A device for recycling and processing electrolyte of waste lithium battery

Abstract

The application provides a kind of old lithium battery electrolyte recovery processing device, including extraction transmission system, extraction kettle and separation kettle, extraction transmission system, extraction kettle and separation kettle are connected into a closed loop by pipeline, the top of extraction kettle is equipped with a crushing mechanism with crushing cavity, and extraction kettle and crushing cavity are closed communication;Wherein, extraction transmission system is used to transport CO2 and carrying agent into extraction kettle simultaneously;Crushing mechanism is used for crushing treatment to old lithium battery;Extraction kettle is used to make CO2 in supercritical state, and the electrolyte in old lithium battery after crushing treatment is extracted to obtain extraction phase and raffinate phase;Separation kettle is used to separate electrolyte extractant in extraction phase;The old lithium battery electrolyte recovery processing device provided by the application can automatically recover and process the electrolyte in old lithium battery, has no secondary pollution to the environment, no solvent residue, good product reduction degree, and effectively improves the recovery efficiency.

Description

Technical Field

[0001] This invention relates to the field of lithium-ion battery recycling technology, and in particular to a device for recycling and processing waste lithium battery electrolyte. Background Technology

[0002] Current research and industrial applications of recycled lithium-ion batteries mainly focus on recovering the high-value active materials in the cathode. Research on electrolyte recycling is scarce, resulting in virtually no industrial applications. However, electrolytes are volatile and produce unpleasant odors. Furthermore, the hydrolysis of lithium salts in the electrolyte produces toxic arsenic compounds, phosphides, and fluorides, posing significant health and environmental hazards. This has become an unavoidable problem, as the electrolyte accounts for approximately 12% of the total battery cost. Therefore, electrolyte recycling is of great importance from both economic and environmental perspectives.

[0003] There are three main methods for recycling electrolyte from spent lithium-ion batteries: high-temperature pyrolysis, distillation-condensation, and chemical methods. High-temperature pyrolysis involves calcining spent lithium-ion batteries at high temperatures. This method is simple, has a large processing capacity, and is suitable for various types of spent lithium-ion batteries. However, the resulting exhaust gas contains harmful substances such as fluorides, requiring specialized exhaust gas treatment equipment in actual production, increasing subsequent processing costs. Furthermore, the electrolyte, after high-temperature pyrolysis and subsequent condensation, has undergone thermal decomposition and has no recycling value. Distillation-condensation can efficiently and easily recover electrolyte from spent lithium-ion batteries, offering advantages such as low cost, ease of control, and cleanliness. However, the lithium salts in the electrolyte are non-volatile and cannot be effectively recovered, and the solvent recovery rate is low. Chemical methods offer high lithium salt recovery rates from spent lithium-ion battery electrolytes, but low solvent recovery rates. Since this process involves additional chemical reagents, these may be harmful to the environment and increase recycling costs.

[0004] In summary, existing technologies treat residual waste lithium battery materials through pyrometallurgical processes and high-temperature pyrolysis. The residual electrolyte is often vaporized and discharged, which not only wastes the electrolyte but also causes serious environmental pollution and does not meet the requirements for full recycling. Summary of the Invention

[0005] The purpose of this invention is to provide a recycling and processing device for waste lithium battery electrolyte, which improves the technical problem that existing recycling and processing devices cannot automate and harmlessly recycle waste lithium battery electrolyte.

[0006] To solve the above-mentioned technical problems, the present invention provides a recycling and processing device for waste lithium battery electrolyte, including an extraction and transmission system, an extraction vessel, and a separation vessel. The extraction and transmission system, the extraction vessel, and the separation vessel are connected to form a closed loop through pipelines. A crushing mechanism with a crushing chamber is installed on the top of the extraction vessel, and the cavity inside the extraction vessel and the crushing chamber can be closedly connected. The extraction and transfer system is used to simultaneously deliver CO2 and carrier into the extraction vessel; the crushing mechanism is used to crush the waste lithium batteries; the extraction vessel is used to make CO2 supercritical and to extract the electrolyte in the crushed waste lithium batteries to obtain the extract phase and the raffinate phase; the separation vessel is used to separate the electrolyte extract from the extract phase.

