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WO1996007786A1 - Procede de cuisson continue de pate kraft avec pretraitement de la liqueur noire - Google Patents

Procede de cuisson continue de pate kraft avec pretraitement de la liqueur noire Download PDF

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Publication number
WO1996007786A1
WO1996007786A1 PCT/US1995/007074 US9507074W WO9607786A1 WO 1996007786 A1 WO1996007786 A1 WO 1996007786A1 US 9507074 W US9507074 W US 9507074W WO 9607786 A1 WO9607786 A1 WO 9607786A1
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WO
WIPO (PCT)
Prior art keywords
uquor
spent
vessel
digester
concentration
Prior art date
Application number
PCT/US1995/007074
Other languages
English (en)
Inventor
Kaj O. Henricson
Pekka Tervola
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 AU26972/95A priority Critical patent/AU2697295A/en
Publication of WO1996007786A1 publication Critical patent/WO1996007786A1/fr

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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
    • D21C3/00—Pulping cellulose-containing materials
    • D21C3/02—Pulping cellulose-containing materials with inorganic bases or alkaline reacting compounds, e.g. sulfate processes
    • D21C3/022—Pulping cellulose-containing materials with inorganic bases or alkaline reacting compounds, e.g. sulfate processes in presence of S-containing compounds
    • 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
    • D21C3/00—Pulping cellulose-containing materials
    • D21C3/22—Other features of pulping processes
    • D21C3/24—Continuous processes
    • 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
    • D21C7/00—Digesters

