EP0511695B1 - Verfahren zum Bleichen von Lignocellulose enthaltendem Zellstoff - Google Patents

Verfahren zum Bleichen von Lignocellulose enthaltendem Zellstoff Download PDF

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Publication number
EP0511695B1
EP0511695B1 EP92201005A EP92201005A EP0511695B1 EP 0511695 B1 EP0511695 B1 EP 0511695B1 EP 92201005 A EP92201005 A EP 92201005A EP 92201005 A EP92201005 A EP 92201005A EP 0511695 B1 EP0511695 B1 EP 0511695B1
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EP
European Patent Office
Prior art keywords
pulp
magnesium
bleaching
process according
hydrogen peroxide
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Expired - Lifetime
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EP92201005A
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English (en)
French (fr)
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EP0511695A1 (de
EP0511695B2 (de
Inventor
Lennart Andersson
Jiri Basta
Lillemor Holtinger
Jan Höök
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Nouryon Pulp and Performance Chemicals AB
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Eka Chemicals AB
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Application filed by Eka Chemicals AB filed Critical Eka Chemicals AB
Priority to EP94203640A priority Critical patent/EP0679760B1/de
Publication of EP0511695A1 publication Critical patent/EP0511695A1/de
Publication of EP0511695B1 publication Critical patent/EP0511695B1/de
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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
    • D21C9/10—Bleaching ; Apparatus therefor
    • D21C9/16—Bleaching ; Apparatus therefor with per compounds
    • D21C9/163—Bleaching ; Apparatus therefor with per compounds with peroxides
    • 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
    • D21C9/10—Bleaching ; Apparatus therefor
    • D21C9/1005—Pretreatment of the pulp, e.g. degassing the pulp
    • 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
    • D21C9/10—Bleaching ; Apparatus therefor
    • D21C9/1026—Other features in bleaching processes
    • D21C9/1036—Use of compounds accelerating or improving the efficiency of the processes
    • 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
    • D21C9/10—Bleaching ; Apparatus therefor
    • D21C9/147—Bleaching ; Apparatus therefor with oxygen or its allotropic modifications
    • D21C9/153—Bleaching ; Apparatus therefor with oxygen or its allotropic modifications with ozone

