EP2085515A2 - Device for dewatering tissue webs - Google Patents

Abstract

The device (100) has a dewatering device (101) with an endless, permeable structured band (4) e.g. spiral linking band, and an endless permeable dewatering band (5) e.g. filter band. Pressure applying units apply a pressure on the bands and between tissue webs (T) in a dewatering section (38). The pressure applying units exhibit mechanical filter pressing units (17) for applying the pressure that locally limits in circumferential direction and for applying pressure in material flow direction of the webs only in an inlet region (22) of the bands in the dewatering section at a suction roll (6).

Description

The invention relates to a device for the production of tissue webs, comprising a device for dewatering with an endless, permeable structured tape and, a suction roll partially circumferentially endless permeable Entwässerungsband, wherein the permeable structured band over a portion of its circulation path together with the permeable drainage tape is guided over at least a portion of the Umschlingungsbereiches the permeable drainage tape with the suction roll to form a dewatering section and means for applying a pressure on the two bands and the tissue web guided between them in this dewatering section.

Devices for draining tissue webs are known in a variety of prior art designs. In general, in the case of wet pressing processes, the fibrous web is compressed in a press nip in such a way that water is forced out of the fibrous web by the hydraulic pressure. In this case, only a small part of the roll circumference is used for the Kompressiervorgang the fibrous web in conventional press equipment, which is why the drainage time and place is severely limited. To overcome this drawback, efforts have been made to use a solid impermeable belt to form an elongated press nip for applying pressure to and dewatering the fibrous web. However, the non-permeable belt prevents the flow of drying fluid, such as air, through the fibrous web.

It is also known from the prior art to use a so-called "through-air drying process" (TAD) for drying the fibrous web, in particular tissue webs, in order to reduce the required mechanical pressing fraction. However, suitable cylinders are necessary for this process, as well as a complex air supply and heating system. The use of TAD systems is therefore very complicated and expensive. Furthermore, the operating costs are also very high, since it is necessary to dry the fibrous web to a higher degree of drying. The reason for this is the low transversal moisture profile achieved by the TAD system at low drying levels.

From the publication WO 2005/075736 There is previously known a device for dewatering a fibrous web which comprises a permeable structured strip which guides the fibrous web over a suction roll, a permeable dewatering belt which contacts the fibrous web and also passes over the suction roll and a mechanism for applying a pressure to the web permeable structured band, the fibrous web and the permeable dewatering band. In this case, the permeable structured band is preferably used simultaneously as the fibrous suspension receiving band by this is an endlessly circulating belt part of a former, which adjoins a headbox. The pulp suspension is introduced into a gap which is formed by the continuous circulating permeable and structured band and another endless circulating band in the form of a forming screen, wherein the permeable structured band wraps around a forming roller and the pulp suspension at least in the wrapping region of the permeable structured band with the forming roller is guided between the permeable structured band and the forming fabric. In this area, a very strong retention takes place, wherein following the forming roller, the two bands are separated from each other and the fibrous web is guided with the structured permeable belt to a mechanical screen press. The mechanism for applying a Pressure on the permeable structured band, the fibrous web and the permeable dewatering band in the region of the suction roll comprises an endlessly circulating, in particular permeable, band which presses against the inside of the permeable structured band in the area of the suction roll. The contact pressure is set by the belt tension, whereby the maximum achievable pressure is relatively small. In order to achieve correspondingly high compression pressures, a correspondingly high tension of the press belt is required, which in turn leads to an increase in the cost of the belts. Furthermore, additional pressing means acting on the press belt can be provided, which locally increase the contact pressure in the effective region of the press belt. Furthermore, a very large suction roller over the press nip area is required. Due to the size of a large negative pressure and large amounts of hot air are required because of the triple covering a very high heat loss occurs. The pressure generating band is exposed to very high temperatures, which must be considered in the design of the band. The high temperatures also lead to a reduction in the lifetime. Since the pressure generating band is within the loop of the endlessly circulating permeable structured band, the risk of a band break is very high. The investment and operating costs are very high, the same applies to the required exchange or change of the pressure applying band.

