EP0492039A1 - Pneumatischer Reaktor zum Ozonbleichen von Zellstoff - Google Patents
Pneumatischer Reaktor zum Ozonbleichen von Zellstoff Download PDFInfo
- Publication number
- EP0492039A1 EP0492039A1 EP91109775A EP91109775A EP0492039A1 EP 0492039 A1 EP0492039 A1 EP 0492039A1 EP 91109775 A EP91109775 A EP 91109775A EP 91109775 A EP91109775 A EP 91109775A EP 0492039 A1 EP0492039 A1 EP 0492039A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- gas
- ozone
- discharge
- pulp
- recited
- 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.)
- Withdrawn
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
-
- 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
Definitions
- a method for delignifying comminuted cellulosic fibrous material with ozone containing gas comprises the steps of continuously and sequentially: (a) Fluffing the material. (b) Adding a gas, containing an effective amount of ozone to effect delignification, to the material. (c) Pneumatically conveying the material in a first path for at least a few seconds, the ozone reacting with the material during conveyance to effect delignification. (d) Separating the majority of gas from the material at the end of the first path. And, (e) maintaining the material in a generally static state for at least a few seconds.
- the pulp In the fluffer discharge 17 the pulp is entrained in a stream of gas exiting from the gas moving means (blower) 20, and the mixture of ozone containing gas and pulp is thereby pneumatically conveyed in a first path, defined by conduit 21.
- the length of the path defined by conduit 21, and the speed of pneumatic conveyance, are gauged so that the pulp is exposed to the ozone containing gas for at least a few seconds, typically about 15 seconds or less, e.g. about four seconds. Since the pulp in the conduit 21 is fluffy, having a great surface area, and in view of the fact that it is intimately surrounded by the ozone containing gas, being thoroughly mixed therewith without any mechanical elements during the conveyance, the delignifying reaction will be quick and effective.
- a gas/pulp separator -- such as the cyclone 22 -- is provided, the cyclone 22 having a gas discharge 23 and a pulp discharge 24.
- the cyclone 22 allows the charge of ozone to be "slipped", that is it ensures that ozone is not exposed in relatively high concentration to the pulp for such a long period of time that some of the pulp cellulose might be attacked by the ozone.
- the vast majority of the spent gas -- which includes oxygen and unreacted ozone as the primary constituents -- is discharged in conduit 23 for exhaust or recycle, while the comminuted cellulosic fibrous material -- which has little -- though some -- gas remaining therein is discharged at 24.
- a portion of the recycled gas is reused as carrier gas through line 34 into line 35. The remaining portion of recycle gas (nearly equal to supply gas) is recycled to an ozone generation, or if not economical for ozone generation it is exhausted.
- the discharge 24 from cyclone 22 is preferably into a vessel, such as a substantially vertical axis retention tube 25.
- a vessel such as a substantially vertical axis retention tube 25.
- the fluffed pulp is maintained in a generally static condition (although there is movement downwardly in the tube) for at least a few seconds, e.g. for about ten seconds (but typically less than a minute), so that a delignifying reaction with a small amount of residual ozone has an opportunity to move toward completion.
- the pulp is discharged by air lock 26 into another sequence of equipment substantially identical to that just described.
- the air lock 26 preferably is a conventional low pressure feeder, such as used commonly in the pulp and paper art for feeding wood chips to a low pressure steaming vessel.
- any number of sequences of equipment as illustrated in FIGURE 1 can be provided.
- a third set of equipment may be provided, which is illustrated in FIGURE 1 by the same reference numerals as for the first set of equipment only preceded by a "2". That is the fluffed material is discharged from air lock 126 into conduit 221 and pneumatically conveyed therein by the blower 220.
- Ozone containing gas (typically oxygen) from source 18 is provided to the blower 220 to provide a portion of the gas needed to pneumatically convey the fluffed pulp to the third separator 222.
- the majority of the conveying gas is spent gas from line 21 which is passed through line 34 to line 35.
- Fresh ozone/oxygen mixture is added to line 35.
- the gas from gas discharge 223 to the third separator 222 is fed back as the feed gas to the blower 120 and includes ozone therein, while the material is discharged from cyclone 222 to retention tube 225 and then into air lock 226.
Landscapes
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Wood Science & Technology (AREA)
- Paper (AREA)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US63334790A | 1990-12-27 | 1990-12-27 | |
US633347 | 1990-12-27 |
Publications (1)
Publication Number | Publication Date |
---|---|
EP0492039A1 true EP0492039A1 (de) | 1992-07-01 |
Family
ID=24539279
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP91109775A Withdrawn EP0492039A1 (de) | 1990-12-27 | 1991-06-14 | Pneumatischer Reaktor zum Ozonbleichen von Zellstoff |
Country Status (8)
Country | Link |
---|---|
EP (1) | EP0492039A1 (de) |
JP (1) | JPH04245989A (de) |
AU (1) | AU636766B2 (de) |
BR (1) | BR9104366A (de) |
CA (1) | CA2044907A1 (de) |
FI (1) | FI915947A (de) |
NO (1) | NO914169L (de) |
ZA (1) | ZA915144B (de) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO1993014860A1 (en) * | 1992-01-23 | 1993-08-05 | Kamyr Ab | Separation device and process |
US5520783A (en) * | 1990-10-26 | 1996-05-28 | Union Camp Patent Holding, Inc. | Apparatus for bleaching high consistency pulp with ozone |
WO1997005327A1 (en) * | 1995-07-26 | 1997-02-13 | Beloit Technologies, Inc. | Method and apparatus for bleaching pulp with a gaseous bleaching reagent |
US5942088A (en) * | 1995-07-26 | 1999-08-24 | Beloit Technologies, Inc. | Apparatus for bleaching high consistency pulp with a gaseous bleaching reagent |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CA2046717A1 (en) * | 1991-02-06 | 1992-08-07 | Beloit Technologies, Inc. | Method and apparatus for treating fibrous materials with a gaseous reagent |
FI922279A (fi) * | 1991-05-24 | 1992-11-25 | Union Camp Patent Holding | Tvaostegsreaktor foer blekning av massa |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2388933A1 (fr) * | 1977-04-27 | 1978-11-24 | Myrens Verksted As | Procede et installation pour le traitement d'une matiere volumineuse finement divisee notamment d'une pate fibreuse ou cellulosique |
EP0308314A1 (de) * | 1987-09-17 | 1989-03-22 | "DEGREMONT" Société dite: | Verfahren zur Ozonbehandlung von Lignocellulosematerialien, insbesondere Papiermassen, und Reaktor zum Ausführen des Verfahrens |
DE4025616A1 (de) * | 1989-08-16 | 1991-02-21 | Andritz Ag Maschf | Verfahren zur zerkleinerung von materialien und anlage zu dessen durchfuehrung |
Family Cites Families (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3814664A (en) * | 1972-09-11 | 1974-06-04 | Improved Machinery Inc | Gaseous reaction apparatus including a peripheral gas receiving chamber |
-
1991
- 1991-06-14 EP EP91109775A patent/EP0492039A1/de not_active Withdrawn
- 1991-06-18 AU AU79116/91A patent/AU636766B2/en not_active Ceased
- 1991-06-18 CA CA002044907A patent/CA2044907A1/en not_active Abandoned
- 1991-07-03 ZA ZA915144A patent/ZA915144B/xx unknown
- 1991-09-24 JP JP3243410A patent/JPH04245989A/ja not_active Withdrawn
- 1991-10-09 BR BR919104366A patent/BR9104366A/pt not_active Application Discontinuation
- 1991-10-23 NO NO91914169A patent/NO914169L/no unknown
- 1991-12-18 FI FI915947A patent/FI915947A/fi unknown
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2388933A1 (fr) * | 1977-04-27 | 1978-11-24 | Myrens Verksted As | Procede et installation pour le traitement d'une matiere volumineuse finement divisee notamment d'une pate fibreuse ou cellulosique |
EP0308314A1 (de) * | 1987-09-17 | 1989-03-22 | "DEGREMONT" Société dite: | Verfahren zur Ozonbehandlung von Lignocellulosematerialien, insbesondere Papiermassen, und Reaktor zum Ausführen des Verfahrens |