Definitions

  • kraft cooking wood is delignified by a cooking liquor where the active components are Na 2 S and NaOH.
  • Na 2 S is preferably primarily active at the beginning of the cook, and NaOH is preferably active at the end of the cook.
  • the invention relates to a method of increasing Na 2 S concentration in the beginning of the cook. A high Na 2 S concentration in the beginning of the cook gives a more selective cook and the possibility of lowering pulp kappa.
  • Spent kraft cooking liquor, or black liquor has been re- circulated for re-use in various fashions in prior art continuous kraft cooking systems.
  • black liquor is added to the feed system of a continuous digester to aid in flushing chips from the high pressure transfer device (i.e., the high pressure feeder) to the top of the impregnation vessel.
  • high pressure transfer device i.e., the high pressure feeder
  • black liquor is used to supplement the liquor extracted in the impregnation vessel.
  • These patents disclose a method of introducing co- and counter-current chip impregnation in an impregnation vessel by extracting liquor at a midpoint in the vessel.
  • the re-circulated black liquor is used to increase the liquor volume (i.e., the liquor-to-wood ratio) to limit the alkali concentration increase caused by the extraction.
  • the black liquor also improves the chip column movement.
  • U.S.patents 5,053,108 and 5,236,553 disclose a method of continuous kraft cooking in which black liquor is re-circulated to the feed system to treat the wood chips. In the '108 patent this treatment takes place in the chip chute and is referred to as "sulfonation". In the '553 patent, the black liquor is re-circulated to a chip chute/slurrying vessel.
  • a method of continuously kraft cooking comminuted cellulosic fibrous material utilizing an upright continuous digester having first and second extraction screens, a top, and a bottom is provided. The method comprises the steps of continuously: (a) Feeding comminuted cellulosic fibrous material slurry to the top of the digester, (b)
  • step (c) is typically practiced to extract as the first spent liquor a Uquor having an effective alkali concentration of about 10-50 g/1 and an Na 2 S concentration (assuming original sulfidity of the cooking Uquor of greater than about 25%) of greater than about 35 g/1.
  • the first Uquor is also typically at a temperature of about 140-170° C and in an amount of about 2-6 m 3 p.
  • Step (d) of the above method is typicaUy practiced to extract as the second spent Uquor a Uquor having an effective alkaU concentration of about 5-20 g/1 (typicaUy half or less of the concentration of the first Uquor), and an Na 2 S concentration of less than about 20 g 1 (typicaUy less than half of that of the first Uquor).
  • the second Uquor typically has a temperature of about 120- 160° C and is extracted in an amount of about 2-6 m 3 /tp.
  • the digester may comprise a two vessel hydrauUc system including a first impregnation vessel, in which case step (e) may be practiced to introduce the first spent Uquor into the bottom of the impregnation vessel to flow countercurrently to the material therein, or the digester may comprise a single vessel hydrauUc digester in which case the first Uquor may be introduced into the slurry any time prior to the practice of step (a).
  • the second spent Uquor may be flashed to steam in a flash tank, and a more concentrated second spent Uquor which is withdrawn from the bottom of the flash tank may be used to slurry the comminuted ceUulosic fibrous material prior to step (a).
  • the more concentrated second spent Uquor may be introduced into contact with the material in the feed circulation loop of the high pressure transfer device, i.e. slurrying the material.
  • the first Uquor may also be flashed if desired, before adding it to the cellulosic material upstream of the digester cooking zone.
  • a method of continuously digesting comminuted ceUulosic fibrous material to produce cellulose pulp comprises the steps of substantially consecutively and continuously: (a) Slurrying the material with Uquor. (b) Treating the material with a first sulphurous Uquor having an effective alkali concentration of about 10-50 g/1 and an Na 2 S concentration of at least about 35 g/1 (e. g. 40-60 g/1). (c) Cooking the material with cooking Uquor having an effective -.llral.
  • step (a) may be practiced, at least in part, using the second Uquor from step (e).
  • the first and second Uquors preferably have the temperature ranges and volumes described above with respect to a first aspect of the present invention.
  • the second Uquor typicaUy has an effective alkali concentration of about 5-20 g/1 (e.g. about 10 g/1) and less than the effective alkali concentration of the first Uquor, and has an Na 2 S concentration of less than about 20 g/1 (e.g. about 10-15 g 1).
  • a continuous digester system comprises the foUowing elements: An upright digester vessel having a top and a bottom.
  • a chip feed system connected to the chip feed inlet.
  • a separating device adjacent the top of the vessel for separating some Uquor from chips fed into the chip feed inlet and returning it to the chip feed system.
