Wastewater treatment device and lithium battery preparation system

Abstract

The utility model discloses a wastewater treatment device. The wastewater treatment device comprises a first filter press, a drying mechanism, a first liquid storage tank, an oxidation mechanism and a second filter press, the drying mechanism is arranged at the downstream of the first filter press; the first liquid storage tank is arranged at the downstream of the drying mechanism and is used for storing distilled water generated by the drying mechanism; the oxidation mechanism is arranged at the downstream of the first liquid storage tank and is used for carrying out oxidative degradation on the distilled water in the first liquid storage tank; and the second filter press is arranged at the downstream of the oxidation mechanism. After positive electrode slurry wastewater is subjected to filter pressing, filter residues are subjected to hazardous waste treatment, filtrate enters the drying mechanism and is dried at low temperature in the drying mechanism, generated solid waste is also subjected to hazardous waste treatment, generated distilled water enters the first liquid storage tank to be stored, and then the distilled water is input into the oxidation mechanism to be subjected to oxidative degradation; and after degradation, inputting into a second filter press for filter pressing treatment. The wastewater treatment device can be used for treating the positive electrode slurry wastewater, and is relatively short in process chain and relatively low in cost. The utility model further discloses a lithium battery preparation system.

Description

Technical Field

[0001] This application belongs to the technical field of wastewater treatment equipment, specifically relating to a wastewater treatment device and a lithium battery manufacturing system. Background Technology

[0002] The lithium battery manufacturing process includes the production and recycling of cathode materials. Cathode slurry wastewater is generated during the production and recycling of cathode materials. Cathode slurry wastewater usually contains N-methylpyrrolidone (NMP), water, conductive agents, trace amounts of nickel, cobalt, manganese, lithium and polyvinylidene fluoride (PVDF), etc., and is characterized by high salt, high COD, high ammonia nitrogen and high concentration of organic matter.

[0003] Currently, cathode slurry wastewater is typically pretreated and then distilled to recover NMP, followed by high-temperature catalytic oxidation, electro-oxidation, and biochemical treatment before being discharged in compliance with standards. However, due to the small volume of cathode slurry wastewater, which is only a few tons or tens of tons per day, distillation recovery would result in a long process chain and high treatment costs. Utility Model Content

[0004] The technical problem to be solved by this application is that the treatment cost of existing cathode slurry wastewater is relatively high. In order to solve this technical problem, a wastewater treatment device and a lithium battery preparation system that can treat cathode slurry wastewater at a low cost are provided.

[0005] The technical solution proposed in this application is as follows:

[0006] A wastewater treatment device, comprising:

[0007] First filter press;

[0008] The drying mechanism is located downstream of the first filter press;

[0009] The first storage tank is located downstream of the drying mechanism and is used to store the distilled water produced by the drying mechanism.

[0010] An oxidation mechanism is located downstream of the first storage tank and is used to oxidize and degrade the distilled water in the first storage tank.

[0011] The second filter press is located downstream of the oxidation mechanism.

[0012] The wastewater treatment device can be used for the treatment of positive electrode slurry wastewater, and has a short process chain and low cost compared with a rectification method.

[0013] Further, the wastewater treatment device further comprises a raw water tank and a first conveying pump, the raw water tank is used for storing raw water, and the first conveying pump is connected with the raw water tank and the first filter press.

[0014] Further, the wastewater treatment device further comprises a second conveying pump, the second conveying pump is connected with the first liquid storage tank and the drying mechanism, so as to pump the distilled water in the first liquid storage tank to the drying mechanism.

[0015] Further, the wastewater treatment device further comprises a second liquid storage tank, the second liquid storage tank is arranged between the first filter press and the drying mechanism, and the second liquid storage tank is used for storing the filtrate generated by the first filter press.

[0016] The second conveying pump is also connected with the second liquid storage tank, and the second conveying pump can be alternately communicated with the first liquid storage tank and the second liquid storage tank.

