second-stage anode liquid circulation pump a28, and a second-stage electrodialysis membrane stack a29.

In this embodiment, first channels of the first-stage desalting tank a11, the first-stage desalting solution circulating pump a12, and the first-stage electrodialysis membrane stack a19 are sequentially and circularly connected, and form a first circulation of the first-stage electrodialysis concentration unit A1, the first-stage concentrating tank a13, the first-stage concentrating solution circulating pump a14, and the second channel of the first-stage electrodialysis membrane stack a19 are sequentially and circularly connected, and form a second circulation of the first-stage electrodialysis concentration unit A1, the first-stage cathode solution tank a15, the first-stage cathode solution circulating pump a16, and the cathode of the first-stage electrodialysis membrane stack a19 are sequentially and circularly connected, and form a third circulation of the first-stage electrodialysis concentration unit A1, and anodes of the first-stage anode solution tank a17, the first-stage anode solution circulating pump a18, and the first-stage electrodialysis membrane stack a19 are sequentially and circularly connected, and form a third circulation of the first-stage electrodialysis concentration unit A1.

In this embodiment, the raw water tank of the multistage electrodialysis concentration unit 31 is connected to the first lift pump a110, the first lift pump a110 is connected to the first desalting tank a11, the first concentrating tank a13 is connected to the raw water tank of the chelate resin unit 34, the raw water tank of the chelate resin unit 34 is connected to the second lift pump a111, the first desalting tank a11 and the first concentrating tank a13 are respectively connected to the second desalting tank a21 and the second concentrating tank a23, the second desalting tank a21, the second desalting liquid circulating pump a22 and the first channel of the second electrodialysis membrane stack a29 are sequentially and circularly connected to form the first cycle of the second electrodialysis concentration unit A2, the second concentrating tank a23, the second concentrating liquid circulating pump a24 and the second channel of the second electrodialysis membrane stack a29 are sequentially and circularly connected to form the second cycle of the second electrodialysis concentration unit A2, the second cathode liquid tank a25, the second cathode liquid circulating pump a26 and the cathode of the second electrodialysis membrane stack a29 are sequentially and circularly connected to form the third cycle of the second electrodialysis concentration unit A2, the second cathode liquid circulating pump a27 and the second electrodialysis membrane stack a29 are sequentially connected to form the second electrodialysis anode circulation pump a circulation unit A2.

In the first-stage electrodialysis membrane stack a19 in this embodiment, the anion exchange membrane a and the cation exchange membrane C are both located between the cathode and the anode, and a first channel or a second channel is formed between the adjacent anion exchange membrane a and the cation exchange membrane C, in the second-stage electrodialysis membrane stack a29, the anion exchange membrane a and the cation exchange membrane C are both located between the cathode and the anode, and a first channel or a second channel is formed between the adjacent anion exchange membrane a and the cation exchange membrane C, the first channel is a desalted liquid channel, and the second channel is a concentrated liquid channel.

The BP bipolar membrane electrodialysis unit 39 in this embodiment includes a salt solution water tank B1, a salt solution circulating pump B2, an acid solution water tank B3, an acid solution circulating pump B4, an alkali solution water tank B5, an alkali solution circulating pump B6, a cathode solution tank B7, a cathode solution circulating pump B8, an anode solution tank B9, an anode solution circulating pump B10, a BP bipolar membrane electrodialysis membrane stack B11, and a lift pump B12.

In this embodiment, a raw water tank of a BP bipolar membrane electrodialysis unit 39 is connected to a lift pump B12, the lift pump B12 is connected to a salt solution water tank B1, the salt solution water tank B1, a salt solution circulating pump B2 and a first channel of the BP bipolar membrane electrodialysis membrane stack B11 are sequentially and circularly connected to form a first cycle of the BP bipolar membrane electrodialysis membrane stack B11, an acid solution water tank B3, an acid circulating pump B4 and a second channel of the BP bipolar membrane electrodialysis membrane stack B11 are sequentially and circularly connected to form a second cycle of the BP bipolar membrane electrodialysis membrane stack B11, an alkali solution water tank B5, an alkali solution circulating pump B6 and a third channel of the BP bipolar membrane electrodialysis membrane stack B11 are sequentially and circularly connected to form a third cycle of the BP bipolar membrane electrodialysis membrane stack B11, a cathode solution tank B7, a cathode solution circulating pump B8 and a cathode of the BP bipolar membrane electrodialysis membrane stack B11 are sequentially and circularly connected to form a fourth cycle of the BP bipolar membrane electrodialysis membrane stack B11, an anode solution tank B9, an anode solution tank B10 and a BP bipolar membrane electrodialysis membrane stack B11 are sequentially connected to form a fourth cycle tank of an MVR circulation tank, and an evaporation dilute acid solution circulation tank B23 and an MVR circulation tank are configured to form a crystallization tank B11, and an evaporation crystallization tank B11.

In the BP bipolar membrane electrodialysis membrane stack B11 in this embodiment, the anion exchange membrane a, the cation exchange membrane C, and the bipolar membrane BP are all located between the cathode and the anode, a first channel is formed between the cation exchange membrane C and the anion exchange membrane a, a second channel is formed between the anion exchange membrane a and the anode of the bipolar membrane BP, a third channel is formed between the cathode of the bipolar membrane BP and the cation exchange membrane C, the first channel is a saline solution channel, the second channel is an acid solution channel, and the third channel is an alkali solution channel.

