[go: up one dir, main page]

FI981803L - Method for preventing the formation of precipitates - Google Patents

Method for preventing the formation of precipitates Download PDF

Info

Publication number
FI981803L
FI981803L FI981803A FI981803A FI981803L FI 981803 L FI981803 L FI 981803L FI 981803 A FI981803 A FI 981803A FI 981803 A FI981803 A FI 981803A FI 981803 L FI981803 L FI 981803L
Authority
FI
Finland
Prior art keywords
waste liquor
temperature
liquor flow
pulp
fibrous material
Prior art date
Application number
FI981803A
Other languages
Finnish (fi)
Swedish (sv)
Other versions
FI981803A0 (en
FI981803A7 (en
Inventor
Kaj Henricson
Erkki Kiiskilae
Original Assignee
Ahlstrom Machinery Oy
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 Ahlstrom Machinery Oy filed Critical Ahlstrom Machinery Oy
Priority to FI981803A priority Critical patent/FI981803A7/en
Publication of FI981803A0 publication Critical patent/FI981803A0/en
Priority to PCT/FI1999/000689 priority patent/WO2000011263A1/en
Publication of FI981803L publication Critical patent/FI981803L/en
Publication of FI981803A7 publication Critical patent/FI981803A7/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
    • D21C3/00—Pulping cellulose-containing materials
    • D21C3/22—Other features of pulping 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
    • D21C11/00—Regeneration of pulp liquors or effluent waste waters
    • 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
    • D21C11/00—Regeneration of pulp liquors or effluent waste waters
    • D21C11/10—Concentrating spent liquor by evaporation
    • D21C11/106—Prevention of incrustations on heating surfaces during the concentration, e.g. by elimination of the scale-forming substances contained in the liquors

Landscapes

  • Paper (AREA)
  • Removal Of Specific Substances (AREA)
  • Processing Of Solid Wastes (AREA)

Abstract

The present invention relates to a method of preventing scale formation in a pulping process of chemical pulp. The method comprises at least the following steps: a) comminuted cellulosic fibrous material is treated with cooking liquor at a temperature below 120 DEG C, b) a first waste liquor flow containing metals, e.g. calcium, is separated from the material and a waste liquor flow is obtained, the temperature of which is below 120 DEG C, c) fresh cooking liquor is added to the fibrous material, d) fibrous material is degested at a temperature of 140 - 170 DEG C to produce chemical pulp, e) a second waste liquor flow is separated from the pulp and a waste liquor flow is obtained, the temperature of which is over 130 DEG C, f) the first waste liquor flow from step b) is heated to a temperature over 120 DEG C, g) the heated waste liquor flow from step f) is maintained at a temperature over 120 DEG C for at least 0.1 min, preferably 1 - 20 min in order to precipitate metals, especially calcium, present in waste liquor, h) the heat-treated waste liquor flow is passed to further treatment, and i) the pulp from step e) is washed.
FI981803A 1998-08-21 1998-08-21 Method for preventing the formation of precipitates FI981803A7 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
FI981803A FI981803A7 (en) 1998-08-21 1998-08-21 Method for preventing the formation of precipitates
PCT/FI1999/000689 WO2000011263A1 (en) 1998-08-21 1999-08-20 Method of preventing scaling

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
FI981803A FI981803A7 (en) 1998-08-21 1998-08-21 Method for preventing the formation of precipitates

Publications (3)

Publication Number Publication Date
FI981803A0 FI981803A0 (en) 1998-08-21
FI981803L true FI981803L (en) 2000-02-22
FI981803A7 FI981803A7 (en) 2000-02-22

Family

ID=8552343

Family Applications (1)

Application Number Title Priority Date Filing Date
FI981803A FI981803A7 (en) 1998-08-21 1998-08-21 Method for preventing the formation of precipitates

Country Status (2)

Country Link
FI (1) FI981803A7 (en)
WO (1) WO2000011263A1 (en)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FI110327B (en) * 1999-10-04 2002-12-31 Metso Chemical Pulping Oy Process for preparing cellulose pulp
SE0004049L (en) * 2000-11-03 2001-11-05 Kvaerner Pulping Tech Continuous boiling of pulp less used cooking liquor partly from the digester and partly from a subsequent pressure diffuser
US7241363B2 (en) * 2004-06-26 2007-07-10 International Paper Company Methods to decrease scaling in digester systems
PT2753750T (en) * 2011-09-05 2019-06-06 Stora Enso Oyj Process for treating hardwood black liquor and hardwood black liquor treated according to the process
US8986504B1 (en) 2013-10-25 2015-03-24 International Paper Company Digester apparatus

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SE8502807D0 (en) * 1985-06-06 1985-06-06 Ahlstroem Foeretagen SET AND DEVICE DISABLE DEVICE
CA1299322C (en) * 1987-10-26 1992-04-28 Larry A. Wilhelmsen Apparatus and methods for reducing the formation of scale in pulping operations
US5674359A (en) * 1995-02-08 1997-10-07 Ahlstrom Machinery Inc. Continuous cooking of cellulosic fibrous material with cold alkali impregnation
FI972954L (en) * 1997-07-11 1999-01-12 Sunds Defibrator Pori Oy Method for treating waste liquor generated in the production of sulphate pulp

Also Published As

Publication number Publication date
FI981803A0 (en) 1998-08-21
WO2000011263A1 (en) 2000-03-02
FI981803A7 (en) 2000-02-22

Similar Documents

Publication Publication Date Title
CA2098092A1 (en) Method of Treatment of Waste Paper of the Like
FI103899B1 (en) Process for producing extremely pale pulp
WO2004020472A3 (en) Improved process for treating pectin containing plant material
FI981803A0 (en) Method for preventing the formation of precipitates
SE9903344L (en) Cooking of pulp with special alkali profiles
BR9915044A (en) Process for the production of pulp from material containing lignocellulose
ATE472631T1 (en) METHOD FOR CONTINUOUSLY COOKING PULP
NO177607C (en) Process for reducing the amount of organic halogen compounds in backwater
ATE151825T1 (en) METHOD FOR TREATING WASTEWATER
FI973474A0 (en) Foerfarande Foer tillvaratagande av myrsyra
NO920828L (en) PROCEDURE FOR DELIGNIFICATION OF CELLULOSE-SUBSTANCES
DE69121332D1 (en) METHOD FOR PRODUCING POWERS
NO995253L (en) Method of treating an iron sulphate solution
ATE201064T1 (en) METHOD AND DEVICE FOR CONTINUOUS PULP COOKING
SE0000031L (en) Heat treatment of ground, chemically prepared pulp suspension
FI991618A7 (en) Method for preparing pulp
Twimasi The kinetics of the sulphate pulping of Gmelina arborea from Ghana
SE9603518L (en) Process for preparing chemical pulp of disintegrated cellulosic material
SE9000437L (en) WASTE WATER TREATMENT
DE50001600D1 (en) Process for increasing the water retention of paper pulp
PL357525A1 (en) A method for treatment of flue gas cleaning products
TH18059A (en) Method for treating water from the process
JPS59192792A (en) Regeneration of spent paper
SE9800797L (en) Preparation of pulp
SE9602455D0 (en) Method and apparatus for treating pulp