CN108358874B - Multi-section production method and device for diketene - Google Patents
Multi-section production method and device for diketene Download PDFInfo
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- CN108358874B CN108358874B CN201810038346.9A CN201810038346A CN108358874B CN 108358874 B CN108358874 B CN 108358874B CN 201810038346 A CN201810038346 A CN 201810038346A CN 108358874 B CN108358874 B CN 108358874B
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- C07D305/00—Heterocyclic compounds containing four-membered rings having one oxygen atom as the only ring hetero atoms
- C07D305/02—Heterocyclic compounds containing four-membered rings having one oxygen atom as the only ring hetero atoms not condensed with other rings
- C07D305/10—Heterocyclic compounds containing four-membered rings having one oxygen atom as the only ring hetero atoms not condensed with other rings having one or more double bonds between ring members or between ring members and non-ring members
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- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
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- 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
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Abstract
The invention relates to a multi-stage production method in diketene production, which comprises the following steps: a. conveying the exhausted air after cracking absorption to a No. 1-3 circulating cooling tank, opening a water ring vacuum pump for circulating cooling absorption, collecting the absorption liquid into a seed tank when the concentration of acetic acid in the absorption liquid reaches 15%, pumping the absorption liquid in the seed tank into a dilute acetic acid large tank, and then entering a concentration working section for concentration; b. after the hydrolyzed waste gas is absorbed by a water washing tower, the waste gas from the water washing tower is directly sent to a sodium hydroxide absorption tower to be neutralized and absorbed with the butyl ester recovered waste water and sodium hydroxide liquid, the absorbed waste gas (PH is more than 8) is directly emptied, and the waste liquid is conveyed to a decontamination water station; c. the liquid after hydrolysis and the liquid in the water washing tower enter a dilute acetic acid vat and enter a concentration working section. The invention has the advantages that the consumption of glacial acetic acid and raw materials is reduced in the system; the waste gas and sewage generated in the production process are digested and absorbed, and the aims of energy conservation, emission reduction and environment-friendly production are finally achieved.
Description
Technical Field
The invention belongs to the technical field of chemical production, relates to a diketene production method, and particularly relates to extraction and recovery of a working solution of a water ring pump type vacuum pump and recovery and utilization of waste gas in diketene production, and a recovery device for multi-stage production in diketene production.
Background
Diketene (C4H 4O 2), also known as acetyl ketene, is colorless or yellowish liquid, has strong pungent smell, is an important intermediate in organic synthesis due to the fact that the diketene structure contains two double bonds and has high unsaturation, and is widely applied to industries such as medicine, pesticide, dye, food and the like.
The synthesis method of diketene is various, and the most widely used method at present is the acetic acid cracking method. Negative pressure production is mostly adopted in the process of producing the diketene by the acetic acid cracking method, and the main equipment for providing the negative pressure in the process of producing the diketene is a water ring pump type vacuum pump. The main working solution of the water ring pump type vacuum pump is water, which mainly comprises acetic anhydride, acetic acid, acetone, butyl ester, diketene and the like in the circulating process, and the solution has pungent smell, so that the solution not only needs to be treated at a high cost, but also pollutes the environment; in addition, a certain amount of waste water is discharged after acetone recovery, butyl ester recovery, acetic acid recovery and dilute acid recovery in the original process, and in the process of recovering the dilute acid, the acetone and the butyl ester, the discharged waste water contains a large amount of water, a small amount of acetic acid and butyl acetate and a small amount of acetone, so that the sewage treatment cost is increased, and energy is wasted. Therefore, how to realize the extraction and recovery of the working solution of the water ring pump type vacuum pump and the recovery and utilization of the waste gas becomes a difficult problem to be solved urgently in the ketene dimer industry.
Disclosure of Invention
The invention aims to further improve the yield of diketene and realize the extraction and recovery of working solution of a water ring pump type vacuum pump and the recovery and utilization of waste gas on the basis of unchanged feeding amount.
