US3451888A - Bleaching pulp having high consistency with ozone having moisture content near 100% - Google Patents

Bleaching pulp having high consistency with ozone having moisture content near 100% Download PDF

Info

Publication number
US3451888A
US3451888A US545919A US3451888DA US3451888A US 3451888 A US3451888 A US 3451888A US 545919 A US545919 A US 545919A US 3451888D A US3451888D A US 3451888DA US 3451888 A US3451888 A US 3451888A
Authority
US
United States
Prior art keywords
ozone
pulp
bleaching
rate
gaseous
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.)
Expired - Lifetime
Application number
US545919A
Other languages
English (en)
Inventor
Bernard Ancelle
Marcel Plancon
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.)
Progil SARL
Original Assignee
Progil SARL
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 Progil SARL filed Critical Progil SARL
Application granted granted Critical
Publication of US3451888A publication Critical patent/US3451888A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

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
    • D21C9/1073—Bleaching ; Apparatus therefor with O3

Definitions

  • the present invention relates to a method of bleaching paper pulp utilizing ozone. More particularly, it relates to the use of wetted ozonized air as a bleaching agent.
  • the process according to the invention comprises passing a gaseous flow, coming from an ozonizer and titrating 2.5 to 18 mg. O /liter, preferably 4 to 16 mg./liter, into a saturator/moistener, then sending it as it escapes from the apparatus at a rate of 50 to 500 liter/hour, preferably 100 to 300 liter/hour Patented June 24, 1969 'ice during a time of /22 /2 hours, preferably 1 to 2 hours, to a shredded paper pulp, with a dryness of 30-65%, having a pH near neutrality and maintained at a temperature of 20 to 30 C.
  • the moisture state of the gaseous flow is an essential element of the process according to the present invention.
  • the ozonized air must have a relative moisture near In any case it is necessary that the moisture content be the highest possible in order to avoid any drying variation of the pulp in treatment and to give to bleaching its efficiency maximum.
  • the ozonized gaseous flow according to the invention may be constituted not only by air, as this is considered during this description, but also by oxygen.
  • Azone titre and gaseous rate may be selected in the present invention field wiht regard to the variables inherent to the used installation without being prejudicial to the obtained result: indeed experiment has shown that the important factor in this field is the weight of used ozone per time unit. For example a fairly similar whiteness will be obtained in carrying out the process during the same time: A gaseous flow at a rate of 300 l./hr., titrating 6.10 mg. 0 /1. (that is 1830 mg. O /hr.); a gaseous flow at a rate of 200 l./hr., titrating 9.30 mg. 0 /1. (that is 1860 mg. O /hr.).
  • Treatment time may vary in the limits of 30 minutes to 2 hours 30 minutes according to the conditions selected in the field in order to give a maximum treatment efiiciency. This may easily be established with regard to the selected gaseous rate and/or ozone titre, so as to obtain the desired bleaching degree. For example, a whiteness, Elrepho of 60 may be obtained:
  • Ozonized air rate (l./hr.) 100 200 300 Ozone titre (in mg./l.):
  • the bleaching method according to the present invention is limited neither by raw material nature nor by the process used for paper pulp fabrication.
  • pulps obtained from wood of resinous or long leaf trees and prepared by soda, sulfite or sulfate process fit quite well to the method according to the invention.
  • Dryness, percent; Elrepho whiteness A eucalyptus kraft pulp, treated at a rate of 200 l./hr. with an ozone concentration of 9.5 mg./l. has the following values:
  • the ozonized air stream saturated with moisture should be at the same temperature as that at which the pulp is maintained during reaction. Moreover, it must be taken care that the cellulosic material does not undergo notable temperature increase during ozonization. For this reason the equipment may possibly be provided with a cooling system.
  • the process according to the present invention offers a great ease in application since it consists of sending ozonized air to paper pulp in an only working stage.
  • the treatment may be made in a discontinuous way, but also in a continuous one, which is interesting for industrial applications. Indeed experiment shows the method according to the invention may be made in a continuous way without residual ozone in the air at the bleaching tower outlet.
  • ozone treatment may be inserted into a bleaching sequence in several stages, ozonization being able to come before or to follow the usual treatments with hydrogen peroxide, hypochlorite or chlorine and soda.
  • EXAMPLE 1 A sample A of 25 g. of pine kraft unbleached pulp having a dryness rate of 40% g. of dry extract) is shredded and put into a glass flask provided with an inlet tube and a gas recovery tube. The pulp has a pH of 7 and is maintained at a temperature of 20 C. An ozonized air stream titrating 15.5 mg./l. ozone is saturated with moisture at 20 C. in a moistener and enters the flask at a rate of l./hr. The treatment is carried on for 2 hours.
  • a second identical sample, B is treated in the same conditions but the ozonized air stream titrates 7.0 mg./l. ozone and is sent to the flask at a rate of 200 l./ hr.
  • EXAMPLE 2 This example illustrates the very clear superiority of the bleaching with moistened ozonized air according to the present invention, with regard to the known process with dry ozonized air.
  • a method in accordance with claim 1 comprising: passing a gaseous mixture of ozone containing 2.5-18 mg. O /liter and having a moisture content near 100%,
  • said gaseous mixture consists essentially of air, water and ozone.

