EP0476230A2 - Verlängertes Kraftkochen mit dem Waschkreislauf zugefügter Weisslauge - Google Patents

Verlängertes Kraftkochen mit dem Waschkreislauf zugefügter Weisslauge Download PDF

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Publication number
EP0476230A2
EP0476230A2 EP91108241A EP91108241A EP0476230A2 EP 0476230 A2 EP0476230 A2 EP 0476230A2 EP 91108241 A EP91108241 A EP 91108241A EP 91108241 A EP91108241 A EP 91108241A EP 0476230 A2 EP0476230 A2 EP 0476230A2
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EP
European Patent Office
Prior art keywords
digester
kraft
white liquor
recirculation loop
liquor
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.)
Granted
Application number
EP91108241A
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English (en)
French (fr)
Other versions
EP0476230A3 (en
EP0476230B1 (de
Inventor
Bertil Kamyr Inc. Stromberg
Jian Kamyr Inc. Jiang
Richard Kamyr Inc. Laakso
Joseph Kamyr Center Phillips
Brian Kamyr Center Greenwood
James Kamyr Inc. Prough
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.)
Kamyr Inc
Original Assignee
Kamyr Inc
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Filing date
Publication date
Application filed by Kamyr Inc filed Critical Kamyr Inc
Publication of EP0476230A2 publication Critical patent/EP0476230A2/de
Publication of EP0476230A3 publication Critical patent/EP0476230A3/en
Application granted granted Critical
Publication of EP0476230B1 publication Critical patent/EP0476230B1/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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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
    • D21C9/147—Bleaching ; Apparatus therefor with oxygen or its allotropic modifications
    • 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
    • D21C3/02—Pulping cellulose-containing materials with inorganic bases or alkaline reacting compounds, e.g. sulfate 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
    • D21C3/00—Pulping cellulose-containing materials
    • D21C3/22—Other features of pulping processes
    • D21C3/24—Continuous 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
    • D21C7/00—Digesters
    • 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
    • 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