The method for recycling lithium sulfate, lithium carbonate and lithium hydroxide from the ternary lithium battery in the embodiment comprises the following steps:

1. sorting and extracting

The sorting and extracting process section mainly aims to disassemble the waste lithium batteries and then sort the waste lithium batteries according to different battery components to obtain a part mainly containing metal lithium in the lithium batteries, and then convert a mixed mixture containing solid lithium substances into a lithium-containing solution for further extraction treatment in a subsequent process.

S1, firstly, a large quantity of waste ternary lithium batteries enter a crushing and sorting machine 11 for crushing and sorting, and the crushing and sorting process equipment for the ternary lithium batteries is mature and simple in process at present. After multiple crushing and screening in the process, the batteries can be basically classified according to different assemblies to obtain corresponding parts, wherein copper, aluminum, thin films and magnetic metal residues in the ternary lithium battery enter the residue tank 13 and can be completely removed, in addition, volatile substances such as electrolyte and electrolyte in the ternary lithium battery are finally treated by a method of heat storage combustion treatment of the combustion device 12 to reach the standard and discharged, and finally, black powder (a mixture of metal lithium, nickel, cobalt and manganese) which is a lithium battery material mainly containing metal lithium, nickel, cobalt and manganese enters the black powder tank 21.

2. Impurity removal by pretreatment

1. Lithium extraction section by sulfating hydrogenation reduction roasting

S2, the black powder containing the metal lithium, the nickel, the cobalt and the manganese obtained at the previous stage enters a black powder pool 21 of a lithium extraction section 5 through sulfating hydrogenation reduction roasting, the conversion salt extraction of the metal lithium is carried out, and impurities such as the nickel, the cobalt, the manganese and the like are removed as far as possible.

S3, a sulfation hydrogenation reduction roasting lithium extraction section 5,1) firstly, the ternary positive black powder and 40-50% of dilute sulfuric acid are fully and uniformly mixed in a mixer 22, then the mixture is conveyed into a rotary kiln 24 through a conveyer belt, 2) high-purity hydrogen is introduced into the mixture, air is isolated in the process, cobalt, nickel and manganese oxides in the ternary positive black powder are reduced into metal simple substances or low-valent oxides under the high-temperature condition of 500-600 ℃ by utilizing the reducibility of hydrogen, and lithium metal and oxides thereof are converted into lithium sulfate under the action of sulfuric acid.

2. Water immersion section

S4, a water leaching section 6, dissolving dry slag discharged from the rotary kiln 24 in water after entering a water leaching tank 27 in a water leaching mode to form a soluble lithium sulfate solution, entering a lithium-containing stock solution tank 211, and leaving nickel-cobalt-manganese metal in the dry slag to form nickel-cobalt-manganese dry slag, and entering a nickel-cobalt-manganese dry slag stock tank 212, so as to achieve separation of lithium and nickel-cobalt-manganese, wherein the nickel-cobalt-manganese dry slag can be used as a raw material for other processes for recovering and refining nickel-cobalt-manganese, in the process, a reasonable acid-material ratio and the uniformity of mixed materials are key factors influencing the process effect, generally, 5% of nickel-cobalt-manganese in the process of the water leaching section 6 enters a lithium sulfate solution in a nickel-cobalt-manganese salt form, so that before subsequent lithium salt preparation, an alkali reagent is generally added to adjust the pH value of the system to 11-12, so that metals such as nickel and the like are precipitated and recovered in a hydroxide form, the lithium sulfate alkaline solution produced by a BP bipolar membrane unit 39 and an electrodialysis desalination unit 31 is configured in an electrodialysis desalination solution, the electrodialysis water leaching tank 28 is configured to further control the concentration of lithium sulfate solution after lithium sulfate solution is treated, and the lithium sulfate solution is further, the lithium sulfate solution is configured to be enriched in the water leaching tank, the lithium sulfate solution with the lithium sulfate concentration of which is controlled to be about 1-1.1-1-12, and the lithium sulfate solution.

3. UF membrane filtration

S5, after the processes of the front-end sulfating hydrogenation reduction roasting lithium extraction section 5 and the water leaching section 6, about 1% of nickel-cobalt-manganese sulfate is contained in the lithium-containing stock solution (lithium sulfate solution), and lithium salt needs to be further removed and refined, 1) the lithium-containing stock solution (lithium sulfate solution) is lifted from the lithium-containing stock solution pool 211 through a lifting pump and filtered through an ultrafiltration membrane in the UF membrane filtering unit 213, so that suspended matters (mainly metal residues and the like during water leaching of the previous stage) in the solution are removed.

Introduction of ultrafiltration: the water produced by the medium filter with pressure enters an ultrafiltration device, so that suspended matters and colloid in the water are further removed, and the stable operation of a subsequent system is ensured. The ultrafiltration inlet water is provided with a self-cleaning filter, so that the physical damage of the membrane caused by the leakage of a medium filter material is prevented. Ultrafiltration is a fluid tangential flow and pressure driven filtration process and separates particles by molecular weight. The pore size of the ultrafiltration membrane is approximately in the range of 0.002-0.1 micron. The dissolved substances and substances having a smaller pore size than the membrane permeate the membrane as a permeate, and the substances that do not permeate the membrane are concentrated in the effluent. Therefore, the produced water contains water, dissolved solids and small molecular weight substances, while colloids, suspended particles, high molecular weight organic matters, bacteria, viruses and protozoa are filtered and removed, and each set of ultrafiltration device can be independently overhauled in the process setting.

