CN117924084A - System and method for removing ethyl acetate in vinyl acetate production process - Google Patents
System and method for removing ethyl acetate in vinyl acetate production process Download PDFInfo
- Publication number
- CN117924084A CN117924084A CN202211312477.4A CN202211312477A CN117924084A CN 117924084 A CN117924084 A CN 117924084A CN 202211312477 A CN202211312477 A CN 202211312477A CN 117924084 A CN117924084 A CN 117924084A
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- China
- Prior art keywords
- ethyl acetate
- tower
- rectifying tower
- vinyl acetate
- distillation tank
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- XEKOWRVHYACXOJ-UHFFFAOYSA-N Ethyl acetate Chemical compound CCOC(C)=O XEKOWRVHYACXOJ-UHFFFAOYSA-N 0.000 title claims abstract description 345
- XTXRWKRVRITETP-UHFFFAOYSA-N Vinyl acetate Chemical compound CC(=O)OC=C XTXRWKRVRITETP-UHFFFAOYSA-N 0.000 title claims abstract description 58
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 26
- 238000000034 method Methods 0.000 title claims abstract description 18
- 238000004821 distillation Methods 0.000 claims abstract description 49
- 229940093499 ethyl acetate Drugs 0.000 claims description 117
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 claims description 33
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 20
- 239000012295 chemical reaction liquid Substances 0.000 claims description 8
- 238000010992 reflux Methods 0.000 claims description 8
- 239000003112 inhibitor Substances 0.000 claims description 6
- 238000006116 polymerization reaction Methods 0.000 claims description 6
- 239000000463 material Substances 0.000 claims description 5
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical group O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 4
- 238000007599 discharging Methods 0.000 description 4
- VGGSQFUCUMXWEO-UHFFFAOYSA-N Ethene Chemical compound C=C VGGSQFUCUMXWEO-UHFFFAOYSA-N 0.000 description 2
- 239000005977 Ethylene Substances 0.000 description 2
- 239000001569 carbon dioxide Substances 0.000 description 2
- 229910002092 carbon dioxide Inorganic materials 0.000 description 2
- 239000004372 Polyvinyl alcohol Substances 0.000 description 1
- 239000000853 adhesive Substances 0.000 description 1
- 230000001070 adhesive effect Effects 0.000 description 1
- HSFWRNGVRCDJHI-UHFFFAOYSA-N alpha-acetylene Natural products C#C HSFWRNGVRCDJHI-UHFFFAOYSA-N 0.000 description 1
- 239000013064 chemical raw material Substances 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 125000002534 ethynyl group Chemical group [H]C#C* 0.000 description 1
- 239000003973 paint Substances 0.000 description 1
- 229920002451 polyvinyl alcohol Polymers 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 239000004753 textile Substances 0.000 description 1
- 229920006163 vinyl copolymer Polymers 0.000 description 1
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/10—Process efficiency
Landscapes
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention discloses a system and a method for removing ethyl acetate in the production process of vinyl acetate, wherein the system comprises a rectifying tower, a de-ethyl acetate tower distillation tank and a rectifying tower distillation tank; the side line of the rectifying tower is connected with the ethyl acetate removing tower, the tower bottom of the ethyl acetate removing tower is connected with the tower kettle of the rectifying tower through a pipeline, the tower top of the ethyl acetate removing tower is sequentially connected with the ethyl acetate removing tower condenser and the ethyl acetate removing tower distillation tank through pipelines, and the ethyl acetate side outlet of the ethyl acetate removing tower distillation tank is connected with the top of the ethyl acetate removing tower through a pipeline; the top of the rectifying tower is sequentially connected with a rectifying tower condenser, a condensate cooler and a rectifying tower distillation tank through pipelines, and a crude vinyl acetate side outlet of the rectifying tower distillation tank is connected with the top of the rectifying tower through a pipeline. By adopting the system and the method for removing the ethyl acetate in the vinyl acetate production process, the ethyl acetate content in the produced vinyl acetate is less than or equal to 250mg/kg, which is superior to the specification of industrial vinyl acetate superior products.
