EP0327469B1 - Verfahren zum Zermahlen lignocelluloseartiger Materialien - Google Patents

Verfahren zum Zermahlen lignocelluloseartiger Materialien Download PDF

Info

Publication number
EP0327469B1
EP0327469B1 EP89400319A EP89400319A EP0327469B1 EP 0327469 B1 EP0327469 B1 EP 0327469B1 EP 89400319 A EP89400319 A EP 89400319A EP 89400319 A EP89400319 A EP 89400319A EP 0327469 B1 EP0327469 B1 EP 0327469B1
Authority
EP
European Patent Office
Prior art keywords
machine
hammer mill
fibers
grading
defibration
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
EP89400319A
Other languages
English (en)
French (fr)
Other versions
EP0327469A1 (de
Inventor
Jean Paul Delaroche
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.)
Beghin Say SA
Original Assignee
Beghin Say SA
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 Beghin Say SA filed Critical Beghin Say SA
Priority to AT89400319T priority Critical patent/ATE74980T1/de
Publication of EP0327469A1 publication Critical patent/EP0327469A1/de
Application granted granted Critical
Publication of EP0327469B1 publication Critical patent/EP0327469B1/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21D—TREATMENT OF THE MATERIALS BEFORE PASSING TO THE PAPER-MAKING MACHINE
    • D21D1/00—Methods of beating or refining; Beaters of the Hollander type
    • D21D1/20—Methods of refining
    • D21D1/32—Hammer mills
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21B—FIBROUS RAW MATERIALS OR THEIR MECHANICAL TREATMENT
    • D21B1/00—Fibrous raw materials or their mechanical treatment
    • D21B1/02—Pretreatment of the raw materials by chemical or physical means
    • D21B1/021—Pretreatment of the raw materials by chemical or physical means by chemical means
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21B—FIBROUS RAW MATERIALS OR THEIR MECHANICAL TREATMENT
    • D21B1/00—Fibrous raw materials or their mechanical treatment
    • D21B1/04—Fibrous raw materials or their mechanical treatment by dividing raw materials into small particles, e.g. fibres
    • D21B1/12—Fibrous raw materials or their mechanical treatment by dividing raw materials into small particles, e.g. fibres by wet methods, by the use of steam
    • D21B1/14—Disintegrating in mills

