US3791917A - Process for producing kraft paper laminate of top stock and base stock layers - Google Patents

Process for producing kraft paper laminate of top stock and base stock layers Download PDF

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Publication number
US3791917A
US3791917A US00338826A US3791917DA US3791917A US 3791917 A US3791917 A US 3791917A US 00338826 A US00338826 A US 00338826A US 3791917D A US3791917D A US 3791917DA US 3791917 A US3791917 A US 3791917A
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Prior art keywords
fiber
slurry
stock
screening
percent
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Expired - Lifetime
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US00338826A
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English (en)
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J Bolton
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Bird Machine Co Inc
Sulzer Papertec Mansfield Inc
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Bird Machine Co Inc
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Assigned to BIRD ESCHER WYSS reassignment BIRD ESCHER WYSS ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: BIRD MACHINE COMPANY, INC., A MA CORP.
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    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H27/00—Special paper not otherwise provided for, e.g. made by multi-step processes
    • D21H27/30—Multi-ply
    • 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
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21F—PAPER-MAKING MACHINES; METHODS OF PRODUCING PAPER THEREON
    • D21F1/00—Wet end of machines for making continuous webs of paper
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H11/00—Pulp or paper, comprising cellulose or lignocellulose fibres of natural origin only
    • D21H11/02—Chemical or chemomechanical or chemothermomechanical pulp
    • D21H11/04—Kraft or sulfate pulp