Description
Technical Field
The invention relates to the technical field of vinyl acetate preparation, in particular to a system and a method for removing ethyl acetate in a vinyl acetate production process.
Background
Vinyl acetate is an important chemical raw material and is widely used for manufacturing polyvinyl alcohol, vinyl copolymer resin, adhesive, paint, textile processing, paper coating and the like. The production process route of vinyl acetate mainly comprises an ethylene method and an acetylene method, wherein the ethylene method is more and more important due to the advantages of low energy consumption, environmental friendliness and the like.
Most of vinyl acetate produced by the prior art is in industrial vinyl acetate qualified product specification, the ethyl acetate content in the product is not required, but the vinyl acetate product also contains a small amount of ethyl acetate which is difficult to remove, and a system and a method for effectively removing the ethyl acetate are absent in the vinyl acetate production process at present.
Disclosure of Invention
The invention aims at overcoming the defects in the prior art and provides a system and a method for removing ethyl acetate in the production process of vinyl acetate.
In order to achieve the above purpose, the present invention adopts the following technical scheme:
The first aspect of the invention provides a system for removing ethyl acetate in the production process of vinyl acetate, which comprises a rectifying tower, an ethyl acetate removing tower distillation tank and a rectifying tower distillation tank; the side line of the rectifying tower is connected with the ethyl acetate removal tower, the bottom of the ethyl acetate removal tower is connected with the tower kettle of the rectifying tower through a pipeline, the top of the ethyl acetate removal tower is sequentially connected with an ethyl acetate removal tower condenser and an ethyl acetate removal tower distillation tank through pipelines, and the ethyl acetate side outlet of the ethyl acetate removal tower distillation tank is connected with the top of the ethyl acetate removal tower through a pipeline; the top of the rectifying tower is sequentially connected with a rectifying tower condenser, a condensate cooler and a rectifying tower distillation tank through pipelines, and a crude vinyl acetate side outlet of the rectifying tower distillation tank is connected with the top of the rectifying tower through pipelines.
Further, an ethyl acetate discharging pipeline is also branched on the connecting pipeline of the ethyl acetate removing tower distillation tank and the ethyl acetate removing tower; and a water side outlet of the ethyl acetate removal tower distillation tank is connected with a first water discharge pipeline.
Further, a connecting pipeline of the distillation tank of the rectifying tower and the rectifying tower is also branched with a crude vinyl acetate discharging pipeline; and a water side outlet of the distillation tank of the rectifying tower is connected with a second water discharge pipeline.
Further, the rectifying tower is also connected with a reaction liquid feeding pipeline and a polymerization inhibitor feeding pipeline.
Further, the rectifying tower has 20-50 theoretical plates, the operating pressure is 0.0-0.15 MPaG, the operating temperature is 50-150 ℃, and the reflux ratio is 3.0-6.
Further, the ethyl acetate removing tower has 20-40 theoretical plates, the operating pressure is 0.0-0.15 MPaG, the operating temperature is 50-150 ℃, and the reflux ratio is 5-20.
The second aspect of the invention provides a method for removing ethyl acetate in the production process of vinyl acetate, which adopts the system and comprises the following steps:
The reaction liquid and the polymerization inhibitor are sent into a rectifying tower, acetic acid is discharged from the tower bottom of the rectifying tower, a material obtained from the side line of the rectifying tower is sent into a de-ethylacetate tower, the gas phase at the tower top of the de-ethylacetate tower is condensed by a condenser of the de-ethylacetate tower and then enters a distillation tank of the de-ethylacetate tower, and part of ethyl acetate discharged from an ethyl acetate side outlet of the distillation tank of the de-ethylacetate tower is sent back to the de-ethylacetate tower; the gas phase at the top of the rectifying tower is condensed by a rectifying tower condenser and a condensate cooler, cooled and then enters a rectifying tower distillation tank, and a part of crude vinyl acetate extracted from a crude vinyl acetate side outlet of the rectifying tower distillation tank is sent back to the rectifying tower.
Further, the reaction liquid as the feed of the rectifying tower contains 40-70% of acetic acid by mass, 10-28% of vinyl acetate by mass, 4-10% of water by mass and 100-1000 ppm of ethyl acetate by mass.
