EP4793416A2 - System for curing a mineral wool web - Google Patents

System for curing a mineral wool web

Info

Publication number
EP4793416A2
EP4793416A2 EP26171554.4A EP26171554A EP4793416A2 EP 4793416 A2 EP4793416 A2 EP 4793416A2 EP 26171554 A EP26171554 A EP 26171554A EP 4793416 A2 EP4793416 A2 EP 4793416A2
Authority
EP
European Patent Office
Prior art keywords
gas
oven chamber
heating
upper belt
mineral wool
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
EP26171554.4A
Other languages
German (de)
French (fr)
Inventor
Simon Arnhild LARSEN
Povl Nissen
Kenn Christensen
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Rockwool AS
Original Assignee
Rockwool AS
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Rockwool AS filed Critical Rockwool AS
Priority to EP26171554.4A priority Critical patent/EP4793416A2/en
Publication of EP4793416A2 publication Critical patent/EP4793416A2/en
Pending legal-status Critical Current

Links

Classifications

    • D—TEXTILES; PAPER
    • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
    • D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
    • D04H1/00—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres
    • D04H1/40—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties
    • D04H1/42—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties characterised by the use of certain kinds of fibres insofar as this use has no preponderant influence on the consolidation of the fleece
    • D04H1/4209—Inorganic fibres
    • D—TEXTILES; PAPER
    • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
    • D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
    • D04H1/00—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres
    • D04H1/40—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties
    • D04H1/42—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties characterised by the use of certain kinds of fibres insofar as this use has no preponderant influence on the consolidation of the fleece
    • D04H1/4209—Inorganic fibres
    • D04H1/4218—Glass fibres
    • D—TEXTILES; PAPER
    • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
    • D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
    • D04H1/00—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres
    • D04H1/40—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties
    • D04H1/42—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties characterised by the use of certain kinds of fibres insofar as this use has no preponderant influence on the consolidation of the fleece
    • D04H1/4209—Inorganic fibres
    • D04H1/4218—Glass fibres
    • D04H1/4226—Glass fibres characterised by the apparatus for manufacturing the glass fleece
    • D—TEXTILES; PAPER
    • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
    • D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
    • D04H1/00—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres
    • D04H1/40—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties
    • D04H1/58—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties by applying, incorporating or activating chemical or thermoplastic bonding agents, e.g. adhesives
    • D04H1/64—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties by applying, incorporating or activating chemical or thermoplastic bonding agents, e.g. adhesives the bonding agent being applied in wet state, e.g. chemical agents in dispersions or solutions
    • D04H1/645—Impregnation followed by a solidification process
    • D—TEXTILES; PAPER
    • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
    • D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
    • D04H3/00—Non-woven fabrics formed wholly or mainly of yarns or like filamentary material of substantial length
    • D04H3/002—Inorganic yarns or filaments
    • D04H3/004—Glass yarns or filaments
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F26—DRYING
    • F26B—DRYING SOLID MATERIALS OR OBJECTS BY REMOVING LIQUID THEREFROM
    • F26B17/00—Machines or apparatus for drying materials in loose, plastic, or fluidised form, e.g. granules, staple fibres, with progressive movement
    • F26B17/02—Machines or apparatus for drying materials in loose, plastic, or fluidised form, e.g. granules, staple fibres, with progressive movement with movement performed by belts carrying the materials; with movement performed by belts propelling the materials over stationary surfaces
    • F26B17/026—Machines or apparatus for drying materials in loose, plastic, or fluidised form, e.g. granules, staple fibres, with progressive movement with movement performed by belts carrying the materials; with movement performed by belts propelling the materials over stationary surfaces the material being moved in-between belts which may be perforated
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27B—FURNACES, KILNS, OVENS OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
    • F27B9/00—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity
    • F27B9/06—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity heated without contact between combustion gases and charge; electrically heated
    • F27B9/10—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity heated without contact between combustion gases and charge; electrically heated heated by hot air or gas
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27B—FURNACES, KILNS, OVENS OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
    • F27B9/00—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity
    • F27B9/14—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity characterised by the path of the charge during treatment; characterised by the means by which the charge is moved during treatment
    • F27B9/20—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity characterised by the path of the charge during treatment; characterised by the means by which the charge is moved during treatment the charge moving in a substantially straight path
    • F27B9/24—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity characterised by the path of the charge during treatment; characterised by the means by which the charge is moved during treatment the charge moving in a substantially straight path being carried by a conveyor
    • F27B9/243—Endless-strand conveyor
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27B—FURNACES, KILNS, OVENS OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
    • F27B9/00—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity
    • F27B9/30—Details, accessories or equipment specially adapted for furnaces of these types
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27B—FURNACES, KILNS, OVENS OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
    • F27B9/00—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity
    • F27B9/30—Details, accessories or equipment specially adapted for furnaces of these types
    • F27B9/3005—Details, accessories or equipment specially adapted for furnaces of these types arrangements for circulating gases

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Textile Engineering (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Inorganic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Dispersion Chemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Manufacturing & Machinery (AREA)
  • Tunnel Furnaces (AREA)

Abstract

One embodiment of the invention is a system for curing a mineral wool web comprising a curing oven and at least two heating gas circulation systems wherein the curing oven comprises, an upper belt box, an oven chamber, at least one upper conveyor for transporting the mineral wool web through the oven chamber where at least a part of the upper conveyor is positioned in such a way that it is capable of passing through the oven chamber and the upper belt box and at least one lower conveyor for transporting the mineral wool though the oven chamber. Another embodiment of the invention is a method for curing a mineral wool web is such as system. One advantage of the invention is heating of the mineral wool web can be carried out from both sides of the web at the same time. Another advantage is that gas circulating in the upper belt box does not come into direct contact with the mineral wool web.

Description

    Field of the invention
  • The invention relates to a system for curing a mineral wool web comprising a curing oven.
    • Background
  • Mineral wool is made for many purposes, and mainly for use as insulation material. Due to the characteristics of the mineral wool as an insulation material, it is difficult to cure the wool, once it has been produced and a binder composition introduced into it. Using hot gas and specifically hot air to heat a mineral wool web is well known from for instance US 4263007 A .
    • Summary of the invention
  • When mineral wool is cured by a flow of hot gas, the side of the mineral wool from where the gas is pushed into the wool will be cured first because the binder composition here will achieve its curing temperature first. Depending on the thickness of the mineral wool web the opposite side of the web from where the hot gas is pushed into the wool will reach the curing temperature much later. The uncured mineral wool can be deformed or break apart by the force of the hot gas being push into or through it. Once the binder composition within the mineral wool begins to cure, the mineral wool web becomes stronger and the force of the hot gas can be increased, increasing the rate of heating of the mineral wool web. Therefore, it is important to cure the surfaces of the mineral wool web. This can be achieved by heating the web from both surfaces using different means for heating it.
  • Handling and curing a mineral wool web produces loose fibres and other debris which may accumulate as dirt in the curing oven. The gasses flowing out of the curing oven and especially from any space where the mineral wool web is being passed through may therefore contain these loose fibres, debris and off gasses from the curing process.
  • Therefore, the present invention provides an additional source of heating gas in an upper belt box. The additional source of heat heats the conveying parts of an upper conveyor when they pass through the upper belt box. When the heated conveying parts come into contact with the upper surface of the wool, the heat will dissipate into the wool web and cure the binder composition locally. In this way the issues of the wool breaking apart of becoming deformed are avoided. Once an upper layer of cured wool has been obtained in the wool web the flow of hot gas can be increased. By having more than one heat source in the curing oven a more uniform curing is obtained, and a faster overall curing can be achieved because the flow of hot gas can be increased at a quicker rate. Consequently, the whole of the mineral wool web can be cured quicker and in a more uniform manner.
  • The present invention also provides that this additional source of heating gas in the upper belt box is a separate source of gas such that this gas is not mixed with gasses from an oven chamber before entering the upper belt box. In this manner the amount of loose fibres and debris within the upper belt box is reduced or possibly removed. The reduction of the amount of loose fibres, debris and off gasses in the upper belt box reduces the amount of cleaning needed for this part of the curing oven.
    • Detailed description
  • One embodiment of the present invention is a system for curing a mineral wool web, the system comprising a curing oven and at least two heating gas circulation systems wherein the curing oven comprises;
    • an upper belt box;
    • an oven chamber;
    • at least one upper conveyor for transporting the mineral wool through the oven chamber where at least a part of the upper conveyor is positioned in such a way that it is capable of passing through the oven chamber and the upper belt box and;
    • at least one lower conveyor for transporting the mineral wool though the oven chamber
    wherein one of the at least one heating gas circulation systems is an upper belt box heating gas circulation system for circulating heating gas through the upper belt box and another of the at least two gas circulation systems is an oven chamber heating gas circulation system for circulating heating gas through the oven chamber.
  • Preferably the curing oven comprises two separate chambers, the upper belt box and the oven chamber. Heating gas is circulated through both of these chambers separately to cure a mineral wool web within the oven chamber by heating the oven chamber to one temperature and heating the upper belt box to a higher temperature.
  • Preferably, this system allows heating of both sides (or an upper and lower surface) of the mineral wool web when the upper belt is heated by the upper belt box and the heating gas in the oven chamber enters from the bottom side of the mineral wool web thereby heating the side of the mineral wool web where it enters the wool. Accordingly, the upper belt heats a surface designated as an upper surface of the mineral wool and the oven chamber heats a surface designated as a lower surface of the mineral wool.
  • Preferably the heating gas circulating through the upper belt box can be considered to be circulating in a clean part of the system as it does not come into direct contact with the mineral wool web, while the heating gas circulating through the oven chamber is mixed with vapors coming from the binder composition, vapors emanating from the curing of the binder composition and loose fibres as it passes through and/or around the mineral wool web.
  • Preferably the heating gas is circulated in the two systems without any deliberate addition of gas or air. As the curing oven is kept at a pressure which is lower than the atmospheric pressure of the surrounding environment, air from the surroundings may enter into both the oven chamber and the upper belt box. The lower pressure in the oven chamber and the upper belt box ensures that gasses from the curing oven are not expelled into the surrounding environment.
  • Preferably, the at least one upper conveyor is configured to be heatable. Preferably heatable in the upper belt box. Preferably the at least one upper conveyor is provided with at least one heatable part which is heated in the upper belt box.
  • Preferably the at least one heatable part is able to absorb heat. Preferably, the at least one heatable part is formed from perforated metal, such as steel slats. If the heatable parts are formed from perforated metal, they have the advantage of being able to absorb a significant amount of heat, withstanding the temperature in both the oven chamber and the upper belt box and allowing gasses in the oven chamber to travel through them.
  • Preferably, heating the mineral wool web from different sides using different means ensures that the outer parts of the mineral wool web are cured close to where the mineral wool web enters the oven chamber. Once curing has taken place in the outer parts of the mineral wool web the pressure from the gas heating the mineral wool web may be increased with less risk that the mineral wool web will deform or break apart.
  • Preferably, heating the mineral wool web from different sides at the beginning of the curing process means that the binder composition at the surfaces of the mineral wool does not adhere to the conveyors because the heating is carried out at a time when the binder composition comprises a relatively high amount of water. Once the heat in the oven chamber has evaporated water from the binder composition the still uncured, but now dewatered binder composition can become sticky and adhere the wool to the conveyors. This problem is avoided when the outside surfaces of the mineral wool web are cured at the front of the curing oven.
  • Preferably, there is provided more than two, a plurality of or several sources of heat or heating gas circulation systems to be used in combination to cure the mineral wool. The different parts of the curing oven are able to transfer the heat towards the mineral wool in different manners. In the oven chamber, the heating can be provided by a number of inlets for distributing a flow of hot gas across one surface of the mineral wool web, such as the bottom surface. Accordingly, the oven chamber gas circulation system can be provided with a plurality of inlets for distributing a flow of hot gas across the surface of the mineral wool web. The binder composition within the mineral wool will be heated directly by this flow of gas and by any heat transferred into the binder composition through the mineral wool fibres absorbing heat from their surroundings. While the hot gas moves through the mineral wool web, this type of heat will be absorbed quickly because of the size of the heat exchanging area which exists between the hot gas and the mineral wool web. Additionally, other heating means such as resistance heaters or gas burner could be placed within the oven chamber.
  • Preferably, additional heat can be introduced into the oven chamber through the conveyors and in particularly through the upper conveyor. This is achieved by having the upper conveyor pass through the upper belt box which can have heating gas circulating through it, which is separate to the heating gas in the oven chamber.
  • Preferably, ,maintaining a temperature in the upper belt box which is higher than the temperature in the oven chamber which allows heating of a part of the at least one upper conveyor, for example the at least one heatable part, which, in use, can move into the upper belt box from the oven chamber before it moves back into the oven chamber. Having the upper belt box as a separate chamber from the oven chamber mitigates that the gasses within the upper belt box are transferred into the oven chamber and also allows the temperature within the upper belt box to be higher than what can be allowed within the oven chamber before the mineral wool is damaged.
  • Preferably, the upper conveyor is positioned such that it is capable of exiting the upper belt box and entering an outside or an outside area of the curing oven before it enters the oven chamber. Accordingly, the upper belt box does not come into direct contact with the mineral wool web as it is passed through the curing oven. This mitigates the entrance of mineral wool fibres into the upper belt box, as they would have to be picked up by the upper conveyor to enter the upper belt box. Therefore, this way of constructing the upper belt box and positioning the upper conveyor belt keeps the upper belt box cleaner and requires less cleaning maintenance of the upper belt box.
  • Preferably, the upper belt box comprises at least one heating gas inlet and at least one heating gas outlet.
  • Preferably, the upper belt box heating gas circulation system comprises a gas heating source, for example, a belt box gas heating source.
  • Preferably the oven chamber circulation system comprises a gas heating source, for example, an oven chamber gas heating source.
  • Preferably, the gas heating source, for example, the belt box gas heating source and/or the oven chamber gas heating source, comprises electrical heating.
  • Preferably the gas heating source, for example, the belt box gas heating source and/or the oven chamber gas heating source comprises resistive heating.
  • The heat provided in the oven chamber and the upper belt box can be provided by different sources of heat through the at least two heating gas circulation systems. The preferred option for these sources is electrical heating and specifically resistive heating because such heat sources are able to provide heating gas at the temperatures able to perform the curing of the mineral wool web within the curing oven while minimizing the amount of additional gas added to the heating gas streams being circulated in the gas circulation systems. Electrical heating such resistive heating also minimizes the amount of pollutants introduced in the heating gas stream as compared to, for example, heating through combustion of gas.
  • Preferably, it further comprises an abatement system in fluid communication with one or more or both of the at least two heating gas circulations systems. Preferably, the upper belt box heating gas circulation system and/or the oven chamber heating gas circulation system.
  • Preferably, both excess heating gas and vapors from the heating and curing of any curing composition (off gases) should be removed from the system to prevent them from accumulating in the system. Therefore, off gases can be removed from both the upper belt box circulation system and the oven chamber circulation system. Pollutants present in these off gases should be removed or transformed before the gases are released into the environment. This removal or transformation is carried out in an abatement system.
  • Preferably, the abatement system comprises one or more steps such as catalytic treatment steps and adsorption steps to transform or remove the compounds within the off gases.
  • Preferably, such steps function at different optimal temperatures. Therefore, preferably, the abatement system comprises one or more temperature changing steps including heat exchange to use the energy of different gas streams within the system more efficiently and heating steps to control the temperature of the exhaust or off gases before it enters specific treatment steps.
  • One temperature changing step which may be applied in the abatement system is, preferably, a regenerative thermal oxidation step or RTO step.
  • The catalytic treatment steps in the gas cleaning system are ones that are able to transform organic compounds within the exhaust into carbon dioxide and water and to transform ammonia (NH3) and nitrogen oxides (NOX) or nitrous oxide (N2O) into nitrogen (N2). Therefore, preferably, the catalytic treatment steps comprise oxidation catalysts, selective catalytic reduction (SCR) catalysts and/or combinations thereof.
  • Preferably, the gas cleaning system can also comprise other treatment steps such as filters and adsorbers which are able to remove particles such as loose fibres in the exhaust and adsorb different chemical compounds according to the kind of adsorber used.
  • According to an embodiment of the present invention there is provided a method for curing a mineral wool web in a system according to the present invention.
  • According to an embodiment of the present invention there is provided a method for curing a mineral wool web in a system comprising a curing oven and at least two heating gas circulation systems wherein the curing oven comprises;
    • an upper belt box;
    • an oven chamber;
    • at least one upper conveyor for transporting the mineral wool web through the oven chamber where at least a part of the upper conveyor is positioned in such a way that it is capable of passing through the oven chamber and the upper belt box and;
    • at least one lower conveyor for transporting the mineral wool though the oven chamber;
    wherein one of the at least two heating gas circulation systems is an upper belt box heating gas circulation system for circulating and/or heating gas through the upper belt box and another of the at two heating gas circulation systems is an oven chamber heating gas circulation system for circulating and/or heating gas through the oven chamber, wherein the method comprises the steps of:
    • passing the mineral wool web through the oven chamber;
    • passing heating gas through the oven chamber and passing it through the mineral wool web and circulating this heating gas through the oven chamber heating gas circulation system;
    • passing heating gas through the upper belt box and circulating this heating gas through the upper belt box heating gas circulation system.
  • Preferably, the heating gas passing through the upper belt box heating gas circulation system is heated outside the curing oven.
  • Preferably, the heating gas passing through the oven chamber heating gas circulation system is heated outside the curing oven.
  • An advantage of heating the mineral wool web through two separate gas circulation system is that the mineral wool web may be heated from different sides at the same time. When this is done at the beginning of the curing process the binder composition at the surfaces of the mineral wool does not adhere to the conveyors because the heating is carried out at a time when the binder composition comprises a relatively high amount of water. Once the heat in the oven chamber has evaporated water from the binder composition the still uncured, but now dewatered binder composition can become sticky and adhere the wool to the conveyors. This problem is avoided when the outside surfaces of the mineral wool web are cured at the beginning of the curing process.
  • Preferably, the heating gas in the upper belt box heating gas circulation system is heated to a higher temperature than the heating gas in the oven chamber heating gas circulation system.
  • As the heating gas in the upper belt box does not come into direct contact with the binder composition of the mineral wool web, the temperature of this gas can be higher than the gas within the oven chamber without causing any damage to the mineral wool web or decomposing the binder or the binder composition.
  • The temperature during the curing of the binder composition in the mineral wool depends on the type of binder composition which is added to the mineral wool after it has been spun. The general temperature range within the oven chamber is between about 150 to about 330°C. Phenol, formaldehyde binders which can be optionally modified by urea (PUF binders) are cured in the middle part of this interval preferably within about 200 to about 230 °C. Protein based binders cure at the lower end of the range while sugar-based binders are cured at the higher end of the range.
  • For energy to be transferred from the upper belt box through the parts of the upper conveyor which are passing through the upper belt box, the temperature here, preferably, has to be higher than in the oven chamber. Therefore, the temperature in the upper belt box is generally within the range of about 220 to about 350 °C.
  • Within this specification aspects and embodiments have been described in a way which enables a clear and concise specification to be written, but it is intended and will be appreciated that aspects and embodiments may be variously combined or separated without parting from the invention. For example, it will be appreciated that all preferred features described herein are applicable to all aspects of the invention described herein and vice versa.
  • Within this specification, the term "about" means plus or minus 20%, more preferably plus or minus 10%, even more preferably plus or minus 5%, most preferably plus or minus 2%. It will also be appreciated that the disclosure extends to passages herein which refer to the term "about" but with said term removed.
    • Brief description of the drawing
  • Figure 1 shows a schematic view of one embodiment of the invention.
    • Detailed description of the drawing
  • A system (100) according to one embodiment of the invention is shown in Figure 1. This system comprises a curing oven (1) and two heating gas circulation systems, one upper belt box heating gas circulation system (20) and an oven chamber heating gas circulation system (30). The curing oven (1) comprises an upper belt box (2) and an oven chamber (3). In use a mineral wool web (6) is passed through the oven chamber (3). This mineral wool web (6) is transported through the oven chamber (3) by two conveyor belts, an upper conveyor (4) and a lower conveyor (5). The upper conveyor (4) is positioned such that it is capable of passing through the oven chamber (3) and the upper belt box (2). Heating gas (not shown) is passed through the mineral wool web (6) within the oven chamber (3) to cure any binder composition present in the mineral wool web (6) as it enters the oven chamber (3). This heating gas (not shown) is provided through the oven chamber heating gas circulation system (30) where gas (not shown) from the oven chamber exits through one or more oven chamber outlets (32), is circulated to a first electrical heater (10a) and reenters the oven chamber (3) through at least one oven chamber inlet (31). Additional heat is provided in the upper belt box (2) through the upper belt box heating gas circulation system (20). Gas exits the upper belt box (2) through at least one upper belt box outlet (22), is circulated to a second electrical heater (10b) and reenters the upper belt box through at least one upper belt box inlet (21). This heats the part of the upper conveyor (4) passing through the upper belt box (2) and this heat is passed onto the mineral wool web (6) when the upper conveyor (4) comes into contact with the mineral wool web (6). Because the pressure within the curing oven (1) is kept below the pressure of the surrounding atmosphere and below atmospheric pressure, gases or air from the surrounding environment enter the curing oven (1) producing an excess of gases within both gas circulation systems.
  • Additionally, gases are produced through the curing process mainly from evaporation of water. These excess gases are removed through an abatement system (50) which is connected to both the upper belt box gas circulation system (20) and the oven chamber gas circulation system (30). This abatement system (50) removes or transforms pollutants in excess or off gases before they are let out through an outlet such as a chimney (60).

Claims (13)

  1. A system for curing a mineral wool web, the system comprising a curing oven and at least two heating gas circulation systems wherein the curing oven comprises;
    an upper belt box;
    an oven chamber;
    at least one upper conveyor for transporting the mineral wool web through the oven chamber where at least a part of the upper conveyor is positioned in such a way that it is capable of passing through the oven chamber and the upper belt box and;
    at least one lower conveyor for transporting the mineral wool though the oven chamber
    wherein one gas circulation system is an upper belt box gas circulation system for circulating heating gas through the upper belt box and another gas circulation system is an oven chamber gas circulation system for circulating and heating gas through the oven chamber.
  2. The system according to claim 1, the upper conveyor is positioned such that it is capable of exiting the upper belt box and entering the outside of the curing oven before it enters the oven chamber.
  3. The system according to any one of the preceding claims, wherein the upper belt box comprises at least one heating gas inlet and at least one heating gas outlet.
  4. The system according to any one of the preceding claims, wherein the upper belt box circulation system comprises a gas heating source.
  5. The system according to any one of the preceding claims, wherein the oven chamber circulation system comprises a gas heating source.
  6. The system according to any one of claims 4 or 5 wherein the gas heating source comprises electrical heating.
  7. The system according to any one of claims 4 to 6 wherein the gas heating source comprises resistive heating.
  8. The system according to any one of the preceding claims wherein the system further comprises an abatement system in fluid communication with both gas circulation systems.
  9. The system according to claim 8 wherein the abatement system comprises a regenerative thermal oxidation (RTO) and a selective catalytic reduction (SCR).
  10. A method for curing a mineral wool web in a system comprising a curing oven and at least two heating gas circulation systems wherein the curing oven comprises;
    an upper belt box;
    an oven chamber;
    at least one upper conveyor for transporting the mineral wool web through the oven chamber where at least a part of the upper conveyor is positioned in such a way that it is capable of passing through the oven chamber and the upper belt box and;
    at least one lower conveyor for transporting the mineral wool though the oven chamber
    wherein one gas circulation system is an upper belt box gas circulation system for circulating heating gas through the upper belt box and another gas circulation system is an oven chamber gas circulation system for circulating and heating gas through the oven chamber, wherein the method comprises the steps of:
    passing the mineral wool web through the oven chamber,
    passing heating gas through the oven chamber and passing it through the mineral wool web and circulating this heating gas through the oven chamber gas circulation system,
    passing heating gas through the upper belt box and circulating this heating gas through the upper belt box gas circulation system.
  11. The method according to claim 10 wherein the heating gas passing through the upper belt box gas circulation system is heated outside the curing oven.
  12. The method according to any one of claims 10 to 11 wherein the heating gas passing through the oven chamber gas circulation system is heated outside the curing oven.
  13. The method according to any one of claims 10 to 12 wherein the heating gas in the upper belt box gas circulation system is heated to a higher temperature than the heating gas in the oven chamber gas circulation system.
EP26171554.4A 2026-04-09 2026-04-09 System for curing a mineral wool web Pending EP4793416A2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
EP26171554.4A EP4793416A2 (en) 2026-04-09 2026-04-09 System for curing a mineral wool web

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP26171554.4A EP4793416A2 (en) 2026-04-09 2026-04-09 System for curing a mineral wool web

Publications (1)

Publication Number Publication Date
EP4793416A2 true EP4793416A2 (en) 2026-08-19

Family

ID=99358987

Family Applications (1)

Application Number Title Priority Date Filing Date
EP26171554.4A Pending EP4793416A2 (en) 2026-04-09 2026-04-09 System for curing a mineral wool web

Country Status (1)

Country Link
EP (1) EP4793416A2 (en)