EP0207062A1 - Chloration d'une pâte sous pression et introduction du chlore sous forme de bulles minuscules - Google Patents

Chloration d'une pâte sous pression et introduction du chlore sous forme de bulles minuscules Download PDF

Info

Publication number
EP0207062A1
EP0207062A1 EP86890168A EP86890168A EP0207062A1 EP 0207062 A1 EP0207062 A1 EP 0207062A1 EP 86890168 A EP86890168 A EP 86890168A EP 86890168 A EP86890168 A EP 86890168A EP 0207062 A1 EP0207062 A1 EP 0207062A1
Authority
EP
European Patent Office
Prior art keywords
mixer
chlorine gas
slurry
pressure
retention vessel
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
EP86890168A
Other languages
German (de)
English (en)
Other versions
EP0207062B1 (fr
Inventor
Michael I. Sherman
Joseph R. Phillips
Gordon Rowlandson
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
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 Kamyr Inc filed Critical Kamyr Inc
Priority to AT86890168T priority Critical patent/ATE48452T1/de
Publication of EP0207062A1 publication Critical patent/EP0207062A1/fr
Application granted granted Critical
Publication of EP0207062B1 publication Critical patent/EP0207062B1/fr
Expired 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
    • D21C9/12—Bleaching ; Apparatus therefor with halogens or halogen-containing compounds