  • At least one upper screen in the vessel distinct from the separating device.
  • a first conduit for circulating the first spent Uquor to the chip feed system.
  • a chip slurrying system is also preferably provided connected to the chip feed system opposite the digester.
  • a second conduit is also provided for circulating Uquor from the second extraction screen to the slurrying system.
  • the second conduit may be connected directly to the slunying system, or through one or more flash tanks.
  • the invention also may include a simplified steaming and slurrying system associated with the digester. For example instead of utilizing a chips bin, chip meter, chip feeder, horizontal steaming vessel, slurrying vessel, and high pressure feeder, the steaming and slurrying system may consist essentiaUy of only a chip bin, chip feeder, slurrying vessel (e.g. chute), and high pressure feeder.
  • the continuous digester system may comprise any of a wide variety of conventional digester systems including digesters available from Kamyr, Inc. of Glens FaUs, New York and sold under the trademarks MCC®, EMCC®, and LO-SOLIDSTM; the continuous digester system may include a single vessel hydrauUc system, a two vessel hydrauUc system (with an impregnation vessel in addition to the digester), or other conventional systems.
  • the first conduit may be connected to the impregnation vessel to introduce the first spent Uquor into the impregnation vessel.
  • the first, sulphurous, Uquor typically flows countercurrently to the ceUulosic material, but may instead be directed to flow co-currently.
  • FIGURE 1 is a schematic view of exemplary apparatus for practicing the method of continuous kraft cooking with black Uquor pretreatment according to the present invention
  • FIGURE 2 is a view like that of FIGURE 1 utiUzing a conventional Kamyr® two vessel hydrauUc digester system with co- current Uquor flow in the top of the digester
  • FIGURE 3 is a view like that of FIGURE 2 only not showing the chip bin and other conventional components, and showing a countercurrent Uquor flow in the top of the digester;
  • FIGURE 4 is a view like that of FIGURE 2 for a single vessel hydrauUc EMCC® digester system
  • FIGURE 5 is a schematic view of a conventional prior art chip feeding system for a continuous digester
  • FIGURE 6 is a schematic side view of a modified chip feeding system for a continuous digester that may be utiUzed in the practice of the present invention.
  • FIGURE 1 Exemplary apparatus for practicing an exemplary method according to the present invention is shown schematicaUy in FIGURE 1.
  • the comminuted ceUulosic fibrous material that is digested to produce ceUulose pulp wiU be referred to as "chips", since wood chips are typicaUy used in the production of ceUulose pulp.
  • chips comminuted ceUulosic fibrous material that is digested to produce ceUulose pulp wiU
  • Presteamed chips in line 10 are fed to a first, impregnation, vessel 11.
  • the chips 10 are presteamed and pressurized in a slurrying and steaming system shown in FIGURES 2 or 3.
  • Cooking Uquor typicaUy white Uquor (WL), primarily comprising Na 2 S and NaOH as the active ingredients, is added to the lower portion 14 of vessel 11 and upper portion 15 of vessel 13. Additional cooking Uquor may be added to even out the alkaU profile according to cooking methods such as those using MCC®, EMCC® or LO- SOLIDSTM digesters. As an example, WL is added in FIGURE 1 to the bottom 16 of vessel 13.
  • WL is added in FIGURE 1 to the bottom 16 of vessel 13.
  • the chips are steamed to remove air and to aUow ready penetration by impregnating and cooking Uquors, as is conventional.
  • the actual cooking takes place in upper parts of digester 13.
  • the NaOH concentration decreases.
  • the cooking vessel 13 is equipped with two separate extraction screens 17 and 18. With the first extraction screen 17 is extracted Uquor surrounding the chips which Uquor stiU contains active cooking chemicals NaOH and Na 2 S.
  • This first, spent, extracted Uquor in conduit 19 is, due to the cooking kinetics, rich in Na 2 S and very useful in the beginning of the cook (e.g. at the top of vessel 13), but not as useful where it is present at the end of the cook where primarily NaOH is needed.
  • the cook continues for a while after which a second, spent residual Uquor, caUed black Uquor, is separated by second screen 18 into second conduit 20.
  • the black Uquor in conduit 20 contains residual cooking chemicals and dissolved lignin and wash Uquid introduced into conduit 21 used to wash the pulp.
  • Typical properties of the black Uquor in conduit 20 are: temperature 150° C (120-160° C) effective alkaU 10 g 1 (5-20 g/1) amount 4 m 3 /tw (2-6 m 3 tw)
  • the second spent Uquor (black Uquor) in conduit 20 is so depleted in cooking chemicals that it has no significant potential as a cooking Uquor.
  • it can be utiUzed in a number of different ways before it is ultimately passed to a conventional recovery system. For example, as iUustrated in FIGURE 1, it may pass to a flash tank 22 to produce steam 23 that is used in presteaming the chips 10, with a more concentrated second (black) Uquor removed from the flash tank in line 24.
