CN111004393A - Washing water circulation process for polyphenylene sulfide production - Google Patents
Washing water circulation process for polyphenylene sulfide production Download PDFInfo
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- CN111004393A CN111004393A CN201911300774.5A CN201911300774A CN111004393A CN 111004393 A CN111004393 A CN 111004393A CN 201911300774 A CN201911300774 A CN 201911300774A CN 111004393 A CN111004393 A CN 111004393A
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G75/00—Macromolecular compounds obtained by reactions forming a linkage containing sulfur with or without nitrogen, oxygen, or carbon in the main chain of the macromolecule
- C08G75/02—Polythioethers
- C08G75/0204—Polyarylenethioethers
- C08G75/0277—Post-polymerisation treatment
- C08G75/0281—Recovery or purification
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/02—Treatment of water, waste water, or sewage by heating
- C02F1/04—Treatment of water, waste water, or sewage by heating by distillation or evaporation
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2103/00—Nature of the water, waste water, sewage or sludge to be treated
- C02F2103/34—Nature of the water, waste water, sewage or sludge to be treated from industrial activities not provided for in groups C02F2103/12 - C02F2103/32
- C02F2103/36—Nature of the water, waste water, sewage or sludge to be treated from industrial activities not provided for in groups C02F2103/12 - C02F2103/32 from the manufacture of organic compounds
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2301/00—General aspects of water treatment
- C02F2301/08—Multistage treatments, e.g. repetition of the same process step under different conditions
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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
- Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
- Y02A20/00—Water conservation; Efficient water supply; Efficient water use
- Y02A20/124—Water desalination
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- Environmental & Geological Engineering (AREA)
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- Hydrology & Water Resources (AREA)
- General Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Heat Treatment Of Water, Waste Water Or Sewage (AREA)
Abstract
The invention discloses a washing water circulation process for polyphenylene sulfide production, which comprises a rectification recovery water circulation system, a washing water circulation system, a condensed water circulation system and a washing water supplement system; the rectification recycling water circulating system is mainly used for recycling water reaching the quality of desalted water by rectifying mixed materials containing salt, organic matters and water; the washing water circulating system comprises a front-end washing water circulating system and a rear-end washing water circulating system, the front-end washing water circulating system collects primary washing water, the primary washing water is introduced into the synthetic slurry, the rear-end washing water circulating system collects nth-stage washing water, the nth-stage washing water is added into the (n-x) stage washing water process, wherein x is more than or equal to 1; the condensed water circulating system comprises a production evaporation condensed water circulating system and an auxiliary production evaporation condensed water circulating system, and the circulating water of the condensed water circulating system is added into a washing process of any level; the washing water replenishing system is desalted water. The invention has the advantages of simple structure, convenient operation, effective recovery and energy conservation.
Description
Technical Field
The invention relates to the technical field of chemical equipment, in particular to a washing water circulation process for polyphenylene sulfide production.
Background
In the production process of polyphenylene sulfide, in order to guarantee the purity of a product, multistage washing is needed after reaction synthesis is completed, washing water is used in the washing process, the product can be washed by the washing water, and impurities such as oligomer, solvent, inorganic salt and the like remained on the product after production are washed, so that the cleanness, purity and quality of the product are guaranteed.
At the present stage, a large amount of raw water is added in the washing process, 8-10 square of water is required for washing per ton of products on average, the washing process is divided into multiple stages, the concentration of impurities contained in the washing water generated after washing at each stage is gradually reduced, the concentration is higher when the stage is closer to the front, under most conditions, all stages of washing water (especially the stage is closer to the front) can not be recovered, if the washing water is not recovered, the washing water containing more impurities can form a large amount of high-salt waste water, the pollution to the environment is larger, in addition, the water after washing has larger economic benefits, at the present stage, along with the increase of environmental protection, enterprises mostly recover and separate waste and liquid in the production process, the washing water washing is also involved in the recovery and separation, no matter whether the products or recovered substances, at the present stage, the recovery of the washing water of most enterprises only stays at the washing water at the rear stage, the water is cleaner and convenient to recover, but the washing water with larger concentration and the rectification recovered water are directly discharged, so that the environmental protection problem is prominent.
Disclosure of Invention
To the deficiency of the prior art, the technical problem to be solved by the present patent application is: how to provide a washing water circulation process for polyphenylene sulfide production, which has simple structure, convenient operation, effective recovery and energy saving.
