WO2010066290A1 - Séchoir à jets dirigés - Google Patents

Séchoir à jets dirigés Download PDF

Info

Publication number
WO2010066290A1
WO2010066290A1 PCT/EP2008/067141 EP2008067141W WO2010066290A1 WO 2010066290 A1 WO2010066290 A1 WO 2010066290A1 EP 2008067141 W EP2008067141 W EP 2008067141W WO 2010066290 A1 WO2010066290 A1 WO 2010066290A1
Authority
WO
WIPO (PCT)
Prior art keywords
web
support surface
openings
impingement dryer
drying gas
Prior art date
Application number
PCT/EP2008/067141
Other languages
English (en)
Other versions
WO2010066290A4 (fr
Inventor
Markku Lummila
Kari Juppi
Antti Komulainen
Original Assignee
Metso Paper, Inc.
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 Metso Paper, Inc. filed Critical Metso Paper, Inc.
Priority to PCT/EP2008/067141 priority Critical patent/WO2010066290A1/fr
Publication of WO2010066290A1 publication Critical patent/WO2010066290A1/fr
Publication of WO2010066290A4 publication Critical patent/WO2010066290A4/fr

Links

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
    • D21F5/18—Drying webs by hot air

Definitions

  • the invention relates to an impingement dryer for drying a web of fibrous material, e.g. paper, board or the like.
  • This stream of side gas 42 may cause the web 5 to rise or lift off at its edge portion 51.
  • an impingement dryer for drying a fibrous web which is carried by a support surface and opposite a nozzle plate.
  • the nozzle plate has openings for blowing a drying gas towards the web.
  • the distance between the nozzle plate and said support surface is larger in a support surface edge portion supporting an edge portion of the web than in a support surface central portion supporting a central portion of the web.
  • the inventors have found that the web travelling through the impingement dryer tends to rise or flutter in the edge portion and that a contact of the web with the nozzle plate above the web may initiate web breaks. Therefore, increasing the distance between support surface and nozzle plate in the edge portion of the web avoids web contact to the nozzle plate and the increased sectional area of the flow path of the side gas reduces its speed. Therefore, lifting the web edge portion is less likely.
  • neither the nozzle plate nor the support surface have to be flat; in particular various shapes of curvature especially along the machine direction are commonly used in impingement dryers and may be used here as well.
  • the curvature of the nozzle plate may be concave or convex and the corresponding support surface is suitably curved in a convex and concave shape, respectively.
  • the support surface may be selected from a group comprising fabrics, wires and rolls or similar materials suitable for supporting the web.
  • the nozzle plate has a central plate portion, and has a lateral plate portion facing the support surface edge portion.
  • This lateral plate portion may be parallel to the central plate portion.
  • the lateral plate portion includes an inclined plate portion which faces the support surface edge portion, and which is inclined with respect to the central plate portion, so that the distance between the lateral plate portion and the support surface increases towards the support surface edge.
  • the lateral plate portion includes a curved plate portion which faces the support surface edge portion, and which is curved, so that the distance between the lateral plate portion and the support surface increases towards the support surface edge.
  • the lateral plate portion is offset with respect to the central plate portion in a direction away from the support surface and may, in this form, be connected to the central plate portion by a step.
  • an adjustable edge plate may be provided between the lateral plate portion of the nozzle plate and the support surface edge portion so as to be movable towards and away from the central portion of the nozzle plate.
  • the adjustable edge plate may be flat and movable in parallel to the lateral plate portion, or the adjustable edge plate may be curved and movable in parallel to a curved lateral plate portion.
  • the extension direction of the support surface and the corresponding nozzle plate in the machine direction (MD) can be any direction with regard to gravity, i.e. substantially horizontal arrangements or substantially vertical arrangements of the mentioned plate/surface elements or combinations thereof are possible and can be used with the invention .
  • the central portion of the nozzle plate comprises openings that are directed to blow the drying gas in a direction perpendicular to the support surface and/or comprises openings which blow the drying gas in the moving direction of the web. Additionally or alternatively, it may be arranged that a plurality of openings of the nozzle plate are directed to blow the drying gas in a direction perpendicular to the support surface including the support surface edge portion. Additionally or alternatively, the lateral plate portion may comprise openings which are directed to blow the drying gas obliquely towards the edge of the support surface.
  • the nozzle plate is provided with at least one suction opening for the passage of used drying gas, wherein support blowing openings are provided on the nozzle plate which are directed to blow drying gas towards the support surface below said suction opening.
