A device for recycling waste lithium battery materials by using supercritical water oxidation technology

Abstract

This invention discloses a device for recycling waste lithium battery materials using supercritical water oxidation technology. The device comprises a supercritical water generator, a supercritical water oxidation reactor, a supercritical water reduction reactor, a pulsed resonance extraction reactor, and a central controller connected in series via pipelines. It is equipped with temperature and pressure control equipment and electric valves to achieve fully automated control of the entire process. The supercritical water generator prepares supercritical water at 374℃ and 22.1MPa. The oxidation reactor degrades the organic components of the crushed waste lithium battery material. The reduction reactor purifies the metal components through temperature and pressure regulation. The extraction reactor uses electronic pulses and water oscillation to achieve fractional separation of valuable metals from purified water. This device achieves integrated continuous processing of "oxidation-reduction-extraction," solving the problems of high energy consumption, high pollution, and cumbersome processes associated with traditional methods. It has advantages such as high metal recovery rate, no secondary pollution, and high degree of automation, making it suitable for large-scale resource recycling.

Description

Technical Field

[0001] This invention relates to the field of waste lithium battery resource recycling equipment technology, specifically to a device for recycling waste lithium battery materials using supercritical water oxidation technology. Background Technology

[0002] With the rapid development of the new energy industry, the application scope of lithium batteries is constantly expanding, and the amount of waste lithium batteries generated is also increasing year by year. Waste lithium batteries contain a variety of precious metals such as lithium, cobalt, and nickel, and have extremely high recycling value; however, they also contain harmful substances such as organic electrolytes and plastic separators. If not handled properly, they can cause serious environmental pollution. Therefore, the efficient and environmentally friendly recycling of waste lithium batteries has become a key issue that the industry urgently needs to address. Currently, the mainstream technology for recycling waste lithium batteries is acid-base leaching. This technology requires multiple processes such as crushing, roasting, acid leaching, extraction, and precipitation, resulting in significant problems such as cumbersome processes, long recycling cycles, and severe secondary pollution. For example, Chinese patent CN108731725A discloses a method for recycling positive electrode materials from waste lithium batteries, using a sulfuric acid + hydrogen peroxide system for leaching. While this method can recover some metals, it consumes large amounts of acid and alkali reagents, generates waste liquid that is difficult to treat, and achieves a metal recovery rate of only 85%-90%, resulting in limited resource utilization. Chinese patent CN110223156A discloses a pyrometallurgical recycling process for waste lithium batteries, which decomposes organic matter through high-temperature roasting followed by acid leaching to recover metals. This process suffers from high energy consumption (roasting temperature needs to reach 800-1000℃), the generation of toxic gases during roasting, and severe equipment corrosion, which does not align with the trend of green and low-carbon development.

[0003] In summary, existing waste lithium battery recycling technologies either rely on chemical reagents, leading to secondary pollution, or suffer from high energy consumption and low recycling efficiency. Therefore, developing a waste lithium battery recycling device with a reasonable structure, stable operation, and high recycling efficiency has significant practical significance and application value. Summary of the Invention

