Dimethyl carbonate two-stage distillation unit
By using a joint production solution of a two-stage distillation tower and an online analyzer in the dimethyl carbonate distillation device, the problem of high impurity content in industrial-grade dimethyl carbonate is solved, the battery-grade quality of the product is achieved, the service life of lithium-ion batteries is extended, and the production efficiency and economic benefits are improved.
Patent Information
- Application Number
- CN202420707278.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-08
- Publication Date
- 2025-04-08
- Estimated Expiration
- 2034-04-08
AI Technical Summary
The existing industrial-grade dimethyl carbonate contains impurities such as moisture, methanol and metal ions, and cannot meet the quality standards of lithium-ion batteries, which affects the service life of the battery and the stability of the electrolyte.
The two-stage distillation device of dimethyl carbonate is adopted. Through the joint production of the pre-stage distillation tower and the post-stage distillation tower, combined with real-time monitoring and adjustment of the online analyzer, the two-stage distillation of dimethyl carbonate is achieved, which removes impurities and improves product purity.
It improves the product quality of dimethyl carbonate, meets battery-grade standards, extends the service life of lithium-ion batteries, improves the stability of electrolyte, and improves production efficiency and economic benefits.
Smart Images
Figure CN222723632U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the field of deep processing of dimethyl carbonate, in particular to a two-stage distillation device of dimethyl carbonate. Background Art
[0002] In recent years, with the rapid development of the lithium-ion battery industry, electrolyte, as a key material in lithium-ion batteries, has higher requirements for the quality of each component. Dimethyl carbonate (DMC) is an excellent solvent with a narrow melting point and boiling point range, high surface tension, low viscosity, and small dielectric constant. It can achieve good antistatic effect, quick drying, and good compatibility with other substances. It can be widely used as an electrolyte solvent for lithium-ion batteries. In order to ensure the performance of lithium batteries, there are strict regulations on the impurity content of water, total alcohol, metal ions, etc. in dimethyl carbonate as a solvent, that is, it is required to meet the various indicators specified in the national standard GB / T 33107-2016 for batteries.
[0003] However, the current industrial-grade dimethyl carbonate still contains some impurities such as water, methanol and metal ions, which cannot reach the battery-grade level. Methanol and water affect the service life of lithium-ion batteries, and heavy component impurities affect the discoloration of the electrolyte. Therefore, in order to achieve the quality of battery-grade dimethyl carbonate, it is particularly important to improve the refining equipment during the refining process. Utility Model Content
[0004] The purpose of the utility model is to provide a two-stage distillation device for dimethyl carbonate in view of the above-mentioned defects in the prior art, which adopts double-tower joint production to improve production efficiency and greatly improve product quality. In addition, online real-time analysis is adopted to improve adjustment efficiency, so that the product reaches the quality of battery-grade dimethyl carbonate.
[0005] The utility model discloses a two-stage dimethyl carbonate distillation device, the technical scheme of which is as follows: comprising a front-stage distillation tower (1), a front-stage reboiler (2), a front-stage online analyzer (4), a first top condenser (5), a first reflux tank (6), a first reflux pump (7), a rear-stage distillation tower (9), a side condenser (11), a rear-stage online analyzer (12), a rear-stage product tank (13), a rear-stage product pump (14), a second top condenser (15), a second reflux tank (16 ), a second reflux pump (17), a main reflux pipeline (18), and a secondary reflux pipeline (19); a front-stage reboiler (2) is installed at the bottom of the front-stage distillation tower (1); crude dimethyl carbonate enters the side line inlet of the front-stage distillation tower (1) through a feed pipeline (22); the top of the front-stage distillation tower (1) is connected to a first top condenser (5) through a pipeline; the outlet of the first top condenser (5) is connected to a first reflux tank (6) through a pipeline; the lower end of the first reflux tank (6) is connected to a first reflux tank (6) through a first reflux tank (6); A pipeline and a first reflux pump (7) are connected to the upper side of the front-stage distillation tower (1); the middle side line outlet of the front-stage distillation tower (1) is connected to the middle lower side inlet of the rear-stage distillation tower (9) through a pipeline and a front-stage online analyzer (4); the middle upper side outlet of the rear-stage distillation tower (9) is connected to the side line condenser (11) through a pipeline; the outlet of the side line condenser (11) is connected to the rear-stage product tank (13) through a pipeline and a rear-stage online analyzer (12); the top of the rear-stage distillation tower (9) is connected to the rear-stage product tank (13); The second top condenser (15) is connected via a pipeline, the outlet of the second top condenser (15) is connected via a pipeline to a second reflux tank (16), the lower end of the second reflux tank (16) is connected to the side line inlet of the front-stage distillation tower (1) via a second reflux pump (17) and a main reflux pipeline (18); the lower end of the rear-stage product tank (13) is sent to the product delivery pipeline through the rear-stage product pump (14) in one way, and is connected to the main reflux pipeline (18) in the other way through the secondary reflux pipeline (19).