In order to achieve the purpose, the invention adopts the following technical scheme:
a washing water circulation process for polyphenylene sulfide production comprises a rectification recovery water circulation system, a washing water circulation system, a condensed water circulation system and a washing water supplement system;
the rectification recycling water circulation system mainly washes washing water of polyphenylene sulfide finished products after centrifugal separation of polyphenylene sulfide synthetic slurry and liquid phase mixed liquid after separation of the synthetic slurry to carry out step-by-step separation and recycle on the generated recycling water. The mixed liquid mainly contains organic matters containing salt, NMP and the like and water. The mixed material is desalted through forced evaporation to obtain a solvent and water, and the solvent is recovered through rectification to recover water, wherein the recovered water reaches the quality of desalted water.
The washing water circulating system comprises a front-end washing water circulating system and a rear-end washing water circulating system, the front-end washing water circulating system collects primary washing water, the primary washing water is introduced into the synthetic slurry, the rear-end washing water circulating system collects nth-stage washing water, the nth-stage washing water is added into the (n-x) stage washing water process, wherein x is more than or equal to 1;
the condensed water circulating system comprises a production evaporation condensed water circulating system and an auxiliary production evaporation condensed water circulating system, and the circulating water of the condensed water circulating system is added into a washing process of any level;
the washing water replenishing system is desalted water.
Furthermore, a first water storage tank is arranged in the front-end washing water circulating system and used for storing primary washing water, the first water storage tank is connected with the primary washing water process through a first feeding pipe, and the first water storage tank is connected with the synthetic slurry tank through a first discharging pipe.
Furthermore, the rear end washing water circulation system is provided with a second water storage tank, the second water storage tank is connected with the nth stage washing water process through a second feeding pipe, wherein n is greater than 1, and the second water storage tank is connected with each stage washing water process through a second discharging pipe.
Furthermore, the production evaporation condensed water circulating system is used for recovering gas evaporated in the production process to a condensed water storage tank through condensation, and the condensed water storage tank is connected with all stages of washing procedures through a fourth water outlet pipe.
Furthermore, the auxiliary production evaporation condensed water circulating system is used for recovering and condensing the steam introduced into the drying mechanism and the heat preservation mechanism and introducing the steam into a condensed water storage tank.
Furthermore, the desalted water is stored in a desalted water storage tank, and the desalted water storage tank is connected with all stages of washing procedures through a fourth water outlet pipe.
Further, the device also comprises a pump and an electromagnetic valve.
The washing water circulation process for polyphenylene sulfide production provided by the invention can fully recycle the washing water flushed into the equipment, especially the primary washing water is flushed into the synthetic slurry, the impurities such as low polymer, solvent, inorganic salt and the like in the synthetic slurry are diluted and dissolved, so that the method is used as a basis for subsequent washing and separation and avoids the problems that in the separation process, under the condition that the concentrations of impurities such as oligomer, solvent, inorganic salt and the like are too high to be effectively separated, all levels of washing water can be reused as washing water after being recovered, because the interior only contains the elements generated by the product and other elements capable of reacting with the product can not be brought in, the quality of the product can not be influenced, in addition, after washing, the temperature of water is increased, and compared with newly added desalted water, the process of temperature rise is omitted, and the energy consumption is reduced; the water vapor evaporated in the equipment and the condensed water obtained by the heat exchange of the water vapor for heat preservation and drying can be added with the washing water, so that the utilization rate is improved.
Drawings
FIG. 1 is a frame diagram of a washing water circulation process for polyphenylene sulfide production disclosed in the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments.
Referring to fig. 1, a washing water circulation process for polyphenylene sulfide production comprises a rectification recovery water circulation system, a washing water circulation system, a condensed water circulation system and a washing water supplement system; the rectification recycling water circulation system mainly washes washing water of polyphenylene sulfide finished products after centrifugal separation of polyphenylene sulfide synthetic slurry and liquid phase mixed liquid after separation of the synthetic slurry to carry out step-by-step separation and recycle on the generated recycling water. The mixed liquid mainly contains organic matters containing salt, NMP and the like and water. The mixed material is desalted through forced evaporation to obtain a solvent and water, and the solvent is recovered through rectification to recover water, wherein the recovered water reaches the quality of desalted water; the washing water circulating system comprises a front-end washing water circulating system and a rear-end washing water circulating system, the front-end washing water circulating system collects primary washing water, the primary washing water is introduced into the synthetic slurry, the rear-end washing water circulating system collects nth-stage washing water, the nth-stage washing water is added into the (n-x) stage washing water process, wherein x is more than or equal to 1; the condensed water circulating system comprises a production evaporation condensed water circulating system and an auxiliary production evaporation condensed water circulating system, and the circulating water of the condensed water circulating system is added into a washing process of any level; the washing water replenishing system is desalted water.
