CN209816552U

CN209816552U - Device for contactless deflection and drying of a fibrous web

Info

Publication number: CN209816552U
Application number: CN201920351251.2U
Authority: CN
Inventors: 理查德·索林; P·T·海基莱
Original assignee: Valmet Technologies Oy
Current assignee: Valmet Technologies Oy
Priority date: 2018-03-21
Filing date: 2019-03-19
Publication date: 2019-12-20
Anticipated expiration: 2029-03-19
Also published as: AT16567U1; DE202018101573U1

Abstract

The utility model relates to a device for contactless messenger's fibre web material (W) turns to and dry, include: a housing (2) around which the fibrous web (W) is guided at least partially and the outer surface of which forms a turning element (3) for turning the fibrous web (W); and drying means (4) acting on one side of the fibre web (W), characterized in that the housing (2) has at least two separate chambers (5, 6), wherein the at least two chambers (5, 6) each have a separate inlet (7, 8) for drying medium, and that a temperature of at least 200 ℃ prevails at least in the first chamber (5) acting first on the fibre web (W).

Description

Device for contactless deflection and drying of a fibrous web

Technical Field

The utility model relates to a device for contactless messenger's fiber web material turns to and dries, it has: a housing around which the fibrous web is guided at least partially and whose outer surface forms a turning element for turning the fibrous web; and a drying device acting on one side of the fibre web.

Background

A generic device is known from DE3942029B 4. In such an apparatus, it is necessary to install additional drying devices before and, in some cases, also after the apparatus, respectively, in order to achieve sufficient drying of the fibre web, since this is a prerequisite for a good quality of the coating to be carried out in the next step. These additional drying devices result in considerable outlay in terms of procurement costs and energy costs.

SUMMERY OF THE UTILITY MODEL

It is therefore an object of the present invention to provide a device for turning and drying a fiber web, which device ensures reliable drying of the fiber web in a simple manner.

According to the invention, the housing, which is at least partially surrounded by the fiber web and whose outer surface also forms the deflecting element for deflecting the fiber web, is divided into at least two chambers, so that different temperatures can be set in the two chambers. According to the invention, this will be simplified by having the two chambers with separate inlets for the drying medium.

According to the invention, by achieving a temperature of at least 200 ℃ in the first chamber, i.e. the chamber in which the drying medium acting first on the fiber web is located or through which the fiber web is first guided, a substantial increase in drying capacity is achieved, so that additional drying means can be eliminated. Thereby, not only can the dwell time of the fibre web between the coating device and the start-up drying be made shorter, but in this way also the construction of the device according to the invention is made very simple and compact.

According to a particularly preferred embodiment of the invention, the temperature prevailing in the first chamber can be made higher than the temperature prevailing in the second chamber, which acts on the fiber web after the first chamber. Hereby a stepwise drying of the fibre web is achieved, which greatly improves the efficiency of the device according to the invention.

With regard to a good drying effect of the fiber web, it has proved to be particularly advantageous: the temperature prevailing in the first chamber is 200 ℃ to 500 ℃, preferably 250 ℃ to 350 ℃, and the temperature prevailing in the second chamber is 100 ℃ to 350 ℃, preferably 100 ℃ to 200 ℃.

According to a further particularly preferred embodiment of the invention, the outlet for the drying medium in the first chamber can be connected to the inlet for the drying medium in the second chamber. In this way, a significant energy saving can be achieved, since the thermal energy of the drying medium conducted out of the first chamber can also be used for a subsequent drying process of the fiber web.

Such a connection can be realized very simply and reliably as: the outlet for the drying medium in the first chamber is connected with the inlet for the drying medium in the second chamber by means of a connecting duct.

Furthermore, in order to ensure that the drying medium achieves the desired flow, an exhaust fan may also be provided in the connecting duct.

According to the utility model discloses a high temperature in the device can realize very simply: i.e. to provide the drying device with at least one gas burner and/or at least one electric heating element and/or at least one steam heating element.