Definitions

  • the present invention relates to a process for delignification and bleaching of chemically digested lignocellulose-containing pulp.
  • the pulp is bleached at a pH of between about 1 and about 6, whereupon a water-soluble compound containing an alkaline earth metal is added at a pH of between about 1 and about 7 before the pulp is treated with a chlorine-free bleaching agent.
  • the initial acidic treatment removes the trace metals of the pulp, whereas the subsequent addition of alkaline earth metal ions in aqueous solution returns the ions to the positions in the pulp where they have a particularly beneficial effect on the preservation of the cellulose chains and, consequently, on the viscosity, as well as on the consumption of bleaching agent in the subsequent bleaching step.
  • the pulp may be finally bleached to the desired brightness, suitably with a chlorine-free bleaching agent, such a ozone, to completely avoid formation and discharge of AOX.
  • chlorine-free bleaching agents such as hydrogen peroxide, peracetic acid or ozone
  • the delignification and consumption of the bleaching agent become less effective than with chlorine-containing bleaching agents, unless the pulp is pretreated.
  • a hydrogen peroxide treatment in an alkaline environment is disturbed by the presence in the pulp of ions of certain metals, such as Mn, Cu and Fe. These metal ions cause degradation of hydrogen peroxide, thereby reducing the efficiency of the peroxide treatment and increasing the consumption of peroxide.
  • this can be counteracted by pretreating the pulp with an acid, such as sulphuric acid or nitric acid, whereby the concentration of all types of metal ions is reduced.
  • an acid such as sulphuric acid or nitric acid
  • metal ions for example Mg, which are advantageous to the peroxide treatment disappear, which ions stabilize the peroxide and increase the selectivity of the peroxide.
  • CA-A-575,636 discloses the addition of magnesium sulphate to stabilize alkaline peroxide solutions. However, the addition is made directly to the bleaching liquor and in alkaline environment insoluble magnesium hydroxide precipitates. Furthermore, US-A-4,222,819 discloses the addition of magnesium ions to acidic peroxide solutions, but also in this case the addition is made directly to the bleaching liquor. None of the related methods makes possible diffusion of the magnesium ions into the pulp to such an extent, that a pulp of high brightness and strength can be obtained.
  • US-A-3,507,744 relates to a bleaching process for wood pulp, where the pulp is contacted with an alkaline solution containing hydrogen peroxide and further a pyrophosphate to stabilize the peroxide. The aim of the process is to attain high brightness in a single bleaching step without a substantial loss in yield. The process can be preceded by a pretreatment in one or more steps, for example acid treatment and/or addition of barium or calcium salts.
  • DE-A-2022866 describes the use of acid waste liquids deriving from pulp bleaching, with Cl 2 /ClO 2 , to carry out an acid pretreatment, i.e. a washing stage. Since the waste liquids derives from a bleaching stage where Cl 2 /ClO 2 are used as active bleaching chemicals, there will be no, or a unsignificant amount of Cl 2 /ClO 2 remaining in the waste liquids.
  • the invention provides a process in which lignocellulose-containing pulp is treated under the conditions disclosed in the claims, whereby the metal ions harmful to the subsequent bleaching are effectively removed and the profile of alkaline earth metals is restored before the pulp is bleached in a chlorine-free bleaching step.
  • the invention relates to a process for bleaching of chemically digested lignocellulose-containing pulp as described in claim 1, wherein the pulp is bleached at a pH in the range from about 1 up to about 6, whereupon a Mg compound is added at a pH in the range from about 1 up to about 7 and in an amount of from about 0.01 kg, suitably 0.5 kg, up to about 10 kg/ton of dry pulp, calculated as magnesium, and that the pulp subsequently is treated with a chlorine-free bleaching agent, i.e. hydrogen peroxide.
  • a chlorine-free bleaching agent i.e. hydrogen peroxide.
  • Acid treatment is an effective process to eliminate metal ions from lignocellulose-containing pulps.
  • ions of alkaline earth metals especially when in their original positions in the pulp, have a positive influence on the selectivity of the delignification as well as on the stability and consumption of chlorine-free bleaching agents, such as peroxides, ozone and oxygen.
  • the present process presents an economic solution to the problem of creating a suitable trace-metal profile for the subsequent chlorine-free bleaching, in that non-desirable metal ions are eliminated while supplied ions of magnesium essentially recover the positions in the vicinity of the cellulose chains previously occupied by ions of alkaline earth metals.
