CN101280476B - Method for recovering NMMO solvent in solvent method fiber production - Google Patents
Method for recovering NMMO solvent in solvent method fiber production Download PDFInfo
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- CN101280476B CN101280476B CN2008103017545A CN200810301754A CN101280476B CN 101280476 B CN101280476 B CN 101280476B CN 2008103017545 A CN2008103017545 A CN 2008103017545A CN 200810301754 A CN200810301754 A CN 200810301754A CN 101280476 B CN101280476 B CN 101280476B
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- nmmo
- resin
- waste liquid
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- LFTLOKWAGJYHHR-UHFFFAOYSA-N N-methylmorpholine N-oxide Chemical compound CN1(=O)CCOCC1 LFTLOKWAGJYHHR-UHFFFAOYSA-N 0.000 title claims abstract description 54
- 238000000034 method Methods 0.000 title claims abstract description 33
- 239000002904 solvent Substances 0.000 title claims abstract description 19
- 238000007380 fibre production Methods 0.000 title abstract description 10
- 239000007788 liquid Substances 0.000 claims abstract description 59
- 239000002699 waste material Substances 0.000 claims abstract description 31
- 239000011347 resin Substances 0.000 claims abstract description 30
- 229920005989 resin Polymers 0.000 claims abstract description 30
- 150000001450 anions Chemical class 0.000 claims abstract description 20
- 238000011084 recovery Methods 0.000 claims abstract description 18
- 239000003729 cation exchange resin Substances 0.000 claims abstract description 13
- NWUYHJFMYQTDRP-UHFFFAOYSA-N 1,2-bis(ethenyl)benzene;1-ethenyl-2-ethylbenzene;styrene Chemical compound C=CC1=CC=CC=C1.CCC1=CC=CC=C1C=C.C=CC1=CC=CC=C1C=C NWUYHJFMYQTDRP-UHFFFAOYSA-N 0.000 claims abstract description 12
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 12
- 150000001768 cations Chemical class 0.000 claims abstract description 9
- 239000000835 fiber Substances 0.000 claims abstract description 7
- 238000001704 evaporation Methods 0.000 claims description 23
- 238000010438 heat treatment Methods 0.000 claims description 16
- 230000000694 effects Effects 0.000 claims description 13
- 238000009834 vaporization Methods 0.000 claims description 13
- 230000008016 vaporization Effects 0.000 claims description 13
- 238000002425 crystallisation Methods 0.000 claims description 8
- 230000008025 crystallization Effects 0.000 claims description 8
- 238000002156 mixing Methods 0.000 claims description 4
- 238000001816 cooling Methods 0.000 claims description 2
- 239000004793 Polystyrene Substances 0.000 abstract description 3
- 239000002253 acid Substances 0.000 abstract description 3
- 229920002223 polystyrene Polymers 0.000 abstract description 3
- 239000002351 wastewater Substances 0.000 abstract description 3
- 238000004519 manufacturing process Methods 0.000 abstract description 2
- -1 acrylic anion Chemical class 0.000 abstract 1
- 239000013078 crystal Substances 0.000 abstract 1
- 239000012535 impurity Substances 0.000 description 10
- 238000003860 storage Methods 0.000 description 10
- 230000008020 evaporation Effects 0.000 description 7
- 229910021645 metal ion Inorganic materials 0.000 description 7
- 239000007787 solid Substances 0.000 description 6
- 238000004040 coloring Methods 0.000 description 4
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 3
- SJRJJKPEHAURKC-UHFFFAOYSA-N N-Methylmorpholine Chemical compound CN1CCOCC1 SJRJJKPEHAURKC-UHFFFAOYSA-N 0.000 description 3
- 230000001112 coagulating effect Effects 0.000 description 3
- 238000001914 filtration Methods 0.000 description 3
- 238000004064 recycling Methods 0.000 description 3
- NIXOWILDQLNWCW-UHFFFAOYSA-N Acrylic acid Chemical class OC(=O)C=C NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 description 2
- PTHCMJGKKRQCBF-UHFFFAOYSA-N Cellulose, microcrystalline Chemical compound OC1C(O)C(OC)OC(CO)C1OC1C(O)C(O)C(OC)C(CO)O1 PTHCMJGKKRQCBF-UHFFFAOYSA-N 0.000 description 2
- YNAVUWVOSKDBBP-UHFFFAOYSA-N Morpholine Chemical compound C1COCCN1 YNAVUWVOSKDBBP-UHFFFAOYSA-N 0.000 description 2
- 229920000297 Rayon Polymers 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 229940023032 activated charcoal Drugs 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 230000029087 digestion Effects 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 239000003456 ion exchange resin Substances 0.000 description 1
- 229920003303 ion-exchange polymer Polymers 0.000 description 1
