EP0813629A1 - Procede pour produire des pates a papier constituees de fibres courtes, a partir de bois de coniferes - Google Patents

Procede pour produire des pates a papier constituees de fibres courtes, a partir de bois de coniferes

Info

Publication number
EP0813629A1
EP0813629A1 EP96906140A EP96906140A EP0813629A1 EP 0813629 A1 EP0813629 A1 EP 0813629A1 EP 96906140 A EP96906140 A EP 96906140A EP 96906140 A EP96906140 A EP 96906140A EP 0813629 A1 EP0813629 A1 EP 0813629A1
Authority
EP
European Patent Office
Prior art keywords
activity
exocellulosic
enzyme preparation
pulp
process according
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP96906140A
Other languages
German (de)
English (en)
Inventor
Ulla-Britt Mohlin
Bert Pettersson
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.)
Svenska Traforskningsinstitutet
STFI Skogsindustrins Tekniska Forskningsinstitut AB
Original Assignee
Svenska Traforskningsinstitutet
STFI Skogsindustrins Tekniska Forskningsinstitut AB
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Svenska Traforskningsinstitutet, STFI Skogsindustrins Tekniska Forskningsinstitut AB filed Critical Svenska Traforskningsinstitutet
Publication of EP0813629A1 publication Critical patent/EP0813629A1/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • 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
    • D21C9/00—After-treatment of cellulose pulp, e.g. of wood pulp, or cotton linters ; Treatment of dilute or dewatered pulp or process improvement taking place after obtaining the raw cellulosic material and not provided for elsewhere
    • D21C9/001—Modification of pulp properties
    • 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
    • D21C5/00—Other processes for obtaining cellulose, e.g. cooking cotton linters ; Processes characterised by the choice of cellulose-containing starting materials
    • D21C5/005—Treatment of cellulose-containing material with microorganisms or enzymes