  • first and second extraction screens 17, 18 respectively are toward the end of the cooking zone in the digester 13.
  • these screens are located near the middle of the digester 13, but below at least one upper screen 25, the upper screen 25 iUustrated in FIGURE 1 associated with the conventional recirculation loop 26, to which white Uquor may be added if desired.
  • Typical white Uquor that is used wiU have, during cooking, an active alkali content of at least about 100 g 1, and a sulfidity of at least about 25%. The sulfidity may vary depending upon where the white Uquor is introduced.
  • the Uquor introduced initiaUy may have higher sulfidity (e.g. above 40%), while white Uquor introduced later on (e.g. at 16) lower 10
  • the temperature during cooking is around 160° C, preferably about 150-170° C.
  • the first spent Uquor from conduit 19 is mixed with the presteamed chips in line 10 prior to introduction into the top 15 of the digester 13.
  • the first Uquor may also be flashed to recover steam, if desired, before being mixed with the presteamed chips in line 10.
  • This is preferably accomplished - as iUustrated in FIGURE 1 — by introducing it into the recirculatory loop 28 at the bottom of impregnation vessel 11.
  • the first, sulphurous, Uquor flows upwardly in the impregnation vessel 11 countercurrent to the flow of chips (downward) adjacent the bottom of the vessel 11.
  • the temperature at the circulation 28 is typicaUy about 150° C (130- 160° C).
  • the sulphurous Uquor reacts with the wood and sulphur diffuses into the chips. Typical reaction and diffusion times are about 30 minutes (e.g. 20-40 minutes).
  • the second spent Uquor (black Uquor) from conduit 24 is introduced into the vessel 11 adjacent the circulation 30, slurrying the presteamed chips in conduit 10.
  • the temperature is about 90-120° C.
  • the black Uquor flows downwardly with the chips in the vessel 11 until the intermediate extraction screen 31 is reached.
  • the extraction screen 31 extracts "final" black Uquor.
  • two different streams may be provided, a first stream 32 which is recirculated back to the line 24 for introduction at 30 to slurry the chips, and a second portion 33 which is fed to the flash tank 34.
  • Steam 35 produced in flash tank 34 is fed to presteam the chips in line 10, and a first portion of the more concentrated black Uquor which is extracted from the bottom of the flash tank 34 may flow in line 36 back to the line 32 to slurry the chips.
  • the majority of the concentrated black Uquor from flash tank 34 passes in line 37 to evaporators in a conventional chemical recovery loop for a kraft miU.
  • FIGURE 2 schematicaUy iUustrates a second form of the invention in which the teachings of the invention are employed with a conventional two vessel hydrauUc KAMYR® continuous digester system. In this embodiment structures comparable to those in the FIGURE 1 embodiment are shown by the same reference numeral.
  • the conventional upper and lower extraction screens correspond to the first and second extraction screens 17, 18 according to the present invention.
  • the first spent (sulphurous) Uquor withdrawn in conduit 19 is used to — as in the FIGURE 1 embodiment - treat the chips prior to cooking, and therefore is introduced into the bottom of the impregnation vessel 11 as indicated generaUy at 40 in FIGURE 2 - or in the recirculation line 41 between the top 15 of the digester 13 and the bottom of the impregnation vessel 11, typicaUy right before the heaters 42, or — alternatively or in addition - after the heaters 42, as iUustrated at 43 in FIGURE 2.
  • a conventional separating device shown schematicaUy at 44 in FIGURE 2 — such as a screen assembly, or alternatively a "stilling weU", or a conventional top separator, is used to separate some of the slurrying Uquid from the introduced chips to be fed to the line 41.
  • a screen assembly or alternatively a "stilling weU", or a conventional top separator
  • the second spent Uquor black Uquor
  • some of the black Uquor in line 20 passes to the flash tanks 22, 22' and this concentrated black Uquor is then passed to evaporators and to other conventional chemical recovery system components.
  • the black Uquor - in line 45 - is used to slurry the chips, for example being introduced into the recirculation loop 46 associated with a high pressure transfer device (feeder) 47, as indicated at 48 in FIGURE 2.
  • the high pressure transfer device 47 and loop 46 associated therewith are conventional in two vessel hydrauUc systems for feeding presteamed chips in line 10 to the top of the impregnation vessel 11, and the black Uquor introduced at 48 is introduced in the recirculatory line 49 from the top of the impregnation vessel 11 to the high pressure pump 50 associated with the high pressure feeder 47.
  • FIGURE 2 also iUustrates a conventional steaming system for producing the steamed chips, which are slurried before passing into conduit 10 and before being introduced to the top of impregnation vessel 11.
  • FIGURE 2 iUustrates a pressurized chip bin 51 with a chip meter 52, low pressure feeder 53, horizontal steaming vessel 54, and vessel — chute - 55 in which a Uquid level is established for Uquid that wiU slurry the steamed chips discharged from horizontal steaming vessel 54.
  • a valve 56 may be provided, if desired, between the first and second conduits 19, 20, to make minor adjustments in the amount of spent Uquor flowing in each of the conduits 19, 20 if more Uquor is needed in one conduit than the other.
  • the valve 56 is controUed automaticaUy as is conventional.
  • FIGURE 3 iUustrates a system si ⁇ nlar to that in FIGURE 2 and the same components are iUustrated by the same reference numerals. In this embodiment, however, there is a countercurrent Uquid flow in the top of the digester 13, as indicated by the arrow 57.
  • a bottom circulation screen iUustrated schematicaUy at 58 acts as a top separator in FIGURE 3.
  • the "first screen" for withdrawing the first spent Uquor is either the trim screen, iUustrated schematicaUy at 59, or the bottom circulation screen (e. g. 58), or a combination of both, both screens 58, 59 being conventional in a two vessel hydrauUc system, and associated with the recirculation line 41, and having the conventional pumps 60, 61, respectively, associated with screens 58, 59. Therefore in this embodiment the sulphurous Uquor is returned to the bottom of the impregnation vessel 11, to flow upwardly therein, by the conventional recirculation line 41.
  • FIGURE 4 iUustrates the appUcation of the teachings of the invention to a conventional single vessel hydrauUc digester system.
  • the FIGURE 4 system is very similar to that of FIGURE 2, and comparable components to the FIGURE 2 embodiment are shown by the same reference numeral, except that there is no impregnation vessel.
  • a conventional cooking circulation loop 65 including an upper screen set 66, is associated with the digester 13 above the first and second extraction screens 17, 18, but below top separator 44.
  • the bulk of the impregnation of the chips with cooking Uquor takes place in the transfer line 12 and adjacent the top 15 of the digester 13, while no ⁇ naUy cooking takes place from about the level of screen 66 down to the extraction screens 17, 18.
  • the first spent Uquor (sulphurous Uquor) in conduit 19 may be introduced into the chips in the transfer line 12, as indicated at reference numeral 70 in FIGURE 4, while the second spent Uquor (black Uquor) in line 45 may be introduced into the conduit 71 associated with the slurrying vessel/chute 55 which suppUes slurried steamed chips to the high pressure feeder 47.
  • the strong (first) spent Uquor may pass counter-currently in situ as in the counter-current mode at the top of the digester 13 in FIGURE 3.
  • an extraction must be taken from one of the upper digester screens in FIGURE 4 so that a counter-current flow of Uquor results below the screen, yielding a higher sulfidity Uquor during the early stages of cooking.
  • the extraction from the upper screen would then typicaUy be taken to one or more flash tanks, and to conventional chemical recovery.
  • the sulphur content of the sulphurous Uquid in conduit 19 may be enhanced by using green Uquor as a source of sulfide.
  • Green Uquor is an aqueous solution of primarily sodium carbonate and sodium sulfide. In conventional practice the carbonate is causticized to NaOH to produce white Uquor.
  • the sulfide in green Uquor can perform the same function as sulfide of the first spent Uquor in line 19 .
  • Green Uquor may be added to either of the first or second spent Uquors in lines 19, 20 to enhance sulfidity, although typicaUy any green Uquor added would be added to the first spent Uquor in line 19, as iUustrated at 73 in FIGURE 4 (green Uquor may also be used in the FIGURES 1-3 embodiments too, typicaUy added to line 19 although it could be added elsewhere).
  • the added green Uquor volume may be from just above 0 to about 2 Vton of pulp. WhUe the embodiments iUustrated in FIGURES 2 through 4 illustrate a number of different embodiments it is to be understood 15
  • the relative sulfide concentrations of the two different Uquors is at least 25%, and typicaUy more on the order of about 4:1.
  • the white Uquor has 140 g/1 active al ali and 35% sulfidity, is provided in Table I below.
  • FIGURE 5 schematicaUy shows a conventional prior art system, similar to that iUustrated in FIGURE 2, in which a pressurized chip bin 51, chip meter 52, low pressure feeder 53, horizontal steaming vessel 54, and slurrying vessel/chute 55 are associated with the high pressure feeder 47 to steam and slurry the chips.
  • the use of the steaming vessel 54 typicaUy results in the temperature at the top of the impregnation vessel 11 being above 100°C, usuaUy about 120°C, and the low pressure feeder 53 is necessary to isolate the significantly different pressures of the chip bin 51 and chip meter 52 from the steaming vessel 54.
  • a lower temperature can be held at the top of the impregnation vessel 11.
  • the feed/slurrying system iUustrated in FIGURE 6 can be utiUzed, in which just the chip bin 51', chip meter 52, and slurrying vessel/chute 55 may be utilized.
  • the chips are presteamed to only about 100° C in the unpressurized chip bin 51' [sHghtly different than the pressurized chip bin 51, and simpler].