Definitions

  • Field of the Invention This invention relates to a process for producing a kraft paper laminate of top and base stock layers from high yield kraft slurry.
  • kraft paper laminate of the type concerned is used primarily in the production of box board, in which a corrugated paper liner is adhesively secured between two sheets of the kraft paper. So prevalent is this use that paper machines for forming the two superposed layers of the paper laminate have come to be known as liner-board machines.
  • top and base stock layers and the kraft fibers that go into them, have markedly different characteristics.
  • the top stock layer usually the only side exposed, is relatively thin and needs high quality fibers which are short and flexible for strength, smoothness, and brightness.
  • the thicker base layer can tolerate some fibers of lower quality such as long fiber shives.
  • the kraft fiber slurry used for each layer is produced from the wood in digesters, which may be of the continuous or batch types, wherein the wood chips are sub- .jected to chemical action in the presence of heat and pressure.
  • the yield of a digester is expressed as the percentage of oven dry (O.D.) wood in the slurry leaving the digester to the OD. wood fed to the digester. Yield varies inversely with the length and severity of the digestion treatment; whereas, the quality of the slurry varies directly therewith.
  • the quality of the slurry varies inversely with the percentage of rejects which it contains, this percentage being commonly accepted as the proportion that will not pass a cut flat screen (slots about 0.01 inch wide by l r inch long). Except at low yields, continuous digesters produce less rejects and hence better quality stock at a given yield than do batch digesters.
  • the mills have strong incentives to digest to big yields.
  • One of these is savings in wood cost, since an increase of yield of only a few per cent can save a mill as much as a million dollars or more annually in wood cost.
  • high yield digestion requires less chemicals and digester capacity, again saving substantial cost, with a corollary advantage that the lower amount of chemical can be more completely removed from mill waste water, with consequent benefit to the ecology.
  • Less waste fiber in high yield kraft saves money and again improves purification of mill waste water and stack gases, benefiting the ecology.
  • the quality of the slurry measured by its reject content decreases markedly and disproportionately with increased yield, particularly at or approaching high yields.
  • the rejects portion of the digested slurry is suitable with ordinary refining for use as the base stock layer of the kraft paper laminate, but is not suitable for the top stock layer.
  • the wood for the top stock is digested to low or medium yield and is suitable for use in the top layer using low horsepower prerefining for knot breaking, ordinary screening and washing, and low horsepower refining for freeness control.
  • the base layer stock is digested to high yield and, similarly treated but with additional refining in a regular higher horsepower base stock refiner, is used as the base stock.
  • the main disadvantage of this practice is its high capital cost, requiring two sets of digesters, blow tanks, prerefiners, screens and washers, as well as the regular refiner for the base stock.
  • the savings and other advantages from high yield digestion are only partially realized.
  • the mill is batch digesting all the wood for both layers in a single digestion system to a medium yield of about 52 percent.
  • the digested slurry is subjected to screening (0.070 inch diameter holes) to provide a 50 percent accept fraction which is washed and about 40 percent of it used directly to form the top stock layer.
  • the 50 percent reject fraction is subjected to refining in ordinary base stock refiners, washed and, with the about percent remainder of the accept fraction added to it, is used to form the base stock layer.
  • This process is less costly to install and operate than the process involving ultrarefiners since it uses less costly, ordinary refiners on only half the stock.
  • the process has the drawbacks of only partially realizing the advantages of high yield versus low yield digestion, and the product is a compromise in that the screening accepts portion contains some fibers undesirable for the top stock layer.
  • An object of this invention is to provide a process of making a kraft paper laminate of top and base stock layers from a single slurry which has been digested to a high yield, which process does not involve the high capital and operation cost of the process utilizing ultrarefiners and yet obtains fully the advantages of high yield digestion.
  • Another object is to provide such a process wherein the fiber of the top stock layer is essentially only fiber having the desired characteristics, and provides a top stock layer of a quality at least as good as that produced by the separate digestion systems process and better than is obtained in the other two processes mentioned above.
  • the preferred process just described has been found to produce an accept fraction, having less than 1 percent of the reject content of the slurry and provides a better quality top stock layer of the laminate than the process using an ultrarefiner as described above, having better brightness and strength with less of the undesirable shives.
  • the top stock layer so produced is similarly better than that obtained with the 50-50 screening process and at least as good as the product of the process separately digesting the stock for each layer, while the base stock layer is as good as is required.
  • the superior quality of the top stock layer is due in part to the fact that the screen accepts fraction of the high yield kraft is of better quality than stock produced from medium or low yield kraft.
  • the equipment cost and its operating cost in the process of this invention are substantially less than in the process utilizing ultrarefining, which is the only prior process known to applicant in which all the stock for both layers is digested to high yield, with all the advantages this entails.
  • the screening machine used in the preferred process as described is capable not only of effecting the desired clean separation of the good top stock fiber but also of separating most of it even where its amount is low such as 30 percent or less, a surprising result when it is considered that it is mixed with such a large amount of reject material.
  • the high frequency and intensity of the pulsation produced by the rotor keeps the slurry content in a constant state of agitation such that virtually all of the fiber in the slurry has access to the open area of the screen.
  • the about 20-80 percent separation at the screen is preferred for several reasons. One is that these are about the right proportions to provide top and base layers of requisite thickness. A more important reason is that the machine operates very effectively in separating in these proportions. Separation at a higher ratio of accepts to rejects is likely to produce accepts with more undesirable fiber content and provides more fiber than is needed for the top stock, with about 30 percent the upper limit for providing accepts of requisite quality. Separation at a lower ratio is possible but if less than about 10 percent probably will not provide sufficient fiber for the top stock layer and will necessitate another screening of the rejected portion to make up the deficiency.
  • FIG. 2 is a flow sheet illustrating a practice of the process of the invention.
  • FIG. 1 the two curves show the percent of rejects in continuous and batch digested kraft respectively on the vertical scale at the left for yields from low to high on the horizontal scale at the bottom. It will be noted that for yields of percent or lower both curves show reject percentages below 20 percent. Above 50 percent yield the batch digestion curve climbs steeply, increasing from less than 40 percent rejects at a yield of 53 percent to more than 60 percent rejects at a yield of 56 percent. At a yield of percent the continuous digestion curve shows a reject content of only 30 percent but an increase of continuous digestion yield from 55 to 60 percent increases the reject content to about percent.
  • This accepted fraction goes to washer 20 from which it is fed to be ultimately formed into the top stock layer on the linerboard machine.
  • the slurry portion rejected by the screen of machine 18 goes to regular base stock refiner 22, thence to coarse screen 24 (e.g. 0.078 to 0.094 holes) from which the reject fraction is returned to the inlet of refiner 22, while the accepted fraction goes from screen 24 via washer 26 to be ultimately formed into the base stock layer of the paper laminate.
  • Refiner 22 may be capable of operation as an ultrarefiner but if so, will usually be operated at lower horsepower than is required for ultrarefining.
  • the flow sheet of FIG. 3 differs from that of FIG. 2 in that screening machine 18 operates on brown stock, there being interposed between prerefiner 14 and machine 18 pulp refiner 30 and washer 32, the latter making unnecessary washers 20 and 26 of FIG. 2.
  • screening machine 18 In the process as illustrated in the flow sheet of either FIGS. 2 or 3, if screening machine 18 is operated to accept more fiberthan is needed for the top stock layer, the excess thereof may be added to the rejected portion of slurry, preferably after it has been refined. In either flow sheet, if the screening machine 18 does not accept a sufficient quantity of fibers to form the top stock layer, the deficiency may be made up, for example, by providing a second screening machine 18 of like construction and operation to the first one and feeding thereto some or all of the stock accepted by screen 24, to provide an accept fraction containing acceptable fiber lost in the portion rejected by the first machine 18, and additional such fiber produced in the refining.
  • the fraction accepted by the screen of this second machine may then be added to the fraction accepted by the screen of the first machine to form the top stock layer, while the slurry portion rejected by the screen of the second machine is used to form the base layer.
  • a process for producing a kraft paper laminate of top stock and base stock layers from kraft fiber slurry which has been digested to a yield of at least 54 percent which comprises the steps of:

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  • Engineering & Computer Science (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Wood Science & Technology (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Paper (AREA)
US00338826A 1973-03-07 1973-03-07 Process for producing kraft paper laminate of top stock and base stock layers Expired - Lifetime US3791917A (en)

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US33882673A 1973-03-07 1973-03-07

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US (1) US3791917A (enrdf_load_stackoverflow)
JP (1) JPS49124309A (enrdf_load_stackoverflow)
BR (1) BR7401702D0 (enrdf_load_stackoverflow)
CA (1) CA993700A (enrdf_load_stackoverflow)
FR (1) FR2220622B1 (enrdf_load_stackoverflow)
GB (1) GB1402516A (enrdf_load_stackoverflow)

Cited By (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2439380A1 (fr) * 1978-10-20 1980-05-16 Ogasawara Hiromi Detecteur de deplacement a mouvement rectiligne
US4332638A (en) * 1979-03-06 1982-06-01 J. M. Voith Gmbh Method and apparatus for the recovery of a suspension of fibrous material from mixed waste paper
FR2542774A1 (fr) * 1983-03-14 1984-09-21 Mo Och Domsjoe Ab Procede de fabrication de pate mecanique amelioree
US4504016A (en) * 1982-07-02 1985-03-12 Wikdahl Nils Anders Lennart Process for cleaning chemical cellulose pulp by screening and apparatus
US4781793A (en) * 1986-07-04 1988-11-01 Valmet Oy Method for improving paper properties in multiply paper using long and short fiber layers
WO1991010774A1 (en) * 1990-01-15 1991-07-25 Mo Och Domsjö Aktiebolag Environmental pulp, method for its manufacture and use of pulp
US5051168A (en) * 1988-08-04 1991-09-24 Oy Tampella Ab Device for screening and treating pulp
US5145010A (en) * 1988-01-22 1992-09-08 Sunds Defibrator Industries Aktiebolag Method of making mechanical pulp
WO1992021816A1 (en) * 1991-05-28 1992-12-10 The Procter & Gamble Company Cellulose pulps of selected morphology for improved paper strength potential
US5405499A (en) * 1993-06-24 1995-04-11 The Procter & Gamble Company Cellulose pulps having improved softness potential
US5503710A (en) * 1995-05-31 1996-04-02 Macmillan Bloedel Limited Duplex linerboard formed from old corrugated containers
US5643413A (en) * 1994-10-11 1997-07-01 Hoffman Environmental Systems, Inc. Multi-ply paper product and method of making the same
US5679218A (en) * 1994-07-29 1997-10-21 The Procter & Gamble Company Tissue paper containing chemically softened coarse cellulose fibers
US5770013A (en) * 1996-06-21 1998-06-23 Potlatch Corporation Method for manufacturing paper and paper fabricated from the same method
US20030111198A1 (en) * 2001-12-19 2003-06-19 Kimberly-Clark Worldwide, Inc. Tissue products and methods for manufacturing tissue products
US20030111197A1 (en) * 2001-12-19 2003-06-19 Kimberly-Clark Worldwide, Inc. Method and system for manufacturing tissue products, and products produced thereby
RU2208079C2 (ru) * 1997-07-09 2003-07-10 Биллеруд Шерблака Аб Крафт-бумага и способ ее изготовления
US20030127203A1 (en) * 2001-12-19 2003-07-10 Kimberly-Clark Worldwide, Inc. Use of fractionated fiber furnishes in the manufacture of tissue products, and products produced thereby
US20050039868A1 (en) * 2003-08-18 2005-02-24 Kimberly-Clark Worldwide, Inc. Recycling of latex-containing broke
CN114423899A (zh) * 2019-09-20 2022-04-29 福伊特专利有限公司 净化方法