Landscapes

  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Wood Science & Technology (AREA)
  • Selective Calling Equipment (AREA)
  • Paper (AREA)
US545919A 1965-04-30 1966-04-28 Bleaching pulp having high consistency with ozone having moisture content near 100% Expired - Lifetime US3451888A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
FR45940A FR1441787A (fr) 1965-04-30 1965-04-30 Procédé de blanchiment des pâtes à papier

Publications (1)

Publication Number Publication Date
US3451888A true US3451888A (en) 1969-06-24

Family

ID=8598718

Family Applications (1)

Application Number Title Priority Date Filing Date
US545919A Expired - Lifetime US3451888A (en) 1965-04-30 1966-04-28 Bleaching pulp having high consistency with ozone having moisture content near 100%

Country Status (4)

Country Link
US (1) US3451888A (en, 2012)
FR (1) FR1441787A (en, 2012)
NO (1) NO124789B (en, 2012)
SE (1) SE302243B (en, 2012)

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3663357A (en) * 1969-11-27 1972-05-16 Pulp Paper Res Inst Bleaching of mechanical cellulosic pulp with ozone in the presence of a peroxygen compound
JPS5324401A (en) * 1976-08-12 1978-03-07 Seisan Kaihatsu Kagaku Kenkyus Process for multistage pulp bleaching
US4119486A (en) * 1975-08-14 1978-10-10 Westvaco Corporation Process for bleaching wood pulp with ozone in the presence of a cationic surfactant
US4196043A (en) * 1970-12-21 1980-04-01 Scott Paper Company Kraft pulp bleaching and recovery process
US4216054A (en) * 1977-09-26 1980-08-05 Weyerhaeuser Company Low-consistency ozone delignification
US4283251A (en) * 1980-01-24 1981-08-11 Scott Paper Company Ozone effluent bleaching
US4410397A (en) * 1978-04-07 1983-10-18 International Paper Company Delignification and bleaching process and solution for lignocellulosic pulp with peroxide in the presence of metal additives
AT393701B (de) * 1989-12-22 1991-12-10 Schmidding Wilh Gmbh & Co Verfahren zum bleichen von cellulosehaeltigen materialien sowie anlage zur durchfuehrung des verfahrens
US5164044A (en) * 1990-05-17 1992-11-17 Union Camp Patent Holding, Inc. Environmentally improved process for bleaching lignocellulosic materials with ozone
US5164043A (en) * 1990-05-17 1992-11-17 Union Camp Patent Holding, Inc. Environmentally improved process for bleaching lignocellulosic materials with ozone
US5188708A (en) * 1989-02-15 1993-02-23 Union Camp Patent Holding, Inc. Process for high consistency oxygen delignification followed by ozone relignification
US5211811A (en) * 1989-02-15 1993-05-18 Union Camp Patent Holding, Inc. Process for high consistency oxygen delignification of alkaline treated pulp followed by ozone delignification
US5409570A (en) * 1989-02-15 1995-04-25 Union Camp Patent Holding, Inc. Process for ozone bleaching of oxygen delignified pulp while conveying the pulp through a reaction zone
US5441603A (en) * 1990-05-17 1995-08-15 Union Camp Patent Holding, Inc. Method for chelation of pulp prior to ozone delignification
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
US20030131958A1 (en) * 2001-11-30 2003-07-17 Thomas Jaschinski Use of ozone for increasing the wet strength of paper and nonwoven

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2620744A1 (fr) * 1987-09-17 1989-03-24 Degremont Procede de traitement par l'ozone de materiaux ligno-cellulosiques, notamment de pates a papier et reacteur pour la mise en oeuvre de ce procede
US5472572A (en) * 1990-10-26 1995-12-05 Union Camp Patent Holding, Inc. Reactor for bleaching high consistency pulp with ozone
US5181989A (en) * 1990-10-26 1993-01-26 Union Camp Patent Holdings, Inc. Reactor for bleaching high consistency pulp with ozone
US5520783A (en) * 1990-10-26 1996-05-28 Union Camp Patent Holding, Inc. Apparatus for bleaching high consistency pulp with ozone
US5174861A (en) * 1990-10-26 1992-12-29 Union Camp Patent Holdings, Inc. Method of bleaching high consistency pulp with ozone
FI922279L (fi) * 1991-05-24 1992-11-25 Union Camp Patent Holding Tvaostegsreaktor foer blekning av massa

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2466633A (en) * 1948-05-26 1949-04-05 James M Daily Method of bleaching cellulosic pulp

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2466633A (en) * 1948-05-26 1949-04-05 James M Daily Method of bleaching cellulosic pulp