[0007] Preferably, a first connecting shaft is provided inside the crushing chamber, one end of the first connecting shaft passes through the crushing chamber and is fixedly connected to the first drive motor, and a first gear and a first crushing roller spaced apart from the first gear are also fixedly sleeved on the first connecting shaft; The crushing chamber is also equipped with a second connecting shaft, on which a second gear and a second crushing roller spaced apart are fixedly sleeved. The second gear meshes with the first gear.

[0008] Preferably, the outer walls of both the first crushing roller and the second crushing roller are fixed with multiple crushing teeth.

[0009] Preferably, the bottom plate of the crushing mechanism near the extraction vessel has a feed inlet, and a first solenoid valve and a second solenoid valve are fixedly installed at the two ends of the bottom plate near the feed inlet, respectively. A first telescopic spring is fixedly installed on the side of the first solenoid valve away from the bottom plate, and a second telescopic spring is fixedly installed on the side of the second solenoid valve away from the bottom plate. The crushing mechanism also includes a feed baffle, with a first iron block and a second iron block fixedly installed at both ends of the feed baffle; the first iron block is fixedly connected to a first telescopic spring, and the second iron block is fixedly connected to a second telescopic spring.

[0010] Preferably, the crushing mechanism is further provided with a first baffle and a second baffle that are spaced apart on the side near the extraction vessel. One end of the first baffle is fixedly connected to the inner wall of one side of the crushing mechanism, and the other end of the first baffle passes through the feed inlet and is integrally formed with the shell of the extraction vessel. One end of the second baffle is fixedly connected to the inner wall of the other side of the crushing mechanism, and the other end of the second baffle passes through the feed inlet and is integrally formed with the shell of the extraction vessel. The first baffle has a first through hole, the second baffle has a second through hole, and the feed baffle passes through the first through hole and the second through hole respectively; the length of the feed baffle is greater than the minimum distance between the first baffle and the second baffle.

[0011] Preferably, an automatic discharge mechanism is fixedly installed on the side of the extraction vessel away from the crushing mechanism. The discharge chamber of the automatic discharge mechanism can be closed and connected with the chamber inside the extraction vessel. The automatic discharge mechanism includes a discharge plug, a third connecting shaft, a fixing block, and a second drive motor. The feed plug is threaded onto the inner wall of the discharge chamber, and the fixing block is fixedly connected to the bottom of the discharge chamber. One end of the third connecting shaft passes through the feed plug and extends into the cavity of the extraction vessel, while the other end of the third connecting shaft passes through the fixing block and is fixedly connected to the second drive motor on the outside of the discharge chamber.

[0012] Preferably, the side wall of the discharge cavity is provided with a discharge groove, and multiple levers are fixedly installed on the outer side wall of the third connecting shaft.

[0013] Preferably, the extraction and transmission system includes a CO2 transmission pipeline and a carrier transmission pipeline. The CO2 transmission pipeline includes a CO2 storage tank, a purifier, a refrigerator, and a CO2 pump connected in sequence through the pipeline. The carrier transmission pipeline includes a carrier storage tank and a carrier pump connected in sequence through the pipeline. The extraction transfer system also includes a mixer, the first end of which is connected to a CO2 pump via a first pipeline, and the first end of which is also connected to a carrier pump via a second pipeline; the second end of which is connected to the extraction vessel via a third pipeline.

[0014] Preferably, the extraction vessel and the separation vessel are connected by a fourth pipeline, on which a first valve, a second valve and a third valve are installed. The second valve is connected in series with the first valve, and the third valve is connected in parallel with the second valve. The extraction transmission system and the separation vessel are connected by a fifth pipeline, on which a fourth valve, a fifth valve and a sixth valve are installed. The fifth valve is connected in series with the fourth valve, and the sixth valve is connected in parallel with the fifth valve. The second and fifth valves are both fine-tuning valves.

[0015] Preferably, a first pressure sensor and a first temperature sensor are respectively installed on the outer wall of the extraction vessel shell, and a second pressure sensor and a second temperature sensor are respectively installed on the outer wall of the separation vessel shell.