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CH649112A5 (de) * 1980-10-03 1985-04-30 Escher Wyss Gmbh Verfahren zum fraktionieren von aus altpapier gewonnenem faserstoff sowie anlage zur ausfuehrung des verfahrens.
SE441282B (sv) * 1984-02-22 1985-09-23 Mo Och Domsjoe Ab Forfarande for framstellning av forbettrad hogutbytesmassa

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1880692A (en) * 1931-06-27 1932-10-04 Beloit Iron Works Method of and apparatus for making paper
US2098733A (en) * 1937-09-20 1937-11-09 Hummel Ross Fibre Corp Plyboard
US2370393A (en) * 1942-02-11 1945-02-27 William G Brubacher Method and apparatus for making wallboard
US3301745A (en) * 1963-04-26 1967-01-31 Scott Paper Co Pulp processing method for mixed cellulosic materials
US3363759A (en) * 1964-04-29 1968-01-16 Bird Machine Co Screening apparatus with rotary pulsing member

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1880692A (en) * 1931-06-27 1932-10-04 Beloit Iron Works Method of and apparatus for making paper
US2098733A (en) * 1937-09-20 1937-11-09 Hummel Ross Fibre Corp Plyboard
US2370393A (en) * 1942-02-11 1945-02-27 William G Brubacher Method and apparatus for making wallboard
US3301745A (en) * 1963-04-26 1967-01-31 Scott Paper Co Pulp processing method for mixed cellulosic materials
US3363759A (en) * 1964-04-29 1968-01-16 Bird Machine Co Screening apparatus with rotary pulsing member

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
Pulp and Paper Manufacture, Volume III; 2nd Edition McGraw Hill Book Company, New York 1970 pp. 131 147. *