Definitions

  • the invention relates to a process for defibrating a cellulosic material which has undergone an impregnation pretreatment aimed at softening the lignin, with a view to obtaining a paper pulp.
  • the wood can be disaggregated purely mechanically by means of grinders. This produces high-performance mechanical pulps because most of the constituents of wood are found.
  • This separation can also be obtained by elimination of lignin, which ensures the adhesion of the fibers to each other, by means of chemical reagents.
  • the shavings By subjecting the shavings to cooking for a certain period of time in apparatuses called digesters - with a continuous or discontinuous principle - in the presence of an appropriate reagent, the lignin and other soluble constituents are completely dissolved so as to retain only the cellulose whose fibers are perfectly insulated, the disintegration of chemical pulp is obtained by simple blowing.
  • the platelets are softened by the action of a chemical reagent or water vapor at high temperature, and so-called mechanical chemical, thermo-mechanical or chemico-thermo-mechanical pastes are obtained. .
  • Mechanical processing is generally carried out by disc refiners or the like which are used to individualize the fibers. Depending on the operating conditions, the disc refiners also allow the release of fibrils which will improve the mechanical resistance of the paper obtained.
  • the invention relates to a method for mechanically treating fibrous materials resulting from an impregnation pretreatment, in particular with a chemical agent, promoting the softening of lignin.
  • a process for preparing a paper pulp from wood chips consisting in pretreating said wood chips in a machine of the twin-screw type where they are subjected to a succession of compressions / releases with injection of one or more solutions of at least one chemical agent and then to defibrate the material from the machine by mechanical means, characterized in that after defibering the material is subjected to a classification operation, and in that the classification rejections are subjected to defibration in an apparatus of the hammer mill type.
  • the crusher advantageously replaces the disc refiners, for example, commonly used in this case.
  • FIG. 1 schematically represents part of an installation for producing high-yield cardboard pulp.
  • the arrows in bold line indicate the material flows.
  • It includes a machine of the twin-screw type (1) supplied with wooden chips by a hopper (3) whose capacity is determined to guarantee a satisfactory supply, even in the event of a short-term interruption of the chain for handling the machine.
  • the recovery of the plates under the hopper is carried out by a twin-screw extractor (5) whose speed of rotation is controlled by that of the twin-screw machine to provide it with a supply suitable for all operating modes.
  • the machine rotors are themselves driven by a motor (7).
  • Holes (9) are provided along the envelope of the twin-screw machine to allow the injection of a chemical reagent - which in this case is a solution of neutral sulfite of sodium hydroxide - inside the different treatment pregnant.
  • orifices (11) are provided for injecting the quantity of water necessary for controlling the dryness of the material being treated. Downstream, the machine opens into an outlet chute (13) whose shape allows the distribution of the material flow towards the inlet of two hammer mills (20).
  • the defibration operation in hammer mills requires a supply of water at (22) to reduce the dryness of the material.
  • the raw pulp from the crushers falls into a vat (30) where it is stirred and taken up by a pump (32) to be directed to a battery of binders, two in this case (40,42), arranged in series.
  • the classification rejects are subjected to grinding in a third hammer mill (50) of the same type as the previous ones, also supplied with make-up water in (52) for the control of the dryness of the material which after grinding is recycled to the raw dough tank (30) through the conduit (56).
  • the accepted dough leaves the classification in (44) towards the suction of dough pumps to undergo various subsequent treatments before being accepted in the stock of pulp of the cardboard machine. It is thus, in a manner known per se, purified, for example by passage through cyclone depurator groups arranged in cascade, then directed onto thickeners making it possible to adjust its dryness to the value required for its passage through the cardboard machine.
  • FIG. 2 illustrates a model of hammer mills capable of being used in the process according to the invention.
  • Each rotor consists of parallel discs (210) separated by spacers (only one disc per rotor is visible in the figure). They are connected at their periphery by pins (214) parallel to the shaft.
  • One spindle in two carries a row of parallelepiped hammers (216) oriented radially along their major axis (only one per row is visible in the figure). The hammers have a certain degree of freedom of rotation around their support axis.
  • each rotor is thus provided with four rows of hammers.
  • each rotor On either side of the vertical plane passing through the shaft of each rotor are disposed a central harrow (220) and a lateral harrow (222) whose teeth are interposed between the planes of rotation of the hammers, and extend substantially to the periphery of the discs.
  • a grid (230) in the form of a half cylinder longitudinally covers part of the lower half of each rotor (200) at a short distance from the surface swept by the free ends of the hammers. In this way the hammers cooperate with the peripheral grid to break and defibrate the material remaining in the device.
  • Each grid is pierced with calibrated orifices (holes or slits) so as to allow the passage of individualized fibers while retaining the maximum of logs. The fibers having passed through the grid are entrained towards the outlet opening (208).
