NMP waste gas treatment device

Abstract

The utility model relates to an NMP (N-Methyl Pyrrolidone) waste gas treatment device which comprises a recovery tower, a demister, a filler layer and a storage cavity are arranged in the recovery tower, a spraying assembly is mounted on the top surface of the filler layer, a rotating shaft is arranged at the center of the spraying assembly, and a driving motor is further arranged at the top of the recovery tower and is in transmission connection with the rotating shaft; an air inlet pipe and a water outlet pipe are further arranged on the side wall of the recovery tower, an atomization assembly is arranged on the air inlet pipe, and an exhaust pipe is further arranged at the top of the recovery tower; an existing recovery tower is improved, traditional gas-liquid mixing is replaced with the mode that atomized water and waste gas are conveyed in a mixed mode, in the structure, the diffusion range of the atomized water is large, compared with traditional gas-liquid mixing, the atomized water can be mixed into the waste gas for synchronous conveying, and the waste gas recycling efficiency is improved. Therefore, the NMP in the waste gas can be in contact for a long time, the absorption effect of the NMP is further improved, negative pressure conveying can be achieved, no extra power source needs to be arranged, and the refitting cost is greatly reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of waste gas recovery equipment, in particular to an NMP waste gas treatment device. Background Art

[0002] In the production process of lithium batteries, as the positive and negative electrode materials and diaphragms of lithium batteries are produced, the NMP solution used will continue to evaporate. These volatile solutions will lead to the waste of NMP raw materials and are also prone to cause certain environmental pollution. Therefore, they need to be recycled.

[0003] The commonly used recovery method is to inject the gas directly into water to make the water molecules and NMP gas in the air miscible, thereby preliminarily filtering the air, and then purifying it again through the packing layer and other structures before discharging it. The whole structure is relatively simple, especially in the existing tower structure, which is mostly introduced into the water inside the bottom of the tower at a fixed position. The gas delivery speed is relatively fast, and the gas will move upward quickly in the water with a short residence time, which leads to limited contact with water, and the water around the exhaust hole will be saturated first, thus affecting the subsequent miscibility effect. Utility Model Content

[0004] Based on the above description, the utility model provides an NMP waste gas treatment device to solve the shortcomings of the existing NMP recovery structure being relatively simple, the actual contact between water and waste gas being relatively short, and the exhaust position being fixed, which is very easy to be affected by the surrounding water saturation and the subsequent miscibility effect with NMP.

[0005] The utility model is realized through the following technical solutions:

[0006] An NMP waste gas treatment device comprises a recovery tower, wherein a demister, a packing layer and a storage chamber are sequentially arranged inside the recovery tower from top to bottom, wherein an annular mounting groove is provided at the edge of the top surface of the packing layer, a spray assembly is rotatably mounted on the mounting groove, a rotating shaft is provided at the center of the spray assembly and extends upward to the top surface of the recovery tower, and a driving motor is also provided on the top of the recovery tower and is transmission-connected to the rotating shaft; an air inlet pipe and a water outlet pipe are also provided on the side wall of the recovery tower, wherein an atomizing assembly is provided on the air inlet pipe, and the atomizing assembly and the spray assembly are both connected to the same water pump through a water pipe, and an exhaust pipe is also provided on the top of the recovery tower.

[0007] On the basis of the above technical solution, the present invention can also be improved as follows.

[0008] Furthermore, through holes of the same size are provided at the center of the demister and the center of the top surface of the recovery tower, a bearing seat is provided inside the through hole, the rotating shaft is vertically inserted into the bearing seat and sealing gaskets are provided on both sides.

[0009] Further, the spraying assembly includes a mounting frame arranged in a ring shape. A cross-shaped support is provided at the center of the mounting frame. Both the cross-shaped support and the interior of the mounting frame are hollow and interconnected. A plurality of columnar protruding parts are also arranged in a ring on the top surface of the mounting frame. A plurality of spray nozzles are provided on the side of the protruding part facing the recovery tower.

[0010] Further, a plurality of the spray nozzles are all arranged to incline downward, and the inclination angles of the plurality of spray nozzles increase sequentially from top to bottom.

[0011] Further, the inside of the rotating shaft is hollow. An inlet hole is also provided at the center of the cross-shaped support. The inlet hole is locked and fixed to the bottom end of the rotating shaft through a flange.

[0012] Further, a ball bearing seat is installed on the inner wall at the top end of the rotating shaft. The water delivery pipe is vertically inserted into the center of the ball bearing. A plurality of tooth blocks are also arranged in a ring on the outer side wall of the rotating shaft. The driving motor is arranged horizontally and is provided with a tooth sleeve at the output end. The tooth sleeve meshes with the tooth blocks.

[0013] Further, the atomization assembly includes an atomization box arranged at one side of the recovery tower at intervals. A spray pipe with a mesh structure is arranged in the atomization box. A plurality of atomizers are detachably installed on the bottom surface of the spray pipe. A branch pipe is provided on the side wall of the air inlet pipe and communicates upward with the inside of the atomization box.

