EP0989231A2 - Controlling the moisture profile - Google Patents

Controlling the moisture profile Download PDF

Info

Publication number
EP0989231A2
EP0989231A2 EP99112923A EP99112923A EP0989231A2 EP 0989231 A2 EP0989231 A2 EP 0989231A2 EP 99112923 A EP99112923 A EP 99112923A EP 99112923 A EP99112923 A EP 99112923A EP 0989231 A2 EP0989231 A2 EP 0989231A2
Authority
EP
European Patent Office
Prior art keywords
web
fibrous web
cylinder
electromagnetic waves
electrodes
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP99112923A
Other languages
German (de)
French (fr)
Other versions
EP0989231A3 (en
Inventor
Robert Wolf
Markus Oechsle
Wolfgang Mayer
Roland Mayer
Frank Wegehaupt
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Voith Patent GmbH
Original Assignee
Voith Paper Patent GmbH
Voith Sulzer Papiertechnik Patent GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Voith Paper Patent GmbH, Voith Sulzer Papiertechnik Patent GmbH filed Critical Voith Paper Patent GmbH
Publication of EP0989231A2 publication Critical patent/EP0989231A2/en
Publication of EP0989231A3 publication Critical patent/EP0989231A3/en
Withdrawn legal-status Critical Current

Links

Images

Classifications

    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21F—PAPER-MAKING MACHINES; METHODS OF PRODUCING PAPER THEREON
    • D21F5/00—Dryer section of machines for making continuous webs of paper
    • D21F5/16—Drying webs by electrical heating
    • D21F5/167—Microwave heating
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F26—DRYING
    • F26B—DRYING SOLID MATERIALS OR OBJECTS BY REMOVING LIQUID THEREFROM
    • F26B13/00—Machines and apparatus for drying fabrics, fibres, yarns, or other materials in long lengths, with progressive movement
    • F26B13/10—Arrangements for feeding, heating or supporting materials; Controlling movement, tension or position of materials
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F26—DRYING
    • F26B—DRYING SOLID MATERIALS OR OBJECTS BY REMOVING LIQUID THEREFROM
    • F26B3/00—Drying solid materials or objects by processes involving the application of heat
    • F26B3/32—Drying solid materials or objects by processes involving the application of heat by development of heat within the materials or objects to be dried, e.g. by fermentation or other microbiological action
    • F26B3/34—Drying solid materials or objects by processes involving the application of heat by development of heat within the materials or objects to be dried, e.g. by fermentation or other microbiological action by using electrical effects
    • F26B3/347—Electromagnetic heating, e.g. induction heating or heating using microwave energy

Definitions

  • the invention relates to a method and the associated devices for Moisture profiling of a fibrous web to be dried, in particular a paper, Cardboard or tissue web in machines for the production and / or finishing of the same.
  • the fibrous webs are currently used for drying over heated cylinders guided. This complex process often results in an uneven distribution of the Moisture across the fibrous web. To correct this moisture cross profile certain zones additionally humidified or heated, the heating in the generally done inductively or by means of IR radiators and humidification with steam.
  • the object of the invention is therefore a method that is as simple and precise as possible and to develop at least one corresponding device for moisture profiling.
  • the object was achieved in that the fibrous web electromagnetic waves in the form of microwaves and / or high frequency waves is exposed. This is essentially due to the fact that the fibrous web is on at least one microwave transmitter and / or at least two with one High-frequency source connected electrodes of different polarity passed becomes.
  • the high-frequency range lies approximately in the range between 10 and 300 MHz and the Microwave range between 300 MHz and 30 GHz. To ensure a uniform effect on the fibrous web, the Field energy of the electromagnetic waves across the fibrous web should also be possible be evenly distributed.
  • the method is used in the areas where the fibrous web unites Has a dry content between 60 and 95%. On the one hand, these areas do not have to too much water to be heated and on the other hand is sufficient moisture to Absorption of the electromagnetic waves is present.
  • the fibrous web is also supported in the area of electromagnetic waves. This stabilizes the Run of the fibrous web and reduces the risk of tearing. For this, the The fibrous web is guided over a rotating cylinder.
  • the drying of the fibrous web at least predominantly by electromagnetic waves occur. Most of the time, however, the drying on conventional way, i.e. for example via heated cylinders, so that electromagnetic waves essentially only to compensate for Differences in moisture serve across the fibrous web.
  • One or more waveguides are preferably used as the microwave transmitter Application, which are each connected to at least one microwave source and at least transversely to the fibrous web as evenly distributed as possible should. The result is a relatively even distribution of field energy Microwaves across the fibrous web.
  • the fibrous web should have a microwaves rotating cylinder.
  • the jacket of the cylinder or an outer coating of this jacket consist of a material that the Microwaves absorbed worse than the fibrous web. This is suitable for example Teflon.
  • the thickness of the coating should be between 5 and 150 mm, are preferably between 10 and 50 mm.
  • the course of the fibrous web can also be used alone or in addition to at least one sieve is supported, the material of which the microwaves are worse than the fibrous web absorbs.
  • the electrodes should be in the form of Stick electrodes, capacitor plates and / or rotating cylinders.
  • the fibrous web should rotate in the region of the electrodes Cylinder guided and preferably supported by a sieve.
  • the preferably predominantly metallic Cylinder forms an electrode and on the with respect to the fibrous web opposite side at least one stick electrode and / or one Capacitor plate of different polarity is arranged. It is included as a protective measure an advantage if the cylinder has an electrically insulating outer coating. On the other hand, it is also possible that in the wrapping area of the cylinder there are at least two stick electrodes of different polarity, the High-frequency waves partially penetrate the fibrous web.
  • FIG. 1 there is a microwave transmitter 2 along the looping area arranged outside the cylinder 3.
  • the microwave transmitter 2 consists of a series of several across Path running waveguides with a rectangular cross-section, each with are connected to a microwave source. However, it is also possible that Arrange waveguide meandering. The resulting microwaves provide for the fact that the wetter parts of the fibrous web 1 are heated up more and thus are dried than the other areas. The result is a more even one Moisture cross profile.
  • a shield 6 is arranged around the microwave transmitter 2, so that none Microwaves leave this device.
  • the cylinder 3 is approximately 2 cm thick Coating 4 made of Teflon, which absorbs the microwaves less strongly than that Fibrous web 1. The thickness of the coating 4 ensures that the metallic Area of the cylinder 3 is as far away from the fibrous web 1, so that a the greatest possible field strength of the microwaves in the fibrous web 1 is guaranteed.
  • Figures 2 and 3 show high frequency devices in which the run of the Fibrous web 1 is stabilized via a running, external sieve 5.
  • the devices with a shield 6 for Provide high frequency waves.
  • the fibrous web 1 is connected to a high-frequency source (HF) Electrodes of different polarity passed. This also leads to warming and drying the moist areas of the fibrous web 1 with the result a relatively uniform moisture cross profile.
  • HF high-frequency source
  • the metallic, rotating cylinder 3 itself forms one with the high-frequency source connected electrode 7.
  • the electrode 7 of the other polarity is of a Capacitor plate formed, which is arranged in the wrapping area of the cylinder 3 is.
  • the high-frequency waves penetrate the fibrous web 1, which the Arrangement makes it very effective. Because of the function of the cylinder 3 as an electrode 7 it should have an electrically insulating coating in the moist area Own fibrous web 1.
  • all electrodes 7 are formed by stick electrodes in FIG. 3, which are arranged in the wrapping area of the cylinder 3.
  • the one High-frequency source (HF) connected electrodes are polarized so that Adjacent stick electrodes always have different polarities. That I field forming between the electrodes 7 penetrates the fibrous web 1 at least partially, which also leads to the heating and drying of the damp areas the fibrous web 1 leads.
  • HF High-frequency source
  • the stick electrodes as well as the capacitor plate extend essentially across the fibrous web 1 and parallel to the cylinder 3.
  • the devices can be in several places on a paper or coating machine be arranged. Furthermore, the entire drying process can will be realized. However, such devices are preferably for Moisture cross profile correction in dryer sections with conventionally heated Drying cylinders, which are wrapped in the fibrous web.