The invention is therefore based on the object, a device for dewatering fibrous webs, in particular tissue webs of the type mentioned by a mechanical pressing device further develop such that the disadvantages mentioned are avoided. In particular, the operating and investment costs are to be reduced and it should also be the known operations in the tissue production as previously possible with little effort.

The solution according to the invention is characterized by the features of claim 1. Advantageous embodiments are described in the subclaims.

The device according to the invention for producing a tissue web comprises a structured permeable tape and a permeable dewatering belt at least partially wound around a suction roll, wherein the suction roll is disposed within the permeable dewatering belt and the permeable structured belt in the belt area forming a dewatering section over a portion of the circulation path together with the permeable band is guided on the suction roll. There are provided means for applying a contact pressure in this dewatering section. These include according to the invention a device for applying a localized in the direction of passage pressure, in particular in the form of a pressure roller, which is arranged in the direction of passage of the tissue web in the inlet region in the dewatering section on the suction roll to form a press nip. The agents are free from a pressing pressure applying press belt.

According to the invention, the proportion of the mechanically generated dewatering in the inlet is thus increased in the dewatering section formed by the suction roll with the strips. The press nip is positioned such that it is preferably at the beginning of the suction zone. Due to the mechanical drainage routed at the beginning of the suction zone and the resulting moisture reduction on the tissue web, a subsequent drying of the drip following mechanical dehydration can become more effective. An additional heating of the bands is eliminated and the open flow area is increased here, since the entire wrap around the press nip downstream of the suction roll can be used to flow through.

According to a particularly advantageous embodiment, a flow-through drying device is arranged downstream of the press nip. This preferably comprises at least one hot-air blowing device which becomes effective on the inner periphery of the permeable structured band in the wrapping area on the suction roll. Preferably, the wrap area is identical at least to the theoretically possible suction zone or the suction zone is effective in the entire wrap area.

Due to the upstream mechanical dewatering due to the pressure roller, the range of flow drying can be reduced with the same dry result.

Since the highly stressed band has been dispensed with in comparison with the prior art embodiments, the mechanical load on the suction roll can be reduced. This is only embraced by the permeable drainage tape and it is also applied only over a short area in the wrap a contact pressure. The suction roll can thereby be made considerably smaller in terms of their dimensions. This leads to a saving of space, further it is possible to design the suction roll of the same design and dimensions as other suction rolls in the system, so that here only a single roll type must be kept in reserve, which is used in different areas in the device can get.

With regard to the configuration of the pressure roller there are a variety of possibilities. Preferably, however, a roller is selected which produces a soft press nip, that is to say a press nip, which is not only characterized by a line force but is slightly widened in the direction of passage. According to a first embodiment, this may be a conventional roller with a rigid shell, which is covered on the outer circumference with a correspondingly soft cover, which behaves elastically when acted upon or when the press nip is formed.

According to a further embodiment, it is conceivable to use a roll with deflection compensation. In this, a central support member is provided which is fixedly mounted and is guided rotatably about a jacket. The jacket is preferably highly elastic.

According to a further third embodiment, the pressure roller can also be designed as a shoe press roll. This is characterized by a flexible endless revolving roll shell, on the inner circumference of a stationary shoe can be pressed.

The design of the pressing element according to one of the possibilities offers the advantage that it can be used here on standardized pressure rollers. The slightly extended press nip leads overall to lower forces due to the increased contact surface.

The contact pressure by the pressure roller is controlled depending on the type of construction in a simple manner. The controllability can be carried out both across the width transverse to the tissue web running direction, wherein the control preferably takes place at least zone-wise, very particularly preferably steplessly over the entire width. This makes it possible to influence the moisture cross profile over the tissue web width.

The solution according to the invention is characterized by the more intensive mechanical dehydration at the beginning of the dewatering zone by a reduction of the energy input. The water content in the web before beginning the throughflow drying is reduced. By dispensing with the highly loaded pressure belt, a better air passage between the two in the drainage section operatively connected bands can be done. It is necessary with the same drainage a lower vacuum level and exhaust air volume for the flow drying.

In addition to the arrangement of the throughflow drying device in the region of the suction zone of the suction roll of the device for applying a contact pressure, it is also possible to associate these upstream of the drying device and the device downstream suction roll. As a result, the tissue web no longer cools down on the way to the drying device, whereby an energy saving due to the no longer required high dry power input into the tissue web is achieved.

According to a particularly advantageous embodiment, the device is laid for dewatering in the area of the drying device, resulting in a particularly compact design in the machine direction. The distance between the bearing axis of the suction roller wrapped by the permeable drainage belt and the drying device, in particular the drying cylinder or a through-flow drying cylinder in the machine direction, is ≦ 5 m, preferably between 2 and 3 inclusive.

For safe railway acquisition of the device for dewatering a suction device is arranged downstream.

According to a particularly advantageous embodiment, the guide rollers are arranged such that readily the pressing device can be removed from the web pass and a simple conversion and pivoting to form a normal Crescentformers is possible.

Figur 1a

verdeutlicht in schematisiert vereinfachter Darstellung eine erste Ausführung einer erfindungsgemäßen Vorrichtung zur Herstellung einer Tissuebahn;

Figur 1b

verdeutlicht eine Detailansicht gemäß Figur 1a;

Figuren 2a und 2b

verdeutlichen mögliche Ausführungen der Anpresswalze;

Figur 3

verdeutlicht eine Weiterentwicklung gemäß Figur 1 a;

Figur 4

verdeutlicht anhand eines Ausschnittes gemäß Figur 1b eine besonders vorteilhafte Ausgestaltung der Anpresswalze als Saugpresswalze;

Figur 5

verdeutlicht beispielhaft eine mögliche Ausführung der Saugwalze mit zwei hintereinander geschalteten Saugzonen;

Figur 6

verdeutlicht eine besonders vorteilhafte Weiterentwicklung einer Ausführung gemäß Figur 3;

Figur 7

verdeutlicht eine vorteilhafte Weiterentwicklung einer Ausführung gemäß Figur 6.

The solution according to the invention is explained below with reference to figures. It details the following:

FIG. 1a

illustrates in schematic simplified representation of a first embodiment of a device according to the invention for producing a tissue web;

FIG. 1b

clarifies a detail view according to FIG. 1a ;

FIGS. 2a and 2b

clarify possible embodiments of the pressure roller;

FIG. 3

clarifies a further development according to FIG. 1 a;

FIG. 4

clarified by a section according to FIG. 1b a particularly advantageous embodiment of the pressure roller as Saugpresswalze;

FIG. 5

exemplifies a possible embodiment of the suction roll with two suction zones connected in series;

FIG. 6

illustrates a particularly advantageous development of an embodiment according to FIG. 3 ;