  • the calibration of these orifices is decisive for obtaining the expected result. It is desirable that the diameter of the holes be between 1 and 5 mm, or when it is a slot that their width is between 0.4 and 2 mm. When the shape of the orifices is not cylindrical, these values apply to their smallest transverse dimension.
  • Nozzles (240) for injecting water are disposed across the intake opening (206).
  • Sheets (250) extend the cylindrical grids (230) to confine the enclosure swept by the rotor and limit projections. They are articulated around a longitudinal axis to give access to the rotor when maintenance is required.
  • the plates are prepared before their admission into the hopper (3) they are sieved so that only those which have the appropriate dimensions are accepted, washed and free of all foreign matter.
  • This machine consists, in accordance with the teaching of patent FR 2,418,295, of two parallel screws whose threads are identical and which are driven in the same direction of rotation inside a sheath.
  • the threads consist of successive zones with different pitches.
  • the threading is first of all direct pitch for driving the material downstream, then the pitch is reversed to brake the material until it forms a plug.
  • the material passes in a second section to the other through calibrated windows, formed in the thread immediately downstream of the plug area, undergoing relaxation.
  • the size of the windows is chosen so as not to reduce the length of the fibers but to simply split the plates.
  • the machine thus comprises a certain number of sections which follow one another from upstream to downstream.
  • the material goes through a series of alternating phases of pressure build-ups followed by pressure drops which allow the material to be impregnated with the desired reagent.
  • the excess liquid released during the compression phases can possibly be eliminated by filters placed in suitable places.
  • Controlled quantities of water are introduced inside the different sections so that the advancement of the material occurs under optimal conditions.
  • the product produced by the machine comes out with a dryness of 25 to 30%.
  • the material is only partially defibrated. Under the operating conditions of the exemplary embodiment presently illustrated, the rate of sticks is 55%.
  • the material Upon entering the mill, the material is sprayed with water by means of the nozzles so that at the outlet its dryness is reduced to a value between 2 and 20%.
  • the adjustment of the dryness allows an adjustment of the treatment in relation to the rate of sticks and to the classification BAUER MAC NETT.
  • long fibers is meant the proportion of fibers which are collected through a 28 MESH sieve. This result should be compared to that of a mechanical grinding wheel pulp for which the proportion of fibers collected through a 28 MESH sieve is 22%.
  • Another advantage of using a hammer mill under these conditions is the significant gain in energy achieved compared to defibering carried out in conventional refiners which, moreover, at an equivalent degree of refining, do not allow the conservation of such a high proportion of long fibers.
  • the same amount of wood was subjected to four different treatments, the first treatment A corresponding to that of the invention where the wafers were impregnated with neutral sulfite of sodium in a twin-screw machine then defibrated in a grinder of the type described above, the grid of which is pierced with holes of 2.5 mm in diameter.
  • a second treatment B the same raw paste leaving a twin-screw pretreatment is passed through two refiners in series of the DEFIBRATOR and BAUER 411 type to obtain a paste having the same degree of drainage.
  • a chip paste is passed through the same refiners.
  • the treatment recommended by the invention produces a pulp whose proportion of long fibers collected in the T28 sieve is 54.4%, that is to say more than 10% greater than that obtained in conventional refiners with a proportion of fines less than 20%, this for equivalent degrees of drainage.
  • the raw dough from the crusher whose dryness fell for example to 2%, only has a rate of sticks of the around 15%.
  • the dough is collected in a vat room with classification rejects where it undergoes continuous brewing. At the exit of the vat, the dough is pumped towards the battery of binders which will eliminate the sticks.
  • the dough accepted by the classification contains only about 0.6% of sticks and can be subjected to conventional operations of purification and thickening before delivery to the stock machine.
  • the classification rejects are subjected to grinding in a hammer mill (50) similar to the first two (20), an addition of water (32) reduces the dryness of the dough which is returned to the vat (30).
  • the process which has just been described has the advantage of producing a high-yield pulp whose fiber length is kept to the maximum with a reduced energy expenditure. It is obvious that the hammer mills can be fed with other raw doughs than those resulting from a pretreatment with a twin-screw machine as long as this dough has sufficient impregnation to the core for optimal use in the shredders.
  • the installation may include a combination of conventional refiners and hammer mills if necessary.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Wood Science & Technology (AREA)
  • Paper (AREA)
  • Treatments For Attaching Organic Compounds To Fibrous Goods (AREA)
  • Seasonings (AREA)
  • Polysaccharides And Polysaccharide Derivatives (AREA)
  • Disintegrating Or Milling (AREA)
  • Developing Agents For Electrophotography (AREA)
  • Breeding Of Plants And Reproduction By Means Of Culturing (AREA)
  • Crushing And Grinding (AREA)
  • Debarking, Splitting, And Disintegration Of Timber (AREA)