Here, it can be provided that: each of the at least two chambers is assigned a separate gas burner and/or a separate electric heating element. This enables a very precise setting of the desired temperature in the at least two chambers.

Furthermore, in order to reduce the costs of the device according to the invention, a common gas burner and/or a common electric heating element can be assigned to the two chambers.

Very high efficiencies can be achieved in connection with the drying of the fibre web when the drying medium is a gas, in particular air.

The utility model provides a device for contactless messenger's fiber web material turns to and is dry, include: a housing around which the fiber web is guided at least partially and the outer surface of which forms a diverting element for diverting the fiber web; and a drying device acting on one side of the fiber web, wherein the housing has at least two separate chambers, each having a separate inlet for a drying medium, and a temperature of at least 200 ℃ prevails at least in the first chamber acting first on the fiber web.

Preferably, the temperature prevailing in the first chamber is higher than the temperature prevailing in the second chamber, which second chamber acts on the fibre web after the first chamber.

Preferably, the temperature prevailing in the first chamber is between 200 ℃ and 500 ℃, preferably between 250 ℃ and 350 ℃, and the temperature prevailing in the second chamber is between 100 ℃ and 350 ℃, preferably between 100 ℃ and 200 ℃.

Preferably, the outlet for the drying medium from the first chamber is connected with the inlet for the drying medium into the second chamber.

Preferably, the outlet for the drying medium from the first chamber is connected by means of a connecting duct with the inlet for the drying medium into the second chamber.

Preferably, an exhaust fan is arranged in the connecting duct.

Preferably, the drying device has at least one gas burner and/or at least one electric heating element and/or at least one steam heating element.

Preferably, a separate gas burner and/or a separate electric heating element is associated with each of the at least two chambers.

Preferably, a common gas burner and/or a common electric heating element is associated with at least two chambers.

Drawings

Embodiments of the present invention will be described in principle with reference to the accompanying drawings. Wherein:

fig. 1 shows a first embodiment of a device according to the invention;

fig. 2 shows a second embodiment of the device according to the invention;

fig. 3 shows a third embodiment of the device according to the invention;

fig. 4 shows a fourth embodiment of the device according to the invention;

fig. 5 shows a fifth embodiment of the device according to the invention.

Detailed Description

Fig. 1-5 show various embodiments of an arrangement 1 for turning and drying a fibre web W, in particular a paper or board web. The running direction of the fibrous web W through the device 1 is schematically indicated in fig. 1 to 5 by means of an arrow on the end of the fibrous web W, respectively.

The device 1 has a housing 2 around which the fibrous web W is guided at least partly. The outer surface of the shell 2 thus forms a diverting element 3 for diverting the fibrous web W. In the present case, "turning" refers to a change of direction of the fibrous web W from a vertically upward direction to a vertically downward direction. Obviously, the turning element 3 may also be configured such that it causes another change of direction of the fibrous web W, for example, a change of direction at an angle different from 180 °. The device 1 furthermore has a drying device 4 which acts on the part of the fibre web W running around the housing 2 and thus effects one-sided drying of the fibre web W. The drying device 4 has an air supply device 4a which supplies a drying medium, preferably heated air, to the interior of the housing 2. The air supplied to the interior of the housing 2 is then discharged outwardly in the direction of the fibre web W through openings, not shown, in the surface or curved wall of the housing 2. The fibre web W is thus moved on an air cushion around the housing 2 and is deflected and dried contactlessly by the air cushion.

The housing 2 has at least two separate chambers 5 and 6, which are connected to an air supply 4a, so that air or generally a drying medium can be introduced into the corresponding chambers of the housing 2 and, if necessary, be discharged therefrom. In all the embodiments of the invention described herein, the housing 2 has exactly two chambers 5 and 6, but in principle a larger number of chambers can be used. Hereby, the chamber through which the fibrous web W is first guided is referred to as first chamber 5 in the following, and the chamber through which the fibrous web W is guided after the first chamber 5 is referred to as second chamber 6. That is, the drying medium flowing out of the first chamber 5 is in contact with the fibrous web W before the drying medium flowing out of the second chamber 6.

