Battery industry NMP tail gas recovery device

Abstract

The utility model relates to the technical field of battery industry NMP tail gas treatment, and discloses a battery industry NMP tail gas recovery device which comprises a gas collection tank, a gas inlet pipe is connected to one side wall of the gas collection tank through a flange, two layers of fine filter cotton filter screens are arranged in the gas collection tank, one side of the upper end of the gas collection tank is connected with a first connecting pipe through a flange, and the other side of the upper end of the gas collection tank is connected with a second connecting pipe through a flange. A cooling tower is arranged at the end, away from the gas collecting tank, of the first connecting pipe, and a one-way valve is arranged on the first connecting pipe. By arranging the gas collecting tank and the fine filter cotton filter screen, waste gas generated in battery production can be pretreated, solid particles and a part of water in the waste gas are removed, and impurities in recycled NMP are reduced; and by arranging a return pipe and a draft fan, the filtered gas in the exhaust box can be sucked and returned into the cooling tower, and is condensed by the cooling tower and filtered by the exhaust box again, so that the NMP in the waste gas can be removed more thoroughly.

Description

Technical Field

[0001] The utility model belongs to the technical field of NMP tail gas treatment in battery industry, in particular to a NMP tail gas recovery device in battery industry. Background Art

[0002] In the production process of lithium batteries, NMP is an important auxiliary material used to fuse together various electrode materials such as positive electrode binder, active material and conductive agent, so that the binder is fully in contact with other materials and evenly distributed. However, NMP is highly volatile and has a certain impact on the environment and human health, so it needs to be processed and recycled. NMP is N-methylpyrrolidone, an organic substance with a chemical formula of C5H9NO. It is a colorless to light yellow transparent liquid with a slight ammonia smell. It is miscible with water in any proportion, soluble in ether, acetone and various organic solvents such as esters, halogenated hydrocarbons, aromatic hydrocarbons, and is completely miscible with almost all solvents.

[0003] In the existing battery industry NMP tail gas recovery process, in order to ensure that NMP is recovered more thoroughly, multiple condensation recovery equipment will be set up, which will increase the energy consumption of NMP tail gas recovery, and the increase in the number of equipment will also make it more prone to failure and the maintenance cost will be high. For this reason, a battery industry NMP tail gas recovery device is proposed here. Summary of the invention

[0004] In view of the above situation, in order to overcome the defects of the prior art, the utility model provides a battery industry NMP tail gas recovery device, which effectively solves the problems existing in the existing battery industry NMP tail gas recovery device.

[0005] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a battery industry NMP tail gas recovery device, comprising an air collecting box, an air intake pipe is connected to one side wall of the air collecting box through a flange, two layers of fine filter cotton screens are arranged in the air collecting box, a first connecting pipe is connected to one side of the upper end of the air collecting box through a flange, a cooling tower is arranged at one end of the first connecting pipe away from the air collecting box, a one-way valve is arranged on the first connecting pipe, a cooling condenser is arranged on one side wall of the cooling tower, the annular condensing pipe of the cooling condenser extends into the cooling tower, and the middle part of the upper end of the cooling tower is connected to the first connecting pipe through a flange. A second connecting pipe is connected with a flange, and an exhaust box is arranged at one end of the second connecting pipe away from the cooling tower, and two layers of activated carbon filters are arranged in the exhaust box. An exhaust pipe is arranged on one side of the upper end of the exhaust box, and a first valve is arranged on the exhaust pipe. A return pipe is connected to the upper end of the exhaust box located on one side of the exhaust pipe through a flange, and an exhaust fan is arranged on the return pipe. The return pipe is connected to the side wall of the cooling tower through a flange at one end away from the exhaust box, and a recovery pipe is arranged on the side wall of the cooling tower below the return pipe, and a second valve is arranged on the upper end of the recovery pipe.