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Abstract

L'invention concerne un procédé et un système continu de digestion assurant une concentration élevée en Na2S au commencement de la cuisson de fibres de cellulose fines pour produire de la pâte cellulosique, assurant une cuisson plus sélective et permettant une cuisson jusqu'à un indice kappa plus bas. Deux liqueurs différentes (liqueur sulfureuse et liqueur noire) sont soutirées de différents tamis associées avec les digesteurs continus. La liqueur usée provenant du tamis qui se trouve le plus haut a une concentration effective assez élevée en alcali et en Na2S. La seconde liqueur usée provenant du second tamis a des concentrations effectives en alcali et en Na2S qui sont inférieures par au moins 25 % à celles trouvées dans la première liqueur usée. On fait circuler la première liqueur usée dans un récipient d'imprégnation ou une autre partie du système d'alimentation en copeaux, pour augmenter la quantité de soufre présente au commencement de l'étape de cuisson dans le digesteur. La seconde liqueur usée peut être utilisée de différentes manières, par exemple, sans ou après un passage par un collecteur de purge, à l'entrée d'un système de formation d'une pâte avec les copeaux avant leur introduction dans le digesteur. Le système de traitement par la vapeur et de formation d'une pâte peut comprendre uniquement un silo à copeaux non pressurisé, un dispositif d'alimentation en copeaux, une cuve de formation d'une pâte et un dispositif d'alimentation sous haute pression, ce qui constitue un ensemble plus simple que les ensembles traditionnels.
PCT/US1995/007074 1994-09-02 1995-06-02 Procede de cuisson continue de pate kraft avec pretraitement de la liqueur noire WO1996007786A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU26972/95A AU2697295A (en) 1994-09-02 1995-06-02 Continuous kraft cooking with black liquor pretreatment

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US29910394A 1994-09-02 1994-09-02
US299,103 1994-09-02

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Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1998032912A1 (fr) * 1997-01-22 1998-07-30 Ahlstrom Machinery Oy Cuisson discontinue avec pretraitement par liqueur noire
WO1998035090A1 (fr) * 1997-02-09 1998-08-13 Kvaerner Pulping Ab Procede continu de production de pate avec impregnation de liqueur residuaire
WO1998035091A1 (fr) * 1997-02-09 1998-08-13 Kvaerner Pulping Ab Procede et dispositif de cuisson continue de pate
WO1999007936A1 (fr) * 1997-08-07 1999-02-18 Ahlstrom Machinery, Inc. Cuisson en continu avec impregnation a faible temperature et reglage de la quantite de matiere organique dissoute (dom)
WO1999009243A1 (fr) * 1997-08-18 1999-02-25 Kvaerner Pulping Ab Cuisson de pate a papier comportant une concentration effective elevee en alcalis dans la phase residuelle
RU2472888C1 (ru) * 2011-10-18 2013-01-20 Открытое акционерное общество "Группа "Илим" Способ получения сульфатной целлюлозы из древесины лиственницы
RU2472889C1 (ru) * 2011-09-06 2013-01-20 Открытое акционерное общество "Группа "Илим" Способ экстракции щепы лиственницы
RU2475576C1 (ru) * 2011-09-06 2013-02-20 Открытое акционерное общество "Группа "Илим" Способ экстракции щепы лиственницы
RU2477346C1 (ru) * 2011-06-23 2013-03-10 ОАО "Группа "Илим" Способ получения сульфатной целлюлозы из древесины лиственницы
RU2490383C1 (ru) * 2012-04-19 2013-08-20 Открытое акционерное общество "Группа "Илим" Способ обработки смеси щепы из разных пород древесины перед сульфатной варкой
RU2491379C1 (ru) * 2012-04-19 2013-08-27 Открытое акционерное общество "Группа "Илим" Способ получения сульфатной целлюлозы из смеси щепы разных пород древесины
RU2493308C1 (ru) * 2012-04-19 2013-09-20 Открытое акционерное общество "Группа "Илим" Способ получения сульфитной целлюлозы из смеси щепы разных пород древесины
US8951388B2 (en) 2011-04-08 2015-02-10 Pec-Tech Engineering And Construction Pte Ltd Method and system for efficient production of dissolving pulp in a kraft mill producing paper grade pulp with a continuous type digester
RU2775961C1 (ru) * 2021-07-12 2022-07-12 Владимир Васильевич Галайко Способ проведения лабораторных физико-химических исследовательских процессов при получении целлюлозы