The two chambers 5 and 6 each have a separate inlet for a drying medium, not shown, such as air, used by the drying device 4. The inlet of the first chamber 5 is denoted by reference numeral 7 and the inlet of the second chamber 6 by reference numeral 8.

In this case, a temperature of at least 200 ℃ prevails in the first chamber 5. It is particularly preferred that the temperature in the first chamber 5 is higher than the temperature in the second chamber 6. It has proved to be particularly advantageous for effective drying of the fibre web W: there is a temperature of 200 ℃ to 500 ℃, preferably 250 ℃ to 350 ℃, in the first chamber 5 and a temperature of 100 ℃ to 350 ℃, preferably 100 ℃ to 200 ℃, in the second chamber 6. It can be seen that: the two temperature ranges in the two chambers 5 and 6 are partly coincident. However, the above statements apply to the following temperature ranges: hereby, the temperature prevailing in the first chamber 5 is preferably higher than the temperature prevailing in the second chamber 6.

The various embodiments according to fig. 1 to 5 differ mainly in the design of the drying means 4, in particular the air supply means 4 a. Different embodiments of the drying device 4 or the air supply device 4a will be described in detail below. In all embodiments, the drying device 4 or the air supply device 4a may comprise a gas burner 9 and/or an electrical heating element, not shown. Therefore, all the description for the gas burner 9 also includes the use of an electric heating element.

In the embodiment of the device 1 shown in fig. 1, two chambers 5 and 6 are each assigned a separate gas burner 9. Here, the drying device 4 or the air supply device 4a is in principle identical for each of the two chambers 5 and 6. The gas burner 9 introduces the drying medium into the respective chamber 5 or 6 through a duct 10 leading to the inlet 7 or 8. Each gas burner 9 is connected with a gas supply duct 11, a combustion air blower 12 and a circulating air blower 13.

During the supply of the combustion air blower 12 by means of the preheater or heat exchanger 14, the circulating air blower 13 draws air out of the respective chamber 5 or 6 through the outlet 15 in order to supply it to the gas burner 9 and heat it accordingly, before being reintroduced into the respective chamber 5 or 6. A combustion air line 16 and an air supply line 17 each lead to the heat exchanger 14. Further, an exhaust fan 18 and a muffler 19 are connected to the heat exchanger 14.

That is to say, in the embodiment shown in fig. 1, the two chambers 5 and 6 are heated completely independently of one another, wherein the gas burner 9 is supplied with fresh air and with air taken from the respective chamber 5 or 6.

In the embodiment of the device 1 shown in fig. 2, two gas burners 9 are likewise provided, which are connected to the inlets 7 or 8 of the chambers 5 or 6 by means of corresponding conduits 10. That is, a separate gas burner 9 is provided for each chamber 5 or 6. The two chambers 5, 6 are also provided with a gas supply duct 11 leading to the gas burner 9, a combustion air blower 12 and a circulating air blower 13. However, unlike the embodiment shown in fig. 1: the outlet 15 for the drying medium from the first chamber 5 is connected by means of a connecting duct 20 with the inlet 8 for the drying medium into the second chamber 6. For this purpose, an additional exhaust fan 21 is provided, which is arranged in the connecting duct 20 and which draws air out of the first chamber 5 and introduces it into the second chamber 6 via the gas burner 9, the duct 10 and the inlet 8. Whereby the exhaust air from the first chamber 5 can be reused. In this way energy can be saved and there is no expected disadvantage in connection with the drying of the fibre web W, because the temperature in the second chamber 6 is indeed lower than in the first chamber 5.

As in the embodiment according to fig. 1, the heat exchanger 14 is provided with an exhaust gas fan 18 coupled thereto and a silencer 19 following it in the air flow direction. However, unlike the embodiment shown in fig. 1: this heat exchanger 14 supplies both chambers 5 and 6, i.e. only one heat exchanger 14 is provided.

