CN105985459A - Method for continuously washing fluorine-containing polymer - Google Patents
Method for continuously washing fluorine-containing polymer Download PDFInfo
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- CN105985459A CN105985459A CN201510089639.6A CN201510089639A CN105985459A CN 105985459 A CN105985459 A CN 105985459A CN 201510089639 A CN201510089639 A CN 201510089639A CN 105985459 A CN105985459 A CN 105985459A
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Abstract
The invention relates to a method for continuously washing a fluorine-containing polymer. The method comprises the following steps that a fluorine-containing polymer emulsion obtained through an emulsion polymerization method serves as the raw material, mechanical demulsification is conducted to obtain a polymer suspension, the polymer suspension is continuously introduced to the lower portion of a washing tower, deionized water is continuously introduced into the upper portion of the washing tower, the fluorine-containing polymer and the deionized water are washed in a countercurrent contact mode, after washing is conducted, the fluorine-containing polymer is discharged from the position higher than a deionized water inlet and then subjected to centrifugal drying to obtain a qualified product, and washing wastewater is discharged from the position lower than a fluorine-containing polymer emulsion inlet. The invention further provides a device for continuously washing the fluorine-containing polymer. According to the method, continuous washing can be conducted on the fluorine-containing polymer under the fully closed condition, and the method has the advantages of being wide in application range, high in washing efficiency, low in water consumption and the like; meanwhile, other impurities cannot be introduced, and the product quality can be improved.
Description
Technical field
The present invention relates to a kind of method washed continuously for fluoropolymer.
Background technology
Fluoropolymer has weatherability, electrical insulating property, chemical-resistant, corrosion resistance and the high and low temperature resistance of excellence, is all widely used in fields such as aviation, automobile, oil and chemical industry.Emulsion polymerization is one of important process of preparing of fluoropolymer, all can use the method that emulsion is polymerized including politef, Kynoar, perfluoroethylene-propylene, tetrafluoraoethylene-hexafluoropropylene copolymer, vinylidene fluoride-hexafluoropropylene copolymer, ethylene-chlorotrifluoro-ethylene copolymer etc..And emulsion to be polymerized topmost shortcoming be that aftertreatment technology is complex, need through filtration, breakdown of emulsion, wash, be dried, the process such as pelletize.Both at home and abroad emulsion after-treatment technology is carried out numerous studies, it is intended to improve production efficiency, reduce production cost.
In the prior art, have described below for washing process after fluoropolymer breakdown of emulsion:
(1) after after traditional fluoropolymer breakdown of emulsion, washing process is resin breakdown of emulsion, add deionized water, open stirring and promote the ion exchange of resin and water, then remove water layer by stratification or the mode such as centrifugal, repeated multiple times until impurities left amount is less than index in resin.The method frequent operation, and detersive efficiency is low, and water consumption is big, it is generally required to the washing of more than 6 times is the most up to standard.
(2) Chinese patent CN102875711A elaborates that polyvinylidene fluoride emulsion prepared by a kind of emulsion polymerization is condensed and the new method of resin washing.This patent thinks that toner particle diameter is less after the cohesion that traditional handicraft obtains, and the resin of cohesion in the pasty state, is unfavorable for that next step washs.This patented invention is by using freezing breakdown of emulsion and mechanical agitation Shearing demulsification united method that emulsion carries out breakdown of emulsion and to obtain particle diameter be the toner about 200 μm, and studies and obtained washing pure water preferable temperature, preferred number of times and single wash preferred time.Although the method decreases washing times and wash time to a certain extent, but to first pass through freezing breakdown of emulsion, the washing of reusable heat water, energy consumption is bigger.
(3) Chinese patent CN102838820A describes the aftertreatment technology of a kind of fluoropolymer.This patent by the emulsion breaking of fluorine resin, wash, be dehydrated, the unit such as aerofluxus is incorporated in a set of extruder with different operating region.Zones of different at extruder realizes different functions.After emulsion being carried out breakdown of emulsion, and breakdown of emulsion with high steam before this, fluoropolymer is molten condition, enters washing dehydration region together with water, and molten fluoropolymer is carried out repeatedly washing dehydration, until surfactant residual is less than 10ppm.Wash qualified rear fluoropolymer entrance vacuum area to be exhausted, moisture content is down to less than 0.1%, enters back into granulator granulation.This method is to wash after fluoropolymer melt again, is not suitable for thermosetting polymer, and cannot obtain powder product.