Abstract

To set the moisture profile of a fiber web material (1) in a papermaking or finishing machine, it is treated with electromagnetic waves as microwaves and/or high frequency (HF) waves. The field energy of the electromagnetic waves is distributed evenly across the web (1), when the web (1) has a dry content of 60-95%. The web (1) is supported in its movement path, at least at the zone subjected to electromagnetic waves. The web drying action is mainly through the exposure to electromagnetic waves, or only partially by them to compensate for differences in the moisture content across the web (1). An Independent claim is included for a web drying station, where the web (1) is moved past a microwave transmitter (2). Preferred Features: The microwave transmitter (2) has one or more hollow waveguides, each linked to a microwave source, and distributed evenly across the web (1). The web (1) moves over a rotating cylinder (3) at the microwave transmitter (2) zone. The cylinder (3) has a mantle or an outer cladding (4) of a material which absorbs microwaves less well than the web (1). The outer cylinder cladding (4) has a thickness of 5-150 mm and especially 10-50 mm. The support for the web (1), in its path from at least a fourdrinier (5), has a lower microwave absorption than the web (1). The path for the web (1) can carry it past at least two HF electrodes of different polarities. The electrodes are electrode rods, condenser plates and/or rotating cylinders. The web (1) moves round a rotating cylinder (3), preferably supported by a fourdrinier (5). The metal cylinder (3) can form an electrode, with a further rod electrode and/or condenser plate on the other side of the web (1), of a different polarity. The cylinder (3) can be cladded with an electrical insulation material. Where the web passes round the cylinder (3), at least two rod electrodes of different polarities generate HF waves which penetrate the web (1) at least partially. The assembly has an electromagnetic shrouding (6).

Description

Die Erfindung betrifft ein Verfahren sowie die dazugehörigen Vorrichtungen zur Feuchteprofilierung einer zu trocknenden Faserstoffbahn, insbesondere einer Papier-, Karton- oder Tissuebahn in Maschinen zur Herstellung und/oder Veredelung derselben.The invention relates to a method and the associated devices for Moisture profiling of a fibrous web to be dried, in particular a paper, Cardboard or tissue web in machines for the production and / or finishing of the same.

Gegenwärtig werden die Faserstoffbahnen zur Trocknung über beheizte Zylinder geführt. Bei diesem aufwendigen Prozeß stellt sich oft eine ungleiche Verteilung der Feuchte quer zur Faserstoffbahn ein. Zur Korrektur dieses Feuchtequerprofils werden bestimmte Zonen zusätzlich befeuchtet oder beheizt, wobei die Beheizung im allgemeinen induktiv oder mittels IR-Strahler und die Befeuchtung mit Dampf erfolgt.The fibrous webs are currently used for drying over heated cylinders guided. This complex process often results in an uneven distribution of the Moisture across the fibrous web. To correct this moisture cross profile certain zones additionally humidified or heated, the heating in the generally done inductively or by means of IR radiators and humidification with steam.

Diese Korrekturmaßnahmen sind jedoch relativ ungenau. Außerdem ist das Messen und Regeln des Feuchteprofils sehr aufwendig.However, these corrective actions are relatively imprecise. It's also measuring and regulating the moisture profile is very complex.

Die Aufgabe der Erfindung ist es daher ein möglichst einfaches und genaues Verfahren sowie zumindest eine entsprechende Vorrichtung zur Feuchteprofilierung zu entwickeln.The object of the invention is therefore a method that is as simple and precise as possible and to develop at least one corresponding device for moisture profiling.

Erfindungsgemäß wurde die Aufgabe dadurch gelöst, daß die Faserstoffbahn elektromagnetischen Wellen in Form von Mikrowellen und/oder Hochfrequenzwellen ausgesetzt wird. Dies erfolgt im wesentlichen dadurch, daß die Faserstoffbahn an zumindest einem Mikrowellen-Sender und/oder an zumindest zwei mit einer Hochfrequenz-Quelle verbundenen Elektroden unterschiedlicher Polarität vorbeigeführt wird.According to the invention the object was achieved in that the fibrous web electromagnetic waves in the form of microwaves and / or high frequency waves is exposed. This is essentially due to the fact that the fibrous web is on at least one microwave transmitter and / or at least two with one High-frequency source connected electrodes of different polarity passed becomes.

