Electrolytic furnace for thermal decomposition of ternary acid leachate

Abstract

The utility model discloses an electrolytic furnace for thermal decomposition of a ternary acid leaching solution, and relates to the technical field of lithium ion battery recovery. The electrolytic furnace for thermal decomposition of the ternary acid leachate comprises a furnace body, a nozzle and a plurality of electric heating pipes, and a discharge port is formed in the side wall of the furnace body; the nozzle is arranged at the bottom of the furnace body, the plurality of electric heating pipes are arranged in the furnace body above the nozzle, the plurality of electric heating pipes are arranged close to the inner wall of the furnace body, the plurality of electric heating pipes are annularly distributed, an inner surrounding area is defined by the plurality of electric heating pipes, and the inner surrounding area is arranged corresponding to the spray holes. According to the technical scheme, the electric heating pipe is adopted to generate heat, compared with the existing mode that natural gas serves as fuel to be incinerated to generate heat, the generation amount of pollutants can be effectively reduced, the device is more environment-friendly, the thermal decomposition effect on the ternary acid leaching liquid is better, the decomposition efficiency is high, and the product yield is effectively improved.

Description

Technical Field

[0001] This utility model relates to the field of lithium-ion battery recycling technology, and in particular to an electrolytic furnace for thermally decomposing tribasic acid leachate. Background Technology

[0002] Currently, the main method used to recover nickel, cobalt, and manganese from the cathode materials of ternary lithium-ion batteries is wet recycling. The wet recycling process includes: dismantling and pre-treating waste ternary lithium-ion batteries to obtain cathode material powder; using sulfuric acid, hydrochloric acid, or nitric acid as leaching agents to immerse the cathode material powder in the leaching agent to obtain a ternary acid leachate containing nickel, cobalt, and manganese; adding a precipitant and adjusting the pH to precipitate the nickel, cobalt, and manganese from the ternary acid leachate, thereby achieving the recovery of nickel, cobalt, and manganese.

[0003] Separating nickel, cobalt, and manganese from ternary acid leaching solutions by precipitation can easily lead to uncontrollable particle size of the precipitated particles, affecting the performance of the recovered nickel, cobalt, and manganese materials. Furthermore, due to solubility product limitations, incomplete precipitation reactions are prone to occur, with some metals potentially existing in colloidal or complex forms, making complete precipitation difficult and reducing product recovery rates.

[0004] The hot air generated by the incinerator is used to thermally decompose the ternary acid leachate to produce oxide powder products, including nickel oxide, cobalt oxide, and manganese oxide. Although thermal decomposition can improve the product recovery rate and control the particle size of the product, the heat generated by the incinerator comes from the combustion of natural gas. During combustion, too much air needs to be input, which leads to an excessively high nitrogen content. During combustion, nitrogen easily combines with oxygen to form excessive nitrogen oxides. In addition, natural gas contains impurities such as sulfur, so its combustion products contain more pollutants, increasing the burden on subsequent exhaust gas treatment. Utility Model Content

[0005] The main purpose of this invention is to propose an electrolytic furnace for the thermal decomposition of tribasic acid leachate, which aims to solve the problem that existing incinerators easily generate too many pollutants when thermally decomposing tribasic acid leachate.

[0006] To achieve the above objectives, this utility model proposes an electrolytic furnace for the thermal decomposition of tribasic acid leachate, comprising:

[0007] The furnace body has a discharge port on its side wall;

[0008] A nozzle, disposed at the bottom of the furnace body, has a feed end and a spray hole disposed opposite each other. The feed end is provided with an ejector gas inlet and a raw material solution inlet, and the spray hole is located inside the furnace body; and...

[0009] At least one electric heating tube is disposed in the furnace body above the spray hole, and multiple electric heating tubes are disposed close to the inner wall of the furnace body and are arranged in a ring. The multiple electric heating tubes define an inner perimeter area, which is disposed corresponding to the spray hole.

[0010] In one embodiment, the electrolytic furnace further includes a baffle plate disposed in the lower part of the furnace body, and the nozzle penetrates the baffle plate, with the nozzle located above the baffle plate.

[0011] In one embodiment, a hand hole is provided on the side wall of the furnace body between the baffle plate and the electric heating tube.

[0012] In one embodiment, the electrolytic furnace further includes a gas distribution device, which includes a gas distribution plate and a first purging gas pipe. The gas distribution plate is disposed in the furnace body below the baffle plate, and the first purging gas pipe is disposed at the bottom of the furnace body, with the outlet end of the first purging gas pipe connected to the bottom of the furnace body. The baffle plate is provided with a porous structure.

[0013] In one embodiment, the gas distribution device further includes a cylinder and a second purge gas pipe. The cylinder is disposed between the gas distribution plate and the bottom end of the furnace body, and the nozzle passes through the cylinder, the gas distribution plate and the baffle plate in sequence. The second purge gas pipe is disposed on the side wall of the furnace body below the gas distribution plate, and the outlet end of the second purge gas pipe extends into the cylinder.

[0014] In one embodiment, the outlet end of the second purge air pipe is positioned upwards.

[0015] In one embodiment, the electrolytic furnace further includes a hammer, which is disposed on the outer wall of the furnace body.

[0016] In one embodiment, the tapper is at least one set, and multiple sets of the tapper are arranged along the axial direction of the furnace body, with each set of the tapper distributed in a ring on the outer wall of the furnace body.

[0017] In one embodiment, each of the electric heating tubes is a U-shaped electric heating tube, and each of the U-shaped electric heating tubes is arranged along the axial direction of the furnace body; and / or,

[0018] There are multiple discharge ports, which are distributed along the axial direction of the furnace body.

[0019] In one embodiment, the electrolytic furnace further includes a tube sheet disposed in the upper part of the furnace body, and each of the electric heating tubes is mounted on the tube sheet; and / or,

[0020] A sight glass is installed on the side wall of the furnace body.

[0021] In this invention, the ternary acid leaching solution is ejected from the nozzle orifice under the action of an induction gas flow, forming a mist. The misty raw material enters the inner area enclosed by an electric heating tube, which heats the raw material through thermal radiation. The water in the misty raw material solution evaporates rapidly, and the raw material undergoes thorough thermal decomposition to form oxide powder, including nickel oxide, manganese oxide, and cobalt oxide. The water vapor formed after heating, as well as the oxide powder formed by thermal decomposition, are discharged from the outlet in the form of a gas flow.

[0022] The technical solution of this utility model uses an electric heating tube to generate heat in the form of outward radiation, and uses a low gas-liquid ratio to achieve atomized feeding of the tribasic acid leachate. Compared with the existing method of using natural gas as fuel to generate hot air for pyrolysis of the tribasic acid leachate, it greatly reduces the amount of air used, effectively reduces the amount of pollutants generated, is more environmentally friendly, and has a better thermal decomposition effect on the tribasic acid leachate with high decomposition efficiency, effectively improving the product yield. Attached Figure Description

[0023] Figure 1 A schematic diagram of the structure of an electrolytic furnace for thermally decomposing tribasic acid leachate according to an embodiment of the present invention;

[0024] Figure 2 for Figure 1 Schematic diagram of the gas distribution device;

[0025] Figure 3 for Figure 1 A top view of the structure of the electric heating element.

[0026] Explanation of icon numbers:

[0027] 1. Furnace body; 11. Discharge port; 2. Nozzle; 21. Injector gas inlet; 22. Raw material solution inlet; 23. Spray hole; 3. Electric heating tube; 31. Inner perimeter area; 4. Hand hole; 5. Sight glass; 6. Knob; 7. Baffle plate; 81. Gas distribution plate; 82. First purge gas pipe; 83. Cylinder; 84. Second purge gas pipe; 9. Tube plate.

[0028] The realization of the purpose, functional features and advantages of this utility model will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0029] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present utility model.

[0030] It should be noted that if the embodiments of this utility model involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indicators will also change accordingly.

[0031] Furthermore, if the embodiments of this utility model involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the use of "and / or" or "and / or" throughout the text includes three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.

[0032] Please see Figures 1 to 3 This utility model provides an electrolytic furnace for thermally decomposing a tribasic acid leachate, comprising: a furnace body 1, a nozzle 2, and at least one electric heating tube 3. The side wall of the furnace body 1 is provided with a discharge port 11. The nozzle 2 is located at the bottom of the furnace body 1 and has a feed end and a nozzle hole 23 arranged opposite to each other. The feed end is provided with an ejector gas inlet 21 and a raw material solution inlet 22. The nozzle hole 23 is located inside the furnace body 1. A plurality of electric heating tubes 3 are arranged inside the furnace body 1 above the nozzle hole 23. The plurality of electric heating tubes 3 are arranged close to the inner wall of the furnace body 1 and are arranged in a ring. The plurality of electric heating tubes 3 define an inner perimeter region 31, which is correspondingly arranged with respect to the nozzle hole 23.

[0033] In the technical solution of this invention, compressed air (0.5-1.0 MPa) enters the nozzle 2 through the ejector gas inlet 21, and the ternary acid leaching solution enters the nozzle 2 through the raw material solution inlet 22. The mass flow ratio of compressed air to ternary acid leaching solution is 0.5-2:1. Under the action of compressed air as the ejector gas flow, the ternary acid leaching solution is sprayed out from the nozzle 23 to form a mist. In the technical solution of this utility model, the nozzle 2 is preferably a siphon nozzle 2. It can be understood that an electric heating tube is a device that converts electrical energy into heat energy.

[0034] The mist-like raw material enters the inner region 31 enclosed by the electric heating tube 3, and the electric heating tube 3 keeps the temperature inside the furnace body 1 at 400-1000℃. Under the heating conditions, the water in the mist-like raw material evaporates rapidly, and the raw material is pyrolyzed to form oxide powder. The water vapor and oxide powder flow with the hot air flow to the discharge port 11 and are then discharged from the furnace body 1 for subsequent gas-solid separation treatment.

[0035] It should be noted that the furnace body 1 is vertically arranged, and the inner perimeter region 31 is located in the middle of the furnace body 1 and extends along the axial direction of the furnace body 1; wherein, the furnace body 1, the nozzle 2 and the inner perimeter region 31 are coaxially arranged, and the atomization angle α formed by the atomized material sprayed from the nozzle does not exceed 30°, so as to ensure that the atomized material sprayed from the nozzle 2 enters the inner perimeter region 31.

[0036] Specifically, each of the electric heating tubes 3 is a U-shaped electric heating tube 3, and each of the U-shaped electric heating tubes 3 is arranged along the axial direction of the furnace body 1.

[0037] To facilitate the installation of the electric heating tubes 3, in this embodiment of the invention, the electrolytic furnace further includes a tube plate 9, which is disposed in the upper part of the furnace body 1, and each of the electric heating tubes 3 is installed on the tube plate 9. Specifically, the open ends of each U-shaped electric heating tube 3 are installed on the tube plate 9, and the ends of the U-shaped electric heating tubes 3 penetrate the tube plate 9 for connection to the power supply line; wherein, multiple electric heating tubes 3 are connected in parallel.

[0038] To facilitate the discharge of pyrolysis products, there are multiple discharge ports 11, which are distributed along the axial direction of the furnace body 1. It is understood that the multiple discharge ports 11 are located below the tube sheet 9 and above the nozzles 23.

[0039] During the pyrolysis process, most of the generated oxide powder can be discharged from the furnace body 1 through the discharge port 11. A small portion of the oxide powder falls to the bottom of the furnace body 1, which is difficult to clean. To better collect this oxide powder, in this embodiment of the invention, the electrolytic furnace further includes a baffle plate 7. The baffle plate 7 is disposed in the lower part of the furnace body 1, and the nozzle 2 penetrates through the baffle plate 7. The spray hole 23 is located above the baffle plate 7. The powder falling during pyrolysis can fall onto the baffle plate 7, and the baffle plate 7 makes the material easier to clean.

[0040] To facilitate the cleaning of materials on the baffle plate 7, in a further embodiment of this utility model, a hand hole 4 is provided on the side wall of the furnace body 1 between the baffle plate 7 and the electric heating tube 3. Under normal circumstances, the hand hole 4 is in a closed state. When it is necessary to clean the materials on the baffle plate 7, the hand hole 4 is opened to facilitate the worker to clean the accumulated materials on the baffle plate 7.

[0041] To facilitate observation of whether the material accumulated on the baffle plate 7 has reached the point where it needs to be cleaned, and to facilitate observation of the pyrolysis of the material inside the furnace body 1, this embodiment of the invention further includes a sight glass 5. A sight glass opening is provided on the side wall of the furnace body 1, and the sight glass 5 is installed in the sight glass opening. The sight glass 5 facilitates the observation of the working conditions inside the furnace body 1 by the operators.

[0042] It is understood that there are multiple sight glasses 5, one of which is located above and adjacent to the baffle plate 7, in order to observe the powder accumulated on the baffle plate 7 and the spraying situation of the nozzle 2. The installation positions of the other sight glasses 5 can be determined according to the actual situation, and this application does not impose any restrictions.

[0043] To prevent the powder from agglomerating on the inner wall of the furnace body 1 after the pyrolysis reaction, in a further embodiment of this invention, the electrolytic furnace also includes a tapping device 6, which is disposed on the outer wall of the furnace body 1. The tapping device 6 can generate vibration to prevent the powder from agglomerating on the inner wall of the furnace body 1.

[0044] Specifically, the knocker 6 is at least one set, and multiple sets of the knocker 6 are arranged along the axial direction of the furnace body 1, and each set of the knocker 6 is distributed in a ring on the outer wall of the furnace body 1.

[0045] By adopting the above technical solution, multiple sets of knockers 6 are provided along the axial direction of the furnace body 1, and the multiple knockers 6 that make up each set of knockers 6 are distributed in a ring on the outer side wall of the furnace body 1 to achieve a better knocking vibration effect and effectively prevent the powder from agglomerating on the inner side wall of the furnace body 1.

[0046] To ensure that the atomized raw material ejected from nozzle 2 remains stably atomized, in a further embodiment of this utility model, the electrolytic furnace also includes a gas distribution device. The gas distribution device includes a gas distribution plate 81 and a first purging gas pipe 82. The gas distribution plate 81 is disposed inside the furnace body 1 below the baffle plate 7, and the first purging gas pipe 82 is disposed at the bottom of the furnace body 1, with the outlet end of the first purging gas pipe 82 connected to the bottom of the furnace body 1. The baffle plate 7 has a porous structure.

[0047] By adopting the above technical solution, compressed air (0.1~1.0MPa) enters the furnace body 1 through the first purge air pipe 82 and flows upward to the gas distribution plate 81. The gas distribution plate 81 is provided with multiple through holes to ensure a more uniform gas distribution. The gas flows above the baffle plate 7 through the porous structure on the baffle plate 7, so that the atomized raw material can be better maintained in an atomized state to ensure the pyrolysis effect. It can be understood that the diameter of the through holes on the gas distribution plate 81 is larger than the diameter of the holes on the baffle plate 7, and the diameter of the holes on the baffle plate 7 is smaller than the particle size of the oxide powder, so as to achieve uniform gas distribution while the baffle plate 7 can better receive the falling oxide powder. The first purge air pipe 82 is set vertically; the gas distribution plate 81 is set close to the baffle plate 7.

[0048] Furthermore, the gas distribution device also includes a cylinder 83 and a second purge gas pipe 84. The cylinder 83 is disposed between the gas distribution plate 81 and the bottom end of the furnace body 1, and the nozzle 2 passes through the cylinder 83, the gas distribution plate 81 and the baffle plate 7 in sequence. The second purge gas pipe 84 is disposed on the side wall of the furnace body 1 below the gas distribution plate 81, and the outlet end of the second purge gas pipe 84 extends into the cylinder 83.

[0049] It should be noted that perforations are provided in the middle of the air distribution plate 81 and the middle of the baffle plate 7, and the perforations on the air distribution plate 81, the perforations on the baffle plate 7, the cylinder 83, and the inner circumference area 31 are coaxially arranged; the inner cavity of the cylinder 83, the perforations on the air distribution plate 81, and the perforations on the baffle plate 7 are connected in sequence, so that while the nozzle 2 passes through the cylinder 83, the air distribution plate 81, and the baffle plate 7 in sequence, the purging gas in the inner cavity of the cylinder 83 can also flow upward relatively stably.