Summary of the invention
For the deficiencies in the prior art, the present invention provides a kind of method washed continuously for fluoropolymer, comprise the following steps: the fluoropolymer emulsion obtained with emulsion polymerization is as raw material, polymer suspension is obtained after machinery breakdown of emulsion, it is characterized in that, fluoropolymer emulsion is after machinery breakdown of emulsion, it is passed through scrubbing tower bottom continuously, deionized water it is passed through continuously from scrubbing tower top, described fluoropolymer suspension washs with deionized water counter current contacting, wash rear fluoropolymer discharge from the position higher than described deionized water entrance and be dried to obtain qualified products by centrifugation, washes is discharged from the position less than described fluoropolymer emulsion entrance.
Further, the one during described fluoropolymer is politef, Kynoar, perfluoroethylene-propylene, ethylene-chlorotrifluoro-ethylene copolymer, tetrafluoraoethylene-hexafluoropropylene copolymer, vinylidene fluoride-hexafluoropropylene copolymer and tetrafluoroethylene-perfluoro alkyl alkene ether copolymer.
Further, the solid holdup of described fluoropolymer emulsion raw material is 5% ~ 30% g/g.
Further, after breakdown of emulsion, fluoropolymer apparent density is 0.2 g/cm3~0.8g/cm3。
Further, after deionized water described in washing process and described breakdown of emulsion, the ratio of the mass flow of the charging of fluoropolymer suspension is 1:1 ~ 10:1, preferably 1:1 ~ 5:1.
Further, deionized water temperature described in washing process is 10 DEG C ~ 80 DEG C, preferably 25 DEG C ~ 70 DEG C.
Further, in washing process, being passed through gas in the bottom of described scrubbing tower and reduce the fluoropolymer entrainment of washes, described gas is preferably nitrogen.
Further, in washing process, strengthen the suspension to the fluoropolymer in tower and the mixing of deionized water by being arranged on the multiphase flow pump of the tower body of scrubbing tower；Described multiphase flow pump is staggered installation of the tower body both sides at described scrubbing tower symmetrically；For same multiphase flow pump, the height of its entrance is higher than the height of its outlet；And gateway is positioned at the separate space that same baffle plate is formed；Described multiphase flow pump is 2 ~ 50 times with the ratio of the mass flow of the deionized water of described washing, preferably 4 ~ 10 times.
nullThe present invention also provides for a kind of utilizing the described device for fluoropolymer continuous washing method，Including breakdown of emulsion still、Medial launder and scrubbing tower，Described medial launder is arranged between described breakdown of emulsion still and scrubbing tower，Described scrubbing tower includes accumulator still、Tower body and standing tank，Described accumulator still is connected to the bottom of described tower body，Described standing tank is connected to the top of described tower body，It is provided with distributor in described accumulator still，Described distributor is for being passed through being uniformly distributed of gas，Described accumulator still bottom is provided with the outlet of washes，Described tower body bottom is provided with the entrance of fluoropolymer suspension after breakdown of emulsion，Described tower body is internally provided with baffle plate，Described baffle plate is for extending washings and the fluoropolymer suspension time of staying at tower body，Multiple multiphase flow pump it is provided with in the middle part of described tower body，Described multiphase flow pump is staggered installation of the tower body both sides at described scrubbing tower symmetrically，For same multiphase flow pump，The height of its entrance is higher than the height of its outlet，And gateway is positioned at the separate space that same baffle plate is formed，Described tower body top is provided with the entrance of deionized water，Described standing tank top is provided with the outlet washing rear fluoropolymer.Described standing tank is used for resin and the layering of water, reduces the moisture content washing rear resin；Described scrubbing tower tower body is the main place of resin and water generation countercurrent washing；Described accumulator still is used for reducing resin in washes and carries secretly；Described multiphase flow pump, for strengthening the local dip within scrubbing tower tower body, strengthens the mixed effect of resin and deionized water；Described distributor for forming uniform minute bubbles in water by nitrogen.