Definitions

  • a method of continuously kraft pulping comminuted cellulosic fibrous materials utilizing an upright digester having a top, bottom, and central portions comprises the following steps: (a) passing comminuted cellulosic fibrous material entrained in kraft white liquor into the top of the digester; (b) extracting black liquor from at least one screen between the top and bottom of the digester; (c) at a first portion of the digester withdrawing and recirculating liquid in a first recirculation loop; (d) adding wash liquid at the bottom of the digester; (e) adjacent to the bottom of the digester withdrawing and recirculating liquid in a second, wash, recirculation loop; (f) adding kraft white liquor to the second recirculation loop, the liquor recirculated into the digester in part passing upwardly therein countercurrent to the material flow; and the amount of white liquor added in this second recirculation loop being sufficient to increase the viscosity and strength properties of the
  • step (b) is practiced between the top and central portion of the digester, and step (c) at the central portion, and there is the further step (h) of adding kraft white liquor into the first circulation loop.
  • the amount of kraft white liquor added in the second recirculation loop is at least about 5%, and preferably about 10-20% (e.g. 15%) of the total white liquor necessary to effect kraft pulping.
  • the amount of kraft white liquor added in step (h) is preferably at least about 10% of the total amount of kraft white liquor necessary to effect kraft pulping, preferably about 10-20%.
  • an apparatus for continuously kraft pulping comminute cellulosic fibrous material comprises: an upright digester vessel, having a top, bottom, and central portion; means for introducing comminuted cellulosic fibrous material entrained in white liquor into the top of the digester; means for extracting black liquor from at lest one screen between the top of the digester and the central portion thereof; at the central portion of the digester, means for withdrawing and recirculating liquid in a first circulation loop; means for adding wash liquid to the bottom of the digester; adjacent the bottom of the digester, means for withdrawing and recirculating liquid in a second, wash, recirculation loop; means for withdrawing kraft pulp from the bottom of the digester; and means for introducing white liquor into said second recirculation loop.
  • Means are also preferably provided for introducing white liquor into the first recirculation loop.
  • Each recirculation loop comprises a withdrawal conduit, pump, heater, and re-introduction conduit.
  • the means for introducing white liquor into each recirculation loop comprises means for introducing the liquor into the withdrawal conduit before the pump and heater
  • another method of continuously kraft pulping cellulosic material comprises all the steps of: (a) passing comminuted cellulosic fibrous material entrained in kraft white liquor into the top of the digester; (b) extracting black liquor from at least one screen between the top and central portion of the digester; (c) at the central portion of the digester withdrawing and recirculating liquid in a first circulation loop; (d) adding kraft white liquor to the liquid in the first recirculation loop; (e) adding wash liquid at the bottom of the digester; (f) adjacent the bottom of the digester withdrawing and recirculating liquid in a second, wash, recirculation loop; (g) withdrawing kraft pulp from the bottom of the digester; and (h) increasing the viscosity of the kraft pulp produced, at a given Kappa Number, by at least about 20% compared to pulp produced by the practice of only the steps (a) - (g), by adding kraft white liquor to the second
  • FIG. 1 An exemplary apparatus for kraft pulping according to the invention is illustrated in Figure 1.
  • Entirely standard components include a chips bin 10 for receiving a feed of chips 11 or like cellulosic comminuted fibrous material. From the chips bin 10, the material goes to a horizontal steaming vessel 12, and a vertical conduit 13, kraft white liquor from the source 14 being added to the material in the conduit 13 to slurry the material as it is fed to the high pressure feeder 15. From the high pressure feeder 15 the material entrained in kraft white liquor passes to an optional impregnation vessel 16, and then in line 17 to the top 18 of a continuous digester 19. At the top of the digester 19 there is a liquid/material separation device 20, which preferably comprises a plurality of bull screens with switching withdrawal from the screens, or the like. The digester 19 also includes a central portion 21 and a bottom 22.
  • one or more screens 23, and conduit 24, are provided as means for extracting black liquor from the digester 19.
  • the black liquor is typically passed in conduit 24 to a series of flash tanks 25, as is conventional.
  • withdrawal screens 27 are also provided, being connected by a withdrawal conduit to a pump 28 and a heater 29 for re-introduction of the withdrawn liquid at point 30 of a re-introduction conduit, the point 30 typically being slightly above the screens 27.
  • kraft pulp is withdrawn in conduit 33 (a scraper or like conventional components can also be utilized), and wash liquor from source 34 is added in introduction conduit 35.
  • a wash screen (one or more rows) 37 Adjacent the bottom of the digester 19 a wash screen (one or more rows) 37 is provided, liquid being withdrawn therethrough in a withdrawal conduit under the influence of pump 38, and then passing through heater 39 into a re-introduction conduit to be introduced at point 40 just above the screen 37. From the point 40 up to the screens 23, liquid flows countercurrently to the material -- as designated by arrows 42 -- while above the screens 23 it flows cocurrently.
  • a conduit 46 is provided for interconnecting the main conduit 44 to the withdrawal conduit in the second, wash, recirculation loop provided by elements 37 through 40.
  • sufficient kraft white liquor is added in conduit 46 so as to achieve significantly enhanced viscosity and strength properties of the pulp produced compared to the practice of the same method without the introduction of kraft white liquor in conduit 46.
  • the amount of kraft white liquor added in conduit 46 is at least about 5% of the total amount of kraft liquor utilized to effect kraft pulping, and typically is about 10-20% (e.g. about 15%).
  • Kraft white liquor preferably is also added -- as is known per se -- in conduit 45 in addition to conduit 46, the amount added in conduit 45 being at least about 10%, and preferably about 10-20%.
  • the apparatus of Figure 1 also includes a recirculation loop at a central portion of the impregnation vessel 16, including screen 48, withdrawal conduit 49, pump 50, and re-introduction conduit/point 51.
  • Kraft white liquor from source 14 also is preferably added as indicated by lines or points 52, 53, 54 to the recirculation loop in the impregnation vessel 16, and to the recirculation conduits from the digester to the impregnation vessel 16, and from the impregnation vessel 16 to the high pressure feeder 15.
  • Normally the majority of the white liquor used in the conventional continuous kraft pulping process is added at the points or conduits 52 - 54.
  • FIG. 2 Graphical representations of some of the improved results achieved according to the present invention are illustrated in Figures 2 and 3.
  • the first procedure -- illustrated by line 55 -- is conventional continuous kraft cooking.
  • the second procedure -- illustrated by line 56 -- is for the Kamyr MCCTM system and process.
  • the data points 57 illustrate results achieved by practicing the present invention.
  • all parameters were maintained essentially the same except for the addition of kraft white liquor, and the temperature in the wash zone according to the invention was raised to about 140-175°C, compared to about 125-130°C for conventional kraft cooking and Kamyr's MCCTM process.
  • the conditions resulting in the plots in Figures 2 and 3 are set forth in the following table:
  • the addition of white liquor at 53 is normally about 50-60% of the total white liquor added, and about 10-20% at 54 (with about 10-20% at 45, and 5-20% at 46).
  • Figure 3 graphically illustrates the same test results as Figure 2, only the viscosity/Kappa Number ratio is plotted against Kappa Number.
  • the graphical representation 60 is attained during conventional kraft cooking, the graphical representation 61 during the practice of the Kamyr MCCTM process and system, and the data points 62 in the practice of the present invention.
  • the viscosity of the plots produced according to the invention is at least 30% greater than for the best prior art system (MCCTM), and can under almost all circumstances be expected to be at least 20% greater.
  • the viscosity of the final pulp produced increase, the strength properties (tear, tensile, and burst) are also increased for a given Kappa Number. Further, unexpectedly, the entire digester becomes easier to operate. The easier operation of the digester alone is enough to warrant utilization of the method according to the invention.