Definitions

  • chlorine is injected through nozzles into a mixer, and then is passed to a retention vessel which is at approximately atmospheric pressure. During the residence of the pulp in the mixer and the retention vessel the chlorine reacts with impurities and encrustants (such as lignin and bark) in the pulp slurry, to effect desired bleaching or delignification.
  • impurities and encrustants such as lignin and bark
  • a method and apparatus are provided for significantly enhancing the efficiency and efficacy of the treatment of comminuted cellulosic fibrous material slurries with chlorine gas, particularly for the bleaching or delignification of chemical pulps.
  • the pressure within the mixer and/or the retention vessel is increased, such as to the range of about 15-150 psig, the solubility of the chlorine gas increases.
  • the chlorine gas has a tendency to take the form of minute bubbles thus increasing the overall reactivity area, and the network of interlocked fibers at this pressure inhibits the coalescence of gas bubbles.
  • the chlorine gas is introduced into the mixer through porous material discs, such as porous ceramic discs or porous sintered metal discs having a pore size of about 5-175 microns, so that from the time of introduction the chlorine is in the form of minute bubbles.
  • porous material discs such as porous ceramic discs or porous sintered metal discs having a pore size of about 5-175 microns
  • the improvements in solubility of the chlorine gas in the pulp slurry that are achieved according to the present invention result in a number of beneficial effects, including decreased overall chemical consumption, use of more chlorine relative to chlorine dioxide (which is also added during treatment, and which is more costly than chlorine gas), decreased volume of slurry in the retention vessel, treatment to lower Kappa numbers, less chemical wastage, and decreased consumption of bleaching agents in subsequent stages.
  • the present invention it is preferred to intimately mix the chlorine gas with the pulp slurry in a fluidizing mixer, the pulp having a consistency of about 2.5-16%, and preferably about 7-12%, and then pass the slurry through a discharge line into a retention vessel.
  • a throttling valve is utilized to throttle the discharge and thereby increase the pressure within the mixer and maintain it at the range of about 15-150 psig (1 to 10 bar above atmospheric pressure).
  • a similar throttling valve is placed at the discharge of the retention vessel to also maintain the pressure therewithin within the range of 15-150 psig (1 to 10 bar above atmospheric pressure).
  • the chlorine gas when introduced into the mixer is introduced through porous material discs so as to be in the form of minute bubbles.
  • the invention is applicable to a wide variety of procedures for the treatment of comminuted cellulosic fibrous material slurries with chlorine gas.
  • the invention is useful as the first stage of a multistate bleach feed in the bleaching of deciduous wood chemical pulps, coniferous wood chemical pulps, mixtures of chemical pulps, and non-wood fibrous chemical pulps; as the first stage of a delignification procedure as a stage subsequent to an initial delignification using oxygen; and in like bleaching, delignification, and related procedures.
  • Chemical pulp is provided in a conventional bleach feed storage tank 10, the pulp being introduced therein through an inlet 11, and being pumped from the bottom of the tank 10 utilizing a conventional fluidizing centrifugal pump 12, such as the type shown in U.S. Patent 4,435,193.
  • the pulp has a consistency of about 2.5-16%, preferable 3.5-13%, and most preferably about 7-12%.
  • the temperature of the pulp slurry typically will be from 50°F-160°F (10 to 71 °C), more preferably 80-150°F (27 to 66°C).
  • the pulp is pumped in line 13 to conventional fluidizing centrifugal mixer 14.
  • the mixer 14 preferably is capable of fluidizing pulp even if it has a consistency up to about 16%, to effectively intimately mix the pulp with chemicals that are added to it within the mixer.
  • a form such a mixer 16 might take is shown in Canadian Patent 1102604, and such a mixer also is commercially available from Kamyr, Inc. of Glens Falls, New York and sold under the trademark "MC".
  • Chlorine gas from source 15 passes through barometric loop 16' in line 16 and is added to the mixer 14, as is chlorine dioxide from source 17 through line 18.
  • the chlorine'gas will have a temperature of about 75°F-140°F (24 to 60°C), and more commonly in the range of about 90°F-125°F (32 to 52°C).
  • the pressure at source 15 and in line 16 typically will be in the range of about 60-125 psig (4,1 to 8,6 bar above atmospheric pressure) conventional safety devices, valves, and interlocks will be used with the chlorine gas system.
  • Chlorine dioxide from source 17 will typically have a temperature of 35°F-100°F(1,6 to 38°C), more commonly 40°F-55°F (4,4 to 13°C).
  • the chlorine dioxide will be added in liquid form, with concentrations ranging from 4-14 gpl, preferably 6-10 gpl.
  • Total retention time in the pressurized zone - is about 0.01-60 minutes, preferably about 0.1-20 minutes.
  • the invention is particularly applicable to the bleaching of deciduous wood chemical pulps with Kappa numbers in the range of 10-25 (more commonly 15-20), bleaching of coniferous wood chemical pulps with Kappa numbers in the range of 25-150 (more commonly 28-38), bleaching of mixtures of chemical pulps, and bleaching of non-wood fibrous chemical pulps with Kappa numbers in the range of 14-150.
  • the pulp is passed to retention vessel 20 and flows upwardly therein with dilution liquid added through introduction structure 21.
  • the pulp is discharged by a scraper into the discharge line 23 at the top of the retention vessel, and then passes into a stock line and from that preferably into a pressure diffuser or like vessel at the same pressure, for further retention or washing under pressure.
  • the solubility of chlorine in the pulp is significantly increased thus causing more efficient reaction with the impurities in encrustants (such as lignin and bark) on, with, and in the pulp fibers.
  • encrustants such as lignin and bark
  • the application of pressure favors the production of minute bubbles of chlorine gas, and the network of interlocked fibers coupled with the increased pressure inhibits the coalescence of gas bubbles.
  • the end result is decreased overall chemical consumption, decreased degree of substitution of chlorine dioxide for chlorine (chlorine dioxide being more expensive), a decreased volume of slurry in the vessel 20, lower extracted Kappa numbers for the pulp, less chemical wastage, and decreased consumption of bleaching agents in subsequent stages.
  • Pressurization of the mixer 14 and vessel 20 is preferably effected utilizing a valve 30 at the discharge from the mixer 14, and a valve 31 at the discharge 23 from the tank 20.
  • the valves 30, 31 may be selected from a wide variety of available throttling valves, such as valves having all wetted parts of materials resistant to the corrosive-aggressive conditions that are present.
  • the valve 30 may comprise a four inch (100 mm) diameter ball valve
  • the valve 31 may comprise an eight inch (200 mm) diameter ball valve.
  • Typical throttling ball valves that can be utilized in this regard are available from WKM of Houston, Texas, and are sold under the tradename DynaSeal 350.
  • valves 30, 31 are operated, either manually or automatically, to control the pressure within the mixer 14 and/or the tank 20 so that it is within the range of about 15-150 psig (1 to 10 bar above atmospheric pressure) (preferably about 30-120 psig) (2 to 8,3 bar above atmospheric pressure).
  • FIGURE 2 shows the chlorine source 15 connected through line 16 to the mixer 14.
  • the particular interconnection structures illustrated in FIGURE 2 include the branched connection 40 which has branch conduits 41,42 extending therefrom.
  • branch conduit In each branch conduit is disposed a filter 44 and one or more valves 45, and each branch conduit terminates in a chlorine gas injecting nozzle 47.
  • Two such structures are utilized in case one malfunctions (in which case it can be closed off and the other utilized until repair is effected), and also to evenly introduce the chlorine gas into the mixer.
  • the injection nozzles 47 (any reasonable number of nozzles may be provided) in the embodiment illustrated in FIGURE 2 are connected to the mixer 14 at opposite sides of the circular cross-section pulp inlet portion 50 of the mixer.
  • a typical filter 44 is illustrated in FIGURE 3, and includes the solid annular metal body 52 which mounts a circular disc 53 of porous material.
  • Typical porous material for the disc 53 include porous ceramics and sintered metals.
  • a typical chlorine gas injection nozzle 47 is illustrated in FIGURES 4 and 5 and includes a metal housing including annular flange 55 and annular body 56, with a conical surface 57 formed at the innermost end of the body 56 (the end closest to, or extending into, the mixer 14). Disposed within the body 56 and having a conical surface abutting the conical surface 57 is disc 58.
  • the disc 58 comprises means for introducing the chlorine gas in the form of minute bubbles, and comprises a porous material having pore sizes ranging from about 5-175 microns.
  • Typical porous materials utilizable for the formation of the disc 50 are conventionally available porous ceramics and porous sintered metals.
  • the disc 58 is held in place against the conical surface 57 by the gasket 59, locking ring 60, and locking clip 61.
  • the locking ring 60 can be screw- threaded into engagement with the body portion 56 (which has internal threads therein), with the clip 61 engaging the body 56 and the ring 60 to hold them in the position illustrated in FIGURE 4 wherein the ring 60 presses against the gasket 59 and the disc 58.
EP86890168A 1985-06-14 1986-06-06 Chloration d'une pâte sous pression et introduction du chlore sous forme de bulles minuscules Expired EP0207062B1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT86890168T ATE48452T1 (de) 1985-06-14 1986-06-06 Chlorierung von pulpe unter druck und einleitung von chlor in blaeschen.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US74467885A 1985-06-14 1985-06-14
US744678 1985-06-14