Durch den Einsatz von elektromagnetischen Wellen ergibt sich eine selbstregulierende Wirkung, da feuchtere Stellen der Faserstoffbahn stärker getrocknet werden. Dies basiert auf der Tatsache, daß Wasser diese Wellen stärker absorbiert als das trockene Papier, d.h. deren Fasern.The use of electromagnetic waves results in a self-regulating Effect, since more moist parts of the fibrous web are dried more. This is based on the fact that water absorbs these waves more than the dry one Paper, i.e. whose fibers.

Indem man hierbei das Dielektrikum Wasser einem elektrischen Feld aussetzt, kommt es zur Polarisation, also der Verschiebung von geladenen Teilchen aus der Ruhelage. Dabei entstehen Verluste, die zu einer Erwärmung des Wassers führen. Der Hochfrequenzbereich liegt etwa im Bereich zwischen 10 und 300 MHz und der Mikrowellenbereich zwischen 300 MHz und 30 GHz. Zur Gewährleistung einer gleichmäßigen Wirkung auf die Faserstoffbahn, sollte die Feldenergie der elektromagnetischen Wellen quer zur Faserstoffbahn möglichst auch gleichmäßig verteilt sein.By exposing the dielectric water to an electrical field it to polarization, i.e. the displacement of charged particles from the rest position. This results in losses that cause the water to heat up. The The high-frequency range lies approximately in the range between 10 and 300 MHz and the Microwave range between 300 MHz and 30 GHz. To ensure a uniform effect on the fibrous web, the Field energy of the electromagnetic waves across the fibrous web should also be possible be evenly distributed.

Anwendung findet das Verfahren in den Bereichen, wo die Faserstoffbahn einen Trockengehalt zwischen 60 und 95 % hat. In diesen Bereichen muß einerseits nicht zuviel Wasser erwärmt werden und ist aber andererseits ausreichend Feuchtigkeit zur Absorption der elektromagnetischen Wellen vorhanden.The method is used in the areas where the fibrous web unites Has a dry content between 60 and 95%. On the one hand, these areas do not have to too much water to be heated and on the other hand is sufficient moisture to Absorption of the electromagnetic waves is present.

Insbesondere bei hohen Geschwindigkeiten ist es von Vorteil, wenn die Faserstoffbahn auch im Bereich der elektromagnetischen Wellen gestützt verläuft. Dies stabilisiert den Lauf der Faserstoffbahn und verringert die Gefahr von Abrissen. Hierzu kann die Faserstoffbahn über einen rotierenden Zylinder geführt werden.Especially at high speeds, it is advantageous if the fibrous web is also supported in the area of electromagnetic waves. This stabilizes the Run of the fibrous web and reduces the risk of tearing. For this, the The fibrous web is guided over a rotating cylinder.

Je nach Art der Faserstoffbahn und/oder der Maschine ist es dabei durchaus möglich, daß die Trocknung der Faserstoffbahn zumindest überwiegend durch elektromagnetische Wellen erfolgt. Meistens wird jedoch die Trocknung auf konventionelle Weise, d.h. beispielsweise über beheizte Zylinder erfolgen, so daß elektromagnetische Wellen im wesentlichen nur zum Ausgleich von Feuchteunterschieden quer zur Faserstoffbahn dienen.Depending on the type of fibrous web and / or the machine, it is entirely possible that the drying of the fibrous web at least predominantly by electromagnetic waves occur. Most of the time, however, the drying on conventional way, i.e. for example via heated cylinders, so that electromagnetic waves essentially only to compensate for Differences in moisture serve across the fibrous web.

Als Mikrowellen-Sender kommen dabei vorzugsweise ein oder mehrere Hohlleiter zur Anwendung, die jeweils mit zumindest einer Mikrowellen-Quelle verbunden sind und wenigstens quer zur Faserstoffbahn möglichst gleichmäßig verteilt angeordnet sein sollten. Im Ergebnis entsteht eine relativ gleichmäßige Verteilung der Feldenergie der Mikrowellen quer zur Faserstoffbahn.One or more waveguides are preferably used as the microwave transmitter Application, which are each connected to at least one microwave source and at least transversely to the fibrous web as evenly distributed as possible should. The result is a relatively even distribution of field energy Microwaves across the fibrous web.

Zur Stützung sollte die Faserstoffbahn im Bereich der Mikrowellen über einen rotierenden Zylinder geführt werden.For support, the fibrous web should have a microwaves rotating cylinder.

Da die meist metallischen Zylinder zu einer Verringerung der Feldenergie der Mikrowellen in der Faserstoffbahn führen würden, sollte der Mantel des Zylinders oder eine äußere Beschichtung dieses Mantels aus einem Material bestehen, daß die Mikrowellen schlechter als die Faserstoffbahn absorbiert. Hierzu eignet sich beispielsweise Teflon. Die Stärke der Beschichtung sollte zwischen 5 und 150 mm, vorzugsweise zwischen 10 und 50 mm liegen.As the mostly metallic cylinders reduce the field energy of the Microwaves in the fibrous web would lead to the jacket of the cylinder or an outer coating of this jacket consist of a material that the Microwaves absorbed worse than the fibrous web. This is suitable for example Teflon. The thickness of the coating should be between 5 and 150 mm, are preferably between 10 and 50 mm.

Der Lauf der Faserstoffbahn kann jedoch auch für sich allein oder in Ergänzung von wenigstens einem Sieb unterstützt werden, dessen Material die Mikrowellen schlechter als die Faserstoffbahn absorbiert.However, the course of the fibrous web can also be used alone or in addition to at least one sieve is supported, the material of which the microwaves are worse than the fibrous web absorbs.

Im Falle des Einsatzes von Hochfrequenzwellen sollten die Elektroden die Form von Stabelektroden, Kondensatorplatten und/oder rotierende Zylindern haben.In the case of using high frequency waves, the electrodes should be in the form of Stick electrodes, capacitor plates and / or rotating cylinders.