[0016] The beneficial effects of this invention are as follows: Unlike existing technologies, this invention provides a recycling and processing device for waste lithium battery electrolyte, including an extraction and transmission system, an extraction vessel, and a separation vessel. The extraction and transmission system, the extraction vessel, and the separation vessel are connected in a closed loop via pipelines. A crushing mechanism with a crushing chamber is installed on the top of the extraction vessel, and the extraction vessel and the cavity within the crushing chamber are in closed communication. The extraction and transmission system simultaneously delivers CO2 and a carrier to the extraction vessel; the crushing mechanism crushes the waste lithium batteries; and the extraction vessel brings the CO2 to a supercritical state and processes the crushed... The electrolyte in the treated waste lithium batteries is extracted to obtain an extract phase and a raffinate phase; a separation vessel is used to separate the electrolyte extract from the extract phase; the waste lithium battery electrolyte recycling device provided by the present invention uses supercritical CO2 in the extraction vessel to extract the crushed waste lithium batteries to obtain an extract phase, and collects the electrolyte extract from the extract phase in the separation vessel. This recycling device can automatically recycle the electrolyte in waste lithium batteries, with no secondary pollution to the environment, no solvent residue, good product reduction, and effectively improves recycling efficiency. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of the waste lithium battery electrolyte recycling and processing device provided in an embodiment of the present invention; Figure 2 yes Figure 1 An enlarged schematic diagram of the waste lithium battery electrolyte recycling and processing device at point A; Figure 3 yes Figure 1 An enlarged schematic diagram of the waste lithium battery electrolyte recycling and processing device at point A; Figure 4 yes Figure 1 An enlarged schematic diagram of the waste lithium battery electrolyte recycling and processing device at point B. Detailed Implementation

[0018] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0019] The technical solution of this application will now be described in conjunction with specific embodiments.

[0020] Please see Figures 1 to 4 , Figure 1 This is a schematic diagram of the overall structure of the waste lithium battery electrolyte recycling and processing device provided in an embodiment of the present invention; Figure 2 yes Figure 1 A schematic diagram of the crushing mechanism 80 in the waste lithium battery electrolyte recycling and processing device; Figure 3 yes Figure 1 An enlarged schematic diagram of the waste lithium battery electrolyte recycling and processing device at point A; Figure 4 yes Figure 1 An enlarged schematic diagram of the waste lithium battery electrolyte recycling and processing device at point B.

[0021] Specifically, please refer to Figure 1 The present invention provides a recycling and processing device for waste lithium battery electrolyte, including an extraction and transmission system, an extraction vessel 90 and a separation vessel 100. The extraction and transmission system, the extraction vessel 90 and the separation vessel 100 are connected to form a closed loop through pipelines. A crushing mechanism 80 with a crushing chamber is installed on the top of the extraction vessel 90. The cavity inside the extraction vessel 90 and the crushing chamber can be closedly connected. The extraction and transfer system is used to simultaneously deliver CO2 and carrier to the extraction vessel 90; the crushing mechanism 80 is used to crush the waste lithium batteries; the extraction vessel 90 is used to make CO2 supercritical and to extract the electrolyte in the crushed waste lithium batteries to obtain the extract phase and the raffinate phase; the separation vessel 100 is used to separate the electrolyte extract from the extract phase.

[0022] Please see Figure 1 as well as Figure 2 A first connecting shaft 82 is provided inside the crushing chamber. One end of the first connecting shaft 82 passes through the crushing chamber and is fixedly connected to the first drive motor 81. A first gear 84 and a first crushing roller 86 spaced apart from the first gear 84 are also fixedly sleeved on the first connecting shaft 82. The crushing chamber is also equipped with a second connecting shaft 83, on which a second gear 85 and a second crushing roller 87 are fixedly sleeved. The second gear 85 meshes with the first gear 84.

[0023] Specifically, the first drive motor 81 drives the first connecting shaft 82 to rotate, and the first connecting shaft 82 drives the first gear 84 and the first crushing roller 86 to rotate coaxially; at the same time, the first gear 84 drives the second gear 85 to rotate, and the second gear 85 drives the second connecting shaft 83 and the second crushing roller 87 to rotate coaxially, thereby enabling the first crushing roller 86 and the second crushing roller 87 to crush waste lithium batteries.

[0024] Preferably, the outer walls of both the first crushing roller 86 and the second crushing roller 87 are fixed with multiple crushing teeth. The crushing teeth enable further crushing of the waste lithium batteries to separate the electrolyte and electrode plates from the waste lithium batteries.