FIG. 7

illustrates an advantageous development of an embodiment according to FIG. 6 ,

The FIG. 1a illustrates in a simplified schematic representation of the basic structure of an inventively designed device 101 for dewatering fibrous webs, especially tissue webs T in a machine 100 for producing such a fibrous web, in particular tissue web T. The machine 100 comprises a headbox 1, which is a forming unit 15 upstream. The forming unit 15 comprises two endlessly circulating belts, in particular sieve belts. A first screen belt is designated 2 and acts as a forming screen. The second band is designed as a permeable structured band 4. This is guided by guide rollers 12. Both bands are guided over a portion of their circulation path via a forming roller 3 together to form an inlet gap 14 for the introduced over the headbox 1 pulp suspension S and form in Umschlingungsbereich 16 with the forming roller 3 a first dewatering section in which the pulp suspension S due to the voltage between the two bands 2, 4 is dewatered around the forming roller 3 at this. The forming roller 3 can be carried out for this purpose preferably also sucked. The screen belts 2 and 4 are separated from each other after the belt 16, wherein the resulting from the pulp suspension S fibrous web, in particular tissue web T, with the permeable structured band 4 on the device 101 to a drying device 18, in particular a heated drying cylinder 8 in Shape of a so-called Yankee cylinder or through-flow drying to be led. For this purpose, the device 101 comprises a device 36 for applying a locally localized pressure in the passage direction, in particular a press device 17, through which the tissue web T is guided with the permeable structured band 4. The tissue web T is transferred to the press device 17 downstream of the permeable structured belt 4 to the drying cylinder 8. The mechanical press device 17 is formed by a suction roll 6, which is arranged within an endless permeable dewatering belt 5 and is looped around by it in a partial region of its outer circumference, as well as a pressure roller 9. The wrapping area is designated 37. The permeable structured band 4 is guided together with the permeable dewatering belt 5 over a partial region of its circulation path, wherein this partial region at least partially encloses the wrap-around region 37 of the suction roller 6. This section of the common guide describes a dewatering section 38. The design is free of a press belt. The press belt known from the prior art is here replaced by a counter roller in the form of the pressure roller 9, which forms a press nip 19 with the suction roller 6. The suction roller 6 is either driven or indirectly driven by the drive of the permeable dewatering belt 5 with. The suction roll 6 comprises for this purpose a rotatably mounted roll shell 20, which is rotatable about at least one fixed stationary suction zone 21. The press nip 19 is positioned such that, viewed in the direction of passage of the tissue web T, it is arranged in the inlet region of the dewatering section 38 and thus the common guidance of the belts 4, 5, preferably viewed in the direction of passage of the tissue web T in the inlet region 22 into the suction zone 21 the mechanical dewatering in the initial area, in particular inlet region 22 of the suction zone 21 moves. Due to the consequent reduction of the moisture content, a downstream flow drying device 23 can be better effective. A strong heating of the permeable structured strip 4 is eliminated and the open flow area for the through-flow drying device 23 is increased, in particular on the permeable structured band 4. Opposite the conventional solution with generation of the pressing pressure over an endlessly circulating belt, this arrangement is free of one, a contact pressure generating endlessly circulating belt, so that the mechanical pressing device 17 alone in the usual way by two operatively engageable rotatable surfaces is formed, between which to draining tissue web T is preferably passed between two endlessly circulating belts, here the permeable structured belt 4 and a permeable drainage belt 5.

Subsequent to the pressure roller 9, a flow drying device 23 is provided, preferably in the form of a hot air blow box 10. This is preferably immediately downstream of the press nip 19 in the direction of passage and still effective in the extension region of the suction zone 21 with respect to the suction roll 6. The range of action of the throughflow drying device 23 viewed in the direction of passage of the web can be considerably reduced due to the displacement and intensification of the mechanical dewatering at the beginning, in particular inlet region 22 of the suction zone 21 of the suction roller 6. Due to the elimination of the highly loaded press belt, the mechanical load on the suction roller 6 and the required amount of vacuum air are also greatly reduced, so that the suction roller 6 can be reduced in size with the same drainage performance and thus identical to other suction rolls, such as a tissue web T leading and transferring suction roll 7 are performed on the heatable drying cylinder 8. Furthermore, the local press nip load by the pressure roller 9 is much lower than the resultant force from the looping when forming the contact pressure via a press belt.

According to an advantageous embodiment, after passing through the press device 17, the tissue web T is continued with the permeable structured band 4 and transferred to a heatable drying cylinder 8. This takes place in the region of a press nip 30 formed therewith, which in the case illustrated comprises a suction roll 7 and the outer circumference 31 of the Drying cylinder 8 is formed. The suction roll 7 also has at least one suction zone 32, which is arranged upstream of the press nip 30 in the guide direction of the tissue web T and thus before the entry into this safe guidance of the fibrous web, in particular tissue web T on the suction roll 7 and thus a proper transfer to the Drying cylinder 8 guaranteed.

The FIG. 1b clarifies again in an enlarged view with reference to a detail view from the FIG. 1a the execution of the mechanical press device 17 according to the invention with downstream flow drying device 23 of the suction roller 6 is arranged below a water collecting tray 39 in an advantageous manner.

The design of the pressure roller 9 can take many forms. Preferably, this is designed and executed such that it is suitable for forming a so-called soft press nip 19. In the simplest case, the pressure roller 9 can according to FIG. 2a from a roll having a rigid roll shell 25 provided with an elastic cover 26.