Auch hierbei sollte die Faserstoffbahn im Bereich der Elektroden über einen rotierenden Zylinder geführt und vorzugsweise von einem Sieb gestützt sein.Here too, the fibrous web should rotate in the region of the electrodes Cylinder guided and preferably supported by a sieve.

Dabei ist es möglich, daß der vorzugsweise überwiegend metallisch ausgeführte Zylinder eine Elektrode bildet und auf der bezüglich der Faserstoffbahn gegenüberliegenden Seite zumindest eine Stabelektrode und/oder eine Kondensatorplatte anderer Polarität angeordnet ist. Als Schutzmaßnahme ist es dabei von Vorteil, wenn der Zylinder eine elektrisch isolierende, äußere Beschichtung besitzt. Es ist andererseits jedoch auch möglich, daß im Umschlingungsbereich des Zylinders zumindest zwei Stabelektroden verschiedener Polarität vorhanden sind, deren Hochfrequenzwellen teilweise die Faserstoffbahn durchdringen.It is possible that the preferably predominantly metallic Cylinder forms an electrode and on the with respect to the fibrous web opposite side at least one stick electrode and / or one Capacitor plate of different polarity is arranged. It is included as a protective measure an advantage if the cylinder has an electrically insulating outer coating. On the other hand, it is also possible that in the wrapping area of the cylinder there are at least two stick electrodes of different polarity, the High-frequency waves partially penetrate the fibrous web.

Unabhängig von der Art der Wellen, die auch kombiniert miteinander eingesetzt werden können, sollten diese Vorrichtungen eine elektromagnetische Abschirmung gegenüber der Umwelt besitzen.Regardless of the type of shaft, which can also be used in combination these devices should be shielded from electromagnetic interference own the environment.

Nachfolgend soll die Erfindung an mehreren Ausführungsbeispielen näher erläutert werden. In den beigefügten Zeichnungen zeigt:

  • Figur 1: eine Mikrowellenvorrichtung
  • Figur 2: eine Hochfrequenzvorrichtung mit Kondensatorplatte und
  • Figur 3: eine Hochfrequenzvorrichtung mit Stabelektroden.
    • The invention will be explained in more detail below using several exemplary embodiments. In the accompanying drawings:
  • Figure 1: a microwave device
  • Figure 2: a high frequency device with capacitor plate and
  • Figure 3: a high frequency device with stick electrodes.

    • Alle Figuren zeigen einen Querschnitt durch einen Zylinder 3 mit der erfindungsgemäßen Vorrichtung, wobei die Faserstoffbahn 1 den größten Teil des Umfangs des rotierenden Zylinders 3 umschlingt. Der Zylinder 3 ist hierbei nicht separat beheizt.All figures show a cross section through a cylinder 3 with the The device according to the invention, the fibrous web 1 covering most of the Loops around the circumference of the rotating cylinder 3. The cylinder 3 is not separate here heated.

    Gemäß Figur 1 ist entlang des Umschlingungsbereiches ein Mikrowellen-Sender 2 außerhalb des Zylinders 3 angeordnet.According to FIG. 1, there is a microwave transmitter 2 along the looping area arranged outside the cylinder 3.

    Der Mikrowellen-Sender 2 besteht aus einer Aneinanderreihung von mehreren quer zur Bahnlaufrichtung verlaufenden Hohlleitern mit rechteckigem Querschnitt, die jeweils mit einer Mikrowellen-Quelle verbunden sind. Es ist dabei jedoch auch möglich, die Hohlleiter mäanderförmig anzuordnen. Die davon ausgehenden Mikrowellen sorgen dafür, daß die feuchteren Stellen der Faserstoffbahn 1 stärker erwärmt und damit getrocknet werden als die übrigen Bereiche. Im Ergebnis entsteht ein vergleichmäßigtes Feuchtequerprofil.The microwave transmitter 2 consists of a series of several across Path running waveguides with a rectangular cross-section, each with are connected to a microwave source. However, it is also possible that Arrange waveguide meandering. The resulting microwaves provide for the fact that the wetter parts of the fibrous web 1 are heated up more and thus are dried than the other areas. The result is a more even one Moisture cross profile.

    Um den Mikrowellen-Sender 2 ist eine Abschirmung 6 angeordnet, so daß keine Mikrowellen diese Vorrichtung verlassen. Der Zylinder 3 besitzt eine ca. 2 cm dicke Beschichtung 4 aus Teflon, welche die Mikrowellen weniger stark absorbiert als die Faserstoffbahn 1. Die Stärke der Beschichtung 4 sorgt dafür, daß der metallische Bereich des Zylinders 3 möglichst weit weg von der Faserstoffbahn 1 liegt, so daß eine möglichst große Feldstärke der Mikrowellen in der Faserstoffbahn 1 gewährleistet ist.A shield 6 is arranged around the microwave transmitter 2, so that none Microwaves leave this device. The cylinder 3 is approximately 2 cm thick Coating 4 made of Teflon, which absorbs the microwaves less strongly than that Fibrous web 1. The thickness of the coating 4 ensures that the metallic Area of the cylinder 3 is as far away from the fibrous web 1, so that a the greatest possible field strength of the microwaves in the fibrous web 1 is guaranteed.

    Zur Stabilisierung des Laufes der Faserstoffbahn 1 dient ein mitlaufendes, bezüglich der Oberfläche des Zylinders 2 außen liegendes Sieb 5, welches ebenfalls aus einem Material besteht, das die Mikrowellen weniger stark absorbiert als die Faserstoffbahn 1.For the stabilization of the run of the fibrous web 1 is used, with respect to the Surface of the cylinder 2 outer screen 5, which also consists of a Material exists that absorbs the microwaves less strongly than the fibrous web 1.

