CN107722126A - A kind of cellulose diacetate pilot test system - Google Patents
A kind of cellulose diacetate pilot test system Download PDFInfo
- Publication number
- CN107722126A CN107722126A CN201711066939.8A CN201711066939A CN107722126A CN 107722126 A CN107722126 A CN 107722126A CN 201711066939 A CN201711066939 A CN 201711066939A CN 107722126 A CN107722126 A CN 107722126A
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- washing
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- drying device
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08B—POLYSACCHARIDES; DERIVATIVES THEREOF
- C08B3/00—Preparation of cellulose esters of organic acids
- C08B3/06—Cellulose acetate, e.g. mono-acetate, di-acetate or tri-acetate
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08B—POLYSACCHARIDES; DERIVATIVES THEREOF
- C08B3/00—Preparation of cellulose esters of organic acids
- C08B3/22—Post-esterification treatments, including purification
- C08B3/26—Isolation of the cellulose ester
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- Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Biochemistry (AREA)
- Materials Engineering (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Polysaccharides And Polysaccharide Derivatives (AREA)
Abstract
A kind of cellulose diacetate pilot test system, including reactor and washing and drying device；Reactor is connected with coolant circuit, and the bottom of reactor is connected with steam pipework, and the top of reactor is connected with each raw material storage tank and wood pulp charge door；The bottom of reactor is connected with washing and drying device, the top of washing and drying device is connected with steam pipework and desalted water pipeline, water washing cycles pipeline is provided between the bottom of washing and drying device and the top of washing and drying device, the water washing cycles pipeline is connected with washing heat exchanger, and the bottom of washing and drying device is additionally provided with exhaust-valve；The top of reactor and washing and drying device is connected with vavuum pump respectively, and vavuum pump is connected with reacting replacing heat device.The system realizes carries out pilot scale to different types of dissolving pulp in cellulose diacetate production process on performance is acetified, and makes the technological parameter during final production controlled, directly carries out industrialized production, avoids result in the generation of waste product, solid dangerous waste thing occurs.
Description
Technical field
The present invention relates to a kind of pilot test system for cellulose acetate production, belongs to cellulose acetate technology of preparing neck
Domain.
Background technology
Cellulose diacetate (hereinafter referred to as vinegar sheet) is using high-purity bleached dissolving pulp as raw material, makees acetylation with aceticanhydride
Agent, acetic acid make solvent, and under catalyst sulfuric acid effect, acetylation is carried out to wood pulp cellulose, by hydrolysis, precipitating, washing, crowded
The process such as pressure, dry is produced.Specifically production process is：Wood pulp by crushing stirs in preprocessor together with acetic acid
Mix, be then fed into acetifier and carry out reaction generation Triafol T with nitration mixture；Reaction is passed through low-pressure steam after terminating, add one
Quantitative spirit of vinegar, the hydrolysis generation cellulose diacetate (vinegar sheet) under the conditions of existing for sulfuric acid；Again through precipitating, washing, extruding,
The process such as dry obtains product vinegar sheet.
Different types of dissolving pulp (hard wood pulp, soft wood pulp, cotton pulp) and the different producer of same kind of dissolving pulp exist
Acetify variant in performance, if directly carrying out industrialized production, uncontrollable parameters of technique process easily occur, cause to give up
The generation of product, substantial amounts of manpower, financial resources, material resources can be wasted, solid dangerous waste thing also occur if serious.Need the intermediate experiment stage
Further to study the changing rule of each step chemical reaction condition, and solve that laboratory lab scale cann't be solved or find asks
Topic, design data and amount of substance and consumption etc. are provided for formal production.
But at present, it can also carry out pilot scale to cellulose diacetate without one kind and make to acetify performance to dissolving pulp to comment
Valency and the system for determining final production technique.
The content of the invention
The present invention for existing cellulose diacetate life tea during dissolving pulp species it is various need carry out pilot scale and in
It is insufficient existing for examination technology, there is provided it is a kind of can thoroughly evaluating dissolving pulp acetify in the cellulose diacetate of performance and final products
Test system.