S6, 2) the water produced by the UF membrane filtering unit 213 enters an anion exchange resin unit 217 to further remove the inevitable elements such as nickel, cobalt and manganese in the water effluent, wherein the elements such as nickel, cobalt and manganese are about 1%, the anion exchange resin in the anion exchange resin unit 217 absorbs and exchanges negative ions of nickel, cobalt and manganese oxides to obtain hydroxides, the PH of the solution is correspondingly controlled to be increased to 8-9, so that the content of nickel, cobalt and manganese elements is further reduced to be below 0.5%, and the removal rate of nickel, cobalt and manganese by the anion exchange resin in the anion exchange resin unit 217 is above 90%.

The resin contains strong basic groups, such as quaternary ammonium groups (also called quaternary amino groups) -NR3OH (R is a hydrocarbon group), and can be dissociated into OH-in water to be strong in basic. The positively charged groups of the resin can be adsorbed to and combined with anions in solution, thereby generating anion exchange action. The resin has strong dissociation and can work normally under different pH values. It is regenerated with a strong base such as NaOH.

S7, 3) backwashing external drainage water generated by the UF membrane filtering unit 213 enters a backwashing external drainage tank 214, the backwashing external drainage water contains a small amount of lithium elements, in order to improve the recovery rate of lithium to the greatest extent, the backwashing external drainage water enters a lithium adsorption unit 215, the lithium elements can be adsorbed again in the adsorption process, then the lithium elements are separated out through clear water, the adsorption produced water lithium-containing solution enters an anion exchange resin unit 217, and is mixed with the water produced by the UF membrane filtering unit 213 and then enters the anion exchange resin unit 217 together for treatment, meanwhile, the regeneration drainage water of the lithium adsorption unit 215 has almost no lithium elements, the lithium content is below 0.1 percent, and the regeneration drainage water is discharged into a sewage station for treatment, and the water quality reaches the standard and then is discharged.

3. Extremely enhanced lithium concentration

1) Concentrating by multi-stage electrodialysis (as shown in FIG. 2)

Generally, a two-stage (or three-stage) concentration process is used, so that the recovery rate of the lithium metal can reach more than 95%.

S8, after being treated by the anion exchange resin unit 217, the lithium sulfate water with low concentration of 0.5-1.5g/L and high purity of 99.9% enters a raw water tank of the multistage electrodialysis concentration unit 31 and is stably conveyed into a first-stage desalting tank A11 through a first lifting pump A110.

Hundreds of anion and cation exchange membranes which are arranged in a staggered mode are arranged in an electrodialysis membrane stack of the multi-stage electrodialysis concentration unit 31, and partition plates are arranged in the middle of membranes, so that hundreds of chambers are formed. Anion exchange membranes allow only anions to pass through while retaining cations, and cation exchange membranes allow only cations to pass through while retaining anions.

After the multistage electrodialysis concentration unit 31 is automatically started, the first-stage desalination liquid circulation pump a12 configured in the multistage electrodialysis concentration unit 31 lifts the desalination liquid in the first-stage desalination tank a11 to the first channel (i.e., the desalination liquid inlet flow channel and the desalination liquid outlet flow channel) of the first-stage electrodialysis membrane stack a19 to circulate back to the first-stage desalination tank a11, which is a first circulation process.

The first-stage concentrate circulating pump a14 of the multi-stage electrodialysis concentration unit 31 lifts the concentrate in the first-stage concentration tank a13 to the second channel (i.e. the concentrate inlet channel and the concentrate outlet channel) of the first-stage electrodialysis membrane stack a19 to circulate back to the first-stage concentration tank a13, which is the second circulation process.

The first-stage catholyte circulating pump a16 and the first-stage anolyte circulating pump a18 of the multistage electrodialysis concentration unit 31 lift the polar liquids in the first-stage catholyte tank a15 and the first-stage anolyte tank a17 to the cathode and the anode (i.e., the cathode and anolyte inlet channels and the cathode and anolyte outlet channels) of the first-stage electrodialysis membrane stack a19 to circulate back to the first-stage catholyte tank a15 and the first-stage anolyte tank a17, which is a third circulation process.

After the direct current power supply of the multi-stage electrodialysis concentration unit 31 is output and connected to the first-stage electrodialysis membrane stack a19, the negative and positive salt ions in the desalted liquid in the first channel in the first circulation process migrate to the concentrated liquid side in the second channel in the second circulation process respectively under the action of the direct current power supply, and in the process of repeated circulation treatment, the salt in the raw water is removed, so that the salt in the concentrated liquid is continuously accumulated.

According to the principle, desalted water of the first-stage desalting tank A11 overflows into the second-stage desalting tank A21, concentrated water of the first-stage concentrating tank A13 overflows into the second-stage concentrating tank A23, the concentrated water enters the multi-stage electrodialysis concentrating unit 31 again for lithium extraction and enrichment, and after the concentrated water is extremely concentrated through two-stage (or three-stage) electrodialysis, the lithium content in mixed product water of two-stage concentrated liquid reaches over 22 g/L.

After the two-stage (or three-stage) electrodialysis extreme desalination, the lithium content of the desalted liquid is reduced to below 5%, the front end of the reflux is mixed with pure water flowing out of a pure water tank 29 and enters a water immersion liquid preparation tank 28, the mixture is mixed with the pure water to be used as a water immersion liquid to carry out water washing (water immersion) dissolution on a product after the lithium extraction section 5 of sulfating hydrogenation reduction roasting, the pH of the desalted liquid reflux water is high, and metals such as nickel and the like are more easily precipitated and removed in the form of hydroxide under the system by an alkali reagent.

The lithium is extracted and enriched by entering the multi-stage electrodialysis concentration unit 31 again as follows:

after the multistage electrodialysis concentration unit 31 is automatically started, the second-stage desalination liquid circulation pump a22 configured in the multistage electrodialysis concentration unit 31 lifts the desalination liquid in the second-stage desalination tank a21 to the first channel (i.e., the desalination liquid inlet flow channel and the desalination liquid outlet flow channel) of the second-stage electrodialysis membrane stack a29 to circulate back to the second-stage desalination tank a21, which is the first circulation process.

The second-stage concentrate circulating pump a24 of the multi-stage electrodialysis concentration unit 31 lifts the concentrate in the second-stage concentration tank a23 to the second channel (i.e. the concentrate inlet channel and the concentrate outlet channel) of the second-stage electrodialysis membrane stack a29 to circulate back to the second-stage concentration tank a23, which is the second circulation process.

The second-stage catholyte circulating pump a26 and the second-stage anolyte circulating pump a28 of the multistage electrodialysis concentration unit 31 lift the polar liquids in the second-stage catholyte tank a25 and the second-stage anolyte tank a27 to the cathode and the anode (i.e., the cathode and anolyte inlet channels and the cathode and anolyte outlet channels) of the second-stage electrodialysis membrane stack a29, and circulate back to the second-stage catholyte tank a25 and the second-stage anolyte tank a27, which is a third circulation process.

2) Chelate resin

S9, high-concentration (more than 22g/L of metallic lithium) and high-purity (99.9% of purity) lithium sulfate-rich concentrated water produced by the multistage electrodialysis concentration unit 31 enters a lithium sulfate-rich concentrated water tank 33, the lithium sulfate-rich concentrated water still contains a small amount of nickel, cobalt and manganese elements, and in order to improve the purity of lithium sulfate again, the lithium sulfate-rich concentrated water enters a raw water tank of a chelate resin unit 34 and then enters the chelate resin unit 34 through pump lifting to carry out deep nickel, cobalt and manganese element removal treatment.

The chelate resin is mainly reacted with metal ions in water to form a chelate which is insoluble in water, and then the chelate resin is settled at the bottom of the water under the action of gravity, thereby achieving the effect of separating water; the high and numerical precision are stable and reach the standard: the treatment precision is high, and the heavy metal content in the wastewater can be below 0.01 percent and is far lower than the national standard; the resin has large adsorption capacity, and the saturated adsorption capacity for nickel, cobalt and manganese can reach 56g/L; the module component form, the automation degree and the operation are simple; the production has strong continuous stability, reduces the cost of treating waste liquid, and simultaneously ensures the continuous and stable operation of the production.

The content of nickel, cobalt and manganese impurities in the produced water treated by the chelating resin unit 34 is reduced to be below 0.01%, and the high-purity lithium sulfate-rich concentrated water with the purity of more than 99.99% obtained in the high-purity lithium sulfate-rich concentrated water tank 36 can be used as a raw material liquid for final refined lithium extraction, so that the refined lithium extraction has multiple product directions.

4. Stage of refining product lithium

S10, 1) the lithium carbonate product direction (product direction 1), and the high-purity lithium sulfate-rich concentrated water enters a lithium carbonate product process production line, firstly enters a lithium precipitation conversion reaction unit 37, a conversion reagent sodium carbonate is added into the lithium carbonate conversion reaction unit to convert lithium sulfate into lithium carbonate, and carbonate is combined with lithium ions to form insoluble salt precipitation of the lithium carbonate after the sodium carbonate is dissolved in the process.

A large amount of water is removed by centrifugal separation in a lithium carbonate centrifugal separation disc type drying unit 41, and the lithium carbonate is dried, so that a battery grade lithium carbonate product with high value and purity of over 99.99 percent is produced.

The mother liquor containing a small amount of lithium after centrifugal separation enters a lithium adsorption unit 215 at the front end and is mixed with the drainage of a UF membrane filtration unit 213, and the recovery rate of lithium is improved.

S11 and 2) the product direction of lithium sulfate (product direction 2), directly feeding high-purity lithium sulfate-rich concentrated water into a MVR evaporation crystallization unit 42 for evaporation crystallization, and also producing a lithium sulfate solid salt product with the purity of 99.99%.

S12, 3) BP bipolar membrane electrodialysis-lithium hydroxide and sulfuric acid product direction (product direction 3, 4), and high-purity lithium sulfate-rich concentrated water can enter a BP bipolar membrane electrodialysis unit 39 for further treatment to prepare other high value-added products.