[0025] Please see Figure 1 as well as Figure 3 The bottom plate of the crushing mechanism 80 near the extraction vessel 90 has a feed inlet. The bottom plate near the feed inlet is fixedly installed with a first solenoid valve 891 and a second solenoid valve 892 respectively. The first solenoid valve 891 is fixedly installed with a first telescopic spring 8101 on the side away from the bottom plate, and the second solenoid valve 892 is fixedly installed with a second telescopic spring 8102 on the side away from the bottom plate. The crushing mechanism 80 also includes a feed baffle 812, with a first iron block 8111 and a second iron block 8112 fixedly installed at both ends of the feed baffle 812; the first iron block 8111 is fixedly connected to the first telescopic spring 8101, and the second iron block 8112 is fixedly connected to the second telescopic spring 8102.

[0026] Specifically, the crushing mechanism 80 is provided with a first baffle 881 and a second baffle 882 arranged at intervals on the side near the extraction vessel 90. One end of the first baffle 881 is fixedly connected to the inner wall of one side of the crushing mechanism 80, and the other end of the first baffle 881 passes through the feed inlet and is integrally formed with the shell of the extraction vessel 90. One end of the second baffle 882 is fixedly connected to the inner wall of the other side of the crushing mechanism 80, and the other end of the second baffle 882 passes through the feed inlet and is integrally formed with the shell of the extraction vessel 90. The first baffle 881 has a first through hole, the second baffle 882 has a second through hole, and the feed partition 812 passes through the first through hole and the second through hole respectively; the length of the feed partition 812 is greater than the minimum distance between the first baffle 881 and the second baffle 882.

[0027] Furthermore, when the first solenoid valve 891 is opened, the first iron block 8111 moves towards the first solenoid valve 891 under the action of magnetic force, the first telescopic spring 8101 contracts, and the feed baffle 812 moves towards the first solenoid valve 891 accordingly, opening the feed port. The waste electrolytic cell after crushing enters the extraction vessel 90 through the feed port. When the second solenoid valve 892 is opened, the second iron block 8112 moves towards the second solenoid valve 892 under the action of magnetic force, the second telescopic spring 8102 contracts, and the feed baffle 812 moves towards the second solenoid valve 892 accordingly, opening the feed port. The waste electrolytic cell after crushing enters the extraction vessel 90 through the feed port.

[0028] Please see Figure 1 as well as Figure 4 An automatic discharge mechanism is fixedly installed on the side of the extraction vessel 90 away from the crushing mechanism 80. The discharge chamber of the automatic discharge mechanism can be closed and connected with the discharge port 93 of the extraction vessel 90. The automatic discharge mechanism includes a discharge plug 96, a third connecting shaft 95, a fixing block 98, and a second drive motor 94. The feeding plug 96 is used to block the feeding port 93. The feeding plug 96 is threaded to the inner wall of the discharge cavity, and the fixing block 98 is fixedly connected to the bottom of the discharge cavity. One end of the third connecting shaft 95 passes through the feeding plug 96 and extends into the cavity of the extraction vessel 90. The other end of the third connecting shaft 95 passes through the fixing block 98 and is fixedly connected to the second drive motor 94 on the outside of the discharge cavity.

[0029] Specifically, the second drive motor 94 can control the rotation direction of the third connecting shaft 95; when the second drive motor 94 drives the third connecting shaft 95 to rotate clockwise, the third connecting shaft 95 drives the feed plug 96 to tighten, the discharge chamber is not connected to the extraction vessel 90, and the feed port at the top of the discharge chamber is in a closed state; when the second drive motor 94 drives the third connecting shaft 95 to rotate counterclockwise, the third connecting shaft 95 drives the feed plug 96 to loosen, the discharge chamber is connected to the extraction vessel 90, the feed port at the top of the discharge chamber is in an open state, and the raffinate in the extraction vessel 90 falls with gravity.

[0030] Preferably, a discharge trough 99 is provided on the side wall of the discharge chamber, and the discharge trough 99 is set at an acute angle with the discharge chamber. Multiple levers 97 are fixedly installed on the outer side wall of the third connecting shaft 95. The purpose of setting the levers 97 is to make the residual phase (mostly solid) fall under the action of gravity while playing a stirring role, which helps the residual phase to be discharged from the discharge trough 99 and avoids the accumulation of residual phase blocking the discharge port; Preferably, the fixing block 98 is a fixing and sealing block, with the top end of the fixing block 98 flush with the bottom end of the feeding trough 99, to prevent the residual phase from depositing at the bottom of the discharge cavity.

