EP0012960A1 - Procédé et appareil pour la cuisson en continu de matière fibreuse végétale - Google Patents

Procédé et appareil pour la cuisson en continu de matière fibreuse végétale Download PDF

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Publication number
EP0012960A1
EP0012960A1 EP79105195A EP79105195A EP0012960A1 EP 0012960 A1 EP0012960 A1 EP 0012960A1 EP 79105195 A EP79105195 A EP 79105195A EP 79105195 A EP79105195 A EP 79105195A EP 0012960 A1 EP0012960 A1 EP 0012960A1
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EP
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Prior art keywords
reactor
fiber material
organic solvent
plant fiber
extraction liquid
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Application number
EP79105195A
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German (de)
English (en)
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EP0012960B1 (fr
Inventor
Manfred Dr. Baumeister
Eugen Edel
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Md-Organocell Gesellschaft fur Zellstoff- und Umw
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MD Papier GmbH and Co KG
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Application filed by MD Papier GmbH and Co KG filed Critical MD Papier GmbH and Co KG
Priority to AT79105195T priority Critical patent/ATE1914T1/de
Publication of EP0012960A1 publication Critical patent/EP0012960A1/fr
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Publication of EP0012960B1 publication Critical patent/EP0012960B1/fr
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    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
    • D21C3/00—Pulping cellulose-containing materials
    • D21C3/20—Pulping cellulose-containing materials with organic solvents or in solvent environment

Definitions

  • the invention relates to a method and a device for the continuous digestion of plant fiber material with organic solvent.
  • DE-OS 2 637 449 describes a solvent extraction process for the production of cellulose pulp, in which lignin is extracted from finely divided fibrous plant material at elevated temperature and pressure with an aqueous solution of a lower aliphatic alcohol.
  • This method works with a plurality of extractors working in batches, with a series of work stages following one another in each extractor.
  • This known method is not suitable for the continuous, economical production of cellulose from plant fiber material.
  • the investment costs are disproportionately high due to the large number of extractors required.
  • the heating-up time per batch if not disproportionately large amounts of solvent are used very long so that hydrolytic degradation reactions of the cellulose and hemicellulose take place before the high temperature required for the dissolution of the lignin is reached. Therefore, it is not possible with the known method to obtain pulp for paper production with sufficient strength.
  • the invention has for its object a method and an apparatus for continuous digestion
  • the essential components of the vegetable fiber material namely lignin, hemicellulose and cellulose can be separated and obtained in pure form, which works economically on an industrial scale, which is characterized by a simple process, in particular those described above Disadvantages of the known methods are avoided, and that provides a high quality and easily bleachable cellulose.
  • the invention relates to a process for the continuous digestion of plant fiber material, in which the plant fiber material is treated in countercurrent at temperatures of 130 to 210 ° C with organic solvent, which is characterized in that the plant material is impregnated with organic solvent in an impregnation device impregnated plant fiber material is introduced into the head of a reactor by means of an introduction device and is forcibly guided downwards through it, cellulose is applied to the bottom of the reactor, organic solvent with a temperature of between 130 and 210 ° C.
  • the invention further relates to a device for the continuous digestion of plant fiber material with organic solvent, which comprises an impregnator, a reactor for disintegrating the plant fiber material, washing devices for the digested plant fiber material and separating devices, which is characterized in that the impregnator in which the plant fiber material is impregnated with organic solvent is designed as a screw conveyor and directly via a Pressure lock with the head of the reactor is connected, that in the reactor integrally a cooking zone and a washing zone are provided, the reactor at the bottom one or more inlets for the washing liquid and an outlet for the digested vegetable fiber material, in the middle area a discharge for the washing liquid and one or more feeds for the extraction liquid and, in the reactor head, an introduction device for the plant fiber material and furthermore a draw-off for the loaded extraction liquid, and separation devices for the separation of lignin, hemicellulose and solvents are provided.
  • the impregnator in which the plant fiber material is impregnated with organic solvent is designed as a screw conveyor and directly via
  • the advantages of the process according to the invention are, in particular, that economical operating sizes can be achieved with only 50 to 100 tonnes per day, that the raw materials contained in the raw material, namely hemicellulose and lignin, are largely obtained in native form, and that the organic solvents used for the extraction are obtained can be recovered and reused for example by simple distillation and subsequent condensation.
  • the process can be used for all pumpable, pourable and free-flowing cellulose-containing raw materials.
  • wood from indigenous and tropical provinces and annual plants such as straw and bagasse are suitable as raw materials.
  • the cellulose obtained by the process according to the invention is excellently suitable for paper production due to its high quality.
  • the other essential constituents of the plant fiber material can be obtained in native, pure form, so that these products are available for further processing in various areas.
  • the method according to the invention now allows for the first time to obtain the further essential constituents, namely lignin and hemicelluloses, in the form of pure, valuable raw materials.
  • the hemicelluloses are suitable for a variety of uses, their use being particularly noteworthy in the following areas: Production of sugars, in particular sorbitol and mannitol: Production of thickeners, adhesives, size and thickeners for the Paper, textile and coatings industry; Further processing to alcohol by fermentation. It should be emphasized that it can be advantageous to reuse the alcohol obtained from the hemicelluloses as a solvent in the process according to the invention.
  • lignin can be obtained in native and largely pure form.
  • Lignin is an extremely valuable raw material. It is obtained as a polyol in the process and is particularly suitable for the production of synthetic resins. A reaction with aldehydes is particularly suitable.
  • synthetic resins that can be obtained starting from lignin particular mention should be made of polyurethanes, acetal resins, epoxy resins and phenolic resins.
  • Organic solvents are used as the extraction liquid.
  • the organic solvents should preferably be miscible with water in any ratio.
  • Particularly suitable are aliphatic alcohols with 1 to 6 carbon atoms, including polyhydric alcohols, such as glycol and glycerol, aromatic and aliphatic amines, ketones, such as acetone and methyl ethyl ketone, ethers, such as tetrahydrofuran and dioxane, and solvents, such as dimethylformamide and dimethyl sulfoxide.
  • Aliphatic alcohols, in particular ethyl alcohol and isopropyl alcohol are preferably used as solvents.
  • the solvents can be used in pure form or as mixtures with water. In the case of aqueous mixtures, concentrations of the solvent in the water of 10 to 100%, preferably between 40 and 60%, are suitable.
  • the impregnation can be carried out at atmospheric pressure, which is preferred, or at overpressure. It can be carried out at room temperature or at an elevated temperature, a temperature between 40 and 80 ° C., in particular about 60 ° C., being preferred.
  • extraction is preferably carried out at temperatures between 130 and 210 ° C., in particular between 180 and 200 ° C.
  • the pressure in the reactor is between 1 and 40 bar, preferably between 15 and 25 bar.
  • the extraction liquid leaving the reactor which is loaded with the substances extracted from the plant fiber material, is broken down into its constituent parts, i.e. essentially lignin, hemicellulose and solvent, separated.
  • the solvent preferably the alcohol
  • the solvent can be removed in a simple manner by distillation, stripping or flashing.
  • the remaining aqueous phase which contains lignin and hemicellulose, can be separated into its constituents, for example, in that the concentration shift by the ent Removal of the alcohol and by lowering the temperature, the lignin is precipitated and this is isolated in a suitable manner, for example by means of a screw press, centrifuge or a heavy phase separator.
  • the remaining hemicelluloses can then turn a eindarwolf R and processing are supplied.
  • the impregnation of the plant fiber material which is usually in the form of wood chips, is important.
  • the impregnation can be carried out in a simple manner in the present process.
  • impregnation essentially fulfills the following functions.
  • Non-condensable gases and terpenes are expelled from the wood chips, so that there is no influence on the heat transfer and the diffusion of the cooking chemicals into the wood chips.
  • the wood chips adsorb condensate vapor, increasing the density at the same time.
  • the moisture displaces air from the wood chip surface.
  • the wood chips are introduced into a so-called steaming container via a metering device.
  • the wood chips are treated with saturated steam at pressures of 1 to 3 bar. Steam pretreatment is done for the reasons mentioned above.
  • the steam-heated chips are then transported to an impregnation tank. This is where the actual impregnation with cooking liquor begins.
  • the wood chips saturated with cooking liquor are then hydraulically pumped out of the impregnation tank by means of a high-pressure conveying device into an inclined separation tube at the head of the reactor.
  • the wood chips are transported into the reactor head by means of a screw conveyor.
  • the excess impregnation liquor is returned to the impregnation tank via a cylindrical sieve located in the separation tube.
  • the organic solvent removes the terpenes and resins that interfere with the penetration of the digestion liquid. For this reason, the use of a damping device operated under positive pressure can be dispensed with entirely. It goes without saying that the method according to the invention can nevertheless be used to dampen the wood chips.
  • the entire impregnation device can be reduced to an inclined impregnation tube located at the head of the reactor.
  • the wood chips are pushed upwards by means of a screw in the riser pipe filled with extraction liquid.
  • the residence time of the wood chips in the impregnation zone is, for example, between 1 and 15 minutes, preferably 2 to 5 minutes, depending on the throughput.
  • the wood chips are then sufficiently impregnated with extraction liquid to ensure immediate immersion in the cooking zone.
  • the pressure-free impregnation with the organic solvent ensures an even concentration distribution of the solution achieved in the raw material and thus a defined starting point for the extraction stage.
  • the chips are introduced against the high pressure prevailing in the extraction vessel preferably by means of a pressure lock controlled in time. It is advantageous to apply pressure to the pressure lock, preferably by means of steam, in order to keep the pressure difference between the pressure lock and the reactor low and thereby avoid pressure fluctuations in the reactor. If the pre-impregnation is carried out without pressure and the reactor operates at 18 bar, it is advantageous, for example, to introduce steam at 16 bar into the pressure lock.
  • the impregnated wood chips can then be easily pressed under the liquid level in the extraction reactor using an insertion device, preferably a screw.
  • the introduction device also causes the wood chips to be forcibly conveyed through the reactor. Due to the pre-impregnation and the forced conveyance, there is certainly no formation of wood chip bridges at the entry point and thus a blockage of the material flow.
  • the cooker can be divided into four reaction zones.
  • the first zone is an impregnation zone.
  • an impregnation zone is necessary despite the pre-impregnation in order to achieve perfect saturation of the wood chips with cooking chemicals the chips are brought to the desired cooking temperature.
  • the cooking zone in which the actual lignin degradation takes place.
  • a J washing and cooling zone in which the dissolved decomposition components are removed by countercurrent extraction with hot water. The washing water is used as the Q uench- liquid to stop the degradation reaction.
  • the reactor comprises only two zones, namely a cooking zone and a washing zone.
  • the wood chips are introduced into the cooking liquid at the top of the reactor, working at extraction liquid temperatures between 130 and 210 ° C. Cooking takes place in countercurrent, the delignification of the chips starting practically immediately upon contact with the hot extraction liquid. To achieve sufficient delignification rates, it is necessary to reach a sufficiently high temperature of the wood chips as quickly as possible. Lignin degradation by means of organic solvents or solvent / water mixtures is essentially a thermal radical degradation and only achieves a rate that is sufficient for practical use at higher temperatures. However, since the lignin condensation and thus insolubilization begins at low temperatures, a heating-up period that is too long means that the lignin is only incompletely extracted - can be. The necessary rapid heating of the wood chips takes place in the method according to the invention due to the guidance of the impregnated wood chips in countercurrent to the hot extraction liquid.
  • the fresh extraction liquid is preferably fed in from the periphery of the reactor through a ring line.
  • extraction liquid can be fed in the middle of the reactor, for example via a hollow shaft.
  • the extraction liquid which rises in countercurrent to the wood chips, is drawn off at the top of the reactor.
  • the organic solvent is recovered by distillation and condensation and recycled.
  • washing liquid which heats up in contact with the wood chips migrating downward.
  • the feed is preferably carried out via a peripheral ring line and / or a hollow shaft arranged in the reactor axis. Due to the high rate of diffusion of organic solvents, the solvent is practically completely removed from the largely delignified material during countercurrent washing of the wood chips. In the middle of the reactor, the washing liquid loaded with solvent and degradation products is generally drawn off together with part of the hot cooking liquid.
  • the removed washing liquid is preferably solvent, for example by means of a metering pump added in such an amount that the desired composition of the extraction liquid is reached again:
  • the extraction liquid is then brought to the required temperature, for example via a heat exchanger, and fed in via a peripheral ring line and / or a hollow shaft in the middle of the reactor.
  • washing liquid is not used for quenching the reaction, but rather is a component of the extraction liquid fed into the reactor.
  • Fluctuations in the process and the raw material, which cause changes in the composition of the extraction liquid, can be easily compensated for in the method according to the invention.
  • the chips are washed in countercurrent with pure water at a relatively high temperature. Because of the low concentration of wash water in organic solvent, the wash is much more effective than a wash using pure extractant as the washing liquid.
  • the digested material is usually discharged through a blow tank, washed again if necessary, and then sorted and processed in the usual way,
  • the invention is based on the drawing naner
  • the single figure shows a flow diagram of the impregnation, extraction, washing and separation stage of the process according to the invention.
  • the plant fiber material for example wood chips
  • the impregnator 1 which operates at atmospheric pressure and at a temperature of 60 ° C., via the insertion device 16.
  • An ethanol-water mixture is fed to the impregnator via line 17.
  • the impregnated wood chips are conveyed upwards by means of the screw conveyor 18 through the inclined impregnator and fed to a pressure lock 2 via a discharge device 19.
  • the pressurized wood chips are then introduced into the reactor 3 above.
  • the chips are pressed below the liquid level by the vertically arranged screw 20 and passed down through the reactor. On their way through the reactor, the chips are first flowed through in countercurrent by the Tisser extraction liquid, the dissolving lignin and other cellulose companions being drawn out of the chips by diffusion and being carried away by the upstream extraction liquid.
  • the extraction liquid enriched with extract leaves the reactor via line 10.
  • the extraction liquid is then fed via a cooler 23, to a waste-gas relaxation vessel 24.
  • the solvent vapors released are condensed in a vapor condenser 25 and the solvent is recirculated via line 33 to the process.
  • the remaining aqueous solution of hemicelluloses and lignin is fed to a screw press 28 by a pump 26 via a further cooler 27.
  • a centrifuge or a heavy phase separator can replace the screw press.
  • the lignin precipitates in the screw press and is separated from the hemicelluloses.
  • the hemicelluloses and the lignin, which are drawn off via lines 29 and 30, can then be sent separately for further processing.
  • Fresh solvent is fed to the process via line 34.
  • the washed-out pulp is withdrawn from the reactor at the end of the washing zone 5 via outlet 7. Washing liquid in the form of water is fed to the reactor on the reactor floor via the peripheral ring line 32 and / or the hollow shaft 6.
  • cellulose of excellent quality and bleachability are obtained, which are ideally suited as a raw material for papermaking.
  • Hemicelluloses and lignin are obtained in pure form and can be used in many different ways as valuable raw materials.

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  • Paper (AREA)
  • Extraction Or Liquid Replacement (AREA)
  • Packging For Living Organisms, Food Or Medicinal Products That Are Sensitive To Environmental Conditiond (AREA)
  • Formation And Processing Of Food Products (AREA)
  • General Preparation And Processing Of Foods (AREA)
EP79105195A 1978-12-20 1979-12-14 Procédé et appareil pour la cuisson en continu de matière fibreuse végétale Expired EP0012960B1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT79105195T ATE1914T1 (de) 1978-12-20 1979-12-14 Verfahren und vorrichtung zum kontinuierlichen aufschliessen von pflanzenfasermaterial.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE2855052 1978-12-20
DE19782855052 DE2855052A1 (de) 1978-12-20 1978-12-20 Verfahren und vorrichtung zum kontinuierlichen aufschliessen von pflanzenfasermaterial

Publications (2)

Publication Number Publication Date
EP0012960A1 true EP0012960A1 (fr) 1980-07-09
EP0012960B1 EP0012960B1 (fr) 1982-12-01

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ID=6057775

Family Applications (1)

Application Number Title Priority Date Filing Date
EP79105195A Expired EP0012960B1 (fr) 1978-12-20 1979-12-14 Procédé et appareil pour la cuisson en continu de matière fibreuse végétale

Country Status (7)

Country Link
EP (1) EP0012960B1 (fr)
AT (1) ATE1914T1 (fr)
BR (1) BR7908189A (fr)
CA (1) CA1111694A (fr)
DE (2) DE2855052A1 (fr)
FI (1) FI69130C (fr)
PL (1) PL220500A1 (fr)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3227843A1 (de) * 1981-08-06 1983-02-24 Chemiefaser Lenzing AG, 4860 Lenzing, Oberösterreich Verfahren zur herstellung von zellstoffen mit niedrigem ligningehalt
DE3240725A1 (de) * 1981-11-12 1983-05-19 Chemiefaser Lenzing AG, 4860 Lenzing, Oberösterreich Verfahren zur aufarbeitung von gebrauchter aufschlussfluessigkeit sowie anlagen zur durchfuehrung dieses verfahrens
EP0090969A1 (fr) * 1982-04-06 1983-10-12 MD-Organocell Gesellschaft für Zellstoff- und Umwelttechnik mbH Procédé et réacteur pour la cuisson continue d'une matière fibreuse végétale
EP0224470A1 (fr) * 1985-11-29 1987-06-03 Neusiedler Aktiengesellschaft für Papierfabrikation Procédé de production de pâte cellulosique à partir de matière fibreuse végétale
EP0498330A1 (fr) * 1991-02-06 1992-08-12 Organocell Gesellschaft für Zellstoff- und Umwelttechnik mbH Procédé pour la délignification d'une matière fibreuse végétale
WO1999014424A1 (fr) * 1997-09-15 1999-03-25 MELVILLE, Gordon, Brown Procede et appareil de fabrication de pate

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3339449A1 (de) * 1983-10-31 1985-05-09 MD Verwaltungsgesellschaft Nicolaus GmbH & Co. KG, 8000 München Verfahren zur gewinnung von lignin aus alkalischen lignin-loesungen
US5788812A (en) * 1985-11-05 1998-08-04 Agar; Richard C. Method of recovering furfural from organic pulping liquor
MY137982A (en) * 1999-08-11 2009-04-30 Startech Internat Group Ltd Integrated process for treating oil palm biomass wastes
DE102009051884A1 (de) * 2009-11-04 2011-05-05 Blue Globe Energy Gmbh Bioraffinerie-Verfahren

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3585104A (en) * 1968-07-29 1971-06-15 Theodor N Kleinert Organosolv pulping and recovery process

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE532741C (de) * 1929-11-02 1931-09-08 Kurt Von Tayenthal Dr Ing Verfahren zum Aufschluss von Pflanzenfaserstoffen
GB945957A (en) * 1960-02-08 1964-01-08 Ass Pulp & Paper Mills Continuous pulping process
DE2644155C2 (de) * 1976-09-30 1978-07-27 Theodor N. Dr. Pointe Claire Quebec Kleinert (Kanada) Kontinuierliches Aufschluß- und Ruckgewinnungsverfahren für pflanzliche Faserrohstoffe zur Herstellung von Zellstoff im organischen Lösungsmittel
CA1131415A (fr) * 1978-11-27 1982-09-14 Bau- Und Forschungsgesellschaft Thermoform A.G. Transformation en pate de la lignocellulose avec un melange aqueux d'un catalyseur et du methanol

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3585104A (en) * 1968-07-29 1971-06-15 Theodor N Kleinert Organosolv pulping and recovery process

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
K.W. BRITT: "Handbook of Pulp and Paper Technology", zweite Auflage, 1970, van Nostrand Reinhold Company, Seiten 145-158 New York, U.S.A. G. ROWLANDSON: "Continuous Digester" * Seiten 145, 146, 148-158 * *

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3227843A1 (de) * 1981-08-06 1983-02-24 Chemiefaser Lenzing AG, 4860 Lenzing, Oberösterreich Verfahren zur herstellung von zellstoffen mit niedrigem ligningehalt
DE3240725A1 (de) * 1981-11-12 1983-05-19 Chemiefaser Lenzing AG, 4860 Lenzing, Oberösterreich Verfahren zur aufarbeitung von gebrauchter aufschlussfluessigkeit sowie anlagen zur durchfuehrung dieses verfahrens
EP0090969A1 (fr) * 1982-04-06 1983-10-12 MD-Organocell Gesellschaft für Zellstoff- und Umwelttechnik mbH Procédé et réacteur pour la cuisson continue d'une matière fibreuse végétale
EP0224470A1 (fr) * 1985-11-29 1987-06-03 Neusiedler Aktiengesellschaft für Papierfabrikation Procédé de production de pâte cellulosique à partir de matière fibreuse végétale
EP0498330A1 (fr) * 1991-02-06 1992-08-12 Organocell Gesellschaft für Zellstoff- und Umwelttechnik mbH Procédé pour la délignification d'une matière fibreuse végétale
US5470433A (en) * 1991-02-06 1995-11-28 Brodersen; Karl-Heinz Process for the delignification of cellulose fiber raw materials using alcohol and alkali
WO1999014424A1 (fr) * 1997-09-15 1999-03-25 MELVILLE, Gordon, Brown Procede et appareil de fabrication de pate

Also Published As

Publication number Publication date
EP0012960B1 (fr) 1982-12-01
FI793985A (fi) 1980-06-21
CA1111694A (fr) 1981-11-03
DE2855052A1 (de) 1980-06-26
ATE1914T1 (de) 1982-12-15
PL220500A1 (fr) 1980-12-01
FI69130C (fi) 1985-12-10
DE2964181D1 (en) 1983-01-05
BR7908189A (pt) 1980-07-22
FI69130B (fi) 1985-08-30

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