Definitions

  • the present invention relates to a process in accordance with the preamble of claim 1 for preparing chemical pulp.
  • the present invention also relates to an enzyme composition for said use.
  • Softwood pulp generally has the drawback of an unfavourable fibre length distribution. This negatively influences the formation and thus the printability and other properties of the paper and board, manufactured using said pulp.
  • Traditionally a portion of hardwood pulp is added to the softwood pulp to balance the fibre length distribution.
  • the use of thinning material or felling of young forests has also been contemplated, but this has sometimes unwanted effects on the total forest economy.
  • the use of enzymes is well known in the pulp and paper industry.
  • Xylanases are presently used as a pretreatment to facilitate bleaching.
  • Cellulases are also know to be used in the processing of recycled fibre to digest fines and improve dewatering on the paper machine.
  • WO 94/20667 describes an enzymatic process for pretreatment of wood raw- material which makes it possible to reduce the specific energy consumption of mechanical pulping and to improve the technical properties of the fibres.
  • the inventors describe a special enzyme preparation exhibiting simultaneously both celiobiohydrolase activity and mannanase activity. Thereby the hydrolysis of insoluble cellulose is avoided and the strength properties of the fibres not impaired. Again, fibre shortening would rather be a negative effect.
  • this process requires a cooler and more dilute pulp than what normally is the case in industrial pulp- and paper production. Additionally the long treatment times given in the examples suggest that very large storage volumes are necessary.
  • WO 92/18688 relates to a cellulase preparation with a high content of endogluca ⁇ nase and a little or no celiobiohydrolase for use for treatment of paper pulp, inter alia to improve the drainage properties of the pulp. It is obvious that such an enzyme treatment • mainly solubilizes the fines, thus improving the dewatering. It is noted, also in this description, that the damage to the cellulose fibres in the pulp is less, because of the low celiobiohydrolase activity.
  • the process and enzyme preparation according to the present invention can, of course, also be applied to unbleached chemical pulp but then the enzyme dosage and/or process conditions as treatment time, temperature and pH have to be adjusted accordingly.
  • the present description will deal only with the treatment of bleached softwood pulp.
  • the process and enzyme preparation according to the present invention when necessary, can be applied also to pulps including recycled fibres as well as virgin fibres and mixtures, in varying propor ⁇ tions, of the two. It has now surprisingly been shown that the simultaneous use of endo- and exocellulases in a treatment step before the beating operation results in a controlled fibre shortening in softwood pulp.
  • the fibres present in the chemical pulp are always to some extent mechanically damaged, i.e. the fibres show more or less sharp kinks and bends in their three dimensio- nal structure. It has now been shown that a combination of endo- and exocellulase activity, e.g. endo- and exoglucanase activity, attacks these damaged points and causes changes in the cellulose crystal structure. Thus, local weakening of the fibre is achieved. In other words the enzymatic treatment introduces local damage, in the following called "breakage domains" on the fibres. Later, when the pulp is subjected to mechanical action in the form of beating, using conventional equipment for this purpose, the fibres break in a controlled fashion at these breakage domains.
  • Figure 1 is a graphic representation showing zero-span tensile index as a function of enzymatic treatment at different enzyme dosages and temperatures
  • Figure 2 is a graphic representation showing the fibre length distribution of untreated pulp compared to the fibre length distribution of pulp subjected to enzymatic treatment according to the present invention.
  • the ratio of endocellulase activity to exo- cellulase activity can be varied.
  • Endoglucanase can be used together with a trace amount of exocellulase and vice versa, preferably in an interval of 1 : 100 to 100: 1.
  • the amount of exocellulase activity is significantly larger than the amount of endocellulase activity.
  • the ratio of exocellulase to endocellulase is in the interval of about 4: 1 to 5: 1 , which gives a synergistic effect.
  • An optimal ratio will depend on the actual enzymes used and their sources and this optimal ratio can easily be determined by a person skilled in the art.
  • the endocellulase is preferably endoglucanase and the exocellulase is preferably exoglucanase.
  • the endoglucanase and exoglucanase can be used in a clean, isolated form or as a mixture of enzymes from different sources. Also commercial enzyme mixtures exhibiting the above specified activities can be used.
  • Table 2 Examples of cellulase-producing bacteria ⁇ Cellulomonas flavigena, C. biazotea, C. cellasea, C. fimi, C. gelida, C. curtae,
  • fungi and bacteria listed above are only given as examples.
  • microorganisms of the species Trichoderma and Aspergillus are considered specially suitable for the production of the present enzymes but the scope of the present invention is not limited to the use of the named microorganisms. It is very possible that other enzyme producing microorganisms suitable for the present invention already exist or will be developed using mutation and selection or methods of genetical engineering. It is also likely, that the enzyme producing capabilities of an existing microorganism can be further enhanced through genetical engineering.
  • the environmental conditions during the enzymatic treatment are not critical for the scope of invention, but can of course be used to controll the enzymatic reaction.
  • the environmental conditions of the enzymatic treatment are to a certain extent governed by the normal process parameters of the pulping and paper making processes. Simultane ⁇ ously, the requirements of the enzyme or enzyme mixture have to be considered.
  • a pH in the interval of 2 - 13 is possible, while an interval of 4 - 10 is preferable, depending on the enzymes used.
  • the temperature of the reaction mixture is of considerable importance as it affects the reaction rate of the enzymes. The reaction rate directly influences the time needed for the desired reaction to take place and thus the necessary storage volumes.
  • the tempera ⁇ ture can be in an interval from about 5 - 95 °C, theoretically even higher e.g. about 100 °C, but preferably about 30 - 60 °C and most preferably about 45 - 50 °C.
  • highly thermotolerant enzymes which would enable the enzymatic treatment to be performed at considerably higher temperatures. It is possible that this would give rise to unexpected synergistic effects.
  • a skilled worker can, given the requirements of the enzymes in question, determine more exactly the optimum environmental conditions for application of the enzyme or enzyme mixture. The presence of heavy metals can also influence the en ⁇ zymatic activities and should therefore be avoided. A skilled worker with knowledge of both the manufacturing of paper and the usage of enzymes is able to adapt the process to accommodate the enzymatic treatment according to the present invention.
  • the enzymatic treatment is terminated before the pulp is subjected to the beating operation.
  • the enzymatic treatment is preferably terminated by adjusting the pH of the reaction mixture to an interval outside, preferably above, the functional interval of the enzyme mixture. This functional interval depends on the pH-stability of the enzyme, the temperature and other environmental conditions.
  • the beating operation is modified in relation to the enzymatic treatment.
  • enzymatically treated pulp requires a lower input of energy at the beating stage. It is of course of interest both to minimize the energy consumption and the production of fines during beating. A skilled worker can easily optimize the milling in relation to the enzymatic treatment.
  • the enzyme or enzyme mixture used is bound to a carrier in order to facilitate its removal and possible reuse. Suitable carriers and methods for immobilization of enzymes can be found in the littera- ture.
  • the present invention also relates to an enzyme composition for treatment of softwood pulp for the production of paper and board where essential product properties are obtained by controlling the fibre length distribution of the pulp, whereby said pulp is first subjected to enzymatic treatment and thereafter subjected to mechanical or equivalent actions in order to effectuate controlled fibre shortening at the breakage domains, characterized in that said enzyme preparation introduces local breakage domains on the fibres.
  • said enzyme preparation exhibits both endocellulosic and exocellulosic activity.
  • the ratio of endocellulosic activity to exocellulosic activity in said enzyme preparation is in the interval from 1: 100 to 100: 1. More preferably the exo- cellulosic activity is significantly larger than the endocellulosic activity and most prefe ⁇ rably the ratio of exocellulosic activity to endocellulosic activity is in the interval of about 4: 1 to 5: 1.
  • the exocellulosic activity is exoglucanase activity and the endocellulosic activity is endoglucanase activity.
  • ® enzyme mixture used was Celluclast from Novo Nordisk AS, Denmark, with an enzyme activity of 1500 NCU/g enzyme.
  • NCU One Novo Cellulase Unit (NCU) is the amount of enzym which, under standard conditions, degrades CMC to reducing carbohydrates with a reduction power corresponding to 1 ⁇ mol glucose per minute.
  • Pulp viscosity can be seen as a measure, relative to the average chain length for the cellulose.
  • shape factor on the other hand is the ratio of the projected length of the fiber and its real length, thus giving an indication of the curvature or crookedness of the fibre.

