Recovery system for dimethyl carbonate tail gas in lithium battery electrolyte production process

Abstract

The utility model relates to the technical field of dimethyl carbonate tail gas recovery, in particular to a system for recovering dimethyl carbonate tail gas in a lithium battery electrolyte production process, which is characterized in that the DMC tail gas enters a first inlet end at the bottom of a first adsorption tank through a connecting pipeline; the first outlet end of the top of the first adsorption tank is connected with the first inlet end of the top of the second adsorption tank through a pipeline, and the first outlet end of the bottom of the second adsorption tank is connected with the inlet end of the chimney through a pipeline; nitrogen enters the second inlet end of the first adsorption tank through a connecting pipeline, the second outlet end of the first adsorption tank is connected with the second inlet end of the second adsorption tank through a pipeline, the second outlet end of the second adsorption tank is connected with the inlet end of the analysis tank through a pipeline, and the outlet end of the analysis tank is connected with the inlet end of the condenser through a pipeline. The outlet end of the condenser is connected with the inlet end of the gas-liquid separator through a pipeline, and the first outlet end of the gas-liquid separator is connected with the inlet end of the solvent tank through a pipeline; and the recovery efficiency of the DMC tail gas is effectively improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of dimethyl carbonate tail gas recovery, in particular to a dimethyl carbonate tail gas recovery system in the production process of lithium battery electrolyte. Background Art

[0002] Dimethyl carbonate is a non-toxic, environmentally friendly and widely used chemical raw material. It is an important organic synthesis intermediate. Its molecular structure contains functional groups such as hydroxyl, methyl and methoxy. It has multiple reaction properties. It is safe, convenient, less polluting and easy to transport in production. Due to its low toxicity, dimethyl carbonate is a green chemical product with development prospects.

[0003] Today, green and low-carbon development has become a global trend. Especially in the production process of lithium battery electrolyte, the recovery of dimethyl carbonate tail gas is particularly important. Utility Model Content

[0004] The utility model aims to overcome the shortcomings of the prior art and provide a dimethyl carbonate tail gas recovery system in the production process of lithium battery electrolyte which has a simple structure, is easy to operate and can improve the recovery efficiency and adsorption quality.

[0005] The utility model solves the technical problem by adopting the following technical solutions:

[0006] A system for recovering dimethyl carbonate tail gas in a lithium battery electrolyte production process, comprising:

[0007] A first adsorption tank, a second adsorption tank, a chimney, a desorption tank, a condenser, a gas-liquid separator and a solvent tank, the DMC tail gas enters the first inlet end of the bottom of the first adsorption tank through a connecting pipe, the first outlet end of the top of the first adsorption tank is connected to the first inlet end of the top of the second adsorption tank through a pipe, and the first outlet end of the bottom of the second adsorption tank is connected to the inlet end of the chimney through a pipe;

[0008] The nitrogen enters the second inlet end of the first adsorption tank through a connecting pipe, the second outlet end of the first adsorption tank is connected to the second inlet end of the second adsorption tank through a pipe, the second outlet end of the second adsorption tank is connected to the inlet end of the decomposition tank through a pipe, the outlet end of the decomposition tank is connected to the inlet end of the condenser through a pipe, the outlet end of the condenser is connected to the inlet end of the gas-liquid separator through a pipe, and the first outlet end of the gas-liquid separator is connected to the inlet end of the solvent tank through a pipe.

[0009] Moreover, a flame arrester and an exhaust gas fan are also provided on the connecting pipe between the DMC exhaust gas and the first adsorption tank. The DMC exhaust gas enters the inlet end of the flame arrester through the connecting pipe, the outlet end of the flame arrester is connected to the inlet end of the exhaust gas fan through a pipe, and the outlet end of the exhaust gas fan is connected to the first inlet end of the bottom of the first adsorption tank through a pipe.

[0010] Moreover, a vacuum pressure pump is arranged on the connecting pipe between the outlet end of the analysis tank and the inlet end of the condenser. The outlet end of the analysis tank is connected to the inlet end of the vacuum pressure pump through a pipe, and the outlet end of the vacuum pressure pump is connected to the inlet end of the condenser through a pipe.

[0011] Moreover, the second outlet end of the gas-liquid separator is connected to the inlet end of the exhaust fan through a pipeline.

[0012] Moreover, it also includes a solvent pump, the first outlet end of the solvent tank is connected to the inlet end of the solvent pump through a pipeline, and the outlet end of the solvent pump is connected to the outside.

[0013] Moreover, the second outlet end of the solvent tank is connected to the inlet end of the exhaust fan through a pipeline.