Further, the ethyl acetate removing tower comprises 60-80% of acetic acid by mass, 3-20% of vinyl acetate by mass, 0.5-3% of ethyl acetate by mass and 6-15% of water by mass.
Further, the feed to the de-ethylacetate column is taken from theoretical plates 3-10 (from bottom to top) of the rectification column.
Compared with the prior art, the invention has the following advantages:
by adopting the system and the method for removing the ethyl acetate in the vinyl acetate production process, the ethyl acetate content in the produced vinyl acetate is less than or equal to 250mg/kg, which is superior to the specification of industrial vinyl acetate superior products.
Drawings
Figure 1 is a schematic diagram of a system for removing ethyl acetate in a vinyl acetate production process according to the present invention,
Wherein the reference numerals are as follows:
1-a rectifying tower; 2-ethyl acetate removal tower; 3-distilling off the ethyl acetate removing tower; a 4-ethyl acetate removal tower condenser; 5-a rectifying tower condenser; 6-a condensate cooler; 7-a distillation tank of the rectifying tower.
Detailed Description
The present invention will be described in detail and specifically by way of the following specific examples and drawings to provide a better understanding of the present invention, but the following examples do not limit the scope of the present invention.
Referring to fig. 1, the invention provides a system for removing ethyl acetate in the production process of vinyl acetate, which comprises a rectifying tower 1, an ethyl acetate removing tower 2, an ethyl acetate removing tower distillation tank 3 and a rectifying tower distillation tank 7; the side line of the rectifying tower 1 is connected with the ethyl acetate removing tower 2, the tower bottom of the ethyl acetate removing tower 2 is connected with the tower kettle of the rectifying tower 1 through a pipeline, the tower top of the ethyl acetate removing tower 2 is sequentially connected with the ethyl acetate removing tower condenser 4 and the ethyl acetate removing tower distillation tank 3 through pipelines, and the ethyl acetate side outlet of the ethyl acetate removing tower distillation tank 3 is connected with the top of the ethyl acetate removing tower 2 through a pipeline; the top of the rectifying tower 1 is sequentially connected with a rectifying tower condenser 5, a condensate cooler 6 and a rectifying tower distillation tank 7 through pipelines, and a crude vinyl acetate side outlet of the rectifying tower distillation tank 7 is connected with the top of the rectifying tower 1 through a pipeline.
In the invention, an ethyl acetate discharging pipeline is also branched on the connecting pipeline of the ethyl acetate removing tower distillation tank 3 and the ethyl acetate removing tower 2; the water side outlet of the ethyl acetate removal tower distillation tank 3 is connected with a first water discharge pipeline.
In the invention, a connecting pipeline of the distillation tank 7 of the rectifying tower and the rectifying tower 1 is also branched with a crude vinyl acetate discharging pipeline; the water side outlet of the rectifying tower distillation tank 7 is connected with a second water discharge pipeline.
In the invention, the rectifying tower 1 is also connected with a reaction liquid feeding pipeline and a polymerization inhibitor feeding pipeline.
As a preferable example, the rectifying tower 1 has 20 to 50 theoretical plates, the operating pressure is 0.0 to 0.15MPaG, the operating temperature is 50 to 150 ℃, and the reflux ratio is 3.0 to 6.
As a preferred example, the ethyl acetate removing tower 2 has 20-40 theoretical plates, the operating pressure is 0.0-0.15 MPaG, the operating temperature is 50-150 ℃, and the reflux ratio is 5-20.
The invention also provides a method for removing ethyl acetate in the production process of vinyl acetate, which adopts the system and comprises the following steps:
The reaction solution and the polymerization inhibitor are sent into a rectifying tower 1, acetic acid is discharged from the tower kettle of the rectifying tower 1, a stream of material is extracted from the side line of the rectifying tower 1 and is sent into a de-ethylacetate tower 2, the gas phase at the top of the de-ethylacetate tower 2 is condensed by a de-ethylacetate tower condenser 4 and then enters a de-ethylacetate tower distillation tank 3, and part of ethyl acetate extracted from the ethyl acetate side outlet of the de-ethylacetate tower distillation tank 3 is sent back into the de-ethylacetate tower 2; the gas phase at the top of the rectifying tower 1 is condensed by a rectifying tower condenser 5 and a condensate cooler 6, enters a rectifying tower distillation tank 7 after being cooled, and part of the crude vinyl acetate extracted from the crude vinyl acetate side outlet of the rectifying tower distillation tank 7 is sent back to the rectifying tower 1.