According to another embodiment in FIG. 2b it is conceivable to form the pressure roller 9 as a deflection compensating roller 13, for example with a rotatably mounted and driven elastic sheath 28, which is supported on a central support member 40 via means for deflection compensation, in particular pressing elements 41. For controlling the contact force, a corresponding adjusting device 42 is provided.

Figure 2c illustrates an embodiment of the pressure roller 9 designed as a shoe press roll 27. The shoe press roll 27 is characterized by a flexible rotatable roll shell 43 which can be pressed against the suction roll 6 via a press shoe 24, which becomes effective on the inner circumference.

Opposite the execution in FIG. 1a clarifies the FIG. 3 By way of example, another particularly advantageous embodiment of the pressure roller on the drying cylinder 8 as a shoe press roll 33. Preferably, the shoe press roll 33 is upstream of the suction roll 7, to ensure optimum guidance and adherence to the structured permeable tape 4 to the transfer area on the drying cylinder 8.

The FIG. 4 illustrates a further development of the detail view according to FIG. 1 b. In this, the pressing force applying pressure roller 9 is designed as a suction press roll 34. This comprises a rotatable roll shell 44 which is rotatable about a stationary suction zone 35. The stationary suction zone 35 is arranged such that it is preferably arranged upstream of the press nip 19 and does not form any overlap with the suction zone 21 on the suction roll 6. The region of the suction zone 35 is looped around by the structured permeable band 4. As a result, the press nip 19 is virtually ventilated via the pressure roller 9. However, the covering, in particular the further second band 5 supporting the tissue web T in the form of the permeable dewatering belt, is here already carried in the region of the suction zone 35 on the pressure roller 9 before it enters the press nip 19.

In the embodiments according to the FIGS. 1 to 4 the course of a Crescentfilzbandes 11 is also shown by a broken line. The device 101 can be used free of the press device 17 as a conventional crescent machine for smooth tissue types.

The solution according to the invention is not on in the FIGS. 1 to 4 limited embodiments shown. In particular, the individual components, in particular the suction rolls 6, 7 or also the suction press roll 9 designed as a pressure roll, can be embodied in various ways. Conceivable are embodiments with only one suction zone, which extends viewed in the direction of rotation of the roll shell over a portion of the circumference or with a plurality of zones connected in series.

An execution with only one zone is in the FIGS. 1 to 4 shown. An embodiment with more than one zone, preferably two suction zones 21I, 21II, is exemplary in the FIG. 5 reproduced by the example of the suction roller 6. In this case, the vacuum in the first zone 21I is preferably greater than in the second zone 21II. The pressure roller 9 is arranged opposite to the first zone 21I, while the second zone 21II can be flowed through by a hot fluid, for example hot air or unsaturated steam, through the flow-through drying device 23.

The FIG. 6 illustrates a particularly advantageous development of an embodiment according to FIG. 3 Preferably, the shoe press roll 33 is arranged upstream of the suction roll 7 in order to provide optimum guidance and adhesion to the structured permeable tape 4 up to the transfer area, in particular the space formed between the pressure roll and the drying cylinder 8 To ensure transfer gap on the drying cylinder 8. The same reference numbers are used for the same elements. In this embodiment, however, the arrangement of the device 101 for dewatering, in particular the means for applying a pressure on the two belts 4, 5 in the form of the device 36 takes place immediately in front of the inside of the loop formed by the permeable structured band 4 suction roll 7. The structure the device 36 takes place in analogy to FIG. 1a and 3 from a suction roller 6 acting as a suction roller and a pressure roller 9, which preferably forms a press nip 19 in the region of the inlet 22 into the suction zone 21 or within this with the suction roller 6. The through-flow drying device 23 is here not associated with the suction roll 6 and thus immediately downstream of the press nip 19, but the device 36 downstream and within the loop formed by the permeable structured band 4 arranged suction roll 7, in particular their suction zone 32. The distance X between drying device 18, in particular the bearing axis L8 of the heated drying cylinder 8 or a flow-through cylinder and with the axis of rotation of the Roll mantle of the suction roller 6 coincident bearing axis L6 in the machine direction MD is ≤ 5m, preferably between 2 and 3m including. Preferably, however, a suction device 45 is disposed downstream of the press nip 19 for the secure transfer of the tissue web T through the permeable structured belt 4.