Publications (2)

Publication Number Publication Date
EP0207062A1 true EP0207062A1 (fr) 1986-12-30
EP0207062B1 EP0207062B1 (fr) 1989-12-06

Family

ID=24993592

Family Applications (1)

Application Number Title Priority Date Filing Date
EP86890168A Expired EP0207062B1 (fr) 1985-06-14 1986-06-06 Chloration d'une pâte sous pression et introduction du chlore sous forme de bulles minuscules

Country Status (9)

Country Link
EP (1) EP0207062B1 (fr)
JP (1) JPS61289192A (fr)
AT (1) ATE48452T1 (fr)
BR (1) BR8602738A (fr)
CA (1) CA1276408C (fr)
DE (1) DE3667310D1 (fr)
FI (1) FI85728C (fr)
NO (1) NO168123C (fr)
SE (1) SE466459B (fr)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US56833A (en) * 1866-07-31 Improvement in bleaching paper-stock
US1971241A (en) * 1933-04-01 1934-08-21 Pennsylvania Salt Mfg Co Method of chlorination
DE1621684A1 (de) * 1967-10-04 1971-07-08 Bellmer Geb Kg Maschf Maschinenkombination fuer die Leitungsstrecke in Zellstoffaufbereitungsanlagen
FR2227388A1 (en) * 1973-04-27 1974-11-22 Mo Och Domsjoe Ab Bleach tower for wood cellulose slurry - having a device to maintain a pressure difference between the bleach inlet and outlet

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US56833A (en) * 1866-07-31 Improvement in bleaching paper-stock
US1971241A (en) * 1933-04-01 1934-08-21 Pennsylvania Salt Mfg Co Method of chlorination
DE1621684A1 (de) * 1967-10-04 1971-07-08 Bellmer Geb Kg Maschf Maschinenkombination fuer die Leitungsstrecke in Zellstoffaufbereitungsanlagen
FR2227388A1 (en) * 1973-04-27 1974-11-22 Mo Och Domsjoe Ab Bleach tower for wood cellulose slurry - having a device to maintain a pressure difference between the bleach inlet and outlet

Non-Patent Citations (7)

* Cited by examiner, † Cited by third party
Title
ABSTRACT BULLETIN OF THE INSTITUTE OF PAPER CHEMISTRY, vol. 53, no. 2, August 1982, pages 173,174, abstract no. 1392, Appleton, Wisconsin, US; PULP & PAPER: "Ball valves give reliable service in digester blowline application", & PULP PAPER 55, no. 13: 87-88 (Dec. 1981) *
ABSTRACT BULLETIN OF THE INSTITUTE OF PAPER CHEMISTRY, vol. 55, no. 4, October 1984, page 461, abstract no. 4340, Appleton, Wisconsin, US; G.W. PATTYSON: "Kamyr MC (Medium-Consistency) mixer for chlorine dioxide mixing at Great Lakes forest products, Thunder Bay, Ontario", & CPPA ANN. MTG. (MONTREAL) PREPRINTS 70A: 63-68 (Jan. 31-Feb. 1, 1984) *
ABSTRACT BULLETIN OF THE INSTITUTE OF PAPER CHEMISTRY, vol. 56, no. 3, September 1985, page 366, abstract no. 3205, Appleton, Wisconsin, US; D.W. REEVE et al.: "Chlorine gas dispersion optimizes chlorination and reduces corrosion", & PULP PAPER 59, no. 3: 172-175 (March 1985) *
F.A. HENGLEIN: "Grundriss der chemischen Technik", 11th edition, 1963, pages 43,44,126-128, Verlag Chemie GmbH, Weinheim, DE *
TAPPI JOURNAL, vol. 67, no. 5, May 1984, pages 114-117, Atlanta, Georgia, US; A.H.J. PATERSON et al.: "Fundamentals of mixing in pulp suspensions: diffusion of reacting chlorine" *
TAPPI, vol. 59, no. 11, November 1976, pages 106-109, Atlanta, Georgia, US; J. GULLICHSEN: "Medium-consistency chlorination" *
TAPPI, vol. 64, no. 9, September 1981, pages 113-116, Atlanta, Georgia, US; J. GULLICHSEN et al.: "Medium-consistency technology. II. Storage dischargers and centrifugal pumps" *

