JPH11217786A - Prevention of contamination of canvas in papermaking machine and dry part of papermaking machine therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for preventing contamination of canvas in a papermaking machine, capable of surely and efficiently preventing stain of canvas by relatively simple means and method and satisfying durability in the papermaking machine. SOLUTION: This method for preventing contamination of canvas comprises applying a contamination-preventing chemical to outer rolls 13a9 and 13b9 located on the outside of a canvas closed loop among plural canvas rolls 13 and then, transferring the contamination-preventing chemical applied to the outer rolls 13a9 and 13b9 to a canvas 11 in a dry part of a papermaking machine feeding a wet paper P in contact with plural dryers 12 and the canvas between plural dryers 12 and the canvas traveling while drawing a definite closed loop through plural canvas rolls 13 and drying the paper P.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dry part having a canvas in a paper machine and a method for preventing the contamination of the canvas.

[0002]

2. Description of the Related Art In a paper machine of this type, a dryer or a canvas is contaminated by various substances, for example, coating materials, inks, pigments, various chemicals, etc. contained in paper as the number of days of use increases. Come. In particular, since the canvas is formed of woven fabric or felt, dirt easily adheres thereto, and it is difficult to remove the dirt. This soiling increases as the paper machine is operated for a long time, and causes deterioration of product quality and drying efficiency. That is, in a paper machine, prevention of canvas contamination is a very important technique in terms of maintaining and improving product quality.

[0003]

Therefore, there is a long-awaited need for a canvas which is hardly soiled and easily falls off in a paper machine. For example, a method of performing an antifouling treatment on the canvas itself has been developed. However, this method has a problem in durability because the canvas is heated by contact with the dryer, and is not always satisfactory.

[0004] Canvas contamination includes materials, heat conditions, pressure,
Due to many factors, such as time, it is not always easy to develop durable pollution control measures. In particular, in recent years, since strong synthetic fibers are frequently used as a material for a canvas, the life of the canvas itself is prolonged, and the accumulation and accumulation of contaminants tend to progress. In addition, due to a decrease in the quality of raw wood and an increase in the use of waste paper in the context of recycling, contaminants are often included in the raw materials. For this reason, there is an increasing need to prevent canvas contamination.

In view of the above technical background, the present invention provides a method for reliably and efficiently preventing the contamination of a canvas in a paper machine by a relatively simple means and method, and also having a durable method for preventing a canvas contamination of a paper machine. And a dry part of a paper machine therefor.

[0006]

Means for Solving the Problems The present inventors have conducted intensive studies on such problems, and as a result,
The inventor has found that the contamination is prevented by indirectly applying a chemical solution for preventing contamination to the canvas, and the present invention has been completed based on this finding.

That is, the present invention provides (1) a dry part of a paper machine that dries a wet paper web between a plurality of dryers and a canvas running in a fixed closed loop via a plurality of canvas rolls. In the above method, a pollution control chemical is applied to an outer roll located outside the closed loop of the plurality of canvas rolls, and then the pollution control chemical applied to the outer roll is transferred to the canvas.

[0008] (2) The application of the contamination preventing chemical solution
The present invention resides in the method of (1) for preventing contamination of a canvas performed on an outer roll arranged in a retracted state.

[0009] Further, (3) the method for preventing contamination of a canvas according to the above (1), wherein the application of the contamination prevention chemical solution is performed by spraying the contamination prevention chemical solution from both ends of the canvas toward the center.

(4) The method for preventing contamination of a canvas according to the above (1), wherein the application of the contamination prevention chemical solution is performed by spraying the contamination prevention chemical solution from a narrow space separated by a canvas over the entire width of the outer roll. Exist.

(5) In a dry part of a paper machine, a wet paper web is placed between a plurality of dryers and a canvas running in a fixed closed loop through a plurality of canvas rolls and dried. Of the plurality of canvas rolls, the outer roll positioned outside the closed loop of the canvas and placed in the retracted state is spray-coated with the anti-contamination chemical solution from both ends of the canvas toward the center, and then the spray applied to the outer roll. The present invention resides in a method for preventing contamination of a canvas by transferring an inhibitor chemical to a canvas.

(6) A canvas which travels in a fixed loop through a plurality of dryers and a plurality of canvas rolls is provided, and a predetermined track is formed while a wet paper web is in contact with the dryer and the canvas rolls. In a dry part which is fed along a dry part, the present invention resides in a dry part of a paper machine provided with a chemical solution spraying device for applying a chemical solution for preventing contamination to an outer roll located outside a canvas closed loop among a plurality of canvas rolls.