  • support blowing openings are provided on the nozzle plate which are directed to blow drying gas towards the support surface below said suction opening.
  • edge support blowing openings are provided, which are directed to blow drying gas to a support surface edge portion adjacent said suction opening.
  • the suction opening is formed in the nozzle plate, and its shape is selected form a group of shapes including a round hole, slits, discrete rows of openings, an array of openings, and openings covered with a grid.
  • the method of the invention for drying a fibrous web using impingement drying passing a web through an impingement dryer in which a drying gas is blown onto the passing web to be dried which is supported on an support surface.
  • blowing towards the edge portion of the web is made from further away from the web surface than blowing onto a central portion of the web.
  • the method comprises exhausting used drying gas including evaporated water from above the web in localized areas and blowing fresh drying gas onto the web in the vicinity of suction areas where the drying gas is exhausted.
  • the drying gas may be blown perpendicularly onto the web in a central portion, and may be blown obliquely and outwardly onto the edge portion of the web.
  • Control of the drying process may be achieved by control of openings of the nozzle plate in lateral plate portions of the nozzle plate by moving an edge plate in machine cross direction (CD) closing selected ones of the openings.
  • drying of the fibrous web is carried out after the edges of the web have been trimmed.
  • Fig. 1 is a schematic view of a part of a first embodiment of an impingement dryer as seen in machine direction;
  • Fig. 2 is a schematic view of a part of a second embodiment of an impingement dryer as seen in machine direction;
  • Fig. 3 is a schematic side view of an impingement dryer according to a third embodiment
  • Fig. 4 shows a schematic partial bottom view on nozzle plates of the apparatus of Fig. 3;
  • Fig. 5 shows an arrangement of openings in a side portion of a nozzle plate of an impingement dryer according to a fourth embodiment
  • Fig. 6 is a schematic view of a part of a fifth embodiment of an impingement dryer as seen in machine direction;
  • Fig. 7 is an explanatory drawing for explaining problems of impingement dryers of the prior art.
  • Fig. 1 shows a schematic view of a part of a first embodiment of an impingement dryer as seen in machine direction.
  • a support surface 2 on which a web 5 is supported.
  • the support surface can be a wire, a belt, a felt or similar equipment, which travels in the direction into the drawing plane of Fig. 1.
  • a box shaped blowing device 1 which blows drying gas 4 towards the web 5.
  • a nozzle plate On the surface of the blowing device 1 facing the support surface 2 and the web 5, respectively, there is provided a nozzle plate which has a central portion 11, a lateral portion 12 and a step portion 13 connecting the central portion 11 and the lateral portion 12.
  • an edge plate 3 is provided in front of the lateral portion 12 of the nozzle plate, which edge plate is movable along the drawing plane of Fig. 1, i.e. towards and away from the central portion 11 of the nozzle plate, so as to selectively close individual openings in the lateral portion 12 of the nozzle plate.
  • the left part of the web 5 in Fig. 1 is referenced with reference sign 51. There, it is indicated that the web does not lie flat but has the trend to lift off, which may cause contact to the lateral portion 12 of the nozzle plate and may initiate web breaks.
  • the lateral portion 12 is arranged 50-400mm away from the edge of the web 5 towards the central portion 11, preferably 150-300mm.
  • FIG. 2 shows another embodiment in schematic drawing, wherein the same elements have the same reference signs as those elements of Fig. 1, so that a detailed description of these elements may be omitted here.
  • the blowing device of Fig. 2 differs from that of Fig. 1 in that the central portion 11 of the nozzle plate is flat while the lateral portion 12 of the nozzle plate is inclined so as to lower from outside towards the center of the web.
  • the step portion 13 of the nozzle plate can be omitted.
  • an edge plate 3 slidably arranged opposite the lateral portion 12 of the nozzle plate, so as to selectively close openings in that lateral portion 12.
  • the inclined lateral portion 12 is arranged in a distance from the web 5, so that even an uplifted edge portion 51 of the web 5 will not contact the nozzle plate.
  • FIG. 5 shows a modification of an inclined nozzle plate lateral portion 12 which can be used in the general layout of the blowing device as shown in Fig. 2.
  • an oblique nozzle plate lateral portion 12 has openings 15 provided in horizontally arranged portions of the inclined nozzle plate lateral portion 12, so that a drying gas 4 is vertically (i.e. perpendicularly with respect to the support surface (not shown) ) blown downwards towards the web 5. This is also indicated with the vertical arrows in Fig. 2 opposite the uplifted web portion 51.
  • Fig. 3 and Fig. 4 show a schematical side view and a bottom view in which blowing devices 1 of the type shown in Fig. 1, 2 or 5 are arranged in a row and under which the web 5 passes, while being supported on the support surface 2.