As a preferable example, the reaction liquid fed into the rectifying tower 1 contains 40 to 70% by mass of acetic acid, 10 to 28% by mass of vinyl acetate, 4 to 10% by mass of water and 100 to 1000ppm by mass of ethyl acetate.
As a preferable example, the ethyl acetate removing tower 2 is fed with 60-80% of acetic acid, 3-20% of vinyl acetate, 0.5-3% of ethyl acetate and 6-15% of water.
As a preferred example, the feed to the de-ethylacetate column 2 is taken from theoretical plates 3-10 (from bottom to top) of the rectification column 1.
Example 1
Vinyl Acetate (VAC) production scale is 10 ten thousand tons/year. The rectifying tower has 32 theoretical plates, the operating pressure is 0.0-0.06 MPaG, the operating temperature is 70-130 ℃, the reflux ratio is 4.3, the acetic acid content is 69.2%, the vinyl acetate content is 22.5%, the water content is 7.8%, the ethyl acetate content is 350ppm, and the rest is carbon dioxide in the composition of the rectifying tower feed. The total of 28 theoretical plates are arranged in the ethyl acetate removing tower, the operating pressure is 0.0-0.04 MPaG, the operating temperature is 70-127 ℃, and the feeding material of the ethyl acetate removing tower is extracted from the 6 th theoretical plate (from bottom to top) of the rectifying tower. The ethyl acetate content in the side-extracted ethyl acetate removing tower is 1.1 percent, and the ethyl acetate content at the top of the rectifying tower is 200ppm.
Example 2
Vinyl Acetate (VAC) production scale is 30 ten thousand tons/year. The rectifying tower has 35 theoretical plates, the operating pressure is 0.0-0.05 MPaG, the operating temperature is 70-128 ℃, the reflux ratio is 5, the acetic acid content in the composition of the feeding of the rectifying tower is 65%, the vinyl acetate content is 27.2%, the water content is 7.4%, the ethyl acetate content is 300ppm, and the rest is carbon dioxide. The total of 30 theoretical plates are arranged in the ethyl acetate removing tower, the operating pressure is 0.0-0.035 MPaG, the operating temperature is 70-126 ℃, and the feeding material of the ethyl acetate removing tower is extracted from the 6 th theoretical plate (from bottom to top) of the rectifying tower. The ethyl acetate content in the side-extracted ethyl acetate removing tower is 1.05%, and the ethyl acetate content at the top of the rectifying tower is 150ppm.
The foregoing description is only illustrative of the preferred embodiments of the present invention and is not intended to limit the embodiments and scope of the present invention, and it should be appreciated by those skilled in the art that equivalent substitutions and obvious variations may be made using the teachings of the present invention and the accompanying drawings, all of which are included in the scope of the present invention.
Claims (10)
1. The system for removing the ethyl acetate in the production process of the vinyl acetate is characterized by comprising a rectifying tower (1), an ethyl acetate removing tower (2), an ethyl acetate removing tower distillation tank (3) and a rectifying tower distillation tank (7); the side line of the rectifying tower (1) is connected with the ethyl acetate removal tower (2), the bottom of the ethyl acetate removal tower (2) is connected with the tower kettle of the rectifying tower (1) through a pipeline, the top of the ethyl acetate removal tower (2) is sequentially connected with an ethyl acetate removal tower condenser (4) and an ethyl acetate removal tower distillation tank (3) through a pipeline, and an ethyl acetate side outlet of the ethyl acetate removal tower distillation tank (3) is connected with the top of the ethyl acetate removal tower (2) through a pipeline; the top of the rectifying tower (1) is sequentially connected with a rectifying tower condenser (5), a condensate cooler (6) and a rectifying tower distillation tank (7) through pipelines, and a crude vinyl acetate side outlet of the rectifying tower distillation tank (7) is connected with the top of the rectifying tower (1) through pipelines.
