Dryer section assembly for drying a paper web, usage of an infrared device for drying a paper web and method of drying a paper web

Abstract

The present invention relates to dryer section assembly (1) for drying a paper web (W), usage of an infrared (IR) device for drying a paper web (W) in a dryer section assembly (1) and a method of drying a paper web (W) in a dryer section assembly (1) during paper production. The dryer section assembly (1) comprises: a plurality of cylinders (12), wherein the plurality of cylinders (10) defines a cylinder inter-space (16) between at least two adjacent cylinders of the plurality of cylinders (10), a support device (30) comprising a support member (32) which is arranged in said cylinder inter-space (16) and extends in an elongated manner in said cylinder inter-space (16), , an infrared (IR) device (60) connected to and supported by the support member (32) and comprising a plurality of IR modules (62), optionally a plurality of electrically-powered IR modules, which are configured to emit infrared light towards a portion of said paper web (W) moving through said cylinder inter-space (16), wherein the IR device (60) is configured to cool the IR modules (62) by means of air in a convective manner.

Description

Field

[0001] The present invention relates to dryer section assembly for drying a paper web, usage of an infrared (IR) device for drying a paper web in a dryer section assembly and a method of drying a paper web in a dryer section assembly during paper production.Background

[0002] Typically, the papermaking process during paper production includes various sections in which the paper is formed from raw material (e.g. a wet fiber suspension), pressed, coated and / or dried one or more times, depending on the actual papermaking process and desired end product.

[0003] In said papermaking process during paper production, a dryer section is typically formed of a plurality of drying cylinders which are heated by hot steam and which apply heat and thus dry the paper web moving in contact along the outer circumferential surface of the drying cylinders, while the paper web is guided and pressed against the drying cylinders via one or more drying felts. Said dryer section typically also includes a type of housing or hood accommodating the various components of the dryer section. The housing or hood also retains and contains the heat and humidity (e.g. steam) resulting from the drying process as well as the dust from residual paper material. Conventionally, so called blow doctor devices are known as a combination of a doctor device (e.g. a mechanical doctor blade) for removing residual paper material from the drying cylinders and a ventilation device for providing an air stream directed towards the moving paper web and allowing removal of air of high temperature and high humidity from the moving paper web, thus improving temperature and / or humidity management.

[0004] Due to heat, humidity and dust from residual paper material, the environmental and climatic conditions inside the dryer section thus provide challenging for the involved components. On the other hand, it is desirable to manage the environmental and climatic conditions inside the dryer section (e.g. by means of temperature control and ventilation) so as to avoid damage to the moving paper web and obtain a desired quality of the finished product.

[0005] However, proper management of environmental and climatic conditions (such as temperature, humidity, dust etc.) inside the dryer section still provides challenging, especially due to the narrow und complex layout of cylinders, felts, moving paper web and other components in the dryer section. For example, a cylinder inter-space (also called a "pocket" in the art) may be present between adjacent cylinders, and temperature and humidity management in said cylinder inter-space (also called "pocket ventilation") may prove particularly difficult. While blow doctor devices may provide some ventilation to said cylinder inter-space, it would also be desirable to provide additional heating capabilities inside said cylinder inter-space for better temperature and humidity management.

[0006] Conventionally, gas-powered infrared heating devices or electrically-powered infrared heating devices may be used in certain process steps, such as the coating section for coat drying, where environmental and climatic conditions easier to cope with than in the dryer section. Application of such infrared heating devices (in particular electrically-powered infrared heating devices) inside the dryer section is particularly difficult with regard to stable and efficient operation (e.g. satisfying cooling needs of such heating devices and so on) needs as well as operational safety (e.g. minimizing fire hazards) due to heat, humidity and dust from residual paper material inside the dryer section.

[0007] On the other hand, electrically-powered infrared heating devices may further improve the drying performance in the dryer section, may offer the ability of using energy from renewable sources (such as wind and solar energy) and may further offer higher flexibility with regard to price differences between different energy sources (such as natural gas prices vs. electricity prices) and allows to react to dynamic electricity prices in the energy market (e.g. increasing / shifting electricity consumption at / towards times with lower electricity prices due to an abundance of wind and / or solar energy), thereby increasing cost-effectiveness and reducing ecological footprint.

[0008] There is thus a need for new techniques to provide additional heating capabilities inside the dryer section (in particular inside said cylinder inter-space) for improved temperature and humidity management by means of electrically-powered infrared heating devices, while avoiding or eliminating the above-described difficulties.Summary

[0009] By the present invention, a dryer section assembly for drying a paper web, usage of an infrared (IR) device for drying a paper web in a dryer section assembly and a method of drying a paper web in a dryer section assembly during paper production are provided, which allow to further improve the drying performance in the dryer section, further improve temperature and humidity management, increase cost-effectiveness and reduce ecological footprint.

[0010] Further, the present invention not only provides required convective cooling to infrared (IR) modules by means of an airflow inside a support member in the dryer section assembly, but may also allow to generate an air cushion towards the paper web and purge dust accumulations via the airflow used for convective cooling.

[0011] Furthermore, the use of a support member in the cylinder inter-space allows to use already present components, such as a beam element of a blow doctor device or a paper web stabilizer, for supporting an IR device, thereby providing stable support for the IR device and additional components and eliminating or at least minimizing the need for additional support components.

[0012] Moreover, the IR modules of the IR device may be controllable individually or in zones, making it possible to react to non-uniform drying of the paper web W in the dryer section assembly, thereby allowing to improve the drying efficiency and drying performance as well as increasing flexibility of the drying process (e.g. allowing spot drying).

[0013] In addition, the use of IR modules (in particular electrically-powered IR modules) allows to more easily upscale (i.e. increase) drying capacity of a dryer section without significantly changing the overall construction and size of existing dryer sections in papermaking machines, thereby allowing to increase the drying performance without increasing the size and space required for papermaking machines and allowing to reduce costs for retrofitting existing papermaking machines.

[0014] Furthermore, the dryer section assembly of the present invention may also allow easy access to the support member and the IR modules attached thereto for inspection, maintenance and / or repair, thereby reducing maintenance costs and down-time of the dryer section assembly.

[0015] To this end, the present invention provides a dryer section assembly for drying a paper web during paper production, the dryer section assembly comprising: a plurality of cylinders, wherein at least some cylinders of the plurality of cylinders are configured as drying cylinders, which define a circumferential contact surface and are configured to guide the paper web at least partially on said circumferential contact surface in a paper conveying direction while drying the paper web by application of heat to the paper web via said circumferential contact surface, wherein the plurality of cylinders defines a cylinder inter-space between at least two adjacent cylinders of the plurality of cylinders, a support device comprising a support member which is arranged in said cylinder inter-space and extends in an elongated manner in said cylinder inter-space, , an infrared (IR) device connected to and supported by the support member and including a plurality of IR modules, optionally a plurality of electrically-powered IR modules, which are configured to emit infrared light towards a portion of said paper web moving through said cylinder inter-space, wherein the IR device is configured to cool the IR modules by means of air in a convective manner.

[0016] In an exemplary embodiment, the support member may comprise an internal space configured to receive inflowing air and to define an airflow inside the support member, and the IR device may be configured to cool the IR modules in a convective manner by means of air provided from the airflow inside the support member.

[0017] Alternatively or additionally, the IR device may be configured to cool the IR modules in a convective manner by means of air supplied by one or more cooling air supply lines which are comprised in the dryer section assembly and are in fluid connection with the IR modules and provided separate from the support member.

[0018] The support device may further comprise a doctor blade which is configured to remove residual paper material from the circumferential contact surface of a respective one of the plurality of cylinders. Additionally or alternatively, the support device may further comprise one or more blow openings which are provided in the support member. The support device may be configured so as to allow at least part of air from the airflow inside the support member to be branched off via the one or more blow openings. The one or more blow openings may be arranged so as to face the portion of the paper web moving through said cylinder inter-space, whereby (e.g. during operation of the dryer section assembly) said branched-off air may be directed towards the portion of the paper web moving through said cylinder inter-space. Optionally, the branched-off air may be directed towards a portion of the paper web upstream said portion of the paper web irradiated by infrared light from the plurality of IR modules.

[0019] The support member may comprise a support member housing which extends in an elongated manner in said cylinder inter-space along a longitudinal direction of the support member housing. The support member housing may comprise a plurality of outer wall portions which at least partially define the support member (e.g. the internal space of the support member). Optionally, the support member housing may have a substantially triangular cross-sectional shape when viewed along the longitudinal direction of the support member housing.

[0020] The support member housing may further comprise a first outer wall portion of the plurality of outer wall portion, the first outer wall portion being arranged so as to face the portion of the paper web moving through said cylinder inter-space, wherein the first outer wall portion may comprise an outer wall opening. The plurality of IR modules may be arranged at least partially inside the support member housing and may be exposed at least partially through said outer wall opening so as to allow to emit infrared light towards the paper web moving through said cylinder inter-space. Optionally, the doctor blade may be attached to said first outer wall portion of the support member housing, for example by means of an extension portion extending from said first outer wall portion. Further optionally, the support member housing may comprise an infrared-transmissive wall opening cover which is connected to the first outer wall portion and covers the outer wall opening of the first outer wall portion in a dust-proof and / or airtight manner.

[0021] The support member may further comprise an air guiding means which is arranged inside the support member housing and at least partially defines the airflow inside the support member, wherein the air guiding means may at least partially define an air passageway configured to allow air to pass therethrough to provide convective cooling to the IR modules. The plurality of IR modules may be arranged at least partially inside the support member housing between the first outer wall portion and the air guiding means. Optionally, the support member may further comprise a mounting element arranged inside the internal space of support member and configured for mounting the IR modules thereto.

[0022] The air guiding means may comprise an internal guide wall connected to the support member housing at a first end portion of the internal guide wall. The internal guide wall may define an air distribution chamber inside the support member (e.g. inside the internal space of the support member), said air distribution chamber extending along the longitudinal direction of the support member housing. The internal guide wall may further define an air passage opening between a second end portion of the internal guide wall and the support member housing. The air passage opening may be configured to allow air to be discharged from the air distribution chamber towards the first outer wall portion and the IR modules. The first outer wall portion and the IR modules may define the air passageway configured to allow air, which has passed through the air passage opening, to pass therethrough to provide convective cooling to the IR modules.

[0023] The support member may be further configured to discharge air having cooled the IR modules to the cylinder inter-space, optionally towards the portion of the paper web moving through said cylinder inter-space. In said support member, the air passageway may be further configured to guide air through an inside and / or along an outer surface of the IR modules for cooling and to discharge the air having passed and cooled the IR modules from the support member towards the portion of the paper web moving through said cylinder inter-space, optionally through the one or more blow openings provided in the support member.