The cellulose diacetate pilot test system of the present invention, using following technical proposals：
The system, including reactor and washing and drying device；Agitator is provided with reactor, folder is provided with outside reactor
Set, chuck are connected by reacting cooling valve with coolant circuit, and the bottom of reactor passes through reaction vapor valve and steam pipework phase
Even, the top of reactor is connected by inlet valve with acetic acid tank, nitration mixture storage tank, magnesium acetate storage tank and diluted acid storage tank respectively；It is mixed
Chuck is provided with outside acid storage tank, the chuck cools down valve by nitration mixture and is connected with coolant circuit；Pass through wood at the top of reactor
Slurry inlet valve is connected with wood pulp charge door；
The bottom of reactor is connected by baiting valve with washing and drying device；The top of washing and drying device passes through water-washed vapor valve
It is connected with steam pipework, the top of washing and drying device is also connected by desalination water valve with desalted water pipeline, the bottom of washing and drying device
Water washing cycles pipeline is provided between portion and the top of washing and drying device, lower valve, acid are connected with turn on the water washing cycles pipeline
Wash water pump and upper valve, it is connected between pickling water pump and upper valve by tapping valve with washing heat exchanger, washing heat exchanger passes through waste liquid
Valve connection waste liquid is filled, and washing heat exchanger is connected with circulating water loop, and the bottom of washing and drying device is additionally provided with exhaust-valve.
The top of reactor and washing and drying device is connected by reacting vacuum valve and washing vacuum valve with vavuum pump respectively, very
Empty pump is connected with reacting replacing heat device, and reacting replacing heat device is connected with circulating water loop.
The process that said system carries out cellulose diacetate pilot scale is as described below：1. wood pulp is added in reactor, and
Acetic acid is added, is pre-processed；2. the reactor that the nitration mixture of cooling is discharged into after cooling, acetifies reaction；3. sequentially add acetic acid
Magnesium and spirit of vinegar；4. add magnesium acetate after being heated up in reactor；5. continuing to heat up, magnesium acetate is added, terminates hydrolysis；
6. the slurries in reactor are discharged into washing and drying device, wash and dry.
The present invention is realized in cellulose diacetate production process to different types of dissolving pulp to acetify performance enterprising
Row pilot scale, evaluation is made to acetify performance to dissolving pulp, the system for determining final production technique, makes the work during final production
Skill parameter is controlled, directly carries out industrialized production, avoids result in the generation of waste product, solid dangerous waste thing occurs.
Brief description of the drawings
Fig. 1 is the structural representation of cellulose diacetate pilot test system of the present invention.
In figure：1. reactor, 2. blanking devices, 3. washing and drying devices, 4. acetic acid tanks, 5. nitration mixture storage tanks, the storage of 6. magnesium acetates
Tank, 7. diluted acid storage tanks, 8. wood pulp charge doors, 9. vavuum pumps, 10. reacting replacing heat devices, 11. washing heat exchangers, 12. pickling water pumps,
13. waste liquid fills, 14. desalted water pipelines, 15. steam pipeworks, 16. coolant circuits, 17. exhaust-valves, 18. circulating water loops, and 19.
Nitration mixture cools down valve, 20. reaction cooling valves, 21. reaction vapor valves, 22. desalination water valves, 23. washing vacuum valves, 24. reaction vacuum
Valve, 25. baiting valves, 26. water-washed vapor valves, 27. upper valves, 28. lower valves, 29. tapping valves, 30. waist valves, 31. inlet valves, 32.
Agitator, 33. wood pulp inlet valves, 34. water washing cycles pipelines.
Embodiment
As shown in figure 1, the cellulose diacetate pilot test system of the present invention, including reactor 1 and washing and drying device 3.Reaction
Agitator 32 is provided with device 1.Reactor 1 is jacketed reactor, and chuck is provided with outside it, and chuck, which passes through, reacts cooling valve 20
It is connected with coolant circuit 16, refrigerated brine is circulated by coolant circuit 16 in chuck, makes to reach required temperature in reactor 1
Degree.The bottom of reactor 1 is connected by reaction vapor valve 21 with steam pipework 15.The top of reactor 1 is respectively by respective
Inlet valve 31 is connected with acetic acid tank 4, nitration mixture storage tank 5, magnesium acetate storage tank 6 and diluted acid storage tank 7.It is also provided with outside nitration mixture storage tank 5
There is chuck, the chuck cools down valve 19 by nitration mixture and is connected with coolant circuit 16, and refrigerated brine is being pressed from both sides by coolant circuit 16
Circulated in set, make to reach required temperature in nitration mixture storage tank 5.The top of reactor 1 is additionally provided with wood pulp charge door 8, wood pulp charging
Mouth 8 is connected by wood pulp inlet valve 33 with reactor 1.
The bottom of reactor 1 is connected by baiting valve 25 with blanking device 2, and blanking device 2 is connected with washing and drying device 3.Washing
The top of drier 3 is connected by water-washed vapor valve 26 with steam pipework 15.The top of washing and drying device 3 also passes through desalination water valve
It is connected with desalted water pipeline 14, to be washed to slurry.Between the bottom of washing and drying device 3 and the top of washing and drying device 3
Water washing cycles pipeline 34 is provided with, is connected with lower valve 28, pickling water pump 12 and upper valve 27 on the water washing cycles pipeline 34 in turn, acid
It is connected between wash water pump 12 and upper valve 27 by tapping valve 29 with washing heat exchanger 11, washing heat exchanger 11 is connected by waist valve 30
Connect waste liquid and fill 13.The effect one of pickling water pump 12 plays circulating pump when being vinegar sheet washing, second, discharge acid washing water.Washing is changed
Hot device 11 is connected with circulating water loop 18.Because washings contain acetic acid, if do not cool high temperature when volatilize too severe, live gas
Taste is pungent, so the acid washing water that washing and drying device 3 comes out is then exhausted from after washing heat exchanger 11 cools.Washing and drying device 3
Bottom is additionally provided with exhaust-valve 17.
The top of reactor 1 and washing and drying device 3 is respectively by reacting vacuum valve 24 and washing vacuum valve 23 and vavuum pump 9
It is connected.Vavuum pump 9 is connected with reacting replacing heat device 10, and reacting replacing heat device 10 is connected with circulating water loop 18.The effect one of vavuum pump 9
It is when 1 discharge of reactor, to vacuumizing for washing and drying device 3, accelerates blanking velocity；Second, taken out after steam heating vinegar sheet true
Sky, partial moisture in vinegar sheet is taken out of.Due to using more than 60 DEG C of hot water during washing vinegar sheet, acetic acid can be contained in steam, it is logical
Cross vavuum pump 9 to vacuumize, the steam containing acetic acid to condense recovery spirit of vinegar, while can be carried by reacting replacing heat device 10
The temperature of high washing desalted water.
Said system carries out the process of cellulose diacetate pilot scale, as described below：
(1) will be a certain amount of in the ratio (such as 5-10% of wood pulp weight) with wood pulp (hard wood pulp, soft wood pulp, cotton pulp) weight
Nitration mixture be added to nitration mixture storage tank 5, open nitration mixture freezing valve 19, the refrigerated brine in cooling system is passed through coolant circuit 16
Circulated in the chuck of nitration mixture storage tank 5, the nitration mixture temperature in nitration mixture storage tank 5 is dropped to 0-5 DEG C.
(2) start the agitating device of reactor 1, wood pulp will be passed through by the constant weight wood pulp (such as weight 5kg) crushed
Charge door 8 is added in reactor 1, and the inlet valve for opening acetic acid tank 4 adds the acetic acid (ratio as pressed wood pulp weight 0.5-3%
Example), pre-processed (such as 30-60 minutes).
(3) after pretreatment time reaches, reaction freezing valve 20 is opened, the refrigerated brine in cooling system is passed through coolant
Circulated in the chuck of reactor 1 in loop 16；The blow-off valve of nitration mixture storage tank 5 is opened again, and nitration mixture is discharged into reactor 1.
(4) by monitoring temperature rise rate and peak temperature in reactor 1, after reaching peak temperature, certain time is continued
Acetify reaction (such as 15-65 minutes).
(5) after acetifying complete reaction time arrival, the inlet valve for opening magnesium acetate storage tank 6 adds necessarily into reactor 1
20% magnesium acetate (such as 30-420g) of amount, continue stirring 5 minutes.
(6) inlet valve for opening diluted acid storage tank 7 adds dilute vinegar of a certain amount of (3-8kg) concentration 10% into reactor 1
Acid, stir 5 minutes.
(7) open steam and enter valve 21, by being passed through steam into reactor 1 with steam pipework 15, make within 25-50 minutes
Temperature is raised to 75 DEG C in reactor 1, adds a certain amount of (7.5-105g) 20% magnesium acetate.
(8) continue to heat up, 85 DEG C are raised in 10-20 minutes, be incubated 90-120 minutes, add a certain amount of (10-150g)
20% magnesium acetate, terminate hydrolysis.
Desalination water valve 22 is opened in hydrolytic process, desalted water is entered washing and drying device 3 by desalted water pipeline 14, is added
Liquid level of the desalted water to 60%.Start vavuum pump 9, first open the inlet valve (with air inlet blanking) of wood pulp charge door 8, then beat
Baiting valve 25 and washing vacuum valve 23 are opened, the slurries in reactor 1 is discharged into washing and drying device 3 by blanking device 2.Start vacuum
Pump 9, to vacuumizing for washing and drying device 3, blanking velocity can be accelerated.Desalted water is added by desalting pipe 14, opens acid washing water
Pump 12 and upper valve 27 and lower valve 28, tapping valve 29 is closed, make desalted water in 3 inner-outer circulation of washing and drying device 10 minutes, then
Upper valve 27 (lower valve 28 is opened) is closed, opens waist valve 30, the pickle for making to heat in washing and drying device 3 enters through pickling water pump 12
Enter to wash heat exchanger 11, pickle carries out heat exchange with recirculated water, and the pickle after condensation cooling is discharged in waste liquid tank 13.Repeat
Water-washing process 3-5 times.
(9) exhaust-valve 17 is opened, sour water can be discharged by exhaust-valve 17, there is one layer of filter screen, vinegar sheet in washing and drying device 3
Stay in washing and drying device 3.
(10) water-washed vapor valve 26 is opened, makes to be passed through steam in washing and drying device 3, dries 20-30 minutes.It is true to open washing
Empty valve 23, start vavuum pump 9, the steam after heating vinegar sheet is vacuumized, partial moisture in vinegar sheet taken out of, into reacting replacing heat
Device 10, carry out heat exchange.
(11) by the manhole on washing and drying device 3, dried vinegar sheet is taken out.
The process conditions in cellulose diacetate production process can be verified by said process.
Claims (1)
1. a kind of cellulose diacetate pilot test system, including reactor and washing and drying device；It is characterized in that：
Agitator is provided with reactor, chuck is provided with outside reactor, chuck is by reacting cooling valve and coolant circuit
It is connected, the bottom of reactor is connected by reaction vapor valve with steam pipework, and the top of reactor passes through inlet valve and vinegar respectively
Acid storage tank, nitration mixture storage tank, magnesium acetate storage tank connect with diluted acid storage tank；Chuck is provided with outside nitration mixture storage tank, the chuck passes through mixed
Acid cooling valve is connected with coolant circuit；The top of reactor is connected by wood pulp inlet valve with wood pulp charge door；
The bottom of reactor is connected by baiting valve with washing and drying device；The top of washing and drying device is by water-washed vapor valve with steaming
Vapor pipeline is connected, and the top of washing and drying device is also connected by desalination water valve with desalted water pipeline, the bottom of washing and drying device with
Water washing cycles pipeline is provided between the top of washing and drying device, lower valve, acid washing water are connected with turn on the water washing cycles pipeline
Pump and upper valve, it is connected between pickling water pump and upper valve by tapping valve with washing heat exchanger, washing heat exchanger is connected by waist valve
Waste liquid filling is connect, washing heat exchanger is connected with circulating water loop, and the bottom of washing and drying device is additionally provided with exhaust-valve.