[0014] Moreover, activated carbon layers are arranged in the first adsorption tank, the second adsorption tank and the analysis tank.

[0015] The advantages and positive effects of the utility model are:

[0016] The utility model allows DMC tail gas to enter the activated carbon bed in the adsorption tank through the tail gas blower, DMC is adsorbed by the activated carbon, and the purified gas is directly discharged. The main device adopts three adsorption tanks to work, two of which complete the two-stage adsorption, and the other one is switched at a fixed time. During desorption, the vacuum pressure pump is turned on to reduce the pressure in the adsorption tank, and the DMC adsorbed on the activated carbon is desorbed. In the later stage of desorption, a small amount of nitrogen is sent in through the purge valve to purge the activated carbon bed, so as to desorb DMC to a greater extent, and at the same time complete the regeneration of the activated carbon bed, thereby further improving the recovery efficiency of dimethyl carbonate. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of the utility model.

[0018] Reference numerals

[0019] 1-chimney, 2-flame arrester, 3-exhaust fan, 4-first adsorption tank, 5-second adsorption tank, 6-analysis tank, 7-condenser, 8-vacuum pressure pump, 9-gas-liquid separator, 10-solvent tank, 11-solvent pump. DETAILED DESCRIPTION

[0020] The present invention will be further described in detail below with reference to the accompanying drawings and through specific embodiments. The following embodiments are merely descriptive and not restrictive, and the protection scope of the present invention cannot be limited thereto. Example

[0021] like Figure 1 As shown, a system for recovering dimethyl carbonate tail gas in a lithium battery electrolyte production process comprises:

[0022] A first adsorption tank 4, a second adsorption tank 5, a chimney 1, a desorption tank 6, a condenser 7, a gas-liquid separator 9 and a solvent tank 10, the DMC tail gas enters the first inlet end of the bottom of the first adsorption tank 4 through a connecting pipe, the first outlet end of the top of the first adsorption tank 4 is connected to the first inlet end of the top of the second adsorption tank 5 through a pipe, and the first outlet end of the bottom of the second adsorption tank 5 is connected to the inlet end of the chimney 1 through a pipe;

[0023] The nitrogen enters the second inlet end of the first adsorption tank 4 through the connecting pipe, the second outlet end of the first adsorption tank 4 is connected to the second inlet end of the second adsorption tank 5 through a pipe, the second outlet end of the second adsorption tank 5 is connected to the inlet end of the decomposition tank 6 through a pipe, the outlet end of the decomposition tank 6 is connected to the inlet end of the condenser 7 through a pipe, the outlet end of the condenser 7 is connected to the inlet end of the gas-liquid separator 9 through a pipe, and the first outlet end of the gas-liquid separator 9 is connected to the inlet end of the solvent tank 10 through a pipe.

[0024] The first adsorption tank 4, the second adsorption tank 5 and the analysis tank 6 are all provided with an activated carbon layer, and the tank body is cylindrical, φ1000×1200. The activated carbon layer has a certain attraction to the dimethyl carbonate waste gas. When the dimethyl carbonate passes through the activated carbon layer, the organic matter therein is retained, so that the waste gas is purified. During analysis, the pressure of the activated carbon layer is reduced to separate the organic matter in the activated carbon.

[0025] In order to perform fire-retardant pretreatment, a flame arrester 2 and an exhaust fan 3 are also provided on the connecting pipe between the DMC exhaust gas and the first adsorption tank 4. The DMC exhaust gas enters the inlet end of the flame arrester 2 through the connecting pipe, and the outlet end of the flame arrester 2 is connected to the inlet end of the exhaust fan 3 through a pipe, and the outlet end of the exhaust fan 3 is connected to the first inlet end of the bottom of the first adsorption tank 4 through a pipe.

[0026] A vacuum pressure pump 8 is also arranged on the connecting pipe between the outlet end of the analysis tank 6 and the inlet end of the condenser 7. The outlet end of the analysis tank 6 is connected to the inlet end of the vacuum pressure pump 8 through a pipe, and the outlet end of the vacuum pressure pump 8 is connected to the inlet end of the condenser 7 through a pipe.

[0027] The second outlet end of the gas-liquid separator 9 is connected to the inlet end of the exhaust fan 3 through a pipeline.

[0028] A solvent pump 11 is also included. The first outlet end of the solvent tank 10 is connected to the inlet end of the solvent pump 11 through a pipeline, and the outlet end of the solvent pump 11 is connected to the outside.