[0014] Compared with the prior art, the technical solution of the present application has the following beneficial technical effects:

[0015] 1. The present application is improved based on the existing recovery tower. The method of mixing and transporting atomized water with waste gas is adopted to replace the traditional gas-liquid mixing. In this structure, the diffusion range of the atomized water is large, which can ensure complete coverage of every position in the waste gas, thereby improving its absorption effect on NMP. At the same time, compared with the traditional gas-liquid mixing, the atomized water in the present application can be mixed into the waste gas for synchronous transportation. Therefore, it can be in contact with NMP in the waste gas for a longer time, further improving its absorption effect. Moreover, in the present application, by using the principle of aerodynamics, a negative pressure transportation of the atomized water can be formed, eliminating the need to additionally arrange a power source, greatly reducing the modification cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic structural diagram of the recovery tower and the atomization assembly in this embodiment;

[0017] Figure 2 It is a schematic structural diagram of the spraying assembly in this embodiment;

[0018] Figure 3 It is a schematic structural diagram of the spraying range of the spray nozzles in this embodiment;

[0019] Figure 4 It is a schematic diagram of the internal structure of the atomization tank in this embodiment;

[0020] Wherein: 1. Recovery tower; 11. Rotating shaft; 12. Water delivery pipe; 2. Demister; 3. Packing layer; 4. Spraying assembly; 41. Mounting frame; 42. Cross-shaped support; 43. Nozzle; 5. Atomization assembly; 51. Atomization tank; 52. Spraying pipe; 53. Atomizer; 6. Driving motor. Specific embodiments

[0021] To facilitate the understanding of this application, the following will describe this application more comprehensively with reference to the relevant attached drawings. Embodiments of this application are shown in the drawings. However, this application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of this application more thorough and comprehensive.

[0022] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which this application belongs. The terms used in the specification of this application herein are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0023] Combined with Figures 1-4 As shown, an NMP waste gas treatment device includes:

[0024] Recovery tower 1, which is the main body of the recovery tower 1, is arranged in a cylindrical shape, with an exhaust pipe provided on its top surface, and an intake pipe and a drain pipe provided on the side wall of the lower half;

[0025] Demister 2, which is a cyclone plate type demisting structure, contacts with water mist through spiral blades, thereby separating gas and water to achieve the effect of filtration and separation;

[0026] Packing layer 3, which is arranged inside the recovery tower 1 and below the demister 2, is filled with a large number of Pall rings or Raschig rings inside, and a large number of water films are formed through the packing to capture NMP gas in the waste gas, so as to achieve the purpose of gas purification;

[0027] Receiving cavity, which is the hollow cavity of the lower half of the recovery tower 1, and is used to temporarily store the recovered NMP solution;

[0028] Spraying assembly 4, which is arranged on the top surface of the packing layer 3 and is used to spray water on the packing to form a water film;

[0029] Atomization assembly 5, which is arranged on one side of the recovery tower 1 and is communicated with the intake pipe, and through the way of atomizing and spraying water, it is preliminarily mixed with the waste gas to expand the mutual solubility range of water and NMP gas and improve the recovery rate.

[0030] Specifically, through holes of the same size are provided at the center of the demister 2 and the top surface center of the recovery tower 1. A bearing seat is provided inside the through hole, and a rotating shaft 11 is vertically arranged inside. The top end of the rotating shaft 11 extends upward outside the tower body, and the bottom end extends downward and is close to the spraying assembly 4.

[0031] The spraying assembly 4 is composed of a mounting frame 41, a cross-shaped bracket 42, and a number of nozzles 43. The mounting frame 41 is arranged in a ring shape, and a mounting groove is arranged around the top surface edge of the packing layer 3. The bottom part of the mounting frame 41 protrudes downward and is movably inserted into the mounting groove. The cross-shaped bracket 42 is arranged at the center of the mounting frame 41, and both the mounting frame 41 and the cross-shaped bracket 42 are arranged in a hollow structure and communicate with each other. At least 6 cylindrical protrusions are also provided on the top surface of the mounting frame 41. The inside of the protrusion is hollow and a hole is provided on the side facing the center of the tower body. The nozzle 43 is fixedly installed inside the hole and is arranged to incline downward.

[0032] In the above structure, it is necessary to ensure that the nozzles 43 can completely cover all the packing and achieve the effect of spraying water. Therefore, a water inlet hole should be provided at the center of the top surface of the cross-shaped bracket 42. At the same time, the rotating shaft 11 should also be arranged in a hollow structure, and a flange should be provided at both the water inlet hole and the bottom end of the rotating shaft 11 and locked and fixed by bolts, so that the rotating shaft 11 can supply water inside and drive the entire spraying assembly 4 to rotate.

[0033] In addition, a ball bearing should be provided on the inner wall of the top end of the rotating shaft 11. A water delivery pipe 12 is inserted into the center of the ball bearing, and both sides of the ball bearing are sealed with gaskets. When the water delivery pipe 12 is filled with water, the rotating shaft 11 can still rotate freely without interference.

[0034] The rotating shaft 11 should also be provided with a corresponding power source. Tooth blocks should be provided on its outer side wall. At the same time, a driving motor 6 is horizontally arranged on the top surface of the recovery tower 1. A tooth sleeve is provided at the output end of the driving motor 6, and the tooth sleeve meshes with the tooth blocks to drive the rotating shaft 11 to rotate inside the tower body.