[0031] Please continue reading. Figure 1 The extraction and transmission system includes a CO2 transmission pipeline and a carrier transmission pipeline. The CO2 transmission pipeline includes a CO2 storage tank 10, a purifier 20, a refrigerator 30 and a CO2 pump 40 connected in sequence through the pipeline. The carrier transmission pipeline includes a carrier storage tank 50 and a carrier pump 60 connected in sequence through the pipeline. The extraction transfer system also includes a mixer 70, the first end of which is connected to the CO2 pump 40 via a first pipeline, and the first end of the mixer 70 is also connected to the carrier pump 60 via a second pipeline; the second end of the mixer 70 is connected to the extraction vessel 90 via a third pipeline.

[0032] Specifically, the mixer 70 is used to fully mix CO2 with the carrier; the CO2 storage tank 10 is used to provide CO2; the purifier 20 is used to purify the toxic gases generated during the extraction of waste battery electrolyte; and the refrigerator 30 is used to cool and liquefy the CO2 gas, with a refrigeration temperature range of 4 to 8°C.

[0033] Specifically, the carrier tank 50 is used to provide a carrier, which includes any one of ethanol, acetone, propylene carbonate, N,N-dimethylformamide, and γ-butyrolactone.

[0034] Furthermore, the carrier added to the extractant is mainly to extract the more polar components from the waste lithium battery electrolyte based on the principle of like dissolves like. These more polar components include carbonates such as propylene carbonate and ethylene carbonate.

[0035] In this embodiment of the invention, a first pressure sensor 91 and a first temperature sensor 92 are respectively installed on the outer wall of the extraction vessel 90. The first pressure sensor 91 is used to measure the extraction pressure inside the extraction vessel 90, and the first temperature sensor 92 is used to measure the extraction temperature inside the extraction vessel 90. By adjusting the extraction pressure and extraction temperature inside the extraction vessel 90, the CO2 inside the extraction vessel 90 can be made to be in a supercritical state. The supercritical CO2 can extract carbonate substances and lithium salt substances from the electrolyte of waste batteries.

[0036] Specifically, supercritical carbon dioxide has a density close to that of a liquid, but a viscosity similar to that of a gas. This unique combination of gas-liquid properties gives supercritical fluids an advantage. Due to the high compressibility of supercritical carbon dioxide, increasing its pressure can effectively increase its density and thus its solubility. However, as the pressure of supercritical carbon dioxide increases to a certain level, the viscosity of the fluid increases, which becomes unfavorable for extraction.

[0037] In this embodiment of the invention, the extraction pressure in the extraction vessel 90 ranges from 10 MPa to 50 MPa, the extraction temperature ranges from 30°C to 60°C, and the extraction time ranges from 30 min to 120 min.

[0038] In this embodiment of the invention, the extraction vessel 90 and the separation vessel 100 are connected by a fourth pipeline, on which a first valve V1, a second valve V2, and a third valve V3 are installed. The second valve V2 is connected in series with the first valve V1, and the third valve V3 is connected in parallel with the second valve V2. The extraction transmission system is connected to the separation vessel 100 by a fifth pipeline, on which a fourth valve V4, a fifth valve V5, and a sixth valve V6 are installed. The fifth valve V5 is connected in series with the fourth valve V4, and the sixth valve V6 is connected in parallel with the fifth valve V5. In this embodiment of the invention, a second pressure sensor 101 and a second temperature sensor 102 are respectively installed on the outer wall of the separation vessel 100. The second pressure sensor 101 is used to measure the extraction pressure inside the separation vessel 100, and the second temperature sensor 102 is used to measure the extraction temperature inside the separation vessel 100. By adjusting the separation pressure and separation temperature inside the extraction vessel 90, the CO2 inside the separation vessel 100 can be kept in a gaseous state, thereby separating the CO2 from the electrolyte extract in the extraction phase. The CO2 is then collected through a pipeline connected to a seventh valve V7 at the bottom of the separation vessel 100. The electrolyte extract includes a carrier, carbonate substances, and lithium salts.

[0039] Specifically, the pressure range inside the separation vessel 100 is 5MPa~7MPa, and the temperature range inside the separation vessel 100 is 30℃~60℃.

[0040] In this embodiment of the invention, both the extraction vessel 90 and the separation vessel 100 include a heating element 110, which is used to heat the extraction vessel 90 and the separation vessel 100.