High-purity lithium sulfate-rich concentrated water enters an original water tank of a BP bipolar membrane electrodialysis unit 39 and is stably fed into a salt solution water tank B1 through a lifting pump B12, hundreds of anion-cation exchange membranes and bipolar membranes which are arranged in a staggered mode are arranged in an electrodialysis membrane stack of the BP bipolar membrane electrodialysis unit 39, and different cavity partition plates are arranged in the middle of each membrane and mainly comprise a salt chamber partition plate, a basic partition plate and an acid partition plate. Thus forming hundreds or thousands of chambers.

The bipolar membrane is a composite membrane, one side of the bipolar membrane can be electrolyzed to generate hydrogen ions, the other side of the bipolar membrane can be electrolyzed to generate hydroxide ions, and after the system is automatically started.

The salt solution circulating pump B2 configured in the BP bipolar membrane electrodialysis unit 39 lifts the high-purity lithium sulfate-rich concentrated water in the salt solution water tank B1 to the first channel (i.e., the salt solution water inlet flow channel and the salt solution water outlet flow channel) of the BP bipolar membrane electrodialysis membrane stack B11, and the first channel circulates back to the salt solution water tank B1, which is a first circulation process.

An acid liquor circulating pump B4 configured by the BP bipolar membrane electrodialysis unit 39 lifts the solution in the acid liquor water tank B3 to the second channel (i.e., the acid liquor inlet flow channel and the acid liquor outlet flow channel) of the BP bipolar membrane electrodialysis membrane stack B11, and the second channel circulates back to the acid liquor water tank B3, which is a second circulation process.

An alkali liquor circulating pump B6 configured by the BP bipolar membrane electrodialysis unit 39 lifts the solution in the alkali liquor water tank B5 to a third channel (namely an alkali liquor inlet flow channel and an alkali liquor outlet flow channel) of the BP bipolar membrane electrodialysis membrane stack B11, and the third channel is circulated back to the alkali liquor water tank B5, which is a third circulation process.

The catholyte circulating pump B8 and the anolyte circulating pump B10 configured in the BP bipolar membrane electrodialysis unit 39 lift the catholyte in the catholyte tank B7 and the anolyte tank B9 to the cathode and the anode (i.e., the cathode and anolyte inlet channels and the cathode and anolyte outlet channels) in the BP bipolar membrane electrodialysis membrane stack B11, and circulate back to the catholyte circulating pump B8 and the anolyte circulating pump B10, which is the fourth circulation process.

After the direct-current power supply configured by the BP bipolar membrane electrodialysis unit 39 outputs and is connected to the BP bipolar membrane electrodialysis membrane stack B11, under the action of the direct-current power supply, anions (sulfate radicals) in the salt solution in the first circulation process migrate to the second channel in the second circulation process, and cations (lithium elements) migrate to the third channel in the third circulation process.

(1) In the process of repeated circulation treatment, the concentration of lithium sulfate in the salt solution is reduced, when the concentration of lithium is controlled to be about 5%, low-purity lithium sulfate mother solution is formed in the low-purity lithium sulfate mother solution box 35, the low-purity lithium sulfate mother solution flows back to the front end of the multistage electrodialysis concentration unit 31 and is mixed with the lithium-rich solution in the anion exchange resin unit 217, and the recovery rate of metal lithium is improved.

(2) In the process of repeated circulation treatment, the concentration of sulfuric acid in the acid solution is increased more and more, and the sulfuric acid solution can reach a dilute sulfuric acid solution with the purity of 99.99 percent and the concentration of 10-12 percent, can flow back to a dilute sulfuric acid preparation pool 23 at the front end to be mixed with concentrated sulfuric acid to prepare dilute sulfuric acid with the concentration of 40-50 percent, and can be used as a washing solution for extracting lithium by sulfation hydrogenation reduction roasting, or can be packaged for sale.

(3) In the process of repeated cycle treatment, the concentration of lithium hydroxide in the alkali liquor is increased more and more, the solution with the concentration of lithium hydroxide with the purity of 10-15% and the purity of 99.99% can be obtained and enter a second lithium hydroxide solution tank 43, and the alkaline lithium hydroxide solution can be partially conveyed to a front-end lithium adsorption unit 215 to adjust the pH value of the mixture of the electrodialysis desalination solution and pure water to 11-12, so that metals such as nickel and the like are precipitated and recovered in the form of hydroxide during water leaching, and the removal rate is increased.

The high-purity lithium hydroxide solution is evaporated, concentrated and crystallized by a second MVR evaporation and crystallization unit 44 to obtain 99.99 percent of high-purity high-additional-value battery pole lithium hydroxide solid salt product.

1) By matching the processes and controlling the operation parameters, the recovery rate of the lithium element can reach more than 99.9 percent, and the purity can reach more than 99.99 percent.

2) The concentration of the lithium ions is increased from 0.5-1.5g/L to more than 15-20 g/L.

3) The method comprises the steps of refluxing, mixing and refluxing a lithium hydroxide alkaline solution produced by a back-end BP bipolar membrane electrodialysis unit and an electrodialysis desalination solution to flow back into a water immersion solution preparation pool, mixing and preparing the water immersion solution into pure water, and controlling the ph to be 11-12, so that about 5% of nickel, cobalt and manganese in a lithium sulfate solution after water immersion can be removed, and the content of nickel, cobalt and manganese in the lithium sulfate solution after water immersion is reduced to about 1-2%.