Further, (7) the chemical liquid ejecting apparatus is provided in the dry part of the paper machine of (6) provided for the outer roll arranged in the retracted state.

Further, (8) the chemical liquid ejecting apparatus is provided in the dry part of the paper machine according to the above (6), wherein chemical liquid ejecting nozzles are arranged near both ends of an outer roll to which a chemical liquid is to be applied.

Further, (9) the chemical liquid spray nozzle is in the dry part of the paper machine of (8), which is disposed at an angle of 3 to 6 degrees with respect to the wet paper surface.

Further, (10) the chemical liquid spray nozzle is in the dry part of the paper machine of (8), which is a straight spray nozzle.

Further, (11) the chemical liquid spray nozzle is in the dry part of the paper machine of (8), which is provided so as to follow the movement of the outer roll.

(12) In the chemical liquid ejecting apparatus, a long chemical liquid ejecting nozzle unit having a plurality of nozzles over the entire width of an outer roll to which a chemical liquid is to be applied is provided in a narrow space separated by a canvas. And in the dry part of the paper machine described in (6) above.

Further, (13) there is provided a canvas which travels in a fixed closed loop through a plurality of dryers and a plurality of canvas rolls, and a predetermined track is formed while a wet paper web is in contact with the dryer and the canvas rolls. In the dry part to be fed along, the outer roll positioned outside the closed loop of the plurality of canvas rolls and arranged in the retracted state, and the wet roll surface near both ends of the outer roll. The present invention resides in a dry part of a paper machine provided with a chemical solution spray nozzle for applying a pollution control chemical solution arranged at an angle of 3 to 6 degrees.

According to the present invention, a chemical solution is applied to a canvas roll located outside the canvas closed loop among a plurality of canvas rolls. That is, the chemical is applied to the so-called outer roll of the canvas roll, whereby the chemical is transferred from the outer roll to the outer surface of the canvas,
As a result, the drug solution is uniformly applied to the canvas. The wet paper fed in the paper machine is sent along a predetermined track while being in contact with the outer surface of the canvas, that is, the surface to which the chemical is applied. A strong peeling film is formed on the surface of the canvas that comes into contact with the wet paper, so that it is possible to effectively prevent contaminants and the like from adhering to the canvas from the wet paper.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a dry part of a paper machine according to the present invention will be described below with reference to the drawings. FIG. 1 shows a dry part in a paper machine according to this embodiment. The dry part in this example is the first group 1
There are three groups: a dry part of zero, a dry part of the second group 20, and a dry part of the third group 30.

For example, in the dry part of the first group 10, the upper and lower canvases 11 run in a fixed closed loop via a plurality of canvas rolls 13, respectively. Wet paper is attached between the plurality of arranged dryers and the endless canvas and sent at the same speed as the canvas. Dry part of second group 20 and third group 3
The dry part of 0 has substantially the same configuration.

In the case of the dry part of the first group 10, the dryers 12a1, 12a2, 12a3 and the inner canvas rolls 13a1, 13a2,. . . , 13a8 and an outer roll 13a9, which are arranged in a row in a fixed arrangement as shown in the illustrated example. The upper canvas 11a
The vehicle travels sequentially between the plurality of dryers 12 arranged in this manner. As is clear from the figure, the inner canvas rolls 13a1 to 13a8 are arranged inside the canvas 11a, and the outer roll 13a9 is arranged outside.

As described above, in the dry part, there is at least one outer roll 13a9 for adjusting the tension of the canvas 11a.
Although not shown, the tension can be adjusted by making the inner canvas roll 13a6 movable.

In the dry part of the first group 10,
The dryers 12b1, 12b2, 12b3 and the inner canvas rolls 13b1, 13b2,. . . , 13b8 and the outer roll 13b9, and the lower canvas 11b
Travels sequentially between the dryers 12 and the like arranged in this manner. As in the case of the upper canvas 11a,
Inner canvas rolls 13b1 to 13b8 are canvas 1
1b, and the outer roll 13b9 is disposed outside.

The wet paper P is fed along a predetermined track while alternately abutting each of the upper canvases 11a and dryers 12a and the lower canvases 11b and dryers 12b. Wet paper P is dryer 12a or dryer 1.
By contact traveling with 2b (from left to right in the figure), it is gradually dried.