[0041] In the extraction transmission system, an eighth valve V8 is installed on the pipeline between the CO2 storage tank and the purifier 20, and a ninth valve V9 is also installed on the pipeline between the second end of the mixer 70 and the extraction vessel 90. In this embodiment of the invention, a tenth valve V10 is also installed on the outer wall of the extraction vessel 90. The tenth valve V10 is used to vent CO2 from the extraction vessel 90.

[0042] Specifically, the first valve V1, the third valve V3, the fourth valve V4, the sixth valve V6, the seventh valve V7, the eighth valve V8, the ninth valve V9, and the tenth valve V10 are all conventional valves with conventional structures, while the second valve V2 and the fifth valve V5 are both fine-tuning valves. Among them, the fine-tuning valves can precisely control the flow rate of CO2 gas, thereby controlling the pressure of the extraction vessel 90 and the separation vessel 100 respectively.

[0043] To facilitate a better understanding of the embodiments of the present invention, the usage process of the embodiments of this application is described in detail below: First, before starting the recycling and processing device provided in this embodiment of the invention, ensure that all valves (first valve V1 to tenth valve V10) are in the closed state; then, put the discharged waste lithium battery into the crushing chamber of the crushing mechanism 80 through the crushing funnel; then turn on the first drive motor 81, drive the first connecting shaft 82 to start rotating, the first gear 84 to start rotating, and the second gear 85 meshing with it to rotate, thereby driving the second connecting shaft 838 to rotate, and the first crushing roller 86 and the second crushing roller 878-7 to start working to crush the waste lithium battery.

[0044] Secondly, after the waste lithium batteries are completely crushed, the first solenoid valve 891 or the second solenoid valve 892 is opened, causing the feed baffle 812 to move in a direction close to the first solenoid valve 891 or the second solenoid valve 892, thereby opening the feed inlet and allowing the crushed waste lithium batteries to directly enter the extraction vessel 90. Afterwards, the switch of the first drive motor 81 is turned off, stopping the first crushing roller 86 and the second crushing roller 87 from working. Simultaneously, the switch of the first solenoid valve 891 or the second solenoid valve 892 is closed, causing the feed baffle 812 to seal the feed inlet.

[0045] Next, turn on the heating switch of the extraction vessel 90 and the heating switch of the separation vessel 100 respectively, and set the extraction temperature and separation temperature to 40℃ respectively.

[0046] Then, turn on the refrigeration unit 30, and simultaneously open the eighth valve V8, the ninth valve V9, the fourth valve V4, the sixth valve V6, the third valve V3, and the first valve V1 to connect the pipelines between the extraction transmission system, the extraction vessel 90, and the separation vessel 100, while keeping them disconnected from the outside. When the gas pressure in the CO2 storage tank, the extraction pressure in the extraction vessel 90, and the cavity pressure in the separation vessel 100 are equal, close the third valve V3 and the sixth valve V6 respectively, and simultaneously open the second valve V2 and the fifth valve V5. Also, turn on the CO2 pump and the carrier pump 60 respectively. The extraction pressure in the extraction vessel 90 is finely adjusted to 25 MPa through the second valve V2, and the separation pressure in the separation vessel 100 is finely adjusted to 6 MPa through the fifth valve V5.

[0047] Subsequently, extraction is carried out in extraction vessel 90. The supercritical CO2 in extraction vessel 90 extracts the electrolyte from the crushed waste lithium battery to obtain the extract phase and the raffinate phase. The extract phase includes the carrier, supercritical CO2, and carbonate and lithium salt substances in the electrolyte. The raffinate phase consists of the solution components in the waste lithium battery electrolyte that are not extracted by the carrier and supercritical CO2, the crushed battery casing material, and the electrode sheet material. The extraction time is 1 hour.

[0048] Then, the extract phase is transferred to the separation vessel 100 via pipeline. The CO2 in the separation vessel 100 becomes gaseous, and the carbonates, carriers, and lithium salts in the extract phase are insoluble in the gaseous CO2. After extraction, the seventh valve V7 is opened, and the electrolyte extract in the extract phase is collected through the pipeline connected to the seventh valve V7 at the bottom of the separation vessel 100. The electrolyte extract includes carriers, carbonates, and lithium salts. The collected electrolyte extract is subjected to vacuum distillation to remove the carriers, yielding the carbonates and lithium salts to be recovered. Simultaneously, the gaseous CO2 in the separation vessel 100 continues to flow back to the purifier 20 via pipeline.