Compared with prior art, it is an advantage of the current invention that:
(1) provide a kind of method washed continuously for fluoropolymer, while substantially increasing detersive efficiency, also reduce water consumption；
(2) substitute traditional stirring with pump recycle stream, thus strengthen the ion exchange process in washing process, be not only easier to realize industrialization, and new impurity will not be introduced；
(3) introduce nitrogen in wash tower bottoms and produce bubble, it is therefore intended that reducing fluoropolymer entrainment in washes, the most also reducing fluoropolymer apparent density after breakdown of emulsion, advantageously reduce slurry amount.
Accompanying drawing explanation
Fig. 1 is flow process and the schematic diagram of device of the present invention.
In figure: 1 is breakdown of emulsion still；2 is medial launder；3-1 is accumulator still；3-2 is tower body；3-3 is for standing tank；3-11 is distributor；3-21 is baffle plate；3-22 is multiphase flow pump.
Detailed description of the invention
With specific embodiment, the present invention is further described below in conjunction with the accompanying drawings.
Embodiment
1
The polyvinylidene fluoride emulsion that solid holdup is 25% is passed through breakdown of emulsion still, opens stirring breakdown of emulsion complete.Again by the bottom of the polyvinylidene fluoride resin transport pump after breakdown of emulsion to scrubbing tower；After breakdown of emulsion, resin feeding flow is 500kg/h；Washing deionized water consumption is 1000kg/h, and water temperature is 25 DEG C；Opening all multiphase flow pumps, pump discharge is 5000kg/h, washes rear resinous electricity conductance and is less than 5 μ s/cm, and solid holdup is 12%；Washes electrical conductivity is 120 ~ 160 μ s/cm, and solid holdup is less than 0.05%.
Embodiment
2
The perfluoroethylene-propylene emulsion that solid holdup is 15% is passed through breakdown of emulsion still, opens stirring breakdown of emulsion complete.Again by the bottom of exhaustive fluorinated ethylene propylene pump after breakdown of emulsion to scrubbing tower；After breakdown of emulsion, resin feeding flow is 400kg/h；Washing deionized water consumption is 1500kg/h, and water temperature is 65 DEG C；Opening all multiphase flow pumps, pump discharge is that 15000kg/h is constantly passed through nitrogen toward tower reactor distributor, and nitrogen use level is 4m3/h；Washing rear exhaustive fluorinated ethylene propylene electrical conductivity and be less than 2 μ s/cm, solid holdup is 10%；Washes electrical conductivity is 50 ~ 60 μ s/cm, and solid holdup is less than 0.05%.
Embodiment
3
The polyvinylidene fluoride emulsion that solid holdup is 8% is passed through breakdown of emulsion still, opens stirring breakdown of emulsion complete.Again by the bottom of exhaustive fluorinated ethylene propylene pump after breakdown of emulsion to scrubbing tower；After breakdown of emulsion, resin feeding flow is 800kg/h；Washing deionized water consumption is 1000kg/h, and water temperature is 45 DEG C；Opening all multiphase flow pumps, pump discharge is 2000kg/h；Constantly being passed through nitrogen toward tower reactor distributor, nitrogen use level is 2m3/h；Washing rear exhaustive fluorinated ethylene propylene electrical conductivity and be less than 3 μ s/cm, solid holdup is 12%；Washes electrical conductivity is 50 ~ 60 μ s/cm, and solid holdup is less than 0.05%.