    Die Figuren 2 und 3 zeigen Hochfrequenzvorrichtungen bei denen der Lauf der Faserstoffbahn 1 über ein mitlaufendes, außenliegendes Sieb 5 stabilisiert wird. Außerdem sind auch hier die Vorrichtungen mit einer Abschirmung 6 für die Hochfrequenzwellen versehen. Figures 2 and 3 show high frequency devices in which the run of the Fibrous web 1 is stabilized via a running, external sieve 5. In addition, here are the devices with a shield 6 for Provide high frequency waves.

    Die Faserstoffbahn 1 wird jedoch an mit einer Hochfrequenz-Quelle (HF) verbundenen Elektroden unterschiedlicher Polarität vorbeigeführt. Dies führt ebenfalls zur Erwärmung und Trocknung der feuchten Bereiche der Faserstoffbahn 1 mit dem Ergebnis eines relativ gleichmäßigen Feuchtequerprofil.However, the fibrous web 1 is connected to a high-frequency source (HF) Electrodes of different polarity passed. This also leads to warming and drying the moist areas of the fibrous web 1 with the result a relatively uniform moisture cross profile.

    In Figur 2 bildet der metallische, rotierende Zylinder 3 selbst eine mit der Hochfrequenz-Quelle verbundene Elektrode 7. Die Elektrode 7 der anderen Polarität wird von einer Kondensatorplatte gebildet, die im Umschlingungsbereich des Zylinders 3 angeordnet ist. Die Hochfrequenzwellen durchdringen dabei die Faserstoffbahn 1, was die Anordnung sehr wirksam macht. Wegen der Funktion des Zylinders 3 als Elektrode 7 sollte er eine elektrisch isolierende Beschichtung im Bereich der feuchten Faserstoffbahn 1 besitzen.In FIG. 2, the metallic, rotating cylinder 3 itself forms one with the high-frequency source connected electrode 7. The electrode 7 of the other polarity is of a Capacitor plate formed, which is arranged in the wrapping area of the cylinder 3 is. The high-frequency waves penetrate the fibrous web 1, which the Arrangement makes it very effective. Because of the function of the cylinder 3 as an electrode 7 it should have an electrically insulating coating in the moist area Own fibrous web 1.

    Im Gegensatz hierzu werden in Figur 3 alle Elektroden 7 von Stabelelektroden gebildet, die im Umschlingungsbereich des Zylinders 3 angeordnet sind. Die mit einer Hochfrequenz-Quelle (HF) verbundenen Elektroden sind dabei so gepolt, daß benachbarte Stabelektroden immer unterschiedliche Polarität aufweisen. Das sich zwischen den Elektroden 7 ausbildende Feld durchdringt dabei die Faserstoffbahn 1 zumindest teilweise, was ebenfalls zur Erwärmung und Trocknung der feuchten Stellen der Faserstoffbahn 1 führt.In contrast to this, all electrodes 7 are formed by stick electrodes in FIG. 3, which are arranged in the wrapping area of the cylinder 3. The one High-frequency source (HF) connected electrodes are polarized so that Adjacent stick electrodes always have different polarities. That I field forming between the electrodes 7 penetrates the fibrous web 1 at least partially, which also leads to the heating and drying of the damp areas the fibrous web 1 leads.

    Die Stabelektroden wie auch die Kondensatorplatte erstrecken sich im wesentlichen quer zur Faserstoffbahn 1 und parallel zum Zylinder 3.The stick electrodes as well as the capacitor plate extend essentially across the fibrous web 1 and parallel to the cylinder 3.

    Die Vorrichtungen können an mehreren Stellen einer Papier- oder Streichmaschine angeordnet sein. Desweiteren kann damit auch der gesamte Trocknungsvorgang realisiert werden. Vorzugsweise befinden sich derartige Vorrichtungen jedoch zur Feuchtequerprofilkorrektur in Trockenpartien mit konventionell beheizten Trockenzylindern, die von der Faserstoffbahn umschlungen sind.The devices can be in several places on a paper or coating machine be arranged. Furthermore, the entire drying process can will be realized. However, such devices are preferably for Moisture cross profile correction in dryer sections with conventionally heated Drying cylinders, which are wrapped in the fibrous web.

    Claims (20)

