A lithium battery production waste gas treatment and recovery device

Abstract

The present invention relates to the technical field of waste gas treatment, and specifically discloses a waste gas treatment and recovery device for lithium battery production, including a waste gas treatment and recovery device for lithium battery production, including a condenser, the condenser is used to condense high-concentration NMP after distillation; a gas-liquid separation box, the top of the gas-liquid separation box is fixedly connected to the condensation outlet of the condenser through a branch pipe, and a gas-liquid separation net is arranged between the top wall and the bottom wall of the gas-liquid separation box; a liquid collecting tank, the top of the liquid collecting tank is provided with two liquid inlets, the bottom end of the gas-liquid separation box is fixedly connected to the adjacent liquid inlets through a branch pipe, and the bottom end of the liquid collecting tank is provided with a discharge structure; a zeolite adsorption concentration rotor, the desorption zone of the zeolite adsorption concentration rotor is provided with a gas collecting pipe; and a heat exchange box. The present invention has a dual waste gas recovery structure of condensation and rotor adsorption, improves the recovery rate of NMP, has waste heat recovery technology, and reduces recovery energy.

Description

Technical Field

[0001] The present invention relates to the technical field of waste gas treatment, and in particular to a waste gas treatment and recovery device for lithium battery production. Background Art

[0002] NMP is an excellent advanced solvent, widely used in petrochemical, clothing medicine, medicine, electronic materials, lithium battery manufacturing and other fields. The waste gas containing NMP generated in the production process needs to be recovered or treated. N-methylpyrrolidone has many advantages such as high flash point and good safety. In the manufacturing process of lithium-ion batteries, polymer materials need to be dissolved in organic solvents and then coated on the surface of electrode materials. NMP is widely used as an organic solvent in the lithium battery manufacturing industry. The polymer material is dissolved in NMP and coated on the surface of the electrode material, and then dried. During the drying process, NMP will all turn into gas and be discharged in large quantities through the fan. If the discharged waste gas containing a large amount of NMP is not recycled, it will not only cause a huge waste of resources, but also cause environmental pollution.

[0003] Chinese patent (CN216725851U) discloses an energy-saving circulation device for recycling and distilling NMP for lithium battery production, including a recycling circulation box, a control panel is fixedly installed on the outer surface of the recycling circulation box, and a supporting base is fixedly installed on the bottom of the recycling circulation box. A condensation recovery mechanism is set up to introduce high-concentration NMP waste gas into the recycling circulation box. At this time, condensate is added to the condenser tube, and the condensate of the condenser tube is pumped into the cooler for cooling, and the cooled condensate is pumped into the condenser tube, so that the condensate in the condenser tube is always kept in a condensed state. The gas will be cooled when passing through the condenser tube, and will float on the arc tube to condense into water droplets, and will drip into the storage tube through the guide tube for storage.

[0004] However, there are some drawbacks in the above-mentioned related technologies. For example, some NMP recovery devices for lithium battery production only use condensation components for condensation recovery, resulting in insufficient NMP recovery efficiency; even if some recovery devices use a combination of a condenser and a zeolite adsorption concentration wheel for recovery, the large temperature difference between the fluid transportation and the reaction between different devices causes energy loss and is not energy-efficient. Summary of the invention

[0005] In order to solve the above problems existing in the prior art, the present invention provides a lithium battery production waste gas treatment and recovery device, which can solve the problems raised in the above background technology.

[0006] The purpose of the present invention can be achieved through the following technical solutions:

[0007] A lithium battery production waste gas treatment and recovery device, comprising a condenser, wherein the condenser is used to condense high-concentration NMP after distillation;

[0008] A gas-liquid separation box, the top of which is fixedly connected to the condensation outlet of the condenser through a branch pipe, and a gas-liquid separation net is provided between the top wall and the bottom wall of the gas-liquid separation box;

[0009] A liquid collecting tank, wherein the top of the liquid collecting tank is provided with two liquid inlets, the bottom end of the gas-liquid separation box is fixedly connected to the adjacent liquid inlets through a branch pipe, and the bottom end of the liquid collecting tank is provided with a discharge structure;

[0010] A zeolite adsorption concentration rotor, wherein a desorption zone of the zeolite adsorption concentration rotor is provided with a gas collecting pipe;