[0004] The purpose of this invention is to provide a device for recycling waste lithium battery materials using supercritical water oxidation technology, thereby solving the problems mentioned in the background section. To achieve the above objective, this invention provides the following technical solution: A device for recycling waste lithium battery materials using supercritical water oxidation technology includes a supercritical water generator (1), a supercritical water oxidation reactor (2), a supercritical water reduction reactor (3), a pulse resonance extraction reactor (4), and a central controller, which are connected in sequence by pipelines. A supercritical water delivery pipe (C1) is provided between the supercritical water generator (1) and the supercritical water oxidation reactor (2). A supercritical water oxide delivery pipe (C2) is provided between the supercritical water oxidation reactor (2) and the supercritical water reduction reactor (3). A supercritical water reduction substance delivery pipe (C3) is provided between the supercritical water reduction reactor (3) and the pulse resonance extraction reactor (4). A first control valve (F1) is installed on the supercritical water delivery pipe (C1), a second control valve (F2) is installed on the supercritical water oxide delivery pipe (C2), and a third control valve (F3) is installed on the supercritical water reduction substance delivery pipe (C3). The supercritical water generator (1) is equipped with a first temperature and pressure control device (101) fixedly installed on its outside. The supercritical water oxidation vessel (2) is equipped with a second temperature and pressure control device (201) fixedly installed on its outside. The supercritical water reduction vessel (3) is equipped with a third temperature and pressure control device (301) fixedly installed on its outside. The central controller is electrically connected to the supercritical water generator (1), the supercritical water oxidation vessel (2), the supercritical water reduction vessel (3), the pulse resonance extraction vessel (4), the first temperature and pressure control device (101), the second temperature and pressure control device (201), the third temperature and pressure control device (301), the first control valve (F1), the second control valve (F2), and the third control valve (F3), respectively. The controller can uniformly regulate the start and stop, operating parameters, and material conveying of each device through a preset program, thereby achieving full-process automated and precise control.

[0005] Furthermore, the first temperature and pressure control device (101) is an electric temperature and pressure integrated device, which is connected to the gas path of the sealed tank of the supercritical water generator (1). It can deliver 374°C high temperature and 24MPa high pressure gas into the sealed tank, causing the ordinary water in the tank to be quickly converted into supercritical water at 374°C and 22.1MPa. After the supercritical water is output, the first temperature and pressure control device (101) can reduce the pressure of the sealed tank to normal pressure, so as to facilitate the refilling of ordinary water and realize the continuous generation of supercritical water.

[0006] Furthermore, a storage jar device (202) is fixedly installed on the top of the supercritical water oxidation reactor (2). The storage jar device (202) is used to store waste lithium battery particles after crushing and screening pretreatment. An electric control door is provided on the side facing the inside of the reactor. The electric control door is electrically connected to the central controller and can realize precise feeding in a timed and quantitative manner according to a preset program. The second temperature and pressure control device (201) is connected to the gas path of the supercritical water oxidation reactor (2) and can continuously deliver constant temperature and pressure gas into the reactor to maintain a stable supercritical oxidation reaction environment of 374℃ and 22.1MPa inside the reactor.

[0007] Furthermore, an electrically regulated exhaust vent pipe (302) is installed on the top of the supercritical water reduction reactor (3). One end of the electrically regulated exhaust vent pipe (302) extends into the upper space inside the reactor, and the other end is connected to the tail gas treatment device. An electric control valve is installed on the pipeline. The electric control valve is electrically connected to the central controller and can automatically discharge the inorganic combustion gas and excess heat generated in the reactor reaction. The third temperature and pressure control device (301) is connected to the gas path of the supercritical water reduction reactor (3) and can deliver inert gas below 374℃ and 22.1MPa into the reactor or discharge gas outside the reactor, flexibly adjusting the temperature and pressure inside the reactor to 180-350℃ and 5-20MPa to achieve the reduction and conditioning treatment of materials.

[0008] Furthermore, the pulse resonance extraction vessel (4) has a vertical vessel structure with an open air vent (403) at the top. A pure water filter membrane (401) (tilt angle 45-60°, filter membrane pore size 0.1-1μm) is installed inside at an angle. At least four electronic pulse generators (406) are evenly distributed on the inner side wall of the vessel, and a water shaker (402) is fixedly installed at the center of the bottom of the vessel. The bottom of the vessel has independent pure water outlets (404) and metal material outlets (405), and each outlet is equipped with a control valve. The electronic pulse generator (406) outputs a pulse frequency of 10-50kHz, and the water shaker (402) outputs an oscillation frequency of 50-200Hz. Both are electrically connected to the central controller, and the solid-liquid separation effect can be enhanced by adjusting the pulse intensity and oscillation frequency. The beneficial effects of this invention are as follows: High degree of integration: This invention integrates four functional units—supercritical water preparation, oxidative degradation, reduction conditioning, and pulse extraction—into a continuous integrated processing flow with smooth process connections, significantly improving the automation level and operational efficiency of waste lithium battery recycling, and enabling large-scale production.