[0006] Preferably, the two fine cotton filters are overlapped with the inner wall of the air collecting box, the end of the first connecting pipe away from the air collecting box is connected to the side wall of the cooling tower through a flange, and the one-way valve is connected to the first connecting pipe through a flange. The NMP mixed gas generated by battery production is sent into the air collecting box by the exhaust fan through the air inlet pipe. The two layers of fine cotton filters will filter the gas entering the air collecting box to remove solid particles and some moisture in the gas. Thereafter, the filtered gas will enter the cooling tower through the first connecting pipe. The one-way valve can prevent the gas in the cooling tower from flowing back to the air collecting box.

[0007] Preferably, the cooling condenser is connected to the side wall of the cooling tower by bolts, the end of the second connecting pipe away from the cooling tower is connected to the side wall of the exhaust box by a flange, and the two activated carbon filters are overlapped with the inner wall of the exhaust box. The cooling condenser can use cooling water and chilled water coils to condense the NMP in the cooling tower from the air into liquid, which drips to the bottom end of the cooling tower. The uncondensed gas will continue to enter the exhaust box through the second connecting pipe. At this time, the first valve is in a closed state, and the gas entering the exhaust box will be adsorbed and filtered by the two layers of activated carbon filters to further remove NMP in the exhaust gas. After being used for a period of time, the activated carbon filter can be regenerated and recycled by heating or chemical agents to save costs.

[0008] Preferably, the lower end of the exhaust pipe is connected to the upper end of the exhaust box via a flange, and the first valve is connected to the exhaust pipe via threads.

[0009] Preferably, the exhaust fan is connected to the reflux pipe via a flange, and the exhaust direction of the exhaust fan is from top to bottom. When working, the exhaust fan can suck the filtered gas in the exhaust box and return it to the cooling tower, and then pass through condensation in the cooling tower and filtration in the exhaust box again. Such a cycle can remove NMP in the exhaust gas more thoroughly.

[0010] Preferably, the recovery pipe is connected to the side wall of the cooling tower by a flange, and the second valve is connected to the recovery pipe by a thread. After a certain amount of NMP condensate accumulates in the cooling tower, the second valve can be opened to discharge the NMP gas in the cooling tower through the recovery pipe for recovery. After each cycle, the first valve on the exhaust pipe can be opened to discharge the filtered air in the exhaust box through the exhaust pipe.

[0011] Compared with the prior art, the beneficial effects of the utility model are:

[0012] In the battery industry NMP tail gas recovery device, by setting up a gas collecting box and a fine filter cotton filter, the waste gas generated by battery production can be pre-treated to remove solid particles and a part of moisture in the waste gas, and reduce impurities in the recovered NMP; the reflux pipe and the exhaust fan are set up so that the filtered gas in the exhaust box can be sucked back into the cooling tower, and then condensed in the cooling tower and filtered in the exhaust box again. Such a cycle can remove NMP in the waste gas more thoroughly; the device only uses one condensation tower to circulate and condense the waste gas, which can reduce the use cost and maintenance cost of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0014] Figure 1 It is a schematic diagram of the structure of the utility model;

[0015] Figure 2 It is a front cross-sectional view of the gas collecting box in the utility model;

[0016] Figure 3 It is a front cross-sectional view of the exhaust box in the utility model;

[0017] In the figure: 1. Air collecting box; 2. Air inlet pipe; 3. Fine filter cotton filter; 4. First connecting pipe; 5. Cooling tower; 6. One-way valve; 7. Cooling condenser; 8. Second connecting pipe; 9. Exhaust box; 10. Activated carbon filter; 11. Exhaust pipe; 12. First valve; 13. Reflux pipe; 14. Exhaust fan; 15. Recovery pipe; 16. Second valve. DETAILED DESCRIPTION

[0018] The technical solutions in the embodiments of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all of the embodiments; based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the utility model.

