NO975038L - Treatment of pulp with chelating agent and subsequent bleaching at a pH above 9 - Google Patents

Treatment of pulp with chelating agent and subsequent bleaching at a pH above 9

Info

Publication number
NO975038L
NO975038L NO975038A NO975038A NO975038L NO 975038 L NO975038 L NO 975038L NO 975038 A NO975038 A NO 975038A NO 975038 A NO975038 A NO 975038A NO 975038 L NO975038 L NO 975038L
Authority
NO
Norway
Prior art keywords
pulp
chelating agent
treatment
bleaching
subsequent bleaching
Prior art date
Application number
NO975038A
Other languages
Norwegian (no)
Other versions
NO975038D0 (en
Inventor
Rolf Boman
Ulf Germgaard
Jonas Lindquist
Kenneth Hafvenstroem
Original Assignee
Sunds Defibrator Ind 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 Sunds Defibrator Ind Ab filed Critical Sunds Defibrator Ind Ab
Publication of NO975038L publication Critical patent/NO975038L/en
Publication of NO975038D0 publication Critical patent/NO975038D0/en

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
    • D21C9/10—Bleaching ; Apparatus therefor
    • D21C9/1026—Other features in bleaching processes
    • D21C9/1042—Use of chelating agents
    • 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

Landscapes

  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Wood Science & Technology (AREA)
  • Paper (AREA)

Abstract

Fremgangsmåte for klorfrl bleking av masse av lignocellulosemaleriale, omfattende behandling av massen med chelateringsmiddel og påfølgende bleking i minst ett trinn med klorfrie blekemidler. I henhold til fremgangsmåten holdes pH- verdien over 9 både i chelateringsmiddel-trinnet og i påfølgende bleketrinn.Process for chlorinating bleaching of lignocellulosic pulp, comprising treating the pulp with chelating agent and subsequent bleaching in at least one step with chlorine-free bleaching agents. According to the process, the pH is maintained above 9 in both the chelating agent step and in the subsequent bleaching step.

NO975038A 1995-05-02 1997-10-31 Treatment of pulp with chelating agent and subsequent bleaching at a pH above 9 NO975038D0 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
SE9501623A SE9501623L (en) 1995-05-02 1995-05-02 Bleaching of pulp
PCT/SE1996/000405 WO1996035015A1 (en) 1995-05-02 1996-03-27 TREATMENT OF PULP WITH CHELATING AGENT AND SUBSEQUENT BLEACHING AT A pH VALUE ABOVE 9

Publications (2)

Publication Number Publication Date
NO975038L true NO975038L (en) 1997-10-31
NO975038D0 NO975038D0 (en) 1997-10-31

Family

ID=20398166

Family Applications (1)

Application Number Title Priority Date Filing Date
NO975038A NO975038D0 (en) 1995-05-02 1997-10-31 Treatment of pulp with chelating agent and subsequent bleaching at a pH above 9

Country Status (6)

Country Link
JP (1) JPH11504399A (en)
CA (1) CA2219767A1 (en)
FI (1) FI974115A0 (en)
NO (1) NO975038D0 (en)
SE (1) SE9501623L (en)
WO (1) WO1996035015A1 (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SE509444C2 (en) * 1997-05-14 1999-01-25 Mo Och Domsjoe Ab Procedure for Minimizing Calcium Caused Incrustation Problems in Preparation of Bleached Cellulose Pulp
CA2310278A1 (en) * 1997-11-25 1999-06-03 Amylum Belgium N.V. Improvements to the bleaching process for chemical pulp and intermediate pulp dispersions
BE1011785A3 (en) * 1998-03-10 2000-01-11 Solvay Process for laundering and / or pasta delignification paper chemicals.

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
ES2096441T3 (en) * 1992-11-27 1997-03-01 Eka Chemicals Ab PROCEDURE TO DE-LIGNIFY PASTA CONTAINING LIGNOCELLULOSE.
US5554259A (en) * 1993-10-01 1996-09-10 Union Camp Patent Holdings, Inc. Reduction of salt scale precipitation by control of process stream Ph and salt concentration

Also Published As

Publication number Publication date
CA2219767A1 (en) 1996-11-07
WO1996035015A1 (en) 1996-11-07
FI974115A (en) 1997-11-03
SE9501623D0 (en) 1995-05-02
JPH11504399A (en) 1999-04-20
NO975038D0 (en) 1997-10-31
FI974115A0 (en) 1997-11-03
SE9501623L (en) 1996-11-03

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