[0049] Next, shut down the CO2 pump and carrier pump 60, then close the ninth valve V9 and the first valve V1, while opening the tenth valve V10 to vent the CO2 from the extraction vessel 90.

[0050] Finally, the second drive motor 94 is turned on, which drives the third connecting shaft 95 to rotate. The third connecting shaft 95 drives the feed plug 96 to rotate upward to loosen it, so as to discharge the residual phase.

[0051] The supercritical CO2 extraction method used in this invention has a series of advantages, such as high efficiency, no secondary pollution to the environment, no solvent residue, and good product reduction. It can overcome the disadvantages of high-temperature incineration and chemical methods. In addition, CO2 is inexpensive, readily available, stable, non-toxic, non-flammable, and has high safety performance.

[0052] Compared with the prior art, the embodiments of the present invention have at least the following effects: First, the embodiments of the present invention utilize supercritical CO2 to recover electrolyte from waste lithium batteries, which is highly efficient, causes no secondary pollution to the environment, leaves no solvent residue, and has good product reduction. Second, the embodiment of the present invention is provided with a carrier storage tank 50, which can be used to extract highly polar components in waste lithium battery electrolyte; Third, the CO2 provided in this embodiment of the invention is non-toxic, odorless, non-flammable, inexpensive, readily available, and recyclable; Fourth, in this embodiment of the invention, a crushing mechanism 80 is separately provided on the extraction vessel 90, so that the waste lithium battery can be directly put into the extraction vessel 90 after being crushed, without having to go through a complicated transfer path. Fifth, in this embodiment of the invention, an automatic discharge mechanism is separately provided at the bottom of the extraction vessel 90, so that the extraction vessel 90 does not need to be opened for unloading after each extraction, which is convenient and saves time.

[0053] In summary, unlike existing technologies, this invention provides a recycling and processing device for waste lithium battery electrolyte, including an extraction and transmission system, an extraction vessel 90, and a separation vessel 100. The extraction and transmission system, the extraction vessel 90, and the separation vessel 100 are connected to form a closed loop via pipelines. A crushing mechanism 80 with a crushing chamber is installed on the top of the extraction vessel 90, and the cavity inside the extraction vessel 90 can be closedly connected to the crushing chamber. The extraction and transmission system is used to simultaneously deliver CO2 and a carrier to the extraction vessel 90; the crushing mechanism 80 is used to crush the waste lithium batteries; and the extraction vessel 90 is used to bring the CO2 to a supercritical state and to process the electrolyte. The electrolyte in the waste lithium battery after crushing is extracted to obtain an extract phase and a raffinate phase; the separation vessel 100 is used to separate the electrolyte extract from the extract phase; the waste lithium battery electrolyte recycling device provided by the present invention uses supercritical CO2 in the extraction vessel 90 to extract the crushed waste lithium battery to obtain an extract phase, and collects the electrolyte extract from the extract phase in the separation vessel 100. This recycling device can automatically recycle the electrolyte in waste lithium batteries, with no secondary pollution to the environment, no solvent residue, good product reduction degree, and effectively improves recycling efficiency.

[0054] It should be noted that all the above embodiments belong to the same inventive concept, and the descriptions of each embodiment have different focuses. Where the description in a particular embodiment is not exhaustive, please refer to the descriptions in other embodiments. The above embodiments only illustrate the implementation of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the invention patent. It should be pointed out that for those skilled in the art, several modifications and improvements can be made without departing from the inventive concept, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A device for recycling and processing waste lithium battery electrolyte, characterized in that, It includes an extraction and transport system, an extraction vessel, and a separation vessel. The extraction and transport system, the extraction vessel, and the separation vessel are connected to form a closed loop through pipelines. A crushing mechanism with a crushing chamber is installed on the top of the extraction vessel, and the cavity inside the extraction vessel is in closed communication with the crushing chamber. The extraction and transport system is used to simultaneously deliver CO2 and a carrier into the extraction vessel; the crushing mechanism is used to crush the waste lithium batteries; the extraction vessel is used to bring CO2 to a supercritical state and extract the electrolyte in the crushed waste lithium batteries to obtain an extract phase and a raffinate phase; the separation vessel is used to separate the electrolyte extract from the extract phase. The bottom plate of the crushing mechanism near the extraction vessel has a feed inlet. A first solenoid valve and a second solenoid valve are fixedly installed at the two ends of the bottom plate near the feed inlet, respectively. A first telescopic spring is fixedly installed on the side of the first solenoid valve away from the bottom plate, and a second telescopic spring is fixedly installed on the side of the second solenoid valve away from the bottom plate. The crushing mechanism also includes a feeding baffle, and a first iron block and a second iron block are fixedly installed at both ends of the feeding baffle, respectively; the first iron block is fixedly connected to the first telescopic spring, and the second iron block is fixedly connected to the second telescopic spring.