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  • Engineering & Computer Science (AREA)
  • Wood Science & Technology (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Inorganic Chemistry (AREA)
  • Paper (AREA)
  • Cookers (AREA)
  • Pharmaceuticals Containing Other Organic And Inorganic Compounds (AREA)
  • Diaphragms For Electromechanical Transducers (AREA)
  • Physical Or Chemical Processes And Apparatus (AREA)
  • Detergent Compositions (AREA)
  • Medicines Containing Antibodies Or Antigens For Use As Internal Diagnostic Agents (AREA)
  • Nitrogen Condensed Heterocyclic Rings (AREA)
EP91108241A 1990-09-17 1991-05-22 Verlängertes Kraftkochen mit dem Waschkreislauf zugefügter Weisslauge Expired - Lifetime EP0476230B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US58304390A 1990-09-17 1990-09-17
US583043 1990-09-17

Publications (3)

Publication Number Publication Date
EP0476230A2 true EP0476230A2 (de) 1992-03-25
EP0476230A3 EP0476230A3 (en) 1993-06-09
EP0476230B1 EP0476230B1 (de) 1996-12-18

Family

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Family Applications (1)

Application Number Title Priority Date Filing Date
EP91108241A Expired - Lifetime EP0476230B1 (de) 1990-09-17 1991-05-22 Verlängertes Kraftkochen mit dem Waschkreislauf zugefügter Weisslauge

Country Status (10)

Country Link
EP (1) EP0476230B1 (de)
JP (1) JP3029492B2 (de)
AT (1) ATE146538T1 (de)
BR (1) BR9103650A (de)
CA (1) CA2037717C (de)
DE (1) DE69123670D1 (de)
FI (1) FI103815B (de)
NO (1) NO179918C (de)
RU (1) RU2089694C1 (de)
ZA (1) ZA912117B (de)