DE4025616A1 (de) * | 1989-08-16 | 1991-02-21 | Andritz Ag Maschf | Verfahren zur zerkleinerung von materialien und anlage zu dessen durchfuehrung |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5520783A (en) * | 1990-10-26 | 1996-05-28 | Union Camp Patent Holding, Inc. | Apparatus for bleaching high consistency pulp with ozone |
WO1993014860A1 (en) * | 1992-01-23 | 1993-08-05 | Kamyr Ab | Separation device and process |
US6004364A (en) * | 1992-01-23 | 1999-12-21 | Kamyr Aktiebolag | Separation device |
WO1997005327A1 (en) * | 1995-07-26 | 1997-02-13 | Beloit Technologies, Inc. | Method and apparatus for bleaching pulp with a gaseous bleaching reagent |
US5942088A (en) * | 1995-07-26 | 1999-08-24 | Beloit Technologies, Inc. | Apparatus for bleaching high consistency pulp with a gaseous bleaching reagent |
Also Published As
Publication number | Publication date |
---|---|
FI915947A0 (fi) | 1991-12-18 |
NO914169L (no) | 1992-06-29 |
NO914169D0 (no) | 1991-10-23 |
AU7911691A (en) | 1992-07-02 |
CA2044907A1 (en) | 1992-06-28 |
AU636766B2 (en) | 1993-05-06 |
JPH04245989A (ja) | 1992-09-02 |
ZA915144B (en) | 1992-05-27 |
BR9104366A (pt) | 1992-08-18 |
FI915947A (fi) | 1992-06-28 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
EP0483163B1 (de) | Umweltfreundlicheres verfahren zum bleichen von lignocellulosischen materialien | |
EP0397308B1 (de) | Verfahren zum Bleichen von Zellstoff mit Ozon | |
EP0591264B1 (de) | Bleichverfahren mittels ozone | |
US5387317A (en) | Oxygen/ozone/peracetic aicd delignification and bleaching of cellulosic pulps | |
US5211811A (en) | Process for high consistency oxygen delignification of alkaline treated pulp followed by ozone delignification | |
EP0492039A1 (de) | Pneumatischer Reaktor zum Ozonbleichen von Zellstoff | |
CA2202714C (en) | Process for increasing the degree of whiteness of paper fiber pulp | |
EP0511433B1 (de) | Ozonbleichen von Zellstoff mittlerer Konsistenz | |
CA1164704A (en) | Method for improving the washing of cellulose pulps | |
RU95122814A (ru) | Способ производства целлюлозы без применения хлорных химикатов | |
EP0492040A1 (de) | Drehender Ozonreaktor für Zellstoff | |
JPH08509781A (ja) | 塩素を含まない薬品によるパルプ漂白法 | |
EP0588704B1 (de) | Rückgewinnung von sauerstoffreichem Gas aus Bleichverfahren mittels Ozon | |
US5733412A (en) | Decolorizing brown fibers in recycled pulp | |
EP0644965B1 (de) | Bleichen von wiederverwendetem zellstoff mittels ozone und wasserstoffperoxyd | |
JP2934512B2 (ja) | セルロース質繊維材料のパルプの漂白方法 | |
US3579419A (en) | Treatment of fluffed pulp fibers with gaseous chlorine | |
WO1995006772A1 (en) | Improved method for bleaching lignocellulosic pulp | |
AU605913B2 (en) | A method in the activation of lignocellulosic material with a gas containing nitrogen dioxide | |
KR930010534B1 (ko) | 펄프의 잉크 제거 및 표백 방법 | |
CA2376528A1 (en) | Bleaching pulp with high-pressure o2 | |
US6231718B1 (en) | Two phase ozone and oxygen pulp treatment | |
CA1186106A (en) | Process and apparatus for the oxygen delignification of pulp | |
CA1195811A (en) | Alkaline-oxygen delignification of cellulose pulp at atmospheric pressure | |
WO1991000386A1 (en) | A method for bleaching kraft pulp with a mixture of oxygen and peroxide |
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 GB IT SE |
|
17P | Request for examination filed |
Effective date: 19921005 |
|
17Q | First examination report despatched |
Effective date: 19930622 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN |
|
18D | Application deemed to be withdrawn |
Effective date: 19970103 |