Cited By (28)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2439380A1 (fr) * 1978-10-20 1980-05-16 Ogasawara Hiromi Detecteur de deplacement a mouvement rectiligne
US4332638A (en) * 1979-03-06 1982-06-01 J. M. Voith Gmbh Method and apparatus for the recovery of a suspension of fibrous material from mixed waste paper
US4504016A (en) * 1982-07-02 1985-03-12 Wikdahl Nils Anders Lennart Process for cleaning chemical cellulose pulp by screening and apparatus
FR2542774A1 (fr) * 1983-03-14 1984-09-21 Mo Och Domsjoe Ab Procede de fabrication de pate mecanique amelioree
US4781793A (en) * 1986-07-04 1988-11-01 Valmet Oy Method for improving paper properties in multiply paper using long and short fiber layers
US5145010A (en) * 1988-01-22 1992-09-08 Sunds Defibrator Industries Aktiebolag Method of making mechanical pulp
US5051168A (en) * 1988-08-04 1991-09-24 Oy Tampella Ab Device for screening and treating pulp
US5145072A (en) * 1988-08-04 1992-09-08 Oy Tampella Ab Method for screening and treating pulp
WO1991010774A1 (en) * 1990-01-15 1991-07-25 Mo Och Domsjö Aktiebolag Environmental pulp, method for its manufacture and use of pulp
WO1992021816A1 (en) * 1991-05-28 1992-12-10 The Procter & Gamble Company Cellulose pulps of selected morphology for improved paper strength potential
US5228954A (en) * 1991-05-28 1993-07-20 The Procter & Gamble Cellulose Company Cellulose pulps of selected morphology for improved paper strength potential
US5405499A (en) * 1993-06-24 1995-04-11 The Procter & Gamble Company Cellulose pulps having improved softness potential
US5582685A (en) * 1993-06-24 1996-12-10 The Procter & Gamble Company Method for producing a cellulose pulp of selected fiber length and coarseness by a two-stage fractionation
US5679218A (en) * 1994-07-29 1997-10-21 The Procter & Gamble Company Tissue paper containing chemically softened coarse cellulose fibers
US5643413A (en) * 1994-10-11 1997-07-01 Hoffman Environmental Systems, Inc. Multi-ply paper product and method of making the same
US5503710A (en) * 1995-05-31 1996-04-02 Macmillan Bloedel Limited Duplex linerboard formed from old corrugated containers
US5770013A (en) * 1996-06-21 1998-06-23 Potlatch Corporation Method for manufacturing paper and paper fabricated from the same method
RU2208079C2 (ru) * 1997-07-09 2003-07-10 Биллеруд Шерблака Аб Крафт-бумага и способ ее изготовления
US6797114B2 (en) 2001-12-19 2004-09-28 Kimberly-Clark Worldwide, Inc. Tissue products
US20030111197A1 (en) * 2001-12-19 2003-06-19 Kimberly-Clark Worldwide, Inc. Method and system for manufacturing tissue products, and products produced thereby
US20030127203A1 (en) * 2001-12-19 2003-07-10 Kimberly-Clark Worldwide, Inc. Use of fractionated fiber furnishes in the manufacture of tissue products, and products produced thereby
US20030111198A1 (en) * 2001-12-19 2003-06-19 Kimberly-Clark Worldwide, Inc. Tissue products and methods for manufacturing tissue products
US6821387B2 (en) 2001-12-19 2004-11-23 Paper Technology Foundation, Inc. Use of fractionated fiber furnishes in the manufacture of tissue products, and products produced thereby
US20050034826A1 (en) * 2001-12-19 2005-02-17 Sheng-Hsin Hu Tissue products and methods for manufacturing tissue products
US6946058B2 (en) 2001-12-19 2005-09-20 Kimberly-Clark Worldwide, Inc. Method and system for manufacturing tissue products, and products produced thereby
US20050039868A1 (en) * 2003-08-18 2005-02-24 Kimberly-Clark Worldwide, Inc. Recycling of latex-containing broke
US7364642B2 (en) 2003-08-18 2008-04-29 Kimberly-Clark Worldwide, Inc. Recycling of latex-containing broke
CN114423899A (zh) * 2019-09-20 2022-04-29 福伊特专利有限公司 净化方法

Also Published As

Publication number Publication date
FR2220622B1 (enrdf_load_stackoverflow) 1977-06-10
GB1402516A (en) 1975-08-13
FR2220622A1 (enrdf_load_stackoverflow) 1974-10-04
CA993700A (en) 1976-07-27
JPS49124309A (enrdf_load_stackoverflow) 1974-11-28
BR7401702D0 (pt) 1974-11-05

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Owner name: BIRD ESCHER WYSS, MASSACHUSETTS

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:BIRD MACHINE COMPANY, INC., A MA CORP.;REEL/FRAME:005315/0311

Effective date: 19890509