EP2288749A1

EP2288749A1 - Installation for producing a fibrous-material web

Info

Publication number: EP2288749A1
Application number: EP09753850A
Authority: EP
Inventors: Günter MEUSER
Original assignee: Voith Patent GmbH
Current assignee: Voith Patent GmbH
Priority date: 2008-05-29
Filing date: 2009-05-25
Publication date: 2011-03-02
Anticipated expiration: 2029-05-25
Also published as: ATE535643T1; WO2009144195A1; US20110005699A1; CN102046879B; EP2288749B1; CN102046879A; DE102008002087A1; US8152968B2

Abstract

A machine for the production of a fibrous web including a fibrous stock suspension unit for the production of an aqueous suspension, a web former for dewatering the aqueous suspension and forming the fibrous web including at least one inclined wire progressing, at least in sections, at an angle to horizontal and at least one single layer headbox, one binder wire section progressing substantially horizontally and including at least one binder headbox, one drying unit including a drying wire, one winder, and at least one blowing device positioned between the binder wire section and the drying unit for contactless floating guidance of the fibrous web by one of air and another free flowing medium, wherein the blowing device includes a plurality of blowing zones transverse to a direction of travel of the fibrous web, the blowing zones configured to be controlled/adjusted independently of each other.

Description

Plant for producing a fibrous web

The invention relates to a plant for producing a fibrous web, in particular a long fiber paper or wet nonwoven web comprising a Faserstoffsus- pendipereinheit for producing an aqueous suspension of all components, a web forming agent for dewatering the aqueous suspension and for forming the fibrous web, which at least in sections at an angle to the horizontal slanted screen and at least one at least single-layer, preferably multi-layer headbox, a Bindersiebpartie for applying an aqueous binder on the fibrous web having at least partially horizontally or approximately horizontally extending binder wire and at least one Binder, a drying wire having a drying unit for drying and Solidification of the fibrous web and a rewinder for the continuous winding of the fibrous web on hubs to bobbins.

Such a plant for the production of a fibrous web, in particular a long fiber or wet nonwoven web and the thus applicable methods for producing the same, the so-called wet process, have been part of the known state of the art for several decades.

In these wet processes, in a pulp suspension unit, for example, a glass fiber slurry becomes a typical white water in a pulper for dispersion by adding a glass fiber having a fiber length in the range of 6 to 40 mm, preferably 8 to 30 mm, especially 10 to 25 mm the glass fiber in the white water forming the Fiberglass slurry having a fiber concentration of about 0.2 to 1.0 percent by weight, and assigned to a white water stream. This fiberglass slurry is then applied and dewatered in a web former having at least one at least one layered, preferably multilayer headbox on an inclined screen extending at least in sections at an angle to the horizontal. The dewatering of the glass fiber slurry forms a fiberglass wet web. The fiberglass wet web formed is then transferred to an at least partially horizontally or approximately horizontally extending binder wire a Bindersiebpartie. In this binder wire section, at least one aqueous binder, such as an aqueous urea-formaldehyde (UF) resin-based binder, is applied to the wet fiberglass wet mat by means of at least one binder bake. Subsequently, the excess binder is sucked off. The aqueous binder solution is preferably applied to the wet fiberglass wetlaid using a curtain coater or a swap and squeeze applicator, but other application methods such as spraying are also suitable. The wet and still unglued fiberglass wet web is then transferred to a drying unit having a drying wire for drying and curing (polymerization) of the binder, which glues the glass fibers together in the glass fiber nonwoven. The drying unit may for example have a heated continuous furnace or a drum or belt dryer, wherein the glass fiber nonwoven is usually exposed to a temperature of 100 to 250 ⁰ C, but not more than 1 to 2 minutes. And finally, a surface mass range of 40 to 200 g / m ² and a binder content of 10 to 30% having fiberglass nonwoven wound in a winder on hubs to winding rollers to then subsequent processing or processing stations can be supplied.