4) Sulfuric acid produced by the BP bipolar membrane electrodialysis unit is recycled for the front end sulfating, reducing, roasting and lithium extracting section, and dilute sulfuric acid is used for diluting concentrated sulfuric acid, so that the concentration of the sulfuric acid is controlled to be 40-50%, the consumption of the front end sulfuric acid is greatly reduced, and the consumption of diluted pure water is also reduced.

5) UF ultrafiltration backwash water and sodium carbonate centrifugal mother liquor are mixed and enter an adsorption system to carry out lithium element recovery treatment again, and the improved recovery rate of metal lithium is greatly facilitated.

6) Obtaining a battery-grade lithium carbonate product with the purity of more than 99.99 percent, obtaining a battery-grade lithium hydroxide product with the purity of more than 99.99 percent, obtaining a lithium sulfate product with the purity of more than 99.99 percent, and obtaining a high-purity sulfuric acid product with the concentration of 8-10 percent.

7) And (3) preparing acid and alkali by using bipolar membrane electrodialysis, and refluxing the lithium-containing salt solution to the front end of the multistage ED electrodialysis system to be mixed with the lithium-rich solution of the anion exchange resin when the concentration of the lithium-containing salt solution is controlled to be about 5%, so that the recovery rate of the metallic lithium is improved.

The noun interpretation:

a: anion exchange membrane, C: cation exchange membrane, BP: bipolar membrane, li ⁺ : lithium ion, SO ₄ ^2- : sulfate ion, H ^- : hydrogen ions.

In addition, it should be noted that the specific embodiments described in the present specification may be different in the components, the shapes of the components, the names of the components, and the like, and the above description is only an example of the structure of the present invention. All the foundation the utility model discloses an all include in the protection scope of the utility model discloses an equivalent change or simple change that structure, characteristic and principle do. Those skilled in the art can modify or supplement the described embodiments or substitute them in a similar manner without departing from the scope of the invention as defined by the claims.

Claims

1. A system for recycling ternary lithium batteries to prepare lithium sulfate, lithium carbonate and lithium hydroxide comprises a first stage (1), a second stage (2), a third stage (3) and a fourth stage (4), wherein the first stage (1) comprises a crushing separator (11), a combustion device (12) and a residue pond (13), and the second stage (2) comprises a black powder pond (21), a mixer (22), a dilute sulfuric acid preparation pond (23), a rotary kiln (24), a hydrogen pond (25), a steam tail gas treatment unit (26), a water leaching pond (27), a water leaching solution preparation pond (28), a pure water tank (29), a first lithium hydroxide solution pond (210), a lithium-containing raw solution pond (211), a nickel-cobalt-manganese dry residue raw material pond (212), a UF membrane filtration unit (213), a backwashing outer liquid discharge pond (214), a lithium adsorption unit (215), a lithium carbonate centrifugal separation dry mother solution pond (216) and an anion exchange resin unit (217);

the crushing separator (11) is respectively connected with a combustion device (12), a residue pool (13) and a black powder pool (21), the black powder pool (21) and a dilute sulfuric acid configuration pool (23) are respectively connected with a mixer (22), the mixer (22) and a hydrogen pool (25) are respectively connected with a rotary kiln (24), the rotary kiln (24) is respectively connected with a steam tail gas treatment unit (26) and a water immersion pool (27), the water immersion pool (28) is connected with the water immersion pool (27), a pure water tank (29) is connected with the water immersion pool (28), the water immersion pool (27) is connected with a lithium-containing stock solution pool (211), the lithium-containing stock solution pool (211) is respectively connected with a nickel-cobalt-manganese dry residue stock pool (212) and a UF membrane filtration unit (213), the UF membrane filtration unit (213) is respectively connected with a backwash external liquid discharge pool (214) and an anion exchange resin unit (217), the lithium external adsorption unit (215) is connected with a lithium ion adsorption unit (215), and a lithium ion exchange resin centrifugal lithium ion exchange unit (217) is respectively connected with a lithium ion exchange unit (215),

the method is characterized in that: the third stage (3) comprises a multi-stage electrodialysis concentration unit (31), an electrodialysis desalination liquid tank (32), a lithium sulfate rich concentrated water tank (33), a chelating resin unit (34), a low-purity lithium sulfate mother liquid tank (35), a high-purity lithium sulfate rich concentrated water tank (36), a lithium deposition conversion reaction unit (37), a sodium carbonate soda unit (38) and a BP bipolar membrane electrodialysis unit (39), and the fourth stage (4) comprises a lithium carbonate centrifugal separation disc type drying unit (41), a first MVR evaporation crystallization unit (42), a second lithium hydroxide solution tank (43) and a second MVR evaporation crystallization unit (44);