[0009] Precise temperature and pressure control: Three sets of independent temperature and pressure control devices are set up to individually control the supercritical water generator, the supercritical water oxidation reactor, and the supercritical water reduction reactor. The operating conditions of each unit do not interfere with each other, ensuring stable supercritical water preparation, sufficient oxidation reaction, and precise reduction conditioning, effectively improving the degradation rate of organic impurities and the dissociation effect of metals.

[0010] High level of automation: All equipment is controlled by a central controller, realizing the fully automated operation of supercritical water preparation, feeding, reaction, conveying, extraction and separation. No continuous manual supervision is required, reducing human operation errors and labor intensity. At the same time, the timing and amount of material conveying are precisely controlled, improving material utilization.

[0011] Green and environmentally friendly: Supercritical water oxidation technology is used to degrade organic impurities without the need to add strong acid or alkali agents, thus avoiding the generation of highly polluting wastewater and waste residue. The small amount of waste gas generated during the reaction is treated by the tail gas treatment device before being discharged, which is environmentally friendly and in line with the development trend of green recycling of solid waste resources.

[0012] Excellent recycling effect: The back end adopts an extraction and separation method that combines electronic pulse resonance and mechanical oscillation, coupled with an inclined high-precision filter membrane, to achieve efficient stratified separation of valuable metal particles and water. The metal recovery purity is high (up to 95% or more), the resource recovery rate is high, and the economic benefits of recycling operations are significantly improved. Attached Figure Description

[0013] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0014] Figure 1 This is a schematic diagram of the device for recycling waste lithium battery materials according to the present invention.

[0015] Figure 2 This is a schematic diagram of the pulse resonance extraction vessel of the present invention.

[0016] It should be noted that the accompanying drawings are not necessarily drawn to scale, but are shown only in a schematic manner without affecting the reader's understanding. Detailed Implementation

[0017] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. 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 skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] In this invention, the terms "upper," "lower," "left," "right," "front," "rear," "top," "bottom," "inner," "outer," "middle," "vertical," "horizontal," "lateral," and "longitudinal" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are primarily for the purpose of better describing the invention and its embodiments, and are not intended to limit the indicated devices, elements, or components to having a specific orientation, or to be constructed and operated in a specific orientation.

[0019] Furthermore, in addition to indicating direction or positional relationship, some of the aforementioned terms may also have other meanings. For example, the term "above" may also be used in certain situations to indicate a dependency or connection. Those skilled in the art can understand the specific meaning of these terms in this invention based on the specific circumstances.

[0020] Furthermore, the terms "installation," "setup," "equipped with," "connection," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral structure; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium, or an internal connection between two devices, components, or parts. Those skilled in the art can understand the specific meaning of these terms in this invention based on the specific circumstances.

[0021] Furthermore, the terms "first," "second," etc., are primarily used to distinguish different devices, components, or parts (which may be the same or different in specific type and construction), and are not intended to indicate or imply the relative importance or quantity of the indicated devices, components, or parts. Unless otherwise stated, "a plurality of" means two or more.

[0022] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0023] It should also be further understood that the term "and / or" as used in this specification and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0024] See Figures 1 to 2 The supercritical water oxidation technology in this embodiment is used for the recycling of waste lithium battery materials. The core components include: a supercritical water generator 1, a first temperature and pressure control device 101, a supercritical water oxidation reactor 2, a second temperature and pressure control device 201, a storage tank device 202, a supercritical water reduction reactor 3, a third temperature and pressure control device 301, an electrically regulated exhaust and ventilation pipe 302, a pulse resonance extraction reactor 4, an electronic pulse generator 406, a water oscillator 402, a pure water filter membrane 401, a supercritical water delivery pipe C1, a supercritical water oxide delivery pipe C2, a supercritical water reduction substance delivery pipe C3, a first control valve F1, a second control valve F2, a third control valve F3, and a central controller.