The transfer of the wet and still unglued fiberglass web from the Bindersiebpartie in the drying unit is sometimes carried out by means of a longitudinally corrugated, chrome-plated and provided with its own drive roller. Here- There is a constant risk that the roller, as soon as it comes into contact with the very wet and sticky fiberglass wet fleece due to the binder application, very quickly contaminated with glass fibers. This contamination causes a high loss of production and a concomitant poor runnability, since the system must be completely turned off and the roller fouled with glass fibers must be cleaned. Occasionally, although constructions are used for the purpose of "on-line" roller cleaning, the achievable cleaning results are more than unsatisfactory, both in terms of cleaning quality and cleaning times.Also, the cost of such constructions, including the need for a spare reserve spare parts , usually not negligible.

The roll is also not positioned at the current production speeds of up to 350 m / min, since this is not required for these production speeds. It can be seen, however, that the fibrous web consisting of the glass fiber wet nonwoven undergoes a "troubled" run in this transfer region and thus an obstacle to a future increase in production speeds could exist.

The invention has for its object to provide an improved suction device of the type mentioned, which avoids the disadvantages of the prior art as far as possible, preferably completely. In particular, the transfer of the wet and still unglued fibrous web from the Bindersiebpartie in the drying unit should be made more reliable, so that it does not adversely affect the runnability of the system and does not represent a barrier to a future increase in production speeds.

This object is achieved in a plant of the type mentioned in the present invention that between the Bindersiebpartie and the Trocknungsein- unit at least one preferably adjustable blower for contactless floating control of the fibrous web by means of air or another flowable medium is provided which has transversely to the direction of the fibrous web a plurality of independently controllable blowing zones.

The object of the invention is completely solved in this way.

The provision of this blowing device for the contactless floating control of the fibrous web permits a process-reliable production of a fibrous web, in particular a long fiber paper or wet nonwoven web.

Due to the generation of a floating cushion by the blowing device, the possibility of any contamination of a component or an assembly as far as possible, even completely avoided. As this eliminates the need for expensive and time-consuming cleaning activities with sophisticated cleaning equipment, it can achieve significantly higher runnability and lower plant operating costs.

The levitation pad created by the blowing device also ensures significant stabilization of the fibrous web in this transfer area, which can ultimately have a positive effect on a possible increase in production speeds.

And the mentioned blowing zones, which are controllable independently of one another transversely to the running direction of the fibrous web, permit optimum and efficient operation of the blowing device across the width of the fibrous web.

In a first embodiment according to the invention, the blowing device has a housing extending at least over the width of the fibrous web, which is connected to at least one preferably controllable blower for generating a levitation cushion and which has a boundary wall whose outer wall surface serves as a guide surface for the pulp preferably curved path and having a plurality of outlet openings for the air or the other fluid medium. This ensures both floating and stabilized guidance of the fibrous web around the outer boundary surface of the housing. The targeted formation of the air cushion, for example, due to the prevailing fan performance, and / or the selected curvature of the outer wall surface as a guide surface for the fibrous web can be selectively influenced on the leadership of the fibrous web.

So that a uniform formation of the air cushion as well as simultaneous or approximately simultaneous admission of the fibrous web takes place with air or the other flowable medium, the outlet openings for the air or other fluid medium are preferably arranged in at least one transverse to the direction of the fibrous web series. It is particularly advantageous if the outlet openings for the air or the other fluid medium are arranged in two transverse to the direction of the fibrous web rows, wherein the first row of outlet openings in a arranged in the inlet region of the housing air duct and the second row of outlet openings is provided in a arranged in the outlet side region of the housing air duct and wherein the provided in the two air channels outlet openings are directed to the center plane of the housing. As a result, experiences the fibrous web over a longer range.