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0476230A2 (fr) * 1990-09-17 1992-03-25 Kamyr, Inc. Cuisson kraft complète avec lessive blanche ajoutée à la circulation de lavage
EP0477059A2 (fr) * 1990-09-20 1992-03-25 Kvaerner Pulping Technologies AB Imprégnation avec liqueur noire avant l'introduction de la liqueur blanche
EP0517689A1 (fr) * 1991-05-24 1992-12-09 Kamyr, Inc. Liqueurs avec quantités de sulfure à plusieurs niveaux

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0476230A2 (fr) * 1990-09-17 1992-03-25 Kamyr, Inc. Cuisson kraft complète avec lessive blanche ajoutée à la circulation de lavage
EP0477059A2 (fr) * 1990-09-20 1992-03-25 Kvaerner Pulping Technologies AB Imprégnation avec liqueur noire avant l'introduction de la liqueur blanche
EP0517689A1 (fr) * 1991-05-24 1992-12-09 Kamyr, Inc. Liqueurs avec quantités de sulfure à plusieurs niveaux

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US6350348B1 (en) 1997-01-22 2002-02-26 Andritz-Ahlstrom Oy Batch cooking with black liquor pretreatment
WO1998032912A1 (fr) * 1997-01-22 1998-07-30 Ahlstrom Machinery Oy Cuisson discontinue avec pretraitement par liqueur noire
WO1998035090A1 (fr) * 1997-02-09 1998-08-13 Kvaerner Pulping Ab Procede continu de production de pate avec impregnation de liqueur residuaire
WO1998035091A1 (fr) * 1997-02-09 1998-08-13 Kvaerner Pulping Ab Procede et dispositif de cuisson continue de pate
WO1999007936A1 (fr) * 1997-08-07 1999-02-18 Ahlstrom Machinery, Inc. Cuisson en continu avec impregnation a faible temperature et reglage de la quantite de matiere organique dissoute (dom)
US5958181A (en) * 1997-08-07 1999-09-28 Ahlstrom Machinery, Inc. Continuous cooking with a two-stage cool impregnation
WO1999009243A1 (fr) * 1997-08-18 1999-02-25 Kvaerner Pulping Ab Cuisson de pate a papier comportant une concentration effective elevee en alcalis dans la phase residuelle
US9574302B2 (en) 2011-04-08 2017-02-21 Rge Pte Ltd Method and system for efficient production of dissolving pulp in a kraft mill producing paper grade pulp with a continuous type digester
US8951388B2 (en) 2011-04-08 2015-02-10 Pec-Tech Engineering And Construction Pte Ltd Method and system for efficient production of dissolving pulp in a kraft mill producing paper grade pulp with a continuous type digester
RU2477346C1 (ru) * 2011-06-23 2013-03-10 ОАО "Группа "Илим" Способ получения сульфатной целлюлозы из древесины лиственницы
RU2472889C1 (ru) * 2011-09-06 2013-01-20 Открытое акционерное общество "Группа "Илим" Способ экстракции щепы лиственницы
RU2475576C1 (ru) * 2011-09-06 2013-02-20 Открытое акционерное общество "Группа "Илим" Способ экстракции щепы лиственницы
RU2472888C1 (ru) * 2011-10-18 2013-01-20 Открытое акционерное общество "Группа "Илим" Способ получения сульфатной целлюлозы из древесины лиственницы
RU2490383C1 (ru) * 2012-04-19 2013-08-20 Открытое акционерное общество "Группа "Илим" Способ обработки смеси щепы из разных пород древесины перед сульфатной варкой
RU2491379C1 (ru) * 2012-04-19 2013-08-27 Открытое акционерное общество "Группа "Илим" Способ получения сульфатной целлюлозы из смеси щепы разных пород древесины
RU2493308C1 (ru) * 2012-04-19 2013-09-20 Открытое акционерное общество "Группа "Илим" Способ получения сульфитной целлюлозы из смеси щепы разных пород древесины
RU2775961C1 (ru) * 2021-07-12 2022-07-12 Владимир Васильевич Галайко Способ проведения лабораторных физико-химических исследовательских процессов при получении целлюлозы

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ZA956633B (en) 1996-03-19

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