Claims (6)

1. Verfahren zum Herstellen einer Papiermasse aus Holzplättchen, das darin besteht, daß die Holzplättchen in einer Zweischnecken-Maschine (1) vorbehandelt werden, in der sie einer Folge von Kompressions- und Expansionsvorgängen unter Einspritzen einer oder mehrerer Lösungen mindestens eines chemischen Mittels ausgesetzt werden, um dann die die Maschine verlassende Masse durch ein mechanisches Mittel zu zerfasern, dadurch gekennzeichnet, daß nach dem Zerfasern die Masse einem Siebrvorgang ausgesetzt wird, und daß die Rückstände des Siebvorganges in einer als Hammerzerfaserer ausgebildeten Vorrichtung (50) einem Zerfaserungsvorgang unterworfen werden.
2. Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß die Feuchtigkeit der dem Zerfaserungsvorgang unterworfenen Rückstände durch Einspritzen von nasser in den Hammerzerfaserer gesteuert wird, derart, daß am Ausgang des Zerfaserers der Trockengehalt der Maschine zwischen 2 und 20 % liegt.
3. Vorgang nach Anspruch 2, dadurch gekennzeichnet, daß die Rückstände des Siebvorganges nach Passieren des Hammerzerfaserers stromauf der Siebvorrichtung (40, 42) in den Zyklus zurückgeführt werden.
4. Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß die Zerfaserung der die Zweischnecken-Maschine (1) verlassenden Masse in feuchter Umgebung in einer als Hammerzerfaserer ausgebildeten Vorrichtung (20) erfolgt, wobei der Trockengehalt der Masse am Ausgang der Vorrichtung zwischen 2 und 20 % liegt.
5. Verfahren nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, daß die Öffnungen des Siebes des Hammerzerfaserers Löcher eines Durchmessers zwischen 1 mm und 5 mm sind.
6. Verfahren nach einem der Ansprüche 1 bis 3, dadurch gekennzeichnet, daß die Öffnungen des Siebes des Hammerzerfaserers Schlitze einer Breite zwischen 0,4 mm und 2 mm sind.
EP89400319A 1988-02-05 1989-02-03 Verfahren zum Zermahlen lignocelluloseartiger Materialien Expired - Lifetime EP0327469B1 (de)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT89400319T ATE74980T1 (de) 1988-02-05 1989-02-03 Verfahren zum zermahlen lignocelluloseartiger materialien.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8801333A FR2626905A1 (fr) 1988-02-05 1988-02-05 Procede de defibrage d'une matiere lignocellulosique
FR8801333 1988-02-05

Publications (2)

Publication Number Publication Date
EP0327469A1 EP0327469A1 (de) 1989-08-09
EP0327469B1 true EP0327469B1 (de) 1992-04-15

Family

ID=9362956

Family Applications (1)

Application Number Title Priority Date Filing Date
EP89400319A Expired - Lifetime EP0327469B1 (de) 1988-02-05 1989-02-03 Verfahren zum Zermahlen lignocelluloseartiger Materialien

Country Status (10)

Country Link
EP (1) EP0327469B1 (de)
JP (1) JPH02503096A (de)
AT (1) ATE74980T1 (de)
BR (1) BR8905289A (de)
DE (1) DE68901187D1 (de)
DK (1) DK488089D0 (de)
FI (1) FI894649A0 (de)
FR (1) FR2626905A1 (de)
IE (1) IE890243L (de)
WO (1) WO1989007169A1 (de)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2723598B1 (fr) * 1994-08-10 1996-10-18 Sorgho Agro Ind Et Papetier Sa Procede de demoellage de plantes a moelle, en particulier sorgho, en vue d'obtenir des fibres de qualite papetiere

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CH166508A (de) * 1932-10-13 1934-01-15 Asplund Arne J A Verfahren zur Zerfaserung von Lignin-Zellulose-Material.
US1949534A (en) * 1933-05-08 1934-03-06 Sturtevant Mill Co Method of and apparatus for hydrating cellulose pulp
FR1080539A (fr) * 1953-02-04 1954-12-09 Procédé de défibrage et de raffinage des matières cellulosiques par percussion et abrasion
FR1104813A (fr) * 1953-04-25 1955-11-24 Procédé de défibrage et lavage simultanés ou de raffinage de matières fibreuses et installation pour la réalisation du procédé
GB752534A (en) * 1953-10-13 1956-07-11 Aschaffenburger Zellstoffwerke Method of defibring incompletely defibred vegetable material
FR2418295A1 (fr) * 1978-02-27 1979-09-21 Creusot Loire Procede et installation de traitement en continu d'une matiere cellulosique

Also Published As

Publication number Publication date
DK488089A (da) 1989-10-04
DE68901187D1 (de) 1992-05-21
DK488089D0 (da) 1989-10-04
IE890243L (en) 1989-08-05
JPH02503096A (ja) 1990-09-27
ATE74980T1 (de) 1992-05-15
FR2626905A1 (fr) 1989-08-11
EP0327469A1 (de) 1989-08-09
FI894649A (fi) 1989-10-02
WO1989007169A1 (fr) 1989-08-10
BR8905289A (pt) 1990-08-21
FI894649A0 (fi) 1989-10-02