Furthermore, it can be provided that a cover plate is arranged in the inlet-side region of the housing and / or in the outlet-side region of the housing, which extends from the housing in the direction of the fibrous web and at a distance between 5 and 30 mm, preferably between 10 and 25 mm , ends from the fibrous web and which extends substantially over the entire width of the fibrous web. This ensures, among other things, that the fibrous web in a stable web run, so without flapping on the Guiding surface of the blower runs up and leaves them again so. One reason for this is that the cover plate leads to a stabilization of the air flow and thus prevents fluttering of the fibrous web. The cover plate may be attached to the housing and / or be adjustably mounted in the direction of the fibrous web. These two options allow adaptation to different operating conditions.

With regard to an optimal arrangement of the blowing device, in its working position it can have an adjustment range with respect to the horizontal of +50 to -80 mm, preferably +30 to -50 mm, in particular +20 to -30 mm. Thus, it can be employed more or less in the course of the fibrous web to be transferred, whereby optionally a process-safe guidance of the fibrous web can be achieved.

Thus, the levitation cushion can be produced in sufficient quantity, the blowing zones a plurality of independently controllable / adjustable having blowing means preferably an air volume flow rate in the range of 20 to 300 m ³ / min ^»m, preferably from 30 to 250 m ³ / ^min» m, in particular from 50 to 200 m ³ / min ^" m, and / or an air pressure in the range of 0.02 to 3.0 bar, preferably from 0.05 to 2 bar, on.

Moreover, the blowing device is preferably positionable between the working position and a rest position by means of at least one positioning device, in particular pivotally mounted by means of at least one pivoting device. This storage allows, as needed, good accessibility to the blowing device and its components.

Also, the plant and its between the Bindersiebpartie and the between

Drying unit provided blowing device preferably for a fibrous web having a width in the range of 2,000 to 6,000 mm, preferably from 3,000 to 6,000 mm, in particular from 4,500 to 6,000 mm, and for a maximum Production speed of up to 600 m / min designed. Especially in these width ranges, the process-reliable stabilization of the fibrous web is fully effective.

Further features and advantages of the invention will become apparent from the following description of a preferred embodiment with reference to the drawings.

1 shows a schematic layout of a plant for producing a

Fibrous web according to the prior art;

Figure 2 is a schematic side view of a blowing device according to the invention and arranged between the binder wire section and the drying unit in its working position; Figure 3 is a schematic side view of a blowing device according to the invention and arranged between the Bindersiebpartie and the drying unit in its rest position;

FIG. 4 shows the blowing device shown in FIG. 2 and in its working position according to the detailed view X; and FIG. 5 shows the blowing device according to the view Y shown in FIG. 2 and in its working position.

1 shows a schematic layout of a plant 1 for producing a fibrous web 2, in particular a long fiber paper or wet nonwoven web.

This plant 1 for the production of the fibrous web 2 comprises a fiber suspension unit 3, a web forming 4, an at least partially at an angle α to the horizontal H extending inclined wire 5 and at least one at least one layer, preferably multi-layer headbox 6, a Bindersiebpartie 7, the at least partially horizontally or approximately horizontally extending Bindersieb 8 and at least one Binder headbox 9 has a dryer unit 11 having a drying unit 10 and a rewinder 12 for continuously winding the fibrous web 2 on hubs 13 to 10 Wickerollen.

In the pulp suspension unit 3, all components required for the preparation of an aqueous suspension, such as water, chopped fibers, binders and the like, are also introduced into a first container ("pulper") 15 provided with an agitator 16 and then into a second one given an agitator 18 container ("pulper") 17; the aqueous suspension can be carried by the pumps 19, 20. The aqueous suspension can be, for example, a glass fiber slurry containing glass fibers with a fiber length in the range from 6 to 40 mm, preferably from 8 to 30 mm, in particular from 10 to 25 mm. and so-called white water and has a fiber concentration of about 0.2 to 1, 0 weight percent.

The pulp suspension unit 3 is followed by the next stage of the process, namely the dewatering of the aqueous suspension and the formation of the fibrous web 2 with the aid of the inclined screen 5 arranged in the web former 4. For this purpose, the aqueous suspension is applied to the inclined screen by means of an at least single-layered, preferably multilayer headbox 6 5 applied. The water filtered off from the aqueous suspension below the inclined screen 5 is recirculated according to the arrow 21 and admixed, for example, with the aqueous suspension leaving the second container ("pulper") 17 of the pulp suspension unit 3.

In the following process step, at least one aqueous binder, such as, for example, an aqueous urea-formaldehyde (UF) resin-based binder, is applied by means of a binder casserole 9 to the still wet fibrous web 2 resting on the binder wire 8 of the binder wire section 7. In this Bindersiebpartie 7 then the excess binder is also removed by suction in a known manner. The aqueous binder can in not shown Way can also be applied using a curtain coater or a Tauschund squeeze applicator on the still-fibrous web, but other application methods such as spraying are suitable.

The next stage of the process is used to dry and solidify the still wet fibrous web 2 by curing (polymerization) of the binder, which glues the glass fibers together in the glass fiber fleece. For this purpose, it is guided through the drying wire 10 having the drying unit 10, which has two heated and illustrated continuous furnaces 22 or a drum or belt dryer, not shown. The fibrous web 2 is in this case usually exposed to a temperature of 100 to 250 ⁰ C, but not longer than 1 to 2 minutes.

And in a final stage of the process, the fibrous web having a basis weight range of 40 to 200 g / m ² and binder content of 10 to 30% is wound in the reel-up 12 onto winding cores 14 to form winding rolls 13, to be fed to subsequent processing stations can.

Between the binder wire section 7 and the drying unit 10, an adjustable blowing device 23 for contactless floating control of the fibrous web 2 by means of air 24 or another fluid medium 25 is now provided, which is independent of the direction L (arrow) of the fibrous web 2 transversely from each other controllable blowing zones 26.1 to 26.5 (see Figure 5).

FIG. 2 now shows a schematic side view of the blowing device 23 arranged between the binder wire section 7 and the drying unit 10 in its working position A, while FIG. 3 shows the blowing device 23 in its rest position R. The positioning of the blowing device 23 between the working position A and a rest position R is carried out by means of at least one positioning Device 27. The positioning device 27 embodied as a swiveling device 28 is here articulated both on the drying unit 10 and on the blower device 23 having a housing 30. Such a pivoting device 28 is well known to those skilled in the art and includes, for example, a hydraulic or pneumatic swing cylinder 29. The fibrous web 2 has a web running direction L (arrow) and the binder wire section 7 comprises a binder wire 8, whereas the drying unit 10 comprises a drying wire 11.

FIG. 4 shows the blowing device 23 shown in FIG. 2 and located in its working position A in accordance with the detailed illustration X.

The blowing device 23 has a housing 30 which extends at least over the width B (arrow) of the fibrous web 2 and which is connected to at least one preferably controllable blower 31 (arrow illustration) for producing a floating pad 32. It also has a boundary wall 33, the outer wall surface 34 is curved as a guide surface 35 for the fibrous web 2 and a plurality of outlet openings 36 for the air 24 or the other flowable medium 25 has. The outlet openings 36 may be performed in a known manner as a simple holes, but they can also be provided with nozzle inserts.

The outlet openings 36 for the air 24 or the other fluid medium 25 are arranged in two transverse to the direction L (arrow) of the fibrous web 2 extending row R1, R2. The first row R1 at outlet openings 36 is provided in an air duct 38 arranged in the inlet-side area 37 of the housing 30, and the second row R2 at outlet openings 36 is provided in an air duct 40 arranged in the outlet-side area 39 of the housing 30. In addition, the provided in the two air channels 38, 40 access openings 36 are directed to the center plane M of the housing 30 out. Furthermore, a cover plate 41 is arranged both in the inlet-side region 37 of the housing 30 and in the outlet-side region 39 of the housing 30, which extends from the housing 40 in the direction of the fibrous web 2 and at a distance a between 5 and 30 mm, preferably between 10 and 25 mm, ends of the fibrous web 2 and which extends substantially over the entire width B (arrow) of the fibrous web 2. The single cover plate 41 is fixed to the housing 30 and mounted adjustable in the direction of the fibrous web 2. The respective displacement is indicated by a double arrow.