[0019] In this embodiment, Figure 1-3The utility model includes an air collecting box 1, an air inlet pipe 2 is connected to one side wall of the air collecting box 1 through a flange, two layers of fine filter cotton filter screens 3 are arranged in the air collecting box 1, a first connecting pipe 4 is connected to one side of the upper end of the air collecting box 1 through a flange, a cooling tower 5 is arranged at one end of the first connecting pipe 4 away from the air collecting box 1, a one-way valve 6 is arranged on the first connecting pipe 4, a cooling condenser 7 is arranged on one side wall of the cooling tower 5, an annular condensing pipe of the cooling condenser 7 extends into the cooling tower 5, a second connecting pipe 8 is connected to the middle part of the upper end of the cooling tower 5 through a flange, and the second connecting pipe 8 is away from the end of the cooling tower 5. An exhaust box 9 is provided at one end of the cooling tower 5, and two layers of activated carbon filters 10 are provided in the exhaust box 9. An exhaust pipe 11 is provided on one side of the upper end of the exhaust box 9, and a first valve 12 is provided on the exhaust pipe 11. The upper end of the exhaust box 9 located on one side of the exhaust pipe 11 is connected with a return pipe 13 through a flange, and an exhaust fan 14 is provided on the return pipe 13. The end of the return pipe 13 away from the exhaust box 9 is connected to the side wall of the cooling tower 5 through a flange, and a recovery pipe 15 is provided on the side wall of the cooling tower 5 below the return pipe 13, and a second valve 16 is provided on the upper end of the recovery pipe 15.

[0020] Among them, two fine filter cotton screens 3 are overlapped with the inner wall of the gas collecting box 1, the end of the first connecting pipe 4 away from the gas collecting box 1 is connected to the side wall of the cooling tower 5 through a flange, and the one-way valve 6 is connected to the first connecting pipe 4 through a flange. The NMP mixed gas generated by the battery production is sent into the gas collecting box 1 by the exhaust fan through the air inlet pipe 2. The two layers of fine filter cotton screens 3 will filter the gas entering the gas collecting box 1 to remove solid particles and some moisture in the gas. Then the filtered gas will enter the cooling tower 5 through the first connecting pipe 4, and the one-way valve 6 can prevent the gas in the cooling tower 5 from flowing back to the gas collecting box 1.

[0021] Among them, the cooling condenser 7 is connected to the side wall of the cooling tower 5 by bolts, the second connecting pipe 8 is connected to the side wall of the exhaust box 9 by a flange at one end away from the cooling tower 5, and the two activated carbon filters 10 are overlapped with the inner wall of the exhaust box 9. The cooling condenser 7 can use cooling water and chilled water coils to condense the NMP in the cooling tower 5 from the air into liquid, and drip to the bottom end of the cooling tower 5. The uncondensed gas will continue to enter the exhaust box 9 through the second connecting pipe 8. At this time, the first valve 12 is in a closed state, and the gas entering the exhaust box 9 will be adsorbed and filtered by the two layers of activated carbon filters 10 to further remove NMP in the exhaust gas. After being used for a period of time, the activated carbon filter 10 can be regenerated and recycled by heating or chemical agents to save costs.

[0022] Among them, the lower end of the exhaust pipe 11 is connected to the upper end of the exhaust box 9 through a flange, the first valve 12 is connected to the exhaust pipe 11 through a threaded connection, the exhaust fan 14 is connected to the return pipe 13 through a flange, and the exhaust direction of the exhaust fan 14 is from top to bottom. When the exhaust fan 14 is working, it can suck the filtered gas in the exhaust box 9 back into the cooling tower 5, and then pass through the condensation of the cooling tower 5 and the filtration of the exhaust box 9 again. Such a cycle can remove NMP in the exhaust gas more thoroughly.

[0023] The recovery pipe 15 is connected to the side wall of the cooling tower 5 by a flange, and the second valve 16 is connected to the recovery pipe 15 by a thread. After a certain amount of NMP condensate accumulates in the cooling tower 5, the second valve 16 can be opened to discharge the NMP gas in the cooling tower 5 through the recovery pipe 15 for recovery.