In order to solve the problems, the invention adopts the technical scheme that:
a recovery unit that multiplex section produced in diketene production, includes current diketene apparatus for producing, its characterized in that includes:
a. a seed tank, wherein the inlet of the seed tank is connected with the bottoms of a 1# circulating cooling tank, a 2# circulating cooling tank and a 3# circulating cooling tank in a diketene production device by pipelines, each circulating cooling tank is connected with a water ring vacuum pump by a pipeline, the outlet of the seed tank is connected with a seed pump, and the outlet of the seed pump is connected with a dilute acetic acid big tank by a pipeline;
b. the outlet of the dilute acetic acid big tank is connected with a concentration device in the diketene production device through a pipeline, and the inlet of the dilute acetic acid big tank is respectively connected with the bottom of a hydrolysis system, the bottom of a washing tower and the bottom of an acetone purification device in the diketene production device through pipelines;
c. the air inlet of the sodium hydroxide absorption tower is connected with the top of a water washing tower in the diketene production device, absorption liquid in the sodium hydroxide absorption tower is from waste liquid of a butyl ester recovery device and sodium hydroxide solution conveyed through a pipeline, the top of the sodium hydroxide absorption tower is communicated with the outside atmosphere through a pipeline and used for discharging air, and the bottom of the sodium hydroxide absorption tower is connected to a sewage treatment station through a pipeline;
d. the air outlets of an acetone purification secondary cooler, an acetone purification primary condenser, a concentration cooler and a concentration condenser in the diketene production device are respectively connected to the air inlet of the water washing tower by pipelines.
A multi-stage production method in diketene production comprises the steps of cracking, condensing, absorbing, polymerizing, rectifying, recycling and treating residue DK, hydrolyzing, recycling dilute acid, and concentrating to produce diketene, and is characterized by comprising the following steps:
1. delivering desalted water to the No. 1 circulating cooling tank, the No. 2 circulating cooling tank and the No. 3 circulating cooling tank respectively for water sealing and coolant use, delivering the vent gas (acetic acid and ethylene) after cracking and absorption to the No. 1 circulating cooling tank, the No. 2 circulating cooling tank and the No. 3 circulating cooling tank, opening No. 1 water-ring vacuum pump, No. 2 water-ring vacuum pump and No. 3 water-ring vacuum pump for circulating cooling absorption, when the concentration of acetic acid in the absorption liquid at the bottom of the circulating cooling tank reaches 15%, introducing negative pressure into the seed tank, collecting the absorption liquid in the 1# circulating cooling tank, the 2# circulating cooling tank and the 3# circulating cooling tank into the seed tank by using the seed tank as an intermediate, when the absorption liquid in the seeding tank reaches 2/3 of the volume of the seeding tank, pumping the absorption liquid in the seeding tank into a dilute acetic acid vat by using a seed pump, and then enabling the absorption liquid in the dilute acetic acid vat to enter a concentration working section for concentration;
2. after the hydrolyzed waste gas is absorbed by a water washing tower, directly feeding the waste gas (acid, acetone, butyl ester and carbon dioxide) from the water washing tower into a sodium hydroxide absorption tower to be neutralized and absorbed by waste water generated in the butyl ester recovery process and sodium hydroxide liquid from the tower top; directly discharging the waste gas (PH is more than 8) absorbed by the sodium hydroxide absorption tower, conveying the waste liquid absorbed by the sodium oxide absorption tower to a decontamination water station when the liquid level is higher than 80cm and the pH is always maintained to be more than 8;
3. the hydrolyzed liquid and the liquid in the water washing tower enter a dilute acetic acid big tank through pipelines, the liquid in the dilute acetic acid big tank sequentially enters a concentration working section and a recovery working section, the acetic acid is concentrated, and the butyl ester and the acetone are recovered; and the wastewater generated in the concentration working section enters a recovery working section after being subjected to membrane separation treatment, participates in the recovery process of butyl ester and acetone, and is sent to a water washing tower and a sodium hydroxide absorption tower for recycling through pipelines.