Embodiment
4
nullThe present invention also provides for a kind of utilizing the described device for fluoropolymer continuous washing method，Including breakdown of emulsion still 1、Medial launder 2 and scrubbing tower，Described medial launder 2 is arranged between described breakdown of emulsion still 1 and scrubbing tower，Described scrubbing tower includes accumulator still 3-1、Tower body 3-2 and standing tank 3-3，Described accumulator still 3-1 is connected to the bottom of described tower body 3-2，Described standing tank 3-3 is connected to the top of described tower body 3-2，It is provided with distributor 3-11 in described accumulator still 3-1，Described distributor 3-11 is for being passed through being uniformly distributed of gas，Described accumulator still 3-1 bottom is provided with the outlet of washes，Described tower body 3-2 bottom is provided with the entrance of fluoropolymer suspension after breakdown of emulsion，Described tower body 3-2 is internally provided with baffle plate 3-21，Described baffle plate 3-21 is for extending washings and the fluoropolymer suspension time of staying in tower，Multiple multiphase flow pump 3-22 it is provided with in the middle part of described tower body 3-2，Described multiphase flow pump 3-22 is staggered installation of the tower body 3-2 both sides at described scrubbing tower symmetrically，For same multiphase flow pump 3-22，The height of its entrance is higher than the height of its outlet，And gateway is positioned in same baffle plate separate space，Described tower body 3-2 top is provided with the entrance of deionized water，Described standing tank 3-3 top is provided with the outlet washing rear fluoropolymer.Described standing tank 3-3 is used for resin and the layering of water, reduces the moisture content washing rear resin；Described scrubbing tower tower body 3-2 is the main place of resin and water generation countercurrent washing；Described accumulator still 3-1 is used for reducing resin in washes and carries secretly；Described multiphase flow pump 3-22, for strengthening the local dip within scrubbing tower tower body, strengthens the mixed effect of resin and deionized water；Described distributor 3-11 for forming uniform minute bubbles in water by nitrogen.
Claims (9)
1. the method washed continuously for fluoropolymer, comprise the following steps: the fluoropolymer emulsion obtained with emulsion polymerization is as raw material, polymer suspension is obtained after machinery breakdown of emulsion, it is characterized in that, fluoropolymer emulsion is after machinery breakdown of emulsion, it is passed through scrubbing tower bottom continuously, deionized water it is passed through continuously from scrubbing tower top, described fluoropolymer suspension washs with deionized water counter current contacting, wash rear fluoropolymer discharge from the position higher than described deionized water entrance and be dried to obtain qualified products by centrifugation, washes is discharged from the position less than described fluoropolymer emulsion entrance.
A kind of method washed continuously for fluoropolymer, it is characterized in that, described fluoropolymer is the one in politef, Kynoar, perfluoroethylene-propylene, ethylene-chlorotrifluoro-ethylene copolymer, tetrafluoraoethylene-hexafluoropropylene copolymer, vinylidene fluoride-hexafluoropropylene copolymer and tetrafluoroethylene-perfluoro alkyl alkene ether copolymer.
A kind of method washed continuously for fluoropolymer, it is characterised in that the solid holdup of described fluoropolymer emulsion raw material is 5% ~ 30% g/g.
A kind of method washed continuously for fluoropolymer, it is characterised in that after breakdown of emulsion, fluoropolymer apparent density is 0.2 g/cm3~0.8g/cm3。
A kind of method washed continuously for fluoropolymer, it is characterised in that after deionized water described in washing process and described breakdown of emulsion, the ratio of the mass flow of the charging of fluoropolymer suspension is 1:1 ~ 10:1, preferably 1:1 ~ 5:1.
A kind of method washed continuously for fluoropolymer, it is characterised in that deionized water temperature described in washing process is 10 DEG C ~ 80 DEG C, preferably 25 DEG C ~ 70 DEG C.
A kind of method washed continuously for fluoropolymer, it is characterised in that in washing process, is passed through gas and reduces the fluoropolymer entrainment of washes in the bottom of described scrubbing tower, and described gas is preferably nitrogen.
A kind of method washed continuously for fluoropolymer, it is characterised in that in washing process, strengthens the suspension to the fluoropolymer in tower and the mixing of deionized water by being arranged on the multiphase flow pump of the tower body of scrubbing tower；Described multiphase flow pump is staggered installation of the tower body both sides at described scrubbing tower symmetrically；For same multiphase flow pump, the height of its entrance is higher than the height of its outlet, and gateway is positioned at the separate space that same baffle plate is formed；Described multiphase flow pump is 2 ~ 50 times with the ratio of the mass flow of the deionized water of described washing, preferably 4 ~ 10 times.