In contrast clarifies FIG. 7 a particularly advantageous further development according to FIG. 6 with design of the suction roller 7 as a pressure roller on the drying cylinder 8. This design is characterized by a low number of components and low space requirement. Again, the Durchströmungstrocknungseinrichtung 23 is not immediately downstream of the press nip 19, but the suction of the suction roller 7 and thus in the drying cylinder 8th

LIST OF REFERENCE NUMBERS

1

headbox

2

Tape, in particular sieve tape

3

forming roll

4

permeable structured band

5

permeable drainage tape, felt or sieve

6

suction roll

7

suction roll

8th

heated drying cylinder

9

pressure roller

10

Heisluftblaskasten, heating element

11

Crescentfilz

12

guide roll

13

Deflection roll

14

inlet gap

15

forming unit

16

wrap region

17

mechanical screen press

18

dryer

19

press nip

20

coat

21

suction zone

22

intake area

23

Flow drying device

24

press shoe

25

roll shell

26

reference

27

Shoe press roll

28

roll shell

30

press nip

31

outer periphery

32

suction zone

33

Shoe pressing device

34

suction press

35

suction zone

36

Device for applying a contact pressure

37

wrap region

38

dewatering section

39

Water trough

40

supporting body

41

Means for deflection compensation

42

setting device

43

roll shell

44

roll shell

45

suction

S

Fibrous suspension

T

tissue web

F

Fibrous web

L6

bearing axle

L8

bearing axle

X

distance

100

Machine for producing a fibrous web, in particular tissue web

101

Device for dewatering fibrous webs

Claims (29)

