EP0698681A1 - Process for depithing pith containing plants, in particular sorghum - Google Patents

Process for depithing pith containing plants, in particular sorghum Download PDF

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Publication number
EP0698681A1
EP0698681A1 EP95202146A EP95202146A EP0698681A1 EP 0698681 A1 EP0698681 A1 EP 0698681A1 EP 95202146 A EP95202146 A EP 95202146A EP 95202146 A EP95202146 A EP 95202146A EP 0698681 A1 EP0698681 A1 EP 0698681A1
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EP
European Patent Office
Prior art keywords
section
twin
screws
plant
plant material
Prior art date
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EP95202146A
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German (de)
French (fr)
Inventor
Antoine Gaset
Christos Manolas
Jean-Paul Jamet
Luc Rigal
Senghane N'diaye
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.)
Sorgho Agro-Industriel Et Papetier Sais SA
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Sorgho Agro-Industriel Et Papetier Sais SA
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Publication of EP0698681A1 publication Critical patent/EP0698681A1/en
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B30—PRESSES
    • B30B—PRESSES IN GENERAL
    • B30B9/00—Presses specially adapted for particular purposes
    • B30B9/02—Presses specially adapted for particular purposes for squeezing-out liquid from liquid-containing material, e.g. juice from fruits, oil from oil-containing material
    • B30B9/12—Presses specially adapted for particular purposes for squeezing-out liquid from liquid-containing material, e.g. juice from fruits, oil from oil-containing material using pressing worms or screws co-operating with a permeable casing
    • B30B9/121—Screw constructions
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B30—PRESSES
    • B30B—PRESSES IN GENERAL
    • B30B9/00—Presses specially adapted for particular purposes
    • B30B9/02—Presses specially adapted for particular purposes for squeezing-out liquid from liquid-containing material, e.g. juice from fruits, oil from oil-containing material
    • B30B9/12—Presses specially adapted for particular purposes for squeezing-out liquid from liquid-containing material, e.g. juice from fruits, oil from oil-containing material using pressing worms or screws co-operating with a permeable casing
    • B30B9/16—Presses specially adapted for particular purposes for squeezing-out liquid from liquid-containing material, e.g. juice from fruits, oil from oil-containing material using pressing worms or screws co-operating with a permeable casing operating with two or more screws or worms
    • 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
    • D21B1/025—Separating pith from fibrous vegetable materials
    • 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
    • D21B1/30—Defibrating by other means
    • 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
    • D21C5/00—Other processes for obtaining cellulose, e.g. cooking cotton linters ; Processes characterised by the choice of cellulose-containing starting materials

Definitions

  • the invention relates to a process for dismantling annual marrow plants, such as fiber sorghum, with a view to obtaining fibers of paper quality ready to then undergo the conventional treatments making it possible to prepare pulp.
  • the invention proposes to provide a new process for dismantling marrow plants making it possible to obtain fibers of papermaking quality ready to undergo conventional papermaking treatments.
  • An objective of the invention is to reduce or even eliminate the loss of fibers which can be used in the paper process.
  • Another objective is to increase the quantity of fibrous materials of papermaking quality obtained, by preserving some of the components of the marrow which are usable in the papermaking process (only being eliminated the components which penalize the papermaking quality of the fibers).
  • the method of the invention proposes not only to eliminate the loss of fibers outside the marrow but also to conserve the part of the marrow which has been found not to penalize the paper quality of the fibers. obtained: in this way, in the case of sorghum, the process results in the conservation of 75% to 80% of the plant (taking into account the dissolution of certain protein and carbohydrate fractions).
  • the method of the invention combines (1) a mechanical treatment which is carried out by a worm device , in particular twin-screw device (known in itself) in conditions which are sufficiently mild to avoid defibrating the plant, with (2) a chemical treatment with soda or potash under specific conditions which are sufficiently gentle to eliminate that the penalizing components in particular hemicellulosic without delignification.
  • the mechanical treatment allows an access of the liquid reagent (soda, potash) towards the interior of the fibers by diffusion, an in situ solvation of the penalizing components, and a diffusion in opposite direction which ensures the extraction of the solution.
  • soda or potash has a solvation function but also a rheological function of plasticizer which protects the fibers during the mechanical treatment and guarantees zero or low defibration and therefore very low fiber losses.
  • the mechanical treatment allows the chemical treatment to operate at the heart of the fibers to solvate certain components, while the chemical treatment guarantees the execution of the mechanical treatment without significant defibration .
  • twin screw device of the type of those used in the invention are known in themselves and described in particular in the patents or certificates of addition FR 2 319 737 , FR 2 436 844, FR 2 418 295, FR 2 618 811.
  • These documents describe twin-screw devices which make it possible, in the paper industry, to process wood chips in order to obtain pulp. However, these devices are implemented under much more severe mechanical conditions so as to obtain defibration of the wood and insulation of the fibers with a view to making paper.
  • Certain documents indicate that chemical reagents can be added during the mechanical treatment, in particular bleaching reagents (conventional in the manufacture of paper pulps).
  • the patents FR 2 418 495 and FR 2 618 811 generally state that sodium hydroxide can be used as a reagent in order to dissolve the lignin (which requires a high concentration of sodium hydroxide).
  • the method of the invention uses such twin-screw devices but under very different conditions and for opposite objectives both mechanically and chemically: avoid defibrating the marrow plants, avoid solubilizing the lignin from so as to keep the fibers intact.
  • the method of the invention thus makes it possible to unravel marrow plants by eliminating the penalizing components, without significant defibration, or delignification, so as to provide a fibrous raw material capable of then undergoing paper treatments, whatever the type of these, to lead to good quality pulp and paper.
  • the contacting of the marrow plant with the basic solution is carried out by injecting the basic solution into the twin-screw device in the vicinity of the entry of the plant material. An excellent impregnation of the materials is thus obtained without prior operation outside the device. twin screw.
  • Such a device allows, by a combined treatment of mixing, kneading, expansion and compression, to fulfill the following functions under the best conditions: impregnation of the plant material with the solution, solvation of the penalizing components of the cord without defibration and separation of the liquid phase.
  • This device was created from modules distributed by the Company "CLEXTRAL” (registered trademark) under the reference “BC 45". Each module includes two identical co-penetrating screws and a tubular enclosure enveloping the two screws; this double wall enclosure allows thermal regulation.
  • the device comprises seven sections 1, 2, 3, 4, 5, 6 and 7, which are arranged one after the other along a horizontal axis.
  • the first section combines four direct pitch screw modules: module 8 of type T2F 66 (double thread trapezoidal, length 100 mm, positive pitch of 66 mm), module 9 of type C2F 55 (conjugated double thread screw, length 100 mm, positive pitch of 55), module 10 of type C2F 33 (double-threaded conjugate screw, length 100 mm, positive pitch of 33) and module 11 of type C2F 25 (double-threaded conjugated screw, length 100 mm, positive pitch of 25) .
  • the nomenclature used is the CLEXRAL nomenclature.
  • the screw threads of the modules decrease from the first to the fourth.
  • the length of this first section is approximately 0.28 times the total length of the device.
  • the plant material to be treated is introduced at the inlet 8a of the module 8.
  • the entry of the basic solution takes place at the level of the module 10 through a conduit 12 provided with a pump 13.
  • the second section 2 combines ten crossed bi-lobed disc modules of length 10 mm each, such as 14 of the MAL2 90 type (B).
  • the third section 3 combines three direct-pitch modules: module 15 of the C2F 33 type, module 16 of the C2F 33 type, module 17 of the C2F 25 type (these modules are identical respectively to the downstream modules 10 and 11 of the section 1).
  • the fourth section 4 combines ten kneading modules, each formed by a kneading disc of length 10 mm each, such as 18 of type MAL ⁇ (DM).
  • the fifth section 5 is identical to the section 3, but provided with a liquid outlet 19 provided with a filter 20.
  • the sixth section 6 comprises a module 21 of inverted-pitch screws, of the CFC type type (counter-thread, length 100 mm, negative pitch of 25 mm).
  • the seventh section 7 comprises a module 22 of direct pitch screw of the C2F 25 type.
  • the output of the treated plant materials takes place at the output 22a of this module.
  • the various modules are rotated in the same direction and at the same speed by an electric motor 23 making it possible to obtain a screw rotation speed of up to 600 rpm.
  • Temperature sensors are arranged along the device allowing knowledge of the average temperatures for the following parts of the device: sensor 24 for modules 8 and 9, sensor 25 for modules 10 and 11, sensor 26 for modules 14 and 15, sensor 27 for modules 16 and 17, sensor 28 for module 18 and the first module of section 5, sensor 29 for the second and third modules of section 5, and sensor 30 for modules 21 and 22; in addition, a measurement of the electric current consumed by the motor is carried out during the tests in order to provide a relative indication of the intensity of the mechanical work undergone by the material.
  • fiber sorghum previously cut with a hammer mill equipped with a 2 cm grid is used.
  • the cutting is carried out only to facilitate the introduction into the system of sorghum which contains 90% of dry matter.
  • the twin-screw device is that described above.
  • the dry matter extrudate / dry matter input ratio is 79%. This constitutes a considerable advantage compared to other demoelling techniques.
  • the paper fiber yield of 79% is 75% higher compared to the yields by mechanical demoulding which is around 45%.
  • the fiber sorghum used in this example has the same characteristics and the same composition as that of Example 1.
  • the twin-screw device is the same as that of Example 1.
  • the dry matter / extrudate / dry matter input ratio is 82%.
  • the papermaking fiber yield is 82% higher compared to the yields by conventional demoulding.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Wood Science & Technology (AREA)
  • Paper (AREA)

Abstract

To remove the pith from plant matter the material is treated with a watery solution of soda or potassium in a ratio of base:plant matter of 0.02-0.5 g OH<->/g dry plant material. The wt. dilution of liquid/dry plant material is 1-10. The consistent mixture is treated mechanically for compression and shearing in a continuous screw which has forwards and reverse screw pitch sections. The screw action is at temps. less than 100 degrees C in a gentle action, for liquid penetration through the plant material without damage. The fibre material, without pith, is obtained by pressing out the liquid.

Description

L'invention concerne un procédé de démoellage de plantes annuelles à moelle, telles que le sorgho à fibres, en vue d'obtenir des fibres de qualité papetière prêtes à subir ensuite les traitements classiques permettant de préparer des pâtes à papier.The invention relates to a process for dismantling annual marrow plants, such as fiber sorghum, with a view to obtaining fibers of paper quality ready to then undergo the conventional treatments making it possible to prepare pulp.

On sait que certains papiers sont préparés à partir de plantes annuelles et notamment de plantes à moelle telles que le sorgho à fibres, de façon à réduire la consommation de bois dans la fabrication du papier et à fournir un débouché pour ces plantes annuelles dont la production est importante et qui ne peuvent plus être totalement utilisées dans la filière alimentaire traditionnelle.It is known that certain papers are prepared from annual plants and in particular from marrow plants such as fiber sorghum, so as to reduce the consumption of wood in the manufacture of paper and to provide an outlet for these annual plants whose production is important and can no longer be fully used in the traditional food chain.

Le démoellage de ces plantes est une opération nécessaire car on a pu constater que l'utilisation des plantes complètes conduisait à des pâtes à papier de mauvaise qualité. Actuellement, cette opération de démoellage est effectuée par un traitement mécanique de broyage des plantes, suivi d'une séparation par densité de la moelle (plus légère que les autres composants de la plante). Le défaut connu de ce type de démoellage est qu'il élimine, en même temps que la moelle, une proportion importante des fibres de la plante. Par exemple, dans le sorgho, la moelle représente en poids environ 15 à 20 % de l'ensemble et le démoellage traditionnel élimine environ 45 à 55 % de la plante : une proportion notable de la plante correspondant à des fibres utilisables est ainsi perdue.The dismantling of these plants is a necessary operation because it has been observed that the use of whole plants leads to poor quality paper pulp. Currently, this demolding operation is carried out by a mechanical grinding treatment of the plants, followed by separation by density of the marrow (lighter than the other components of the plant). The known defect of this type of demoelling is that it eliminates, at the same time as the marrow, a significant proportion of the fibers of the plant. For example, in sorghum, the marrow represents by weight approximately 15 to 20% of the whole and the traditional dismantling eliminates approximately 45 to 55% of the plant: a significant proportion of the plant corresponding to usable fibers is thus lost.

L'invention se propose de fournir un nouveau procédé de démoellage de plantes à moelle permettant d'obtenir des fibres de qualité papetière prêtes à subir les traitements papetiers classiques.The invention proposes to provide a new process for dismantling marrow plants making it possible to obtain fibers of papermaking quality ready to undergo conventional papermaking treatments.

Un objectif de l'invention est de réduire, voire de supprimer la perte des fibres utilisables dans le processus papetier.An objective of the invention is to reduce or even eliminate the loss of fibers which can be used in the paper process.

Un autre objectif est d'accroître la quantité de matières fibreuses de qualité papetière obtenue, en conservant certains des composants de la moelle qui sont utilisables dans le processus papetier (seuls étant éliminés les composants qui pénalisent la qualité papetière des fibres).Another objective is to increase the quantity of fibrous materials of papermaking quality obtained, by preserving some of the components of the marrow which are usable in the papermaking process (only being eliminated the components which penalize the papermaking quality of the fibers).

Ainsi, dans le cas du sorgho à fibres, le procédé de l'invention se propose non seulement de supprimer la perte des fibres hors moelle mais encore de conserver la partie de la moelle qui s'est avérée ne pas pénaliser la qualité papetière des fibres obtenues : de la sorte, dans le cas du sorgho, le procédé conduit à conserver de 75 % à 80 % de la plante (compte tenu de la dissolution de certaines fractions protéiques et glucidiques).Thus, in the case of fiber sorghum, the method of the invention proposes not only to eliminate the loss of fibers outside the marrow but also to conserve the part of the marrow which has been found not to penalize the paper quality of the fibers. obtained: in this way, in the case of sorghum, the process results in the conservation of 75% to 80% of the plant (taking into account the dissolution of certain protein and carbohydrate fractions).

Le procédé de démoellage conforme à l'invention pour éliminer des plantes à moelle les composants pénalisants à l'obtention ultérieure de pâte papetière de bonne qualité, est caractérisé en ce que :

  • on met en contact la plante à moelle avec une solution aqueuse basique de soude ou de potasse de sorte que le ratio base/matière végétale soit compris entre 0,02 et 0,5 équivalent gramme OH⁻ par gramme de matière végétale sèche, et que le rapport pondéral de dilution liquide/matière végétale sèche soit compris entre 1 et 10,
  • on soumet le mélange hétérogène obtenu à un traitement mécanique de compression et cisaillement au moyen d'un dispositif à vis sans fin, pourvu de vis à pas direct et de vis à pas inversé, ledit traitement mécanique étant réalisé a une température inférieure à 100° C dans des conditions douces propres à assurer une diffusion du liquide dans la matière végétale sans réaliser un défibrage sensible de ladite matière végétale,
  • on sépare par pressage la matière fibreuse démoellée de la phase liquide.
The demolding procedure according to the invention for eliminating from the marrow plants the penalizing components in the subsequent obtaining of good quality paper pulp, is characterized in that:
  • the marrow plant is brought into contact with a basic aqueous solution of soda or potash so that the base / plant material ratio is between 0.02 and 0.5 gram equivalent OH⁻ per gram of dry plant material, and the liquid dilution / dry vegetable matter weight ratio is between 1 and 10,
  • the heterogeneous mixture obtained is subjected to a mechanical compression and shearing treatment by means of a worm device, provided with direct pitch screws and reverse pitch screws, said mechanical treatment being carried out at a temperature below 100 ° C under mild conditions suitable for ensuring diffusion of the liquid in the plant material without producing substantial defibration of said plant material,
  • the demolished fibrous material is pressed off from the liquid phase.

Les essais ont démontré que le procédé ci-dessus décrit n'attaque pas sensiblement les fibres de la tige des plantes en raison de leur insolubilité dans le milieu basique et de la nature douce du traitement mécanique : on évite ainsi une perte de ces fibres. En outre, les inventeurs ont mis en évidence que la moelle des plantes comporte généralement une proportion notable de fibres utiles pour fabriquer les pâtes à papier : le procédé de l'invention conserve cette fraction et élimine uniquement les composants pénalisants. Une étude a montré que ces composants pénalisants étaient essentiellement constitués par des hémicelluloses et certains composants minoritaires tels que protéines, glucides libres ... Le procédé de l'invention combine (1) un traitement mécanique qui est effectué par un dispositif à vis sans fin, en particulier dispositif bi-vis (connu en lui-même) dans des conditions suffisamment douces pour ne pas défibrer la plante, avec (2) un traitement chimique à la soude ou à la potasse dans des conditions spécifiques suffisamment douces pour n'éliminer que les composants pénalisants notamment hemicellulosiques sans délignification. Le traitement mécanique permet un accès du réactif liquide (soude, potasse) vers l'intérieur des fibres par diffusion, une solvatation in situ des composants pénalisants, et une diffusion en sens inverse qui assure l'extraction de la solution. Il a été constaté que la soude ou la potasse présente une fonction de solvatation mais également une fonction rhéologique de fluidifiant qui protège les fibres pendant le traitement mécanique et garantit un défibrage nul ou faible et donc de très faibles pertes de fibres. Il y a ainsi étroite synergie entre le traitement chimique et le traitement mécanique : le traitement mécanique permet au traitement chimique d'opérer au coeur des fibres pour en solvater certains composants, cependant que le traitement chimique garantit l'exécution du traitement mécanique sans défibrage notable.The tests have demonstrated that the process described above does not significantly attack the fibers of the stem of plants because of their insolubility in the basic environment and the gentle nature of the mechanical treatment: this avoids loss of these fibers. In addition, the inventors have demonstrated that the plant marrow generally contains a significant proportion of fibers useful for making paper pulp: the method of the invention retains this fraction and eliminates only the penalizing components. A study has shown that these penalizing components are essentially constituted by hemicelluloses and certain minority components such as proteins, free carbohydrates ... The method of the invention combines (1) a mechanical treatment which is carried out by a worm device , in particular twin-screw device (known in itself) in conditions which are sufficiently mild to avoid defibrating the plant, with (2) a chemical treatment with soda or potash under specific conditions which are sufficiently gentle to eliminate that the penalizing components in particular hemicellulosic without delignification. The mechanical treatment allows an access of the liquid reagent (soda, potash) towards the interior of the fibers by diffusion, an in situ solvation of the penalizing components, and a diffusion in opposite direction which ensures the extraction of the solution. It has been found that soda or potash has a solvation function but also a rheological function of plasticizer which protects the fibers during the mechanical treatment and guarantees zero or low defibration and therefore very low fiber losses. There is thus a close synergy between the chemical treatment and the mechanical treatment: the mechanical treatment allows the chemical treatment to operate at the heart of the fibers to solvate certain components, while the chemical treatment guarantees the execution of the mechanical treatment without significant defibration .

Il est à noter que les dispositifs à vis sans fin, en particulier dispositif bi-vis, du type de ceux utilisés dans l'invention sont connus en eux-mêmes et décrits en particulier dans les brevets ou certificats d'addition FR 2 319 737, FR 2 436 844, FR 2 418 295, FR 2 618 811. Ces documents décrivent des dispositifs bi-vis qui permettent, dans la filière papetière, de traiter des copeaux de bois en vue d'obtenir de la pâte à papier. Cependant, ces dispositifs sont mis en oeuvre dans des conditions beaucoup plus sévères sur le plan mécanique de façon à obtenir un défibrage du bois et un isolement des fibres en vue de fabriquer le papier. Certains documents indiquent que des réactifs chimiques peuvent être ajoutés au cours du traitement mécanique, en particulier des réactifs de blanchiment (classiques dans la fabrication des pâtes à papier). Les brevets FR 2 418 495 et FR 2 618 811 mentionnent d'une façon générale que la soude peut être utilisée comme réactif en vue de solubiliser la lignine, (ce qui exige une concentration de soude élevée). Le procédé de l'invention utilise de tels dispositifs bi-vis mais dans des conditions très différentes et pour des objectifs opposés aussi bien sur le plan mécanique que sur le plan chimique : éviter de défibrer les plantes à moelle, éviter de solubiliser la lignine de façon à conserver intactes les fibres. Le procédé de l'invention permet ainsi de démoeller les plantes à moelle par une élimination des composants pénalisants, sans défibrage notable, ni délignification, de façon à fournir une matière première fibreuse apte à subir ensuite des traitements papetiers, quel que soit le type de ceux-ci, pour conduire à des pâtes à papier et à des papiers de bonne qualité.It should be noted that the worm devices, in particular twin screw device, of the type of those used in the invention are known in themselves and described in particular in the patents or certificates of addition FR 2 319 737 , FR 2 436 844, FR 2 418 295, FR 2 618 811. These documents describe twin-screw devices which make it possible, in the paper industry, to process wood chips in order to obtain pulp. However, these devices are implemented under much more severe mechanical conditions so as to obtain defibration of the wood and insulation of the fibers with a view to making paper. Certain documents indicate that chemical reagents can be added during the mechanical treatment, in particular bleaching reagents (conventional in the manufacture of paper pulps). The patents FR 2 418 495 and FR 2 618 811 generally state that sodium hydroxide can be used as a reagent in order to dissolve the lignin (which requires a high concentration of sodium hydroxide). The method of the invention uses such twin-screw devices but under very different conditions and for opposite objectives both mechanically and chemically: avoid defibrating the marrow plants, avoid solubilizing the lignin from so as to keep the fibers intact. The method of the invention thus makes it possible to unravel marrow plants by eliminating the penalizing components, without significant defibration, or delignification, so as to provide a fibrous raw material capable of then undergoing paper treatments, whatever the type of these, to lead to good quality pulp and paper.

Les expérimentations ont montré que les meilleurs résultats étaient obtenus en utilisant une solution aqueuse de soude telle que le ratio soude/matière végétale soit compris entre 0,05 et 0,1 équivalent gramme OH⁻ par gramme de matière végétale sèche et que le rapport pondéral de dilution soit compris entre 3 et 5.Experiments have shown that the best results were obtained using an aqueous soda solution such that the soda / plant material ratio is between 0.05 and 0.1 gram equivalent OH⁻ per gram of dry plant material and that the weight ratio dilution is between 3 and 5.

Selon un mode de mise en oeuvre préféré, la mise en contact de la plante à moelle avec la solution basique est effectuée en injectant la solution basique dans le dispositif bi-vis au voisinage de l'entrée de la matière végétale. On obtient ainsi une excellente imprégnation des matières sans opération préalable en dehors du dispositif bi-vis.According to a preferred embodiment, the contacting of the marrow plant with the basic solution is carried out by injecting the basic solution into the twin-screw device in the vicinity of the entry of the plant material. An excellent impregnation of the materials is thus obtained without prior operation outside the device. twin screw.

On utilise avantageusement un dispositif bi-vis comportant :

  • un premier tronçon comprenant des vis à pas direct, au niveau duquel la solution basique est injectée, les vis de ce tronçon étant adaptées pour réaliser une imprégnation de la matière végétale et un cheminement de celle-ci,
  • un deuxième tronçon comprenant des disques bilobes, adapté pour assurer un premier traitement mécanique de la matière au contact de la solution basique,
  • un troisième tronçon comprenant des vis à pas direct, adapté pour permettre une expansion de la matière à la sortie du deuxième tronçon,
  • un quatrième tronçon comprenant des disques de malaxage, adapté pour assurer un deuxième traitement mécanique de la matière végétale, en particulier plus intense que le premier traitement,
  • un cinquième tronçon comprenant des vis à pas direct, adapté pour permettre une expansion de la matière à la sortie du quatrième tronçon, la séparation de la phase liquide étant assurée par soutirage à travers un filtre dans la zone terminale de ce cinquième tronçon,
  • un sixième tronçon comprenant au moins une vis à pas inversé, adapté pour assurer une compression de la matière végétale,
  • un septième tronçon comprenant au moins une vis à pas direct pour assurer la sortie de la matière du dispositif bi-vis.
Advantageously, a twin-screw device is used comprising:
  • a first section comprising direct pitch screws, at the level of which the basic solution is injected, the screws of this section being suitable for impregnating the plant material and routing it,
  • a second section comprising bi-lobed discs, adapted to provide a first mechanical treatment of the material in contact with the basic solution,
  • a third section comprising direct pitch screws, adapted to allow an expansion of the material at the outlet of the second section,
  • a fourth section comprising kneading discs, suitable for ensuring a second mechanical treatment of the plant material, in particular more intense than the first treatment,
  • a fifth section comprising direct-pitch screws, adapted to allow an expansion of the material at the outlet of the fourth section, the separation of the liquid phase being ensured by drawing off through a filter in the end zone of this fifth section,
  • a sixth section comprising at least one screw with inverted pitch, adapted to ensure compression of the plant material,
  • a seventh section comprising at least one direct pitch screw to ensure the exit of the material from the twin-screw device.

Un tel dispositif permet, par un traitement combiné de mélange, malaxage, expansion et compression, de remplir les fonctions suivantes dans les meilleures conditions : imprégnation de la matière végétale avec la solution, solvatation des composants pénalisants de la moelle sans défibrage et séparation de la phase liquide.Such a device allows, by a combined treatment of mixing, kneading, expansion and compression, to fulfill the following functions under the best conditions: impregnation of the plant material with the solution, solvation of the penalizing components of the cord without defibration and separation of the liquid phase.

Les caractéristiques suivantes du dispositif bi-vis contribuent à optimiser le résultat obtenu :

  • le premier tronçon est composé de plusieurs vis de pas différents, plus faibles vers l'aval, le troisième et le cinquième tronçons étant composés de vis dont les pas sont voisins du pas des vis aval du premier tronçon,
  • le rapport de la longueur totale des tronçons à pas direct (première, troisième, cinquième, septième) à la longueur du sixième tronçon à pas inversé est compris entre 6 et 22,
  • le premier tronçon est de longueur supérieure au quart de la longueur totale du dispositif.
The following characteristics of the twin-screw device help to optimize the result obtained:
  • the first section is made up of several screws with different pitches, smaller downstream, the third and fifth sections being made up of screws whose pitches are close to the pitch of the downstream screws of the first section,
  • the ratio of the total length of the direct pitch sections (first, third, fifth, seventh) to the length of the sixth reverse pitch section is between 6 and 22,
  • the first section is longer than a quarter of the total length of the device.

Le procédé de l'invention peut en particulier être appliqué pour le démoellage du sorgho à fibres en vue de son traitement ultérieur dans la filière papetière. Les conditions suivantes semblent être les meilleures pour cette plante :

  • température comprise entre 40° C et 70° C,
  • débit massique de matière vegétale compris entre 0,2 et 0,6 kg/heure de matière sèche par cm² de section libre du dispositif bi-vis (par "section libre", on entend la section moyenne disponible pour le passage des matières),
  • temps de séjour de la matière végétale dans le dispositif bi-vis comprise entre 30 s et 250 s.
The process of the invention can in particular be applied for the demotelling of fiber sorghum with a view to its subsequent treatment in the paper industry. The following conditions seem to be the best for this plant:
  • temperature between 40 ° C and 70 ° C,
  • mass flow of plant material of between 0.2 and 0.6 kg / hour of dry matter per cm² of free section of the twin-screw device (by "free section" is meant the average section available for the passage of materials),
  • residence time of the plant material in the twin-screw device between 30 s and 250 s.

Les exemples qui suivent sont destinés à illustrer le procédé de l'invention. Ils ont été mis en oeuvre au moyen d'un dispositif bi-vis tel que représenté aux dessins :

  • la figure 1 est une représentation longitudinale symbolique du dispositif,
  • la figure 2 en est une coupe transversale.
The examples which follow are intended to illustrate the process of the invention. They were implemented by means of a twin-screw device as shown in the drawings:
  • FIG. 1 is a symbolic longitudinal representation of the device,
  • Figure 2 is a cross section.

Ce dispositif a été constitué à partir de modules distribués par la Société "CLEXTRAL" (marque déposée) sous la référence "BC 45". Chaque module comprend deux vis identiques copénétrantes et une enceinte tubulaire enveloppant les deux vis ; cette enceinte à double paroi permet une régulation thermique.This device was created from modules distributed by the Company "CLEXTRAL" (registered trademark) under the reference "BC 45". Each module includes two identical co-penetrating screws and a tubular enclosure enveloping the two screws; this double wall enclosure allows thermal regulation.

Le dispositif comprend sept tronçons 1, 2, 3, 4, 5, 6 et 7, qui sont disposés les uns à la suite des autres le long d'un axe horizontal.The device comprises seven sections 1, 2, 3, 4, 5, 6 and 7, which are arranged one after the other along a horizontal axis.

Le premier tronçon combine quatre modules de vis à pas direct : module 8 du type T2F 66 (trapézoïdale double filet, longueur 100 mm, pas positif de 66 mm), module 9 du type C2F 55 (vis conjuguée double filet, longueur 100 mm, pas positif de 55), module 10 du type C2F 33 (vis conjuguée double filet, longueur 100 mm, pas positif de 33) et module 11 du type C2F 25 (vis conjuguée double-filet, longueur 100 mm, pas positif de 25). La nomenclature utilisée est la nomenclature CLEXRAL. Les pas de vis des modules décroissent du premier au quatrième. La longueur de ce premier tronçon est d'environ 0,28 fois la longueur totale du dispositif.The first section combines four direct pitch screw modules: module 8 of type T2F 66 (double thread trapezoidal, length 100 mm, positive pitch of 66 mm), module 9 of type C2F 55 (conjugated double thread screw, length 100 mm, positive pitch of 55), module 10 of type C2F 33 (double-threaded conjugate screw, length 100 mm, positive pitch of 33) and module 11 of type C2F 25 (double-threaded conjugated screw, length 100 mm, positive pitch of 25) . The nomenclature used is the CLEXRAL nomenclature. The screw threads of the modules decrease from the first to the fourth. The length of this first section is approximately 0.28 times the total length of the device.

La matière végétale à traiter est introduite à l'entrée 8a du module 8. L'entrée de la solution basique s effectue au niveau du module 10 par un conduit 12 doté d'une pompe 13.The plant material to be treated is introduced at the inlet 8a of the module 8. The entry of the basic solution takes place at the level of the module 10 through a conduit 12 provided with a pump 13.

Le deuxième tronçon 2 combine dix modules de disques bilobes croisés de longueur de 10 mm chacun, tel que 14 de type MAL₂ 90 (B).The second section 2 combines ten crossed bi-lobed disc modules of length 10 mm each, such as 14 of the MAL₂ 90 type (B).

Le troisième tronçon 3 combine trois modules à pas direct : module 15 du type C2F 33, module 16 du type C2F 33, module 17 du type C2F 25 (ces modules sont identiques respectivement aux modules aval 10 et 11 du tronçon 1).The third section 3 combines three direct-pitch modules: module 15 of the C2F 33 type, module 16 of the C2F 33 type, module 17 of the C2F 25 type (these modules are identical respectively to the downstream modules 10 and 11 of the section 1).

Le quatrième tronçon 4 combine dix modules de malaxage, chacun formé par un disque de malaxage de longueur de 10 mm chacun, tel que 18 de type MAL φ (DM).The fourth section 4 combines ten kneading modules, each formed by a kneading disc of length 10 mm each, such as 18 of type MAL φ (DM).

Le cinquième tronçon 5 est identique au tronçon 3, mais doté d'une sortie de liquide 19 pourvue d'un filtre 20.The fifth section 5 is identical to the section 3, but provided with a liquid outlet 19 provided with a filter 20.

Le sixième tronçon 6 comprend un module 21 de vis à pas inversé, de type CFC₂ (contre-filet, longueur 100 mm, pas négatif de 25 mm).The sixth section 6 comprises a module 21 of inverted-pitch screws, of the CFC type type (counter-thread, length 100 mm, negative pitch of 25 mm).

Le septième tronçon 7 comprend un module 22 de vis à pas direct de type C₂F 25. La sortie des matières végétales traitées s'opère à la sortie 22a de ce module.The seventh section 7 comprises a module 22 of direct pitch screw of the C₂F 25 type. The output of the treated plant materials takes place at the output 22a of this module.

Les divers modules sont entraînés en rotation dans le même sens et à même vitesse par un moteur électrique 23 permettant d'obtenir une vitesse de rotation de vis pouvant atteindre 600 tours/min.The various modules are rotated in the same direction and at the same speed by an electric motor 23 making it possible to obtain a screw rotation speed of up to 600 rpm.

Des capteurs de température sont disposés le long du dispositif permettant une connaissance des températures moyennes pour des parties suivantes du dispositif : capteur 24 pour les modules 8 et 9, capteur 25 pour les modules 10 et 11, capteur 26 pour les modules 14 et 15, capteur 27 pour les modules 16 et 17, capteur 28 pour le module 18 et le premier module du tronçon 5, capteur 29 pour le deuxième et le troisième modules du tronçon 5, et capteur 30 pour les modules 21 et 22 ; en outre une mesure de l'intensité électrique consommée par le moteur est effectuée au cours des essais en vue de fournir une indication relative de l'intensité du travail mécanique subi par la matière.Temperature sensors are arranged along the device allowing knowledge of the average temperatures for the following parts of the device: sensor 24 for modules 8 and 9, sensor 25 for modules 10 and 11, sensor 26 for modules 14 and 15, sensor 27 for modules 16 and 17, sensor 28 for module 18 and the first module of section 5, sensor 29 for the second and third modules of section 5, and sensor 30 for modules 21 and 22; in addition, a measurement of the electric current consumed by the motor is carried out during the tests in order to provide a relative indication of the intensity of the mechanical work undergone by the material.

EXEMPLE 1 : EXAMPLE 1 :

Dans cet exemple, on utilise du sorgho à fibres préalablement découpé avec un broyeur à marteaux équipé d'une grille de 2 cm. Le découpage n'est effectué que pour faciliter l'introduction dans le dispositif du sorgho qui contient 90 % de matière sèche.In this example, fiber sorghum previously cut with a hammer mill equipped with a 2 cm grid is used. The cutting is carried out only to facilitate the introduction into the system of sorghum which contains 90% of dry matter.

Le dispositif bi-vis est celui décrit précédemment.The twin-screw device is that described above.

Les conditions particulières dans cet exemple sont les suivantes :

  • Vitesse de rotation de vis : 150 tr/min.,
  • Débit de matière : 0,37 kg/h par cm² de section libre,
  • Ratio soude/matière végétale : 0,18,
  • Débit de solution basique de soude : 1,47 kg/h par cm² de section libre.
  • Les températures de chaque capteur 24-30 sont présentées au Tableau 1 en °C.
TABLEAU 1 Températures des tronçons 24-30 Capteur 24 25 26 27 28 29 30 Température 47 61 60 55 60 60 55 - L'énergie électrique consommée par le moteur : 1420 Watt. The specific conditions in this example are as follows:
  • Screw rotation speed: 150 rpm.,
  • Material flow: 0.37 kg / h per cm² of free section,
  • Soda / vegetable matter ratio: 0.18,
  • Flow rate of basic sodium hydroxide solution: 1.47 kg / h per cm² of free section.
  • The temperatures of each 24-30 sensor are presented in Table 1 in ° C.
TABLE 1 Section temperatures 24-30 Sensor 24 25 26 27 28 29 30 Temperature 47 61 60 55 60 60 55 - The electrical energy consumed by the motor: 1420 Watt.

Le rapport matière sèche extrudat/matière sèche entrée est de 79 %. Ceci constitue un avantage considérable par rapport aux autres techniques de démoellage. Le rendement en fibre papetière de 79 % est supérieur de 75 % par rapport aux rendements par démoellage mécanique qui est de l'ordre de 45 %.The dry matter extrudate / dry matter input ratio is 79%. This constitutes a considerable advantage compared to other demoelling techniques. The paper fiber yield of 79% is 75% higher compared to the yields by mechanical demoulding which is around 45%.

Les caractéristiques physiques des pâtes obtenues par le procédé SPROOT WALDON mesurées à 50° SR sont décrites au Tableau 2. TABLEAU 2 Caractéristiques physiques des pâtes obtenues après démoellage Volume massique (cm³/g) Longueur de rupture (m) Indice d'éclatement (Kpa.m²/g) Indice de déchirement (m.Nm²/g) Concora medium Test Ring Crush Test 1,55 4810 2,06 450 171 174 The physical characteristics of the doughs obtained by the SPROOT WALDON process measured at 50 ° SR are described in Table 2. TABLE 2 Physical characteristics of the pasta obtained after demoulding Mass volume (cm³ / g) Breaking length (m) Burst index (Kpa.m² / g) Tear index (m.Nm² / g) Concora medium Test Ring Crush Test 1.55 4810 2.06 450 171 174

EXEMPLE 2 : EXAMPLE 2 :

Le sorgho à fibres utilisé au cours de cet exemple a les mêmes caractéristiques et la même composition que celui de l'exemple 1.The fiber sorghum used in this example has the same characteristics and the same composition as that of Example 1.

Le dispositif bi-vis est le même que celui de l'exemple 1.The twin-screw device is the same as that of Example 1.

Les conditions particulières dans cet exemple sont les suivantes :

  • Vitesse de rotation de vis : 150 tr/min.,
  • Débit de matière : 0,34 kg/h par cm² de section libre,
  • Débit de solution basique de soude : 1,51 kg/h par cm² de section libre,
  • Ratio soude/matière végétale : 0,16,
  • Les températures de chaque capteur 24-30 sont présentées au Tableau 3.
TABLEAU 3 Températures des tronçons 24-30 Capteur 24 25 26 27 28 29 30 Température 41 52 52 47 52 51 52 - L'énergie électrique consommée par le moteur : 1640 Watt. The specific conditions in this example are as follows:
  • Screw rotation speed: 150 rpm.,
  • Material flow: 0.34 kg / h per cm² of free section,
  • Flow rate of basic sodium hydroxide solution: 1.51 kg / h per cm² of free section,
  • Soda / vegetable matter ratio: 0.16,
  • The temperatures of each 24-30 sensor are shown in Table 3.
TABLE 3 Section temperatures 24-30 Sensor 24 25 26 27 28 29 30 Temperature 41 52 52 47 52 51 52 - The electrical energy consumed by the motor: 1640 Watt.

Le rapport matière sèche extrudat/matière sèche entrée est de 82 %. Le rendement en fibre papetière est supérieur de 82 % par rapport aux rendements par démoellage classique.The dry matter / extrudate / dry matter input ratio is 82%. The papermaking fiber yield is 82% higher compared to the yields by conventional demoulding.

Les caractéristiques physiques des pâtes obtenues par le procédé SPROOT WALDON mesurées à 50° SR sont décrites au Tableau 4. TABLEAU 4 Caractéristiques physiques des pâtes obtenues après démoellage Volume massique (cm³/g) Longueur de rupture (m) Indice d'éclatement (Kpa.m²/g) Indice de déchirement (m.Nm²/g) Concora medium Test Ring Crush Test 1,44 4960 2,03 357 177 180 The physical characteristics of the doughs obtained by the SPROOT WALDON process measured at 50 ° SR are described in Table 4. TABLE 4 Physical characteristics of the pasta obtained after demoulding Mass volume (cm³ / g) Breaking length (m) Burst index (Kpa.m² / g) Tear index (m.Nm² / g) Concora medium Test Ring Crush Test 1.44 4960 2.03 357 177 180

Claims (9)

Procédé de démoellage de plantes à moelle en vue d'obtenir des fibres de qualité papetière prêtes à subir les traitements classiques de préparation de pâtes à papier, caractérisé en ce que : - on met en contact la plante à moelle avec une solution aqueuse basique de soude ou de potasse de sorte que le ratio base/matière végétale soit compris entre 0,02 et 0,5 équivalent gramme OH⁻ par gramme de matière végétale sèche, et que le rapport pondéral de dilution liquide/matière végétale sèche soit compris entre 1 et 10, - on soumet le mélange hétérogène obtenu à un traitement mécanique de compression et cisaillement au moyen d'un dispositif à vis sans fin, pourvu de vis à pas direct et de vis à pas inversé, ledit traitement mécanique étant réalisé à une température inférieure à 100° C dans des conditions douces propres à assurer une diffusion du liquide dans la matière végétale sans réaliser un défibrage sensible de cette dernière, - on sépare par pressage la matière fibreuse démoellée de la phase liquide. Process for dismantling marrow plants in order to obtain paper quality fibers ready to undergo the conventional treatments for preparing paper pulp, characterized in that: the marrow plant is brought into contact with a basic aqueous solution of soda or potassium hydroxide so that the base / plant material ratio is between 0.02 and 0.5 gram equivalent OH⁻ per gram of dry plant material, and the liquid dilution / dry vegetable matter weight ratio is between 1 and 10, - The heterogeneous mixture obtained is subjected to a mechanical compression and shearing treatment by means of a worm device, provided with direct pitch screws and reverse pitch screws, said mechanical treatment being carried out at a temperature below 100 ° C under mild conditions suitable for ensuring diffusion of the liquid in the plant material without carrying out substantial defibration of the latter, - The demolished fibrous material is pressed off from the liquid phase. Procédé selon la revendication 1, dans lequel la plante à moelle est mise en contact avec une solution aqueuse de soude avec un ratio soude/matière végétale compris entre 0,05 et 0,1 équivalent gramme OH⁻ par gramme de matière végétale sèche et un rapport pondéral de dilution compris entre 3 et 5.Process according to Claim 1, in which the marrow plant is brought into contact with an aqueous soda solution with a soda / plant material ratio of between 0.05 and 0.1 gram equivalent OH⁻ per gram of dry plant matter and a weight ratio of dilution between 3 and 5. Procédé selon l'une des revendications 1 ou 2, dans lequel la mise en contact de la plante à moelle avec la solution basique est effectuée en injectant la solution basique dans le dispositif bi-vis au voisinage de l'entrée de la matière végétale.Method according to one of claims 1 or 2, wherein the contacting of the marrow plant with the basic solution is carried out by injecting the basic solution into the twin-screw device in the vicinity of the entry of the plant material. Procédé selon la revendication 3, dans lequel on utilise un dispositif bi-vis comportant : - un premier tronçon comprenant des vis à pas direct, au niveau duquel la solution basique est injectée, les vis de ce tronçon étant adaptées pour réaliser une imprégnation de la matière végétale, et un cheminement de celle-ci, - un deuxième tronçon comprenant des disques bilobes, adapté pour assurer un premier traitement mécanique de la matière au contact de la solution basique, - un troisième tronçon comprenant des vis à pas direct, adapté pour permettre une expansion de la matière à la sortie du deuxième tronçon, - un quatrième tronçon comprenant des disques de malaxage, adapté pour assurer un deuxième traitement mécanique de la matière végétale, - un cinquième tronçon comprenant des vis à pas direct, adapté pour permettre une expansion de la matière à la sortie du quatrième tronçon, la séparation de la phase liquide étant assurée par soutirage à travers un filtre dans la zone terminale de ce cinquième tronçon, - un sixième tronçon comprenant au moins une vis à pas inversé, adapté pour assurer une compression de la matière végétale, - un septième tronçon comprenant au moins une vis à pas direct pour assurer la sortie de la matière du dispositif bi-vis. Method according to claim 3, in which a twin-screw device is used comprising: a first section comprising direct pitch screws, at which the basic solution is injected, the screws of this section being adapted to impregnate the plant material, and a path of it, a second section comprising bi-lobed discs, adapted to provide a first mechanical treatment of the material in contact with the basic solution, a third section comprising direct pitch screws, adapted to allow an expansion of the material at the outlet of the second section, a fourth section comprising kneading discs, adapted to ensure a second mechanical treatment of the plant material, a fifth section comprising screws with direct pitch, adapted to allow an expansion of the material at the outlet of the fourth section, the separation of the liquid phase being ensured by drawing off through a filter in the end zone of this fifth section, a sixth section comprising at least one screw with inverted pitch, adapted to ensure compression of the plant material, - A seventh section comprising at least one direct pitch screw to ensure the exit of the material from the twin-screw device. Procédé selon la revendication 4, dans lequel on utilise un dispositif bi-vis dont le premier tronçon est composé de plusieurs vis de pas différents, décroissants vers l'aval, le troisième et le cinquième tronçons étant composés de vis dont les pas sont voisins du pas des vis aval du premier tronçon.Method according to claim 4, in which a twin-screw device is used, the first section of which is composed of several screws of different pitches, decreasing downstream, the third and fifth sections being composed of screws whose pitches are close to the not downstream screws of the first section. Procédé selon l'une des revendications 4 ou 5, dans lequel on utilise un dispositif bi-vis dont le rapport de la longueur totale des tronçons à pas direct (première, troisième, cinquième, septième) à la longueur du tronçon à pas inversé est compris entre 6 et 22.Method according to one of claims 4 or 5, in which a twin-screw device is used, the ratio of the total length of the direct pitch sections (first, third, fifth, seventh) to the length of the reverse pitch section is between 6 and 22. Procédé selon l'une des revendications 4, 5 ou 6, dans lequel on utilise un dispositif bi-vis dont le premier tronçon est de longueur supérieure au quart de la longueur totale du dispositif.Method according to one of claims 4, 5 or 6, in which a twin-screw device is used, the first section of which is greater than a quarter of the total length of the device. Procédé selon l'une des revendications 4, 5 6 ou 7, pour le démoellage du sorgho à fibres, caractérisé en ce que le traitement mécanique dans le dispositif bi-vis est réalisé dans les conditions suivantes : - température comprise entre 40° C et 60° C, - débit massique de matière vegétale compris entre 0,2 et 0,6 kg/heure de matière sèche par cm² de section du dispositif bi-vis, - temps de séjour de la matière végétale dans le dispositif bi-vis comprise entre 30 s et 250 s. Method according to one of claims 4, 5 6 or 7, for the demottling of fiber sorghum, characterized in that the mechanical treatment in the twin-screw device is carried out under the following conditions: - temperature between 40 ° C and 60 ° C, - mass flow of vegetable matter between 0.2 and 0.6 kg / hour of dry matter per cm² of cross-section of the twin-screw device, - residence time of the plant material in the twin-screw device between 30 s and 250 s. Procédé selon la revendication 8, dans lequel on utilise un dispositif bi-vis réalisé à partir de modules comprenant chacun deux vis identiques copénétrantes disposées dans une enceinte tubulaire à double paroi, les vis étant amenées à tourner à une vitesse de rotation comprise entre 120 et 230 tours/minute.Method according to claim 8, in which a twin-screw device is used, made from modules each comprising two identical co-penetrating screws arranged in a double-walled tubular enclosure, the screws being made to rotate at a speed of rotation of between 120 and 230 rpm.
EP95202146A 1994-08-10 1995-08-07 Process for depithing pith containing plants, in particular sorghum Withdrawn EP0698681A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR9409978A FR2723598B1 (en) 1994-08-10 1994-08-10 PROCESS FOR DEMOELLING MARINE PLANTS, ESPECIALLY SORGHO, IN ORDER TO OBTAIN PAPER QUALITY FIBERS
FR9409978 1994-08-10

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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0785218A3 (en) * 1996-01-16 1998-06-03 Green Group S.r.L. Method for making industrial products from agricultural raw materials either containing or not starch
FR2758344A1 (en) * 1997-01-16 1998-07-17 Ardeval Champagne Ardenne PROCESS FOR FRACTIONING STRAW OF CEREALS, IN PARTICULAR WHEAT AND BARLEY
CN100347374C (en) * 2005-08-30 2007-11-07 天津科技大学 Fibre detaching apparatus with high shearing
WO2008031862A2 (en) * 2006-09-13 2008-03-20 Freeland Horticulture Limited Apparatus and process for the treatment of plant waste to produce growing media
EP3120995A1 (en) * 2015-07-20 2017-01-25 Talleres Mercier, S.A. Double-flighted thread pulp press screws

Citations (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR601621A (en) * 1924-11-05 1926-03-05 Manufacture of mechanical pulp with maritime pine and other resin tree species
FR1133056A (en) * 1956-04-23 1957-03-20 Production and uses of sorghum celluloses for the manufacture of paper and agglomerates
DE2047807A1 (en) * 1970-08-07 1972-04-06 Beloit Corp., Beloit, Wis. (V.St.A.) Digestions process for bagasse
JPS49134901A (en) * 1973-05-01 1974-12-25
FR2319737A1 (en) 1975-07-31 1977-02-25 Creusot Loire PAPER PULP MANUFACTURING PROCESS AND MACHINE
FR2418295A1 (en) 1978-02-27 1979-09-21 Creusot Loire METHOD AND INSTALLATION FOR THE CONTINUOUS PROCESSING OF A CELLULOSIC MATERIAL
FR2418495A1 (en) 1978-02-27 1979-09-21 Rockwell International Corp POWER SUPPLY OF A COMPUTING DEVICE WITH DATA PROTECTION IN THE EVENT OF A POWER INTERRUPTION
FR2436844A2 (en) 1978-09-19 1980-04-18 Creusot Loire Converting lignocellulose material into fibre pulp - for paper-making, by introducing bleach whilst the lignocellulose is being broken down
JPS5876589A (en) * 1981-08-13 1983-05-09 エンソ−グツトゼイト・オ−ワイ Production of paper pulp from bagasse
FR2556376A1 (en) * 1983-12-13 1985-06-14 Yhtyneet Paperitehtaat Oy Process for producing refined milled wood pulp
FR2618811A1 (en) 1987-07-31 1989-02-03 Centre Tech Ind Papier Process for the manufacture of bleached chemimechanical or chemithermal mechanical pulps
WO1989007169A1 (en) * 1988-02-05 1989-08-10 Beghin-Say, S.A. Process for removing the fibre from a lignocellulose material
US4857145A (en) * 1987-07-13 1989-08-15 Process Evaluation And Development Corporation Process for making a pulp from bamboo
US4997488A (en) * 1988-02-05 1991-03-05 The United States Of America As Represented By The Secretary Of Agriculture Combined physical and chemical treatment to improve lignocellulose digestibility

Patent Citations (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR601621A (en) * 1924-11-05 1926-03-05 Manufacture of mechanical pulp with maritime pine and other resin tree species
FR1133056A (en) * 1956-04-23 1957-03-20 Production and uses of sorghum celluloses for the manufacture of paper and agglomerates
FR69564E (en) * 1956-04-23 1958-11-10 Production and uses of sorghum celluloses for the manufacture of paper and agglomerates
DE2047807A1 (en) * 1970-08-07 1972-04-06 Beloit Corp., Beloit, Wis. (V.St.A.) Digestions process for bagasse
JPS49134901A (en) * 1973-05-01 1974-12-25
FR2319737A1 (en) 1975-07-31 1977-02-25 Creusot Loire PAPER PULP MANUFACTURING PROCESS AND MACHINE
FR2418295A1 (en) 1978-02-27 1979-09-21 Creusot Loire METHOD AND INSTALLATION FOR THE CONTINUOUS PROCESSING OF A CELLULOSIC MATERIAL
FR2418495A1 (en) 1978-02-27 1979-09-21 Rockwell International Corp POWER SUPPLY OF A COMPUTING DEVICE WITH DATA PROTECTION IN THE EVENT OF A POWER INTERRUPTION
FR2436844A2 (en) 1978-09-19 1980-04-18 Creusot Loire Converting lignocellulose material into fibre pulp - for paper-making, by introducing bleach whilst the lignocellulose is being broken down
JPS5876589A (en) * 1981-08-13 1983-05-09 エンソ−グツトゼイト・オ−ワイ Production of paper pulp from bagasse
FR2556376A1 (en) * 1983-12-13 1985-06-14 Yhtyneet Paperitehtaat Oy Process for producing refined milled wood pulp
US4857145A (en) * 1987-07-13 1989-08-15 Process Evaluation And Development Corporation Process for making a pulp from bamboo
FR2618811A1 (en) 1987-07-31 1989-02-03 Centre Tech Ind Papier Process for the manufacture of bleached chemimechanical or chemithermal mechanical pulps
WO1989007169A1 (en) * 1988-02-05 1989-08-10 Beghin-Say, S.A. Process for removing the fibre from a lignocellulose material
US4997488A (en) * 1988-02-05 1991-03-05 The United States Of America As Represented By The Secretary Of Agriculture Combined physical and chemical treatment to improve lignocellulose digestibility

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
CHEMICAL ABSTRACTS, vol. 82, no. 26, 30 June 1975, Columbus, Ohio, US; abstract no. 172891A, WATANABE S.: "paper pulps from graminaceous grasses" page 110; column R; *
ENSO-GUTZEIT OY: "Pulp Manufacture from Bagasse", ABSTRACT BULLETIN OF THE INSTITUTE OF PAPER CHEMISTRY, vol. 55, no. 1, APPLETON, WI, USA, pages 134 *

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0785218A3 (en) * 1996-01-16 1998-06-03 Green Group S.r.L. Method for making industrial products from agricultural raw materials either containing or not starch
FR2758344A1 (en) * 1997-01-16 1998-07-17 Ardeval Champagne Ardenne PROCESS FOR FRACTIONING STRAW OF CEREALS, IN PARTICULAR WHEAT AND BARLEY
WO1998031871A1 (en) * 1997-01-16 1998-07-23 Ardeval Champagne Ardenne Method for fractionating cereal straw, in particular wheat and barley
CN100347374C (en) * 2005-08-30 2007-11-07 天津科技大学 Fibre detaching apparatus with high shearing
WO2008031862A2 (en) * 2006-09-13 2008-03-20 Freeland Horticulture Limited Apparatus and process for the treatment of plant waste to produce growing media
WO2008031862A3 (en) * 2006-09-13 2008-10-09 Freeland Horticulture Ltd Apparatus and process for the treatment of plant waste to produce growing media
EP3120995A1 (en) * 2015-07-20 2017-01-25 Talleres Mercier, S.A. Double-flighted thread pulp press screws

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FR2723598A1 (en) 1996-02-16
FR2723598B1 (en) 1996-10-18

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