[0011] A heat exchange box, wherein a heat exchange coil is arranged in the heat exchange box, an air inlet end of the heat exchange coil is fixedly connected to the port of the gas collecting pipe, a drainage pipe is arranged at the air outlet end of the heat exchange coil, an air inlet pipe is arranged between the heat exchange box and the gas-liquid separation box, an air outlet pipe is arranged between the heat exchange box and the air inlet area of ​​the zeolite adsorption concentration wheel, and a second solenoid valve is arranged on the side wall of the drainage pipe;

[0012] A dissolving tower, wherein a spraying structure is arranged inside the dissolving tower, and a pumping structure is arranged between the dissolving tower and the liquid collecting tank;

[0013] Preferably, the gas-liquid separation net is arranged in a tubular shape, and the top and bottom ends of the gas-liquid separation box are provided with branch pipes, and the two branch pipes of the gas-liquid separation box are arranged coaxially with the gas-liquid separation net. The NMP waste gas is first introduced into the condenser. In the condenser, the waste gas is cooled by a multi-stage cooler, and most of the NMP will be condensed into liquid. By lowering the temperature and increasing the pressure, the NMP is converted from a gaseous state to a liquid state, and a first-level NMP waste liquid and a first-level NMP gas are obtained and enter the gas-liquid separation box, and the gas-liquid separation net separates the first-level NMP waste liquid and the first-level NMP gas.

[0014] Preferably, the discharge structure comprises a discharge pipe, the discharge pipe passes through and is fixedly installed at the bottom end of the liquid collecting tank, and a first solenoid valve is provided on the side wall of the discharge pipe.

[0015] Preferably, the port of the air inlet pipe is located between the heat exchange coil and the inner wall of the gas-liquid separation box.

[0016] Preferably, an inner wall of the heat exchange box is provided with a heat-insulating layer, and the heat exchange box comprises two box bodies, and the two box bodies of the heat exchange box are buckled.

[0017] Preferably, the spray structure comprises a ring pipe, which is fixedly mounted on the inner wall of the dissolution tower through a support, a plurality of nozzles are arranged on the side wall of the ring pipe, and the ring pipe is connected to a water supply device.

[0018] Preferably, the pumping structure comprises a liquid outlet pipe, the liquid outlet pipe is connected between the dissolution tower and an adjacent liquid inlet, and a first water pump is provided on a side wall of the liquid outlet pipe.

[0019] Preferably, the water supply equipment comprises a water storage tank, a water inlet pipe is arranged between the water storage tank and the ring pipe, and a second water pump is arranged on the side wall of the water inlet pipe.

[0020] Preferably, the air inlet pipe and the air outlet pipe are made of ceramic material.

[0021] Preferably, the heat exchange coil is made of stainless steel.

[0022] The beneficial effects of the present invention are:

[0023] 1. By setting a condenser, a gas-liquid separation box, and a zeolite adsorption concentration wheel, the beneficial effect that can be obtained is that the condenser is used to condense the high-concentration NMP after distillation, the top of the gas-liquid separation box is fixedly connected to the condensation outlet of the condenser through a branch pipe, a gas-liquid separation net is arranged between the top wall and the bottom wall of the gas-liquid separation box, two liquid inlets are arranged at the top of the liquid collecting tank, the bottom end of the gas-liquid separation box is fixedly connected to the adjacent liquid inlets through a branch pipe, and a discharge structure is arranged at the bottom of the liquid collecting tank;

[0024] A zeolite adsorption concentration rotor, wherein a gas collecting pipe is arranged in a desorption zone of the zeolite adsorption concentration rotor;

[0025] The NMP waste gas is first introduced into the condenser. In the condenser, the waste gas is cooled by a multi-stage cooler, and most of the NMP will be condensed into liquid. By lowering the temperature and increasing the pressure, the NMP is changed from a gaseous state to a liquid state, and a first-level NMP waste liquid and a first-level NMP gas are obtained and enter the gas-liquid separation box. The gas-liquid separation network separates the first-level NMP waste liquid and the first-level NMP gas. The first-level NMP waste liquid enters the liquid collecting tank, and the first-level NMP gas enters the heat exchange box from the air inlet pipe, and enters the air inlet area of ​​the zeolite adsorption concentration wheel from the air outlet pipe to form a second-level NMP gas. The air pump draws the high-calorie second-level NMP gas from the air collecting pipe, the heat exchange coil and the drainage pipe into the dissolving liquid at the bottom of the dissolving tower. The dissolving liquid dissolves the second-level NMP gas to obtain a second-level NMP waste liquid. The liquid outlet pipe cooperates with the first water pump to draw the second-level NMP waste liquid into the liquid collecting tank, which has a dual waste gas recovery structure of condensation and wheel adsorption, thereby improving the recovery rate of NMP.