[0025] The discharge end of the supercritical water generator 1 is connected to the inlet end of the supercritical water oxidation vessel 2 through the supercritical water conveying pipe C1. The discharge end of the supercritical water oxidation vessel 2 is connected to the inlet end of the supercritical water reduction vessel 3 through the supercritical water oxide conveying pipe C2. The discharge end of the supercritical water reduction vessel 3 is connected to the inlet end of the pulse resonance extraction vessel 4 through the supercritical water reduction substance conveying pipe C3, forming a closed material conveying path.

[0026] The first control valve F1 is installed in series in the middle of the supercritical water conveying pipe C1, the second control valve F2 is installed in series in the middle of the supercritical water oxide conveying pipe C2, and the third control valve F3 is installed in series in the middle of the supercritical water reducing substance conveying pipe C3, to control the material flow and flow rate of each pipe.

[0027] The first temperature and pressure control device 101 is fixed to the outer wall of the supercritical water generator 1 by a bracket, and its gas interface is connected to the inside of the sealed tank of the supercritical water generator 1; the second temperature and pressure control device 201 is fixed to the outer wall of the supercritical water oxidation reactor 2, and its gas interface is connected to the inside of the reactor body; the third temperature and pressure control device 301 is fixed to the outer wall of the supercritical water reduction reactor 3, and its gas interface is connected to the inside of the reactor body, so as to realize independent temperature and pressure control of each unit.

[0028] The storage tank 202 is fixed to the feed inlet at the top of the supercritical water oxidation reactor 2 via a flange, and its electric control door extends into the reactor body; the electrically regulated exhaust vent pipe 302 vertically penetrates the top wall of the supercritical water reduction reactor 3, with its lower end located in the upper space inside the reactor and its upper end connected to an external exhaust gas treatment device; the pure water filter membrane 401 is obliquely fixed to the middle of the pulse resonance extraction reactor 4 via a slot, and the electronic pulse generator 406 is evenly fixed to the inner side wall of the reactor below the pure water filter membrane 401 by bolts; the water shaker 402 is fixed to the center of the bottom of the reactor via a bracket; the pure water outlet 404 and the metal material outlet 405 are respectively opened on both sides of the bottom of the pulse resonance extraction reactor 4, and each outlet is equipped with a manual control valve.

[0029] The first temperature and pressure control device 101, the second temperature and pressure control device 201, the third temperature and pressure control device 301, the first control valve F1, the second control valve F2, the third control valve F3, the electric control door of the storage tank device 202, the electric control valve of the electric regulating exhaust vent pipe 302, the electronic pulse generator 406, and the water oscillator 402 are all connected to the signal output and signal input terminals of the central controller through wires, forming a complete electronic control linkage system.

[0030] The working principle of this device is based on the strong oxidizing properties of supercritical water, the component optimization effect of reduction conditioning, and the enhanced separation effect of pulse resonance. A central controller coordinates the operation of each unit to achieve efficient recycling of waste lithium batteries. The specific operating procedure is as follows: Pre-treatment stage: The waste lithium batteries are discharged, disassembled, crushed and screened to obtain lithium battery granules with a particle size of 0.5-5mm, which are then put into the storage tank 202 for later use; sufficient ordinary clean water is added to the sealed tank of the supercritical water generator 1, and the sealing of each pipeline connection, the initial state of the valves and the wiring of the electrical equipment are checked.

[0031] Supercritical water preparation stage: The central controller is started, and the operating parameters of each unit are set as follows: target temperature and pressure of 374℃ and 22.1MPa for the supercritical water generator; target temperature and pressure of 374℃ and 22.1MPa for the supercritical water oxidation reactor; target temperature and pressure of 250℃ and 10MPa for the supercritical water reduction reactor; electronic pulse frequency of 30kHz; and water oscillation frequency of 100Hz. The central controller starts the first temperature and pressure control device 101, whose gas heating module heats the gas to 374℃. The high-pressure gas delivery pump pressurizes the gas to 24MPa and introduces it into the sealed tank of the supercritical water generator 1. Under the action of high temperature and high pressure, ordinary water in the tank is rapidly converted into supercritical water at 374℃ and 22.1MPa, completing the preparation of supercritical water.