[0017] Further, the wastewater treatment device further comprises a first control valve and a second control valve, the first control valve is arranged between the first liquid storage tank and the second conveying pump, and the second control valve is arranged between the second liquid storage tank and the second conveying pump.

[0018] Further, the wastewater treatment device further comprises a third conveying pump, the third conveying pump is connected with the first liquid storage tank and the oxidation mechanism.

[0019] Further, the wastewater treatment device further comprises an adsorption tower, the adsorption tower is connected with the oxidation mechanism, and is used for adsorbing and exhausting the gas generated by the oxidation mechanism.

[0020] Further, the wastewater treatment device further comprises a sedimentation tank, the sedimentation tank is arranged between the oxidation mechanism and the second filter press, the sedimentation tank is used for performing sedimentation treatment on the distilled water subjected to oxidation degradation, and the second filter press is used for performing filter pressing on the sediment in the sedimentation tank.

[0021] Further, the wastewater treatment device further comprises a fourth conveying pump, the fourth conveying pump is connected with the sedimentation tank and the second filter press.

[0022] A lithium battery preparation system comprising the wastewater treatment device as described above. BRIEF DESCRIPTION OF DRAWINGS

[0023] The accompanying drawings are included to provide a further understanding of the present application, and are incorporated in and constitute a part of the specification, illustrate embodiments of the present application and explain the principles of the present application, and are used to explain the present application together with the embodiments of the present application, and do not constitute a limitation on the present application.

[0024] Figure 1 The structural schematic diagram of the wastewater treatment device provided by an embodiment of the present application is shown.

[0025] EXPLANATION OF REFERENCE NUMERALS

[0026] 11, first filter press; 12, drying mechanism; 13, first liquid storage tank; 14, oxidation mechanism; 15, second filter press; 16, raw water tank; 17, first delivery pump; 18, raw water valve; 19, second delivery pump; 20, second liquid storage tank; 21, first control valve; 22, second control valve; 23, residue discharge valve; 24, third delivery pump; 25, third control valve; 26, adsorption tower; 27, exhaust valve; 28, sedimentation tank; 29, fourth delivery pump; 30, fourth control valve; 31, fifth control valve. DETAILED DESCRIPTION

[0027] The technical solutions in the embodiments of the present application will be described clearly and completely in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0028] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise" and the like indicate the orientation or positional relationship shown in the drawings, and are only used to facilitate the description of the present application and simplify the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0029] In one aspect, the application provides a wastewater treatment device, which comprises a first filter press 11, a drying mechanism 12, a first liquid storage tank 13, an oxidation mechanism 14, and a second filter press 15. The drying mechanism 12 is arranged downstream of the first filter press 11, the first liquid storage tank 13 is arranged downstream of the drying mechanism 12, the oxidation mechanism 14 is arranged downstream of the first liquid storage tank 13, and the second filter press 15 is arranged downstream of the oxidation mechanism 14.

[0030] The first filter press 11 is used to filter the raw water (e.g., positive electrode slurry wastewater) by pressure filtration, and the filtrate after pressure filtration is input into the drying mechanism 12. The drying mechanism 12 is preferably a low-temperature drying mechanism 12, and the distilled water generated by low-temperature drying in the drying mechanism 12 is stored in the first liquid storage tank 13. Next, the distilled water in the first liquid storage tank 13 is obtained by the oxidation mechanism 14 and is subjected to oxidative degradation to degrade the organic matter in the water; and the solution after oxidative degradation is subjected to pressure filtration by the second filter press 15, and both the filter residue and the filtrate can be discharged up to standard.

[0031] By using the above wastewater treatment device, after the positive electrode slurry wastewater is filtered by pressure filtration, the filter residue is disposed as hazardous waste, the filtrate enters the drying mechanism 12 and is subjected to low-temperature drying in the drying mechanism 12, and the solid waste generated is also disposed as hazardous waste, the distilled water generated is stored in the first liquid storage tank 13, and then is input into the oxidation mechanism 14 for oxidative degradation to degrade the oxidants in the water, and after degradation, is input into the second filter press 15 for pressure filtration treatment. The wastewater treatment device can be used for the disposal of positive electrode slurry wastewater, and the process chain is relatively short, and compared with the way of using rectification, the cost is lower.

[0032] In one embodiment, the wastewater treatment device further comprises a raw water tank 16 and a first delivery pump 17. The raw water tank 16 is used to store raw water, such as the above-mentioned positive electrode slurry wastewater, and the first delivery pump 17 is connected with the raw water tank 16 and the first filter press 11 to pump the raw water in the raw water tank 16 to the first filter press 11. Further, the wastewater treatment device further comprises a raw water valve 18, which is arranged between the raw water tank 16 and the first filter press 11, such as the embodiment shown in the figure, for controlling the on-off between the raw water tank 16 and the first filter press 11. In this way, the raw water valve 18 can be opened when the amount of raw water in the raw water tank 16 reaches a certain degree, and then the raw water is pumped into the first filter press 11 by the first delivery pump 17. Figure 1

[0033] In one embodiment, the wastewater treatment device further comprises a second delivery pump 19, which is connected with the first liquid storage tank 13 and the drying mechanism 12 to pump the distilled water in the first liquid storage tank 13 into the drying mechanism 12. In this way, the distilled water in the first liquid storage tank 13 can be pumped into the drying mechanism 12 by the second delivery pump 19, so as to realize the cleaning of the drying mechanism 12 and avoid the scaling of the drying mechanism 12.​

[0034] Further, the second delivery pump 19 is also connected with the first filter press 11 and can be communicated with the first filter press 11 and the first storage tank 13 alternately. When the filtrate of the first filter press 11 needs to be delivered to the drying mechanism 12, the second delivery pump 19 is communicated with the first filter press 11; when the drying mechanism 12 needs to be cleaned, the second delivery pump 19 can be communicated with the first storage tank 13.

[0035] In actual application, the wastewater treatment device further comprises a second storage tank 20, which is arranged between the first filter press 11 and the drying mechanism 12 and is used for storing the filtrate generated by the first filter press 11. The second delivery pump 19 is also connected with the second storage tank 20, and the second delivery pump 19 can be communicated with the first storage tank 13 and the second storage tank 20 alternately.

[0036] Preferably, the wastewater treatment device further comprises a first control valve 21 and a second control valve 22. The first control valve 21 is arranged between the first storage tank 13 and the second delivery pump 19 and is used for controlling the on-off between the first storage tank 13 and the second delivery pump 19. The second control valve 22 is arranged between the second storage tank 20 and the second delivery pump 19 and is used for controlling the on-off between the second storage tank 20 and the second delivery pump 19. Specifically, when the wastewater treatment device is working normally, the first control valve 21 is closed, the second control valve 22 is opened, and the second delivery pump 19 pumps the filtrate in the second storage tank 20 to the drying mechanism 12; when the drying mechanism 12 needs to be cleaned, the first control valve 21 is opened, the second control valve 22 is closed, and the second delivery pump 19 pumps the distilled water in the first storage tank 13 to the drying mechanism 12.

[0037] As for the drying mechanism 12, as described above, the drying mechanism 12 is a low-temperature drying mechanism 12. Specifically, a low-pressure steam is used to provide a heat source, and the liquid in the filtrate is boiled and evaporated at a temperature of 45°C in a pressure environment with a pressure of -0.09 MPa, the solid waste obtained by evaporation drying is disposed as hazardous waste, and the distilled water after condensation of the steam is input into the first storage tank 13. In addition, a slag discharge valve 23 can be arranged at the slag discharge port of the drying mechanism 12 to control the slag discharge of the drying mechanism 12. It should be noted that, in the embodiment, the operation mode of the drying mechanism 12 is sequencing batch treatment.

[0038] In one embodiment, the wastewater treatment device further comprises a third delivery pump 24, which is connected with the first storage tank 13 and the oxidation mechanism 14 and is used for pumping the distilled water in the first storage tank 13 to the oxidation mechanism 14. In actual application, the wastewater treatment device further comprises a third control valve 25, which is arranged between the first storage tank 13 and the oxidation mechanism 14, for example Figure 1The second control valve 22 is arranged between the first storage tank 13 and the third conveying pump 24, and is used to control the connection and disconnection between the first storage tank 13 and the oxidation mechanism 14.

[0039] In an embodiment, the wastewater treatment device further comprises an adsorption tower 26, which is connected with the oxidation mechanism 14, in particular, connected with the gas outlet of the oxidation mechanism 14, and is used to adsorb nitrogen oxides and carbon oxides in the gas generated in the oxidation mechanism 14, and then discharge the adsorbed gas, so as to avoid gas pollution. Further, an exhaust valve 27 is arranged between the adsorption tower 26 and the oxidation mechanism 14, so as to control the discharge of the exhaust gas in the oxidation mechanism 14.

[0040] In an embodiment, the wastewater treatment device further comprises a sedimentation tank 28, which is arranged between the oxidation mechanism 14 and the second pressure filter 15, and is used to perform sedimentation treatment on the distilled water subjected to oxidation degradation, and the second pressure filter 15 is used to perform pressure filtration on the sediment in the sedimentation tank 28.

[0041] It should be noted that in the present embodiment, the oxidation mechanism 14 is a Fenton mechanism, an electro-Fenton mechanism or other mechanisms involving Fenton reaction, and the sedimentation tank 28 needs to be arranged after oxidation degradation. In other embodiments, when the oxidation mechanism 14 adopts an oxidation degradation process such as ozone or photocatalysis, the sedimentation tank 28 can not be arranged, and the oxidation mechanism 14 directly inputs the distilled water subjected to oxidation degradation into the second pressure filter 15.

[0042] Further, the wastewater treatment device further comprises a fourth conveying pump 29, which is connected with the sedimentation tank 28 and the second pressure filter 15, so as to pump the sediment in the sedimentation tank 28 to the second pressure filter 15. It can be understood that the sediment in the sedimentation tank 28 is slurry with certain fluidity, and after pressure filtration by the second pressure filter 15, the liquid waste and the liquid waste can be discharged separately. It should be noted that the organic matter in the distilled water subjected to oxidation degradation is degraded, so the supernatant in the sedimentation tank 28, the filtrate and the filter residue generated by the second pressure filter 15 can be discharged by conventional disposal, without the need for hazardous waste disposal.

[0043] Similarly, the wastewater treatment device further comprises a fourth control valve 30 and a fifth control valve 31. The fourth control valve 30 is arranged between the oxidation mechanism 14 and the sedimentation tank 28, so as to control the connection and disconnection between the oxidation mechanism 14 and the sedimentation tank 28. The fifth control valve 31 is arranged between the sedimentation tank 28 and the second pressure filter 15, for example Figure 1 between the sedimentation tank 28 and the fourth conveying pump 29, so as to control the connection and disconnection between the sedimentation tank 28 and the second pressure filter 15.

[0044] In order to facilitate understanding of the technical scheme of the present application, the process flow of the wastewater treatment device in the above embodiment is described as follows:

[0045] The positive slurry wastewater is transported into the raw water tank 16 through a pipeline. When a certain amount of wastewater is reached, the raw water valve 18 is opened, and the first delivery pump 17 pumps the wastewater to the first filter press 11. The filter residue generated by the filter press is disposed of as hazardous waste, and the filtrate enters the second liquid storage tank 20. When the amount of filtrate in the second liquid storage tank 20 reaches a certain amount (e.g., ≥ 9 m³), the second control valve 22 is opened (the first control valve 21 is in a closed state), and the second delivery pump 19 pumps the filtrate to the drying mechanism 12 for low-temperature drying treatment. The solid waste generated by the drying mechanism 12 is disposed of as hazardous waste, and the distilled water generated is introduced into the first liquid storage tank 13.

[0046] Next, the distilled water in the first liquid storage tank 13 is pumped to the oxidation mechanism 14 by the third delivery pump 24 for oxidation degradation. The waste gas generated during the oxidation degradation process is adsorbed by the adsorption tower 26 and then emptied. The liquid generated is introduced into the sedimentation tank 28 for sedimentation. The supernatant after sedimentation in the sedimentation tank 28 can be discharged, and the sediment is pumped to the second filter press 15 by the fourth delivery pump 29 for filter pressing treatment. The filter residue and the filtrate generated by the second filter press 15 can be discharged separately.

[0047] When the drying mechanism 12 needs to be cleaned, the second control valve 22 is closed, the first control valve 21 is opened, and the second delivery pump 19 pumps the distilled water in the first liquid storage tank 13 to the drying mechanism 12.

[0048] On the other hand, the present application also provides a lithium battery preparation system, which comprises the wastewater treatment device in the above-mentioned embodiments and is used for treating positive slurry wastewater generated in the production and recovery of positive electrode materials.

[0049] In summary, the wastewater treatment device and the lithium battery preparation system provided by the present application have at least the following advantages:

[0050] 1. The positive slurry wastewater can be treated, and the process chain is short, the land occupation area is small, and the cost is low;

[0051] 2. Through filter pressing treatment, only a small amount of solid waste needs to be disposed of as hazardous waste, which reduces the amount of waste for hazardous waste disposal and reduces the cost of hazardous waste disposal;

[0052] 3. The drying mechanism 12 is cleaned by distilled water, which avoids scaling of the drying mechanism 12, prolongs the service life, and improves the reliability of use.

[0053] Although the embodiments of the present application have been shown and described, it will be understood by those of ordinary skill in the art that various changes, modifications, replacements and variations can be made to these embodiments without departing from the principles and spirits of the present application, and the scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A wastewater treatment apparatus, characterized by, The wastewater treatment device comprises: a first filter press; a drying mechanism arranged downstream of the first filter press; a first liquid storage tank arranged downstream of the drying mechanism, for storing distilled water generated by the drying mechanism; an oxidation mechanism arranged downstream of the first liquid storage tank, for oxidizing and degrading the distilled water in the first liquid storage tank; a second filter press arranged downstream of the oxidation mechanism.

2. The wastewater treatment device according to claim 1, characterized by The wastewater treatment device further comprises a raw water tank for storing raw water, and a first conveying pump connected to the raw water tank and the first filter press.

3. The wastewater treatment device according to claim 1, characterized by The wastewater treatment device further comprises a second conveying pump connected to the first liquid storage tank and the drying mechanism, for pumping the distilled water in the first liquid storage tank to the drying mechanism.

4. The wastewater treatment device according to claim 3, characterized by The wastewater treatment device further comprises a second liquid storage tank arranged between the first filter press and the drying mechanism, for storing filtrate generated by the first filter press. The second conveying pump is further connected to the second liquid storage tank, and the second conveying pump can alternately communicate with the first liquid storage tank and the second liquid storage tank.

5. The wastewater treatment device of claim 4, wherein The wastewater treatment device further comprises a first control valve arranged between the first liquid storage tank and the second conveying pump, and a second control valve arranged between the second liquid storage tank and the second conveying pump.

6. The wastewater treatment device of claim 1, wherein The wastewater treatment device further comprises a third conveying pump connected to the first liquid storage tank and the oxidation mechanism.

7. The wastewater treatment device of claim 1, wherein The wastewater treatment device further comprises an adsorption tower connected to the oxidation mechanism, for adsorbing and exhausting gas generated by the oxidation mechanism.

8. The wastewater treatment device of claim 1, wherein The wastewater treatment device further comprises a sedimentation tank arranged between the oxidation mechanism and the second filter press, for performing sedimentation treatment on the distilled water subjected to oxidation and degradation, and the second filter press is used for performing filter pressing on the sediment in the sedimentation tank.

9. The wastewater treatment device of claim 8, wherein, The wastewater treatment device further comprises a fourth conveying pump connected to the sedimentation tank and the second filter press.

10. A lithium battery production system, characterized by, The wastewater treatment device comprises the wastewater treatment device according to any one of claims 1-9.

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