NMP waste liquid recovery device

Abstract

The utility model relates to an NMP waste liquid recovery device which comprises a tower body, a demisting plate, a packing layer and a liquid storage cavity are sequentially arranged in the tower body from top to bottom, a rotating shaft is further vertically arranged in the center of the tower body, a spraying assembly and a stirring assembly are further arranged on the upper half section and the lower half section of the rotating shaft, and an exhaust pipe is arranged on one side of the top of the tower body. A liquid discharge pipe and a gas inlet pipe are arranged at the bottom of the tower body, the liquid discharge pipe is horizontally arranged and is communicated with the liquid storage cavity, and the gas inlet pipe is vertically arranged and is communicated with the stirring assembly; the original fixed input gas hole is changed into a rotatable input structure, and a stirring structure is synchronously added above the gas hole, so that the contact range with water is expanded, and the intersolubility between waste gas and water is effectively enhanced; in addition, a filler layer is additionally arranged at the top of the tower, a large number of water films are formed in the filler layer so as to capture NMP gas in waste gas, the NMP gas finally converges in the liquid storage cavity at the bottom along the tower wall, and the use effect of waste gas recovery is further improved.

Description

Technical Field

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

[0002] N-Methylpyrrolidone (NMP for short) is a colorless transparent liquid with a boiling point of 204°C and a flash point of 95°C. It has low viscosity, a slight ammonia smell, good chemical and thermal stability, high polarity, low volatility, and is miscible with water in any ratio. This material is commonly used in lithium battery production.

[0003] 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.

[0004] The commonly used recovery tower has a relatively simple structure. The gas is only introduced directly into the water at the bottom of the tower at a fixed position so as to be mixed with the water. The gas floats out quickly, which limits the contact with the water. In addition, the gas transmission position is fixed, and the water around the pore will be saturated first, thus affecting the subsequent miscibility effect. Utility Model Content

[0005] Based on the above description, the utility model provides an NMP waste liquid recovery device to solve the shortcomings of the existing recovery equipment, which has a single structure and simply passes the gas into water for mutual dissolution, has a short contact time and poor mutual dissolution effect, and the gas transmission position is fixed, so that the water around the pores reaches a saturated state first, thereby affecting the subsequent mutual dissolution effect.

[0006] The utility model is realized by the following technical solutions:

[0007] A NMP waste liquid recovery device comprises a tower body, wherein a demister plate, a packing layer and a liquid storage cavity are sequentially arranged inside the tower body from top to bottom, a rotating shaft is vertically arranged at the center of the tower body, the rotating shaft sequentially penetrates the demister plate, the packing layer and the liquid storage cavity from top to bottom and makes both ends penetrate to the outside of the tower body respectively, a spray assembly and a stirring assembly are further arranged on the upper half and the lower half of the rotating shaft, wherein the spray assembly is arranged above the packing layer, and the stirring assembly is arranged at the bottom of the liquid storage cavity, an exhaust pipe is arranged on one side of the top of the tower body, and a drain pipe and an air inlet pipe are arranged at the bottom of the tower body, wherein the drain pipe is horizontally arranged and communicated with the liquid storage cavity, and the air inlet pipe is vertically arranged and communicated with the stirring assembly.

[0008] On the basis of the above technical solution, the present invention can also be improved as follows.

[0009] Furthermore, the demister plate and the packing layer are arranged in a circular ring shape and are provided with a ball bearing at the center. The rotating shaft is movably plugged into the center of the ball bearing and is provided with sealing gaskets on both sides.

[0010] Furthermore, a first cavity and a second cavity are provided inside the rotating shaft and are not connected to each other, wherein the first cavity and the second cavity extend toward both ends of the rotating shaft respectively and form circular openings, and the spray assembly and the air inlet pipe are connected to the two openings respectively.

[0011] Furthermore, the spray assembly includes a spray pipe and a water pipe, wherein a plurality of the spray pipes are provided, each of the spray pipes is integrally formed with the rotating shaft and its interior is interconnected with the first cavity, the water pipe is arranged above the tower body and its bottom port is connected with the opening at the top of the rotating shaft, and the other end of the water pipe is externally connected to a water pump.