[0006] Preferably, a rear-stage reboiler (10) is installed at the bottom of the rear-stage distillation tower (9), and the upper-middle outlet of the rear-stage distillation tower (9) is connected to the side-line condenser (11) through a pipeline and a seventh control valve (a7), and the outlet of the side-line condenser (11) is connected to the rear-stage online analyzer (12) through a pipeline and an eighth control valve (a8).
[0007] Preferably, one outlet of the above-mentioned subsequent product pump (14) is connected to the product delivery pipeline through a pipeline and a ninth control valve (a9), and the other outlet is connected to the main return pipeline (18) through a secondary return pipeline (19), a tenth control valve (a10) and a second return flow meter (20).
[0008] Preferably, the second reflux pump (17) is connected to the main reflux pipeline (18) via a pipeline, an eleventh control valve (a11) and a third reflux flowmeter (21).
[0009] Preferably, the feed pipeline (22) is provided with a first control valve (a1), a feed flow meter (3) and a third control valve (a3).
[0010] Preferably, a second control valve (a2) is provided on the main return line (18), and the end of the main return line (18) is connected to the front side of the third control valve (a3) of the feed line (22).
[0011] Preferably, the middle side line outlet of the above-mentioned front-stage distillation tower (1) is connected to the front-stage online analyzer (4) through a pipeline and a fourth control valve (a4), and the outlet of the front-stage online analyzer (4) is connected to the side line inlet of the rear-stage distillation tower (9) through a pipeline and a sixth control valve (a6).
[0012] Preferably, the outlet of the first reflux pump (7) is connected to the upper side of the front-stage distillation tower (1) through a pipeline, a fifth control valve (a5) and a first reflux flowmeter (8).
[0013] The beneficial effects of the utility model are as follows: (1) the utility model reduces labor intensity and improves product yield by continuously feeding and outputting products, and the yield reaches more than 70%. At the same time, it reduces the load of the early reaction system and improves the processing capacity of the device; (2) the double-tower joint production is used, the front-stage distillation tower removes light components from the raw materials and the light components in the products are removed. The materials after light removal enter the rear-stage distillation tower for separation, and the heavy component materials are discharged from the bottom and the qualified products are discharged from the top. In addition, the rear-stage distillation tower stably discharges materials to the front-stage product tower for cyclic distillation, and the impurities in the quality system are effectively cut out, thereby realizing the continuous production of dimethyl carbonate; in addition, the intermediate links reduce the influence of manual operation, manual sampling and analysis and intermittent feeding and discharging, adopt online real-time analysis, improve adjustment efficiency, improve production efficiency, greatly improve product quality, increase the market competitiveness and market share of high value-added products, and increase economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Figure 1 It is a structural schematic diagram of the utility model;
[0015] In the above figure: front-stage distillation tower 1, front-stage reboiler 2, feed flowmeter 3, front-stage online analyzer 4, first top condenser 5, first reflux tank 6, first reflux pump 7, first reflux flowmeter 8, rear-stage distillation tower 9, rear-stage reboiler 10, side condenser 11, rear-stage online analyzer 12, rear-stage product tank 13, rear-stage product pump 14, second top condenser 15, second reflux tank 16, second reflux pump 17, main reflux pipeline 18, secondary reflux pipeline 19, second reflux flowmeter 20, third reflux flowmeter 21, feed pipeline 22, first control valve a1, second control valve a2, third control valve a3, fourth control valve a4, fifth control valve a5, sixth control valve a6, seventh control valve a7, eighth control valve a8, ninth control valve a9, tenth control valve a10, eleventh control valve a11. DETAILED DESCRIPTION
[0016] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.