[0024] One, several or all of the IR modules may respectively comprise an infrared-transmissive IR device cover portion covering one or more IR emitting units of the respective IR module and being spaced apart from said IR emitting units so as to allow passage of air between the transparent IR device cover portion and the IR emitting units.

[0025] The air passageway may be further configured to guide air through an inside and / or along an outer surface of the IR modules for cooling and to discharge the air having passed and cooled the IR modules from the internal space of the support member through one or more air discharge ducts, which are respectively attached to one or more outer wall portion of the plurality of outer wall portions and in fluid connection with the internal space of the support member so as to receive the air discharged from the internal space of the support member.

[0026] The IR device may comprise an IR device housing, which extends in an elongated manner in said cylinder inter-space along a longitudinal direction of the IR device housing and which accommodates the IR modules of the IR device in an internal space thereof. The support member may comprise a plurality of support links which are connected with one end thereof to the support member housing and which are connected with the other end thereof to the IR device housing so as to hingedly connect the support member housing and the IR device housing with each other. At least one support link may comprise an internal channel which is in fluid connection with both the support member (e.g. the internal space of the support member) and the internal space of the IR device housing so as to allow air to flow from the support member to the IR device housing for convective cooling the IR modules. In addition or as an alternative to above-described internal channel, air for convective cooling the IR modules may be supplied to the internal space of the IR device housing by the one or more cooling air supply lines which are comprised in the dryer section assembly and are in fluid connection with the IR modules and provided separate from the support member. Optionally, by means of the hinge connection between the support member housing and the IR device housing, the IR device housing may be pivotable between a first pivotal position, in which the IR device housing is positioned away from the paper web moving through said cylinder inter-space and is positioned closer to the support member housing, and a second pivotal position, in which the IR device housing is positioned closer to the paper web moving through said cylinder inter-space and is positioned away from the support member housing. Further optionally, the IR device housing may be pivotable to any position between the first pivotal position and second pivotal position.

[0027] The support device may further comprise one or more air inlet ducts, which are respectively attached to the support member and in fluid connection with the internal space of the support member so as to introduce air into the internal space of the support member. Optionally, the one or more air inlet ducts may extend through respective ones of the outer wall portions of the outer support member housing into the internal space and may be connected to the internal guide wall and open into the air distribution chamber.

[0028] The support member may further include a fire detection means which is arranged on or inside of at least one of the support device and IR device and which is configured to detect and provide a notification of a fire. The dryer section assembly may further include a fire-fighting system which is in fluid connection with the support device and the IR device and is configured to introduce fire-extinguishing and / or fire-retarding gas into the support device and the IR device upon notification of a fire from the fire detection means.

[0029] The dryer section assembly may be configured as a double-felted dryer section assembly, which may further comprise a first drying felt and a second drying felt, wherein the plurality of cylinders may comprise a plurality of first cylinders and a plurality of second cylinders. The first cylinders may be configured to be at least partially wrapped by the first drying felt and the second cylinders may be configured to be at least partially wrapped by the second drying felt. The dryer section assembly may be configured for transferring the paper web between the first cylinders and the second cylinders at least partially by a free draw in a free draw section. The infrared device may be configured to emit infrared light towards at least the paper web in the free draw section.

[0030] As an example, the first cylinders may include a first drying cylinder and the second cylinders may include a second drying cylinder, wherein the drying cylinders may be configured to guide the paper web at least partially on said circumferential contact surface in the paper conveying direction between the circumferential contact surface and the corresponding one of the first and second drying felts, and to dry the paper web by application of heat to the paper web via said circumferential contact surface. The first cylinders may include a first felt guide cylinder and the second cylinders may include a second felt guide cylinder, wherein the felt guide cylinders may be configured to support and guide the corresponding one of the first and second drying felts, the first and second drying felts may be configured to support the paper web and urge the paper web towards the circumferential contact surface of the drying cylinders, and the cylinder inter-space may be defined at least between the first drying cylinder, the second drying cylinder, the first felt guide cylinder and the second felt guide cylinder.

[0031] The present invention further provides the usage of an infrared (IR) device for drying a paper web in a cylinder inter-space between at least two cylinders of the plurality of cylinders of a dryer section assembly (wherein the dryer section assembly may optionally be a dryer section assembly as described in this application) during paper production, wherein the IR device includes a plurality of IR modules, optionally a plurality of electrically-powered IR modules, and being connected to and supported by a support member which is arranged in said cylinder inter-space and extends in an elongated manner in said cylinder inter-space, wherein the IR device is cooled by air, which flows in an internal space of the support member and is guided to the IR modules for convective cooling of the IR modules, and / or air, which is supplied by one or more cooling air supply lines of the dryer section assembly, which are in fluid connection with the IR modules and provided separate from the support member.

[0032] The present invention further provides a method of drying a paper web in a dryer section assembly during paper production, the method comprising: arranging a support device and an infrared (IR) device in a cylinder inter-space between at least two adjacent cylinders of the plurality of cylinders of a dryer section assembly (wherein the dryer section assembly may optionally be a dryer section assembly as described in this application), wherein the support device is connected to and supporting the IR device, and the IR device having a plurality of IR modules, optionally a plurality of electrically-powered IR modules; air-cooling the IR modules of the IR device; drying and / or ventilating the paper web moving through said cylinder inter-space by: emitting infrared light by means of the air-cooled IR modules towards the paper web moving through said cylinder inter-space and / or blowing air from the support device towards the paper web moving through said cylinder inter-space. Optionally, the air blown towards the paper web may correspond to or may at least partially include the air heated during air-cooling the IR modules of the IR device.Brief Description of the Drawings

[0033] Fig. 1 is a perspective view illustrating a dryer section assembly according to various exemplary embodiments of the present invention. Fig. 2 is a cross-sectional view illustrating a dryer section assembly according various exemplary embodiments of to the present invention. Fig. 3 and 4 are partial perspective views illustrating a support device in a dryer section assembly according to various exemplary embodiments of the present invention. Fig. 5 is a perspective view illustrating a support device inside a cylinder inter-space of a dryer section assembly according to various exemplary embodiments of the present invention. Fig. 6 is a cross-sectional view illustrating a support device inside a cylinder inter-space of a dryer section assembly according to various exemplary embodiments of the present invention. Fig. 7 is a perspective view illustrating a support device according to various exemplary embodiments of the present invention. Fig. 8 is an enlarged view of a longitudinal end portion of the support device shown in Fig. 7 with a first longitudinal end wall portion removed. Fig. 9 illustrates a infrared device with infrared modules arranged in a single row. Fig. 10 illustrates a infrared device with infrared modules provided in two rows stacked one above the other. Fig. 11 is a perspective view, further illustrating the infrared device of Fig. 10. Fig. 12 is a cross-sectional view illustrating a support device and an airflow according to an exemplary embodiment of the present invention. Fig. 13 is a perspective view further illustrating the airflow according to the exemplary embodiment of Fig. 12. Fig. 14 is a cross-sectional view illustrating a support device and an airflow according to a further exemplary embodiment of the present invention. Fig. 15 is a perspective view further illustrating the airflow according to the further exemplary embodiment of Fig. 14. Fig. 16 is a cross-sectional view illustrating a support device and an airflow according to yet a further exemplary embodiment of the present invention. Fig. 17 is a perspective view further illustrating the airflow according to the further exemplary embodiment of Fig. 16. Fig. 18 is a cross-sectional view illustrating a support device and an IR device with an IR device housing in a first pivotal position according to an exemplary embodiment of the present invention. Fig. 19 is a cross-sectional view illustrating a support device and an IR device with an IR device housing in a second pivotal position according to an exemplary embodiment of the present invention. Fig. 20 is a cross-sectional view illustrating a support device and an IR device with an IR device housing connected to a separate cooling air supply line according to an exemplary embodiment of the present invention. Fig. 21 is a drawing showing schematically a configuration of a control device, fire detection means and fire-fighting system in a dryer section assembly according to an exemplary embodiment of the present invention. Fig. 22 is a drawing illustrating a method of drying a paper web in a dryer section assembly during paper production according to an embodiment of the present invention.

[0034] It should be understood that the appended drawings are not necessarily to scale, presenting a somewhat simplified representation of various features illustrative of the basic principles of the present invention. The specific design features of the present invention as disclosed herein, including, for example, specific dimensions, orientations, locations, and shapes will be determined in part by the particular intended application and use environment.

[0035] In the figures, the same reference numbers refer to the same or equivalent components or parts of the present invention.Detailed Description

[0036] The following description of diverse embodiments of the present invention is not intended to limit the present invention to any one of these embodiments or corresponding details. Throughout the drawings, same reference signs are used for same components. Terms like "first", "second" etc. are intended to merely name a corresponding component, without defining a certain order or number of components so that, e.g., a component named as first component could also be a second component and vice versa. The terms "comprises", "includes" and / or "has", used in this specification, do not preclude the presence or addition of other elements unless used along with the term "only". The singular forms are intended to include the plural forms as well, unless the context clearly indicates otherwise. Terms regarding orientations, such as "parallel", "perpendicular", "vertical" or the like, should not be construed to only include a strict orientation (such as "strictly parallel" or "strictly perpendicular"), but may also include deviations from such a strict orientation within error margins or tolerances as is customary in the relevant field. Further, the term "at least partially" should be understood to mean "partially or completely / entirely".

[0037] Referring to Figs. 1 to 21, a dryer section assembly (or drying section assembly) 1 according to exemplary embodiments of the present invention is illustrated and will be described in the following.

[0038] The dryer section assembly 1 of the present invention may form part of or configure a dryer section (or drying section) in a papermaking process for paper production. For example, the dryer section assembly 1 may form part or configure a dryer section of a papermaking machine. In a papermaking process, the dryer section with the dryer section assembly 1 may be located upstream a forming section (also called a wet end) and or a press section, in which a paper web is formed from raw material (e.g. a wet fiber suspension) and in which water is partially removed from said paper web as much as possible by means of vacuum suction, pressing / squeezing and or the like. In the papermaking process, the paper web may then be supplied to the dryer section for further removal of water from the paper web and controlled reduction of the moisture content in the paper web. The dryer section with the dryer section assembly 1 may further be located downstream a coating section, a calender section and other postprocessing sections for further tailoring the paper web into the desired final product. The location of the dryer section assembly 1 of the present invention in the papermaking process is however not limited to the above-described layout and may be located at other locations within the papermaking process.