In its illustrated working position A, the blowing device 23 has an adjustment range S with respect to the horizontal h of +50 to -80 mm, preferably of +30 to -50 mm, in particular of +20 to -30 mm. Thus, it can be set more or less in the course of the fibrous web 2 to be transferred, as a result of which process-reliable guidance of the fibrous web 2 can optionally be achieved.

Also, the blower several independently controllable / regulatable blowing zones 23 having 1.26 to 5.26 (see FIG. 5) has an air volume flow rate V (arrow) in the range of 20 to 300 m ³ / min ^»m, preferably from 30 to 250 m ³ / min ^» m, in particular from 50 to 200 m ³ / min ^» m, and an air pressure p in the range of 0.02 to 3.0 bar, preferably from 0.05 to 2 bar, on.

FIG. 5 shows the blowing device 23 shown in FIG. 2 and located in its working position A according to the view Y.

The five independently controllable blowing zones 26.1 to 26.5 having blowing device 23 is for a fibrous web 2 with a width B in the range of 2,000 to 6,000 mm, preferably from 3,000 to 6,000 mm, in particular from 4,500 to 6,000 mm, and a maximum production speed v (arrow) of up to 600 m / min designed. Both the air volume throughput V (arrow) and the air pressure p in the individual independent blowing zones 26.1 to 26.5 can be controlled by suitable devices 42 known to the person skilled in the art and thus merely indicated.

The plant 1 shown in Figures 1 to 5 is particularly suitable for producing a long fiber paper or wet nonwoven web. The respective web may have a basis weight range of 40 to 200 g / m ² , respective fiber lengths in the range of 6 to 40 mm, preferably 8 to 30 mm, in particular 10 to 25 mm, and a binder content of 10 to 30%.

In summary, it can be stated that the invention provides an improved suction device of the type mentioned in the introduction, which avoids the disadvantages of the prior art as far as possible, preferably entirely. In particular, the transfer of the wet and still unglued fibrous web from the Bindersiebpartie is designed to process more reliable in the drying unit so that it does not adversely affect the runnability of the system and does not represent a barrier to a future increase in production speeds.

LIST OF REFERENCE NUMBERS

1 plant

2 fibrous web

3 pulp suspension unit

4 railroaders

5 inclined screen

6 headbox

7 Bindersiebpartie

8 binder sieve

9 Binder casserole

10 drying unit

11 dryer sieve

12 rewinders

13 winding core

14 winding roll

15 containers ("pulpers")

16 agitator

17 containers ("pulpers")

18 agitator

19 pump

20 pump

21 arrow

22 continuous furnace

23 blowing device

24 air

25 medium

26.1 to 26.5 blowing zone

27 positioning device

28 pivoting device

29 swivel cylinder 30 housing

31 blower (arrow)

32 suspended cushions

33 boundary wall

34 Outer wall surface

35 guide surface

36 outlet opening

37 inlet side area

38 air duct

39 outlet side area

40 air duct

41 cover plate

42 establishment

A working position a distance

B width (arrow)

H horizontal h horizontal

L direction (arrow)

M center plane

P air pressure

R rest position

R1 series

R2 series

S adjustment range

V air flow rate (arrow)

V production speed (arrow)

