CH328444A

CH328444A - Process for the manufacture of sheets of fibrous material, apparatus for carrying out this process and product obtained by this process

Info

Publication number: CH328444A
Authority: CH
Inventors: James Thomas Reginald
Original assignee: St Annes Board Mill Co Ltd
Priority date: 1954-07-23
Filing date: 1955-07-22
Publication date: 1958-03-15

Description

Procede pour Ja fabrication de feuilles de mauere fibreuse, appareil pour la mise en aeuvre de ce procede et produit obtenu par ce procede La presente invention a pour objet un-pro- ced6 pour la fabrication de feuilles de matiere fibreuse ä partir dune päte fibreuse aqueuse supportee par une Bande transporteuse en mouvement. Process for the manufacture of sheets of fibrous material, apparatus for implementing this process and product obtained by this process The subject of the present invention is a process for the manufacture of sheets of fibrous material from an aqueous fibrous pulp. supported by a moving conveyor belt.

Dans 1e brevet suisse No 321893 an a de- crit un tel procede. Selon ce dernier, an appli- que une Pression sur la päte ä Papier mouillee au moyen d'un organe de Pressage permeable mobile au-dessus de ladite Bande, de maniere ä ecraser la päte ä Papier mouillee pour en se- parer 1'eau, une Partie au moins de 1'eau s6pa- ree s'ecoulant ä travers 1'organe de Pressage et etant äliminee par 1e haut sous 1'action de moyens pneumatiques, 1'effet de moulage ou de feutrage sur la päte ä Papier etant partiellement dü ä 1'organe de Pressage. In Swiss Patent No. 321893 an has described such a process. According to the latter, pressure is applied to the wet pulp by means of a permeable pressing member movable above said strip, so as to crush the wet pulp to separate the water therefrom. , at least part of the separated water flowing through the pressing member and being removed from the top under the action of pneumatic means, the molding or felting effect on the pulp being partially due to the pressing device.

L'expression extraction de 1'eau telle qu'utilisee dans la presente description a la si- gnification suivante : 1'extraction initiale de 1'eau de la päte ä Papier reduit sa teneur en eau de maniäre ä former une pike d'un tissu pratiquement continu. La teneur resultante en solides fournit une concentration. de fibres qui oblige celles-ci ä s'entrelacer et ä former une structure qui reste pratiquement inalteree par la suite. Cet etat de la päte ä-papier est compris dans l'expression de päte moulee qui est utilisee dans la presente description. De 1'eau est encore eliminee de la päte ä Papier moulee par divers procedes connus, par exemple au moyen de boites d'aspiration, d'un rouleau Presseur et de presses humides, cette päte etant finalement sechee et Passant sous forme de Bande continue autour de cylindres de sechage. . The term water extraction as used in this description has the following meaning: the initial extraction of water from the pulp reduces its water content so as to form a pike of a practically continuous fabric. The resulting solids content provides a concentration. of fibers which forces them to intertwine and form a structure which remains practically unaltered thereafter. This state of the pulp is included in the expression molded pulp which is used in the present description. Water is further removed from the molded pulp by various known methods, for example by means of suction boxes, pressure roll and wet presses, this pulp being finally dried and Passing in the form of a continuous Web. around drying cylinders. .

Le brevet susmentionne decrit egalement un appareil pour la mise en Oeuvre du procede de- fini ci-dessus, cet appareil comprenant un Or gane de Pressage permeable dispose au-dessus dune bange transporteuse et agence de ma- niere ä se deplacer avec elle en vue d'ecraser la couche de päte ä Papier non moulee et d'en se- parer 1'eau, et des moyens pour eliminer 1'eau separee qui passe vers 1e haut ä travers ledit Organe, ces moyens etant pneumatiques. The aforementioned patent also describes an apparatus for carrying out the process defined above, this apparatus comprising a permeable Pressing Body placed above a conveyor belt and arranged so as to move with it in sight. crushing the unmolded pulp layer and separating water therefrom, and means for removing separated water which passes upwardly through said member, said means being pneumatic.

Le but principal de la presente invention est de fournir un procede et un appareil per fectionn6s pour l'elimination vers le haut de 1'eau separee. The primary object of the present invention is to provide an improved method and apparatus for the upward removal of separated water.

Le procede faisant 1'objet de la presente In- vention est caractärise en ce qu'on restreint le libre ecoulement de la päte fibreuse en condui- sant celle-ci au-dessous dune piece permeable superieure se depla@ant avec la Bande et for- mant avec cette derniere un Intervalle pr6sen- tant d'abord une seetion decroissante, dans la- quelle se forme une pappe de päte, puis une section constante, dans laquelle la päte est pressee pour en s6parer 1'eau, en ce qu'on fait passer Feau depuis ladite pappe ä travers la section decroissänte et en ce qu'on fait passer de Fair sur la surface superieure de Feau afin de Fentrainer et de faciliter son passalte et son retrait, de maniere ä obtenir un effet de feu- trage sur la päte partiellement dü ä ladite pike permeable superieure. L'appareil faisant agalement Fobjet de I'in- vention pour la mise en Oeuvre de ce procede, est caraeterise en ce qu'il comprend une pike perm6able disposde au-dessus dune Bande por- teuse en mouvement et se deplagant avec cette derniere, des moyens pour amener la pike per meable superieure ä proximith de la Bande de maniere ä former entre elles un intervalle pr6- sentant d'abord une section decroissante puis une section constante servant ä presser la päte aqueuse pour en s6parer 1'eau, lesdits moyens agissant aussi pour restreindre 1'ecoulement de la päte et former une pappe au tra vers de la Bande ä partir de laquelle Feau passe ä travers ladite section decroissante, des moyens pour produire un courant d'air sur la surface superieure de Feau pour Fentrainer et favori- ser son passalte et son retrait, et une voie d'eau dirigee vers 1'arriere et vers 1e bas disposee dans la trajectoire dudit courant, la disposition etant telle que Feau entrainee est portee 1e long de cette voie d'eau au sommet de laquelle elle s'ecoule, pour favoriser la formation au moins partielle dune couche sur la piece permeable. Un dispositif d'aspiration est dispose de preference au-dessus de Forgane permeable pour augmenter 1e courant d'eau ä travers cet Organe et Famener sous Finfluence du courant d'air. L'organe permeable est de prdference en ferm6 dans la region oü 1e courant d'air agit pour entrainer Feau, et des fentes sont m6na- g6es dans cette enceinte pour permettre d'as- pirer Fair ä travers la surface de Feau. Le dessin annexe represente, ä titre d'exem- ple, une forme d'execution de Fappareil objet de Finvention. La fig. 1 en est une vue laterale. The method forming the subject of the present invention is characterized in that the free flow of the fibrous pulp is restricted by leading the latter below an upper permeable part moving with the Strip and forming - forming with the latter an Interval presenting first a decreasing section, in which a pappe of dough is formed, then a constant section, in which the dough is pressed to separate the water, in that the water is passed from said pappe through the decreasing section and in that air is passed over the upper surface of the water in order to train it and facilitate its passing and removal, so as to obtain a felting effect. on the dough partially due to said upper permeable pike. The apparatus which is also the subject of the invention for the implementation of this method, is characterized in that it comprises a permeable pike placed above a carrier strip in motion and moving with the latter, means for bringing the upper permeable pike close to the Strip so as to form between them an interval having first a decreasing section then a constant section serving to press the aqueous paste to separate the water therefrom, said means also acting to restrict the flow of the dough and form a puff across the Strip from which the water passes through said decreasing section, means for producing an air current on the upper surface of the water to entrain and promote its passage and retreat, and a backward and downwardly directed waterway disposed in the path of said current, the arrangement being such that entrained water is carried along such waterway at the top from which it flows, to promote at least partial formation of a layer on the permeable part. A suction device is preferably arranged above the permeable member to increase the flow of water through this member and reduce it under the influence of the air current. The permeable member is preferably enclosed in the region where the air current acts to entrain water, and slots are provided in this enclosure to allow air to be drawn through the surface of the water. The appended drawing shows, by way of example, one form of execution of the apparatus which is the subject of the invention. fig. 1 is a side view.

La fig. 2 est une vue en plan selon la ligne 2-2 de la fig. 1. fig. 2 is a plan view along line 2-2 of FIG. 1.

La fig. 3 est une coupe d'un cylindre d'ap- proche et d'un mecanisme d'extraction d'eau. La fig. 4 est une vue prise depuis la gauche de la fig. 3. La fig. 5 est une vue semblable ä la fig. 3 montrant RTI ID="0002.0270" WI="19" HE="3" LX="1408" LY="627"> 1'dcoulement de Fair dans la zone du cylindre d'approche. La fig. 6 est une vue en plan correspondant ä la fig. 5. Les fig. 1 et .2 ne representent que les par- ties n6cessaires ä la description de la presente invention. L'appareil @representd comprend des rouleaux de support 1 dune Bande transpor- teuse 2, des rouleaux de pression 3 et 4, et un bäti 5 portant un certain nombre de blocs 6 pour 1e montage des rouleaux 1. 11 est sup- pose agir sur une couche de päte ä papier dejä trait6e par un appareil prec6dent, d'oü provient la Bande 2. Un cadre 7 comprend des moyens de montage du rouleau 3, des rouleaux de gui- dage 9, 10 et 11 et d'un cylindre d'approche 8 recouvert d'un tissu metallique et mont6 ä ro- tation sur des consoles 41, 42 (visibles ä la fig. 4). fig. 3 is a section of an approach cylinder and a water extraction mechanism. fig. 4 is a view taken from the left of FIG. 3. Fig. 5 is a view similar to fig. 3 showing RTI ID="0002.0270" WI="19" HE="3" LX="1408" LY="627"> Fair flow in the area of the approach cylinder. fig. 6 is a plan view corresponding to fig. 5. Figs. 1 and 2 represent only the parts necessary for the description of the present invention. The apparatus shown comprises supporting rollers 1 of a conveyor belt 2, pressure rollers 3 and 4, and a frame 5 carrying a number of blocks 6 for mounting the rollers 1. on a layer of paper pulp already treated by a previous apparatus, from which the strip 2 originates. approach 8 covered with a metal fabric and rotatably mounted on brackets 41, 42 (visible in FIG. 4).

Des rouleaux 12 et 13 guident 1e brin de retour de la Bande transporteuse 2. Rollers 12 and 13 guide the return side of conveyor belt 2.

Une boite de päte ä papier 14 est montee au-dessus de la Bande 2 de maniere que la päte sortant de la boite s'ecoule sous forme dune couche decouverte sur cette Bande, des re- bords 15, 16 empechant la päte ä papier de se repandre de cöte. Les moyens de montage de la boite 14 et des rebords 15, 16 ne sont pas representis. A box of pulp 14 is mounted above the Strip 2 so that the pulp exiting the box flows as an uncovered layer on this Strip, flanges 15, 16 preventing the pulp from spread sideways. The means for mounting the box 14 and the flanges 15, 16 are not represented.

Une courte Bande sans fin 19, en tissu me- tallique, est disposee autour du cylindre 8 et des rouleaux 3, 10 et 9, de maniere que son brin inferieur 20 soit pratiquement parallele ä la Bande transporteuse 2, 1e cylindre d'approche 8 etant place au-dessus de la Bande de ma- niere ä laisser un jeu entre sa peripherie et la- dite Bande 2. Une boite 21 est fixde au moyen de consoles 17, 18 au bäti horizontal 5. A par- tir de la Partie arriere de cette boite s'dtend une gouttiere 22 vers 1'arriere et vers 1e bas, en di- rection de la surface sup6rieure du brin inf6rieur 20 de la Bande 19. La gouttiere s'dtend sur toute la largeur de ce brin 20 et son Bord libre fait devier la Bande 19 et presse celle-ci ferme- ment vers 1e bas pour pincer ensemble 1e tissu mdtallique et la Bande de maniere ä diviser 1e brin infdrieur 20 en deux sections. Une section 23 s'6tend de la periph6rie du cylindre d'ap- proche 8 au Bord libre de la gouttiere 22, cette section formant un Petit angle avec la Bande transporteuse 2, de 4 degres .par exem- ple, tandis que 1'autre section 24 s'etend depuis ledit Bord libre jusqu'au rouleau de Pression 3 et est pratiquement parallele ä la Bande trans- porteuse. Il existe donc en fait une entree 44 en forme de coin entre 1e tissu m6tallique et la Bande transporteuse dans laquelle la päte se d6place et passe en direction de la section 24, une Pression vers 1e bas 6tant ainsi appli- quee ä la couche de päte qui a pour effet d'ex- primer 1'eau de la päte de bois. Cette entrde 44 est design6e ci-apres par 1'expression coin de Pression . A short endless belt 19, made of metal fabric, is arranged around the cylinder 8 and the rollers 3, 10 and 9, so that its lower side 20 is practically parallel to the conveyor belt 2, the approach cylinder 8 being placed above the Strip so as to leave a clearance between its periphery and the said Strip 2. A box 21 is fixed by means of consoles 17, 18 to the horizontal frame 5. rear of this box extends a gutter 22 rearward and downward, in the direction of the upper surface of the lower strand 20 of the Band 19. The gutter extends over the entire width of this strand 20 and its free edge deflects Band 19 and presses it firmly downward to pinch the metal fabric and Band together so as to divide the lower strand 20 into two sections. A section 23 extends from the periphery of the approach cylinder 8 to the free edge of the gutter 22, this section forming a small angle with the conveyor belt 2, of 4 degrees for example, while the Another section 24 extends from said Free Edge to Pressure Roller 3 and is substantially parallel to the Conveyor Belt. There is therefore in effect a wedge-shaped inlet 44 between the metal fabric and the conveyor belt in which the dough moves and passes in the direction of the section 24, downward pressure thus being applied to the layer of dough. which has the effect of expressing water from the wood pulp. This input 44 is designated below by the expression pressure wedge.

Comme an 1e voit ä la fig. 3, la gouttiere 22 est fix6e au Bord inferieur 25 dune fente 26 m6nag6e Jans une paroi arriere 27 de la boite 21, et une levre 28 s'etend depuis 1e Bord su- perieur de cette fente, vers 1'arriere et parallele- ment ä la glissiere 22. La gouttiere 22 et la le- vre 28 sont reunies sur leurs cöt6s de maniere ä former une gouttiere tubulaire de section rectangulaire 35, s'6tendant vers 1'arriere et vers 1e bas depuis la boite 21. Un Plateau 29 incline vers 1e haut se projette depuis la paroi arriere de la boite 21 et s'6tend sur toute la lar- geur de la section 23 de la Bande. Un ruban de caoutchouc 30 est fixe au Bord libre du Pla teau 29 et agence pour frotter contre la surface du cylindre d'approche B. 0n peut voir que 1e Plateau inclin6 29 et 1e ruban 30 forment en- semble un couvercle s'etendant depuis la paroi arriere de la boite 21 vers la Peripherie du cy- lindre d'approche B. Des parois 31 et 32 (voir fig. 2), qui partent du couvercle 29, 30 vers la section 23 du tissu mdtalhque, constituent des parois laterales enfermant la zone oü se trouve la pike permeable, zone situee entre la paroi arriere de la boite 21 et la p6ripherie du cylin- dre d'approche B. Ces parois lat6rales forment chacune un jeu 34 entre cette periph6rie et leur Bord arriere. Cette zone est soumise ä 1'in- fluence d'un courant d'air, comme an 1e <RTI ID="0003.0275" WI="8" HE="4" LX="1587" LY="413"> verra plus tard. As seen in fig. 3, the gutter 22 is attached to the lower edge 25 of a slot 26 formed in a rear wall 27 of the box 21, and a lip 28 extends from the upper edge of this slot, towards the rear and parallel to it. to the slide 22. The gutter 22 and the lip 28 are joined at their sides so as to form a tubular gutter of rectangular section 35, extending rearward and downward from the box 21. A Tray 29 The upward slope projects from the rear wall of the box 21 and extends the full width of the strip section 23. A rubber band 30 is attached to the Free Edge of Platen 29 and arranged to rub against the surface of approach cylinder B. It can be seen that the inclined Platen 29 and the band 30 together form a cover extending from the rear wall of box 21 towards the periphery of approach cylinder B. enclosing the area where the permeable pike is located, an area located between the rear wall of the box 21 and the periphery of the approach cylinder B. These side walls each form a clearance 34 between this periphery and their rear edge. This area is subject to the influence of an air current, as an <RTI ID="0003.0275" WI="8" HE="4" LX="1587" LY="413"> will see. later.

L'extremitd superieure de la boite 21 com- munique par un tuyau 33 avec un ventilateur (non represente) qui assure un courant ä haute vitesse d'air ä basse Pression ä travers les jeux 34, la surface de la section 23 et la section 35 de la gouttiere. Un second tuyau 47 dirige 1'eau vers un ecoulement. Une boite d'aspiration 36 est dispos6e ä 1'interieur du cylindre d'appro- che 8 recouvert du tissu m6tallique, et cette boite communique par des tuyaux 37, 38, 39 et 40 avec une source d'aspiration, dans un but qui Sera exposd plus bas. The upper end of the box 21 communicates via a pipe 33 with a fan (not shown) which provides a high velocity flow of low pressure air through the clearances 34, the surface of the section 23 and the cross section. 35 from the gutter. A second pipe 47 directs the water to a drain. A suction box 36 is disposed within the approach cylinder 8 covered with the metal fabric, and this box communicates through pipes 37, 38, 39 and 40 with a source of suction, for the purpose which Will be exposed below.

La . courte Bande mdtallique sans fin 19, conjointement ä la gouttiere 22, constitue une pike de Pression permeable mobile superieure, agencee pour presser la couche de päte de Pa pier mouill6e afin d'en s6parer 1'eau. There . The short endless metal strip 19, together with the gutter 22, constitutes an upper mobile permeable pressure pike, arranged to press the layer of wet paper pulp in order to separate the water therefrom.

L'appareil fonctionne de la maniere sui- vante La Bande transporteuse 2 est mise en mouvement et, par frottement, entrame la cour- te Bande saus fin metallique 19. Une aspiration est appliqude ä la boite 36 et 1e ventilateur de la boite 21 est mis en marche. The apparatus operates as follows. Conveyor belt 2 is set in motion and frictionally engages the short metal endless belt 19. Suction is applied to box 36 and the box fan 21 is turned on. started.

L'appareil represente aux fig. 1 et 2 est un appareil destind ä 1'extraction d'eau, c'est une couche de päte de Papier dejä moulee qui est deplac6e par la Bande 2 au-delä de la bohe 14. The apparatus shown in Figs. 1 and 2 is an apparatus intended for the extraction of water, it is a layer of pulp of paper already molded which is moved by the Belt 2 beyond the bohe 14.

L'alimentation de la päte est assuree par un tuyau 43 dans la boite 14, la päte s'dcou- lant sous forme de päte mouillee sur la couche moulde portee par la Bande 2, et les couches combin6es sont amendes au-dessous du cylin- dre d'approche 8 qui forme 1'entree du coin de Pression 44. The supply of the paste is ensured by a pipe 43 in the box 14, the paste flowing in the form of wet paste on the molded layer carried by the Belt 2, and the combined layers are fine below the cylinder. - approach dre 8 which forms the entrance to the pressure corner 44.

En cette Position, la päte ä Papier tend ä Former une nappe turbulente 45 qui est soumise ensuite ä_ 1'aspiration assur6e par la bo3te 36, celle-ci attirant 1'eau ä travers la section 23 de la bande. Il se produit ainsi au niveau du coin de Pression 44 une separation de 1'eau de la päte de Papier, cette Bau Passant vers 1e haut ä. travers la section 23, Faspiration de la boite 36 accentuant la separation'et favorisant 1'ecou- lement de Feau. Un peu d'eau est absorbee par la couche inferieure. L'eau ainsi s6par6e de la päte de Papier et qui passe vers 1e haut ä travers la section 23 tombe alors sous l'influence du courant d'air qui entre par les jeux 34. Un peu d'air entre aussi ä travers 1e cylindre B. La direction du courant d'air dass la zone du cylindre 8 est clairement montree sur les fig. 5 et 6.. Les fk- ches 4 & indiquent Fair Passant dann le cylindre et hors de celui-ci, et les- fleches 49 indiquent Fair entrant dans les jeux 34. Cet air entra?ne Feau separee et la Porte vers Fembouchure 35 de la gouttiere, Feau s'6coulant ä 1'interieur de la boite 21 d'oü elle est eliminee ou reprise pour etre utilisee ä nouveau. Par ce moyen, la päte se forme presque entierement sur la bande 19 et ainsi Feffet de formation ou de feutrage est principalement dü ä 1'organe de Pressage. In this position, the pulp tends to form a turbulent sheet 45 which is then subjected to the suction provided by the box 36, this drawing water through the section 23 of the belt. There is thus produced at the level of the pressure wedge 44 a separation of the water from the paper pulp, this Bau Passing upwards ä. through section 23, the suction of the box 36 accentuating the separation and favoring the flow of water. Some water is absorbed by the bottom layer. The water thus separated from the pulp and which passes upwards through the section 23 then falls under the influence of the current of air which enters through the gaps 34. A little air also enters through the cylinder. B. The direction of the air stream in the area of cylinder 8 is clearly shown in Figs. 5 and 6.. Arrows 4 & indicate Air Passing into and out of the cylinder, and arrows 49 indicate Air entering Games 34. This air carries the separated Water and the Gate towards the Mouth 35 from the gutter, the water flowing inside the box 21 from where it is eliminated or taken up to be used again. By this means, the dough forms almost entirely on the belt 19 and thus the forming or felting effect is mainly due to the pressing member.

Le procede decrit se rapporte ä. 1'extraction de Feau. Quand le proeede est destine ä la formation dune Premiere couche de päte, une Proportion considerable de Feau sdparee passe vers 1e bas ä travers la bande transporteuse. En fait; la moitie environ de 1'eau passe probable- ment vers le bas, et Fautre moitie vers 1e haut sous 1'action du courant d'air. Il faut remar- quer que dans ce cas, 1e courant d'air favorise la formation partielle de la couche de päte vers 1e haut, tandis qu'une Partie de la couche est form6e vers le bas gräce 'a la bande transpor- teuse. The process described relates to. water extraction. When the process is intended for the formation of a first layer of dough, a considerable proportion of the separated water passes downwards through the conveyor belt. Actually; about half of the water probably passes downwards, and the other half upwards under the action of the air current. It should be noted that in this case the air current favors the partial formation of the layer of dough upwards, while part of the layer is formed downwards thanks to the conveyor belt.

0n peut remarquer que trois facteurs con- tribuent ä 1'elimination de Feau vers le haut la boite d'aspiration 3,6, le courant d'air,ä haute vitesse et basse Pression, et l'ecoulement de la päte ä Papier dont la quantite de mouvement est ddterminee par la vitesse de la bande trans- porteuse 2. It can be seen that three factors contribute to the removal of water upwards from the suction box 3.6, the air stream, at high speed and low pressure, and the flow of pulp, of which the amount of movement is determined by the speed of conveyor belt 2.

L'appareil decrit s'est montre avantageux dans nombre de cas pour extraire Feau vers 1e haut dune couche decouverte de päte ä Papier mouill & , car il permet un contröle serre de 1'ecoulement d'eau vers 1e haut. Ainsi, en mo- difiant la force d'äspiration de la boite 36 et la vitesse du courant d'air, an peut facilement faire vagier 1'ecoulement, pour differentes vi- tesses de la bande 2 et differentes consistances de la päte. The disclosed apparatus has proven advantageous in many cases for extracting water upwards from an exposed layer of wet paper pulp, as it allows tight control of the upward flow of water. Thus, by varying the suction force of the box 36 and the speed of the air stream, one can easily vary the flow, for different speeds of the belt 2 and different consistencies of the dough.

L'appareil represente comprend encore une gouttiere inclinee 46 (fig. 1) dopt 1e bord est RTI ID="0004.0273" WI="9" HE="4" LX="1271" LY="625"> dirig6 vers la päte ä Papier et qui constitue une autre voie d'eau et contribue ä l'dlimination de Bette Bau vers le haut. The apparatus represented further comprises an inclined gutter 46 (FIG. 1) whose first edge is RTI ID="0004.0273" WI="9" HE="4" LX="1271" LY="625"> directed towards the dough ä Paper and which constitutes another waterway and contributes to the elimination of Bette Bau upwards.

Claims

CLAIM I Process for the manufacture of sheets of fibrous material from an aqueous fibrous pulp supported by a moving conveyor belt, characterized in that the free flow of the fibrous pulp is restricted by leading it below a upper permeable piece moving with the belt and forming with the latter a gap having first a decreasing section, in which a sheet of dough is formed, then a constant section, in which the dough is pressed to separate the water therefrom, in that the water is made to pass from the said sheet through the decreasing section, and in that air is made to pass over the upper surface of the water in order to entrain it and facilitate its passage and its shrinkage, so as to obtain a felting effect on the dough partly due to said upper permeable piece. CLAIM 1I Apparatus for carrying out the method according to claim I, characterized in that it comprises a permeable pike arranged above a moving carrier strip and i moving with the latter, means for bringing the upper permeable pike near the strip so as to form between them an interval having first a decreasing section then a constant section, serving to press the aqueous paste to separate the water therefrom, the said means also acting to restrict the flow of the dough and form a sheet across the strip from which water passes through said decreasing section, means for producing an air current on the upper surface of the water to entrain it and promote its passage and its withdrawal, and a backward and downwardly directed waterway arranged in the path of said current, the arrangement being such that the water in train is carried along this waterway at the top from which it flows, to promote at least partial formation of a layer on the permeable pike. CLAIM III Product obtained by the process according to claim I. SUB-CLAIMS 1. Apparatus according to claim II, characterized in that it comprises a suction device placed above the said permeable organ to increase the current of water through this organ and thus place it under the influence of the current of air.

2. Apparatus according to claim 11, characterized in that said permeable member is enclosed in a zone in which the air current acts to entrain the water, slots being provided in this zone to allow air suction. through these slits and through the surface of the water.

3. Apparatus according to claim 11, characterized in that the permeable pressing member comprises a short endless band of metal wires passing around guide rollers and has, with respect to said waterway, so as to form a wedge-shaped entrance between the metal belt and the conveyor belt which moves the layer of pulp on which the downward pressure is applied, in order to press this pulp and separate the water therefrom, from which at least a portion passes upward through the permeable member.

4. Apparatus according to claim 11, characterized in that the waterway comprises a tubular gutter of rectangular cross-section, the current of air acting through this gutter to entrain the water and promote its flow towards the gutter and beyond it.

5. Apparatus according to sub-claim 4, characterized in that said waterway terminates at its upper front part in a box cooperating with a fan producing said current of air, said box communicating with a flow conduit arranged for RTI ID="0005.0273" WI="12" HE="4" LX="1043" LY="1446"> to receive the water leaving said waterway.