  • an advantage of the present process is that the pH adjustment between the treatment with acid and addition of magnesium ions becomes very limited or may be left out altogether, which is advantageous to process technique and economy.
  • Chlorine-free bleaching agents include inorganic peroxide compounds, such as hydrogen peroxide and sodium peroxide, organic peroxide compounds, such as peracetic acid, as well as ozone, oxygen and sodium dithionite.
  • inorganic peroxide compounds such as hydrogen peroxide and sodium peroxide
  • organic peroxide compounds such as peracetic acid
  • ozone oxygen and sodium dithionite.
  • hydrogen peroxide (P), oxygen (O) and ozone (Z) are used in a sequence or mixture.
  • the sequence P-Z or (PO)-Z are especially preferred.
  • pH is suitably adjusted by adding to the pulp an alkali or an alkali-containing liquid, such as sodium carbonate, sodium hydrogen carbonate, sodium hydroxide, oxidized white liquor or magnesium hydroxide slurry.
  • an alkali or an alkali-containing liquid such as sodium carbonate, sodium hydrogen carbonate, sodium hydroxide, oxidized white liquor or magnesium hydroxide slurry.
  • the magnesium hydroxide slurry is taken from the chemical handling system in the production of sulphite pulp with magnesium as base, i.e. magnefite pulp.
  • the acid bleaching step suitably is carried out with an acid and the respective bleaching agent.
  • the acids used are inorganic acids, suitably sulphuric acid, nitric acid, hydrochloric acid or residual acid from a chlorine dioxide reactor, either separately or in an optional mixture.
  • sulphuric acid is employed.
  • Compounds containing magnesium relate to water-soluble chemicals containing magnesium or mixtures of water-soluble chemicals containing magnesium and calcium.
  • Use is suitably made of magnesium-containing compounds such as magnesium sulphate or magnesium chloride, or calcium-containing compounds such as calcium chloride or calcium oxide.
  • Use is preferably made of magnesium sulphate or magnesium chloride, the use of magnesium sulphate being especially preferred.
  • the combination of temperature and pH at the addition of the compound containing magnesium is always so chosen that the compound is in aqueous solution when contacted with the pulp.
  • the acid bleaching step is carried out at a pH of from about 1 up to about 6, suitably from 1.5 up to 5, preferably from 2 up to 4. It is especially preferred that the acid bleaching step is carried out at a pH of from 2 up to 3.
  • the magnesium addition is made at a pH in the range from about 1 up to about 7, suitably in the range from 2 up to 6, preferably in the range from 2 up to 4. It is especially preferred that the addition of magnesium is made at a pH of from 2 up to 3.
  • the chlorine-free bleaching agent is hydrogen peroxide and the pulp is treated at a pH of from about 8 up to about 12, preferably at a pH of from 10 up to 12. Treatment with the other chlorine-free bleaching agents mentioned above, is carried out within the normal pH ranges for each bleaching agent, which are well-known to the person skilled in the art.
  • the treatment according to the invention is carried out with a washing step between the acid bleaching step and the addition of magnesium ions, such that the trace metals that are harmful to the treatment with a chlorine-free bleaching agent are removed from the pulp suspension.
  • the realization of the process of claim 1 can be carried out at an optional position in the bleaching sequence, e.g. immediately after digestion of the pulp or after an oxygen step.
  • the process according to the invention is preferably applied to pulp that has been delignified in an oxygen step prior to the treatment.
  • Bleaching and/or delignifying chemicals active within the pH range suitable in the acid treatment are chlorine dioxide, ozone, peracetic acid and/or an acid peroxide-containing compound.
  • a combination of acid treatment and bleaching and/or delignifying treatment takes place in an ozone step.
  • Lignocellulose-containing pulps relate to chemical pulps of softwood and/or hardwood digested according to the sulphite, sulphate, soda or organosolv process, or modifications and/or combinations thereof.
  • Use is suitably made of softwood and/or hardwood digested according to the sulphate process, preferably sulphate pulp of hardwood.
  • the treatment according to the invention can be applied to lignocellulose-containing pulps having an initial kappa number within the range from about 5 up to about 40, suitably 7 up to 32, preferably from 10 up to 20.
  • the kappa number is determined according to the standard method SCAN-C 1:77.
  • the acid bleaching step is carried out at a temperature of from about 10 up to about 95°C, suitably from 20 up to 80°C and preferably from 40 up to 80°C, and for a period of time of from about 1 up to about 120 min, suitably from 10 up to 120 min and preferably from 20 up to 40 min.
  • the compound containing magnesium is added at a temperature of from about 10 up to about 95°C, preferably from 40 up to 80°C, and for a period of time of from about 1 up to about 180 min, preferably from 20 up to 180 min and preferably from 30 up to 120 min.
  • the pulp is treated at a temperature of from about 30 up to about 100°C, preferably from 60 up to 90°C, and for a period of time of from about 30 up to about 300 min, suitably from 60 up to 240 min.
  • the pulp concentration may be from about 3 up to about 35% by weight, preferably from 3 up to 15% by weight.
  • the pulp concentration may be from about 3 up to about 50% by weight, suitably from 3 up to 35% by weight and preferably from 10 up to 25% by weight.
  • Treatment with the other chlorine-free bleaching agents mentioned above, is carried out within the normal ranges of temperature, time and pulp concentration for each bleaching agent, which are well-known to the person skilled in the art.
  • the amount of magnesium compound charged lies in the range from about 0.01 up to about 10 kg/ton of dry pulp, calculated as alkaline earth metal, suitably in the range from 0.5 up to 5 kg/ton of dry pulp, calculated as magnesium, and preferably in the range from 2 up to 4 kg/ton of dry pulp, calculated as magnesium.
  • the amount of hydrogen peroxide lies in the range from about 2 up to about 50 kg/ton of dry pulp, calculated as 100% hydrogen peroxide.
  • the upper limit is not critical, but has been set for reasons of economy.
  • the amount of hydrogen peroxide suitably lies in the range from 3 up to 30 kg/ton of dry pulp and preferably from 4 up to 20 kg/ton of dry pulp, calculated as 100% hydrogen peroxide.
  • the pulp can be used for direct production of paper with a lower demand of brightness.
  • the pulp may be finally bleached to the desired higher brightness, by treatment in one or more steps.
  • the final bleaching is also carried out with chlorine-free bleaching agents of the type mentioned above, optionally with intermediate alkaline extraction steps, which may be reinforced with peroxide and/or oxygen. In this way, the formation and discharge of AOX is completely eliminated.
  • the final bleaching is carried out with ozone in one or more steps.
  • the process according to the invention means that the brightness and kappa number of the resulting pulp is higher and lower, respectively, than with the processes in which a compound containing an alkaline earth metal is not added at all or is added at a higher pH.
  • the aim is a high brightness as well as a low kappa number, the latter meaning a low content of undissolved lignin.
  • the consumption of the chlorine-free bleaching agent should be as low as possible meaning lower treatment costs.
  • these objects are met, as is apparent from the Examples.
  • the strength of the pulp measured as viscosity, is sufficient, which means that the pulp contains cellulose chains which are long enough to give a strong product.
  • D and EOP relate to a conventional chlorine dioxide step and a conventional alkaline extraction step reinforced with hydrogen peroxide and oxygen, respectively.
  • Z relates to an ozone step with a pH of 2.3.
  • Mg relates to the addition of 1 kg of magnesium/ton of dry pulp, in the form of an aqueous solution containing MgSO 4 .
  • Step1 relates to treatment with EDTA at a pH of 5.
  • Z relates to an ozone step with a pH of 2.3, the pulp concentration being 10% by weight.
  • Mg relates to the addition of 1 kg of magnesium/ton of dry pulp, in the form of an aqueous solution containing MgSO 4 . Magnesium was added at a pH of 4.1, a temperature of 50°C for 30 min, the pulp concentration being about 3% by weight.
  • P 2 relates to a hydrogen peroxide step, where the pulp was treated at a temperature of 80°C for 120 min. The final pH was about 11.5 and the addition of hydrogen peroxide was 5 kg/ton of dry pulp calculated as 100% hydrogen peroxide.
  • the pulp was also treated in the sequence Step1 - P 1 - Z - (PMg) (test 3).
  • (PMg) relates to the addition of magnesium in the second alkaline hydrogen peroxide step under the conditions stated above, in accordance with the prior art.
  • the viscosity and brightness were determined according to SCAN Standard Methods, and the consumption of hydrogen peroxide was determined by iodometric titration. The results after the second hydrogen peroxide step appear from the Table below.