The invention has the advantages that the seed pump is utilized to collect the working fluid of the water-ring vacuum pump into the dilute acid vat for the concentration post; the consumption of glacial acetic acid and raw materials is reduced in the system; the waste gas and sewage generated in the production process are digested and absorbed, and the aims of energy conservation, emission reduction and environment-friendly production are finally achieved.
Description of the drawings:
FIG. 1 is a schematic diagram of a multi-stage production technology in diketene production provided by the invention.
Detailed description of the invention
A multi-stage production recovery device in diketene production comprises the following parts:
a. the inlet of the seed tank is connected with the bottoms of the 1# circulating cooling tank, the 2# circulating cooling tank and the 3# circulating cooling tank by pipelines, each circulating cooling tank is connected with a water ring vacuum pump by a pipeline, the seed tank is connected with a seed pump, and the outlet of the seed pump is connected with a dilute acetic acid big tank by a pipeline;
b. the outlet of the dilute acetic acid big tank is connected with the concentration device through a pipeline, and the inlet of the dilute acetic acid big tank is respectively connected with the bottom of the hydrolysis system, the bottom of the washing tower and the bottom of the acetone purification device through pipelines;
c. the air inlet of the sodium hydroxide absorption tower is connected with the top of the water washing tower, absorption liquid in the sodium hydroxide absorption tower is from waste liquid of a butyl ester recovery device and sodium hydroxide solution conveyed through a pipeline, the top of the sodium hydroxide absorption tower is communicated with the outside atmosphere through a pipeline and used for exhausting air, and the bottom of the sodium hydroxide absorption tower is connected to a sewage treatment station through a pipeline;
d. and respectively connecting the air outlets of the acetone purification secondary cooler, the acetone purification primary condenser, the concentration cooler and the concentration condenser to the air inlet of the water washing tower by pipelines.
A multi-stage production method in diketene production comprises the following basic process steps: cracking, condensation, absorption, polymerization, rectification, residue DK recovery treatment, hydrolysis, dilute acid recovery and concentration, and the method mainly comprises the following operation steps:
1. 0.5 ton of desalted water is respectively conveyed to the No. 1 circulating cooling tank, the No. 2 circulating cooling tank and the No. 3 circulating cooling tank to be used as water seal and coolant, the vent gas (acetic acid and ethylene) after cracking and absorption is conveyed to the No. 1 circulating cooling tank, the No. 2 circulating cooling tank and the No. 3 circulating cooling tank, opening No. 1 water-ring vacuum pump, No. 2 water-ring vacuum pump and No. 3 water-ring vacuum pump for circulating cooling absorption, when the concentration of acetic acid in the absorption liquid at the bottom of the circulating cooling tank reaches 15 percent, introducing negative pressure of-75 to-90 KPa to a seed pump, collecting the absorption liquid in the circulating cooling tank into a seed tank by using the seed tank as an intermediate, when the absorption liquid in the seeding tank reaches 2/3 of the volume of the seeding tank, pumping the absorption liquid in the seeding tank into a dilute acid large tank by using a seed pump, and then enabling the absorption liquid in the dilute acetic acid large tank to enter a concentration working section for concentration;
2. after gas generated by hydrolysis is absorbed by a water washing tower, acetone (15%), butyl ester (15%) and acetic acid (within 10% of acetic acid) in absorption liquid at the bottom of the water washing tower enter a dilute acetic acid big tank through a pipeline, the dilute acetic acid big tank enters a concentration system again, the gas (butyl acetate and acetic acid) absorbed by the water washing tower is sent to a sodium hydroxide absorption tower (10% sodium hydroxide), waste liquid and sodium hydroxide solution generated by recycling the butyl ester in the sodium hydroxide absorption tower are neutralized and absorbed, waste gas (PH is more than 8) absorbed by the sodium hydroxide absorption tower is directly emptied, the liquid level of the waste liquid neutralized and absorbed by the sodium oxide absorption tower is higher than 80cm, and the gas is conveyed to a decontamination water station when the pH is maintained to be more than 8 all the time;