2. The waste lithium battery electrolyte recycling and processing device according to claim 1, characterized in that, A first connecting shaft is provided inside the crushing chamber. One end of the first connecting shaft passes through the crushing chamber and is fixedly connected to the first drive motor. A first gear and a first crushing roller spaced apart from the first gear are also fixedly sleeved on the first connecting shaft. The crushing chamber is further provided with a second connecting shaft, on which a second gear and a second crushing roller spaced apart are fixedly sleeved. The second gear meshes with the first gear.

3. The waste lithium battery electrolyte recycling and processing device according to claim 2, characterized in that, Multiple crushing teeth are fixed on the outer walls of both the first and second crushing rollers.

4. The waste lithium battery electrolyte recycling and processing device according to claim 2, characterized in that, The crushing mechanism is also provided with a first baffle and a second baffle that are spaced apart on the side near the extraction vessel. One end of the first baffle is fixedly connected to the inner wall of one side of the crushing mechanism, and the other end of the first baffle passes through the feed inlet and is integrally formed with the shell of the extraction vessel. One end of the second baffle is fixedly connected to the inner wall of the other side of the crushing mechanism, and the other end of the second baffle passes through the feed inlet and is integrally formed with the shell of the extraction vessel. The first baffle has a first through hole, the second baffle has a second through hole, and the feed partition passes through the first through hole and the second through hole respectively; the length of the feed partition is greater than the minimum distance between the first baffle and the second baffle.

5. The waste lithium battery electrolyte recycling and processing device according to claim 1, characterized in that, An automatic discharge mechanism is fixedly installed on the side of the extraction vessel away from the crushing mechanism. The discharge chamber of the automatic discharge mechanism can be closed and communicated with the chamber inside the extraction vessel. The automatic discharge mechanism includes a discharge plug, a third connecting shaft, a fixing block, and a second drive motor. The feed plug is threaded to the inner wall of the discharge cavity, and the fixing block is fixedly connected to the bottom of the discharge cavity; one end of the third connecting shaft passes through the feed plug and extends into the cavity of the extraction vessel, and the other end of the third connecting shaft passes through the fixing block and is fixedly connected to the second drive motor on the outside of the discharge cavity.

6. The waste lithium battery electrolyte recycling and processing device according to claim 5, characterized in that, The side wall of the discharge cavity is provided with a discharge groove, and multiple levers are fixedly installed on the outer side wall of the third connecting shaft.

7. The waste lithium battery electrolyte recycling and processing device according to claim 1, characterized in that, The extraction and transmission system includes a CO2 transmission pipeline and a carrier transmission pipeline. The CO2 transmission pipeline includes a CO2 storage tank, a purifier, a refrigerator, and a CO2 pump connected in sequence through the pipeline. The carrier transmission pipeline includes a carrier storage tank and a carrier pump connected in sequence through the pipeline. The extraction transfer system further includes a mixer, the first end of which is connected to the CO2 pump via a first pipeline, and the first end of which is also connected to the carrier pump via a second pipeline; the second end of which is connected to the extraction vessel via a third pipeline.

8. The waste lithium battery electrolyte recycling and processing device according to claim 1, characterized in that, The extraction vessel and the separation vessel are connected via a fourth pipeline, on which a first valve, a second valve, and a third valve are installed. The second valve is connected in series with the first valve, and the third valve is connected in parallel with the second valve. The extraction transmission system is connected to the separation vessel via a fifth pipeline, on which a fourth valve, a fifth valve, and a sixth valve are installed. The fifth valve is connected in series with the fourth valve, and the sixth valve is connected in parallel with the fifth valve. Both the second valve and the fifth valve are fine-tuning valves.

9. The waste lithium battery electrolyte recycling and processing device according to claim 1, characterized in that, The extraction vessel is equipped with a first pressure sensor and a first temperature sensor on its outer wall, and the separation vessel is equipped with a second pressure sensor and a second temperature sensor on its outer wall.

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