null9. the device for fluoropolymer continuous washing method utilized described in claim 1，Including breakdown of emulsion still、Medial launder and scrubbing tower，Described medial launder is arranged between described breakdown of emulsion still and scrubbing tower，It is characterized in that，Described scrubbing tower includes accumulator still、Tower body and standing tank，Described accumulator still is connected to the bottom of described tower body，Described standing tank is connected to the top of described tower body，It is provided with distributor in described accumulator still，Described distributor is for being passed through being uniformly distributed of gas，Described accumulator still bottom is provided with the outlet of washes，Described tower body bottom is provided with the entrance of fluoropolymer suspension after breakdown of emulsion，Described tower body is internally provided with baffle plate，Described baffle plate is for extending washings and the fluoropolymer suspension time of staying at tower body，Multiple multiphase flow pump it is provided with in the middle part of described tower body，Described multiphase flow pump is staggered installation of the tower body both sides at described scrubbing tower symmetrically，For same multiphase flow pump，The height of its entrance is higher than the height of its outlet，And gateway is positioned at the separate space that same baffle plate is formed，Described tower body top is provided with the entrance of deionized water，Described standing tank top is provided with the outlet washing rear fluoropolymer.
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| CN201510089639.6A CN105985459B (en) | 2015-02-27 | 2015-02-27 | A method of it is continuously washed for fluoropolymer |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109107221A (en) * | 2018-08-21 | 2019-01-01 | 金发科技股份有限公司 | A kind of liquid-solid extraction purification devices and purification process |
| CN110317286A (en) * | 2018-03-30 | 2019-10-11 | 浙江蓝天环保高科技股份有限公司 | A method of improving polyvinylidene fluoride resin degree of purity |
| CN111450787A (en) * | 2020-03-31 | 2020-07-28 | 无锡银燕化工装备科技有限公司 | Reactor for continuous washing |
| CN114736319A (en) * | 2021-01-07 | 2022-07-12 | 中昊晨光化工研究院有限公司 | Device system and method for purifying polymer from polymerization emulsion |
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| US4128517A (en) * | 1977-11-01 | 1978-12-05 | Pennwalt Corporation | Method of washing polymer latices by aerating |
| US4228005A (en) * | 1977-05-27 | 1980-10-14 | E. I. Du Pont De Nemours And Company | Mechanical dewatering apparatus for elastomer slurries |
| CN102765835A (en) * | 2012-08-14 | 2012-11-07 | 陕西太阳景环保科技有限公司 | Closed multistage purified water device and production process |
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2015
- 2015-02-27 CN CN201510089639.6A patent/CN105985459B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4228005A (en) * | 1977-05-27 | 1980-10-14 | E. I. Du Pont De Nemours And Company | Mechanical dewatering apparatus for elastomer slurries |
| US4128517A (en) * | 1977-11-01 | 1978-12-05 | Pennwalt Corporation | Method of washing polymer latices by aerating |
| CN102765835A (en) * | 2012-08-14 | 2012-11-07 | 陕西太阳景环保科技有限公司 | Closed multistage purified water device and production process |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110317286A (en) * | 2018-03-30 | 2019-10-11 | 浙江蓝天环保高科技股份有限公司 | A method of improving polyvinylidene fluoride resin degree of purity |
| CN109107221A (en) * | 2018-08-21 | 2019-01-01 | 金发科技股份有限公司 | A kind of liquid-solid extraction purification devices and purification process |
| CN111450787A (en) * | 2020-03-31 | 2020-07-28 | 无锡银燕化工装备科技有限公司 | Reactor for continuous washing |
| CN114736319A (en) * | 2021-01-07 | 2022-07-12 | 中昊晨光化工研究院有限公司 | Device system and method for purifying polymer from polymerization emulsion |
| CN114736319B (en) * | 2021-01-07 | 2023-12-26 | 中昊晨光化工研究院有限公司 | Apparatus system and method for purifying polymer from polymeric emulsion |
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Effective date of registration: 20190724 Address after: 312369 No. 1 Jingjiu Road, Shangyu Economic and Technological Development Zone, Hangzhou Bay, Shaoxing City, Zhejiang Province Co-patentee after: Zhejiang Lantian Environment Protecting Sci-Tech Co., Ltd. Patentee after: Sinochem Blue Sky Fluorine Material Co., Ltd. Address before: 312369 Shangyu, Shaoxing, Hangzhou Bay Fine Chemical Industrial Park, No. 31, No. five weft Road, No. Co-patentee before: Zhejiang Lantian Environment Protecting Sci-Tech Co., Ltd. Patentee before: ZHEJIANG CHEMICAL INSTITUTE TECHNOLOGY CO., LTD. |