- 239000010808 liquid waste Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000010812 mixed waste Substances 0.000 description 1
- 238000012856 packing Methods 0.000 description 1
- 239000000049 pigment Substances 0.000 description 1
- 238000001223 reverse osmosis Methods 0.000 description 1
- 238000009987 spinning Methods 0.000 description 1
Classifications
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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
- Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
- Y02P70/50—Manufacturing or production processes characterised by the final manufactured product
- Y02P70/62—Manufacturing or production processes characterised by the final manufactured product related technologies for production or treatment of textile or flexible materials or products thereof, including footwear
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- Treatment Of Water By Ion Exchange (AREA)
- Heat Treatment Of Water, Waste Water Or Sewage (AREA)
Abstract
The invention relates to a recovery method of NMMO waste liquid, and provides a recovery method of NMMO in solvent method fiber production waste liquid. The method comprises the following steps: the NMMO waste liquid passes through a cation resin exchange column and an anion resin exchange column in sequence, is decompressed and evaporated to have the refractive index of 1.480, and is cooled to prepare NMMO containing a crystal water; the cation resin is macroporous or gel type strong acid polystyrene cation exchange resin, and the anion resin is macroporous or gel type weak base acrylic anion resin. Compared with the existing recovery method, the recovery rate of the NMMO waste liquid is improved from 95% to 99.5%, the concentration of NMMO in the discharged waste water after recovery is reduced, steam is saved, and the production cost of fibers is greatly reduced.
Description
Technical field
The present invention relates to the recovery method of a kind of solvent N-methylmorpholine oxide (NMMO), belong to the solvent method fiber production field.
Background technology
Used a large amount of NMMO solvents in the existing fiber production, usually after through spinning and high-temperature digestion process from coagulating bath etc. receive waste liquid in contain following several material usually: N-methylmorpholine oxide (NMMO), suspended impurity (strand and cellulose gel blob of viscose), foreign pigment (coloured catabolite morpholine that NMMO at high temperature produces and N-methylmorpholine etc.) and metal ion (equipment that is in contact with it in from pulp, NMMO and fiber production process, pipeline etc.).For NMMO can be reused, must remove these impurity by recycling engineering, so solvent recovery plays important effect in fiber production.
Domestic existing NMMO method for recovering solvents is that active carbon and reduction vaporization combine, and promptly removes solid impurity by mechanical filter; Activated-charcoal column decolours; Single effect evaporator carries out reduction vaporization, and vacuum degree control is at 15～18KPa, and heating and temperature control is at 110～120 ℃, and evaporating temperature is controlled at 74～76 ℃, and water vapour is recycled by condenser.But aforementioned recovery method water vapour large usage quantity is unfavorable for controlling cost, and solvent recovering rate is not high, and remaining NMMO discharges with waste water, not only contaminated environment but also cause the waste of useful resources.
Summary of the invention
Technical problem to be solved by this invention provides the recovery method of NMMO in a kind of solvent method fiber production.
The present invention solves the problems of the technologies described above the technical scheme of being taked:
Reduction vaporization was to index of refraction 1.480 after the NMMO waste liquid passed through cation exchange resin column, resin anion (R.A.) exchange column successively, and cooling promptly makes the NMMO that contains a crystallization water.
Described resin cation is macroporous type or gel-type highly acid polystyrene cationic ion-exchange resin; Resin anion (R.A.) is macroporous type or gel-type alkalescent acrylic acid series resin anion (R.A.).
Cation exchange resin column flow rate of mobile phase 3～6BV/h is in order to remove metal ion; Resin anion (R.A.) exchange column flow rate of mobile phase 3～6BV/h is in order to remove the catabolite in coloring matter and the fiber production.