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  • Engineering & Computer Science (AREA)
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  • Compositions Of Macromolecular Compounds (AREA)
  • Polysaccharides And Polysaccharide Derivatives (AREA)
  • Processes Of Treating Macromolecular Substances (AREA)
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  • Investigating Or Analysing Biological Materials (AREA)
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Claims (10)

  1. Verfahren zum Entholzen und Bleichen von chemisch aufgeschlossenem lignocellulosehaltigem Zellstoff, dadurch gekennzeichnet. daß der Zellstoff bei einem pH-Wert im Bereich von etwa 1 bis etwa 6 mit einer aus Chlordioxid, Ozon. Peressigsäure und Säureperoxiden ausgewählten Bleichchemikalie gebleicht wird, wonach der Zellstoff gewaschen wird, worauf eine Magnesium enthaltende wasserlösliche Chemikalie bei einem pH-Wert im Bereich von etwa 1 bis etwa 7 und in einer Menge von etwa 0.01 bis etwa 10 kg/Tonne trockener Zellstoff, berechnet als Magnesium, zugegeben wird, und daß der Zellstoff anschließend bei einem pH-Wert von etwa 8 bis etwa 12 mit Wasserstoffperoxid gebleicht wird.
  2. Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß der Zellstoff anschließend bei einem pH-Wert von 10 bis 12 mit Wasserstoffperoxid gebleicht wird.
  3. Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß der chemisch aufgeschlossene Zellstoff Sulfatzellstoff ist.
  4. Verfahren nach Anspruch 1. dadurch gekennzeichnet, daß die Magnesium enthaltende wasserlösliche Chemikalie bei einem pH-Wert von 2 bis 6 zugegeben wird.
  5. Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß die Magnesium enthaltende wasserlösliche Chemikalie ein Gemisch aus magnesiumhaltigen und calciumhaltigen Verbindungen ist.
  6. Verfahren nach Anspruch 1 oder 5, dadurch gekennzeichnet, daß die Magnesium enthaltende wasserlösliche Chemikalie aus Magnesiumsulfat oder Magnesiumchlorid besteht.
  7. Verfahren nach Anspruch 5, dadurch gekennzeichnet, daß die Calcium enthaltende wasserlösliche Chemikalie aus Calciumchlorid oder Calciumoxid besteht.
  8. Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß das Bleichen vor der Zugabe einer Magnesium enthaltenden wasserlöslichen Chemikalie bei einem pH-Wert im Bereich von 1.5 bis 5 durchgeführt wird.
  9. Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß der Zellstoff nach dem Bleichen mit Wasserstoffperoxid bei einem pH-Wert von etwa 8 bis etwa 12 schließlich in einem oder mehreren Schritten mit Ozon gebleicht wird.
  10. Verfahren nach den Ansprüchen 1-9, dadurch gekennzeichnet, daß der Schritt der Säurebleichung bei einer Temperatur von etwa 10 bis etwa 95°C während etwa 1 bis etwa 120 Min. durchgeführt wird, daß die Magnesium enthaltende wasserlösliche Chemikalie bei einer Temperatur von etwa 10 bis 95°C während etwa 1 bis etwa 180 Min. und in einer Menge von 0.5 bis 5 kg/Tonne trockener Zellstoff, berechnet als Magnesium, zugegeben wird. wobei der behandelte Zellstoff eine Konzentration von etwa 3 bis etwa 35 Gew.-% hat.
EP92201005A 1991-04-30 1992-04-08 Verfahren zum Bleichen von Lignocellulose enthaltendem Zellstoff Expired - Lifetime EP0511695B2 (de)

Priority Applications (1)

Application Number Priority Date Filing Date Title
EP94203640A EP0679760B1 (de) 1991-04-30 1992-04-08 Verfahren zum Bleichen von Lignocellulose-enthaltendem Zellstoff

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
SE9101301 1991-04-30
SE9101301A SE470065C (sv) 1991-04-30 1991-04-30 Behandling av kemisk massa med en syra och därefter en magnesium- och kalciumförening vid klorfri blekning

Related Child Applications (2)

Application Number Title Priority Date Filing Date
EP94203640.1 Division-Into 1992-04-08
EP94203640A Division EP0679760B1 (de) 1991-04-30 1992-04-08 Verfahren zum Bleichen von Lignocellulose-enthaltendem Zellstoff

Publications (3)

Publication Number Publication Date
EP0511695A1 EP0511695A1 (de) 1992-11-04
EP0511695B1 true EP0511695B1 (de) 1996-08-28
EP0511695B2 EP0511695B2 (de) 2004-06-02

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ID=20382601

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Application Number Title Priority Date Filing Date
EP94203640A Expired - Lifetime EP0679760B1 (de) 1991-04-30 1992-04-08 Verfahren zum Bleichen von Lignocellulose-enthaltendem Zellstoff
EP92201005A Expired - Lifetime EP0511695B2 (de) 1991-04-30 1992-04-08 Verfahren zum Bleichen von Lignocellulose enthaltendem Zellstoff

Family Applications Before (1)

Application Number Title Priority Date Filing Date
EP94203640A Expired - Lifetime EP0679760B1 (de) 1991-04-30 1992-04-08 Verfahren zum Bleichen von Lignocellulose-enthaltendem Zellstoff

Country Status (14)

Country Link
EP (2) EP0679760B1 (de)
JP (1) JP2592747B2 (de)
AT (2) ATE141971T1 (de)
BR (1) BR9201554A (de)
CA (1) CA2067296C (de)
DE (2) DE69213080D1 (de)
ES (1) ES2091395T3 (de)
FI (1) FI111964B (de)
MX (1) MX9201966A (de)
NO (1) NO180495C (de)
NZ (1) NZ242465A (de)
RU (1) RU2039141C1 (de)
SE (1) SE470065C (de)
ZA (1) ZA923073B (de)