X Detail view

Y view α angle

Claims

Plant for producing a fibrous web Patent claims

Plant (1) for producing a fibrous web (2), in particular a long fiber paper or wet nonwoven web, comprising a pulp suspension unit (3) for producing an aqueous suspension of all components, a web former (4) for dewatering the aqueous suspension and forming the fibrous web (2) having an oblique wire (5) extending at least in sections at an angle to the horizontal (H) and at least one, preferably multi-layer headbox (6), a binder wire section (7) for applying an aqueous binder to the fibrous web (2 ) comprising at least partially horizontally or approximately horizontally extending binder wire (8) and at least one binder casserole (9), a dryer wire (11) having drying unit (10) for drying and solidification of the fibrous web (2) and a rewinder (12) for continuous winding of the fibrous web (2) on the winding core e (13) to winding rollers (14), characterized in that between the Bindersiebpartie (7) and the drying unit (10) at least one preferably engagable blowing device (23) for non-contact floating control of the fibrous web (2) by means of air (24) or another flowable medium (25) is provided which has transversely to the running direction (L) of the fibrous web (2) a plurality of independently controllable blowing zones (26.1 to 26.5).

2. Plant (1) according to claim 1, characterized in that the Blaseinhchtung (23) at least over the width (B) of the fibrous web (2) extending housing (30), which at least one preferably controllable / controllable fan (31)

Generation of a floating cushion (32) is connected and which one

Boundary wall (33) whose outer wall surface (34) as

Guide surface (25) for the fibrous web (2) is preferably curved and a plurality of outlet openings (36) for the air (24) or the other flowable medium (25).

3. Plant (1) according to claim 2, characterized in that the outlet openings (36) for the air (24) or the other flowable medium (25) in at least one transverse to the running direction (L) of the fibrous web (2) extending row ( R1, R2) are arranged.

4. Plant (1) according to claim 2 or 3, characterized in that the outlet openings (36) for the air (24) or the other fluid medium (25) in two transversely to the direction (L) of the fibrous web (2) extending rows (R1, R2) are arranged, wherein the first row (R1) at outlet openings (36) in a in the inlet side region (37) of the housing (30) arranged air duct (38) and the second row

(R2) is provided at outlet openings (36) in an outlet channel (39) of the housing (30) arranged air channel (40) and wherein the in the two air channels (38, 40) provided for opening openings (36) to the center plane (M ) of the housing (30) are directed towards.

5. Plant (1) according to claim 2, 3 or 4, characterized in that in the inlet side region (37) of the housing (30) and / or in the outlet side region (39) of the housing (30) a cover plate (41) is arranged which extends from the housing (30) in the direction of the fibrous web (2) and at a distance (a) between 5 and 30 mm, preferably between 10 and 25 mm, from the fibrous web (2) and terminates substantially over the entire width (B) of the

Fiber web (2) is enough.

6. Plant (1) according to claim 5, characterized in that the cover plate (41) is fixed to the housing (30).

7. Plant (1) according to claim 5 or 6, characterized in that the cover plate (41) is adjustably mounted in the direction of the fibrous web (2).

8. Plant (1) according to one of the preceding claims, characterized in that the blowing device (23) in its working position (A) a pitch (S) relative to the horizontal (h) of +50 to -80 mm, preferably +30 to -50 mm, in particular from +20 to -30 mm.

9. Plant (1) according to one of the preceding claims, characterized in that in that the blowing device (23) having a plurality of independently controllable blowing zones (26.1 to 26.5) has an air volume throughput (V) in the range from 20 to 300 m ³ / min ^" , preferably from 30 to 250 m ³ / min ^" m, in particular from 50 to 200 m ³ / min ^» m.

10. Plant (1) according to one of the preceding claims, characterized in that the plurality of independently controllable and controllable blowing zones (26.1 to 26.5) having blowing device (23) an air pressure (p) in

Range of 0.02 to 3.0 bar, preferably from 0.05 to 2 bar.

11. Plant (1) according to one of the preceding claims, characterized in that the blowing device (23) between the working position (A) and a

Rest position (R) by means of at least one positioning device (27) positionable, in particular by means of at least one pivoting device (28) is pivotally mounted.

12. Plant (1) according to one of the preceding claims, characterized in that it for a fibrous web (2) having a width (B) in the range of 2,000 to 6,000 mm, preferably from 3,000 to 6,000 mm, in particular from 4,500 to 6,000 mm , and designed for a maximum production speed (v) of up to 600 m / min.