Contain a spot of solid impurity (strand and cellulose gel blob of viscose) in the usual solvents method fiber production in the NMMO waste liquid, so the NMMO waste liquid need remove by filter these solid impurities before entering cation exchange resin column.
When the NMMO waste liquid weight percent concentration that reclaims is 8～28%, because the impurity content in the waste liquid is bigger, the NMMO waste liquid is successively by behind cation exchange resin column, the resin anion (R.A.) exchange column, exchange column by resin cation and resin anion (R.A.) mixed packing again, flow rate of mobile phase 3～6BV/h is further to remove the catabolite in metal ion, coloring matter and the fiber production.
The effect of reduction vaporization process is the part moisture that evaporates NMMO solution, adopts triple effect evaporator, and one imitates heating and temperature control at 78～82 ℃, and evaporating temperature is controlled at 68～72 ℃; Two imitate heating and temperature control at 68～72 ℃, and evaporating temperature is controlled at 56～60 ℃; The triple effect heating and temperature control is at 56～60 ℃, and evaporating temperature is controlled at 44～48 ℃; When the remaining NMMO solution index of refraction of evaporation reaches 1.480, the NMMO weight percent content is to stop evaporation at 86.6% o'clock in the ie in solution.Water vapour is by the recyclable utilization of condenser.
Weight percent concentration is too low owing to concentration less than 2% NMMO waste liquid, can carry out concentration before reduction vaporization, and being concentrated into weight percent concentration is 4～6%.
The invention has the beneficial effects as follows: the inventive method and domestic existing method for recovering solvents are relatively; the rate of recovery of NMMO waste liquid brings up to 99.5% by 95%; reclaim NMMO concentration reduction in the waste water of discharging the back; save steam; greatly reduce the production cost of fiber, help environmental protection and energy savings consumption.
The specific embodiment
The present invention adopts the method for a plurality of ion exchange resin exchange columns and multiple-effect evaporation that the NMMO in the NMMO waste liquid is reclaimed.
The recovery method of NMMO waste liquid comprises following step:
1, the NMMO waste liquid that will contain variable concentrations mixes through blender, and removes solid impurity with mechanical filter;
2, the liquid after step 1 filtration is squeezed into cation exchange resin column to remove metal ion with flow 3～6BV/h;
3, step 2 being removed liquid behind the metal ion squeezes into the resin anion (R.A.) exchange column with flow 3～6BV/h and removes coloring matter and catabolite;
4, the solution that step 3 is obtained is squeezed into triple effect evaporator and is carried out reduction vaporization, and one imitates heating and temperature control at 82～86 ℃, and evaporating temperature is controlled at 70～74 ℃; Two imitate heating and temperature control at 70～74 ℃, and evaporating temperature is controlled at 58～62 ℃; The triple effect heating and temperature control is at 58～62 ℃, and evaporating temperature is controlled at 46～50 ℃, when solution concentration to refractive index of liquid reached for 1.480 (containing NMMO concentration 86.6%), stops evaporation; Water vapour is recycled by condenser;
5, step 4 gained concentrated liquid is put into container, treat that it cools off naturally, after the crystallization, promptly make the NMMO that contains a crystallization water.
Resin cation is macroporous type or gel-type highly acid polystyrene cationic ion-exchange resin.
Resin anion (R.A.) is macroporous type or gel-type alkalescent acrylic acid series resin anion (R.A.).
When NMMO waste liquid weight percent concentration (down with) less than 2% the time, before reduction vaporization, can carry out concentration, being concentrated into concentration is 4～6%.
When the NMMO liquid waste concentration is 8～28%, can further remove impurity, flow rate of mobile phase 3～6BV/h by the exchange column that resin cation and resin anion (R.A.) mix before the reduction vaporization.
The invention will be further elaborated below in conjunction with embodiment.Embodiment only is used to illustrate the present invention, rather than limits the present invention by any way.
Embodiment one
The recycling of the NMMO waste liquid of collecting from coagulating tank, drawing-off groove may further comprise the steps:
1, the NMMO waste liquid a (concentration 25% that reclaims from coagulating tank, drawing-off groove, 811 kilograms of weight) and waste liquid b (concentration 12%, 695 kilograms of weight) (mixed proportion of a, b waste liquid is 6～5: 4～5), mixed waste liquid c (concentration 19%) sends into head tank by the blender mixing.
2, waste liquid c removes solid impurity through mechanical filter and enters the clear liquid storage tank.
3, the liquid after will filtering with the flow of 3.2BV/h squeeze into cation exchange resin column with remove metal ion and will handle after liquid put into the clear liquid storage tank.
4, will remove behind the metal ion liquid with the 3.2BV/h flow squeeze into the resin anion (R.A.) exchange column remove coloring matter and catabolite and will handle after liquid put into the clear liquid storage tank.
5, liquid in the step 4 clear liquid storage tank is squeezed into the exchange column of resin cation and resin anion (R.A.) mixing with the 3.2BV/h flow, and the liquid after will handling is put into the clear liquid storage tank.
6, solution in the step 5 clear liquid storage tank being squeezed into triple effect evaporator with the backward feed flow process carries out reduction vaporization (one imitates heating and temperature control at 80 ℃, and evaporating temperature is controlled at 70 ℃; Two imitate heating and temperature control at 70 ℃, and evaporating temperature is controlled at 58 ℃; The triple effect heating and temperature control is at 58 ℃, and evaporating temperature is controlled at 46 ℃), so that the water in the clear liquid is evaporated, water vapour is recycled by condenser; When solution concentration when the refractive index of liquid of emitting reaches 1.480, stop evaporation.
7, the concentrated liquid after step 6 evaporation is put into container, treat that it cools off naturally, after the crystallization, promptly make the NMMO (322.8 kilograms of weight, the rate of recovery 99.50%) that contains a crystallization water.
Embodiment two
The recycling of the NMMO waste liquid that reclaims from sink may further comprise the steps:
1, waste liquid a that contains NMMO (concentration 0.05%, 645.8 kilograms of weight) and the waste liquid b (concentration 1.86%, 872.2 kilograms of weight) that comes from each sink mixes through blender, and mixing back NMMO waste liquid c concentration is 0.82%.
2, waste liquid c enters head tank after mechanical filter is removed solid impurity.
3, the solvent after will filtering squeeze into cation exchange resin column with the flow of 3.6BV/h and will receive solution put into the clear liquid storage tank.
4, with the liquid in the step 3 clear liquid storage tank with the 3.6BV/h flow squeeze into the resin anion (R.A.) exchange column and will receive liquid put into the clear liquid storage tank.
5, the liquid in the step 4 clear liquid storage tank is squeezed into the reverse-osmosis treated groove and carry out concentration, being concentrated into concentration is 5.2%.
6, the solution after step 5 is handled is squeezed into triple effect evaporator and is carried out reduction vaporization (one imitates heating and temperature control at 84 ℃, and evaporating temperature is controlled at 72 ℃; Two imitate heating and temperature control at 72 ℃, and evaporating temperature is controlled at 60 ℃; The triple effect heating and temperature control is at 60 ℃, and evaporating temperature is controlled at 48 ℃), when solution concentration when the refractive index of liquid of emitting reaches 1.480, stop evaporation;
7, concentrated liquid is put into container, treat that it cools off naturally, after the crystallization, promptly make the NMMO (14.04 kilograms of weight, the rate of recovery 99.52%) that contains a crystallization water.
Claims (4)
1. the recovery method of NMMO during solvent method fiber is produced is characterized in that: reduction vaporization was to index of refraction 1.480 after the NMMO waste liquid passed through cation exchange resin column, resin anion (R.A.) exchange column successively, and cooling promptly makes the NMMO that contains a crystallization water; Described reduction vaporization process adopts triple effect evaporator, and one imitates heating and temperature control at 78～82 ℃, and evaporating temperature is controlled at 68～72 ℃; Two imitate heating and temperature control at 68～72 ℃, and evaporating temperature is controlled at 56～60 ℃; The triple effect heating and temperature control is at 56～60 ℃, and evaporating temperature is controlled at 44～48 ℃.
2. the recovery method of NMMO during solvent method fiber according to claim 1 is produced, it is characterized in that: NMMO waste liquid weight percent concentration is 8～28% o'clock, the NMMO waste liquid is successively by behind cation exchange resin column, the resin anion (R.A.) exchange column, again by reduction vaporization behind the exchange column of resin cation and resin anion (R.A.) mixing.