Cited By (1)

* Cited by examiner, † Cited by third party
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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FI89516B (fi) 1989-05-10 1993-06-30 Ahlstroem Oy Foerfarande foer blekning av cellulosamassa med otson
US6398908B1 (en) 1991-04-30 2002-06-04 Eka Nobel Ab Process for acid bleaching of lignocellulose-containing pulp with a magnesium compound
SE500353C2 (sv) * 1992-10-26 1994-06-06 Sca Wifsta Oestrand Ab Peroxidblekning av sulfatmassa med tillsats av magnesium före blekningen
SE512137C2 (sv) * 1992-10-29 2000-01-31 Eka Chemicals Ab Förfarande för blekning av lignocellulosahaltig massa
SE9203366L (sv) * 1992-11-11 1994-05-12 Mo Och Domsjoe Ab Förfarande vid delignifiering och/eller blekning av cellulosamassa
US6007678A (en) * 1992-11-27 1999-12-28 Eka Nobel Ab Process for delignification of lignocellulose-containing pulp with an organic peracid or salts thereof
DE69420306T2 (de) * 1993-04-20 2000-04-20 Eka Chemicals Ab Bohus Verfahren zum Bleichen von Lignozellulose-enthaltendem Zellstoff
SE500616C2 (sv) * 1993-06-08 1994-07-25 Kvaerner Pulping Tech Blekning av kemisk massa med peroxid vid övertryck
US6605181B1 (en) * 1993-10-01 2003-08-12 Kvaerner Pulping Aktiebolag Peroxide bleach sequence including an acidic bleach stage and including a wash stage
BE1007757A3 (fr) * 1993-11-10 1995-10-17 Solvay Interox Procede pour le blanchiment d'une pate a papier chimique.
FI102301B1 (fi) * 1994-10-13 1998-11-13 Ahlstrom Machinery Oy Menetelmä selluloosamassojen käsittelemiseksi
US6776876B1 (en) 1994-10-13 2004-08-17 Andritz Oy Method of treating cellulosic pulp to remove hexenuronic acid
DE19516151A1 (de) 1995-05-03 1996-11-07 Sven Siegle Verfahren zur Herstellung einer Pulpe aus zellulosehaltigem Material, die Pulpe selbst und deren Verwendung
FI105701B (fi) 1995-10-20 2000-09-29 Ahlstrom Machinery Oy Menetelmä ja laitteisto massan käsittelemiseksi
JPH108092A (ja) * 1996-06-21 1998-01-13 Mitsubishi Paper Mills Ltd 過酸化物漂白用安定化剤及びそれを用いた繊維系物質の漂白方法
BE1010679A3 (fr) * 1996-10-11 1998-11-03 Solvay Interox Procede de delignification et de blanchiment de pate a papier chimique.
ID23571A (id) * 1997-08-25 2000-05-04 Praxair Technology Inc Metoda penerapan ozon dalam pemutihan ecf
JP2002266272A (ja) * 2001-03-12 2002-09-18 Nippon Paper Industries Co Ltd セルロース質繊維材料パルプの漂白方法
US6743332B2 (en) * 2001-05-16 2004-06-01 Weyerhaeuser Company High temperature peroxide bleaching of mechanical pulps
KR100547491B1 (ko) * 2005-04-27 2006-01-31 이권혁 대나무를 이용하여 생산하는 섬유용 펄프의 제조방법 및 그 펄프
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EP2714987B1 (de) 2011-05-23 2015-07-29 GP Cellulose GmbH Weichholz-kraftfaser mit verbesserter weisse und helligkeit sowie verfahren zu ihrer herstellung und verwendung
MX366988B (es) 2012-01-12 2019-08-01 Gp Cellulose Gmbh Fibra kraft de baja viscosidad que tiene propiedades de amarillez reducida, y metodos para prepararla y usarla.
EP2839071B1 (de) 2012-04-18 2019-01-23 GP Cellulose GmbH Verwendung eines tensids zur behandlung von pulpe und zur verbesserung der aufnahme von kraft-pulpe in fasern zur herstellung von viskose und anderen sekundären faserprodukten
US9115468B2 (en) * 2012-09-27 2015-08-25 Andritz Inc. Chemical treatment of lignocellulosic fiber bundle material, and methods and systems relating thereto
WO2014122533A2 (en) 2013-02-08 2014-08-14 Gp Cellulose Gmbh Softwood kraft fiber having an improved a-cellulose content and its use in the production of chemical cellulose products
RU2671653C2 (ru) 2013-03-14 2018-11-06 ДжиПи СЕЛЛЬЮЛОУС ГМБХ Способ изготовления высокофункционального маловязкого крафтволокна с использованием последовательности кислотного отбеливания и волокно, изготовленное с помощью этого процесса
JP6521873B2 (ja) 2013-03-15 2019-05-29 ゲーペー ツェルローゼ ゲーエムベーハー 増強されたカルボキシル含量を有する低粘度クラフト繊維ならびにその製造方法および使用方法
BR112017027022B1 (pt) * 2015-09-30 2023-04-18 Imerys Minerals Limited Método para formação de uma composição para branqueamento de massas celulósicas aquosas, composição e kit de ingredientes
EP3541849B1 (de) 2016-11-16 2023-11-15 GP Cellulose GmbH Modifizierte cellulose aus chemischen fasern und methoden zu deren herstellung und verwendung
WO2021209586A1 (en) * 2020-04-16 2021-10-21 Bim Kemi Ab Delignification process