In the dry part of the second group 20, the upper and lower canvases 21a, 21b run in a fixed closed loop via a plurality of canvas rolls 23a, 23b, respectively. A plurality of dryers 22a and 22b arranged in a row
Between the endless canvases 21a and 21b
Are sent at the same speed. Regarding the specific arrangement relationship of the dryers 22a and 22b and the canvas rolls 23a and 23b in the dry part of the second group 20, the first part
Although slightly different from the case of the group 10, the substantial configuration of both is the same.

That is, the wet paper P is placed on each of the upper canvases 2.
1a and each dryer 22a and each lower canvas 21b
The sheet is fed along a predetermined track while alternately contacting each dryer 22b. While passing through the dry part of the first group 10 and the dry part of the second group 20, the wet paper P is pressed against the dryer surface by a canvas and is gradually dried. It should be noted that a fourth group of dry parts and a next dry part may be provided as necessary.

The apparatus of the present invention is provided with a chemical spraying device for supplying a pollution control chemical to a predetermined canvas roll for setting a travel route of the canvas. In this embodiment, for example, in the dry part of the first group 10, the chemical liquid ejecting apparatus is arranged on the upper outer roll 13a9 or the lower outer roll 13b9.

FIG. 2 shows an example of the overall configuration of the chemical liquid ejecting apparatus. This chemical liquid ejecting apparatus has an outer roll 13a9.
Alternatively, a mixer for mixing a suitable amount of fresh water sent from the flow meter 2 with the chemical solution in the chemical solution tank 3 and feeding the mixture to the chemical solution injection nozzle 1 with a pair of chemical solution injection nozzles 1 arranged near both ends of the outer roll 13b9 And 4. The chemical spray nozzle 1 is preferably a straight spray nozzle.

The chemical solution used here can be easily transferred (ie, transferred) from the canvas roll to the canvas, as described later, and once applied to the canvas, it has a pollution preventing function. Things are adopted. In addition, as a result, since this chemical adheres slightly to paper, it is preferable that the chemical does not adversely affect the quality even if it is contained in paper. As a chemical satisfying such conditions, a silicone oil is preferable. Specifically, it is used as an emulsion obtained by emulsifying a silicone oil with an activator. Here, as silicone oil,
For example, methylphenyl silicone oil, diethyl silicone oil, amino-modified silicone oil, epoxy-modified silicone oil, higher fatty acid-modified silicone oil and the like are employed.

FIG. 3 shows a state in which the chemical is injected from the chemical injection nozzle 1 to the outer roll 13a9 or the outer roll 13b9. By the way, the canvas forms a closed loop, and in order to adjust the tension, at least one outer roll located outside the canvas closed loop is provided among a plurality of canvas rolls. This outer roll has a retracted structure, and one canvas roll arranged upstream or downstream thereof (for example, in the dry part of the first group 10 in FIG. 1, the canvas roll 13a6 is replaced with the outer roll 13a9).
(Which is arranged downstream of the outer roll) or the outer roll itself can be adjusted to adjust the tension of the canvas closed loop.

The chemical liquid ejecting apparatus of the present invention, that is, the chemical liquid ejecting nozzle 1 is provided so as to spray and apply the chemical liquid to the outer roll disposed in the retracted structure. From the viewpoint of injection efficiency, each chemical liquid injection nozzle 1 is preferably installed at a distance of, for example, about 3 to 7 cm from both ends of the outer roll 13a9 or the outer roll 13b9. Similarly, from the viewpoint of injection efficiency, each chemical liquid injection nozzle 1 has an angle of 3 ° to 8 ° with respect to the longitudinal axis direction.
It is preferable to be installed at an angle of about °. Since the disposition position and the inclination angle of the chemical liquid ejecting nozzle 1 can be freely adjusted as appropriate, it is of course possible to make adjustments in a range other than the above. The length of the outer roll 13a9 (13b9) has a shaft length that can be adapted to the paper width (for example, about 5 to 10 m).

The rotating outer roll 13a9 (13b
9), the chemical is injected from the chemical injection nozzle 1 substantially to the vicinity of the center as shown. The chemical liquid is uniformly applied to the outer roll 13a9 (13b9) surface by this chemical liquid injection. In this way, the chemical solution is uniformly applied, so that in the next stage, the outer roll 13a9
On the outer surface of the canvas 11a (11b) in contact with (13b9), a film that does not attract contamination, that is, a film having strong peeling property is formed.