Specifically, be provided with first water storage tank in the front end washing water circulating system, first water storage tank is used for saving elementary washing water, be connected with elementary washing water process through first inlet pipe on the first water storage tank, first water storage tank is through first outlet pipe and synthetic slurry tank.
Specifically, the rear end washing water circulation system is provided with a second water storage tank, the second water storage tank is connected with the nth-stage washing water process through a second feeding pipe, wherein n is greater than 1, and the second water storage tank is connected with each stage washing water process through a second discharging pipe.
Specifically, the production evaporation condensed water circulating system is used for recovering gas evaporated in the production process and recovering the gas to a condensed water storage tank through condensation, and the condensed water storage tank is connected with all stages of washing procedures through a fourth water outlet pipe.
Specifically, the auxiliary production evaporation condensed water circulating system is used for recovering steam introduced into the drying mechanism and the heat preservation mechanism, exchanging heat, condensing the steam, and introducing the steam into a condensed water storage tank.
Specifically, the desalted water is stored in a desalted water storage tank, and the desalted water storage tank is connected with all stages of washing procedures through a fourth water outlet pipe.
In particular, the device also comprises a pump and an electromagnetic valve.
Specifically, the automatic water supply device further comprises a PLC (programmable logic controller), wherein the PLC is S-700, and the PLC is electrically connected with the pump and the electromagnetic valve, so that automatic control is realized, and the automation degree and the water supplement precision are improved.
The washing water circulation process for polyphenylene sulfide production provided by the invention can fully recycle the washing water entering the equipment, especially the primary washing water is utilized and flushed into the synthetic slurry, the impurities such as solvent, inorganic salt and the like in the synthetic slurry are diluted and dissolved, so that the method is a basis for subsequent washing and separation and avoids the problems that in the separation process, under the condition that the concentrations of impurities such as oligomer, solvent, inorganic salt and the like are too high to be effectively separated, all levels of washing water can be reused as washing water after being recovered, because the interior only contains the elements generated by the product and other elements capable of reacting with the product can not be brought in, the quality of the product can not be influenced, in addition, after washing, the temperature of water is increased, and compared with newly added desalted water, the process of temperature rise is omitted, and the energy consumption is reduced; the water vapor evaporated in the equipment and the water vapor used for heat preservation and drying can be added with washing water after heat exchange and condensation, so that the utilization rate is improved.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.
Claims (8)
1. A washing water circulation process for polyphenylene sulfide production is characterized by comprising a rectification recovery water circulation system, a washing water circulation system, a condensed water circulation system and a washing water supplement system;
the rectification recycling water circulation system is mainly used for recycling water which reaches the quality of desalted water through rectification of a mixed material containing salt, organic matters and water. The recovered water directly enters a washing water replenishing system to be used as washing raw water.
The washing water circulating system comprises a front-end washing water circulating system and a rear-end washing water circulating system, the front-end washing water circulating system collects primary washing water, the primary washing water is introduced into the synthetic slurry, the rear-end washing water circulating system collects nth-stage washing water, the nth-stage washing water is added into the (n-x) stage washing water process, wherein x is more than or equal to 1;
the condensed water circulating system comprises a production evaporation condensed water circulating system and an auxiliary production evaporation condensed water circulating system, and the circulating water of the condensed water circulating system is added into a washing process of any level;
the washing water replenishing system is desalted water.
2. The washing water circulation process for polyphenylene sulfide production as claimed in claim 1, wherein the rectification recycling water circulation system mainly washes washing water of polyphenylene sulfide finished products after centrifugal separation of polyphenylene sulfide synthetic slurry and recycling water generated by stepwise separation of mixed liquid of liquid phase after separation of synthetic slurry. The mixed liquid mainly contains organic matters containing salt, NMP and the like and water. The mixed material is desalted through forced evaporation to obtain a solvent and water, and the solvent is recovered through rectification to recover water, wherein the recovered water reaches the quality of desalted water. The recovered water directly enters a washing water replenishing system to be used as washing raw water.
3. The washing water circulation process for polyphenylene sulfide production as claimed in claim 1, wherein a first water storage tank is arranged in the front end washing water circulation system, the first water storage tank is used for storing primary washing water, the first water storage tank is connected with the primary washing water process through a first feeding pipe, and the first water storage tank is connected with the synthetic slurry tank through a first discharging pipe.
4. The washing water circulation process for polyphenylene sulfide production as claimed in claim 2, wherein the back-end washing water circulation system is provided with a second water storage tank, the second water storage tank is connected with the nth stage washing water process through a second feeding pipe, wherein n is greater than 1, and the second water storage tank is connected with each stage washing water process through a second discharging pipe.