[0026] 2. By setting up the heat exchange box, the beneficial effect that can be obtained is that a heat exchange coil is set in the heat exchange box, the air inlet end of the heat exchange coil is fixedly connected to the port of the gas collecting pipe, the air outlet end of the heat exchange coil is set with a drainage pipe, an air inlet pipe is set between the heat exchange box and the gas-liquid separation box, an air outlet pipe is set between the heat exchange box and the air inlet area of ​​the zeolite adsorption concentration wheel, and a second solenoid valve is set on the side wall of the drainage pipe;

[0027] The primary NMP gas and the secondary NMP gas in the heat exchange box are heat exchanged through the heat exchange coil, which improves the conversion efficiency of the primary NMP gas in the zeolite adsorption concentration wheel, improves the dissolution efficiency of the secondary NMP gas in the dissolution tower, reduces energy consumption, has waste heat recovery technology, and reduces recovery energy consumption.

[0028] 3. By setting up the spray structure, the beneficial effect that can be obtained is that the spray structure includes a ring pipe, the ring pipe is fixedly installed on the inner wall of the dissolution tower through a support, a plurality of nozzles are arranged on the side wall of the ring pipe, the ring pipe is connected to a water supply device, a water inlet pipe is arranged between the water storage tank and the ring pipe, and a second water pump is arranged on the side wall of the water inlet pipe;

[0029] The air pump draws the secondary NMP gas containing high heat from the gas collecting pipe, the heat exchange coil and the drainage pipe into the dissolving liquid at the bottom of the dissolving tower. The dissolving liquid dissolves the secondary NMP gas to obtain the secondary NMP waste liquid. The liquid outlet pipe cooperates with the first water pump to draw the secondary NMP waste liquid into the liquid collecting tank. The second water pump cooperates with the water inlet pipe to draw the dissolving liquid in the water storage tank into the annular pipe. The secondary NMP gas in the dissolving tower is dissolved by spraying through multiple nozzles. The spraying dissolving structure is provided to improve the dissolving efficiency of the NMP gas. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to facilitate understanding by those skilled in the art, the present invention is further described below with reference to the accompanying drawings.

[0031] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0032] Figure 2 is a cross-sectional view of the gas-liquid separation box of the present invention;

[0033] Figure 3 It is the installation structure diagram of the gas-liquid separation box and the condenser in the present invention;

[0034] Figure 4 It is the installation structure diagram of the liquid collecting tank in the present invention;

[0035] Figure 5 This is a diagram of the installation structure of the heat exchange coil in the present invention;

[0036] Figure 6 is a cross-sectional view of the zeolite adsorption concentration rotor in the present invention;

[0037] Figure 7 It is the installation structure diagram of the dissolution tower in the present invention.

[0038] Description of reference numerals:

[0039] In the figure: 1. condenser; 2. gas-liquid separation box; 21. gas-liquid separation net; 3. liquid collecting tank; 31. liquid inlet; 32. discharge pipe; 33. first solenoid valve; 4. zeolite adsorption concentration rotor; 41. gas collecting pipe; 42. air pump; 5. heat exchange box; 51. heat exchange coil; 52. drainage pipe; 53. air inlet pipe; 54. air outlet pipe; 55. second solenoid valve; 6. dissolution tower; 61. ring pipe; 62. nozzle; 63. liquid outlet pipe; 64. first water pump; 7. water storage tank; 71. water inlet pipe; 72. second water pump. DETAILED DESCRIPTION

[0040] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the specific implementation methods, structures, features and effects of the present invention are clearly and completely described below in combination with the accompanying drawings and preferred embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] In the description of the present application, it should be understood that the orientation or position relationship indicated by "inside", "outside", etc. is based on the orientation or position described in the drawings, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, a specific orientation structure and operation, and therefore cannot be understood as a limitation on the present application.