The embodiment shown in fig. 3 differs from the embodiment shown in fig. 2 in that: only the first chamber 5 is provided with a gas burner 9, while the second chamber 6 is provided with drying medium only by the exhaust air from the first chamber 5. The heat exchanger 14 can thus be realized simply and the combustion air blower 12 is eliminated in addition to the second gas burner 9. Similarly to what is shown in fig. 2, there is also provided an exhaust fan 21 which is arranged in a connecting duct 20 connecting the two chambers 5 and 6 to one another, draws the drying medium out of the first chamber 5 and supplies it to the second chamber 6 via an inlet 8 by means of a circulating air blower 13 also arranged there.

The embodiment of the device 1 shown in fig. 4 is very similar to the embodiment shown in fig. 3, i.e. here too, only a gas burner 9 is provided, i.e. a gas burner for the first chamber 5. That is, the second chamber 6 is also supplied with drying medium only by the exhaust air from the first chamber 5. In contrast to the embodiment shown in fig. 3, a part of the drying medium or air is supplied to the second chamber 6 via a heat exchanger 14, similar to the embodiment shown in fig. 2. The heat exchanger 14 is therefore in principle identical to the heat exchanger according to the embodiment shown in fig. 2. However, in contrast to the embodiment shown in fig. 2, the combustion air blower 12 is not present at all in the embodiment shown in fig. 4, but rather a circulating air blower 13 is connected to a heat exchanger 14.

In the embodiment shown in fig. 5, the gas burner 9 is provided only for the first chamber 5, i.e. the second chamber 6 is here also provided with drying medium only by the exhaust air from the first chamber 5. In addition, the drying medium is removed from the first chamber 5 via the outlet 15 by means of an exhaust fan 21 and fed to the second chamber 6 via the inlet 8. However, no return of the drying medium from the second chamber 6 to the second chamber 6 is provided, as in the embodiment shown in fig. 1 to 4, i.e. the drying medium is directed from the outlet 15 of the second chamber 6 to the heat exchanger 14.

Claims

1. An apparatus for contactlessly turning and drying a fibrous web, comprising: a housing (2) around which the fibrous web (W) is guided at least partially and the outer surface of which forms a turning element (3) for turning the fibrous web (W); and drying means (4) acting on one side of the fibre web (W), characterised in that the housing (2) has at least two separate chambers (5, 6), wherein the at least two chambers (5, 6) each have a separate inlet (7, 8) for drying medium, and wherein a temperature of at least 200 ℃ prevails at least in the first chamber (5) acting first on the fibre web (W).

2. An arrangement according to claim 1, characterized in that the temperature prevailing in a first chamber (5) is higher than the temperature prevailing in a second chamber (6) acting on the fibrous web (W) after the first chamber (5).

3. The device according to claim 2, characterized in that the temperature prevailing in the first chamber (5) is 200 ℃ to 500 ℃ and the temperature prevailing in the second chamber (6) is 100 ℃ to 350 ℃.

4. Device according to claim 2, characterized in that the outlet (15) for drying medium from the first chamber (5) is connected with the inlet (7) for drying medium into the second chamber (6).

5. A device according to claim 3, characterized in that the outlet (15) for drying medium from the first chamber (5) is connected with the inlet (7) for drying medium into the second chamber (6).

6. Device according to claim 4, characterized in that the outlet (15) for drying medium from the first chamber (5) is connected by means of a connecting duct (20) with the inlet (7) for drying medium into the second chamber (6).

7. The device according to claim 6, characterized in that an exhaust fan (21) is arranged in the connecting duct (20).

8. The device according to any one of claims 1 to 7, characterized in that the drying device (4) has at least one gas burner (9) and/or at least one electric heating element and/or at least one steam heating element.

9. Device according to claim 8, characterized in that a separate gas burner (9) and/or a separate electric heating element is assigned to each of the at least two chambers (5, 6).

10. Device according to claim 9, characterized in that a common gas burner (9) and/or a common electric heating element is assigned to the at least two chambers (5, 6).

11. The device according to any one of claims 1 to 7, wherein the drying medium is a gas.