5. The washing water circulation process for polyphenylene sulfide production as claimed in claim 3, wherein the production evaporation condensed water circulation system is used for recovering evaporated gas in the production process, and the evaporated gas is recovered to a condensed water storage tank through condensation, and the condensed water storage tank is connected with all stages of washing water procedures through a fourth water outlet pipe.
6. The washing water circulation process for polyphenylene sulfide production as claimed in claim 4, wherein the auxiliary production evaporation condensed water circulation system is used for recovering the steam introduced into the drying mechanism and the heat preservation mechanism, condensing the steam after heat exchange, and introducing the steam into the condensed water storage tank.
7. The washing water circulation process for polyphenylene sulfide production according to claim 5, wherein the desalted water is stored in a desalted water storage tank, and the desalted water storage tank is connected with all stages of washing water processes through a fourth water outlet pipe.
8. The washing water circulation process for polyphenylene sulfide production as claimed in claim 6, further comprising a pump and a solenoid valve.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911300774.5A CN111004393A (en) | 2019-12-17 | 2019-12-17 | Washing water circulation process for polyphenylene sulfide production |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201911300774.5A CN111004393A (en) | 2019-12-17 | 2019-12-17 | Washing water circulation process for polyphenylene sulfide production |
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| CN111004393A true CN111004393A (en) | 2020-04-14 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112358096A (en) * | 2020-10-23 | 2021-02-12 | 重庆聚狮新材料科技有限公司 | Refining method for polyphenylene sulfide rectification recovered water |
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| CN101429288A (en) * | 2008-12-09 | 2009-05-13 | 江苏新中投资有限公司 | Method for treating process liquid generated in production process of polyphenylene sulfide |
| RU2437846C1 (en) * | 2010-05-04 | 2011-12-27 | Открытое акционерное общество "Казанский завод синтетического каучука" (ОАО "КЗСК") | Method of recycling waste water |
| CN102675683A (en) * | 2011-03-18 | 2012-09-19 | 四川得阳工程塑料开发有限公司 | Solvent and catalyst recovery technology in polyphenyl thioether production |
| JP2013245191A (en) * | 2012-05-25 | 2013-12-09 | Dic Corp | Method for producing oligoarylene sulfide and carboxyalkylamino group-containing compound |
| JP2014024981A (en) * | 2012-07-27 | 2014-02-06 | Dic Corp | Method for manufacturing a polyarylene sulfide resin |
| CN106750299A (en) * | 2017-01-13 | 2017-05-31 | 四川中科兴业高新材料有限公司 | A kind of preparation method of inexpensive polyphenylene sulfide |
| CN109535425A (en) * | 2018-11-27 | 2019-03-29 | 德阳科吉高新材料有限责任公司 | A kind of polyphenylene sulfide resin production process |
| CN109929111A (en) * | 2017-12-18 | 2019-06-25 | 广安玖源新材料有限公司 | A method of polyphenylene sulfide is collected from polyphenylene sulfide slurry |
-
2019
- 2019-12-17 CN CN201911300774.5A patent/CN111004393A/en active Pending
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000191785A (en) * | 1998-12-24 | 2000-07-11 | Kureha Chem Ind Co Ltd | Production of polyarylene sulfide |
| CN101429288A (en) * | 2008-12-09 | 2009-05-13 | 江苏新中投资有限公司 | Method for treating process liquid generated in production process of polyphenylene sulfide |
| RU2437846C1 (en) * | 2010-05-04 | 2011-12-27 | Открытое акционерное общество "Казанский завод синтетического каучука" (ОАО "КЗСК") | Method of recycling waste water |
| CN102675683A (en) * | 2011-03-18 | 2012-09-19 | 四川得阳工程塑料开发有限公司 | Solvent and catalyst recovery technology in polyphenyl thioether production |
| JP2013245191A (en) * | 2012-05-25 | 2013-12-09 | Dic Corp | Method for producing oligoarylene sulfide and carboxyalkylamino group-containing compound |
| JP2014024981A (en) * | 2012-07-27 | 2014-02-06 | Dic Corp | Method for manufacturing a polyarylene sulfide resin |
| CN106750299A (en) * | 2017-01-13 | 2017-05-31 | 四川中科兴业高新材料有限公司 | A kind of preparation method of inexpensive polyphenylene sulfide |
| CN109929111A (en) * | 2017-12-18 | 2019-06-25 | 广安玖源新材料有限公司 | A method of polyphenylene sulfide is collected from polyphenylene sulfide slurry |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112358096A (en) * | 2020-10-23 | 2021-02-12 | 重庆聚狮新材料科技有限公司 | Refining method for polyphenylene sulfide rectification recovered water |
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