The present invention is not a method of directly spraying a chemical solution on the canvas 11a (11b), that is, the first method.
As a step, first, the outer roll 13a9 (13b9)
The second step is a method of spraying a chemical solution onto the canvas 11a and transferring (transferring) the applied chemical solution to the canvas 11a (11b). By utilizing this indirect transition (translocation) action, the canvas 11a (11
b) There is an advantage that the chemical solution is uniformly applied to the surface, but this point is extremely characteristic.

Further, since a chemical is spray-coated on the outer roll disposed in the retracted state structure,
The injection target space is partitioned into a narrow space separated from the outside air by the upper and lower canvases 11a (11b). As a result, the chemical solution is not scattered, the external environment is not polluted, and the chemical solution is not scattered. By the way, as described above, there is a method in which the outer roll 13a9 (13b9) moves in the tension adjustment of the canvas 11a (11b). In this case, in order to dispose the chemical liquid ejecting nozzle 1, the chemical liquid ejecting nozzle 1 is also configured to move following the movement of the outer roll 13a9 (13b9).

For example, the outer rolls 13a9 (13b
9) The structure in which the chemical liquid injection nozzle is disposed via a bracket (not shown) attached to the rotating shaft is adopted. Also,
The chemical liquid spray nozzle 1 may be attached to an outer frame (not shown) of the dry part, and may be configured to follow the movement of the outer roll. The wet paper web P travels along a predetermined track while being in contact with the outer surface of the canvas 11a (11b). As described above, the contaminants and the like from the wet paper P do not adhere to the canvas 11a (11b) having the chemical liquid film and are easily peeled off even if they are temporarily attached, thus effectively contaminating the canvas 11a (11b). Can be prevented.

FIG. 4 shows a modification of the chemical liquid ejecting apparatus. In this example, there is provided a long chemical liquid spray nozzle unit 1 'which is horizontally extended at a predetermined interval in parallel with the outer roll 13a9 or the outer roll 13b9. The chemical spray nozzle unit 1 'has at least the width of the outer roll 13a9 (13b9) and is provided with a plurality of chemical spray nozzles. The chemical liquid is fed from the mixer 4 to the chemical liquid injection nozzle unit 1 '.

In the example shown in FIG. 4, as shown in FIG.
A spray-type chemical is uniformly jetted over the entire width of (13b9). In this case, the upper and lower portions of the outer rolls 13a9 (13b9) arranged in the retracted state are narrow spaces separated by a canvas, thereby preventing the chemical solution from being dissipated. Also in this case, a strong peeling film is formed on the outer surface of the canvas 11a (11b), so that it is possible to prevent contaminants and the like from adhering to the wet paper web P. In this case, in order to dispose the chemical liquid ejecting nozzle unit 1 ', the chemical liquid ejecting nozzle unit 1' also moves following the movement of the outer roll 13a9 (13b9), similarly to the chemical liquid ejecting nozzle 1 shown in FIG. It is also possible to adopt a structure in which

In the above description, an example was shown in which the apparatus of the present invention was applied to the first group 10 of the dry part.
The same applies to 0. Also in the second group 20, the chemical liquid ejecting devices are arranged for the upper and lower outer rolls, and the chemical liquid supplied thereto is supplied to the upper and lower canvases 21a and 21a, respectively.
1b.

Here, FIGS. 5 and 6 show examples of different types of dry parts. The apparatus of the present invention can be effectively applied to the outer roll 5 in the so-called serpentine run type dry part shown in FIG. 5 and the so-called unolol type dry part outer rolls 6 and 6 'shown in FIG. The same operation and effect as those of the above embodiment can be obtained. Furthermore, it is applicable to other types of dry parts.

Although the present invention has been described above, the present invention is not limited to the embodiment, and it goes without saying that various other modifications are possible without departing from the essence of the present invention. For example, the arrangement position of the chemical liquid ejecting nozzle 1 and the numerical value of the inclination angle are not limited to the above embodiment, and can be appropriately selected. Further, those having a large number of outer rolls are applicable to them.

[0043]

As described above, according to the present invention, in a paper machine of this kind, a chemical film having a strong releasability is formed on the surface of the canvas by an indirect method, so that the chemical is uniformly applied to the canvas. Is done. Therefore, it is possible to effectively prevent contaminants and the like from attaching to the canvas from the wet paper.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an example of a dry part in an embodiment of a canvas contamination prevention device for a paper machine according to the present invention.

FIG. 2 is a diagram illustrating an example of an overall configuration of a chemical liquid ejecting apparatus according to the present invention.

FIG. 3 is a view showing the operation of the chemical liquid ejecting apparatus in the embodiment of the canvas contamination preventing apparatus for a paper machine according to the present invention.