[0012] Furthermore, the plurality of spray pipes are arranged in a circular array with the rotating shaft as the center, and a plurality of nozzles are arranged on the bottom surface of each spray pipe, and the bottom end of the nozzle is close to the surface of the packing layer.

[0013] Furthermore, the stirring assembly includes an air pipe and a stirring frame, wherein the air pipes are arranged in a plurality and are arranged in a circular array around the periphery of the rotating shaft, and each of the air pipes is connected to the interior of the second cavity, and a plurality of air holes are provided on the side wall of the air pipe facing upward, and the stirring frame is arranged above the air pipe and has four stirring frames, which are arranged in a cross shape and fixedly connected to the side wall of the rotating shaft.

[0014] Furthermore, the stirring frame is a rectangular frame and is filled with a large number of spoiler balls at the center, and metal meshes are respectively provided on both sides of the stirring frame and are fixedly connected to the side walls of the stirring frame.

[0015] Furthermore, the internal filler of the packing layer is a ball ring or a Raschig ring.

[0016] Furthermore, a driving motor is also provided at the bottom of the tower body, and matching bevel gears are provided on the output end of the driving motor and the outer side wall of the bottom end of the rotating shaft and mesh with each other.

[0017] Compared with the prior art, the technical solution of this application has the following beneficial technical effects:

[0018] 1. This application is based on the improvement of the existing waste liquid recovery equipment. The original fixed input air hole is changed to a rotatable input structure, and a stirring structure is added on top of it, which can not only drive water disturbance, thereby expanding the contact range with the waste gas, but also cut the waste gas bubbles in the floating process during the stirring process, making them into smaller bubbles, thereby further expanding the contact range with water, and effectively enhancing the mutual solubility between the waste gas and water;

[0019] 2. The present application also arranges an additional packing layer on the top, and forms a large amount of water film inside the packing layer by spraying, so as to capture the NMP gas in the exhaust gas, and finally collects it in the liquid storage chamber at the bottom along the tower wall, thereby further improving the use effect of exhaust gas recovery. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a structural schematic diagram of the tower body in this embodiment;

[0021] Figure 2 Schematic diagram of the internal structure of the tower body in this embodiment;

[0022] Figure 3 Schematic diagram of the internal structure of the rotating shaft in this embodiment;

[0023] Wherein: 1. tower body; 11. exhaust pipe; 12. drain pipe; 13. air inlet pipe; 2. packing layer; 3. defog plate; 4. rotating shaft; 41. first cavity; 42. second cavity; 5. spray assembly; 51. spray pipe; 52. water pipe; 53. nozzle; 6. stirring assembly; 61. air pipe; 62. stirring frame; 7. driving motor. DETAILED DESCRIPTION

[0024] In order to facilitate understanding of the present application, the present application will be described more fully below with reference to the relevant drawings. Embodiments of the present application are provided in the drawings. However, the present 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 the present application more thorough and comprehensive.

[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0026] Combination Figure 1-3 As shown, a NMP waste liquid recovery device comprises:

[0027] The tower body 1 is a cylindrical structure, mainly used to provide auxiliary support for other components;

[0028] The demister plate 3 is arranged at the top of the tower body 1 to separate water mist from the air;

[0029] The packing layer 2 is arranged inside the tower body 1 and below the demister plate 3, and is used to produce a water film through the packing, thereby increasing the mixing effect with the NMP gas in the exhaust gas;

[0030] The liquid storage chamber is located at the bottom of the tower body 1 and is mainly used to store water and a mixed liquid mixed with NMP waste liquid for centralized recycling;

[0031] The rotating shaft 4 is vertically arranged inside the tower body 1 and can rotate freely, with both ends extending to the outside of the tower body 1;

[0032] The spray assembly 5 is arranged above the packing layer 2 to cooperate with the packing layer 2 to form a water film;

[0033] A stirring assembly 6 is arranged in the liquid storage chamber to stir the bottom liquid to increase the mixing efficiency;

[0034] The driving motor 7 is arranged at the bottom of the tower and is drivingly connected to the bottom end of the rotating shaft 4, and is the power source for rotation.