[0024] Working principle: The device uses an external power supply and is controlled by an external control device to work. The NMP mixed gas generated by battery production is sent into the gas collecting box 1 by the exhaust fan through the air inlet pipe 2. The two-layer fine filter cotton filter 3 will filter the gas entering the gas collecting box 1 to remove solid particles and part of the water in the gas. Then the filtered gas will enter the cooling tower 5 through the first connecting pipe 4. The cooling condenser 7 can use cooling water and chilled water coils to condense the NMP in the cooling tower 5 from the air into liquid and drip to the bottom of the cooling tower 5. The uncondensed gas will continue to enter the exhaust box 9 through the second connecting pipe 8. At this time, the first valve 12 is closed and enters The gas in the exhaust box 9 will be adsorbed and filtered by the two layers of activated carbon filter 10 to further remove NMP in the exhaust gas. The exhaust fan 14 can suck the filtered gas in the exhaust box 9 back to the cooling tower 5 when working, and then pass through the condensation of the cooling tower 5 and the filtration of the exhaust box 9 again. In this cycle, the NMP in the exhaust gas can be removed more thoroughly. After a certain amount of NMP condensate accumulates in the cooling tower 5, the second valve 16 can be opened to discharge the NMP gas in the cooling tower 5 through the recovery pipe 15 for recovery. After each cycle, the first valve 12 on the exhaust pipe 11 can be opened to discharge the filtered air in the exhaust box 9 through the exhaust pipe 11.

[0025] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0026] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A battery industry NMP tail gas recovery device, comprising a gas collecting box (1), characterized in that: An air inlet pipe (2) is connected to one side wall of the air collecting box (1) via a flange, two layers of fine cotton filter screens (3) are arranged in the air collecting box (1), a first connecting pipe (4) is connected to one side of the upper end of the air collecting box (1) via a flange, a cooling tower (5) is arranged at one end of the first connecting pipe (4) away from the air collecting box (1), a one-way valve (6) is arranged on the first connecting pipe (4), a cooling condenser (7) is arranged on one side wall of the cooling tower (5), the annular condensing pipe of the cooling condenser (7) extends into the cooling tower (5), a second connecting pipe (8) is connected to the middle part of the upper end of the cooling tower (5) via a flange, and the second connecting pipe (8) is arranged at one end away from the cooling tower (5). An exhaust box (9) is provided, wherein two layers of activated carbon filters (10) are arranged in the exhaust box (9), an exhaust pipe (11) is arranged on one side of the upper end of the exhaust box (9), a first valve (12) is arranged on the exhaust pipe (11), the upper end of the exhaust box (9) located on one side of the exhaust pipe (11) is connected to a return pipe (13) through a flange, an exhaust fan (14) is arranged on the return pipe (13), the end of the return pipe (13) away from the exhaust box (9) is connected to the side wall of the cooling tower (5) through a flange, a recovery pipe (15) is arranged on the side wall of the cooling tower (5) below the return pipe (13), and a second valve (16) is arranged on the upper end of the recovery pipe (15).

2. The battery industry NMP tail gas recovery device according to claim 1, characterized in that: The two fine filter cotton screens (3) are both overlapped with the inner wall of the air collecting box (1), the end of the first connecting pipe (4) away from the air collecting box (1) is connected to the side wall of the cooling tower (5) through a flange, and the one-way valve (6) is connected to the first connecting pipe (4) through a flange.

3. The battery industry NMP tail gas recovery device according to claim 1, characterized in that: The cooling condenser (7) is connected to the side wall of the cooling tower (5) by bolts, the end of the second connecting pipe (8) away from the cooling tower (5) is connected to the side wall of the exhaust box (9) by a flange, and the two activated carbon filters (10) are overlapped with the inner wall of the exhaust box (9).

4. The battery industry NMP tail gas recovery device according to claim 1, characterized in that: The lower end of the exhaust pipe (11) is connected to the upper end of the exhaust box (9) via a flange, and the first valve (12) is connected to the exhaust pipe (11) via threads.

5. The battery industry NMP tail gas recovery device according to claim 1, characterized in that: The exhaust fan (14) is connected to the return pipe (13) via a flange, and the exhaust direction of the exhaust fan (14) is from top to bottom.

6. The battery industry NMP tail gas recovery device according to claim 1, characterized in that: The recovery pipe (15) is connected to the side wall of the cooling tower (5) via a flange, and the second valve (16) is connected to the recovery pipe (15) via a thread.

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