Landscapes

  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Wood Science & Technology (AREA)
  • Chemical & Material Sciences (AREA)
  • Biochemistry (AREA)
  • Microbiology (AREA)
  • Paper (AREA)

Abstract

L'invention concerne un procédé utilisant de la pâte à papier de conifères pour la production de papier et de carton dont les qualités essentielles comme par exemple une bonne qualité d'impression sont obtenues en modifiant la répartition des longueurs des fibres par un traitement enzymatique, suivi par un traitement mécanique des fibres, ou par un autre traitement équivalent.
EP96906140A 1995-03-09 1996-03-04 Procede pour produire des pates a papier constituees de fibres courtes, a partir de bois de coniferes Withdrawn EP0813629A1 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
SE9500846A SE506440C2 (sv) 1995-03-09 1995-03-09 Styrning av barrvedmassas fiberlängdsfördelning genom enzymatisk och mekanisk behandling
SE9500846 1995-03-09
PCT/SE1996/000284 WO1996028606A1 (fr) 1995-03-09 1996-03-04 Procede pour produire des pates a papier constituees de fibres courtes, a partir de bois de coniferes

Publications (1)

Publication Number Publication Date
EP0813629A1 true EP0813629A1 (fr) 1997-12-29

Family

ID=20397492

Family Applications (1)

Application Number Title Priority Date Filing Date
EP96906140A Withdrawn EP0813629A1 (fr) 1995-03-09 1996-03-04 Procede pour produire des pates a papier constituees de fibres courtes, a partir de bois de coniferes

Country Status (3)

