DK156246B

DK156246B - EXPRESSION FOR EXTRACTION OF A LIQUID PHASE IN A PULFUL MASS

Info

Publication number: DK156246B
Application number: DK219984A
Authority: DK
Inventors: Robert Duchamp; Roland Plever; Patrick Truchot
Original assignee: Seram Soc Et Rech Arts Metiers
Priority date: 1983-05-04
Filing date: 1984-05-03
Publication date: 1989-07-17
Also published as: DE3460549D1; FR2545416B1; EP0125982A1; SU1227108A3; DK219984D0; FR2545416A1; ATE21651T1; DK219984A; NO159357B; EP0125982B1; NO841767L; NO159357C; DK156246C

Abstract

1. A press for the extraction of a liquid phase contained in matter similar to a pulp, by pressure of thin layers of pulp alternating with turns of a fabric having channels for evacuation of the liquid phase, characterized in that it comprises an envelope (1) which opens along a longitudinal line in order to make a first longitudinal inlet (26) appear, a shaft (10) mounted coaxially with this envelope (1) and passing through it freely, a winding drum (13) having a central hub (14) keyed in rotation onto the shaft (10) inside the envelope (1) and defining with it an annular space (15), an annular chamber (20) having a volume which may be expanded and contracted in the direction radial to the envelope (1) and partially occupying the said annular space (15), the said chamber (20) being connected to a source of fluid under pressure and having a longitudinal slit opening in order to make a second longitudinal inlet (26') appear to correspond with the first inlet (26), and a supporting fabric (27) which is attached by one end to the central hub (14) and may be wound round and unwound with respect to the latter, the envelope (1) being equipped with means of collection (4, 5, 6, 7) of the liquid phase expressed from the pulp.

Description

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Opfindelsen omhandler en presse til ekstraktion af en flydende fase i en pulpagtig masse, af den i krav l's indledning angivne art.The invention relates to a press for extracting a liquid phase in a pulpy mass, of the kind set forth in the preamble of claim 1.

Fra beskrivelsen til fransk patent nr. 2.53Q482 kendes 5 en fremgangsmâde til komprimering af en sâdan pulp, især roepulp, i et antal alternerende tynde lag med en dug med evakueringskanaler for den flydende fase.From the disclosure of French Patent No. 2.53Q482, a method for compressing such a pulp, especially beet pulp, is known in a number of alternating thin layers with a liquid phase evacuation duct.

Opfindelsen har til formai at angive et hensigtsmæssigt apparat til udovelse af denne fremgangsmâde, hvilket 10 apparat er ejendommeligt ved den i krav l's kendetegnen- de del angivne konstruktion.The invention has for its object to provide a suitable apparatus for practicing this method, which apparatus is peculiar to the construction as defined in claim 1.

Opfindelsen forklares nærmere nedenfor i forbindelse med tegningen, hvor: fig. 1 er en delvis gennemskâret afbildning fra siden 15 af en presse ifalge opfindelsen, fig. 2 er en afbildning fra enden af pressen pâ fig.The invention is further explained below in connection with the drawing, in which: FIG. 1 is a side sectional view of a press of the invention; FIG. 2 is an end view of the press of FIG.

1, gennemskâret langs linien II-II, og fig. 3 er et længdesnit gennem pressen pâ fig. 1 og 2, en tragt med to fordelingsâbninger, en genoprulnings- 20 tromle og en bortledningstransportor.1, cut along line II-II, and fig. 3 is a longitudinal section through the press of FIG. 1 and 2, a hopper with two distribution openings, a reel drum and a drain conveyor.

Pressen ifolge opfindelsen omfatter en fortrinsvis cylin-derformet kappe 1 med en sidevæg 2, i hvis yderste mod-stâende partier der er udboret radiale huiler 3 langs omkredsen, hvilke huiler er dækket af to periferiske 25 render henholdsvis 4 og 5 i U-form, hvilke render er anlagt imod yderfladen af sidevæggen 2 til opfangning af al væske, der lober ud gennem de radiale huiler 3, og forer væsken til en tilhorende opsamler 6 og 7, der er forbundet med rendernes nederste punkt.The press according to the invention comprises a preferably cylindrical sheath 1 with a side wall 2, in the outermost opposing portions of which are bored radial cavities 3 along the circumference, which cavities are covered by two peripheral ridges 4 and 5 in U-shape, respectively. which bores are disposed against the outer surface of the side wall 2 for trapping all liquid flowing through the radial cavities 3 and feeding the fluid to an associated collector 6 and 7 connected to the bottom of the bores.

22

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De yderste modstâende vægge 8 og 9 af den cylindriske kappe 1 kan være partielle ud fra sidevæggen 2. I aile tilfælde gâr en koaksialt med kappen 1 monteret aksel 10 igennem sidevæggen 2 og understattes af ydre lejer 5 11 og 12, og i det indre af kappen 1 understatter akselen 10 en til akselen fastkilet oprulningstromle 13. Cylinde-ren 13 omfatter et centrait nav 14 med en mindre diameter end diameteren af sidevæggen 2, sa at navet sammen med denne afgrænser et ringformet mellemrum 15. To yderflanger 10 16 og 17 strækker sig i tværgâende planer ud fra den centrale kerne 14 nær op til sidevæggen 2. Dennes radiale huiler 3 befinder sig fortrinsvis i det væsentlige ud for inderfladen af de to yderflanger 16 og 17, og til hver af disse inderflader er-der fastgjort et ring-15 formet bând henholdsvis 18 og 19 af filterdug som nærmere beskrevet nedenfor.The outermost resilient walls 8 and 9 of the cylindrical sheath 1 may be partial from the side wall 2. In all cases, a coaxial shaft 10 mounted through the sheath 1 passes through the side wall 2 and is supported by outer bearings 5 11 and 12, and in the interior of the The sheath 1 supports the shaft 10 a reel drum 13 which is wedged to the shaft. The cylinder 13 comprises a centrait hub 14 having a smaller diameter than the diameter of the side wall 2, so that the hub together with it defines an annular space 15. Two outer flanges 10 16 and 17 extend in transverse planes projecting from the central core 14 close to the side wall 2. Its radial cavities 3 are preferably substantially adjacent to the inner surface of the two outer flanges 16 and 17, and to each of these inner surfaces a ring is attached. 15 formed ribbon 18 and 19 respectively of filter cloth as described below.

I det ringformede kammer 15 er der anbragt et udvideligt og sammentrækkeligt kammer 20, der er forbundet med en (ikke vist) trykfluidumskilde gennem en kanal 21, 20 der gâr igennem sidevæggen 2. Kammeret 20 er anlagt imod sidevæggens inderflader og opfylder ikke hele det ringformede mellemrum 15.In the annular chamber 15 is provided an expandable and contractible chamber 20, which is connected to a (not shown) pressure fluid source through a channel 21, 20 passing through the side wall 2. The chamber 20 is arranged against the inner wall of the side wall and does not meet the entire annular space 15.

Den cylinderformede kappe 1 kan âbnes, idet den er sammen-sat af to partier IA og IB, der kan monteres indbyrdes 25 langs et diametralt plan (fig. 3). Pâ den ene side er der et hængsel 22 for de to partier IA og IB, og pâ den modsatte side er der askener 23, der alternerer i længderetningen pâ de to partier og hver især har en âbning 24, gennem hvilken man indfarer en dorn 25 30 (fig. 1), nâr hullerne flugter sammen efter lukning af kappen 1.The cylindrical sheath 1 can be opened as it is composed of two portions IA and IB which can be mounted mutually 25 along a diametrical plane (Fig. 3). On one side there is a hinge 22 for the two portions IA and IB, and on the opposite side there are ashes 23 which alternate longitudinally on the two portions and each has an opening 24 through which a mandrel 25 is accessed. 30 (Fig. 1) when the holes align after closing the sheath 1.

Det ene kappeparti IA er stationært, mens det andet parti IB er svingelig omkring hængslet 22. Nâr partietOne casing portion IA is stationary while the other portion IB is pivotal about the hinge 22. When the portion

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IB er i âben stilling ( f" i g. 3), opstâr der en langs-gâende indgang 26. Ogsâ kammeret 20 kan âbnes, idet det har to ender 20A og 20B, der strækker sig i længde-retningen og korresponderer med de tilsvarende oskener 5 23. I âben stilling afgrænser de to kammerender 20AIB is in the open position (f "in g. 3), a longitudinal entrance 26 is formed, and also chamber 20 can be opened, having two ends 20A and 20B extending longitudinally and corresponding to the corresponding oscillators 5 23. In the open position, the two chamber ends 20a define

og 20B en indgang 26', der ligger i forlængelse af indgan-gen 26. Ud for hængselet 22 forlober kammeret 20 ubrudt, og kammeret er fremstillet af eftergiveligt eller elas-tisk materiale.and 20B, an inlet 26 'which extends into the inlet 26. Out of the hinge 22, the chamber 20 extends unbroken and the chamber is made of resilient or elastic material.

10 En stottedug 27 er ved sin ene ende fastgjort til overfla- den af det centrale nav 14 af oprulningscylinderen 13.10 A web 27 is attached at one end to the surface of the central hub 14 of the reel cylinder 13.

Bredden af dugen 27 er lidt mindre end afstanden imellem de til flangerne 16 og 17 fastgjorte filterduge 18 og 19, sa at dugen 27 kan oprulles pâ sig selv omkring 15 det centrale nav 14 imellem filterdugene 18 og 19.The width of the tablecloth 27 is slightly less than the distance between the filter tabs 18 and 19 attached to the flanges 16 and 17, so that the tablecloth 27 can be wound on itself about 15 the central hub 14 between the filter tabs 18 and 19.

Nâr den cylinderformede kappe 1 og kammeret 20 befinder sig i âben stilling, passererer stettedugen 27 igennem indgangene 26 og 26' og strækker sig hen til genoprul-ningstromlen 29 beliggende uden for kappen 1. Hensigts-20 mæssigt passerer stettedugen 27 under en udlebsâbning 30 fra en tragt 31 med en bundtransporter 32, hvis bredde, ligesom bredden af âbningen 30, svarer til bredden af dugen 27. Tragten 31 indeholder pulp 33, som bundtrans-porteren 32 udgyder med en reguleret gennemstremning pâ 25 stettedugen 27.When the cylindrical sheath 1 and chamber 20 are in the open position, the blanket 27 passes through the inlets 26 and 26 'and extends to the reel drum 29 located outside of the sheath 1. Conveniently, the blanket 27 passes under an outlet opening 30 from a hopper 31 having a bottom conveyor 32, the width of which, like the width of the opening 30, corresponds to the width of the tablecloth 27. The hopper 31 contains pulp 33 which the bottom conveyor 32 emits with a regulated throughput of the cleaning cloth 27.

Det er yderligere fordelagtigt at udforme tragten 31 symmetrisk ved at tilvejebringe en âbning 30' symmetrisk i forhold til et centrait plan og at anvende en reversibel bundtransporter 32. Efter passagen under âbningen 30 30 passerer stettedugen 27 omkring en omlebsvalse 34, fer den nâr hen til genoprulningstromlen 29, der ligger nærmere ved den cylinderformede kappe 1. Herved kan man symmetrisk installere en anden omlebsvalse 34', 4It is further advantageous to design the funnel 31 symmetrically by providing an aperture 30 'symmetrical to a centrait plane and using a reversible bottom conveyor 32. After the passage under the aperture 30 30, the blanket 27 passes around an annular roll 34, it approaches the rewind drum 29, which is closer to the cylindrical sheath 1. Hereby another rotary roller 34 ', 4 can be symmetrically installed

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omkring hvilken en anden stattedug 27' lober rundt imel-lem en anden cylinderfortnet kappe og en anden genoprul-ningstromle (ikke vist), hvor stottedugen 27' passerer under âbningen 30' i tragten 31. Omlabsvalserne 34 og 5 34' forlaber parallelt, hvilket ogsâ gælder genoprul- ningsvalserne 29, sa at der er monteret en enkelt bort-ledningstransportar 35 nedenunder med et yderparti be-liggende under de to omlobsvalser 34 og 34'. Disse sidste kan eventuelt undværes ved samme sted kun at montere 10 selve genoprulningstromlerne 29 tæt ved hinanden.around which another anvil 27 'runs around between another cylindrical sheath and another reel drum (not shown), where the anvil 27' passes under the aperture 30 'of the funnel 31. The circumferential rollers 34 and 5 34' leave parallel, which the rewind rollers 29 also apply so that a single discharge conduit 35 is mounted underneath with an outer portion located under the two orifice rollers 34 and 34 '. These latter can optionally be avoided at the same location only to mount the rewinding drums 29 themselves close together.

Hver at stattedugene 27 og 27' er fastgjort til den tilharende genoprulningstromle 29 ved hjælp af to langs-gâende trækkabler for enden af dugen. Nâr dugen 27 er helt oprullet omkring det centrale nav 14, passerer 15 trækkablerne igennem hvert sit tilsvarende indhak 36 (fig. 1) ved kanten af det ene af patierne IB, der afgræn-ser indgangen 26. Man kan da helt lukke den cylinderforme-de kappe 1 indeholdende hele den oprullede stattedug 27, uden at denne opharer med via kablerne at være for-20 bundet med den tilsvarende genoprulningstromle 29. Du gen 27 kan hensigtsmæssigt fastgares til det centrale nav 14 ved hjælp af trækkabler til at kunne udnytte hele dugens længde.Each of the tablecloths 27 and 27 'is attached to the associated reel drum 29 by means of two longitudinal pull cables at the end of the tablecloth. When the tab 27 is fully wound around the central hub 14, the tow cables pass through each of their corresponding notches 36 (Fig. 1) at the edge of one of the paths 1B defining the inlet 26. The cylinder molding can then be completely closed. the sheath 1 containing all of the rolled-up cloth 27, without ceasing to be connected via the cables to the corresponding reel drum 29. You gene 27 may conveniently be fastened to the central hub 14 by means of pull cables to be able to utilize the entire cloth. length.

Pressen ifalge opfindelsen fungerer pâ falgende mâde: 25 Tragten 31 er opfyldt med pulpen 33, der skal afvandes, kammeret 20 er sammentrukket, den cylinderformede kappe 1 befinder sig i âben stilling og stattedugen 27 er oprullet omkring genoprulningstromlen 29. Dugen 27 oprul-les omkring det centrale nav 14 belagt med et regulært 30 lag 37 af pulpen 33, doseret af bundtransportaren 32 som vist pâ fig. 3. Nâr stattedugen 27 er blevet helt oprullet pâ det centrale nav 14 i vindinger, hvorimellem der ligger et regelmæssigt og kontinuert pulplag 37,The press according to the invention operates in the following manner: The hopper 31 is filled with the pulp 33 to be dewatered, the chamber 20 is contracted, the cylindrical sheath 1 is in the open position and the statue cloth 27 is wound around the rewind drum 29. The cloth 27 is wound about the central hub 14 coated with a regular layer 30 of the pulp 33 dosed by the bottom conveyor 32 as shown in FIG. 3. When the blanket 27 has been fully wound on the central hub 14 in turns, between which is a regular and continuous pulse layer 37,

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lukkes den cylinderformede kappe 1, idet trækkablerne forlaber gennem indhakkene 36. Derefter komprimeres pulplaget 37 imellem vindingerne af stattedugen 27 ved udtværing af den oprullede enhed omkring det centrale 5 nav 14 ved oppustning af kammeret 20, fortrinsvis ved hjælp af en væske, som vist pâ fig. 2.the cylindrical sheath 1 is closed, the pulling cables leaving through the notches 36. Thereafter, the pulp layer 37 is compressed between the windings of the stud cloth 27 by smearing the rolled-up unit around the central 5 hub 14 by inflating the chamber 20, preferably by means of a liquid as shown on FIG. 2nd

Den fra pulpen 37 udmasede flydende fase falger dugen 27 i dennes tværretning og ankommer til filterdugene 18 og 19, som dækker flangerne 16 og 17, og nâr frem 10 til renderne 4 og 3 til opsamling i opsamlerne 6 og 7. Filterdugene 18 og 19 letter den flydende fases stram-ning imod renderne 4 og 5, men kan erstattes med ækviva-lente midler, eksempelvis render graveret radiait i flangerne 16 og 17 eller bare ved et mellemrum imellem 15 dugens kanter og flangerne, sâfremt der kan opnâs en tilstrækkelig najagtig oprulning til at opretholde et sâdant mellemrum.The liquid phase emitted from the pulp 37 drops the web 27 in its transverse direction and arrives at the filter cloths 18 and 19, which cover the flanges 16 and 17, and reach 10 for the grooves 4 and 3 for collection in the collectors 6 and 7. The filter cloths 18 and 19 facilitate the tightening of the liquid phase against the grooves 4 and 5, but can be replaced by equivalent means, for example, rendered engraved radiait in the flanges 16 and 17 or just at a space between the edges of the tab and the flanges, if sufficient accurate winding can be obtained. to maintain such a gap.

Nâr den opviklede stattedug komprimeres, formindskes dens diameter med en tendens til at danne periferiske 20 svingninger, der er skadelige for en regulær kompression i pulpen. Denne ulempe kan nedbringes ved at tilvejebringe et bestemt forhold imellem diameteren af det centrale nav 14 og diameteren af den pâ navet oprullede dug 27.As the wound cloth is compressed, its diameter decreases with a tendency to form peripheral oscillations which are detrimental to regular compression in the pulp. This disadvantage can be mitigated by providing a definite relationship between the diameter of the central hub 14 and the diameter of the web 27 wound on the hub.

I praksis vil den sidstnævnte diameter være hajst 1,5 25 gange diameteren af det centrale nav 14. Kammeret 20 vælges som falge heraf sêledes, at det i sammentrukket stand frigar omkring det centrale nav 14 det nadvendige mellemrum til oprulning af stattedugen 27.In practice, the latter diameter will be at least 1.5 times the diameter of the central hub 14. The chamber 20 is selected as a drop thereof, so that in the condensed state around the central hub 14 the necessary clearance for winding the web cloth 27 is released.

Nâr presseoperationen er afsluttet, âbnes den cylinder-30 formede kappe 1, og stattedugen 27 oprulles pâ genoprul-ningstromlen 29. En rakel 38 anlægges imod dugen 27 under dens passage omkring omlabsvalsen 34 til at lade den komprimerede pulp falde ned pâ bortledningstranspor- 6When the press operation is completed, the cylindrical sheath 1 is opened and the blanket 27 is wound on the reel drum 29. A blade 38 is applied to the web 27 during its passage around the orifice roll 34 to allow the compressed pulp to fall onto the lead conveyor 6

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t0ren 35. Fig. 3 viser ogsâ udavelsen af derme operation pâ stattedugen 27' ved hjælp af en rakel 38', idet oprul-nings- og afrulningsoperationerne sker samtidigt pâ begge sider af tragten 33 i et symmetrisk anlæg sont beskrevet ovenfor.tower 35. FIG. 3 also shows the execution of this operation on the statue cloth 27 'by means of a blade 38', the rewinding and unrolling operations being carried out simultaneously on both sides of the hopper 33 in a symmetrical system described above.

5 I eih udffarelsesform for anlægget ifalge opfindelsen er hver af dugene 27 og 27' vævet af polyethylenfibre og har en bredde 1 m og en længde pâ 100 m. Den cylin- derformede kappe 1 har en inderdiameter pâ 1,20 m og det centrale nav en diameter pâ 0,70 m. Den lineære 10 hastighed af stattedugene 27 og 21' kan reguleres imellem 0,3 og 1 m/s. Mængden af den aflejrede pulp kan indregu- 2 leres til 14 kg/m . Det totale energiforbrug er 0,5 kWh pr. ton pulp, hvilket svarer til en besparelse pâ 17,5 kg af masut pr. ton pulp, sammenlignet med en kon-15 ventionel tarring ved opvarmning.In one embodiment of the plant according to the invention, each of the tabs 27 and 27 'is woven of polyethylene fibers and has a width of 1 m and a length of 100 m. The cylindrical sheath 1 has an inner diameter of 1.20 m and the central hub. a linear diameter of 0.70 m. The linear velocity of the statues 27 and 21 'can be adjusted between 0.3 and 1 m / s. The amount of pulp deposited can be adjusted to 14 kg / m 2. The total energy consumption is 0.5 kWh per hour. per tonne of pulp, which is equivalent to a saving of 17.5 kg of fuel per tonne. tons of pulp, compared to a conventional tarring on heating.

Kammeret 20 er fremstillet af en varmesvejst polyurethan med en tykkelse pâ 1 mm og har en forlængelse pâ 400 %. Komprimeringen af dugen 27 og pulpen 37 imod det centrale nav 14 sker ved et tryk pâ 50 bar under 10 min.The chamber 20 is made of a heat welded polyurethane with a thickness of 1 mm and has an elongation of 400%. The compression of the tab 27 and the pulp 37 against the central hub 14 takes place at a pressure of 50 bar for less than 10 minutes.

20 I en forenklet udfarelsesforra for apparatet ifalge opfin delsen har oprulningscylinderen 13 ingen flanger 16 og 17 og ingen filterduge 18 og 19, men kun det centrale nav 14, pâ hvilken stattedugen 27 oprulles. I denne udfa-udfarelsesform kan man ogsâ undvære renderne 4 og 5, 25 men den cylinderformede kappe 1 bar fortrinsvis forsynes med komplette ydervægge 8 og 9, der helt indelukker oprulningscylinderen 13 under komprimeringen.In a simplified embodiment of the apparatus according to the invention, the reel cylinder 13 has no flanges 16 and 17 and no filter cloths 18 and 19, but only the central hub 14 on which the blanket 27 is wound. In this embodiment, the grooves 4 and 5, 25 can also be dispensed with, but the cylindrical sheath 1 is preferably provided with complete outer walls 8 and 9 which completely enclose the reel cylinder 13 during compaction.

Claims

7 DK 156246 B Patent claims:

A press for extracting a liquid phase into a pulpy mass by compressing thin pulp layers alternating with turns of a tablecloth with evacuation channels for the liquid phase, characterized in that it comprises a sheath (1) openable along a longitudinal union for forming a longitudinal entrance (26), a shaft (10) coaxially and freely mounted with a shaft (1), a reel cylinder (13) 10 with a keyed hub (14) fixed to the shaft (10) the interior of the casing (1) and, together with this, delimited an annular space (15), an annular chamber (20) having a radially expandable and controllable volume which partially fills the annular space ( 15), which chamber (20) is connected to a pressurized fluid source and has a longitudinal aperture slot to form a longitudinal entrance (26 ') corresponding to the entrance (26') and a support cloth (27) which is at one end attached to the central hub (14) and which can be wound up and a is folded in relation thereto, wherein the sheath (1) is provided with collecting means (4, 5, 6, 7) for the pulp extruded from the liquid phase.

Press according to claim 1, characterized in that the plunger cloth (27) is provided with at least one pulling cable at the end opposite to the end fixed to the winding cylinder (13) and that the openable sheath (1) the edges around the entrance (26) provide at least one notch (36) for passage of the pull cable 30 under the closed state of the sheath (1) »

Press according to claim 1, characterized in that the winding cylinder (13) at the opposite ends of the central hub (14) has radial flanges (16, 17), the inner surfaces of each of which present means adapted for radial tension. direction.

Press according to claim 3, characterized in that the means for promoting the tensioning are formed as filter cloths (18, 19), which are attached to the inner surfaces of the flanges (8, 9).

Press according to claim 1, characterized in that the filter cloth (27) is attached to the reel cylinder (13) by at least one pulling cable.

Press according to claim 1, characterized in that the end of the stud cloth (27) which faces opposite the end fixed to the reel cylinder (13) is fixed to a reel drum (29).

Press according to Claim 6, characterized in that the statewide cloth (27) between the rewind drum (29) and the open sheath (1) is operated under a hopper (31) with a bottom conveyor (32) and with at least one of the bottom conveyor (32). ) provided outlet opening (30) for laying the pulp of the statewide cloth (27) during its winding on the central hub (14) and its winding from the rewinding drum (29).

Press according to claim 6, characterized in that a deflection conveyor (35) is arranged below the rewind drum (29) for accommodating the pulp compressed during the rewind of the state cloth (27) on which the pulp (38) abuts the tablecloth (27).

Press according to claim 7, characterized in that the hopper (31) has two outlet openings (30, 30 ') which are symmetrical with respect to a centrait plane, that the bottom conveyor (32) is reversibly formed, and that two open caps (1) and two reel rollers (29) are arranged symmetrically with respect to said central plane with a cloth (27, 27 ') disposed below each opening (30, 30'), each of which the whole is situated above a common diversion conveyor (35).

Press according to Claim 1, characterized in that the retracting means for the extruded liquid phase comprise radial howls (3) through the side wall (2) of the sheath (1) as well as peripherally extending grooves (4, 5) covering the holes (3). and is associated with collectors (6, 7).