[0017] Example 1, reference Figure 1 The utility model discloses a two-stage distillation device for dimethyl carbonate, comprising a front-stage distillation tower 1, a front-stage reboiler 2, a front-stage online analyzer 4, a first top condenser 5, a first reflux tank 6, a first reflux pump 7, a rear-stage distillation tower 9, a side condenser 11, a rear-stage online analyzer 12, a rear-stage product tank 13, a rear-stage product pump 14, a second top condenser 15, a second reflux tank 16, a second reflux pump 17, a main reflux pipeline 18, and a secondary reflux pipeline 19. The front-stage reboiler 2 is installed at the bottom of the front-stage distillation tower 1, and the crude dimethyl carbonate enters the side line inlet of the front-stage distillation tower 1 through a feed pipeline 22. The top of the front-stage distillation tower 1 is connected to the first top condenser 5 through a pipeline, and the outlet of the first top condenser 5 is connected to the first reflux tank 6 through a pipeline. The lower end of the first reflux tank 6 is connected to the first reflux tank 6 through a pipeline. A flow pump 7 is connected to the upper side of the front-stage distillation tower 1, the middle side line outlet of the front-stage distillation tower 1 is connected to the middle and lower side inlet of the rear-stage distillation tower 9 through a pipeline and a front-stage online analyzer 4, the middle and upper side outlet of the rear-stage distillation tower 9 is connected to the side line condenser 11 through a pipeline, the outlet of the side line condenser 11 is connected to the rear-stage product tank 13 through a pipeline and a rear-stage online analyzer 12, the top of the rear-stage distillation tower 9 is connected to the second top condenser 15 through a pipeline, the outlet of the second top condenser 15 is connected to the second reflux tank 16 through a pipeline, and the lower end of the second reflux tank 16 is connected to the side line inlet of the front-stage distillation tower 1 through a second reflux pump 17 and a main reflux pipeline 18; the lower end of the rear-stage product tank 13 is sent to the product delivery pipeline through the rear-stage product pump 14, and the other way is connected to the main reflux pipeline 18 through a secondary reflux pipeline 19.
[0018] Among them, a rear-stage reboiler 10 is installed at the bottom of the above-mentioned rear-stage distillation tower 9, and the upper and middle outlet of the rear-stage distillation tower 9 is connected to the side line condenser 11 through a pipeline and the seventh control valve a7, and the outlet of the side line condenser 11 is connected to the rear-stage online analyzer 12 through a pipeline and the eighth control valve a8.
[0019] The outlet of the above-mentioned rear-stage product pump 14 is connected to the product delivery pipeline through a pipeline and the ninth control valve a9, and is connected to the main reflux pipeline 18 through a secondary reflux pipeline 19, the tenth control valve a10 and the second reflux flowmeter 20.
[0020] The second reflux pump 17 is connected to the main reflux line 18 through a pipeline, an eleventh control valve a11 and a third reflux flowmeter 21 .
[0021] The feed pipeline 22 is provided with a first control valve a1, a feed flow meter 3 and a third control valve a3.
[0022] The main return line 18 is provided with a second control valve a2 , and the end of the main return line 18 is connected to the front side of the third control valve a3 of the feed line 22 .
[0023] The middle side line outlet of the above-mentioned front-stage distillation tower 1 is connected to the front-stage online analyzer 4 through a pipeline and a fourth control valve a4, and the outlet of the front-stage online analyzer 4 is connected to the side line inlet of the rear-stage distillation tower 9 through a pipeline and a sixth control valve a6.