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3507744A (en) * 1966-04-01 1970-04-21 Kimberly Clark Co Wood pulp bleaching process utilizing peroxide pyrophosphate high concentration compositions
SE335053B (de) * 1969-05-13 1971-05-10 Mo Och Domsjoe Ab
DE2742262C2 (de) * 1977-09-20 1982-06-09 Degussa Ag, 6000 Frankfurt Verfahren zur Herstellung eines mittel- bis hochviskosen Nadelholz-Sulfitzellstoffs
FR2520397A1 (fr) * 1982-01-28 1983-07-29 Centre Tech Ind Papier Procede pour le traitement de pates papetieres chimiques
FR2557605B1 (fr) * 1983-12-29 1987-12-11 Atochem Procede de blanchiment de pates papetieres par le peroxyde d'hydrogene
JPH0364589A (ja) * 1989-07-28 1991-03-19 Mitsubishi Gas Chem Co Inc 化学パルプの漂白方法

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10731293B2 (en) 2009-05-28 2020-08-04 Gp Cellulose Gmbh Modified cellulose from chemical kraft fiber and methods of making and using the same

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DE69227640T2 (de) 1999-05-06
CA2067296A1 (en) 1992-10-31
CA2067296C (en) 1997-03-04
SE9101301L (sv) 1992-10-31
FI111964B (fi) 2003-10-15
EP0679760A1 (de) 1995-11-02
JPH05148784A (ja) 1993-06-15
FI921886A (fi) 1992-10-31
BR9201554A (pt) 1992-12-01
ATE141971T1 (de) 1996-09-15
DE69213080D1 (de) 1996-10-02
SE470065B (sv) 1993-11-01
NO921671L (no) 1992-11-02
NO180495B (no) 1997-01-20
EP0511695A1 (de) 1992-11-04
ES2091395T3 (es) 1996-11-01
AU1514992A (en) 1993-03-11
RU2039141C1 (ru) 1995-07-09
SE470065C (sv) 1995-10-12
SE9101301D0 (sv) 1991-04-30
NZ242465A (en) 1993-12-23
EP0679760B1 (de) 1998-11-18
NO921671D0 (no) 1992-04-29
AU651192B2 (en) 1994-07-14
ZA923073B (en) 1992-12-30
EP0511695B2 (de) 2004-06-02
MX9201966A (es) 1992-11-01
NO180495C (no) 2003-06-06
DE69227640D1 (de) 1998-12-24
FI921886A0 (fi) 1992-04-27
ATE173518T1 (de) 1998-12-15
JP2592747B2 (ja) 1997-03-19

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