FIG. 4 is a view showing a modified example of the chemical liquid ejecting apparatus according to the present invention.

FIG. 5 is a diagram showing examples of different types of dry parts to which the present invention can be applied.

FIG. 6 is a diagram showing examples of other different types of dry parts to which the present invention can be applied.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Chemical injection nozzle 1 '... Chemical injection nozzle unit 2 ... Flow meter 3 ... Chemical tank 4 ... Mixer 5 ... Outer roll 6, 6' ... Outer roll 10 ... First group 11 ... Canvas 11a ... Canvas 11b ... Canvas 12 ... Dryers 12b1, 12b2, 12b3 ... Dryers 13 ... Canvas rolls 13a1-13a8 ... Inner canvas rolls 13b1-13b8 ... Inner canvas rolls 13a9 ... Outer rolls 13b9 ... Outer rolls 20 ... Second group 21a, 21b ... Dryers 22a, 22b … Third group P… wet paper

Continued on the front page (72) Inventor Kunio Sekiya 1-28-14 Nagasaki, Toshima-ku, Tokyo Inside Mentec Co., Ltd.

Claims (13)

[Claims] In a dry part of a paper machine, a wet paper is put between a plurality of dryers and a canvas running in a fixed closed loop through a plurality of canvas rolls to dry the paper. A method for preventing contamination of a canvas, comprising applying an anti-contamination chemical to an outer roll located outside a closed loop of the canvas, and then transferring the anti-contamination chemical applied to the outer roll to a canvas. 2. The method for preventing contamination of a canvas according to claim 1, wherein the application of the anti-contamination chemical is performed on the outer roll arranged in a retracted state. 3. The method for preventing contamination of a canvas according to claim 1, wherein the application of the contamination prevention chemical solution is performed by spraying the pollution prevention chemical solution from both ends of the canvas toward the center. 4. The method for preventing pollution of a canvas according to claim 1, wherein the application of the pollution prevention chemical solution is performed by spraying the pollution prevention chemical solution from a narrow space separated by a canvas over the entire width of the outer roll. 5. A dry part of a paper machine in which a wet paper web is abutted between a plurality of dryers and a canvas running in a fixed closed loop through a plurality of canvas rolls to dry the plurality of canvas rolls. On the outer roll positioned outside the closed loop of the canvas and placed in the retracted state, the anti-contamination chemical liquid is spray-coated from both ends of the canvas toward the center, and then the anti-contamination chemical liquid spray-coated on the outer roll is applied to the canvas. A method for preventing pollution of a canvas, characterized by shifting. 6. A canvas which travels in a predetermined closed loop through a plurality of dryers and a plurality of canvas rolls, and feeds the dryer and the canvas rolls along a predetermined track while adhering wet paper to the canvas. 5. A dry part for a machine as defined in claim 5, wherein the dry part includes a chemical spraying device for applying an anti-pollution chemical to an outer roll located outside the closed loop of the plurality of canvas rolls. 7. The dry part of a paper machine according to claim 6, wherein the chemical liquid ejecting device is provided for an outer roll arranged in a retracted state. 8. The dry part of a paper machine according to claim 6, wherein the chemical liquid ejecting apparatus has chemical liquid ejecting nozzles arranged near both ends of an outer roll to which a chemical liquid is applied. 9. The dry part of a paper machine according to claim 8, wherein the chemical liquid spray nozzle is arranged at an angle of 3 to 6 degrees with respect to the wet paper surface. 10. The dry part of a paper machine according to claim 8, wherein the chemical liquid spray nozzle is a straight spray nozzle. 11. The dry part according to claim 8, wherein the chemical liquid spray nozzle is provided so as to follow the movement of the outer roll. 12. The liquid ejecting apparatus according to claim 1, wherein a long liquid ejecting nozzle unit having a plurality of nozzles is disposed in a narrow space separated by a canvas over the entire width of an outer roll to which a liquid is to be applied. 7. The dry part of a paper machine according to claim 6, wherein: 13. A canvas which travels in a fixed closed loop via a plurality of dryers and a plurality of canvas rolls, and feeds the dryer and the canvas rolls along a predetermined orbit while adhering wet paper to the rolls. In the dry part, the outer roll positioned outside the closed loop of the plurality of canvas rolls and disposed in the retracted state is positioned between both ends of the outer roll near the both ends of the outer roll by 3 to 6 degrees with respect to the wet paper surface. A dry part of a paper machine, comprising a chemical spray nozzle for applying a pollution preventive chemical arranged at an angle.