  • the support surface 2 is a wire which runs over rolls 6 to move with the web carried thereon along the row or array of blowing devices 1.
  • the blowing devices 1 each blow drying gases 4 towards the surface of the web 5. When the drying gas has taken up evaporated water, it is removed from the space between the nozzle plates of the blowing devices 1 and the web.
  • the used drying gas is indicated with reference sign 43 in Fig. 3.
  • drying gas 44 is jetted towards a point where the used drying gas 43 is removed from the web.
  • the drying gas jets 43 serve to hold the web 5 down on the support surface 2.
  • FIG. 4 the apparatus of Fig. 3 is shown as seen from the web that is looking from the web upwards to the nozzle plate of the individual blowing devices.
  • Fig. 4 there is a number of individual nozzle plates 11, 12 each belonging to one of the blowing devices 1 of Fig. 3.
  • Each nozzle plate 11, 12 of each blowing device 1 is divided into a central portion 11 and two lateral portions 12, of which only one is shown here because the arrangement is substantially symmetric.
  • individual openings are indicated with reference sign 15 and are distributed over the nozzle plate in regular or irregular patterns in a number and shape adapted for the respective drying task.
  • Fig. 4 the apparatus of Fig. 3 is shown as seen from the web that is looking from the web upwards to the nozzle plate of the individual blowing devices.
  • FIG. 4 there is a number of individual nozzle plates 11, 12 each belonging to one of the blowing devices 1 of Fig. 3.
  • Each nozzle plate 11, 12 of each blowing device 1 is divided into a central portion 11 and two lateral portions 12, of which only
  • the edge plate 3 is arranged to overlap a part of the lateral portion 12 of the nozzle plate, so as to close openings 15 at need.
  • the edge plate 3 can extend further over suction openings than over blowing openings, which also contributes to avoid edge lifting of the web 5.
  • a grid 14 indicating a grid in front of a channel or passage, so as to protect the exhaust opening for used drying gas 43 from debris.
  • the grid 14 can be replaced by slits or the like, and the channels for removing used drying gas may also be tubes, slits or may have any other desired shape.
  • FI 20080300 filed on April 21, 2008 which shows various arrangements of openings and channels for fresh and used drying gas. Therefore, in this respect, especially the layouts of Fig. 2, 3a, 3b, 4a, 4b are included in this specification by way of reference.
  • Fig. 6 shows another embodiment in a similar view as in Fig. 1 and Fig. 2 in which the lateral portion 12 of the nozzle plate is curved and is offset or stepped from the central portion 11 of the nozzle plate.
  • This central portion 11 of the nozzle plate is connected at its edge by a step portion 13 to the lateral portion 12.
  • the lateral portion 12 is curved, so that its distance from the support surface 2 carrying the web 5 increases when approaching the edge of the web.
  • the lateral portion 12 of the nozzle plate also has openings which may be arranged to jet the drying gas 4 vertically or perpendicularly to the web or the support surface; or they may be arranged such that they release the drying gas 4 substantially perpendicular to the curved surface of the lateral portion 12 of the nozzle plate.
  • an edge plate 3 which can be used to close a selected number of openings of the lateral portion 12 of the nozzle plate if required.
  • the edge plate 3 is also curved in a manner to match the curvature of the lateral portion 12 of the nozzle plate.
  • the edge plate 3 in Fig. 6 is arranged to pivot around a fulcrum 31. In this way, it can be easier to control the movement of the edge plate, since a stiffer body of the edge plate can be generated when putting the construction shown in Fig. 6 into practice.
  • the other elements of the blowing device 1 of Fig. 6 which have the same reference signs as that of Fig. 1 and Fig. 2 are similar and for their description reference to the mentioned figures appears sufficient.
  • Fig. 1, Fig. 2 and Fig. 6 only show one side of the blowing device which extends in the machine cross direction to the other edge portion of the web. Of course, at the other end of the blowing device, there is the same edge portion design as shown in Fig. 1, 2 and 6 in a symmetrical arrangement.
  • the support surface 2 has been shown to be a substantially flat surface extending horizontally, on which the web 5 is borne.
  • the support surface 2 can be curved and may have any direction with regard to gravity, and suitable means can be provided to carry the web on the surface.
  • the surface may be arranged above the web, holding it attached thereto by negative pressure.
  • a big wire covered vacuum roll can also be used as support surface 2.
  • multiple dryers may be provided in subsequent order and also in a way that they act on different sides of the web. In all these arrangements, the invention may be applied in the edge portion of the web in order to avoid web breaks.
  • the impingement dryer may be surrounded by a suitable housing which allows maintaining the temperatures inside the dryer, promotes the intended gas flows and protects the environment around the machine from the considerably hot drying gases which are used in impingement dryers .

Landscapes

  • Drying Of Solid Materials (AREA)

Abstract

La présente invention concerne un séchoir à jets dirigés destiné au séchage d'une nappe de fibres (5) et reposant sur une surface support (2) en regard d'une plaque à buses dont les ouvertures servent à souffler un gaz de séchage en direction de la nappe. Dans la zone de la bordure de la surface support (2) servant à supporter une partie en bordure de la nappe, la distance entre ladite plaque à buses (12) et ladite surface support est supérieure à ce qu'elle est dans la partie centrale de la surface support (11) servant à supporter une partie centrale de la nappe (5).
PCT/EP2008/067141 2008-12-09 2008-12-09 Séchoir à jets dirigés WO2010066290A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
PCT/EP2008/067141 WO2010066290A1 (fr) 2008-12-09 2008-12-09 Séchoir à jets dirigés

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/EP2008/067141 WO2010066290A1 (fr) 2008-12-09 2008-12-09 Séchoir à jets dirigés

Publications (2)

Publication Number Publication Date
WO2010066290A1 true WO2010066290A1 (fr) 2010-06-17
WO2010066290A4 WO2010066290A4 (fr) 2010-09-23

Family

ID=41682581

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP2008/067141 WO2010066290A1 (fr) 2008-12-09 2008-12-09 Séchoir à jets dirigés

Country Status (1)

Country Link
WO (1) WO2010066290A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102997632A (zh) * 2012-11-19 2013-03-27 王兆进 一种具有射流系统、红外系统和射流系统的节能干燥器

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3895449A (en) * 1973-10-10 1975-07-22 Beloit Corp Air impingement system
WO1999051813A1 (fr) * 1998-04-03 1999-10-14 Valmet Corporation Procede et appareil de regulation de la temperature dans la section de sechage d'une machine a papier ou analogue
WO2000001883A1 (fr) * 1998-07-01 2000-01-13 The Procter & Gamble Company Procede d'elimination d'eau d'une bande fibreuse au moyen d'un gaz de convection d'inversion de flux oscillatoire

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3895449A (en) * 1973-10-10 1975-07-22 Beloit Corp Air impingement system
WO1999051813A1 (fr) * 1998-04-03 1999-10-14 Valmet Corporation Procede et appareil de regulation de la temperature dans la section de sechage d'une machine a papier ou analogue
WO2000001883A1 (fr) * 1998-07-01 2000-01-13 The Procter & Gamble Company Procede d'elimination d'eau d'une bande fibreuse au moyen d'un gaz de convection d'inversion de flux oscillatoire

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102997632A (zh) * 2012-11-19 2013-03-27 王兆进 一种具有射流系统、红外系统和射流系统的节能干燥器

Also Published As

Publication number Publication date
WO2010066290A4 (fr) 2010-09-23

Similar Documents

Publication Publication Date Title
FI104000B (fi) Telan, sylinterin tai vastaavan ympärille sovitettu päällepuhallusjärjestelmä paperikoneen tai vastaavan kuivatusosassa
JP3305802B2 (ja) ウエブ材の無接触空気乾燥方法並びに該方法によるノズル吹き出しボックス及びパルプドライヤ
US4551203A (en) Method and arrangement for guiding a paper web from the press section to the drying section
US7036242B2 (en) Impingement drying unit and a dryer section
FI62571C (fi) Anordning vid flercylindertork i en pappersmaskin
PL91256B1 (fr)
FI95732B (fi) Laite paperikoneen kuivatusosassa
US6003241A (en) Drying unit and dryer section that makes use of such units
EP0638159B1 (fr) Caisson de soufflage a buses multifonctionnelles
WO2010066290A1 (fr) Séchoir à jets dirigés
US5214861A (en) Blow and air-conditioning device for an inverted cylinder group in the drying section of a paper machine
US7510069B2 (en) Vacuum belt conveyor for transferring a web threading tail in a web manufacturing machine
US6101735A (en) Dryer section in a paper machine in which impingement and/or ventilation hoods are used
US6003245A (en) Method for optimizing of evaporation drying of paper, runnability, and of paper quality as well as dryer section that makes use of the method in a paper machine
CA2859146C (fr) Caisson de sechage de pate de cellulose ayant des caissons de soufflage
US5718058A (en) Process and apparatus for the traveling of a paper tail from a first to a second handling station in a paper machine
US6493962B2 (en) Drying section
EP1075565B1 (fr) Chaine et procede de sechage de pate
FI124074B (fi) Menetelmä kaasuvirtojen aiheuttamien ajettavuusongelmien pienentämiseksi kuiturainan päällepuhalluskuivaimessa ja päällepuhalluskuivain
EP1736597B1 (fr) Section sèche d' une machine a papier, arrangement et méthode pour la diminution de la propagation de la poussière
JPS59100790A (ja) 抄紙機の乾燥部署において紙ウエブの走行を安定化する方法および装置
US6725569B2 (en) Device and method for ventilating an offset pocket space in a papermaking machine
JP5461153B2 (ja) 熱処理装置
WO2002070819A1 (fr) Dispositif situe dans la section de sechage d'une machine a papier
JPH06173188A (ja) 抄紙機のドライヤ

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 08875432

Country of ref document: EP

Kind code of ref document: A1

DPE1 Request for preliminary examination filed after expiration of 19th month from priority date (pct application filed from 20040101)
NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 08875432

Country of ref document: EP

Kind code of ref document: A1