[0035] Specifically, the tower body 1 is hollow inside, and the demister plate 3, the packing layer 2 and the liquid storage chamber are arranged in sequence from top to bottom. At the same time, the demister plate 3 and the packing layer 2 are both annular structures, and a ball bearing is provided at the center. The rotating shaft 4 is vertically inserted into the center hole of the ball bearing so that it can rotate flexibly. At the same time, sealing gaskets should be used on both sides of the ball bearing for sealing.

[0036] An exhaust pipe 11 is provided at the top of the tower body 1, and the air separated by the defogger plate 3 can be discharged from the exhaust pipe 11; a drain pipe 12 and an air inlet pipe 13 are provided at the bottom of the tower body 1, wherein the drain pipe 12 is horizontally arranged and connected with the liquid storage cavity, and the connection point is as close as possible to the bottom surface of the liquid storage cavity so as to discharge the recovered liquid inside the liquid storage cavity, and the air inlet pipe 13 is vertically arranged at the bottom center of the tower body 1.

[0037] Based on the above structure, in this embodiment, the interior of the rotating shaft 4 is set to be hollow, and there are a first cavity 41 and a second cavity 42 at the same time, which are independent of each other and not connected to each other, and the first cavity 41 and the second cavity 42 extend toward the upper and lower ends of the rotating shaft 4 respectively and form circular openings at the top and bottom thereof respectively, wherein the air inlet pipe 13 is connected to the circular opening at the bottom, and the opening at the top is connected to the spray assembly 5.

[0038] In this structure, the circular opening should also be arranged with a bearing structure similar to that at the center of the demister plate 3 and the packing layer 2, so that the normal gas and water delivery work will not be affected during the rotation of the shaft 4.

[0039] The spray assembly 5 includes a water pipe 52 and a spray pipe 51, wherein at least four spray pipes 51 are arranged in a circular array and are integrally provided with the rotating shaft 4 so that the interior of the spray pipe 51 is connected with the first cavity 41, and the water pipe 52 is arranged above the tower body 1, and its bottom end is vertically inserted into the opening at the top of the rotating shaft 4, and the other end is connected with the water pump. At the same time, a plurality of nozzles 53 are provided on the downward side of the spray pipe 51. The nozzles 53 utilize the rotation function of the rotating shaft 4 to effectively cover the entire top surface of the packing layer 2, thereby forming a large amount of water film inside it to capture the NMP gas in the exhaust gas.

[0040] The stirring assembly 6 includes an air pipe 61 and a stirring frame 62. The air pipe 61 is provided with multiple ones, which are arranged in a circular array, and each one is integrally arranged with the rotating shaft 4, and its interior is connected to the second cavity 42. At the same time, a number of air holes are provided on its top surface. The concentrated and collected exhaust gas is discharged into the air pipe 61 through the air inlet pipe 13 and the second cavity 42, and then discharged into the water in the form of bubbles. The stirring frame 62 is arranged above the air pipe 61, and its structure is rectangular, and metal meshes are provided on both sides. A spoiler ball is filled in the middle of the metal mesh. The spoiler ball structure is similar to the ABS flocculation ball structure. In the actual stirring process, the spoiler ball structure can perform secondary disturbance on the water flow through the incision to form a large number of micro vortices. At the same time, it can also quickly cut larger bubbles to break them up into a large number of small bubbles, thereby effectively increasing the contact range between the exhaust gas and water, thereby improving the mutual dissolution effect.

[0041] The internal structure of the packing layer 2 uses ball rings or Raschig rings as packing.

[0042] The driving motor 7 is horizontally arranged on the bottom surface of the tower bottom, and a bevel gear with the same size and structure as the bottom end of the rotating shaft 4 is provided on its output end, and the two are meshed with each other to form a transmission structure.

[0043] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model, rather than to limit it. Although the utility model has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solution recorded in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solution from the technical solution of the embodiments of the utility model.