[0042] Reference Figure 1-Figure 7 , is a lithium battery production waste gas treatment and recovery device disclosed in the present invention, comprising a condenser 1, the condenser 1 is used to condense the high-concentration NMP after distillation;

[0043] A gas-liquid separation box 2, the top of which is fixedly connected to the condensation outlet of the condenser 1 through a branch pipe, a gas-liquid separation net 21 is arranged between the top wall and the bottom wall of the gas-liquid separation box 2, the gas-liquid separation net 21 is arranged in a tubular shape, and the top and bottom ends of the gas-liquid separation box 2 are both provided with branch pipes, and the two branch pipes of the gas-liquid separation box 2 are coaxially arranged with the gas-liquid separation net 21;

[0044] The liquid collecting tank 3 has two liquid inlets 31 at the top, the bottom end of the gas-liquid separation box 2 is fixedly connected to the adjacent liquid inlets 31 through a branch pipe, and a discharge structure is provided at the bottom end of the liquid collecting tank 3. The discharge structure includes a discharge pipe 32, which passes through and is fixedly installed at the bottom end of the liquid collecting tank 3. A first solenoid valve 33 is provided on the side wall of the discharge pipe 32;

[0045] A zeolite adsorption concentration rotor 4, wherein a gas collecting pipe 41 is provided in a desorption zone of the zeolite adsorption concentration rotor 4;

[0046] A heat exchange box 5, wherein a heat exchange coil 51 is arranged in the heat exchange box 5, an air inlet end of the heat exchange coil 51 is fixedly connected to a port of the gas collecting pipe 41, a drainage pipe 52 is arranged at an air outlet end of the heat exchange coil 51, an air inlet pipe 53 is arranged between the heat exchange box 5 and the gas-liquid separation box 2, a port of the air inlet pipe 53 is located between the heat exchange coil 51 and the inner wall of the gas-liquid separation box 2, an air outlet pipe 54 is arranged between the heat exchange box 5 and the air inlet area of ​​the zeolite adsorption concentration wheel 4, and a second solenoid valve 55 is arranged on the side wall of the drainage pipe 52;

[0047] A dissolving tower 6 is provided with a spraying structure therein, the spraying structure comprises an annular tube 61, the annular tube 61 is fixedly mounted on the inner wall of the dissolving tower 6 by a support, a plurality of nozzles 62 are provided on the side wall of the annular tube 61, a pumping structure is provided between the dissolving tower 6 and the liquid collecting tank 3, the pumping structure comprises an outlet pipe 63, the outlet pipe 63 is connected between the dissolving tower 6 and the adjacent liquid inlet 31, a first water pump 64 is provided on the side wall of the outlet pipe 63, the annular tube 61 is connected with a water supply device, the water supply device comprises a water storage tank 7, a water inlet pipe 71 is provided between the water storage tank 7 and the annular tube 61, a second water pump 72 is provided on the side wall of the water inlet pipe 71.

[0048] The working principle and use process of the present invention are as follows: NMP waste gas is first introduced into the condenser 1. In the condenser 1, the waste gas is cooled by a multi-stage cooler, and most of the NMP will be condensed into liquid. By lowering the temperature and increasing the pressure, the NMP is changed from a gaseous state to a liquid state, and a first-level NMP waste liquid and a first-level NMP gas are obtained and enter the gas-liquid separation box 2. The gas-liquid separation net 21 separates the first-level NMP waste liquid and the first-level NMP gas. The first-level NMP waste liquid enters the liquid collecting tank 3. The first-level NMP gas enters the heat exchange box 5 from the air inlet pipe 53, and enters the air inlet area of ​​the zeolite adsorption concentration rotor 4 from the air outlet pipe 54. The NMP therein is effectively adsorbed by the zeolite molecular sieve, and the purified gas is directly discharged into the atmosphere. The rotor continues to rotate, and the zeolite adsorbed with NMP enters the desorption zone, and is purged with a small amount of high-temperature hot air to desorb NMP from the zeolite to form a second-level NMP gas. After the desorption, the zeolite cools down and enters the adsorption zone again to continue the adsorption process. The air pump 42 draws the high-calorie secondary NMP gas from the gas collecting pipe 41, the heat exchange coil 51 and the drainage pipe 52 into the dissolving liquid at the bottom of the dissolving tower 6. The dissolving liquid dissolves the secondary NMP gas to obtain secondary NMP waste liquid. The liquid outlet pipe 63 cooperates with the first water pump 64 to draw the secondary NMP waste liquid into the liquid collecting tank 3. The second water pump 72 cooperates with the water inlet pipe 71 to draw the dissolving liquid in the water storage tank 7 into the annular pipe 61. After spraying by multiple nozzles 62, the secondary NMP gas in the dissolving tower 6 is dissolved. At the same time, the primary NMP gas and the secondary NMP gas in the heat exchange box 5 are heat exchanged through the heat exchange coil 51, thereby improving the conversion efficiency of the primary NMP gas in the zeolite adsorption concentration wheel 4, improving the dissolution efficiency of the secondary NMP gas in the dissolving tower 6, and reducing energy consumption.