3. the recovery method of NMMO during solvent method fiber according to claim 2 is produced is characterized in that: the flow rate of mobile phase 3～6BV/h of the exchange column that resin cation and resin anion (R.A.) mix.
4. the recovery method of NMMO is characterized in that: cation exchange resin column flow rate of mobile phase 3～6BV/h during solvent method fiber according to claim 1 was produced; Resin anion (R.A.) exchange column flow rate of mobile phase 3～6BV/h.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN2008103017545A CN101280476B (en) | 2008-05-23 | 2008-05-23 | Method for recovering NMMO solvent in solvent method fiber production |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2008103017545A CN101280476B (en) | 2008-05-23 | 2008-05-23 | Method for recovering NMMO solvent in solvent method fiber production |
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| CN101280476A CN101280476A (en) | 2008-10-08 |
| CN101280476B true CN101280476B (en) | 2010-04-14 |
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| CN2008103017545A Active CN101280476B (en) | 2008-05-23 | 2008-05-23 | Method for recovering NMMO solvent in solvent method fiber production |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| AT521561A5 (en) * | 2016-07-22 | 2022-09-15 | China Textile Academy | Process for the production of cellulose fibers |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN102341413B (en) | 2009-03-09 | 2014-09-17 | 柯兰姆有限公司 | Shaped cellulose manufacturing process combined with pulp mill recovery system |
| CN101942713B (en) * | 2009-07-07 | 2012-07-04 | 中国科学院化学研究所 | Recovery method of N-methylmorpholine oxide solvent in process of generating regenerated protein fibre by solvent method |
| CN102234852B (en) * | 2010-04-21 | 2013-04-10 | 聚隆纤维股份有限公司 | Solvent recovery method of Lyocell fiber |
| CN102167465A (en) * | 2011-03-17 | 2011-08-31 | 天津工业大学 | Recovery method of spinning waste liquor by means of concentrating |
| TW201240721A (en) * | 2011-04-01 | 2012-10-16 | Acelon Chem & Fiber Corp | Energy-efficient N-methylmorpholine-N-oxide solvent recycling method |
| CN102758273B (en) * | 2011-04-28 | 2014-05-14 | 聚隆纤维股份有限公司 | High-efficiency and energy-saving N-methylmorpholine-N-oxide solvent recovery method |
| US8932471B2 (en) | 2011-09-09 | 2015-01-13 | Acelon Chemicals & Fiber Corporation | Method of recovering and concentrating an aqueous N-methylmorpholine-N-oxide (NMMO) solution |
| CN103046167B (en) * | 2012-11-28 | 2014-12-24 | 上海聚友化工有限公司 | Evaporation and dehydration method for N-methylmorpholine-N-oxide solvent in cellulosic fiber production through solvent method |
| CN103541045A (en) * | 2013-10-30 | 2014-01-29 | 苏州龙杰特种纤维股份有限公司 | Method for recycling cooling water from production department |
| CN104711706B (en) * | 2015-03-17 | 2016-10-05 | 中国纺织科学研究院 | Recovery device and recovery method of Lyocell fiber spinning dope waste |
| CN109046475A (en) * | 2018-08-31 | 2018-12-21 | 山东英利实业有限公司 | The resource recycle method of N-methyl morpholine oxide in a kind of Lyocell fibers production process |
| CN109183199A (en) * | 2018-11-22 | 2019-01-11 | 淮安天然丝纺织科技有限公司 | A kind of NMMO solvent recovery method for concentration |
| DE102019116736B4 (en) * | 2019-06-20 | 2022-03-24 | List Technology Ag | Production process and apparatus for producing a dope from recycled fibers using the solvent process |
| CN115557917B (en) * | 2021-07-02 | 2024-04-19 | 华茂伟业绿色科技股份有限公司 | Purification method and system of N-methylmorpholine-N-oxide and obtained N-methylmorpholine-N-oxide |
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Cited By (2)
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| AT521561A5 (en) * | 2016-07-22 | 2022-09-15 | China Textile Academy | Process for the production of cellulose fibers |
| AT521561B1 (en) * | 2016-07-22 | 2023-02-15 | China Textile Academy | Process for the production of cellulose fibers |
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