[0024] When the utility model is used, the crude dimethyl carbonate enters the side line inlet of the front-stage distillation tower 1 through the feed pipeline 22, the front-stage distillation tower 1 performs the first-stage distillation on the crude dimethyl carbonate, removes the light components in the original crude product, and the light components are sent to the first top condenser 5 for condensation and sent to the first reflux tank 6. The condensed light components in the first reflux tank 6 are connected to the upper side of the front-stage distillation tower 1 through the first reflux pump 7 for circulation treatment; and the light-removed material in the front-stage distillation tower 1 is connected to the middle and lower side inlet of the rear-stage distillation tower 9 through the pipeline and the front-stage online analyzer 4, and the rear-stage distillation tower 9 The light component material is discharged from the top of the tower, and then returned to the front-stage distillation tower 1 through the main reflux line 18 for further distillation. The qualified product is discharged from the tower of the rear-stage distillation tower 9, and then connected to the rear-stage product tank 13 through the side line condenser 11 and the rear-stage online analyzer 12, so as to realize the continuous production of battery-grade products; of course, if the requirements of battery-grade products are not met after the analysis of the rear-stage online analyzer 12, the ninth control valve a9 can be closed, and the tenth control valve a10 can be opened, and the product can be sent to the main reflux line 18 through the secondary reflux line 19 and returned to the front-stage distillation tower 1 for further distillation until the requirements of battery-grade products are met. The continuous feeding and discharging of materials to produce products reduces labor intensity, improves product yield, and the yield reaches more than 70%, which increases the output of battery-grade products of the device; product quality is improved, the market competitiveness and market share of high value-added products are increased, and economic benefits are greatly increased.
[0025] Example 2, reference Figure 1The utility model discloses a two-stage distillation device for dimethyl carbonate, comprising a front-stage distillation tower 1, a front-stage reboiler 2, a front-stage online analyzer 4, a first top condenser 5, a first reflux tank 6, a first reflux pump 7, a rear-stage distillation tower 9, a side condenser 11, a rear-stage online analyzer 12, a rear-stage product tank 13, a rear-stage product pump 14, a second top condenser 15, a second reflux tank 16, a second reflux pump 17, a main reflux pipeline 18, and a secondary reflux pipeline 19. The front-stage reboiler 2 is installed at the bottom of the front-stage distillation tower 1, and the crude dimethyl carbonate enters the side line inlet of the front-stage distillation tower 1 through a feed pipeline 22. The top of the front-stage distillation tower 1 is connected to the first top condenser 5 through a pipeline, and the outlet of the first top condenser 5 is connected to the first reflux tank 6 through a pipeline. The lower end of the first reflux tank 6 is connected to the first reflux tank 6 through a pipeline. A flow pump 7 is connected to the upper side of the front-stage distillation tower 1, the middle side line outlet of the front-stage distillation tower 1 is connected to the middle and lower side inlet of the rear-stage distillation tower 9 through a pipeline and a front-stage online analyzer 4, the middle and upper side outlet of the rear-stage distillation tower 9 is connected to the side line condenser 11 through a pipeline, the outlet of the side line condenser 11 is connected to the rear-stage product tank 13 through a pipeline and a rear-stage online analyzer 12, the top of the rear-stage distillation tower 9 is connected to the second top condenser 15 through a pipeline, the outlet of the second top condenser 15 is connected to the second reflux tank 16 through a pipeline, and the lower end of the second reflux tank 16 is connected to the side line inlet of the front-stage distillation tower 1 through a second reflux pump 17 and a main reflux pipeline 18; the lower end of the rear-stage product tank 13 is sent to the product delivery pipeline through the rear-stage product pump 14, and the other way is connected to the main reflux pipeline 18 through a secondary reflux pipeline 19.
[0026] The difference from Example 1 is:
[0027] The outlet of the first reflux pump 7 is connected to the upper side of the front-stage distillation tower 1 through a pipeline, a fifth control valve a5 and a first reflux flowmeter 8, so that the light components refluxed to the front-stage distillation tower 1 can be controlled and monitored online.
[0028] The above is only a preferred embodiment of the utility model. Any person skilled in the art may modify the utility model by using the above technical solution or modify it into an equivalent technical solution. Therefore, any simple modification or equivalent transformation based on the technical solution of the utility model shall fall within the scope of protection claimed by the utility model.