anion exchange resin unit (217) is connected with multistage electrodialysis concentration unit (31), multistage electrodialysis concentration unit (31) is connected with electrodialysis desalination liquid case (32) and lithium sulfate rich concentrated water tank (33) respectively, electrodialysis desalination liquid case (32) is connected with water immersion liquid configuration pool (28), pipeline connection between lithium hydroxide solution pool (210) and electrodialysis desalination liquid case (32) and water immersion liquid configuration pool (28), lithium sulfate rich concentrated water tank (33) is connected with chelate resin unit (34), chelate resin unit (34) is connected with high-purity lithium sulfate rich concentrated water tank (36), high-purity lithium sulfate rich concentrated water tank (36) is connected with lithium deposition conversion reaction unit (37), BP bipolar membrane electrodialysis unit (39) and MVR evaporative crystallization unit (42) respectively, soda ash unit (38) is connected with lithium deposition conversion reaction unit (37), lithium deposition conversion reaction unit (37) is connected with lithium carbonate centrifugal separation drying unit (41), centrifugal separation drying unit (217) is connected with lithium sulfate ion exchange resin unit (35), lithium sulfate concentrate solution tank (41) is connected with lithium sulfate concentrate tank (35), lithium carbonate ion adsorption drying unit (41) is connected with lithium sulfate concentrate tank (35) and lithium sulfate concentrate tank (35) is connected with lithium carbonate low-lithium hydroxide solution adsorption unit (41), lithium carbonate ion adsorption drying unit (35) and lithium ion adsorption unit (35) is connected with lithium sulfate concentrate tank (35) and lithium ion adsorption tank (23) and lithium sulfate concentrate tank (35) respectively And the second lithium hydroxide solution tank (43) is respectively connected with the second MVR evaporation crystallization unit (44) and the water immersion liquid preparation tank (28).

2. The system for recycling lithium sulfate, lithium carbonate and lithium hydroxide for the ternary lithium battery as claimed in claim 1, wherein: the mixer (22), the dilute sulfuric acid preparation pool (23), the rotary kiln (24), the hydrogen pool (25) and the steam tail gas treatment unit (26) form a sulfating hydrogenation reduction roasting lithium extraction section, and the water immersion pool (27), the water immersion liquid preparation pool (28), the pure water tank (29), the first lithium hydroxide solution pool (210), the lithium-containing stock solution pool (211) and the nickel-cobalt-manganese dry slag stock pool (212) form a water immersion section.

3. The system for preparing lithium sulfate, lithium carbonate and lithium hydroxide by recycling the ternary lithium battery as claimed in claim 1, wherein: the first stage (1) is a stage of sorting and extracting black powder, the second stage (2) is a stage of pretreatment impurity removal, the third stage (3) is a stage of extremely-intensive lithium extraction concentration, and the fourth stage (4) is a stage of refined lithium products.

4. The system for preparing lithium sulfate, lithium carbonate and lithium hydroxide by recycling the ternary lithium battery as claimed in claim 1, wherein: the multistage electrodialysis concentration unit (31) comprises a first-stage electrodialysis concentration unit (A1) and a second-stage electrodialysis concentration unit (A2), the first-stage electrodialysis concentration unit (A1) comprises a first-stage desalting tank (A11), a first-stage desalting liquid circulating pump (A12), a first-stage concentration tank (A13), a first-stage concentrating liquid circulating pump (A14), a first-stage cathode liquid tank (A15), a first-stage cathode liquid circulating pump (A16), a first-stage anode liquid tank (A17), a first-stage anode liquid circulating pump (A18) and a first-stage electrodialysis membrane stack (A19), and the second-stage electrodialysis concentration unit (A2) comprises a second-stage desalting tank (A21), a second-stage desalting liquid circulating pump (A22), a second-stage concentration tank (A23), a second-stage concentrating liquid circulating pump (A24), a second-stage cathode liquid tank (A25), a second-stage cathode liquid circulating pump (A26), a second-stage anode liquid tank (A27), a second-stage anode liquid circulating pump (A28) and a second-stage electrodialysis membrane stack (A29);

the first channels of the first-stage desalting tank (A11), the first-stage desalting solution circulating pump (A12) and the first-stage electrodialysis membrane stack (A19) are sequentially and circularly connected and form the first circulation of the first-stage electrodialysis concentration unit (A1), the second channels of the first-stage concentrating tank (A13), the first-stage concentrating solution circulating pump (A14) and the first-stage electrodialysis membrane stack (A19) are sequentially and circularly connected and form the second circulation of the first-stage electrodialysis concentration unit (A1), the cathodes of the first-stage cathode solution tank (A15), the first-stage cathode solution circulating pump (A16) and the first-stage electrodialysis membrane stack (A19) are sequentially and circularly connected and form the third circulation of the first-stage electrodialysis concentration unit (A1), the anodes of the first-stage anode solution tank (A17), the first-stage anode solution circulating pump (A18) and the first-stage electrodialysis membrane stack (A19) are sequentially and circularly connected and form the third circulation of the first-stage electrodialysis concentration unit (A1),

the utility model discloses a desalination device, including one-level desalination case (A11) and one-level concentration case (A13), the first passageway of second grade desalination case (A21) and second grade concentration case (A23) are connected with second grade desalination case (A21) and second grade concentration case (A23) respectively, second grade desalination case (A21), second grade desalination liquid circulating pump (A22) and second grade electrodialysis membrane stack (A29) is circulation connection in proper order to form the first circulation of second grade electrodialysis concentration unit (A2), the second passageway of second grade concentration case (A23), second grade concentration liquid circulating pump (A24) and second grade electrodialysis membrane stack (A29) is circulation connection in proper order to form the second circulation of second grade electrodialysis concentration unit (A2), the negative pole of second grade cathode liquid case (A25), second grade cathode liquid circulating pump (A26) and second grade electrodialysis membrane stack (A29) is circulation connection in proper order to form the third circulation of second grade electrodialysis concentration unit (A2), the second grade anode liquid case (A27), second grade cathode liquid circulating pump (A28) and the anode membrane stack (A29) of second grade electrodialysis are circulation connection in proper order to form the third circulation of second grade electrodialysis concentration unit (A2).