[0029] In order to send the volatilized gas back into the adsorption system for secondary adsorption, the second outlet end of the solvent tank 10 is connected to the inlet end of the exhaust blower 3 through a pipeline. Example

[0030] A system for recovering dimethyl carbonate tail gas in a lithium battery electrolyte production process is the same as that of Example 1 except that the positions of a desorption tank 6 and an adsorption tank are different.

[0031] Working principle:

[0032] First, the DMC tail gas is pretreated through the flame arrester 2, and then the tail gas fan 3 is turned on. The DMC tail gas enters from the bottom of the first adsorption tank 4, and is sent from the top of the first adsorption tank 4 to the second adsorption tank 5, and is subjected to secondary adsorption in the second adsorption tank 5. After the adsorption is completed, it is sent from the bottom of the second adsorption tank 5 to the chimney 1; after the adsorption is completed, the nitrogen is sent to the first adsorption tank 4 and the second adsorption tank 5, and after coming out of the analysis tank 6, it is sent to the condenser 7 through the vacuum pressure pump 8, and then sent to the gas-liquid separator 9 for gas-liquid separation, and the non-condensable gas is sent back to the adsorption system through the pipeline for re-adsorption, and the liquid DMC enters the solvent tank 10, and the sewage at the bottom of the solvent tank 10 flows out.

[0033] Although the embodiments and drawings of the present invention are disclosed for illustrative purposes, those skilled in the art will appreciate that various substitutions, changes and modifications are possible without departing from the spirit and scope of the present invention and the appended claims. Therefore, the scope of the present invention is not limited to the contents disclosed in the embodiments and drawings.

Claims

1. A system for recovering dimethyl carbonate tail gas in the production process of lithium battery electrolyte, characterized in that: A first adsorption tank, a second adsorption tank, a chimney, a desorption tank, a condenser, a gas-liquid separator and a solvent tank, the DMC tail gas enters the first inlet end of the bottom of the first adsorption tank through a connecting pipe, the first outlet end of the top of the first adsorption tank is connected to the first inlet end of the top of the second adsorption tank through a pipe, and the first outlet end of the bottom of the second adsorption tank is connected to the inlet end of the chimney through a pipe; The nitrogen enters the second inlet end of the first adsorption tank through a connecting pipe, the second outlet end of the first adsorption tank is connected to the second inlet end of the second adsorption tank through a pipe, the second outlet end of the second adsorption tank is connected to the inlet end of the decomposition tank through a pipe, the outlet end of the decomposition tank is connected to the inlet end of the condenser through a pipe, the outlet end of the condenser is connected to the inlet end of the gas-liquid separator through a pipe, and the first outlet end of the gas-liquid separator is connected to the inlet end of the solvent tank through a pipe.

2. The system for recovering dimethyl carbonate tail gas in the production process of lithium battery electrolyte according to claim 1, characterized in that: A flame arrester and an exhaust gas fan are also provided on the connecting pipe between the DMC exhaust gas and the first adsorption tank. The DMC exhaust gas enters the inlet end of the flame arrester through the connecting pipe, the outlet end of the flame arrester is connected to the inlet end of the exhaust gas fan through a pipe, and the outlet end of the exhaust gas fan is connected to the first inlet end of the bottom of the first adsorption tank through a pipe.

3. The system for recovering dimethyl carbonate tail gas in the production process of lithium battery electrolyte according to claim 1, characterized in that: A vacuum pressure pump is also arranged on the connecting pipe between the outlet end of the analysis tank and the inlet end of the condenser. The outlet end of the analysis tank is connected to the inlet end of the vacuum pressure pump through a pipe, and the outlet end of the vacuum pressure pump is connected to the inlet end of the condenser through a pipe.

4. The system for recovering dimethyl carbonate tail gas in the production process of lithium battery electrolyte according to claim 1, characterized in that: The second outlet end of the gas-liquid separator is connected to the inlet end of the tail gas fan through a pipeline.

5. The system for recovering dimethyl carbonate tail gas in the production process of lithium battery electrolyte according to claim 1, characterized in that: It also includes a solvent pump. The first outlet end of the solvent tank is connected to the inlet end of the solvent pump through a pipeline, and the outlet end of the solvent pump is connected to the outside.

6. The system for recovering dimethyl carbonate tail gas in the production process of lithium battery electrolyte according to claim 1, characterized in that: The second outlet end of the solvent tank is connected to the inlet end of the exhaust fan through a pipeline.

7. The system for recovering dimethyl carbonate tail gas in the production process of lithium battery electrolyte according to claim 1, characterized in that: The first adsorption tank, the second adsorption tank and the analysis tank are all provided with activated carbon layers.

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