Apparatus (100) for making tissue webs (T), comprising a device (101) for dewatering with an endless, permeable structured belt (4) and a continuous permeable dewatering belt (5) partially encircling a suction roll (6) the permeable structured band (4) is guided over a portion of its circulation path together with the permeable dewatering band (5) over at least a portion of the Umschlingungsbereiches (37) of the permeable dewatering belt (5) with the suction roll (6) to form a dewatering section (38) and means for applying a pressure to the two belts (4, 5) and the tissue web (T) guided between them in this dewatering section (38),
characterized,
in that the means comprises, in the direction of passage of the tissue web (T), only in the inlet region (22) of the bands (4, 5) into the dewatering section (38) on the suction roll (6) in the circumferential direction of this pressure-applying device (36) , Device (100) according to claim 1,
characterized,
that the device (36) arranged one at the inner periphery of the permeable structured belt (4) pressure roller (9) in the passage direction of the tissue web (T) in the inlet region (22) into the drainage portion (38) of the suction roll (6) to form a press nip (19) is arranged. Device (100) according to claim 1 or 2,
characterized,
in that the device (36) comprises a pressure roller (9) arranged on the inner circumference of the permeable structured belt (4) which, in the direction of passage of the tissue web (T) in the initial region of the suction zone (21) in the dewatering section (38) on the suction roller (6) Forming a press nip (19) is arranged. Device (100) according to one of claims 1 to 3,
characterized,
in that a through-flow drying device (23) is arranged downstream of the press nip (19) in the direction of passage of the tissue web (T). Device (100) according to claim 4,
characterized,
in that the flow-through drying device (23) comprises at least one hot-air blowing device (10) which is arranged on the suction roll (6) on the suction roll (6) on the inner circumference of the permeable structured strip (4) in the dewatering section (38) of the two strips (4, 5). Device (100) according to one of Claims 2 to 5,
characterized,
in that the press nip (19) formed between the pressure roller (9) and the suction roller (6) is designed as a soft press nip. Device (100) according to claim 6,
characterized,
that the pressure roller (9) comprises a rigid roll cover (25) or roller body which is provided on the outer circumference (24) having a resilient covering (26). Device (100) according to claim 6,
characterized,
in that the pressure roller (9) is designed as a deflection compensating roller (13), comprising a stationary support body (40) and an elastic roll shell (28) rotatable about the latter and arranged by means of at least one between the support body (40) and the roll shell (28) Actuating device (42) controllable means (41) for deflection compensation on the support body (40) is supported. Device (100) according to claim 6,
characterized,
in that the pressure roller (9) is designed as a shoe press roll (27), comprising a flexible rotatable roll shell (43) and a stationary stationary shoe (24) which can be pressed against the inner periphery of the flexible, rotatable roll shell (43). Device (100) according to claim 6,
characterized,
in that the pressure roller (9) is designed as a suction pressure roller (34) comprising at least one suction zone (35) which is arranged upstream of the suction roller (6) in the direction of passage of the tissue web (T) on the suction roller (6). Device (100) according to one of claims 2 to 10,
characterized,
that the contact pressure of the pressure roller (9) over the width of the press nip (19) viewed perpendicular to the direction of passage of the tissue web (T) is controllable. Device (100) according to claim 11,
characterized,
that the pressing force is controlled zone by zone. Device (100) according to one of claims 1 to 12,
characterized,
in that the suction roller (6) looped around by the permeable dewatering belt (5) comprises at least one suction zone (21) and the suction zone (21) is arranged at least partially in the looping area (37). Device (100) according to one of claims 1 to 13,
characterized,
that the permeable dewatering belt (5) looped around the suction roll (6) considered more in the direction of passage of the tissue web (T) arranged behind one another can be acted upon different suction zones (21I, 21II) comprising. Device (100) according to claim 14,
characterized,
that the press nip (19) is disposed between the pressure roller (9) and a suction roll (6) in the area of the first suction zone (21I) in the region of the inlet of the tissue web in the dewatering section (38). Device (100) according to claim 15,
characterized,
that the through air drying means (23) of the second zone (21II) is assigned and these through which a liquid or gaseous medium. Device (100) according to one of claims 2 to 16,
characterized,
in that this comprises a heatable drying unit (18) arranged downstream of the press nip (19) and the throughflow drying device (23) for forming a press nip (30) with a pressure roll (33) or suction roll (7) arranged in the permeable structured band (4). Device (100) according to claim 17,
characterized,
that the suction roller (7) forming the second press nip (30) is of identical design to the suction roll (6) in the permeable dewatering belt (5) in terms of its design and dimensioning. Device (100) according to one of claims 17 or 18,
characterized,
that the second suction roll (7) comprises one or more suction zones. Device (100) according to claim 17,
characterized,
that the second pressure roller (33) is designed as a shoe press roll. Device (100) according to one of claims 1 to 20,
characterized,
that this comprises a headbox (1) and a forming fabric (2), which is guided together to form a gap (14) over a partial region of the circulation path with the permeable structured band (5). Device (100) according to one of claims 1 to 21,
characterized,
that the permeable dewatering belt (5) is constructed as a sieve belt. Device (100) according to one of claims 1 to 21,
characterized,
in that the permeable dewatering belt (5) is designed as a felt belt. Device (100) according to claim 23,
characterized,
that the felt is formed multi-layered. Device (100) according to one of claims 1 to 24,
characterized,
that the permeable structured band is formed as a spiral link belt. Device (100) according to one of claims 1 to 25,
characterized,
is carried out that the arrangement of the guide rollers (12) for the permeable structured belt (4) and / or the permeable dewatering belt (5) adapted to be suitable, instead of this belt or these belts a Crescentfilz bypassing the device (36) to to lead. Device (100) according to one of claims 4 to 26,
characterized,
in that the flow-through drying device (23) is associated with the suction roll (7). Device (100) according to claim 27,
characterized,
that the distance (X) between the bearing axis (L6) of the permeable dewatering belt (5) looped around the suction roll (6) and (L8) of the drying device (18), in particular the drying cylinder (8) or a through-flow drying cylinder in the machine direction (MD) ≤ 5m , preferably between 2 and 3 m inclusive. Device (100) according to one of claims 27 or 28,
characterized,
in that the device (101) is followed by a suction device (45) for safe web transfer to the permeable structured belt (4).

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