5. The system for preparing lithium sulfate, lithium carbonate and lithium hydroxide by recycling the ternary lithium battery as claimed in claim 4, wherein: concentrated unit of one-level electrodialysis (A1) still includes elevator pump (A110) and No. two elevator pumps (A111), the former water tank of concentrated unit of multistage electrodialysis (31) is connected with elevator pump (A110), elevator pump (A110) is connected with one-level desalination case (A11), the former water tank of one-level concentration case (A13) and chelate resin unit (34) is connected, the former water tank of chelate resin unit (34) is connected with No. two elevator pumps (A111).

6. The system for preparing lithium sulfate, lithium carbonate and lithium hydroxide by recycling the ternary lithium battery as claimed in claim 4, wherein: in the first-stage electrodialysis membrane stack (A19), the anion exchange membrane (A) and the cation exchange membrane (C) are both positioned between the cathode and the anode, a first channel or a second channel is formed between the adjacent anion exchange membrane (A) and the adjacent cation exchange membrane (C), in the second-stage electrodialysis membrane stack (A29), the anion exchange membrane (A) and the cation exchange membrane (C) are both positioned between the cathode and the anode, a first channel or a second channel is formed between the adjacent anion exchange membrane (A) and the adjacent cation exchange membrane (C), the first channel is a desalted liquid channel, and the second channel is a concentrated liquid channel.

7. The system for preparing lithium sulfate, lithium carbonate and lithium hydroxide by recycling the ternary lithium battery as claimed in claim 1, wherein: the BP bipolar membrane electrodialysis unit (39) comprises a salt solution water tank (B1), a salt solution circulating pump (B2), an acid solution water tank (B3), an acid solution circulating pump (B4), an alkali solution water tank (B5), an alkali solution circulating pump (B6), a cathode solution tank (B7), a cathode solution circulating pump (B8), an anode solution tank (B9), an anode solution circulating pump (B10) and a BP bipolar membrane electrodialysis membrane stack (B11),

the first channels of the salt solution water tank (B1), the salt solution circulating pump (B2) and the BP bipolar membrane electrodialysis membrane stack (B11) are sequentially and circularly connected and form a first circulation of the BP bipolar membrane electrodialysis membrane stack (B11), the second channels of the acid solution water tank (B3), the acid solution circulating pump (B4) and the BP bipolar membrane electrodialysis membrane stack (B11) are sequentially and circularly connected and form a second circulation of the BP bipolar membrane electrodialysis membrane stack (B11), the third channels of the alkali solution water tank (B5), the alkali solution circulating pump (B6) and the BP bipolar membrane electrodialysis membrane stack (B11) are sequentially and circularly connected, and a third circulation of the BP bipolar membrane electrodialysis membrane stack (B11) is formed, the cathodes of the cathode liquid tank (B7), the cathode liquid circulating pump (B8) and the BP bipolar membrane electrodialysis membrane stack (B11) are sequentially and circularly connected, and a fourth circulation of the BP bipolar membrane electrodialysis membrane stack (B11) is formed, and the anodes of the anode liquid tank (B9), the anode liquid circulating pump (B10) and the BP bipolar membrane electrodialysis membrane stack (B11) are sequentially and circularly connected, and a fourth circulation of the BP bipolar membrane electrodialysis membrane stack (B11) is formed.

8. The system for recycling lithium sulfate, lithium carbonate and lithium hydroxide for the ternary lithium battery as claimed in claim 7, wherein: the BP bipolar membrane electrodialysis unit (39) further comprises a lift pump (B12), a raw water tank of the BP bipolar membrane electrodialysis unit (39) is connected with the lift pump (B12), the lift pump (B12) is connected with a salt solution water tank (B1), an acid solution water tank (B3) is connected with a dilute sulfuric acid preparation tank (23), and an alkali solution water tank (B5) is respectively connected with a water immersion solution preparation tank (28) and a second MVR evaporation crystallization unit (44).

9. The system for recycling lithium sulfate, lithium carbonate and lithium hydroxide for the ternary lithium battery as claimed in claim 7, wherein: in the BP bipolar membrane electrodialysis membrane stack (B11), an anion exchange membrane (A), a cation exchange membrane (C) and a bipolar membrane (BP) are all located between a cathode and an anode, a first channel is formed between the cation exchange membrane (C) and the anion exchange membrane (A), a second channel is formed between the anion exchange membrane (A) and the anode of the bipolar membrane (BP), a third channel is formed between the cathode of the bipolar membrane (BP) and the cation exchange membrane (C), the first channel is a salt solution channel, the second channel is an acid solution channel, and the third channel is an alkali solution channel.