Cited By (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3663357A (en) * 1969-11-27 1972-05-16 Pulp Paper Res Inst Bleaching of mechanical cellulosic pulp with ozone in the presence of a peroxygen compound
US4196043A (en) * 1970-12-21 1980-04-01 Scott Paper Company Kraft pulp bleaching and recovery process
US4119486A (en) * 1975-08-14 1978-10-10 Westvaco Corporation Process for bleaching wood pulp with ozone in the presence of a cationic surfactant
JPS5324401A (en) * 1976-08-12 1978-03-07 Seisan Kaihatsu Kagaku Kenkyus Process for multistage pulp bleaching
US4216054A (en) * 1977-09-26 1980-08-05 Weyerhaeuser Company Low-consistency ozone delignification
US4410397A (en) * 1978-04-07 1983-10-18 International Paper Company Delignification and bleaching process and solution for lignocellulosic pulp with peroxide in the presence of metal additives
US4283251A (en) * 1980-01-24 1981-08-11 Scott Paper Company Ozone effluent bleaching
US5211811A (en) * 1989-02-15 1993-05-18 Union Camp Patent Holding, Inc. Process for high consistency oxygen delignification of alkaline treated pulp followed by ozone delignification
US5409570A (en) * 1989-02-15 1995-04-25 Union Camp Patent Holding, Inc. Process for ozone bleaching of oxygen delignified pulp while conveying the pulp through a reaction zone
US5188708A (en) * 1989-02-15 1993-02-23 Union Camp Patent Holding, Inc. Process for high consistency oxygen delignification followed by ozone relignification
AT393701B (de) * 1989-12-22 1991-12-10 Schmidding Wilh Gmbh & Co Verfahren zum bleichen von cellulosehaeltigen materialien sowie anlage zur durchfuehrung des verfahrens
US5164044A (en) * 1990-05-17 1992-11-17 Union Camp Patent Holding, Inc. Environmentally improved process for bleaching lignocellulosic materials with ozone
US5296099A (en) * 1990-05-17 1994-03-22 Union Camp Holding, Inc. Environmentally improved process for bleaching lignocellulosic materials with oxygen, ozone and chlorine dioxide
US5164043A (en) * 1990-05-17 1992-11-17 Union Camp Patent Holding, Inc. Environmentally improved process for bleaching lignocellulosic materials with ozone
US5441603A (en) * 1990-05-17 1995-08-15 Union Camp Patent Holding, Inc. Method for chelation of pulp prior to ozone delignification
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
US5693184A (en) * 1993-10-01 1997-12-02 Union Camp Patent Holding, Inc. Reduction of salt scale precipitation by control of process stream pH and salt concentration
US20030131958A1 (en) * 2001-11-30 2003-07-17 Thomas Jaschinski Use of ozone for increasing the wet strength of paper and nonwoven

Also Published As

Publication number Publication date
NO124789B (en, 2012) 1972-06-05
FR1441787A (fr) 1966-06-10
SE302243B (en, 2012) 1968-07-08

Similar Documents

Publication Publication Date Title
US3451888A (en) Bleaching pulp having high consistency with ozone having moisture content near 100%
US4080249A (en) Delignification and bleaching of a lignocellulosic pulp slurry with ozone
CN114174589B (zh) 漂白纸浆的制造方法
US3663357A (en) Bleaching of mechanical cellulosic pulp with ozone in the presence of a peroxygen compound
US3806404A (en) Treatment of cellulosic matter with activated nitrogen or other activated gases
US3725194A (en) Treatment of alkaline pulp with an acidic medium followed by oxygen bleaching and delignification
EP0112377A1 (en) Ozone bleaching of cellulosic materials.
CA1152940A (en) Delignification and bleaching of lignocellulosic pulp via photo-oxygenation
US2510595A (en) Method of bleaching groundwood
RU96100538A (ru) Способ отбеливания целлюлозы
US2125634A (en) Method of bleaching pulp or paper webs
JP3447773B2 (ja) リグノセルロースパルプの漂白方法および酸素富化ガスの回収方法
US3655505A (en) Two-stage purification of fibrous cellulose material employing gaseous chlorine dioxide in one stage and a peroxygen compound in the other
YU23892A (sh) Postupak za beljenje hemijske kaše hartije i primena ovog postupka za beljenje kraft kaše
US3177111A (en) Hypochlorite sulfamic acid process of bleaching cellulosic materials
US3284283A (en) Production of wood pulps including treatment of cellulosic fibers with bisulfite ion followed by alkali metal borohydride
US5139613A (en) Process for preparing a paper pulp using carbon dioxide as an acidifying agent for a bleached pulp
US3586599A (en) Purification of fluffed or shredded pulp with chlorine dioxide
US2779656A (en) Bleaching of kraft pulp
US2465738A (en) Method of bleaching mechanical wood fibers
JP3325324B2 (ja) 粗セルロースの脱リグニン化方法
CA1129156A (en) Bleaching stilbene yellow dyed wood pulp
USRE28887E (en) Sequential bleaching of kraft pulp with chlorine dioxide followed by chlorine
RU2046869C1 (ru) Способ получения беленой целлюлозы
US5030324A (en) Sequential bleaching procedure using chlorine and chlorine dioxide in a first chlorination stage of a multistage bleaching process