[0032] Supercritical water oxidation reaction stage: The central controller opens the first control valve F1, and supercritical water is uniformly fed into the supercritical water oxidation reactor 2 through the supercritical water delivery pipe C1; simultaneously, the second temperature and pressure control device 201 is activated to continuously supply constant temperature and pressure gas into the reactor to maintain the supercritical reaction environment. After the supercritical water level in the reactor reaches the preset value, the central controller controls the electric control door of the storage tank device 202 to open, and lithium battery particles are added into the reactor at a preset feeding rate of 5 kg / batch. After feeding is completed, the electric control door is closed. The strong oxidizing properties of supercritical water rapidly decompose organic impurities such as electrolyte, binder, and separator in the lithium battery particles, degrading them into harmless substances such as carbon dioxide and water. At the same time, the electrode active material and current collector are completely dissociated, forming a mixture containing metal oxides and elemental metals. The oxidation reaction lasts for 60 minutes.

[0033] Reduction and Conditioning Stage and Exhaust Gas Emission: After the oxidation reaction is completed, the central controller closes the first control valve F1 and opens the second control valve F2. The oxidized mixture flows into the supercritical water reduction reactor 3 through the supercritical water oxide conveying pipe C2. The central controller activates the third temperature and pressure control device 301 to introduce nitrogen inert gas into the reactor, adjusting the temperature and pressure inside the reactor to 250℃ and 10MPa. Under these conditions, the mixture undergoes reduction and conditioning treatment, and the metal oxides are reduced to high-purity metal elements, optimizing the composition of the material. The small amount of inorganic combustion gas and excess heat generated during the reaction are automatically discharged by the central controller through the electrically controlled valve of the electrically regulated exhaust vent pipe 302 based on the pressure data inside the reactor. After treatment by the tail gas treatment device, the gas meets emission standards. The reduction and conditioning reaction lasts for 40 minutes.

[0034] Pulse Resonance Extraction and Separation Stage: After reduction and conditioning, the central controller closes the second control valve F2 and opens the third control valve F3. The conditioned mixture containing metal particles and water is sent into the pulse resonance extraction vessel 4 through the supercritical water reducing agent delivery pipe C3. The central controller starts the electronic pulse generator 406 and the water shaker 402. The high-frequency vibration generated by the electronic pulse and the mechanical vibration generated by the water shaker 402 work together to accelerate the stratification and separation of metal particles and water. The inclined pure water filter membrane 401 filters the water to remove fine impurities. The purified water is discharged from the pure water outlet 404 for recycling. The metal particles settle to the bottom of the vessel under gravity. After extraction and separation for 30 minutes, the electronic pulse generator 406 and the water shaker 402 are closed, and the control valve of the metal material outlet 405 is opened to collect high-purity lithium, cobalt, nickel, manganese and other metal materials, completing the single-batch recovery operation.

[0035] Cyclic Operation Phase: After a single batch of operations is completed, the central controller controls each device to reset and close the second control valve F2 and the third control valve F3. The first temperature and pressure control device 101 starts the pressure reducing valve to reduce the pressure of the supercritical water generator 1 sealed tank to atmospheric pressure. After the staff replenishes clean water and lithium battery granules, the next batch of operations can be started to achieve continuous recycling.

[0036] Regarding the embodiments of the present invention, it should also be noted that, without conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other to obtain new embodiments.