    Verfahren zur Feuchteprofilierung einer zu trocknenden Faserstoffbahn (1) in Maschinen zur Herstellung und/oder Veredelung derselben, dadurch gekennzeichnet, daß
    die Faserstoffbahn (1) elektromagnetischen Wellen in Form von Mikrowellen und/oder Hochfrequenzwellen ausgesetzt wird.    Method for moisture profiling a fibrous web (1) to be dried in machines for producing and / or finishing the same, characterized in that
    the fibrous web (1) is exposed to electromagnetic waves in the form of microwaves and / or high-frequency waves.         Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß
    die Feldenergie der elektromagnetischen Wellen quer zur Faserstoffbahn (1) möglichst gleichmäßig verteilt ist.    A method according to claim 1, characterized in that
    the field energy of the electromagnetic waves is distributed as evenly as possible across the fibrous web (1).         Verfahren nach Anspruch 1 oder 2, dadurch gekennzeichnet, daß
    die elektromagnetischen Wellen bei einem Trockengehalt der Faserstoffbahn (1) zwischen 60-95 % zum Einsatz kommen.    A method according to claim 1 or 2, characterized in that
    the electromagnetic waves are used when the dry matter content of the fibrous web (1) is between 60-95%.         Verfahren nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, daß
    die Faserstoffbahn (1) zumindest im Bereich der elektromagnetischen Wellen gestützt verläuft.    Method according to one of the preceding claims, characterized in that
    the fibrous web (1) runs at least in the region of the electromagnetic waves.         Verfahren nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, daß
    die Trocknung der Faserstoffbahn (1) zumindest überwiegend durch die elektromagnetischen Wellen erfolgt.    Method according to one of the preceding claims, characterized in that
    the fibrous web (1) is at least predominantly dried by the electromagnetic waves.         Verfahren nach einem der Ansprüche 1 bis 4, dadurch gekennzeichnet, daß
    die Trocknung der Faserstoffbahn (1) nur zu einem geringen Teil über die elektromagnetischen Wellen erfolgt und vorzugsweise zum Ausgleich von Feuchteunterschieden quer zur Faserstoffbahn (1) dient.     Method according to one of claims 1 to 4, characterized in that
    the fibrous web (1) is only dried to a small extent via the electromagnetic waves and is preferably used to compensate for moisture differences across the fibrous web (1).         Vorrichtung zur Durchführung des Verfahrens nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, daß
    die Faserstoffbahn (1) an zumindest einem Mikrowellen-Sender (2) vorbeigeführt wird.    Device for carrying out the method according to one of the preceding claims, characterized in that
    the fibrous web (1) is guided past at least one microwave transmitter (2).         Vorrichtung nach Anspruch 7, dadurch gekennzeichnet, daß
    der Mikrowellen-Sender (2) aus einem oder mehreren Hohlleitern besteht, die jeweils mit zumindest einer Mikrowellen-Quelle verbunden sind.    Apparatus according to claim 7, characterized in that
    the microwave transmitter (2) consists of one or more waveguides, each of which is connected to at least one microwave source.         Vorrichtung nach Anspruch 8, dadurch gekennzeichnet, daß
    die Hohlleiter quer zur Faserstoffbahn (1) möglichst gleichmäßig verteilt sind.    Apparatus according to claim 8, characterized in that
    the waveguides are distributed as evenly as possible across the fibrous web (1).         Vorrichtung nach einem der Ansprüche 7 bis 9, dadurch gekennzeichnet, daß
    die Faserstoffbahn (1) im Bereich eines Mikrowellen-Senders (2) über einen rotierenden Zylinder (3) geführt wird.    Device according to one of claims 7 to 9, characterized in that
    the fibrous web (1) is guided in the area of a microwave transmitter (2) via a rotating cylinder (3).         Vorrichtung nach Anspruch 10, dadurch gekennzeichnet, daß
    der Mantel des Zylinders (3) oder eine äußere Beschichtung (4) dieses Mantels aus einem Material besteht, welches die Mikrowellen schlechter als die Faserstoffbahn (1) absorbiert.    Apparatus according to claim 10, characterized in that
    the jacket of the cylinder (3) or an outer coating (4) of this jacket consists of a material which absorbs the microwaves less well than the fibrous web (1).         Vorrichtung nach Anspruch 11, dadurch gekennzeichnet, daß
    die Dicke der äußeren Beschichtung (4) zwischen 5 und 150 mm, insbesondere zwischen 10 und 50 mm liegt.    Device according to claim 11, characterized in that
    the thickness of the outer coating (4) is between 5 and 150 mm, in particular between 10 and 50 mm.         Vorrichtung nach einem der Ansprüche 7 bis 12, dadurch gekennzeichnet, daß
    der Lauf der Faserstoffbahn (1) von wenigstens einem Sieb (5) unterstützt wird, dessen Material die Mikrowellen schlechter als die Faserstoffbahn (1) absorbiert.    Device according to one of claims 7 to 12, characterized in that
    the run of the fibrous web (1) is supported by at least one sieve (5), the material of which absorbs the microwaves worse than the fibrous web (1).         Vorrichtung nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, daß
    die Faserstoffbahn (1) an zumindest zwei mit einer Hochfrequenz-Quelle verbundenen Elektroden (7) unterschiedlicher Polarität vorbeigeführt wird.     Device according to one of the preceding claims, characterized in that
    the fibrous web (1) is guided past at least two electrodes (7) of different polarity connected to a high-frequency source.         Vorrichtung nach Anspruch 14, dadurch gekennzeichnet, daß
    die Elektroden die Form von Stabelektroden, Kondensatorplatten und/oder rotierenden Zylindern (3) haben.    Device according to claim 14, characterized in that
    the electrodes are in the form of stick electrodes, capacitor plates and / or rotating cylinders (3).         Vorrichtung nach Anspruch 14 oder 15, dadurch gekennzeichnet, daß
    die Faserstoffbahn (1) im Bereich der Elektroden (7) über einen rotierenden Zylinder (3) geführt und vorzugsweise von einem Sieb (5) gestützt ist.    Apparatus according to claim 14 or 15, characterized in that
    the fibrous web (1) is guided in the region of the electrodes (7) over a rotating cylinder (3) and is preferably supported by a sieve (5).         Vorrichtung nach Anspruch 15 oder 16, dadurch gekennzeichnet, daß
    der vorzugsweise überwiegend metallisch ausgeführte Zylinder (3) eine Elektrode (7) bildet und auf der bezüglich der Faserstoffbahn (1) gegenüberliegende Seite zumindest eine Stabelektrode und/oder eine Kondensatorplatte anderer Polarität angeordnet ist.    Device according to claim 15 or 16, characterized in that
    the preferably predominantly metallic cylinder (3) forms an electrode (7) and at least one rod electrode and / or a capacitor plate of a different polarity is arranged on the side opposite the fibrous web (1).         Vorrichtung nach Anspruch 17, dadurch gekennzeichnet, daß
    der Zylinder (3) eine elektrisch isolierende, äußere Beschichtung besitzt.    Apparatus according to claim 17, characterized in that
    the cylinder (3) has an electrically insulating, outer coating.         Vorrichtung nach Anspruch 16, dadurch gekennzeichnet, daß
    im Umschlingungsbereich des Zylinders (3) zumindest zwei Stabelektroden verschiedener Polarität vorhanden sind, deren Hochfrequenzwellen teilweise die Faserstoffbahn (1) durchdringen.    Apparatus according to claim 16, characterized in that
    At least two rod electrodes of different polarity are present in the wrapping area of the cylinder (3), the high-frequency waves of which partially penetrate the fibrous web (1).         Vorrichtung nach einem der Ansprüche 7 bis 19, dadurch gekennzeichnet, daß
    die Vorrichtung eine elektromagnetische Abschirmung (6) besitzt.    Device according to one of claims 7 to 19, characterized in that
    the device has an electromagnetic shield (6).
    EP99112923A 1998-09-11 1999-07-05 Controlling the moisture profile Withdrawn EP0989231A3 (en)

    Applications Claiming Priority (2)

    Application Number Priority Date Filing Date Title
    DE19841638A DE19841638A1 (en) 1998-09-11 1998-09-11 Moisture profiling
    DE19841638 1998-09-11