Claims

1. A NMP waste liquid recovery device, characterized in that, The invention comprises a tower body (1), wherein a demister plate (3), a packing layer (2) and a liquid storage chamber are sequentially arranged inside the tower body (1) from top to bottom, and a rotating shaft (4) is vertically arranged at the center of the tower body (1), wherein the rotating shaft (4) passes through the demister plate (3), the packing layer (2) and the liquid storage chamber in sequence from top to bottom and allows both ends to pass through the outside of the tower body (1), respectively; a spray assembly (5) and a stirring assembly (6) are also arranged on the upper and lower halves of the rotating shaft (4), wherein the spray assembly (5) is arranged above the packing layer (2), and the stirring assembly (6) is arranged at the bottom of the liquid storage chamber; an exhaust pipe (11) is arranged on one side of the top of the tower body (1), and a liquid discharge pipe (12) and an air intake pipe (13) are arranged at the bottom of the tower body (1), wherein the liquid discharge pipe (12) is horizontally arranged and communicated with the liquid storage chamber, and the air intake pipe (13) is vertically arranged and communicated with the stirring assembly (6).

2. According to a NMP waste liquid recovery device described in claim 1, it is characterized in that, The demisting plate (3) and the packing layer (2) are arranged in a circular ring shape and are provided with a ball bearing at the center. The rotating shaft (4) is movably plugged into the center of the ball bearing and is provided with sealing gaskets on both sides.

3. According to a NMP waste liquid recovery device described in claim 1, it is characterized in that, A first cavity (41) and a second cavity (42) are provided inside the rotating shaft (4) and are not connected to each other, wherein the first cavity (41) and the second cavity (42) extend toward both ends of the rotating shaft (4) and are formed with circular openings, respectively, and the spray assembly (5) and the air inlet pipe (13) are connected to the two openings respectively.

4. According to a NMP waste liquid recovery device described in claim 3, it is characterized in that, The spray assembly (5) comprises a spray pipe (51) and a water pipe (52), wherein a plurality of the spray pipes (51) are provided, each of the spray pipes (51) is integrally formed with the rotating shaft (4) and its interior is communicated with the first cavity (41), the water pipe (52) is arranged above the tower body (1) and its bottom port is communicated with an opening at the top of the rotating shaft (4), and the other end of the water pipe (52) is externally connected to a water pump.

5. According to a NMP waste liquid recovery device described in claim 4, it is characterized in that, The plurality of spray pipes (51) are arranged in a circular array with the rotating shaft (4) as the center, and a plurality of nozzles (53) are arranged on the bottom surface of each spray pipe (51), and the bottom end of the nozzle (53) is close to the surface of the packing layer (2).

6. A NMP waste liquid recovery device according to claim 3, characterized in that, The stirring assembly (6) comprises an air delivery pipe (61) and a stirring frame (62), wherein the air delivery pipes (61) are arranged in a plurality and arranged in a circular array around the periphery of the rotating shaft (4), and each of the air delivery pipes (61) is communicated with the interior of the second cavity (42), and a plurality of air delivery holes are provided on the side wall of the air delivery pipe (61) facing upwards. Four stirring frames (62) are arranged above the air delivery pipe (61), and the four stirring frames (62) are arranged in a cross shape and fixedly connected to the side wall of the rotating shaft (4).

7. A NMP waste liquid recovery device according to claim 6, characterized in that, The stirring frame (62) is a rectangular frame and is filled with a large number of spoiler balls at the center. Metal meshes are also provided on both sides of the stirring frame (62) and are fixedly connected to the side walls of the stirring frame (62).

8. According to a NMP waste liquid recovery device described in claim 1, it is characterized in that, The internal filler of the packing layer (2) is a ball ring or a Raschig ring.

9. A NMP waste liquid recovery device according to claim 1, characterized in that, A driving motor (7) is also provided at the bottom of the tower body (1), and matching bevel gears are provided on the output end of the driving motor (7) and the outer wall of the bottom end of the rotating shaft (4) and mesh with each other.

Images