2. The system for removing ethyl acetate in the vinyl acetate production process according to claim 1, wherein the connecting pipeline of the ethyl acetate removal tower distillation tank (3) and the ethyl acetate removal tower (2) is further branched with an ethyl acetate discharge pipeline; the water side outlet of the ethyl acetate removal tower distillation tank (3) is connected with a first water discharge pipeline.
3. The system for removing ethyl acetate in the vinyl acetate production process according to claim 1, wherein a crude vinyl acetate discharge pipeline is further branched on a connecting pipeline of the distillation tank (7) of the rectifying tower and the rectifying tower (1); the water side outlet of the rectifying tower distillation groove (7) is connected with a second water discharge pipeline.
4. The system for removing ethyl acetate in the process of producing vinyl acetate according to claim 1, wherein the rectifying tower (1) is further connected with a reaction liquid feeding line and a polymerization inhibitor feeding line.
5. The system for removing ethyl acetate in a vinyl acetate production process according to claim 1, wherein the rectifying tower (1) has 20-50 theoretical plates in total, the operating pressure is 0.0-0.15 MPaG, the operating temperature is 50-150 ℃, and the reflux ratio is 3.0-6.
6. The system for removing ethyl acetate in a vinyl acetate production process according to claim 1, wherein the ethyl acetate removing tower (2) has 20-40 theoretical plates in total, the operating pressure is 0.0-0.15 mpa g, the operating temperature is 50-150 ℃, and the reflux ratio is 5-20.
7. A method for removing ethyl acetate in a vinyl acetate production process, using the system as claimed in any one of claims 1 to 6, comprising the steps of:
The reaction liquid and the polymerization inhibitor are sent into a rectifying tower (1), acetic acid is discharged from a tower kettle of the rectifying tower (1), a lateral line of the rectifying tower (1) is used for collecting a stream of materials and is sent into a de-ethylacetate tower (2), a tower top gas phase of the de-ethylacetate tower (2) is condensed by a de-ethylacetate tower condenser (4) and then enters a de-ethylacetate tower distillation tank (3), and part of ethyl acetate collected from an ethyl acetate side outlet of the de-ethylacetate tower distillation tank (3) is sent back to the de-ethylacetate tower (2); the gas phase at the top of the rectifying tower (1) is condensed and cooled by a rectifying tower condenser (5) and a condensate cooler (6) and then enters a rectifying tower distillation tank (7), and a part of crude vinyl acetate extracted from a crude vinyl acetate side outlet of the rectifying tower distillation tank (7) is returned to the rectifying tower (1).
8. The method for removing ethyl acetate in a vinyl acetate production process according to claim 7, wherein the reaction liquid fed as a rectifying column (1) has a mass content of acetic acid of 40 to 70%, a mass content of vinyl acetate of 10 to 28%, a mass content of water of 4 to 10% and a mass content of ethyl acetate of 100 to 1000ppm.
9. The method for removing ethyl acetate in the production process of vinyl acetate according to claim 7, wherein the ethyl acetate removing tower (2) is fed with 60-80% by mass of acetic acid, 3-20% by mass of vinyl acetate, 0.5-3% by mass of ethyl acetate and 6-15% by mass of water.
10. The method for removing ethyl acetate in a vinyl acetate production process according to claim 7 where the feed to the de-ethylacetate column (2) is taken from the 3 rd to 10 th theoretical plates of the rectification column (1).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211312477.4A CN117924084A (en) | 2022-10-25 | 2022-10-25 | System and method for removing ethyl acetate in vinyl acetate production process |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211312477.4A CN117924084A (en) | 2022-10-25 | 2022-10-25 | System and method for removing ethyl acetate in vinyl acetate production process |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117924084A true CN117924084A (en) | 2024-04-26 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202211312477.4A Pending CN117924084A (en) | 2022-10-25 | 2022-10-25 | System and method for removing ethyl acetate in vinyl acetate production process |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117924084A (en) |
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2022
- 2022-10-25 CN CN202211312477.4A patent/CN117924084A/en active Pending
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