    Publications (2)

    Publication Number Publication Date
    EP0989231A2 true EP0989231A2 (en) 2000-03-29
    EP0989231A3 EP0989231A3 (en) 2001-04-25

    Family

    ID=7880651

    Family Applications (1)

    Application Number Title Priority Date Filing Date
    EP99112923A Withdrawn EP0989231A3 (en) 1998-09-11 1999-07-05 Controlling the moisture profile

    Country Status (3)

    Country Link
    US (2) US6425190B1 (en)
    EP (1) EP0989231A3 (en)
    DE (1) DE19841638A1 (en)

    Cited By (3)

    * Cited by examiner, † Cited by third party
    Publication number Priority date Publication date Assignee Title
    US6736935B2 (en) 2002-06-27 2004-05-18 Kimberly-Clark Worldwide, Inc. Drying process having a profile leveling intermediate and final drying stages
    WO2004083523A1 (en) * 2003-03-21 2004-09-30 Saueressig Gmbh + Co. Production method for an absorbent fibre product and corresponding absorbent fibre product
    CN109631546A (en) * 2018-11-12 2019-04-16 芜湖顺成电子有限公司 A kind of spiral electric wire drying unit

    Families Citing this family (10)

    * Cited by examiner, † Cited by third party
    Publication number Priority date Publication date Assignee Title
    DE10305598A1 (en) * 2003-02-11 2004-08-19 Voith Paper Patent Gmbh Material web moisture content determination method, e.g. a paper or card web, whereby an infrared moisture sensor is used that is mounted on a beam so that it can be moved over the whole web width
    DE10319724A1 (en) * 2003-05-02 2005-01-20 Voith Paper Patent Gmbh Process to increase the dry matter content in a wet paper web by exposure to microwave energy
    DE10347587A1 (en) * 2003-10-14 2005-05-19 Voith Paper Patent Gmbh Papermaking assembly drying station or smoothing drum for wet web of carton, paper or tissue sets up oscillation in drying or smoothing station
    FI20051096A (en) * 2005-10-31 2007-05-01 Savcor Process Oy Procedure in a wet portion of a paper machine, cardboard machine or other similar forming machine
    DE102008038215A1 (en) * 2008-08-18 2010-02-25 Siemens Aktiengesellschaft Method and device for drying a paper web
    DE102008062320B3 (en) * 2008-12-15 2010-04-15 Siemens Aktiengesellschaft Drying chamber for the dielectric drying of a material, in particular a paper web
    ATE529568T1 (en) * 2008-12-23 2011-11-15 Tecnerga S R L SYSTEM FOR ADJUSTING AND CONTROLLING THE WATER CONTENT OF PAPER DURING THE PRODUCTION CYCLE
    US9481777B2 (en) 2012-03-30 2016-11-01 The Procter & Gamble Company Method of dewatering in a continuous high internal phase emulsion foam forming process
    CN108518951B (en) * 2018-03-27 2019-11-05 宁波雯泽纺织品有限公司 Textile processing drying equipment
    CN114608294B (en) * 2020-12-07 2023-09-08 辛集市祥光绒布有限公司 Large-scale vertical cloth drying device

    Citations (4)

    * Cited by examiner, † Cited by third party
    Publication number Priority date Publication date Assignee Title
    AU445577B2 (en) * 1968-06-14 1974-02-08 Ford Russell George Process and apparatus for moisture contents de-peaking and equalization
    US3952421A (en) * 1974-10-18 1976-04-27 Chemetron Corporation Dielectric heating arrangement for drying a continuously moving web of material
    DE3445615A1 (en) * 1984-12-14 1986-06-19 Maschinenfabrik Horst Kabus GmbH, 7085 Bopfingen Method for drying webs made of paper, textile or the like
    WO1992012291A1 (en) * 1991-01-07 1992-07-23 Sven Gunnar Nygren Controlling moisture content in a paper-making process

    Family Cites Families (18)

    * Cited by examiner, † Cited by third party
    Publication number Priority date Publication date Assignee Title
    DE697509C (en) * 1936-06-11 1940-10-16 Siemens Schuckertwerke Akt Ges Drying device for paper webs on paper machines
    DE691038C (en) * 1937-07-01 1940-05-15 Siemens Schuckertwerke Akt Ges Device for drying paper webs and similar material webs
    DE694637C (en) * 1937-09-03 1940-08-05 Siemens Schuckertwerke Akt Ges Device for heating, in particular drying, of wood, paper or similar objects in an electrical field
    US2319174A (en) * 1942-06-23 1943-05-11 Fred K H Levey Co Inc Method of and apparatus for printing
    GB1027589A (en) * 1964-06-04 1966-04-27 Fitchburg Paper Drying travelling webs
    DE1959116A1 (en) * 1969-11-25 1971-05-27 Boehmer Eisenwerk Kg Aufrueckvorrichtung for rail car
    US4188731A (en) * 1976-08-25 1980-02-19 Rauskolb Fred W Method and apparatus for eliminating wet streaks in fibrous sheets or webs by infra-red radiation
    DE2816551C3 (en) 1978-04-17 1981-11-26 SIEMENS AG AAAAA, 1000 Berlin und 8000 München Drying control on a paper machine
    FI74062C (en) * 1985-12-12 1987-12-10 Imatran Voima Oy FOERFARANDE OCH ANORDNING FOER MINSKNING HOEGFREKVENT ELENERGI AV FUKTIGHETSDIFFERENSERNA HOS EN ROERLIG BANA MEDELST.
    US4738752A (en) * 1986-08-12 1988-04-19 Beloit Corporation Heated extended nip press apparatus
    FI80099C (en) * 1986-10-31 1990-04-10 Imatran Voima Oy FOERFARANDE OCH ANORDNING FOER TORKNING AV ROERLIGT BANMATERIAL.
    US5064979A (en) * 1990-08-07 1991-11-12 W. R. Grace & Co.-Conn. Microwave air float bar for drying a traveling web
    ATE129067T1 (en) * 1990-12-17 1995-10-15 Per Erik Gustafsson ARRANGEMENT FOR GENERATING ENERGY AND METHOD FOR USE OF THE SAME.
    DE4121203A1 (en) * 1991-06-27 1993-01-14 Alfred Linden Varnished paper and cardboard dryer - has hollow conductors to deliver microwave energy to moving material across its line of travel
    FI103820B1 (en) * 1993-11-30 1999-09-30 Valmet Paper Machinery Inc Procedures for drying a paper web and drying parts for paper machine
    JP3077879B2 (en) * 1994-02-15 2000-08-21 インターナショナル・ビジネス・マシーンズ・コーポレ−ション Apparatus and method for applying microwave energy to a web-type quantified processing material
    US5659972A (en) * 1995-10-06 1997-08-26 Avery Dennison Corporation Apparatus and method for drying or curing web materials and coatings
    US5863613A (en) * 1996-12-20 1999-01-26 Ppg Industries, Inc. Apparatus and method for spray painting of an article