[0037] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. The scope of protection of the present invention should be determined by the scope of the claims. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A device for recycling waste lithium battery materials using supercritical water oxidation technology, characterized in that: The system includes a supercritical water generator (1), a supercritical water oxidation reactor (2), a supercritical water reduction reactor (3), a pulse resonance extraction reactor (4), and a central controller, all connected sequentially by pipes. The supercritical water generator (1) and the supercritical water oxidation reactor (2) are connected by a supercritical water delivery pipe (C1), the supercritical water oxidation reactor (2) and the supercritical water reduction reactor (3) are connected by a supercritical water oxide delivery pipe (C2), and the supercritical water reduction reactor (3) and the pulse resonance extraction reactor (4) are connected by a supercritical water reducing substance delivery pipe (C3). The supercritical water delivery pipe (C1) is equipped with a first valve (F1), the supercritical water oxide delivery pipe (C2) is connected to a second valve (F2), and the supercritical water reducing substance delivery pipe (C3) is connected to a third valve (F3). The supercritical water generator (1) is equipped with a first temperature and pressure control device (101), the supercritical water oxidation reactor (2) is equipped with a second temperature and pressure control device (201), and the supercritical water reduction reactor (3) is equipped with a third temperature and pressure control device (301). The central controller is electrically connected to the supercritical water generator (1), the supercritical water oxidation reactor (2), the supercritical water reduction reactor (3), the pulse resonance extraction reactor (4), the first temperature and pressure control device (101), the second temperature and pressure control device (201), the third temperature and pressure control device (301), the first valve (F1), the second valve (F2), and the third valve (F3).

2. The apparatus for recycling waste lithium battery materials using supercritical water oxidation technology according to claim 1, characterized in that: The first temperature and pressure control device (101) is an electric temperature and pressure control device. The first temperature and pressure control device (101) can deliver 374°C high temperature and 24MPa high pressure gas into the sealed tank of the supercritical water generator (1), so that the ordinary water in the tank is converted into supercritical water at 374°C and 22.1MPa. After the delivery is completed, the first temperature and pressure control device (101) can depressurize the sealed tank so that new water can be injected to circulate and generate supercritical water.

3. The apparatus for recycling waste lithium battery materials using supercritical water oxidation technology according to claim 1, characterized in that: The supporting equipment of the supercritical water oxidation reactor (2) includes a second temperature and pressure control device (201) and a storage tank device (202); the second temperature and pressure control device (201) can continuously supply gas into the supercritical water oxidation reactor (2) to maintain the supercritical conditions of 374℃ and 22.1MPa inside the reactor; the storage tank device (202) is set on the top of the supercritical water oxidation reactor (2) and is used to store waste lithium battery crushed material. The storage tank device (202) has a control door on the side facing the inside of the reactor. The control door is electrically connected to the central controller to realize precise feeding.

4. The apparatus for recycling waste lithium battery materials using supercritical water oxidation technology according to claim 1, characterized in that: The supporting equipment of the supercritical water reduction reactor (3) includes a third temperature and pressure control device (301) and an electrically regulated exhaust vent pipe (302); the third temperature and pressure control device (301) can deliver gas below 374°C and 22.1 MPa into the supercritical water reduction reactor (3), or discharge gas to the outside of the reactor to regulate the internal temperature and pressure; the electrically regulated exhaust vent pipe (302) is located at the top of the supercritical water reduction reactor (3) and is electrically connected to the central controller, and is used to discharge inorganic combustion gases and hot gases inside the reactor.

5. The apparatus for recycling waste lithium battery materials using supercritical water oxidation technology according to claim 1, characterized in that: The pulse resonance extraction vessel (4) is provided with an open air vent (403) at the top, and is provided with an electronic pulse generator (406), a water shaker (402) and a pure water filter membrane (401) inside. It is provided with a pure water outlet (404) and a metal material outlet (405) at the bottom. The electronic pulse generator (406) is evenly distributed on the inner side wall of the vessel, the water shaker (402) is installed at the center of the bottom of the vessel, and the pure water filter membrane (401) is inclinedly arranged in the middle of the vessel. The central controller is electrically connected to the electronic pulse generator (406) and the water shaker (402).

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