[0050] Compressed air (0.1-1.0 MPa) enters the inner cavity of the cylinder 83 through the second purge pipe 84 and flows upward. The resulting purge gas can blow away the powder near the nozzle 2.

[0051] It is understandable that the cylinder 83 is a hollow structure with openings at both the top and bottom. To ensure the purging effect, the outlet end of the second purging air pipe 84 is set upward; the lower surface of the baffle plate 7 is in contact with the upper surface of the air distribution plate 81.

[0052] The above description is merely an exemplary embodiment of the present utility model and does not limit the patent scope of the present utility model. Any equivalent structural transformations made based on the technical concept of the present utility model and the contents of the present utility model specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present utility model.

Claims

1. An electrolytic furnace for thermal decomposition of a ternary acid leachate, characterized by, include: The furnace body has a discharge port on its side wall; A nozzle, disposed at the bottom of the furnace body, has a feed end and a spray hole disposed opposite each other. The feed end is provided with an ejector gas inlet and a raw material solution inlet, and the spray hole is located inside the furnace body; and... At least one electric heating tube is disposed in the furnace body above the spray hole, and multiple electric heating tubes are disposed close to the inner wall of the furnace body and are arranged in a ring. The multiple electric heating tubes define an inner perimeter area, which is disposed corresponding to the spray hole.

2. The electrolytic furnace for thermal decomposition of ternary acid leaching solution according to claim 1, characterized in that, The electrolytic furnace also includes a baffle plate, which is disposed in the lower part of the furnace body, and the nozzle penetrates the baffle plate, with the nozzle located above the baffle plate.

3. The electrolytic furnace for thermal decomposition of ternary acid leaching solution according to claim 2, characterized in that, A hand hole is provided on the side wall of the furnace body between the baffle plate and the electric heating tube.

4. The electrolytic furnace for thermal decomposition of ternary acid leaching solution according to claim 2, characterized in that, The electrolytic furnace also includes a gas distribution device, which includes a gas distribution plate and a first purging gas pipe. The gas distribution plate is disposed in the furnace body below the baffle plate, and the first purging gas pipe is disposed at the bottom of the furnace body, with the outlet end of the first purging gas pipe connected to the bottom of the furnace body. The baffle plate is provided with a porous structure.

5. The electrolytic furnace for thermal decomposition of ternary acid leaching solution according to claim 4, characterized in that, The gas distribution device further includes a cylinder and a second purging gas pipe. The cylinder is disposed between the gas distribution plate and the bottom end of the furnace body, and the nozzle passes through the cylinder, the gas distribution plate and the baffle plate in sequence. The second purging gas pipe is disposed on the side wall of the furnace body below the gas distribution plate, and the outlet end of the second purging gas pipe extends into the cylinder.

6. The electrolytic furnace for thermal decomposition of ternary acid leaching solution according to claim 5, characterized in that, The outlet end of the second purge air pipe is positioned upwards.

7. The electrolytic furnace for thermal decomposition of ternary acid leaching solution according to claim 1, characterized in that, The electrolytic furnace also includes a hammer, which is disposed on the outer wall of the furnace body.

8. The electrolytic furnace for thermal decomposition of ternary acid leaching solution according to claim 7, characterized in that, The tapping device is at least one set, and multiple sets of the tapping devices are arranged along the axial direction of the furnace body, with each set of the tapping devices distributed in a ring on the outer wall of the furnace body.

9. The electrolytic furnace for thermal decomposition of ternary acid leaching solution according to claim 1, characterized in that, Each of the electric heating elements is a U-shaped electric heating element, and each of the U-shaped electric heating elements is arranged along the axial direction of the furnace body; and / or, There are multiple discharge ports, which are distributed along the axial direction of the furnace body.

10. The electrolytic furnace for thermally decomposing tribasic acid leachate as described in claim 1, characterized in that, The electrolytic furnace further includes a tube sheet disposed in the upper part of the furnace body, and each of the electric heating tubes is mounted on the tube sheet; and / or, A sight glass is installed on the side wall of the furnace body.

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