    Patent Citations (4)

    * Cited by examiner, † Cited by third party
    Publication number Priority date Publication date Assignee Title
    AU445577B2 (en) * 1968-06-14 1974-02-08 Ford Russell George Process and apparatus for moisture contents de-peaking and equalization
    US3952421A (en) * 1974-10-18 1976-04-27 Chemetron Corporation Dielectric heating arrangement for drying a continuously moving web of material
    DE3445615A1 (en) * 1984-12-14 1986-06-19 Maschinenfabrik Horst Kabus GmbH, 7085 Bopfingen Method for drying webs made of paper, textile or the like
    WO1992012291A1 (en) * 1991-01-07 1992-07-23 Sven Gunnar Nygren Controlling moisture content in a paper-making process

    Cited By (4)

    * Cited by examiner, † Cited by third party
    Publication number Priority date Publication date Assignee Title
    US6736935B2 (en) 2002-06-27 2004-05-18 Kimberly-Clark Worldwide, Inc. Drying process having a profile leveling intermediate and final drying stages
    WO2004083523A1 (en) * 2003-03-21 2004-09-30 Saueressig Gmbh + Co. Production method for an absorbent fibre product and corresponding absorbent fibre product
    US7758722B2 (en) 2003-03-21 2010-07-20 Saueressig Gmbh + Co. Production method for an absorbent fiber product and corresponding absorbent fiber product
    CN109631546A (en) * 2018-11-12 2019-04-16 芜湖顺成电子有限公司 A kind of spiral electric wire drying unit

    Also Published As

    Publication number Publication date
    US20020043004A1 (en) 2002-04-18
    US6425190B1 (en) 2002-07-30
    EP0989231A3 (en) 2001-04-25
    DE19841638A1 (en) 2000-03-16
    US6463677B2 (en) 2002-10-15

    Similar Documents

    Publication Publication Date Title
    EP0989231A2 (en) Controlling the moisture profile
    EP2622006B1 (en) Electrically insulating nanocomposite having semiconductive or non-conductive nanoparticles, use of said nanocomposite, and method for producing same
    DE2333732A1 (en) PROCESS AND EQUIPMENT FOR THE PRODUCTION OF FIBER-SHAPED, RAIL-SHAPED MATERIAL
    DE3937246C2 (en) calendering
    DE19901400A1 (en) Drying and smoothing unit for fibrous webs
    DE2518829C2 (en) Method and device for the continuous two-sided coating of a continuous web
    DE19855940A1 (en) Fibrous web drying
    AT399357B (en) CALENDAR FOR TREATING A TRACK, IN PARTICULAR A PAPER
    DE2742086A1 (en) DEVICE FOR DRYING THE SIZE OF GLASS SILK FAEDEN O.DGL.
    DE3715551A1 (en) Mfr. of paper with less flutter - by forming stronger edges to the web to prevent flutter
    WO2016180889A1 (en) Device for continuous heating of material
    EP3239397B1 (en) Method and assembly for producing a flat impregnated fibre product
    WO2013037931A1 (en) Device and method for controlling and regulating a paper machine
    WO2013037926A1 (en) Measurement system and method for determining and regulating coatings per unit area
    DE3209511A1 (en) METHOD FOR PRODUCING A SOFT AND SUCTIONABLE TRAIN
    DE102013204856A1 (en) Nanocomposite with electric fields grading nanopatterns, process for its preparation and its use
    EP2315872B1 (en) Method and device for drying a paper web
    DE102021121847B4 (en) Machine for producing and/or treating a fibrous web
    EP0013400A1 (en) Process for drying moist paper or cardboard webs
    EP0414762B1 (en) Process for pressing a continuous humid web, in particular a web of paper
    EP1964972A2 (en) Method for producing a coated length of fibre sheet, in particular paper or cardboard
    DE947327C (en) Device for heating, in particular drying, an item by the action of a capacitive high-frequency field
    DE102019117177A1 (en) Device for drying a wet fibrous web using a metal belt
    DE10148263A1 (en) Process for the production of a roll cover
    DE2511262C3 (en) Manufacturing process for fiber webs filled with curable fiber-synthetic resin precondensate

    Legal Events

    Date Code Title Description
    PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

    Free format text: ORIGINAL CODE: 0009012

    AK Designated contracting states

    Kind code of ref document: A2

    Designated state(s): DE FI SE

    AX Request for extension of the european patent

    Free format text: AL;LT;LV;MK;RO;SI

    RAP1 Party data changed (applicant data changed or rights of an application transferred)

    Owner name: VOITH PAPER PATENT GMBH

    PUAL Search report despatched

    Free format text: ORIGINAL CODE: 0009013

    AK Designated contracting states

    Kind code of ref document: A3

    Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE

    AX Request for extension of the european patent

    Free format text: AL;LT;LV;MK;RO;SI

    17P Request for examination filed

    Effective date: 20011025

    AKX Designation fees paid

    Free format text: DE FI SE

    17Q First examination report despatched

    Effective date: 20031117

    STAA Information on the status of an ep patent application or granted ep patent

    Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

    18D Application deemed to be withdrawn

    Effective date: 20040330