[0039] The dryer section assembly 1 of the present invention may include at least one of a plurality of cylinders 10, a support device 30 and an infrared (IR) device 60. In some exemplary embodiments of the present invention, the dryer section assembly 1 of the present invention may also include a fire detection means 80 and a fire-fighting system 100. In some further exemplary embodiments of the present invention, the dryer section assembly 1 of the present invention may also include a control device 120. However, the dryer section assembly 1 of the present invention is not limited to the illustrated configurations and may include further components or omit some components.

[0040] In the dryer section assembly 1, the plurality of cylinders 10 may for example include various types of cylinders having / performing different functions in the dryer section assembly. For example, the plurality of cylinders 10 may include drying cylinders 12, which define a circumferential contact surface 13 and are configured to guide paper web W at least partially on said circumferential contact surface 13 in a paper conveying direction CD while drying the paper web W by application of heat to the paper web W via said circumferential contact surface 13. The drying cylinders 12 may for example be steam-heated drying cylinders or be otherwise heated as is well-known in the art. The plurality of cylinders 10 may include felt guide cylinder (sometimes also called "felt rollers") 14, which may be configured to support and guide one or more drying felts 15. The drying felts may be configured to support the paper web W and urge the paper web W towards the circumferential contact surface 13 of the drying cylinders 12. Each cylinder of the plurality of cylinders 10 may extend in an elongated manner along a respective cylinder axial direction AD, along which the longitudinal (or rotational) axis of the respective cylinder extends. The paper conveying direction CD may be transverse to said cylinder axial direction AD.

[0041] In an exemplary and non-limiting implementation of the dryer section assembly 1 (see e.g. Fig. 2), the dryer section assembly 1 may be configured as a double-felted dryer section assembly which comprises a first drying felt 15a and a second drying felt 15b as illustrated in the enclosed drawings. The plurality of cylinders 10 may include a plurality of first cylinders 10a and a plurality of second cylinders 10b. The first cylinders 10a may for example be top cylinders, wherein the plurality of second cylinders 10b may be bottom cylinders, located vertically below the top cylinders (e.g. at a lower level as compared to the top cylinders). The first cylinders 10a may be configured to be at least partially wrapped by the first drying felt 15a, and the second cylinders 10b may be configured to be at least partially wrapped by the second drying felt 15b. The first cylinders 10a may include a first drying cylinder 12a and a first felt guide cylinder 14a. The second cylinders 10b may include a second drying cylinder 12b and a second felt guide cylinder 14b. The first felt guide cylinder 14a may be configured to support and guide the first drying felt 15a, and the second felt guide cylinder 14b may be configured to support and guide the second drying felt 15b. Each of the first and second drying cylinders 12a and 12b may be configured to guide the paper web W at least partially on its respective circumferential contact surface in the paper conveying direction WD between its respective circumferential contact surface and the corresponding one of the first and second drying felts 15a and 15b, while drying the paper web W by application of heat to the paper web W via its respective circumferential contact surface.

[0042] The plurality of cylinders 10 of the dryer section assembly 1 may define a cylinder inter-space 16 between at least two adjacent cylinders of the plurality of cylinders 10. The cylinder inter-space 16 may thus form a space or room between two or more cylinder within dryer section assembly 1. For example, in the above implementation of the dryer section assembly 1 as a double-felted dryer section assembly, the cylinder inter-space 16 may be defined at least between the first drying cylinder 12a, the second drying cylinder 12b, the first felt guide cylinder 14a and the second felt guide cylinder 14b. Said cylinder inter-space 16 may also be referred to as a "pocket" in the art. In the cylinder inter-space 16 of dryer section assembly 1, the paper web W may be transferred between different cylinders (e.g. between the first cylinders 10a and the second cylinders 10b) at least partially by a free draw FD in a free draw section and / or a closed draw. For example, in the cylinder inter-space 16 of dryer section assembly 1, the paper web W may move at least substantially linearly (e.g. in a flat plane at least substantially without curvature) along the paper conveying direction WD by a free draw FD from one cylinder to another (i.e. the subsequent) cylinder. A free draw in a free draw section may mean that the paper web W may move or be transferred without being in direct contact (e.g. without being directly guided or supported) with one or more supporting elements, such as a drying felt or one of the plurality of cylinders 10. A closed draw may mean that there is substantially no unsupported draw (or portion) of the paper web in any area of the dryer section assembly or entire dryer section (e.g. that the paper web remains at least partially supported at all times by at least one of the supporting elements, such as a drying felt or one of the plurality of cylinders 10 or the like, during its movement through the dryer section assembly or entire dryer section). Since the cylinder inter-space 16 comprises rather small dimensions and is interposed between and surrounded by various cylinders, regulation and maintenance of appropriate environmental and climatic conditions in said cylinder inter-space 16 is considered important, but may also be complicated and challenging.

[0043] The support device 30 of dryer section assembly 1 may comprise or be configured with a support member 32. The support member 32 may be arranged in said cylinder inter-space 16 and may extend in an elongated manner in said cylinder inter-space 16. For example, the support member 32 may be an elongated beam or a beam-like elongated element. In some exemplary and non-limiting implementations, the support member 32 may form part of or may be configured as a blow doctor device, or the support member 32 may form part of or may be configured as a paper web stabilizer. The use of such a support member 32 in the cylinder inter-space 16 may thus allow to use already present components, such as a beam element of a blow doctor device or a paper web stabilizer, for supporting the IR device 60, thereby providing stable support for the IR device 60 and further components of the present invention and eliminating or at least minimizing the need for additional support elements.

[0044] The dryer section assembly 1 may further comprise a mounting frame 20 for mounting and supporting the plurality of cylinder 10 and the support member 32. mounting frame 20 may be a frame structure made from a plurality of beams and may be fixed to the ground and / or suspended from ceiling of a factory building. The support member 32 may be attached to the mounting frame 20 by means of a mounting bracket 22. The mounting bracket 22 may be configured (e.g. detachable from the mounting frame 20) such that support member 32 may be movable out of cylinder inter-space 16 (e.g. for inspection, maintenance or repair of components attached to the support member 32) along a direction transverse to the paper conveying direction CD (e.g. along a longitudinal direction of the support member housing 40 as described later and / or along the cylinder axial direction AD), thereby providing easy access to the support member 32 and components attached thereto (such as IR modules 62 of IR device 60) for inspection, maintenance and / or repair, thereby reducing maintenance costs and down-time of the dryer section assembly 1. Further, the orientation and position of support member 32 within the cylinder inter-space 16 may be adjustable. For example, the mounting bracket 22 may be configured to rotatably support the support member 32, and dryer section assembly 1 may further comprise an adjustment means 24 configured to allow adjustment of a rotational position of the support member 32 and to maintain said rotational position. However, the support device 30 is not limited thereto, and the orientation and position of support member 32 may also be at a fixed orientation and position within the cylinder inter-space 16.

[0045] The support member 32 may comprise an internal space 34 configured to receive inflowing air and to define an airflow inside the support member 32 as will be described later in further detail. The internal space 34 of the support member 32 may be a dust-proof and / or air-tightly sealed space inside the support member 32. While various exemplary embodiments are described in the following with reference to a support member 32 having the internal space 34, the present invention is however not limited to this exemplary configuration of the support member 32. For example, in case of using one or more (e.g. separate or dedicated) cooling air supply lines (details of which will be described later) for cooling IR modules of IR device 60, a support member according to further exemplary embodiments of the present invention may also be formed without an internal space (e.g. the support member may be formed as an at least substantially solid beam), or the support member may also be formed with an internal space, which may not be configured (e.g. able or allowed) to receive inflowing air and which may thus not define an airflow inside the support member (e.g. the support member may be formed as a hollow beam, without being connected to air supply via air inlet ducts and without defining an airflow inside).

[0046] Referring in more detail to the support member 32, the support member 32 may comprise a support member housing 40 which extends in an elongated manner in said cylinder inter-space 16 along a longitudinal direction of the support member housing 40. The support member housing 40 may be formed as an elongated beam or a beam-like elongated element. For example, in some implementations, the support member housing 40 may extend in said cylinder inter-space 16 in a manner at least substantially parallel to at least some of the cylinders of the plurality of cylinders 10. In other words, the support member housing 40 may be arranged in the cylinder inter-space 16 with its longitudinal axis parallel to the longitudinal (or rotational) axis of the at least some of the cylinders of the plurality of cylinders 10. Specifically, the support member housing 40 may extend at least substantially parallel to the adjacent cylinders defining the cylinder inter-space 16 (e.g. the cylinders located closest to the support member housing 40).

[0047] The support member housing 40 may comprise a plurality of outer wall portions, which at least partially define the support member 32. The plurality of outer wall portions of the support member housing 40 may for example define the internal space 34 of the support member 32. In the embodiment illustrated in the enclosed drawings, the support member housing 40 may have a substantially triangular cross-sectional shape when viewed along the longitudinal direction of the support member housing 40. Accordingly, the triangular cross-sectional shape of the illustrated support member housing 40 may be substantially formed by three outer wall portions 41a, 41b, 41c (e.g. first outer wall portion 41a, second outer wall portion 41b and third outer wall portion 41c) connected into a triangular shape. The outer wall portions may further comprise a first longitudinal end wall portion 41d and a second longitudinal end wall portion (not shown), each longitudinal end wall portion being respectively provided at a corresponding longitudinal end portion of the support member housing 40 and being connected to each of the first outer wall portion 41a, second outer wall portion 41b and third outer wall portion 41c for connecting the first outer wall portion 41a, second outer wall portion 41b and third outer wall portion 41c together. However, the support member housing 40 of the present invention is not limited thereto and other cross-sectional shape with a different number of outer wall portions may be used, e.g. depending on the geometrical shape and dimensions of the cylinder inter-space 16. The support member housing 40 may be formed from metal material, such as steel, stainless steel or other suitable metal or alloy. Accordingly, by means of its structural configuration and the use of metal material, the support member housing 40 may be provided with appropriate rigidity for supporting the various components on or inside the support member housing 40.

[0048] Among the outer wall portions, a first outer wall portion 41a may be arranged so as to face the portion of the paper web W moving through said cylinder inter-space 16. Further, the first outer wall portion 41a may comprise an outer wall opening 44. The outer wall opening 44 may extend in an elongated manner along the longitudinal direction of the support member housing 40. The outer wall opening 44 may be formed continuously or discontinuously (e.g. by a number of windows separate from each other) along the longitudinal direction of the support member housing 40. For example, the outer wall opening 44 may be formed along at least substantially the entire length of the support member housing 40 in the longitudinal direction (e.g. with only small edges of the support member housing 40 defining the longitudinal ends of outer wall opening 44. However, the outer wall opening 44 is not limited thereto and may also formed in a different manner. The support member housing 40 may further comprise an infrared-transmissive wall opening cover 45 (e.g. as illustrated exemplarily in Figs. 6 and 12 to 16), which may be connected to the first outer wall portion 41a and cover the outer wall opening 44 of the first outer wall portion 41a in a dust-proof and / or airtight manner (e.g. to dust-proof and / or air-tightly seal the outer wall opening 44 and thus the internal space 34).

[0049] The support device 30 may further comprise a doctor blade 36 which is configured to remove residual paper material from the circumferential contact surface 13 of a respective one of the plurality of cylinders 10, in particular the drying cylinders 12. The doctor blade 36 may be a mechanical doctor device in the form of a blade or scraper. The doctor blade 36 may be attached to the support member 32. For example, the doctor blade 36 may be attached to an outer wall portion of the support member housing or to an extension portion extending from said outer wall portion. As an example, the first outer wall portion 41a may be configured for attaching the doctor blade 36 thereto, or may include or be connected to an extension portion 42 to which the doctor blade 36 may be attached.

[0050] The support device 30 may further comprise one or more blow openings 38 which are provided in the support member 32. One or more blow openings 38 in the support member 32 are exemplarily illustrated e.g. in Figs. 8 and 12, but may be omitted in other figures for the sake of clarity and without limiting the present invention. In one example, the one or more blow openings 38 may be formed in an outer wall portion (e.g. the first outer wall portion 41a) of the support member 32 so as to face the portion of the paper web W moving through said cylinder inter-space 16. For example, the one or more blow openings 38 may be formed as through-holes, but are not limited in this regard and may also be formed as one or more elongated slots (e.g. extending lengthily along the longitudinal direction of the support member or extending vertically) or the like. The one or more blow openings 38 may allow at least part of air from the airflow inside the internal space 34 of the support member 32 to be branched off. During operation of the dryer section assembly 1, said branched-off air can be discharged from the one or more blow openings 38 and can be directed towards the portion of the paper web W moving through said cylinder inter-space 16. The branched-off air may for example be directed towards a portion of the paper web W upstream (e.g. upstream along the paper conveying direction CD) of said portion of the paper web W irradiated by infrared light (indicated by arrows and reference sign "IL" in Fig. 6) from the IR device 60. To this end, the one or more blow openings 38 may be located in the first outer wall portion 41a above the outer wall opening 44. Additional one or more blow openings may also be provided in an IR device housing 64 which will be described later. Additionally or alternatively to using air branched-off from the airflow inside the internal space 34 of the support member 32, the one or more blow openings may also branch of air supplied by cooling air supply lines 74 which will be described later.

[0051] The support device 30 may further comprise one or more air inlet ducts 46. The one or more air inlet ducts 46 may be which are respectively attached to the support member 32 and in fluid connection with the internal space 34 of the support member 32 so as to introduce air into the internal space 34 of the support member 32. In the enclosed drawings, a single air inlet duct 46 is illustrated and provided at a longitudinal end portion of the support member 32. However, the present invention is not limited thereto, and multiple air inlet ducts 46 may be provided at different positions (e.g. at one or more of the longitudinal end portions of the support member 32, at a central portion of the support member 32 and so on) in different intervals (e.g. evenly distributed along the length of the support member 32, distributed in irregular intervals and so on). As illustrated in the enclosed drawings, the air inlet duct 46 may extend through a respective one (e.g. the second outer wall portion 41b) of the outer wall portions of the outer support member housing 40 into the internal space 34 of the support member 32.

[0052] The dryer section assembly 1 may comprise the infrared (IR) device 60, which may be connected to and supported by the support member 32 and may include a plurality of infrared (IR) modules 62. The IR modules 62 may be configured to emit infrared light towards the portion of the paper web W moving through said cylinder inter-space 16 so as to apply heat to and dry the paper web W moving through said cylinder inter-space 16. In some implementations, the IR modules 62 of the IR device 60 may be configured (e.g. directed such as) to emit infrared light towards at least the paper web W in the free draw section in the cylinder inter-space 16.

[0053] In some exemplary implementations, one, several or all of the IR modules 62 used in the infrared (IR) device 60 of the present invention respectively comprise an infrared-transmissive IR device cover portion (not shown) covering one or more IR emitting units 63 of the respective IR module and being spaced apart from said IR emitting units 63 so as to allow passage of air between the transparent IR device cover portion and the IR emitting units 63. In some exemplary implementations, the IR modules 62 may be provided as a single row extending in an elongated manner in the cylinder inter-space 16 (see Fig. 9) or may be provided in two or more rows stacked one above the other with each row extending in an elongated manner in the cylinder inter-space 16 (see Figs. 10 and 11). The IR modules 62 are however not limited to these implementations and configurations, and various other configurations of IR modules are known in the art and may be used for the IR modules 62.

[0054] The IR modules 62 may be a plurality of electrically-powered IR modules (also simply called "electric IR modules"), which may be configured so as to generate infrared light using electricity. The use of electrically-powered IR modules in the dryer section may additionally improve the drying performance of the dryer section assembly, while offering further operational flexibility. With electrically-powered IR modules, energy from multiple energy sources and in particular renewable sources (such as wind and solar energy) may be flexibly used, thereby allowing to shift consumption of primary energy sources (such as natural gas for the steam-heated drying cylinders, electricity for the IR modules and so on) to the most cost-efficient energy source in a dynamic manner and allowing to reduce ecological footprint. The use of electrically-powered IR modules may thus offer higher flexibility with regard to price differences between different energy sources (such as natural gas prices vs. electricity prices). Further, the use of electrically-powered IR modules may also allow to react to dynamic electricity prices in the energy market (e.g. increasing / shifting electricity consumption in the dryer section at / towards times with lower electricity prices due to an abundance of wind and / or solar energy), thereby further increasing cost-effectiveness. The use of electrically-powered IR modules may further allow to more easily upscale (i.e. increase) drying capacity of a dryer section without significantly changing the overall construction and size of existing dryer sections in papermaking machines, thereby allowing to increase the drying performance without increasing the size and space required for papermaking machines and allowing to reduce costs for retrofitting existing papermaking machines. The IR modules 62 are however not limited to electrically-powered IR modules and other types of IR modules may also be used, wherein only one type of IR modules may be used or multiple types of IR modules may be used in combination.

[0055] Further, the IR modules 62 may be individually controllable or controllable at least in (e.g. discrete / separate) zones, wherein each zone may comprise a subgroup of IR modules 62 among the plurality of IR modules 62. By controlling the IR modules 62 individually or in zones, it is possible to react to non-uniform drying of the paper web W in the dryer section assembly 1. This may allow to improve the drying efficiency and drying performance as well as increase flexibility when drying the paper web W in the dryer section assembly 1 (e.g. allowing spot drying of only certain portions of the paper web W).

[0056] In some exemplary embodiments (e.g. illustrated in Figs. 1 to 8 and 12 to 17 and described in further detail below), the plurality of IR modules 62 may be arranged at least partially inside the support member housing 40 and may be exposed at least partially through the outer wall opening 44 so as to allow to emit infrared light towards the paper web W moving through said cylinder inter-space 16. For example, the IR modules 62 may be arranged completely inside support member housing 40 and covered by (e.g. located behind) the infrared-transmissive wall opening cover 45 so as to be exposed at least partially through the infrared-transmissive wall opening cover 45 covering the outer wall opening 44.

[0057] In other exemplary embodiments (e.g. illustrated in Figs. 18 and 19 and described in further detail below), the IR device 60 comprises an IR device housing 64, which extends in an elongated manner in the cylinder inter-space 16 along a longitudinal direction of the IR device housing 64. The IR device housing 64 may be separate from the support member housing 40 and may be connected to the support member housing 40 via a plurality of support links 68 so as to be supported by the support member housing 40. The IR device housing 64 may be configured to accommodate the IR modules 62 of the IR device 60 in an internal space 66 thereof. The internal space 66 of the IR device housing 64 may be a dust-proof and / or air-tightly sealed space inside the IR device housing 64. The internal space 66 of the IR device housing 64 may be configured to receive inflowing air and to define an airflow inside the IR device housing 64, similar to the internal space 34 of the support member 32. In some implementations (e.g. Figs. 18 and 19), the internal space 66 of the IR device housing 64 may be in fluid-connection with the internal space 34 of the support member 32 so as to receive air from the internal space 34 of the support member 32. In other implementations (e.g. Fig. 20), the dryer section assembly 1 may comprise one or more (e.g. separate or dedicated) cooling air supply lines 74, which are arranged (e.g. installed) at least partially in the cylinder inter-space 16 and separate from the support member 32 and which are connected to the IR device housing 64 so as to be in fluid-connection with the internal space 66 of the IR device housing 64. In this implementation, the internal space 66 of the IR device housing 64 also may not be in fluid-connection with the internal space 34 of the support member 32, but the present invention is not limited in this regard.

[0058] Further, for mounting the IR modules 62, a mounting element 33 may be provided. The mounting element 33 may for example be a plate-like element, e.g. a perforated plate, or a grid-like element or a ladder-like element (e.g. an element with interconnected bars forming a ladder) or may be provided by means of individual bars or beams extending between and connected to the second and third outer wall portions 41b and 41c. In some exemplary embodiments, the support member 32 may comprise the mounting element 33, wherein the mounting element 33 may be arranged inside the internal space 34 of the support member 32 and may be configured for mounting the IR modules thereto (e.g. to the mounting element 33 and thus to the support member 32). In other exemplary embodiments, mounting element 33 may be provided inside the internal space 66 of the IR device housing 64 and may be configured for mounting the IR modules thereto (e.g. to the mounting element 33 and thus to the IR device housing 64).

[0059] In order to provide cooling to the IR modules 62 and / or to reduce or eliminate dust accumulation on the IR modules 62, the IR device 60 is configured to guide (and blow) air towards the IR modules 62 and to cool the IR modules 62 in a convective manner, for example by means of the airflow inside the support member 32 and / or by means of air supplied by one or more cooling air supply lines 74. The dryer section assembly 1 may comprise or utilize various configurations (either alone or in combination) for guiding air towards the IR modules 62 and cooling the IR modules 62 via said guided air. The air used for convective cooling of the IR modules 62 may be pre-conditioned to a predetermined temperature and / or predetermined humidity before being supplied to the IR modules 62.

[0060] In some exemplary embodiments (see for example Figs. 6 and 12 to 17), the support member 32 may comprise air guiding means 50 which is arranged inside the support member housing 40. The air guiding means 50 may at least partially define an air passageway 52 configured to allow air to pass therethrough to provide convective cooling to the IR modules 62. In an example, the plurality of IR modules 62 may be for example arranged at least partially inside the support member housing 32 between the first outer wall portion 41a and the air guiding means 50. The air passageway 52 may guide air through an inside and / or along an outer surface of the IR modules 62 for cooling. While passing and cooling the IR modules 62, the air may absorb heat from the IR modules 62 and increase in temperature (i.e. heat up). Further, the air passing the IR modules 62 may also blow off and / or remove (e.g. carry away) dust from residual paper material and thus avoid dust accumulations. The heated air (after having passed and cooled the IR modules 62) may then be discharged to the cylinder inter-space 16 and / or be discharged from the internal space 34 of the support member 38 so as to be guided out of the dryer section assembly 1 (e.g. without entering the cylinder inter-space 16).

[0061] In case of the heated air being discharged to the cylinder inter-space 16, said heated air may be used to dry and / or ventilate the paper web W moving through said cylinder inter-space 16. In other words, the heated air being discharged to the cylinder inter-space 16 may provide a blow functionality similar to blow doctor devices by ventilating the paper web W in the cylinder inter-space 16 so as to improve temperature and / or humidity management in the cylinder inter-space 16. Such heated air discharged to the cylinder inter-space 16 may also act as an air cushion or air curtain against intrusion of dust, and may thus avoid or eliminate intrusion of dust and dust accumulations.

[0062] In case of the heated air being discharged and guided out of the dryer section assembly 1, said heated air may be used directly in other process steps and / or may be supplied to a heat exchanging device (not shown) so as to recover heat from the heated air for use in other process steps and to re-supply the cooled air to the support member 32 in the dryer section assembly 1 according to the present invention. Further, dust may be removed (e.g. carried away) by the heated air being discharged and guided out of the dryer section assembly 1 and might be filtered out by a downstream filtering device (not shown) or otherwise removed from the discharged heated air.

[0063] With particular reference to Figs. 12 and 13, in the case of the heated air being discharged to the cylinder inter-space 16, the air passageway 52 in the support member 32 may guide the air through an inside and / or along an outer surface of the IR modules 62 for cooling and may then discharge the air having passed and cooled the IR modules 62 from the support member 32 towards the portion of the paper web W moving through said cylinder inter-space 16, e.g. through the one or more blow openings 38 provided in the support member 32. The heated air (after having cooled the IR modules 62) may be discharged towards the portion of the paper web W moving through said cylinder inter-space 16 (e.g. thereby providing the blow functionality similar to blow doctor devices). In this regard, the heated air may for example be directed towards a portion of the paper web W upstream (e.g. upstream along the paper conveying direction CD) of said portion of the paper web W irradiated by infrared light from the IR device 60.

[0064] With particular reference to Figs. 14 and 15, in the case of the heated air being discharged and guided out of the dryer section assembly 1, the air passageway 52 in the support member 32 may guide the air through an inside and / or along an outer surface of the IR modules 62 for cooling and may then discharge the air having passed and cooled the IR modules 62 from the internal space 34 of the support member 32 and out of the dryer section assembly 1. To this end, the support member 32 may comprise one or more air discharge ducts 48, which are in fluid-connection with the internal space 34 of the support member 32 and are configured to guide the heated air out of the dryer section assembly 1. For example, the one or more air discharge ducts 48 may respectively be attached to one or more outer wall portions of the plurality of outer wall portions of the support member housing 40 (such as, but not limited to, first longitudinal end wall portion 41d). The one or more air discharge ducts 48 may respectively be in fluid connection with the internal space 34 of the support member 32 so as to receive the heated air discharged from the internal space 34 of the support member 32. The one or more air discharge ducts 48 may then respectively guide the heated air out of the dryer section assembly 1. In this configuration, the support member 32 may not be provided with one or more blow openings 38.

[0065] In an exemplary variation of the configuration shown in Figs. 14 and 15, one or more blow openings 38 may additionally be provided in the support member 32, and the dryer section assembly 1 further comprise a (e.g. separate or dedicated) blow air supply dedicated for providing separate blow air, wherein the separate blow air supply may be in fluid-connection (e.g. by separate lines, pipes and / or hoses) with the one or more blow openings 38. In other words, in this variation, the one or more blow openings 38 may receive dedicated blow air from a separate air supply and discharge said dedicated blow air from the support member 32 towards the portion of the paper web W moving through said cylinder inter-space 16, whereas the IR modules 62 may receive dedicated cooling air via the air inlet duct 46 and heated air, which is dedicated cooling air after having cooled the IR modules 62, may be discharged and guided out of the dryer section assembly 1 via the one or more air discharge ducts 48 (i.e. in the manner as illustrated in Figs. 14 and 15).

[0066] Further, with particular reference to Figs. 16 and 17, the dryer section assembly 1 of the present invention may also adopt a configuration in which heated air is both, at least in part discharged to the cylinder inter-space 16 and at least in part discharged and guided out of the dryer section assembly 1.

[0067] In other exemplary embodiments (see for example Figs. 18 and 19), the internal space 66 of the IR device housing 64 may be in fluid-connection with the internal space 34 of the support member 32 via an internal channel 70 of at least one of the support links 68 so as to allow air to flow from the support member 32 to the IR device housing 64 for convective cooling the IR modules 62 located inside the IR device housing 64. The heated air in the IR device housing 64 may then be discharged to the cylinder inter-space 16 and / or discharged and guided out of the dryer section assembly 1, e.g. by discharging the heated through additional more blow openings in the IR device housing 64 or by guiding the heated air back to the support member 32 and out of the support member 32 as described hereinabove. Further, the support member 32 may also optionally include one or more blow openings for blowing air 72 into the cylinder inter-space 16, e.g. towards the portion of the paper web W moving through the cylinder inter-space 16.

[0068] In yet further exemplary embodiments (see for example Fig. 20), one or more cooling air supply lines 74 may be in fluid-connection with the internal space 66 of the IR device housing 64 so as to supply cooling air into the internal space 66 of the IR device housing 64 for convective cooling the IR modules 62 located inside the IR device housing 64. The cooling air supply lines 74 may be provided separate from the support member 32. The cooling air supply lines 74 may form the only supply of cooling air into internal space 66 of the IR device housing 64, but the present invention is not limited thereto. The heated air (after having absorbed heat from and cooled the IR modules 62) may then be discharged to the cylinder inter-space 16 (e.g. by one or more blow openings in the IR device housing 64) and / or discharged and guided out of the dryer section assembly 1 as described with reference to Figs. 18 and 19 above. Additionally or alternatively, a separate air discharge line (not shown) may be connected to the IR device housing 64 in fluid-connection with the internal space 66 of the IR device housing 64, and heated air may be discharged and guided out of the dryer section assembly 1 via the separate air discharge line connected to the IR device housing 64, in a similar manner as described for the one or more air discharge ducts 48.

[0069] Referring to Fig 21, the dryer section assembly 1 according to some exemplary embodiments of the present invention may also include a fire detection means 80 and a fire-fighting system 100.

[0070] The fire detection means 80 may be arranged on or inside of at least one of the support device 30 and IR device 60. More specifically, the fire detection means 80 may be arranged on or inside the support member 32 and / or the IR device housing 64, depending on the configuration of the support device 30 and IR device 60. In Fig. 21, the fire detection means 80 is exemplarily illustrated as being provided in the support device 30, but the present invention is not limited thereto. The fire detection means 80 may be configured to detect a fire and to provide a notification of a fire. The notification may be an electric signal, a wireless signal, a message transferred (e.g. encoded and transmitted) by use of a communication protocol or the like. For example, the fire detection means 80 may be a smoke detection sensor, a heat detections sensor or other type of fire detection sensor suitable for the environmental and climatic conditions in the dryer section assembly 1.

[0071] The fire-fighting system 100 may be in fluid connection with the support device 30 and the IR device 60. More specifically, the fire-fighting system 100 may be in fluid connection with the internal space 34 of the support member 32 and / or the internal space 66 of IR device housing 64, depending on the configuration of the support device 30 and the IR device 60. The fire-fighting system 100 may be configured to introduce fire-extinguishing and / or fire-retarding gas (also referred to as fire-fighting gas) into the support device 30 and the IR device 60 upon notification of a fire from the fire detection means 80. To this end, the fire-fighting system 100 may be communicatively coupled to the fire detection means 80 in a wired manner and / or wireless manner. The fire-fighting system 100 may for example be coupled to a gas supply line and / or comprise a gas reservoir (commonly referred to by reference sign 102) and introduce fire-extinguishing and / or fire-retarding gas into the one or more air inlet ducts 46, directly into the support member housing 40 and / or directly into the IR device housing 64. In Fig. 21, the example of introducing the fire-extinguishing and / or fire-retarding gas into the air inlet duct 46 of the support device 30 is exemplarily illustrated, but the present invention is not limited thereto. Examples for fire-extinguishing and / or fire-retarding gas may include nitrogen, carbon dioxide or any other appropriate gas.

[0072] The application of the fire detection means 80 and a fire-fighting system 100 in the dryer section assembly 1 according to the present invention allows to detect and extinguish a potential fire hazard and to further reduce the risk of a fire outbreak and fire-related damages to the dryer section assembly 1 and other equipment used in the papermaking process.

[0073] Referring again to Fig. 21, the dryer section assembly 1 according to some further exemplary embodiments of the present invention may also include a control device 120, which may be operatively (e.g. communicatively and / or electrically) coupled in a wired manner and / or wireless manner to various components of the dryer section assembly 1, such as the IR device 60 and / or the fire-fighting system 100. The control device 120 may include a processing unit, e.g. a microcontroller, a microprocessor, and the like, that processes various signals and executes commands. The control device 120 may be configured to control the operation of the various components of the dryer section assembly 1. For example, the control device 120 may be configured to control the operation of the IR modules 62 of the IR device 60 and / or to control the flow rate (amount) of air supplied for cooling the IR modules 62. As an example, the control device 120 may be configured to control an irradiation intensity of the IR modules 62 or may turn the IR modules 62 on / off. Accordingly, the control device 120 may be configured to reduce the irradiation intensity of the IR modules 62 or control the IR modules 62 to be turned off upon detection of a web break. Alternatively or additionally, control device 120 may be configured increase the flow rate (amount) of air supplied for increased cooling the IR modules 62 upon detection of the web break. Techniques for detecting of a web break are well known to the skilled person in the art and will thus not be described in further detail. The detection of a web break may be communicated to the control device 120 from external devices configured to detect the web break, or the web break may be detected by the control device 120 itself, e.g. based on incoming sensor signals. Accordingly, turning off the IR modules 62 and / or increasing the cooling of the IR modules 62 by the control device 120 upon detection of the web break may minimize the risk of a fire outbreak.

[0074] In the following, it is referred again in further detail to Figs. 12 to 20 for explaining exemplary embodiments of dryer section assembly 1, which illustrate different ways of providing convective air cooling to the IR modules 62 and the respective operating principles. These exemplary embodiments may at least in part comprise or adopt the above-described components of dryer section assembly 1 (as indicated by the same reference signs), and thus a repeated description will be omitted and it is instead referred to the above description of said components.

[0075] Referring now in more detail to Figs. 12 and 13, an exemplary embodiment is illustrated and described, in which the heated air after having passed and cooled the IR modules 62 is discharged to the cylinder inter-space 16. In this exemplary embodiment, guiding means 50 comprises an internal guide wall 54. The internal guide wall 54 may extend between a first end portion 54a and a second end portion 54b, wherein the first end portion 54a and the second end portion 54b are connected via a bent portion 54c. The bent portion 54c may define an acute angle between the first end portion 54a and the second end portion 54b, thereby defining a triangle-like cross-sectional shape of the internal guide wall 54 when viewed along the longitudinal direction of the support member housing 40. The internal guide wall 54 is connected to the support member housing 40 at the first end portion 54a of the internal guide wall 54. The internal guide wall 54 defines an air distribution chamber 56 inside the support member 32 (e.g. inside the internal space 34 of the support member 32). More specifically, the air distribution chamber 56 may be defined between the internal guide wall 54 and the third outer wall portion 41c of the support member housing 40. The air distribution chamber 56 may extend (e.g. partially or completely) along the longitudinal direction of the support member housing 40. The air inlet duct 46 may be connected to the internal guide wall 54 of the air guiding means 50 and open into the air distribution chamber 56 so as to allow air to be supplied and introduced from the air inlet duct 46 into the air distribution chamber 56.

[0076] The internal guide wall 54 further defines an air passage opening 58 between the second end portion 54b of the internal guide wall 54 and the support member housing 40. The air passage opening 58 is configured to allow air to be discharged from the air distribution chamber 56 towards the first outer wall portion 41a and the IR modules 62, i.e. towards the air passageway 52 defined between the first outer wall portion 41a and the IR modules 62. In other words, the air passage opening 58 may form an opening between the second end portion 54b of the internal guide wall 54 and the third outer wall portion 41c of the support member housing 40, through which air may flow from the air distribution chamber 56 to the air passageway 52. For example, the air passage opening 58 may be an elongated slot extending along the longitudinal direction of the support member housing 40. The air passageway 52 then guides the air through an inside and / or along an outer surface of the IR modules 62 for cooling. Similar to the air distribution chamber 56, the air passageway 52 may extend (e.g. partially or completely) along the longitudinal direction of the support member housing 40.

[0077] By the above configuration, the internal guide wall and the support member housing 40 may define the airflow inside the support member used for cooling the IR modules 62 in a convective manner. As indicated by the arrows (representing the airflow inside the support member) in Figs. 12 and 13, relatively cool air (having a relatively low temperature T1) is introduced by the air inlet duct 46 into the air distribution chamber 56 and is distributed in the air distribution chamber 56 along the longitudinal direction of the support member housing 40. This way, the relatively cool air may be appropriately distributed so as to be supplied to each of the IR modules 62 for cooling. The relatively cool air then passes through the air passage opening 58 and enters the air passageway 52. The air guided in the air passageway 52 passes through an inside and / or along an outer surface of the IR modules 62 while absorbing heat from and thus cooling the IR modules 62 in a convective manner. The air thus increases in temperature while passing through the air passageway 52 and is then discharged from the air passageway 52 of the support member 32 through the one or more blow openings 38 towards the portion of the paper web W moving through the cylinder inter-space 16.

[0078] The air discharged from the one or more blow openings 38 may have a relatively high temperature T2. As an example, the air of relatively low temperature T1, which is introduced by the air inlet duct 46, may have a temperature in the range of about 30°C to about 70°C (for example 50°C), whereas the air of relatively high temperature T2, which has absorbed heat from and cooled the IR modules 62, may have a temperature in the range of about 110°C to about 150°C (for example 130°C). It is to be understood that these temperatures are only exemplary and that the actual temperatures may depend on the actual use case and application, e.g. the preconditioning of the air introduced by the air inlet duct 46 and the actual heat generation (in turn depending e.g. on the emission intensity) of the IR modules 62. In this embodiment, the heated air discharged from the one or more blow openings 38 is further directed towards a portion of the paper web W upstream (e.g. upstream along the paper conveying direction CD) of said portion of the paper web W irradiated by infrared light from the IR modules 62.

[0079] Referring now in more detail to Figs. 14 and 15, a further exemplary embodiment is illustrated and described, in which the heated air after having passed and cooled the IR modules 62 is discharged from the internal space 34 of the support member 38 so as to be guided out of the dryer section assembly 1 (e.g. without entering the cylinder inter-space 16). The exemplary embodiment of Figs. 14 and 15 for example differs from the previous above-described exemplary embodiment of Figs. 12 and 13 in that the one or more blow openings 38 are omitted or not provided in the support member 32. On the other hand, the above-described air discharge duct 48 is provided in the exemplary embodiment of Figs. 14 and 15.

[0080] As indicated by the arrows (representing the airflow inside the support member) in Figs. 14 and 15, relatively cool air (having the relatively low temperature T1) is introduced by the air inlet duct 46 into the air distribution chamber 56 and is distributed in the air distribution chamber 56 along the longitudinal direction of the support member housing 40. The relatively cool air passes through the air passage opening 58 and enters the air passageway 52, where it passes through an inside and / or along an outer surface of the IR modules 62 while absorbing heat from and thus cooling the IR modules 62 in a convective manner. The heated air having the relatively high temperature T2 after absorbing heat from and cooling the IR modules 62 is then guided by the air passageway 52 towards the air discharge duct 48 and is then out of the dryer section assembly 1 through the air discharge duct 48 and may be re-used subsequently used otherwise as described above. Temperature T1 and T2 may be identical or similar to those described above with reference to Figs. 12 and 13.

[0081] In yet a further exemplary embodiment, a variation of Figs. 14 and 15 as described above may also be provided, in which one or more blow openings 38 may also be provided in the support member 32 (similar to Figs. 12 and 13) and may receive dedicated blow air from a separate blow air supply. The one or more blow openings 38 may then discharge said dedicated blow air from the support member 32 towards the portion of the paper web W moving through said cylinder inter-space 16. On the other, the IR modules 62 may receive dedicated cooling air via the air inlet duct 46. The dedicated cooling air may also be distributed by air distribution chamber 56, may pass through air passage opening 58 and enter the air passageway 52, where it passes through an inside and / or along an outer surface of the IR modules 62 while absorbing heat from and thus cooling the IR modules 62 in a convective manner. The heated air may then be discharged and guided out of the dryer section assembly 1 via the one or more air discharge ducts 48 in the manner as illustrated in Figs. 14 and 15.

[0082] Referring now in more detail to Figs. 16 and 17, yet a further exemplary embodiment is illustrated and described, in which the exemplary embodiments of Figs. 12 and 13 and of Figs. 14 and 15 are combined with each other. That is, in the exemplary embodiment of Figs. 16 and 17, the heated air after having passed and cooled the IR modules 62 is (1) in part discharged from the internal space 34 of the support member 38 through the air discharge duct 48 so as to be guided out of the dryer section assembly 1 and (2) in part discharged through the one or more blow openings 38 towards the portion of the paper web W moving through the cylinder inter-space 16. In other words, at least part of the heated air is branched off and said branched-off air is discharged from the one or more blow openings 38 and directed towards the portion of the paper web W moving through said cylinder inter-space 16, while the remaining part of the heated air is discharged from the internal space 34 of the support member 38 through the air discharge duct 48 so as to be guided out of the dryer section assembly 1. Temperature T1 and T2 may be identical or similar to those described above with reference to Figs. 12 to 15.

[0083] Referring now in more detail to Figs. 18 and 19, still a further exemplary embodiment is illustrated and described, in which the IR device 60 comprises a separate IR device housing 64 for accommodating the IR modules 62, wherein the IR device housing 64 is connected to the support member housing 40 via a plurality of support links 68 having internal channels 70. Further, the support member 32 of the exemplary embodiment of Figs. 18 and 19 may include one or more blow openings (not shown, but identical or similar to blow openings 38 as described above) for blowing air 72 into the cylinder inter-space 16, e.g. towards the portion of the paper web W moving through the cylinder inter-space 16. In other words, the support device 30 of the exemplary embodiment of Figs. 18 and 19 may function as a blow doctor device by means of the doctor blade 36 and the blow openings in the support member 32.

[0084] The plurality of support links 68 are connected with one end thereof to the support member housing 40 and are connected with the other end thereof to the IR device housing 64. The support links 68 may be provided on both opposite longitudinal end portions of each of the support member housing 40 and the IR device housing 64 (wherein only the configuration of support links 68 on one longitudinal end portion is exemplarily illustrated in the view of Figs. 18 and 19). In other words, a first set of support links 68 may be provided at a first longitudinal end portion of each of the support member housing 40 and the IR device housing 64, wherein a second set of support links 68 may be provided at a second longitudinal end portion of each of the support member housing 40 and the IR device housing 64, the first longitudinal end portion and the second longitudinal end portion being opposite to each other. The plurality of support links 68 hingedly connect the support member housing 40 and the IR device housing 64 with each other. In other words, the support links 68 may be pivotably connected to both of the support member housing 40 and the IR device housing 64. By means of the hinge connection between the support member housing 40 and the IR device housing 64, the IR device housing 64 is pivotable between a first pivotal position (as illustrated in Fig. 18), in which the IR device housing 64 is positioned away from the paper web W moving through the cylinder inter-space 16 and is positioned closer to the support member housing 40, and a second pivotal position (as illustrated in Fig. 19), in which the IR device housing 64 is positioned closer to the paper web W moving through said cylinder inter-space 16 and is positioned away from the support member housing 40. The IR device housing 64 may be pivotable to any position between the first pivotal position and second pivotal position. The IR device housing 64 may be arranged (e.g. orientated and / or aligned) at least substantially parallel to the paper web W moving through said cylinder inter-space 16.

[0085] In the illustrated exemplary embodiment, each of the support links 68 comprises an internal channel 70 which is in fluid connection with both the internal space 34 of the support member 32 and the internal space 66 of the IR device housing 64 so as to allow air to flow from the support member 32 to the IR device housing 64 for convective cooling the IR modules 62 located inside the IR device housing 64. In other words, air from the airflow inside the support member 32 may be used (e.g. branched off) and directed into the IR device housing 64 for cooling the IR modules 62 located therein in a convective manner.

[0086] For example, relatively cool air may flow through the internal channels 70 of support links 68 located at one longitudinal end portion (e.g. through the internal channels 70 of the first set of support links 68) from the internal space 34 of the support member 32 into the internal space 66 of the IR device housing 64. Said relatively cool air may then pass through the internal space 66 of the IR device housing 64 while absorbing heat from and cooling the IR modules 62, thereby increasing in temperature. The heated air after absorbing heat from and cooling the IR modules 62 may be discharged and guided may then flow through the internal channels 70 of support links 68 located at the other longitudinal end portion (e.g. through the internal channels 70 of the second set of support links 68) from the internal space 66 of the IR device housing 64 into the internal space 34 of the support member 32. The heated air flowing into the internal space 34 of the support member 32 may then be discharged and guided out of the dryer section assembly 1, e.g. by means of air discharge duct 48 as described herein-above.

[0087] In further exemplary embodiments, the IR device housing 64 of Figs. 18 and 19 may additionally include one or more blow openings which are arranged so as to face the portion of the paper web W moving through said cylinder inter-space 16. The one or more blow openings provided in the IR device housing 64 may allow at least part of heated air inside the internal space 66 of the IR device housing 64 to be discharged from the one or more blow openings provided in the IR device housing 64 and to be directed towards the portion of the paper web W moving through said cylinder inter-space 16, while a remaining part of the heated air inside internal space 66 of the IR device housing 64 may flow into the internal space 34 of the support member 32 and may then be discharged and guided out of the dryer section assembly 1.

[0088] In another exemplar embodiment, the IR device housing 64 of Figs. 18 and 19 may include the one or more blow openings provided in the IR device housing 64 as described above, but may not include internal channels 70 for flowing heated air from the IR device housing 64 into the internal space 34 of the support member 32. Hence, the heated air may only be discharged from IR device housing 64 via the one or more blow openings provided in the IR device housing 64, similar to the embodiment described with reference to Figs. 12 and 13.

[0089] Referring now in more detail to Fig. 20, still a further exemplary embodiment is illustrated and described, in which the IR device 60 comprises a separate IR device housing 64 for accommodating the IR modules 62, wherein the dryer section assembly 1 comprises a (e.g. separate or dedicated) cooling air supply line 74, which extend at least partially through the cylinder inter-space 16 and are provided separate from the support member 32. The cooling air supply line 74 are dedicated for providing cooling air to the IR modules 62 in the IR device housing 64. To this end, cooling air supply line 74 (e.g. one end of the cooling air supply line 74) are on the one hand connected to the IR device housing 64 so as to be in fluid-connection with the internal space 66 of the IR device housing 64. On the other hand, the cooling air supply line 74 (e.g. another end of the cooling air supply line 74) may be connected to a source of cooling air, such as an air conditioning device or heat exchanger external to the dryer section assembly 1. In the exemplary embodiment of Fig. 20, the cooling air supply line 74 forms the only supply of cooling air for the IR modules 62 in the IR device housing 64 and no internal channels 70 are provided in the support links 68. In variations of the exemplary embodiment of Fig. 20, the support member 32 may also be a support member without an internal space 34 as described above (wherein in such a case the one or more blow openings for blowing air 72 may be omitted). The present invention is however not limited to the particular configuration illustrated in Fig. 20, and in further embodiments both, the cooling air supply line 74 and internal channels 70, may be simultaneously provided to supply cooling air to the IR modules 62 in the IR device housing 64. Further, the cooling air supply line 74 may also be (e.g. fluidly) connected to the fire-fighting system 100 so as to allow the introduction of fire-extinguishing and / or fire-retarding gas into the IR device housing 64 via the cooling air supply line 74 upon notification of a fire as described herein above. In case that the IR device housing 64 is pivotable between the first pivotal position and second pivotal position (as illustrated by Figs. 18 and 19 in principle), the cooling air supply line 74 may be flexible (e.g. a flexible and / or corrugated pipe or flexible hose or the like) so as to adapt to the change of position and orientation of the IR device housing 64 between the first pivotal position and second pivotal position.

[0090] Following the above descriptions of the dryer section assembly 1 according to the present invention, the present invention further relates to the usage of an IR device 60 for drying a paper web in a cylinder inter-space 16 between at least two cylinders of the plurality of cylinders 10 of a dryer section assembly 1 during paper production. When the IR device 60 is used for drying a paper web in the cylinder inter-space 16, the IR modules 62 of the IR device 60 are cooled by air, which flows in the internal space 34 of the support member 32 and is guided to the IR modules 62 for convective cooling of the IR modules 62, and / or air, which is supplied by one or more cooling air supply lines 74 of the dryer section assembly 1, which are in fluid connection with the IR modules 62 and provided separate from the support member 32.

[0091] With reference to Fig. 22, a method 200 of drying a paper web in a dryer section assembly during paper production according to an embodiment of the present invention is provided. The dryer section assembly may be a dryer section assembly (e.g. dryer section assembly 1) according to embodiments of the present invention. Furthermore, the below described method steps may be performed subsequent to each other or parallel to each other. At least some of the below described method steps may be performed under the control of or by interaction with the control device 120 described above.

[0092] The method 200 includes the steps of: arranging (S210) the support device 30 and the infrared (IR) device 60 with IR modules 62 in the cylinder inter-space 16 between at least two adjacent cylinders of the plurality of cylinders 10, air-cooling (S220) the IR modules 62 of the IR device 60, drying and / or ventilating (S230) the paper web W moving through the cylinder inter-space 16 by at least one of (a) emitting infrared light by means of the air-cooled IR modules 62 towards the paper web W moving through the cylinder inter-space 16 and (b) blowing air from the support device 30 towards the paper web W moving through the cylinder inter-space 30.

[0093] The step S220 of air-cooling the IR modules 62 of the IR device 60 may further include that the air blown towards the paper web W corresponds to or at least partially includes the air heated during air-cooling the IR modules 62 of the IR device 60.

[0094] The step S220 of air-cooling the IR modules 62 of the IR device 60 may additionally or alternatively include that air heated during air-cooling the IR modules 62 of the IR device 60 is discharged and guided out of the dryer section assembly 1 (e.g. without entering the cylinder inter-space 16, in particular without being blown towards the paper web W).

[0095] The method 200 may further include directing the air blown from the support device 30 towards a portion of the paper web W upstream the portion of the paper web W irradiated by infrared light from the plurality of IR modules.

[0096] The method 200 may further include, when the dryer section assembly includes an IR device housing 64 separate from and rotatably connected to the support member housing 40 of the support device 30 and accommodating the IR modules 62, pivoting the IR device housing 64 between a first pivotal position, in which the IR device housing 64 is positioned away from the paper web W moving through the cylinder inter-space 16 and is positioned closer to the support member housing 40, and a second pivotal position, in which the IR device housing 64 is positioned closer to the paper web W moving through the cylinder inter-space 16 and is positioned away from the support member housing 40.

[0097] The method 200 may further include detecting (e.g. by the control device 120) a web break, and controlling (e.g. by the control device 120) an irradiation intensity of the IR modules 62 to be reduced or controlling the IR modules 62 to be turned on / off.

[0098] The method 200 may further include detecting, by the fire detection means 80, a fire, providing, by the fire detection means 80, a notification of a fire, and, when the fire-fighting system 100 receives the notification of a fire from the fire detection means 80, introducing a fire-extinguishing and / or fire-retarding gas into the support device 30 and the IR device 60.

[0099] Accordingly, the present invention provides a dryer section assembly for drying a paper web, usage of an infrared device for drying a paper web in a dryer section assembly and a method of drying a paper web in a dryer section assembly during paper production according to the above-described embodiments of the present invention, which may provide at least some or all of the technical effects and advantages described in relation to the present invention.

[0100] The present invention has been described above in detail with reference to detailed embodiments thereof. It will be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles of the present invention, the scope of which is defined in the appended claims. Accordingly, the detailed description of the present invention is not intended to limit the present invention to the disclosed embodiments.

Claims

1. Dryer section assembly (1) for drying a paper web (W) during paper production, the dryer section assembly (1) comprising: a plurality of cylinders (12), wherein at least some cylinders of the plurality of cylinders are configured as drying cylinders (12), which define a circumferential contact surface (13) and are configured to guide the paper web (W) at least partially on said circumferential contact surface (13) in a paper conveying direction (CD) while drying the paper web (W) by application of heat to the paper web (W) via said circumferential contact surface (13), wherein the plurality of cylinders (10) defines a cylinder inter-space (16) between at least two adjacent cylinders of the plurality of cylinders (10), a support device (30) comprising a support member (32) which is arranged in said cylinder inter-space (16) and extends in an elongated manner in said cylinder inter-space (16), an infrared (IR) device (60) connected to and supported by the support member (32) and comprising a plurality of IR modules (62), optionally a plurality of electrically-powered IR modules, which are configured to emit infrared light towards a portion of said paper web (W) moving through said cylinder inter-space (16), wherein the IR device (60) is configured to cool the IR modules (62) by means of air in a convective manner.

2. Dryer section assembly (1) of claim 1, wherein: the support member (32) comprises an internal space (34) configured to receive inflowing air and to define an airflow inside the support member (32), and the IR device (60) is configured to cool the IR modules (62) in a convective manner by means of air provided from the airflow inside the support member (32), and / or the IR device (60) is configured to cool the IR modules (62) in a convective manner by means of air supplied by one or more cooling air supply lines (74) which are comprised in the dryer section assembly (1) and are in fluid connection with the IR modules (62) and provided separate from the support member (32).

3. Dryer section assembly (1) of claim 1 or 2, wherein the support device further comprises a doctor blade (36) which is configured to remove residual paper material from the circumferential contact surface (13) of a respective one of the plurality of cylinders 10, and / or one or more blow openings (38) which are provided in the support member (32), wherein the support device (30) is configured so as to allow at least part of air from the airflow inside the support member (32) to be branched off via the one or more blow openings (38), wherein the one or more blow openings (38) are arranged so as to face the portion of the paper web (W) moving through said cylinder inter-space (16), whereby said branched-off air is directed towards the portion of the paper web (W) moving through said cylinder inter-space (16), wherein the branched-off air is optionally directed towards a portion of the paper web (W) upstream said portion of the paper web (W) irradiated by infrared light from the plurality of IR modules (62).

4. Dryer section assembly (1) of any one of claims 1 to 3, wherein the support member (32) comprises: a support member housing (40) which extends in an elongated manner in said cylinder inter-space (16) along a longitudinal direction of the support member housing (40), the support member housing (40) comprising a plurality of outer wall portions (41a-41d) which at least partially define the support member (32), optionally the internal space (34) of the support member (32), and wherein, optionally, the support member housing (40) has a substantially triangular cross-sectional shape when viewed along the longitudinal direction of the support member housing (40).

5. Dryer section assembly (1) of claim 4, wherein the support member housing (40) comprises a first outer wall portion (41a) of the plurality of outer wall portion, the first outer wall portion (41a) being arranged so as to face the portion of the paper web (W) moving through said cylinder inter-space (16), wherein the first outer wall portion (41a) comprises an outer wall opening (44), and the plurality of IR modules (62) are arranged at least partially inside the support member housing (40) and are exposed at least partially through said outer wall opening (44) so as to allow to emit infrared light towards the paper web (W) moving through said cylinder inter-space (16), wherein, optionally, the doctor blade (36) of claim 2 is attached to said first outer wall portion (41a) of the support member housing (40), optionally by means of an extension portion (42) extending from said first outer wall portion (41a), wherein, further optionally, the support member housing (40) comprises an infrared-transmissive wall opening cover (45) which is connected to the first outer wall portion (41a) and covers the outer wall opening (44) of the first outer wall portion (41a) in in a dust-proof and / or airtight manner.

6. Dryer section assembly (1) of claim 5, wherein the support member (32) comprises an air guiding means (50) which is arranged inside the support member housing (40) and at least partially defines the airflow inside the support member (32), wherein the air guiding means (50) at least partially defines an air passageway (52) configured to allow air to pass therethrough to provide convective cooling to the IR modules (62), wherein the plurality of IR modules (62) are arranged at least partially inside the support member housing (40) between the first outer wall portion (41a) and the air guiding means (50), wherein, optionally, the support member (32) further comprises a mounting element (33) arranged inside the internal space (34) of support member (32) and configured for mounting the IR modules (62) thereto.

7. Dryer section assembly (1) of claim 6, wherein the air guiding means (50) comprises an internal guide wall (54) connected to the support member housing (40) at a first end portion (54a) of the internal guide wall (54), wherein the internal guide wall (54) defines an air distribution chamber (56) inside the support member (32), optionally inside the internal space (34) of the support member (32), said air distribution chamber (56) extending along the longitudinal direction of the support member housing (40), wherein the internal guide wall (54) further defines an air passage opening (58) between a second end portion (54b) of the internal guide wall (54) and the support member housing (40), the air passage opening (58) being configured to allow air to be discharged from the air distribution chamber (56) towards the first outer wall portion (41a) and the IR modules (62), wherein the first outer wall portion (41a) and the IR modules (62) define the air passageway (52) configured to allow air, which has passed through the air passage opening (58), to pass therethrough to provide convective cooling to the IR modules (62).

8. Dryer section assembly (1) according to any one of claims 1 to 7, wherein the support member (32) is further configured to discharge air having cooled the IR modules (62) to the cylinder inter-space (16), optionally towards the portion of the paper web (W) moving through said cylinder inter-space (16).

9. Dryer section assembly (1) of claim 8 in combination with claim 6 or 7, wherein, in the support member (32), the air passageway (52) is further configured to guide air through an inside and / or along an outer surface of the IR modules (62) for cooling and to discharge the air having passed and cooled the IR modules (62) from the support member (32) towards the portion of the paper web (W) moving through said cylinder inter-space (16), optionally through the one or more blow (38) openings of claim 2, wherein, further optionally, one, several or all of the IR modules (62) respectively comprise an infrared-transmissive IR device cover portion covering one or more IR emitting units (63) of the respective IR module (62) and being spaced apart from said IR emitting units (63) so as to allow passage of air between the transparent IR device cover portion and the IR emitting units (63).

10. Dryer section assembly (1) according to any one of claims 1 to 9 in combination with the internal space (34) of claim 2, wherein the air passageway (52) is further configured to guide air through an inside and / or along an outer surface of the IR modules (62) for cooling and to discharge air having passed and cooled the IR modules (62) from the internal space (34) of the support member (32) through one or more air discharge ducts (48), which are respectively attached to one or more outer wall portion of the plurality of outer wall portions and in fluid connection with the internal space (34) of the support member (32) so as to receive the air discharged from the internal space (34) of the support member (32).

11. Dryer section assembly (1) of any one of claims 1 to 4, wherein the IR device (60) comprises an IR device housing (64), which extends in an elongated manner in said cylinder inter-space (16) along a longitudinal direction of the IR device housing (64) and which accommodates the IR modules (62) of the IR device (60) in an internal space (66) thereof, wherein the support member (32) comprises a plurality of support links (68) which are connected with one end thereof to the support member housing (40) and which are connected with the other end thereof to the IR device housing (64) so as to hingedly connect the support member housing (40) and the IR device housing (64) with each other, wherein air for convective cooling the IR modules (62) is supplied to the internal space (66) of the IR device housing (64) by at least one of an internal channel (70) which is provided in at least one support link (68) and is in fluid connection with both the support member (32) and the internal space (66) of the IR device housing (64) so as to allow air to flow from the support member (32) to the IR device housing (64), and the one or more cooling air supply lines (74) which are comprised in the dryer section assembly (1) and are in fluid connection with the IR modules (62) and provided separate from the support member (32), wherein, optionally, by means of the hinge connection between the support member housing (40) and the IR device housing (64), the IR device housing (64) is pivotable between a first pivotal position, in which the IR device housing (64) is positioned away from the paper web (W) moving through said cylinder inter-space (16) and is positioned closer to the support member housing (40), and a second pivotal position, in which the IR device housing (64) is positioned closer to the paper web (W) moving through said cylinder inter-space (16) and is positioned away from the support member housing (40), wherein, further optionally, the IR device housing (64) is pivotable to any position between the first pivotal position and second pivotal position.

12. Dryer section assembly (1) of any one of the preceding claims, wherein the dryer section assembly (1) further comprises a fire detection means (80) which is arranged on or inside of at least one of the support device (30) and IR device (60) and which is configured to detect and provide a notification of a fire, and wherein the dryer section assembly (1) further comprises a fire-fighting system (100) which is in fluid connection with the support device (30) and the IR device (60) and is configured to introduce fire-extinguishing and / or fire-retarding gas into the support device (30) and the IR device (60) upon notification of a fire from the fire detection means (80).

13. Dryer section assembly (1) of any one of the preceding claims, wherein the dryer section assembly (1) is configured as a double-felted dryer section assembly further comprising a first drying felt (15a) and a second drying felt (15b), wherein the plurality of cylinders (10) comprising a plurality of first cylinders (10a) and a plurality of second cylinders (10b), the first cylinders (10a) are configured to be at least partially wrapped by the first drying felt (15a) and the second cylinders (10b) are configured to be at least partially wrapped by the second drying felt (15b), the dryer section assembly (1) is configured for transferring the paper web (W) between the first cylinders (10a) and the second cylinders (10b) at least partially by a free draw (FD) in a free draw section, and the IR device (60) is configured to emit infrared light towards at least the paper web in the free draw section, wherein, optionally: the first cylinders (10a) comprise a first drying cylinder (12a) and the second cylinders (10b) comprise a second drying cylinder (12b), the drying cylinders (12a, 12b) being configured to guide the paper web (W) at least partially on said circumferential contact surface (13) in the paper conveying direction (CD) between the circumferential contact surface (13) and the corresponding one of the first and second drying felts (15a, 15b), and to dry the paper web (W) by application of heat to the paper web (W) via said circumferential contact surface (13), and the first cylinders (10a) a first felt guide cylinder (14a) and the second cylinders (10b) comprise a second felt guide cylinder (14a), the felt guide cylinders (14a) being configured to support and guide the corresponding one of the first and second drying felts (15a, 15b), wherein the first and second drying felts (15a, 15b) are configured to support the paper web (W) and urge the paper web (W) towards the circumferential contact surface (13) of the drying cylinders (12a, 12b), wherein the cylinder inter-space (16) is defined at least between the first drying cylinder (12a), the second drying cylinder (12b), the first felt guide cylinder (14a) and the second felt guide cylinder (14b).

14. Usage of an infrared (IR) device (60) for drying a paper web (W) in a cylinder inter-space (16) between at least two cylinders of the plurality of cylinders (10) of a dryer section assembly, optionally in a dryer section assembly (1) according to any one of the preceding claims, during paper production, the IR device (60) comprising a plurality of IR modules (62), optionally a plurality of electrically-powered IR modules, and being connected to and supported by a support member (32) which is arranged in said cylinder inter-space (16) and extends in an elongated manner in said cylinder inter-space (16), wherein the IR device (60) is cooled by air, which flows in an internal space (34) of the support member (32) and is guided to the IR modules (62) for convective cooling of the IR modules (62), and / or air, which is supplied by one or more cooling air supply lines (74) of the dryer section assembly (1), which are in fluid connection with the IR modules (62) and provided separate from the support member (32).

15. Method of drying a paper web (W) in a dryer section assembly (1) during paper production, the method comprising arranging (S210) a support device (30) and an infrared (IR) device (60) in a cylinder inter-space (16) between at least two adjacent cylinders of a plurality of cylinders (10) of a dryer section assembly, optionally in a dryer section assembly (1) according to any one of the preceding claims, the support device (30) being connected to and supporting the IR device (60), and the IR device (60) having a plurality of IR modules (62), optionally a plurality of electrically-powered IR modules, air-cooling (S220) the IR modules (62) of the IR device (60), drying and / or ventilating (S230) the paper web (W) moving through said cylinder inter-space (16) by emitting infrared light by means of the air-cooled IR modules (62) towards the paper web (W) moving through said cylinder inter-space (16) and / or blowing air from the support device (30) towards the paper web (W) moving through said cylinder inter-space (16), wherein, optionally, the air blown towards the paper web (W) corresponds to or at least partially comprises the air heated during air-cooling the IR modules (62) of the IR device (60).

Images