Claims
1. A two-stage distillation device for dimethyl carbonate, characterized in that: The invention comprises a front-stage distillation tower (1), a front-stage reboiler (2), a front-stage online analyzer (4), a first top condenser (5), a first reflux tank (6), a first reflux pump (7), a rear-stage distillation tower (9), a side condenser (11), a rear-stage online analyzer (12), a rear-stage product tank (13), a rear-stage product pump (14), a second top condenser (15), a second reflux tank (16), a second reflux pump (17), a main reflux pipeline (18), and a secondary reflux pipeline (19). The front-stage reboiler (2) is installed at the bottom of the front-stage distillation tower (1), the crude dimethyl carbonate enters the side inlet of the front-stage distillation tower (1) through a feed pipeline (22), the top of the front-stage distillation tower (1) is connected to the first top condenser (5) through a pipeline, the outlet of the first top condenser (5) is connected to the first reflux tank (6) through a pipeline, and the lower end of the first reflux tank (6) is connected to the first reflux pump (7) through a pipeline. The upper side of the front-stage distillation tower (1), the middle side line outlet of the front-stage distillation tower (1) is connected to the middle lower side inlet of the rear-stage distillation tower (9) through a pipeline and a front-stage online analyzer (4), the middle upper side outlet of the rear-stage distillation tower (9) is connected to the side line condenser (11) through a pipeline, the outlet of the side line condenser (11) is connected to the rear-stage product tank (13) through a pipeline and a rear-stage online analyzer (12), and the top of the rear-stage distillation tower (9) is connected to the second A top condenser (15), the outlet of the second top condenser (15) is connected to a second reflux tank (16) through a pipeline, the lower end of the second reflux tank (16) is connected to the side line inlet of the front-stage distillation tower (1) through a second reflux pump (17) and a main reflux pipeline (18); the lower end of the rear-stage product tank (13) is sent to the product delivery pipeline through the rear-stage product pump (14) in one way, and is connected to the main reflux pipeline (18) in the other way through the secondary reflux pipeline (19).
2. The dimethyl carbonate two-stage distillation device according to claim 1, characterized in that: A rear-stage reboiler (10) is installed at the bottom of the rear-stage distillation tower (9); the upper-middle outlet of the rear-stage distillation tower (9) is connected to a side-line condenser (11) via a pipeline and a seventh control valve (a7); and the outlet of the side-line condenser (11) is connected to a rear-stage online analyzer (12) via a pipeline and an eighth control valve (a8).
3. The dimethyl carbonate two-stage distillation device according to claim 2, characterized in that: One outlet of the post-stage product pump (14) is connected to the product delivery pipeline through a pipeline and a ninth control valve (a9), and the other outlet is connected to the main return pipeline (18) through a secondary return pipeline (19), a tenth control valve (a10) and a second return flow meter (20).
4. The dimethyl carbonate two-stage distillation device according to claim 3, characterized in that: The second reflux pump (17) is connected to the main reflux pipeline (18) through a pipeline, an eleventh control valve (a11) and a third reflux flow meter (21).
5. The dimethyl carbonate two-stage distillation device according to claim 1, characterized in that: The feed pipeline (22) is provided with a first control valve (a1), a feed flow meter (3), and a third control valve (a3).
6. The dimethyl carbonate two-stage distillation device according to claim 5, characterized in that: The main return line (18) is provided with a second control valve (a2), and the end of the main return line (18) is connected to the front side of the third control valve (a3) of the feed line (22).
7. The dimethyl carbonate two-stage distillation device according to claim 6, characterized in that: The middle side line outlet of the front-stage distillation tower (1) is connected to the front-stage online analyzer (4) through a pipeline and a fourth control valve (a4), and the outlet of the front-stage online analyzer (4) is connected to the side line inlet of the rear-stage distillation tower (9) through a pipeline and a sixth control valve (a6).
8. The dimethyl carbonate two-stage distillation device according to claim 7, characterized in that: The outlet of the first reflux pump (7) is connected to the upper side of the front-stage distillation tower (1) through a pipeline, a fifth control valve (a5) and a first reflux flowmeter (8).