Method for baking a continuous mat of mineral or plant fibers

Patent metadata

Field	Value
Publication number	US-10279511-B2
Application number	US-201314419077-A
Country	US
Kind code	B2
Filing date	Jul 25, 2013
Priority date	Jul 31, 2012
Publication date	May 7, 2019
Grant date	May 7, 2019

Abstract

A method for baking a continuous mat of mineral or plant fibers successively includes application of an aqueous solution, containing a binder diluted in the solution, onto mineral or plant fibers, shaping of the fibers to form a continuous mat on a conveyor in motion, and heating the mat in movement through an oven by a hot air flow at a temperature higher than the curing temperature of the binder. Furthermore, at least partial drying of the mat is carried out before entry into the oven. The at least partial drying includes irradiation of the mat in movement with radiofrequency electromagnetic waves whose frequency lies between 3 MHz and 300 GHz.

First claim

The invention claimed is:

1. A method for baking a continuous mat of mineral or plant fibers, or of glass or rock type, successively comprising:
application of an aqueous solution, containing a binder diluted in the solution, onto mineral or plant fibers;
shaping of the fibers to form a continuous mat on a conveyor in motion;
heating the mat in movement through an oven by a hot air flow at a temperature higher than a curing temperature of the binder;
at least partial drying of the mat before entry into any oven for heating, the at least partial drying including irradiation of the mat in movement with radiofrequency electromagnetic waves whose frequency lies between 3 MHz and 300 GHz,
wherein during the at least partial drying of the mat before entry into any oven for heating, air at a temperature less than curing temperature of the binder is blown onto the mat in an irradiation zone to remove moisture,
wherein the oven includes a plurality of compartments, and
wherein one or more of the compartments introduces hot air from a bottom of the oven in a direction transverse to a direction of movement of the mat and the hot air is extracted though a top of the oven, and one or more of the compartments introduce hot air from the top of the oven in a direction transverse to the direction of movement of the mat and the hot air is extracted through the bottom of the oven.

2. The method as claimed in claim 1 , wherein the mat is irradiated with a sufficient power so that presence of water in the mat after at least partial drying by irradiation is less than a predetermined value.

3. The method as claimed in claim 1 , wherein an irradiation power is selected such that temperature of the mat during the at least partial drying remains less than the curing temperature of the binder.

4. The method as claimed in claim 1 , wherein an irradiation power is selected such that left/right difference in percentage of water by mass in the mat is reduced to less than 30% after irradiation.

5. The method as claimed in claim 1 , wherein the irradiation is carried out over an entire width of the mat in movement.

6. The method as claimed in claim 1 , wherein temperature of the hot air blown into at least one compartment of the oven is at least 100° C. higher than the curing temperature of the binder.

7. The method as claimed in claim 1 , wherein the air is blown into the oven through the mat.

8. The method as claimed in claim 1 , wherein density of the mat lies between 5 and 250 kg/m 3 .

9. A method for manufacturing a continuous mat of mineral or plant fibers comprising fibering with fibering equipment comprising a centrifuge or a set of centrifuges, or a rotor or a set of rotors, followed by a baking method as claimed in claim 1 .

10. A method for baking a continuous mat of mineral or plant fibers, or of glass or rock type, successively comprising:
application of an aqueous solution, containing a binder diluted in the solution, onto mineral or plant fibers, the application being made by spraying or atomization in fractions of binder solution;
shaping of the fibers to form a continuous mat on a conveyor in motion;
heating the mat in movement through an oven by a hot air flow at a temperature higher than a curing temperature of the binder;
at least partial drying of the mat before entry into the oven, the at least partial drying including irradiation of the mat in movement with radiofrequency electromagnetic waves whose frequency lies between 3 MHz and 300 GHz,
wherein during the at least partial drying of the mat before entry into any oven for heating, air at a temperature less than curing temperature of the binder is blown onto the mat in an irradiation zone to remove moisture,
wherein the oven includes a plurality of compartments, and
wherein one or more of the compartments introduces hot air from a bottom of the oven in a direction transverse to a direction of movement of the mat and the hot air is extracted though a top of the oven, and one or more of the compartments introduce hot air from the top of the oven in a direction transverse to the direction of movement of the mat and the hot air is extracted through the bottom of the oven.

Assignees

• Saint Gobain Isover

Inventors

• Nguyen Christine
• Vianey Francois
• Letourmy Arnaud

Classifications

• F26B17/026

  the material being moved in-between belts which may be perforated · CPC title

• F26B13/101

  Supporting materials without tension, e.g. on or between foraminous belts · CPC title

• F26B3/347

  Electromagnetic heating, e.g. induction heating or heating using microwave energy · CPC title

• D04H1/64

  the bonding agent being applied in wet state, e.g. chemical agents in dispersions or solutions · CPC title

• D04H1/587

  characterised by the bonding agents used · CPC title