3. the liquid of the dilute acetic acid vat enters a concentration system, 1800 Kg of dilute acetic acid is put in every hour, the temperature of a condenser and a cooler in the concentration production process is 10-50 ℃, 1200 Kg of 85 percent of dilute acetic acid is obtained, 600 Kg of waste water is generated, the waste water is separated, and the waste water after separating and recycling acetic acid, butyl ester and acetone is used as absorption liquid of a water washing tower and a sodium hydroxide absorption tower;
4. in the dilute acid concentration working section, after entering a water washing tower for absorption, the vent gas (butyl ester and acetic acid) cooled by a concentration condenser and a concentration cooler is returned to enter a dilute acid large tank through a pipeline, liquid phase acetone (15%) butyl ester (15%) and acetic acid (10%) are sent to the top of a sodium hydroxide absorption tower for use as absorption liquid after passing through a butyl ester recovery device (with the top temperature of 96-100 ℃) and an acetone recovery device (with the top temperature of 76-80 ℃), butyl ester is recycled to a concentration system, acetone enters a dilute acetone tank, dilute acetone is purified by an acetone purification device (with the top temperature of 56-60 ℃ and the bottom temperature of 80-90 ℃) to produce more than 98.5% of finished acetone, the gas phase purified by the acetone purification device is conveyed to an absorption tower, the gas phase absorbed by the absorption tower is sent to the 10% sodium hydroxide absorption tower for neutralization absorption (with the PH being more than 8), so that the acetone butyl ester and the acetic acid are recycled in advance.
The situation of the reduction of raw material consumption and the comparison of acetone yield before and after the adoption of multi-stage production
| Name (R) | Before production by adopting multiple stages | After production by adopting multiple stages |
| Consumption of glacial acetic acid | 1.81/ton | 1.73 ton/ton |
| Consumption of butyl ester | 0.01 ton | 0.003 ton |
| 45% acetone yield | About 280 (yearly) fold (98% acetone 128 ton) | About 1200 (per year) (98% acetone 551 tons) |
Claims (1)
1. A multi-stage production method in diketene production comprises the steps of cracking, condensing, absorbing, polymerizing, rectifying, residue recovery processing, hydrolyzing, dilute acid recovery and concentrating to produce diketene, and is characterized in that the following devices are adopted:
a. a seed tank, wherein the inlet of the seed tank is connected with the bottoms of a 1# circulating cooling tank, a 2# circulating cooling tank and a 3# circulating cooling tank in a diketene production device by pipelines, each circulating cooling tank is connected with a water ring vacuum pump by a pipeline, the outlet of the seed tank is connected with a seed pump, and the outlet of the seed pump is connected with a dilute acetic acid big tank by a pipeline;
b. the outlet of the dilute acetic acid big tank is connected with a concentration device in the diketene production device through a pipeline, and the inlet of the dilute acetic acid big tank is respectively connected with the bottom of a hydrolysis system, the bottom of a washing tower and the bottom of an acetone purification device in the diketene production device through pipelines;
c. the air inlet of the sodium hydroxide absorption tower is connected with the top of a water washing tower in the diketene production device, absorption liquid in the sodium hydroxide absorption tower is from waste liquid of a butyl ester recovery device and sodium hydroxide solution conveyed through a pipeline, the top of the sodium hydroxide absorption tower is communicated with the outside atmosphere through a pipeline and used for discharging air, and the bottom of the sodium hydroxide absorption tower is connected to a sewage treatment station through a pipeline;
d. respectively connecting the air outlets of an acetone purification secondary cooler, an acetone purification primary condenser, a concentration cooler and a concentration condenser in the diketene production device to the air inlet of the water washing tower by using pipelines;
the method comprises the following steps:
(1) delivering desalted water to the No. 1 circulating cooling tank, the No. 2 circulating cooling tank and the No. 3 circulating cooling tank respectively to be used as water seal and coolant, delivering the vent gas after cracking and absorption to the No. 1 circulating cooling tank, the No. 2 circulating cooling tank and the No. 3 circulating cooling tank, opening No. 1 water-ring vacuum pump, No. 2 water-ring vacuum pump and No. 3 water-ring vacuum pump for circulating cooling absorption, when the concentration of acetic acid in the absorption liquid at the bottom of the circulating cooling tank reaches 15%, introducing negative pressure into the seed tank, collecting the absorption liquid in the 1# circulating cooling tank, the 2# circulating cooling tank and the 3# circulating cooling tank into the seed tank by using the seed tank as an intermediate, when the absorption liquid in the seeding tank reaches 2/3 of the volume of the seeding tank, pumping the absorption liquid in the seeding tank into a dilute acetic acid vat by using a seed pump, and then enabling the absorption liquid in the dilute acetic acid vat to enter a concentration working section for concentration;
(2) after the hydrolyzed waste gas is absorbed by a water scrubber, directly feeding the waste gas from the water scrubber into a sodium hydroxide absorption tower to neutralize and absorb the waste water generated in the butyl ester recovery process and the sodium hydroxide liquid from the tower top; directly emptying the waste gas with the pH value of more than 8 after being absorbed by a sodium hydroxide absorption tower, conveying the waste liquid absorbed by the sodium hydroxide absorption tower to a decontamination water station when the liquid level is higher than 80cm and the pH value is always maintained to be more than 8;
(3) the hydrolyzed liquid and the liquid in the water washing tower enter a dilute acetic acid vat through pipelines, the liquid in the dilute acetic acid vat sequentially enters a concentration working section and a recovery working section, the acetic acid is concentrated, and the butyl ester and the acetone are recovered respectively; and the wastewater generated in the concentration working section enters a recovery working section after being subjected to membrane separation treatment, participates in the recovery process of butyl ester and acetone, and is sent to a water washing tower and a sodium hydroxide absorption tower for recycling through pipelines.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201810038346.9A CN108358874B (en) | 2018-01-13 | 2018-01-13 | Multi-section production method and device for diketene |
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| CN201810038346.9A CN108358874B (en) | 2018-01-13 | 2018-01-13 | Multi-section production method and device for diketene |
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| CN108358874B true CN108358874B (en) | 2022-02-15 |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB702913A (en) * | 1950-12-13 | 1954-01-27 | Courtaulds Ltd | Improvements in and relating to the production of diketene |
| CN103588734A (en) * | 2013-11-01 | 2014-02-19 | 安徽金禾实业股份有限公司 | Recovery method and recovery device of butyl ester and acetone in ketene dimer production |
| CN104402670A (en) * | 2014-09-27 | 2015-03-11 | 安徽金禾实业股份有限公司 | Clean production method of diketene |
| CN104592172A (en) * | 2015-01-08 | 2015-05-06 | 青岛科技大学 | Diketene preparation device and diketene preparation method |
| CN106349190A (en) * | 2016-08-30 | 2017-01-25 | 安徽金禾实业股份有限公司 | Method for extracting ketene dimer by rectifying residues and pumped liquid |
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2018
- 2018-01-13 CN CN201810038346.9A patent/CN108358874B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB702913A (en) * | 1950-12-13 | 1954-01-27 | Courtaulds Ltd | Improvements in and relating to the production of diketene |
| CN103588734A (en) * | 2013-11-01 | 2014-02-19 | 安徽金禾实业股份有限公司 | Recovery method and recovery device of butyl ester and acetone in ketene dimer production |
| CN104402670A (en) * | 2014-09-27 | 2015-03-11 | 安徽金禾实业股份有限公司 | Clean production method of diketene |
| CN104592172A (en) * | 2015-01-08 | 2015-05-06 | 青岛科技大学 | Diketene preparation device and diketene preparation method |
| CN106349190A (en) * | 2016-08-30 | 2017-01-25 | 安徽金禾实业股份有限公司 | Method for extracting ketene dimer by rectifying residues and pumped liquid |
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