[0035] In the above structure, the inclination angles of the nozzles 43 gradually increase from top to bottom. The purpose is to completely cover the packing in the packing layer 3, and reference can be made to Figure 3 the shown spraying principle.

[0036] The atomization box 51 is arranged in a rectangle, and branch pipes are provided on the bottom surface. The branch pipes extend downward and are connected to the air inlet pipe. The atomization box 51 is also connected to the outside through a ventilation port, and a filter is provided on the ventilation port to prevent impurities and dust from the outside from affecting the purification effect inside the tower body.

[0037] When the waste gas in the intake pipe is discharged into the tower body at a relatively high speed, a negative pressure will be formed inside the atomization box 51, thereby extracting the water mist inside the atomization box 51, making it mix quickly with the waste gas and discharging them into the tower body together.

[0038] During this process, the water mist and the waste gas will be fully mixed, thus greatly increasing the contact range between the water mist and the NMP gas, enabling them to dissolve quickly with each other, and then being captured at the packing layer 3. The purified gas will continue to move upward, pass through the demister 2 for secondary filtration, and then be discharged outside the tower body.

[0039] Inside the atomization box 51, there is a spray pipe 52 with a mesh structure. Multiple atomizers 53 are arranged on the top surface of the spray pipe 52 facing downward to quickly produce water mist for comprehensive coverage of the waste gas. At the same time, one end of the spray pipe 52 extends outward and forms a water inlet on the surface of the atomization box 51. This water inlet is also connected to a water delivery pipe 12. Therefore, in this embodiment, both the spray assembly 4 and the atomization assembly 5 are supplied with water by the same water pump.

[0040] In addition, in order to facilitate the staff to control the input ratio of the atomized water and the waste gas, a flow meter should be set on the intake pipe and the branch pipe respectively.

[0041] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the technical solutions of the embodiments of the present invention.

Claims

1. A NMP waste gas treatment device, characterized in that: The invention comprises a recovery tower (1), wherein a demister (2), a packing layer (3) and a storage chamber are arranged in sequence from top to bottom inside the recovery tower (1), wherein an annular mounting groove is provided at the edge of the top surface of the packing layer (3), a spray assembly (4) is rotatably mounted on the mounting groove, a rotating shaft (11) is provided at the center of the spray assembly (4) and extends upward to the top surface of the recovery tower (1), and a driving motor (6) is also provided at the top of the recovery tower (1) and is transmission-connected to the rotating shaft (11); an air inlet pipe and a water outlet pipe are also provided on the side wall of the recovery tower (1), wherein an atomizing assembly (5) is provided on the air inlet pipe, and the atomizing assembly (5) and the spray assembly (4) are both connected to the same water pump through a water delivery pipe (12), and an exhaust pipe is also provided at the top of the recovery tower (1).

2. According to the NMP waste gas treatment device described in claim 1, it is characterized in that: Through holes of the same size are provided at the center of the demister (2) and the center of the top surface of the recovery tower (1), a bearing seat is provided inside the through hole, the rotating shaft (11) is vertically inserted into the inside of the bearing seat and sealing gaskets are provided on both sides.

3. According to the NMP waste gas treatment device described in claim 1, it is characterized in that: The spray assembly (4) comprises a mounting frame (41) arranged in a ring shape, a cross-shaped bracket (42) being provided at the center of the mounting frame (41), and the interiors of the cross-shaped bracket (42) and the mounting frame (41) are both hollow and interconnected, and a plurality of columnar protrusions are also arranged around the top surface of the mounting frame (41), and a plurality of spray heads are provided on a side of the protrusion facing the recovery tower (1).

4. According to the NMP waste gas treatment device described in claim 3, it is characterized in that: The plurality of nozzles (43) are all arranged tilted downward, and the tilt angles of the plurality of nozzles (43) increase sequentially from top to bottom.

5. According to the NMP waste gas treatment device described in claim 4, it is characterized in that: The interior of the rotating shaft (11) is hollow, and a water inlet hole is also provided at the center of the cross-shaped bracket (42). The water inlet hole is locked and fixed to the bottom end of the rotating shaft (11) via a flange.

6. According to the NMP waste gas treatment device described in claim 5, it is characterized in that: A ball bearing seat is installed on the inner wall of the top end of the rotating shaft (11), the water pipe (12) is vertically plugged into the center of the ball bearing, and a gear block is arranged around the outer wall of the rotating shaft (11). The driving motor (6) is arranged horizontally and has a gear sleeve on the output end, and the gear sleeve and the gear block are meshed with each other.

7. The NMP waste gas treatment device according to claim 1, characterized in that: The atomizing assembly (5) comprises an atomizing box (51) arranged at intervals on one side of the recovery tower (1), a spray pipe (52) with a mesh structure is provided in the atomizing box (51), a plurality of atomizers (53) are detachably mounted on the bottom surface of the spray pipe (52), and a branch pipe is provided on the side wall of the air inlet pipe and is upwardly connected to the interior of the atomizing box (51).

Images