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0557112A1 (de) * 1992-02-21 1993-08-25 Kamyr, Inc. Verfahren zum chlorfreien Aufschluss und Bleichen
WO1994009203A1 (en) * 1992-10-20 1994-04-28 Kamyr, Inc. Completely countercurrent cook continuous digester
WO1994011566A1 (en) * 1992-11-18 1994-05-26 Kamyr Aktiebolag Process for continuous cooking of pulp
WO1994011567A1 (en) * 1992-11-18 1994-05-26 Kvaerner Pulping Technologies Ab Method of continuously cooking pulp
WO1994024362A1 (en) * 1993-04-20 1994-10-27 Kamyr Ab Method of continuously cooking pulp
WO1994025668A1 (en) * 1993-05-04 1994-11-10 Kamyr, Inc. Dissolved solids control in pulp production
WO1995013419A1 (en) * 1993-11-08 1995-05-18 Kamyr, Inc. Implementation of dissolved solids profiling
WO1996006217A1 (en) * 1994-08-18 1996-02-29 Kamyr, Inc. Enhancements in pulping with dissolved solids control
WO1996007786A1 (en) * 1994-09-02 1996-03-14 Kamyr, Inc. Continuous kraft cooking with black liquor pretreatment
US5593544A (en) * 1993-07-12 1997-01-14 Kvaerner Pulping Aktiebolag Pulp production
WO1997029236A1 (en) * 1996-02-09 1997-08-14 Kvaerner Pulping Ab Method for continuous cooking of cellulose-containing fibre material
US5766413A (en) * 1993-04-23 1998-06-16 Kvaerner Pulping Ab Process for isothermal cooking pulp in a continuous digester
US5824188A (en) * 1993-05-04 1998-10-20 Ahlstrom Machinery Inc. Method of controlling the pressure of a continuous digester using an extraction-dilution
WO1999020830A1 (fr) * 1997-10-17 1999-04-29 Solvay (Societe Anonyme) Fabrication de pate a papier chimique
US6132556A (en) * 1993-05-04 2000-10-17 Andritz-Ahlstrom Inc. Method of controlling pulp digester pressure via liquor extraction
WO2002075044A1 (en) * 2001-03-21 2002-09-26 Kvaerner Pulping Ab Continuous digester for cellulose pulp including method and recirculation system for such digester
EP2034090A1 (de) 2007-08-07 2009-03-11 Andritz, Inc. Verfahren und Vorrichtung zum semi-chemischen Aufschliessen
AU2008203206B2 (en) * 2007-08-07 2011-12-15 Andritz Inc. Method and System for Semi-Chemical Pulping
EP3018251A1 (de) * 2014-11-07 2016-05-11 Valmet AB Verfahren zur rückgewinnung von hydrolysat in einem prehydrolysesulfat-kochverfahren für zellstoffherstellung

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SE0004049L (sv) * 2000-11-03 2001-11-05 Kvaerner Pulping Tech Kontinuerlig kokning av massa med avdrag av begagnad koklut dels från kokaren, dels från en efterföljande tryckdiffusör
SE517674E8 (sv) * 2001-05-02 2015-10-20 Metso Paper Sweden Ab Förfarande för tvättvätsketillförsel till kokningsprocess för cellulosamassa
GB0119237D0 (en) * 2001-08-07 2001-10-03 Bioregional Minimills Uk Ltd Paper plant
RU2407768C2 (ru) * 2005-06-03 2010-12-27 Андриц Аг Способ снижения потребления электроэнергии при производстве термомеханической древесной массы посредством высокотемпературного размола древесной массы низкой и средней концентрации
RU2335590C1 (ru) * 2007-01-16 2008-10-10 Витаутас Валентинович Сенкус Способ изготовления устойчивой железнодорожной шпалы с использованием отходов горно-металлургического производства
US7828930B2 (en) * 2007-11-20 2010-11-09 International Paper Company Use of polysulfide in modified cooking

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3215588A (en) * 1963-08-15 1965-11-02 Lummus Co Continuous impregnation, cooking, and washing of fibrous material
US3427218A (en) * 1964-07-10 1969-02-11 Kamyr Ab Method of performing counter-current continuous cellulose digestion
US5053108A (en) * 1989-06-28 1991-10-01 Kamyr Ab High sulfidity cook for paper pulp using black liquor sulfonization of steamed chips

Cited By (48)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0557112A1 (de) * 1992-02-21 1993-08-25 Kamyr, Inc. Verfahren zum chlorfreien Aufschluss und Bleichen
US5401361A (en) * 1992-08-19 1995-03-28 Kamyr, Inc. Completely coutercurrent cook continuous digester
WO1994009203A1 (en) * 1992-10-20 1994-04-28 Kamyr, Inc. Completely countercurrent cook continuous digester
RU2113574C1 (ru) * 1992-11-18 1998-06-20 Кваернер Палпинг Технолоджиз АБ Вертикальный варочный котел для варки волокнистого материала
US5470437A (en) * 1992-11-18 1995-11-28 Kvaerner Pulping Technologies Ab Digester for cooking pulp having staggered screens
WO1994011567A1 (en) * 1992-11-18 1994-05-26 Kvaerner Pulping Technologies Ab Method of continuously cooking pulp
AU684759B2 (en) * 1992-11-18 1998-01-08 Kvaerner Pulping Ab Digester for continuous cooking of fibre material
US5591303A (en) * 1992-11-18 1997-01-07 Kvaerner Pulping Technologies Ab Process for operating a digester
AU680194B2 (en) * 1992-11-18 1997-07-24 Kvaerner Pulping Ab Digester for continuous cooking of fibre material
WO1994011564A1 (en) * 1992-11-18 1994-05-26 Kvaerner Pulping Technologies Ab Digester for continuous cooking of fibre material
RU2121537C1 (ru) * 1992-11-18 1998-11-10 Кваернер Палпинг Текнолоджиз АБ Вертикальный котел для варки волокнистого материала
WO1994011566A1 (en) * 1992-11-18 1994-05-26 Kamyr Aktiebolag Process for continuous cooking of pulp
WO1994011565A1 (en) * 1992-11-18 1994-05-26 Kvaerner Pulping Technologies Ab Digester for continuous cooking of fibre material
US5919337A (en) * 1992-11-18 1999-07-06 Kvaerner Pulping Technologies Ab Method of continuously isothermally cooking of pulp
RU2126470C1 (ru) * 1992-11-18 1999-02-20 Кваернер Палпинг Теклоноджиз АБ Способ непрерывной варки волоконного материала
WO1994024362A1 (en) * 1993-04-20 1994-10-27 Kamyr Ab Method of continuously cooking pulp
US5766413A (en) * 1993-04-23 1998-06-16 Kvaerner Pulping Ab Process for isothermal cooking pulp in a continuous digester
US6113742A (en) * 1993-04-23 2000-09-05 Kvaerner Pulping Ab Digester having screening arrangement for isothermal cooking of fibrous material
US5849151A (en) * 1993-05-04 1998-12-15 Ahlstrom Machinery Inc. Continuous digester having means for implementing low dissolved solids profiling
US6280568B1 (en) 1993-05-04 2001-08-28 Andritz-Ahlstrom Inc. Dissolved organic material control in a cellulose pulp continuous digester
US6159337A (en) * 1993-05-04 2000-12-12 Andritz-Ahlstrom Inc. Dissolved organic materials control in cellulose pulp production
US5575890A (en) * 1993-05-04 1996-11-19 Kamyr, Inc. Method for selectively increasing the sulfide ion concentration and sulfidity of kraft cooking liquor during kraft cooking of wood
US5536366A (en) * 1993-05-04 1996-07-16 Ahlstrom Machinery Inc. Digester system for implementing low dissolved solids profiling
US5824188A (en) * 1993-05-04 1998-10-20 Ahlstrom Machinery Inc. Method of controlling the pressure of a continuous digester using an extraction-dilution
US6132556A (en) * 1993-05-04 2000-10-17 Andritz-Ahlstrom Inc. Method of controlling pulp digester pressure via liquor extraction
WO1994025668A1 (en) * 1993-05-04 1994-11-10 Kamyr, Inc. Dissolved solids control in pulp production