Also Published As

Publication number Publication date
JPS61289192A (ja) 1986-12-19
EP0207062B1 (fr) 1989-12-06
ATE48452T1 (de) 1989-12-15
SE466459B (sv) 1992-02-17
NO168123B (no) 1991-10-07
CA1276408C (fr) 1990-11-20
FI862082A (fi) 1986-12-15
SE8602592L (sv) 1986-12-15
NO168123C (no) 1992-01-15
SE8602592D0 (sv) 1986-06-10
DE3667310D1 (de) 1990-01-11
FI862082A0 (fi) 1986-05-19
FI85728B (fi) 1992-02-14
FI85728C (fi) 1992-05-25
BR8602738A (pt) 1987-02-10
NO862116L (no) 1986-12-15

Similar Documents

Publication Publication Date Title
US5411633A (en) Medium consistency pulp ozone bleaching
US8168041B2 (en) Device for diluting shredded cellulosic particles/chips
HU205175B (en) Method for chlorie-free bleaching celluloses
EP0078129A1 (fr) Méthode et appareil pour la délignification continue à l'oxygène de matières fibreuses
CA1327102C (fr) Procede pour le blanchiment de la cellulose ou d'une fraction de celle-ci, usine pour ce procede et presse a vis adaptee plus particulierement a ce procede et a cette usine
EP0577157B1 (fr) Procédé de blanchiment au peroxyde
US20080202717A1 (en) Arrangement for Feeding a Slurry of Chips and Liquid
US5372679A (en) Reactor system for treating cellulosic pulp at a constant upward flow velocity
JP4330074B2 (ja) セルロースチップを高圧連続蒸解システムに供給する方法とシステム
US5217575A (en) Process for oxygen bleaching using two vertical reactors
US4288288A (en) Apparatus for mixing chemicals into pulp at a refiner inlet
CA1276408C (fr) Chloration sous pression de la pate papetiere, et injection du chlore en forme de minibulles
JPH0639755B2 (ja) ソウダストからパルプを製造する装置及びソウダストの処理方法
JPS59144692A (ja) 木材パルプの改良漂白法
CA1269502A (fr) Methode pour melanger l'oxygene gazeux a une pate de consistance moyenne dans la decharge d'une pompe
US4022654A (en) Countercurrently bleaching high consistency cellulose pulp with oxygen
US20060169429A1 (en) System and method for oxygen delignification of pulp made for lignocellulosic material
CA2067844A1 (fr) Procede de blanchiment de materiau cellulosique et installation pour mettre en oeuvre ledit procede
US5766414A (en) Method of bleaching cellulose pulp with peroxide under elevated pressure in a first vessel and atmospheric pressure in second vessel
EP0445144A1 (fr) Appareil pour le traitement continu de pate de cellulose
SE452896B (sv) Forfarande for behandling av cellulosamassor
CA2132057A1 (fr) Blanchiment au peroxyde sous pression
SK281290B6 (sk) Spôsob bielenia buničiny bez použitia chlóru
JPH0376883A (ja) セルロースパルプの酸素脱リグニン漂白方法
EP0840820A1 (fr) Procede et equipement de blanchiment de pate a papier au moyen d'un reactif de blanchiment gazeux

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT DE FR

17P Request for examination filed

Effective date: 19870619

17Q First examination report despatched

Effective date: 19880722

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): AT DE FR

REF Corresponds to:

Ref document number: 48452

Country of ref document: AT

Date of ref document: 19891215

Kind code of ref document: T

REF Corresponds to:

Ref document number: 3667310

Country of ref document: DE

Date of ref document: 19900111

ET Fr: translation filed
PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 19950607

Year of fee payment: 10

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 19950609

Year of fee payment: 10

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: AT

Payment date: 19950613

Year of fee payment: 10

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: AT

Effective date: 19960606

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Effective date: 19970228

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Effective date: 19970301

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST