Press apparatus with a pressing roller

Abstract

The invention relates to a device (1) for producing a web from a fiber-containing material, in particular tissue paper, comprising at least one continuous belt (2) for supporting and transporting a fibrous web (3). Additionally, at least one press roller (5) is provided, having: a longitudinal central axis (6), a lateral surface (9), a radial direction (10) which is arranged in the direction of the longitudinal central axis (6) starting from the lateral surface (9), and a rotational direction (11), with respect to which the press roller (5) is rotatably mounted. A gap (12) is formed between the press roller (5) and the continuous belt (2) in order to press the fibrous web (3), and a press substrate (13) is provided which is guided about at least one sub-region (14) of the lateral surface (9) of the press roller (5) so as to contact same, wherein the press roller (5) comprises multiple recesses (15) on the lateral surface (9), said recesses (15) being guided to at least one cavity (16) and opening into the at least one cavity, and the cavity (16) is arranged within the press roller (5) with respect to the radial direction (10). A negative pressure-generating unit (17) is provided, by means of which a negative pressure can be produced in the at least one cavity (16).

Description

[0001] The invention relates to a device for producing a web from a fibrous material, in particular tissue paper.

[0002] The device comprises at least one endless belt for supporting and transporting a fiber web with respect to a transport direction, which transport direction is defined by a rotation direction of the endless belt.

[0003] Furthermore, at least one pressure roller is provided, comprising: a longitudinal central axis, a cylindrical surface extending between a first end face and a second end face; a radial direction, which radial direction is arranged in the direction starting from the cylindrical surface towards the longitudinal central axis, and a direction of rotation, with respect to which direction of rotation the pressure roller is rotatably mounted; wherein a gap is formed between the at least one pressure roller and the at least one endless belt for pressing the fiber web.

[0004] It should be noted at the outset that a "direction of rotation" generally refers to a direction of rotation corresponding to the transport direction, which arises when the pressure roller is pressed against the endless belt due to the belt's movement or rotation. The pressure roller may also have an additional drive that imparts a specific rotational speed to it in this direction. For ease of understanding, the direction of rotation can also be considered the circumferential direction of the roller.

[0005] The device also includes at least one pressing substrate, in particular a pressing felt, for dewatering the fiber web, which pressing substrate is guided in contact with at least a partial area of ​​the outer surface of the pressure roller.

[0006] Tissue paper is frequently used for paper hygiene products such as toilet paper, paper handkerchiefs, paper napkins, paper cleaning cloths, etc., due to its absorbency.

[0007] A device for drying and treating a moving fiber web in a machine intended for the production of tissue paper is known from US 8486229 B2, wherein the device comprises a continuously circulating metal belt and at least one pressure roller located outside the metal belt, which pressure roller is in contact with the metal belt, whereby a fiber web can adhere to the metal belt by means of the contact; and a humidifier by means of which the fiber web can be treated before being transferred to the metal belt. Furthermore, a fabric is provided by which the fiber web is supported in a press gap between the pressure roller and the metal belt before being transferred.

[0008] In DE29822227 U1, a suction roller arrangement for a press of a pulp machine is disclosed, which has a suction roller with a first and a second suction chamber, and includes two counter-pressure rollers below the suction roller, wherein the pulp web can be held on the surface of the roller in the area of ​​a first roller gap by means of the first suction chamber and can be dewatered in the area of ​​a second roller gap.

[0009] DE19728823 A1 also discloses a suction roller for a paper machine, comprising a roller shell over which a conveyor belt for a fiber web to be dewatered is guided and which has an external suction box that partially encloses the suction roller from the outside and applies negative pressure to the fiber web via recesses in the roller shell, wherein the suction box is sealed by sealing elements transverse to the web direction.

[0010] Further devices for producing a fiber web, which include suction rollers, are disclosed in EP3623525 A1 and WO2013009256 A1.

[0011] CN205188702 U discloses a suction roller with a roller shell and a vacuum chamber arranged within the roller shell, which has several suction holes. The vacuum chamber is arranged along the axial direction of the suction roller, and several through-holes are formed in the circumferential direction in the shell of the suction roller.

[0012] A disadvantage of prior art designs is that centrifugal forces can often lead to renewed, uneven moistening or irrigation of the fiber web in the area after the press gap.

[0013] The object of the present invention was to overcome the disadvantages of the prior art and to provide a device by means of which a user is able to optimize the pressing process and prevent unwanted watering. This object is achieved by a device and a method according to the claims.

[0014] The device according to the invention comprises a pressure roller, wherein the pressure roller has several recesses on its outer surface, which recesses lead to at least one cavity and open into which at least one cavity is arranged within the pressure roller with respect to the radial direction, and wherein a vacuum generation unit is provided, by means of which vacuum generation unit a vacuum can be produced in the at least one cavity.

[0015] This largely prevents unwanted watering of the fiber web.

[0016] In a further development, the recesses can be configured as channels, which are inclined at an angle to the radial direction, and in which a channel inlet is positioned upstream of a channel outlet with respect to the direction of rotation. The channel inlet is located on the lateral surface, and the channel outlet opens into the at least one cavity. This configuration offers the advantage of facilitating the flow of liquid towards the cavity, as the inclination of the channels forces the liquid inwards during rotation. The angle can be between 1° and 45°, preferably between 5° and 30°, and particularly between 5° and 20° to the radial direction.

[0017] For the sake of completeness, it should be mentioned that the recesses can, in principle, be designed as channels in all versions, regardless of their inclination and arrangement.

[0018] It can be particularly advantageous if the recesses have a rectangular cross-section perpendicular to the radial direction. This offers the benefit of providing the largest possible suction area, especially in or immediately after the press gap, when the fiber web leaves the press substrate.

[0019] Furthermore, the recesses can be designed to have stepped depressions in the radial direction, with the depth of the depressions decreasing radially from the outer surface towards the longitudinal center axis. An advantage of this is that fluid can be additionally retained in the depressions against centrifugal forces, preventing it from escaping in the opposite direction.

[0020] Furthermore, one embodiment allows the cavity to be cylindrical and concentric with respect to the longitudinal center axis, extending at least partially between the first and second end faces. This embodiment offers the advantage that additional structural elements can be arranged within the pressure roller, or that the vacuum generation unit can also be integrated into the pressure roller. These elements can be rotatable with the pressure roller or rigidly mounted. This embodiment also allows the pressure roller to be mounted on a shaft, a journal, or similar component.

[0021] For the sake of completeness, it should be mentioned that the cavity is sealed at least in the areas of the end faces or between them, as otherwise it would be impossible to create a vacuum in the cavity if it extends to an end face. Furthermore, at least one suction channel can be arranged in the cavity, which is parallel to the longitudinal center axis and connected to the vacuum generation unit. This design offers the advantage that the suction effect of the vacuum generation unit can be directed precisely to a specific area. In addition, it prevents the pressure roller from being contaminated by the liquid inside its interior.

[0022] According to the invention, a shaft is arranged in the cavity by means of which the pressure roller is rotatably mounted and in which at least one vacuum line is formed, which vacuum line is connected to the vacuum generation unit. This offers the advantage that the pressure roller can be mounted stably and that no further elements are required to create the vacuum in the cavity. The shaft can, for example, have bearing rings with seals, so that a seal of the cavity is ensured.

[0023] It can be advantageous if the shaft has at least one groove parallel to the longitudinal center axis, by means of which the vacuum line is in operative contact with the recesses in certain areas. The advantage here is that the suction effect can again be directed specifically to a certain area, thus ensuring optimal fluid removal in that area. In this design, the vacuum line can be formed by the groove itself.

[0024] For the sake of completeness, it should be mentioned that "area in active connection" refers to an area of ​​the cavity and the recesses that is essentially located between the groove and the outer surface.

[0025] It is particularly advantageous if the groove is positioned within a section of the gap, relative to the direction of rotation. This allows the suction effect to be directed precisely into the area of ​​the press gap or even just beyond it, ensuring optimal fluid drainage in this area.

[0026] It should also be noted that a press gap can be of varying lengths, so that, for example, in the case of an endless belt which may be guided over several rollers and arrangements, it is arranged over a larger area of ​​the outer surface of the pressure roller.

[0027] In one embodiment, at least one cover may be arranged in the cavity, which cover is designed to seal several recesses in certain areas. This embodiment offers the advantage of sealing recesses in areas with respect to the direction of rotation that should not be subjected to negative pressure, thus preventing unnecessary suction loss.

[0028] In a further development, it may be provided that the pressure roller has several cavities. For example, several cavities parallel to the longitudinal center axis can be arranged along the circumference of the pressure roller and connected to the vacuum generation unit, thus enabling the targeted direction of the vacuum to specific recesses. The pressure roller may also have a cylindrical, concentric cavity along the longitudinal center axis, or it may have no cavity in this area.

[0029] Furthermore, the multiple cavities can be arranged at a constant radius to the longitudinal center axis. This design offers the advantage that the cavities can be more easily connected to the vacuum generation unit, e.g., via a common annular channel or the like.

[0030] Furthermore, the outer surface of the pressure roller can be heated. Additional heating of the pressing substrate can further prevent liquid from escaping in the radial direction.

[0031] It can be advantageous to install a drainage filter upstream of the vacuum generation unit, allowing collected liquid to be returned to a system circuit. This measure contributes to improved energy efficiency and cost-effectiveness of the device.

[0032] An inventive device is not limited to the products mentioned above; for example, it is also suitable for processing nanocellulose or cellulose nanofibrils CNF or CMF.

[0033] To better understand the invention, it is explained in more detail with reference to the following figures.

[0034] They each show, in a highly simplified, schematic representation: Fig. 1 a device for the production of tissue paper; Fig. 2 a design of a printing roller according to the invention in oblique view; Fig. 3 an embodiment of a printing roller in sectional view; Fig. 4 a section of a printing roller in sectional view; Fig. 5 an embodiment of a printing roller in oblique view; Fig. 6 an embodiment of a printing roller in sectional view; Fig. 7 an embodiment of a printing roller in sectional view.

[0035] It should be noted at the outset that in the differently described embodiments, identical parts are provided with the same reference numerals or component designations, and the disclosures contained in the entire description can be applied analogously to identical parts with the same reference numerals or component designations. Furthermore, the positional designations chosen in the description, such as top, bottom, side, etc., refer to the figure directly described and illustrated, and these positional designations must be applied analogously to the new position if the position changes.

[0036] In Fig. 1 A device 1 for the production of tissue paper is shown, which has an endless belt 2 for supporting and transporting a fiber web 3. A direction of rotation or transport 4 of the endless belt 2 is shown in Fig. 1indicated by an arrow. Furthermore, the device 1 comprises a pressure roller 5, which has a direction of rotation 11 corresponding to the transport direction 4, with respect to which direction of rotation 11 the pressure roller 5 is rotatably mounted, and which direction of rotation 11 is also a circumferential direction of the pressure roller 5. The direction of rotation of the endless belt 2 is clockwise in the form shown, which results in a counterclockwise direction of rotation 11 of the roller. It should be noted that with a different spatial arrangement of the endless belt and the resulting transport direction, the direction of rotation is also configured accordingly.

[0037] A gap 12 is formed between the pressure roller 5 and the endless belt 2 for pressing the fiber web 3. The endless belt 2 is supported, for example, by several rollers, at least one of which can be driven to drive the endless belt 2. Even if in Fig. 1While three rollers are shown, the number of rollers around which the endless belt 2 rotates can vary between two and any number of rollers, depending on the embodiment. As mentioned at the beginning, the pressure roller 5 can also be driven.

[0038] The fiber web 3 is transported into the gap 12, where it is pressed by the pressure roller 5 and the continuous belt 2. Transport of the fiber web 3 to the gap 12 can be accomplished by means of an additional conveying device, for example, a mat made of wire, a textile material, etc. (not shown here), in a manner known per se. Preferably, a pressing substrate 13, in particular a pressing felt, is provided, which is guided in contact with the pressing substrate 13 around at least a partial area 14 of a surface 9 of the pressure roller 5. The continuous belt 2 transports the fiber web 3 from the gap 12 in the transport direction 4 of the continuous belt 2. The continuous belt 2 and the fiber web 3 on it can be heated by means of heating elements (not explicitly shown here), for example, hot air blowers, in order to dry the fiber web 3. The rollers can also be heated.After the fiber web 3 has dried, it can be peeled off the continuous belt using a peeling device. The fiber web can also be creped using the peeling device, for example a scraper, in particular a crepe scraper, or a roller.

[0039] In Fig. 2 Figure 1 shows an embodiment of a pressure roller 5 according to the invention in an oblique view. The pressure roller 5 has a longitudinal central axis 6 and a cylindrical surface 9 extending between a first end face 7 and a second end face 8. Furthermore, the pressure roller 5 comprises a radial direction 10, which is arranged in the direction extending from the cylindrical surface 9 towards the longitudinal central axis 6, and a direction of rotation 11, with respect to which direction of rotation 11 the pressure roller 5 is rotatably mounted.

[0040] According to the invention, the pressure roller 5 has several recesses 15 on its outer surface 9, which recesses 15 lead to at least one cavity 16 and open into the at least one cavity 16, which cavity 16 is arranged within the pressure roller 5 with respect to the radial direction 10.

[0041] Furthermore, a vacuum generation unit 17 is provided, by means of which a vacuum can be created in the cavity 16. The vacuum generation unit 17 can be arranged outside the pressure roller 5 as shown, but also inside it, e.g. in the cavity 16.

[0042] The cavity 16 can have different shapes, e.g. cuboid, prism-shaped, or cylindrical, as shown.

[0043] Regardless of the design of the pressure roller, the vacuum generation unit 17 can be formed by a device known from the prior art, e.g. a rotary lobe pump or vacuum pump, or other devices with which a vacuum can be produced.

[0044] In Fig. 3 An embodiment of a pressure roller 5 is shown in sectional view, in which the recesses 15 are designed as channels, which channels are inclined at an angle 18 with respect to the radial direction 10, and in which a channel inlet 32 ​​is positioned upstream of a channel outlet 33 with respect to the direction of rotation 11, wherein the channel inlet 32 ​​is arranged on the outer surface 9 and the channel outlet 33 opens into the at least one cavity 16.

[0045] Also shown is a press substrate 13 as well as a fiber web 3 and a section of an endless belt 2.

[0046] The vacuum generation unit 17 can be located inside the pressure roller 5, or outside of it.

[0047] Regardless of the design of the pressure roller 5 and the recesses 15, the outer surface 9 can be designed to be heated, such that heating elements 26 are arranged inside the pressure roller 5, as indicated by the dashed lines. The heating elements 26 can be, for example, resistive, i.e., designed as resistance heating. Alternatively, it would also be conceivable to design the heating elements to be inductively heated.

[0048] Furthermore, as in Fig. 3 As indicated, regardless of the design of the recesses 15, at least one cover 29 is provided, which cover 29 is designed to seal several recesses 15 in certain areas. This design serves to seal recesses 15 which, as mentioned at the outset, are not to be subjected to negative pressure.

[0049] Preferably, the cover 29 is rigidly arranged and non-rotatable with the pressure roller 5. At its edges, the cover 29 may preferably have seals (not shown) with sliding properties, or the cover 29 itself may be made of a sliding material. For example, the cover may extend over the entire cavity 16 with respect to the longitudinal center axis 6. Furthermore, several covers 29 may be provided with respect to the direction of rotation and / or in the direction of the longitudinal center axis 6. The at least one cover 29 may also cover a large part of an inner surface 30 of the pressure roller 5, such that, for example, all recesses 15 except those in the area of ​​the gap 12 are covered, for example, more than 60%, in particular 75–90%, of the recesses 15.

[0050] In Fig. 4Figure 1 shows a section of a pressure roller 5 in sectional view, in which the recesses 15 have stepped depressions 19 in the radial direction 10. The depth 20 of the depressions 19 decreases in the radial direction 10, starting from the outer surface 9 in the direction of the longitudinal center axis 6.

[0051] This design offers the advantage that the recesses 19 provide additional retention of liquid within the indentations, as indicated, thus better preventing its re-emergence due to centrifugal forces. The recesses 19 can also have additional pockets opposite the radial direction 10, as indicated by the dashed lines.

[0052] In Fig. 5Figure 1 shows an embodiment of a pressure roller 5 in oblique section, in which the cavity 16 is cylindrical and concentric with respect to the longitudinal center axis 6 and extends at least partially between the first and second end faces 7, 8. The front region of the pressure roller 5 with the first end face 7 is indicated by dashed lines.

[0053] According to the invention, a shaft 22 is arranged in the cavity 16, on which shaft 22 the pressure roller can be rotatably mounted, and in which shaft 22 at least one vacuum line 23 is formed, which is connected to the vacuum generating unit 17. For this purpose, the shaft 22 can, for example, be designed as a hollow shaft. Furthermore, in an embodiment not shown, the vacuum line 23 can have individual lines extending towards the outer surface of the shaft 22.

[0054] The shaft 22 can, as shown, have at least one groove 24 parallel to the longitudinal center axis 6, by means of which groove 24 the vacuum line 23 is in operative connection with the recesses 15 in the cavity 16 in certain areas, and which groove 24 is preferably arranged in a region of the gap 12 with respect to the direction of rotation 11 or circumferential direction. A vacuum line 23' can also be formed through the groove 24 itself, as indicated.

[0055] The pressing substrate and the fiber web are not shown for the sake of simplicity.

[0056] This design has the advantage that the suction effect of the vacuum generation unit 17 in the cavity 16 can be directed specifically into the area required for this purpose, namely in the area of ​​the press gap, as mentioned at the beginning.

[0057] The size of the groove 24 can be chosen differently, especially depending on the length and width of the slot 12.

[0058] The pressure roller can be supported, for example, by shoulders or ring webs on the shaft 22. Bearing rings 28 can be provided for this purpose, as indicated by the dashed lines. Preferably, the bearings are provided with a seal to prevent suction loss.

[0059] Regardless of the embodiment of the pressure roller 5 or the cavity 16, the recesses 15 on the outer surface 9 can have a rectangular cross-section perpendicular to the radial direction 10, as shown. A rectangular cross-section promotes the drainage of liquid, since the largest possible suction area is ensured in the region of the contact surface between a pressing substrate and the pressure roller.

[0060] In Fig. 6Figure 1 shows a cross-sectional view of an embodiment of a pressure roller 5, in which a suction channel 21 is arranged in the cavity 16. This suction channel 21 is parallel to the longitudinal center axis 6 and is connected to the vacuum generation unit 17. Multiple suction channels can also be arranged, as indicated by the dashed lines.

[0061] The suction channels can, for example, be designed as strips with arranged nozzles. This design, in turn, serves to direct the suction effect specifically into the area of ​​a press gap. For this purpose, additional seals can be arranged at the end of the suction channel 21 that is inclined towards the outer surface 9; these seals are designed to slide on the inner surface 30 of the pressure roller 5.

[0062] A combination of a shaft with a groove according to Fig. 5 and a suction channel arranged in the groove would also be conceivable, which would contribute to stabilizing the suction channel.

[0063] Regardless of the embodiment of the pressure roller 5, a drainage filter 25 can be provided upstream of the vacuum generation unit 17, by means of which a collected liquid can be returned to a system circuit. A corresponding line from the vacuum generation unit 17 to the suction channel 21 or to the drainage filter 25 is indicated by dashed lines.

[0064] In Fig. 7Figure 1 shows a sectional view of an embodiment of a pressure roller 5, in which the pressure roller 5 has several cavities 16. These cavities 16 are channel-like and extend along or parallel to the longitudinal center axis 6. Recesses 15 lying on a plane 27, which plane 27 is parallel to the longitudinal center axis 6 and parallel or inclined to the radial direction 10, can, for example, all lead to a common cavity 16. Furthermore, several recesses 15 from different planes 27 can also lead to a common cavity 16', as indicated by dashed lines. The recesses 15 can also be designed as channels inclined at an angle to the radial direction 10, as shown in Figure 1. Fig. 3 .

[0065] The cavities 16 can be connected, for example, to the vacuum generation unit 17 via an annular channel 34, which is indicated section by section. With respect to the longitudinal center axis 6, the cavities 16 can also be interrupted, so that several cavities 16 are arranged one behind the other in the direction of the longitudinal center axis 6. Thus, the cavities 16 can be arranged at a constant radius 31 to the longitudinal center axis 6, but also, for example, offset at different radii 31, as indicated by dashed lines. Preferably, the cavities 16 are formed parallel to the longitudinal center axis 6. The vacuum generation unit 17 can, in turn, be arranged inside or outside the pressure roller 5.

[0066] It may also be provided that the cavities 16. on an end face of the pressure roller 5 are connected to the vacuum generation unit 17 via a shaft seal, or other seals for rotating components known from the prior art.

[0067] The cavities can have a rectangular shape, as shown, but also other geometric shapes, e.g. cylindrical with respect to an axis parallel to the longitudinal center axis 6 or prismatic.

[0068] It can be provided that only those cavities 16 located in a certain area or downstream of the gap are subjected to a negative pressure. For example, a cover can be arranged in a ring channel.

[0069] The pressure roller 5 can be designed as a hollow shaft, as shown, but also as a solid shaft.

[0070] In the Figures 3 to 7 Further and possibly independent embodiments of the pressure roller are shown, whereby the same reference numerals or component designations are used for identical parts as in the preceding illustrations. Figures 1 and 2to be used. To avoid unnecessary repetition, reference is made to the detailed description in the preceding figures.

[0071] The scope of protection is determined by the claims.

[0072] All references to value ranges in this description are to be understood as encompassing any and all sub-ranges thereof, e.g., the reference 1 to 10 is to be understood as including all sub-ranges, starting from the lower limit 1 and the upper limit 10, i.e., all sub-ranges begin with a lower limit of 1 or greater and end with an upper limit of 10 or less, e.g., 1 to 1.7, or 3.2 to 8.1, or 5.5 to 10.

[0073] Finally, for the sake of clarity, it should be noted that, for a better understanding of the structure, some elements have been shown not to scale and / or enlarged and / or reduced in size. Reference numeral list

[0074] 1 device 30 Inner surface 31 radius 2 Endless tape 32 Channel inlet 3 Fiber web 33 Channel outlet 4 Direction of transport 34 Ring canal 5 pressure roller 6 Longitudinal center axis 7 first front 8 second forehead 9 Surface area 10 radial direction 11 Direction of rotation 12 gap 13 Pressed substrate 14 sub-area 15 Exclusions 16 cavity 17 Vacuum generation unit 18 angle 19 Depths 20 depth 21 Suction channel 22 Wave 23 Vacuum line 24 Nut 25 Drainage filter 26 heating elements 27 level 28 bearing rings 29 cover

Claims

1. A device (1) for producing a web from a fiber-containing material, in particular tissue paper, comprising - at least one endless belt (2) for supporting and transporting a fiber web (3); - at least one pressure roller (5), comprising: a longitudinal central axis (6), a lateral surface (9) extending between a first end face (7) and a second end face (8); as well as a radial direction (10), which radial direction (10) is arranged in the direction starting from the lateral surface (9) to the longitudinal central axis (6), and a direction of rotation (11), with respect to which direction of rotation (11) the pressure roller (5) is rotatably mounted; - wherein a gap (12) for pressing the fiber web (3) is formed between the at least one pressure roller (5) and the at least one endless belt (2); - at least one pressing substrate (13), in particular a pressing felt, for dewatering the fiber web (3), which pressing substrate (13) is guided in contact around at least a partial region (14) of the lateral surface (9) of the pressure roller (5); wherein the pressure roller (5) comprises multiple recesses (15) on the lateral surface (9), which recesses (15) are guided to at least one cavity (16) and open into the at least one cavity (16), which cavity (16) is arranged inside the pressure roller (5) with respect to the radial direction (10); and a vacuum generating unit (17) is provided, by means of which vacuum generating unit (17) a vacuum can be produced in the at least one cavity (16); characterized in that an axle (22) is arranged in the cavity (16), by means of which axle (22) the pressure roller (5) is rotatably mounted and in which axle (22) at least one vacuum line (23) is formed, which vacuum line (23) is connected to the vacuum generating unit (17).

2. The device (1) according to claim 1, characterized in that the recesses (15) are formed as channels, which channels are inclined at an angle (18) with respect to the radial direction (10) and that a channel inlet (32) is formed upstream of a channel outlet (33) with respect to the direction of rotation (11), wherein the channel inlet (32) is arranged on the lateral surface (9) and the channel outlet (33) opens into the at least one cavity (16).

3. The device (1) according to claim 1 or 2, characterized in that the recesses (15) have a rectangular cross-section perpendicular to the radial direction (10).

4. The device (1) according to one of claims 1 to 3, characterized in that the recesses (15) have step-shaped depressions (19) in the radial direction (10), wherein a depth (20) of the depressions (19) decreases in the radial direction (10) starting from the lateral surface (9) towards the longitudinal central axis (6).

5. The device (1) according to one of claims 1 to 4, characterized in that the cavity (16) is formed to be cylindrical and concentric with respect to the longitudinal central axis (6) and extends at least partially between the first and second end faces (7, 8).

6. The device (1) according to one of claims 1 to 5, characterized in that at least one suction channel (21) is arranged in the cavity (16), which suction channel (21) is formed in parallel to the longitudinal central axis (6) and is connected to the vacuum generating unit (17).

7. The device (1) according to one of claims 1 to 6, characterized in that the axle (22) has at least one groove (24) parallel to the longitudinal central axis (6), by means of which groove (24) the vacuum line (23) is operatively connected to the recesses (15) in some regions.

8. The device (1) according to claim 7, characterized in that the groove (24) is arranged in a region of the gap (12) with respect to the direction of rotation (11).

9. The device (1) according to claim 5, characterized in that at least one cover (29) is arranged in the cavity (16), which cover (29) is configured to seal multiple recesses (15) in some regions.

10. The device (1) according to one of claims 1 to 9, characterized in that multiple cavities (16) are formed in the pressure roller (5).

11. The device (1) according to claim 10, characterized in that the multiple cavities (16) are arranged at a constant radius (31) to the longitudinal central axis (6).

12. The device (1) according to one of claims 1 to 11, characterized in that the lateral surface (9) of the pressure roller (5) is heatable.

13. The device (1) according to one of claims 1 to 12, characterized in that a dewatering filter (25) is connected upstream of the vacuum generating unit (17), by means of which dewatering filter (25) a collected liquid can be returned to a system circuit.

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