US5849150A (en) * 1993-05-04 1998-12-15 Ahlstrom Machinery Inc. Low dissolved solids control in pulp production
EP1126075A3 (de) * 1993-05-04 2002-01-02 Andritz-Ahlstrom Inc. Kontrolle der gelösten Feststoffe bei der Zellstoffherstellung
US5489363A (en) * 1993-05-04 1996-02-06 Kamyr, Inc. Pulping with low dissolved solids for improved pulp strength
EP1308555A3 (de) * 1993-05-04 2003-05-28 Andritz Inc. Kontrolle der gelösten Feststoffe bei der Zellstoffherstellung
EP1308554A3 (de) * 1993-05-04 2003-05-28 Andritz Inc. Kontrolle der gelösten Feststoffe bei der Zellstoffherstellung
US5593544A (en) * 1993-07-12 1997-01-14 Kvaerner Pulping Aktiebolag Pulp production
WO1995013419A1 (en) * 1993-11-08 1995-05-18 Kamyr, Inc. Implementation of dissolved solids profiling
EP1538256A3 (de) * 1993-11-08 2006-01-25 Andritz Inc Verwirklichung des Profils der gelösten Feststoffe
EP1878827A3 (de) * 1993-11-08 2008-06-18 Andritz Inc. Profilierung aufgelöster Feststoffe
EP0822288A3 (de) * 1993-11-08 1998-10-28 Ahlstrom Machinery, Inc. Kontinuierlicher Kocher zur Durchführung von Zellstoffaufschluss mit Kontrolle der gelösten Feststoffe
WO1996006217A1 (en) * 1994-08-18 1996-02-29 Kamyr, Inc. Enhancements in pulping with dissolved solids control
EP0937813A3 (de) * 1994-08-18 1999-09-01 Ahlstrom Machinery, Inc. Verbesserter Holzaufschluss mit Kontrolle der gelösten Feststoffe
WO1996007786A1 (en) * 1994-09-02 1996-03-14 Kamyr, Inc. Continuous kraft cooking with black liquor pretreatment
US6179958B1 (en) 1996-02-09 2001-01-30 Kvaerner Pulping Ab Method for continuous cooking of cellulose-containing fibre material
WO1997029236A1 (en) * 1996-02-09 1997-08-14 Kvaerner Pulping Ab Method for continuous cooking of cellulose-containing fibre material
BE1011503A3 (fr) * 1997-10-17 1999-10-05 Solvay Interox Fabrication de pate a papier chimique.
WO1999020830A1 (fr) * 1997-10-17 1999-04-29 Solvay (Societe Anonyme) Fabrication de pate a papier chimique
WO2002075044A1 (en) * 2001-03-21 2002-09-26 Kvaerner Pulping Ab Continuous digester for cellulose pulp including method and recirculation system for such digester
EP2034090A1 (de) 2007-08-07 2009-03-11 Andritz, Inc. Verfahren und Vorrichtung zum semi-chemischen Aufschliessen
AU2008203206B2 (en) * 2007-08-07 2011-12-15 Andritz Inc. Method and System for Semi-Chemical Pulping
RU2479682C2 (ru) * 2007-08-07 2013-04-20 Андритц Инк. Способ и система для варки полуцеллюлозы
EP3018251A1 (de) * 2014-11-07 2016-05-11 Valmet AB Verfahren zur rückgewinnung von hydrolysat in einem prehydrolysesulfat-kochverfahren für zellstoffherstellung

Also Published As

Publication number Publication date
NO913639D0 (no) 1991-09-16
EP0476230A3 (en) 1993-06-09
FI914353A7 (fi) 1992-03-18
CA2037717C (en) 1996-03-05
NO179918B (no) 1996-09-30
AU7830591A (en) 1992-03-19
NO179918C (no) 1997-01-08
JP3029492B2 (ja) 2000-04-04
RU2089694C1 (ru) 1997-09-10
NO913639L (no) 1992-03-18
DE69123670D1 (de) 1997-01-30
EP0476230B1 (de) 1996-12-18
FI103815B1 (fi) 1999-09-30
FI103815B (fi) 1999-09-30
ATE146538T1 (de) 1997-01-15
BR9103650A (pt) 1992-05-19
JPH04300378A (ja) 1992-10-23
AU647129B2 (en) 1994-03-17
CA2037717A1 (en) 1992-03-18
ZA912117B (en) 1991-11-27
FI914353A0 (fi) 1991-09-17

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