Country Link
EP (1) EP0813629A1 (fr)
SE (1) SE506440C2 (fr)
WO (1) WO1996028606A1 (fr)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6146494A (en) * 1997-06-12 2000-11-14 The Procter & Gamble Company Modified cellulosic fibers and fibrous webs containing these fibers
FR2965570B1 (fr) * 2010-09-30 2012-11-02 Arjo Wiggins Fine Papers Ltd Procede de raffinage en milieu enzymatique d'une pate papetiere comportant des fibres cellulosiques afin de reduire leur longueur
US9145640B2 (en) 2013-01-31 2015-09-29 University Of New Brunswick Enzymatic treatment of wood chips
US9127401B2 (en) 2013-01-31 2015-09-08 University Of New Brunswick Wood pulp treatment
FI126698B (en) * 2013-12-18 2017-04-13 Teknologian Tutkimuskeskus Vtt Oy Currently for the production of fibrillated cellulose material

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA758488A (en) * 1967-05-09 C. Jenness Lyle Process for treating paper pulp
DK73891D0 (da) * 1991-04-22 1991-04-22 Novo Nordisk As Enzymbehandling

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO9628606A1 *

Also Published As

Publication number Publication date
SE9500846L (sv) 1996-10-31
WO1996028606A1 (fr) 1996-09-19
SE506440C2 (sv) 1997-12-15
SE9500846D0 (sv) 1995-03-09

Similar Documents

Publication Publication Date Title
Oksanen et al. The effect of Trichoderma reesei cellulases and hemicellulases on the paper technical properties of never-dried bleached kraft pulp
Khandeparkar et al. Application of thermoalkalophilic xylanase from Arthrobacter sp. MTCC 5214 in biobleaching of kraft pulp
Pala et al. Enzymatic upgrade of old paperboard containers
US20090107643A1 (en) Method For Mechanical Pulp Production
US10570562B2 (en) Methods for reducing content of hexenuronic acids in cellulosic pulp
FI81394B (fi) Foerfarande foer behandling av massa med enzymer.
Desai et al. Biodeinking of old newspaper pulp using a cellulase-free xylanase preparation of Aspergillus niger DX-23
CA2457785C (fr) Traitement enzymatique de la pate pour augmenter sa resistance au moyen d'enzymes hydrolytiques tronques
Chapla et al. Assessment of a thermostable xylanase from Paenibacillus sp. ASCD2 for application in prebleaching of eucalyptus kraft pulp
Nathan et al. Low Molecular Weight Xylanase from Trichoderma viride VKF3 for Bio-bleaching of Newspaper Pulp.
AU2002259075A1 (en) Enzymatic treatment of pulp to increase strength
Sango et al. Partial purification of bacterial cellulo-xylanolytic enzymes and their application in deinking of photocopier waste paper
EP0524220B1 (fr) Un procede de mise en pate en utilisant de la cellulase
Kaur et al. Application of microbial enzymes in dissolving pulp production
CA2541229C (fr) Methode modifiee de production de pate mecanique
WO2002022943A1 (fr) Procede pour desencrer des vieux papiers au moyen d'une cellulase, sans diminuer la resistance du papier, et procede d'evaluation
EP0813629A1 (fr) Procede pour produire des pates a papier constituees de fibres courtes, a partir de bois de coniferes
Rashmi et al. Enzymatic refining of pulps: an overview
Wu et al. Comparative characterization of a recombinant Volvariella volvacea endoglucanase I (EG1) with its truncated catalytic core (EG1-CM), and their impact on the bio-treatment of cellulose-based fabrics
Rashmi et al. Enzymatic treatment of secondary fibres for improving drainage: An overview
Ozer et al. Distinctive delignification with consecutive application of Geobacillus sp. 71 xylanase and Rhodococcus jostii rha1 lignin peroxidase
Spiridon et al. Enzymatic hydrolysis of Pinus pinaster kraft pulp
Viikari et al. Cellulases in pulp and paper processing
Pawlak Biochemical additives for papermaking
VIIKARI J. BUCHERT, T. OKSANEN, J. PERE, M. SIIKA-AHO, A. SUURNÄKKI and

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 19971009

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT DK FI FR SE

17Q First examination report despatched

Effective date: 20010502

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20011113