The top of reactor and washing and drying device is connected by reacting vacuum valve and washing vacuum valve with vavuum pump respectively, vavuum pump
It is connected with reacting replacing heat device, reacting replacing heat device is connected with circulating water loop.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711066939.8A CN107722126A (en) | 2017-11-02 | 2017-11-02 | A kind of cellulose diacetate pilot test system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711066939.8A CN107722126A (en) | 2017-11-02 | 2017-11-02 | A kind of cellulose diacetate pilot test system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN107722126A true CN107722126A (en) | 2018-02-23 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201711066939.8A Pending CN107722126A (en) | 2017-11-02 | 2017-11-02 | A kind of cellulose diacetate pilot test system |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109503722A (en) * | 2018-11-01 | 2019-03-22 | 中峰化学有限公司 | A method of preparing cellulose acetate filament acetyl cellulose |
Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE1295809B (en) * | 1962-06-22 | 1969-05-22 | Jori | Method and device for diluting an acetic acid solution of cellulose acetate |
| AU5877773A (en) * | 1972-08-30 | 1974-09-26 | Awt Systems, Inc | Fluid bed dryer and heat exchange system |
| US4439605A (en) * | 1981-11-30 | 1984-03-27 | Daicel Chemical Industries, Ltd. | Process for producing cellulose acetate |
| JPS6417696A (en) * | 1987-07-14 | 1989-01-20 | Fuji Car Mfg | Dry cleaning machine |
| US20030223923A1 (en) * | 2002-06-03 | 2003-12-04 | Aspinwall Phil P. | Apparatus for production of cellulose acetate |
| JP2005052533A (en) * | 2003-08-07 | 2005-03-03 | Matsushita Electric Ind Co Ltd | Washing and drying machine |
| TW200612001A (en) * | 2002-06-26 | 2006-04-16 | Nihon Zaikei Kabushiki Kaisha | Apparatus for manufacturing cellulose acetate |
| CN101062956A (en) * | 2006-04-25 | 2007-10-31 | 株式会社Itef | Method of manufacturing cellulose acetate, high temperature steam reactor vessel used in the same method, and superheated steam generator used in the same method |
| CN203593714U (en) * | 2013-10-23 | 2014-05-14 | 浙江三和食品科技有限公司 | Device for preparing carboxy methyl cellulose by adopting three-step method |
| WO2017060928A1 (en) * | 2015-10-09 | 2017-04-13 | F.M.B. Fabbrica Macchine Bologna Spa | Washing and drying machine |
| WO2017061474A1 (en) * | 2015-10-08 | 2017-04-13 | 株式会社ダイセル | Cellulose acetate, and method and device for producing cellulose acetate |
| US20170265519A1 (en) * | 2014-11-28 | 2017-09-21 | Daicel Corporation | Cellulose acetate fiber tow band for use in cigarette filter, cigarette filter, apparatus for manufacturing tow band, and method of manufacturing tow band |
-
2017
- 2017-11-02 CN CN201711066939.8A patent/CN107722126A/en active Pending
Patent Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE1295809B (en) * | 1962-06-22 | 1969-05-22 | Jori | Method and device for diluting an acetic acid solution of cellulose acetate |
| AU5877773A (en) * | 1972-08-30 | 1974-09-26 | Awt Systems, Inc | Fluid bed dryer and heat exchange system |
| US4439605A (en) * | 1981-11-30 | 1984-03-27 | Daicel Chemical Industries, Ltd. | Process for producing cellulose acetate |
| JPS6417696A (en) * | 1987-07-14 | 1989-01-20 | Fuji Car Mfg | Dry cleaning machine |
| US20030223923A1 (en) * | 2002-06-03 | 2003-12-04 | Aspinwall Phil P. | Apparatus for production of cellulose acetate |
| TW200612001A (en) * | 2002-06-26 | 2006-04-16 | Nihon Zaikei Kabushiki Kaisha | Apparatus for manufacturing cellulose acetate |
| JP2005052533A (en) * | 2003-08-07 | 2005-03-03 | Matsushita Electric Ind Co Ltd | Washing and drying machine |
| CN101062956A (en) * | 2006-04-25 | 2007-10-31 | 株式会社Itef | Method of manufacturing cellulose acetate, high temperature steam reactor vessel used in the same method, and superheated steam generator used in the same method |
| CN203593714U (en) * | 2013-10-23 | 2014-05-14 | 浙江三和食品科技有限公司 | Device for preparing carboxy methyl cellulose by adopting three-step method |
| US20170265519A1 (en) * | 2014-11-28 | 2017-09-21 | Daicel Corporation | Cellulose acetate fiber tow band for use in cigarette filter, cigarette filter, apparatus for manufacturing tow band, and method of manufacturing tow band |
| WO2017061474A1 (en) * | 2015-10-08 | 2017-04-13 | 株式会社ダイセル | Cellulose acetate, and method and device for producing cellulose acetate |
| WO2017060928A1 (en) * | 2015-10-09 | 2017-04-13 | F.M.B. Fabbrica Macchine Bologna Spa | Washing and drying machine |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109503722A (en) * | 2018-11-01 | 2019-03-22 | 中峰化学有限公司 | A method of preparing cellulose acetate filament acetyl cellulose |
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