[0049] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technical personnel in this field can make some changes or modify the technical contents disclosed above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A lithium battery production waste gas treatment and recovery device, characterized in that: include: A condenser (1), wherein the condenser (1) is used to condense the high-concentration NMP after distillation; A gas-liquid separation box (2), the top end of the gas-liquid separation box (2) being fixedly connected to the condensation outlet of the condenser (1) via a branch pipe, and a gas-liquid separation net (21) being provided between the top wall and the bottom wall of the gas-liquid separation box (2); A liquid collecting tank (3), wherein the top of the liquid collecting tank (3) is provided with two liquid inlets (31), the bottom end of the gas-liquid separation box (2) is fixedly connected to adjacent liquid inlets (31) via a branch pipe, and the bottom end of the liquid collecting tank (3) is provided with a discharge structure; A zeolite adsorption concentration rotor (4), wherein a desorption zone of the zeolite adsorption concentration rotor (4) is provided with a gas collecting pipe (41); A heat exchange box (5), wherein a heat exchange coil (51) is arranged inside the heat exchange box (5), an air inlet end of the heat exchange coil (51) is fixedly connected to a port of a gas collecting pipe (41), a drainage pipe (52) is arranged at the air outlet end of the heat exchange coil (51), an air inlet pipe (53) is arranged between the heat exchange box (5) and the gas-liquid separation box (2), an air outlet pipe (54) is arranged between the heat exchange box (5) and the air inlet area of ​​the zeolite adsorption concentration rotor (4), a second solenoid valve (55) is arranged on the side wall of the drainage pipe (52), and the primary NMP gas generated by the liquid collecting tank (3) enters the air inlet area of ​​the zeolite adsorption concentration rotor (4) via the air inlet pipe (53), the heat exchange box (5) and the air outlet pipe (54) in sequence; A dissolving tower (6), wherein a spraying structure is arranged inside the dissolving tower (6), and a pumping structure is arranged between the dissolving tower (6) and the liquid collecting tank (3).

2. A lithium battery production waste gas treatment and recovery device according to claim 1, characterized in that: The gas-liquid separation net (21) is arranged in a tubular shape, and the top and bottom ends of the gas-liquid separation box (2) are both provided with branch pipes, and the two branch pipes of the gas-liquid separation box (2) are both arranged coaxially with the gas-liquid separation net (21).

3. A lithium battery production waste gas treatment and recovery device according to claim 1, characterized in that: The discharge structure comprises a discharge pipe (32), the discharge pipe (32) passing through and fixedly mounted on the bottom end of the liquid collecting tank (3), and a first solenoid valve (33) is provided on the side wall of the discharge pipe (32).

4. A lithium battery production waste gas treatment and recovery device according to claim 1, characterized in that: The port of the air inlet pipe (53) is located between the heat exchange coil (51) and the inner wall of the gas-liquid separation box (2).

5. The lithium battery production waste gas treatment and recovery device according to claim 1, characterized in that: The inner wall of the heat exchange box (5) is provided with a heat insulation layer. The heat exchange box (5) comprises two box bodies. The two box bodies of the heat exchange box (5) are arranged in a buckled manner.

6. The lithium battery production waste gas treatment and recovery device according to claim 1, characterized in that: The spray structure comprises a ring pipe (61), the ring pipe (61) being fixedly mounted on the inner wall of the dissolution tower (6) via a support, a plurality of nozzles (62) being arranged on the side wall of the ring pipe (61), and the ring pipe (61) being connected to a water supply device.

7. The lithium battery production waste gas treatment and recovery device according to claim 1, characterized in that: The pumping structure comprises a liquid outlet pipe (63), the liquid outlet pipe (63) being connected between the dissolution tower (6) and an adjacent liquid inlet (31), and a first water pump (64) being provided on a side wall of the liquid outlet pipe (63).

8. The lithium battery production waste gas treatment and recovery device according to claim 6, characterized in that: The water supply equipment comprises a water storage tank (7), a water inlet pipe (71) is provided between the water storage tank (7) and the ring pipe (61), and a second water pump (72) is provided on the side wall of the water inlet pipe (71).

9. The lithium battery production waste gas treatment and recovery device according to claim 1, characterized in that: The air inlet pipe (53) and the air outlet pipe (54) are made of ceramic material.

10. The lithium battery production waste gas treatment and recovery device according to claim 1, characterized in that: The heat exchange coil (51) is made of stainless steel.

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