Similar Documents

Publication Publication Date Title
RU2373314C2 (ru) Установка для изготовления термомеханической древесной массы (варианты), способ термомеханического рафинирования древесной щепы (варианты) и комбинированная плита для диска рафинера
BE1006670A5 (fr) Procede perfectionne de traitement de feuilles de tabac.
US2008892A (en) Method of manufacture of pulp
EP1002154B1 (de) Verfahren zum konditionieren von faserigem lignozellulosematerial für zellstoffherstellung
NO127894B (de)
RU97104086A (ru) Способ высокотемпературного высокоскоростного измельчения древесной стружки с низкой продолжительностью обработки
JP2000017592A (ja) 微小繊維状セルロース及びその製造方法
US3016324A (en) Method and apparatus for producing wood pulp
EP0327469B1 (de) Verfahren zum Zermahlen lignocelluloseartiger Materialien
US2374046A (en) Method of disintegrating cellulosecontaining structures
CA1193405A (fr) Procede de fabrication d'une pate de fibres cellulosique pour utilisation non papetiere
EP0017544B1 (de) Verfahren zur Herstellung einer Papierpulpe
US6372086B1 (en) Pulper and countercurrent washer sugar cane extraction
FR2544757A1 (fr) Procede et appareil de digestion pour la production de pulpe de haute qualite
US3620910A (en) Process for the preparation of groundwood pulp from a dicotyledonous plant
US3688345A (en) Method for processing fibrous stalks
US2238666A (en) Defibration of textile plants
US2735762A (en) Washing
AU620378B2 (en) Process for removing the fibre from a lignocellulose material
US4237582A (en) Bagasse preparation
EP4257743A1 (de) Verfahren zur mechanischen behandlung von hanf zur herstellung einer formpaste
FR1465863A (fr) Procédé pour la fabrication de pâte à papier
CN115404710A (zh) 竹材制浆的工艺方法
CN112369648A (zh) 一种造纸法再造烟叶原料浸提方法
CN117344561A (zh) 一种制备高白度高强度针叶化机浆的方法

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

17P Request for examination filed

Effective date: 19890208

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE CH DE ES FR GB GR IT LI LU NL SE

17Q First examination report despatched

Effective date: 19910124

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): AT BE CH DE ES FR GB GR IT LI LU NL SE

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

Ref country code: IT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRE;WARNING: LAPSES OF ITALIAN PATENTS WITH EFFECTIVE DATE BEFORE 2007 MAY HAVE OCCURRED AT ANY TIME BEFORE 2007. THE CORRECT EFFECTIVE DATE MAY BE DIFFERENT FROM THE ONE RECORDED.SCRIBED TIME-LIMIT

Effective date: 19920415

Ref country code: ES

Free format text: THE PATENT HAS BEEN ANNULLED BY A DECISION OF A NATIONAL AUTHORITY

Effective date: 19920415

Ref country code: AT

Effective date: 19920415

Ref country code: GB

Effective date: 19920415

Ref country code: SE

Effective date: 19920415

Ref country code: NL

Effective date: 19920415

Ref country code: GR

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 19920415

REF Corresponds to:

Ref document number: 74980

Country of ref document: AT

Date of ref document: 19920515

Kind code of ref document: T

REF Corresponds to:

Ref document number: 68901187

Country of ref document: DE

Date of ref document: 19920521

NLV1 Nl: lapsed or annulled due to failure to fulfill the requirements of art. 29p and 29m of the patents act
GBV Gb: ep patent (uk) treated as always having been void in accordance with gb section 77(7)/1977 [no 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

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

Ref country code: LU

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 19930228

Ref country code: LI

Effective date: 19930228

Ref country code: CH

Effective date: 19930228

Ref country code: BE

Effective date: 19930228

26N No opposition filed
BERE Be: lapsed

Owner name: S.A. BEGHIN-SAY

Effective date: 19930228

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

Ref country code: FR

Effective date: 19931029

REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

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

Ref country code: DE

Effective date: 19931103

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST