Method for preparing an insulating product based on wool, in particular mineral wool

2:

• The method for preparing an insulating product as claimed in claim 1, wherein the wool is a mineral wool.

3:

• The method for preparing an insulating product as claimed in claim 1, wherein the profile of the mean speeds of the wool in the flow in the direction A comprises at least one recirculation zone in which the component of the speed parallel to the direction A is negative, thereby making it possible to generate the flow in the direction B.

4:

• The method for preparing an insulating product as claimed in claim 3, wherein the flow in the direction A comprising a recirculation point comprises a shear zone in which the wool travels in the direction A and a recirculation zone in which the wool travels in the direction B.

5:

• The method for preparing an insulating product as claimed in claim 1, wherein the turbulent flow in the direction A is characterized by a Reynolds number higher than 3000.

6:

• The method for preparing an insulating product as claimed in claim 1, wherein the turbulent flow in the direction A is obtained by entraining the wool using a first air jet.

7:

• The method for preparing an insulating product as claimed in claim 6, wherein the first air jet enters the chamber from an inlet orifice, the flow of the first air jet at the level of the inlet orifice is characterized by a Reynolds number higher than 3000.

8:

• The method for preparing an insulating product as claimed in claim 6, wherein the entrainment in a carrier gas in a direction B that is the opposite to the direction A is obtained by choosing a suitable ratio between the dimensions of the cross section of the inlet orifice and a cross section of the chamber in a plane of the chamber perpendicular to the direction A.

9:

• The method for preparing an insulating product as claimed in claim 1, wherein the chamber comprises a cross section Se and a length L both perpendicular to the direction A which are such that the dimensions of the cross section Se perpendicular to the direction A are sufficient to generate a recirculation point in a plane of the chamber, and the length L is short enough that the recirculation movements are multiplied.

10:

• The method for preparing an insulating product as claimed in claim 8, wherein the aeration step inside the chamber is performed for a duration longer than 10 seconds.

11:

• The method for preparing an insulating product as claimed in claim 1, wherein the entrainment in a carrier gas in a direction B that is the opposite to the direction A is obtained by the use of at least one additional air jet for which the direction in which the air is injected is at least partially the opposite of (in the opposite direction to) or perpendicular to the direction A.

12:

• The method for preparing an insulating product as claimed in claim 11, wherein the additional air jet or jets enter the chamber from inlet orifices, the flow from an additional air jet at the level of these inlet orifices is characterized by a Reynolds number higher than 3000.

13:

• The method for preparing an insulating product as claimed in claim 12, wherein the Reynolds number of the additional air jet is higher than the Reynolds number of the first air jet which carries the wool in the direction A.

14:

• The method for preparing an insulating product as claimed in claim 11, wherein the speed of the additional air jet is higher than the mean speed of the turbulent flow that carries the wool in the direction A.

15:

• The method for preparing an insulating product as claimed in claim 11, wherein the ratio between the speed of the additional air jet and the mean speed of the turbulent flow that carries the wool in the direction A is greater than 1.

16:

• The method for preparing an insulating product as claimed in claim 1, wherein the mean speed of the turbulent flow which carries the wool in the direction A is comprised between 0.5 and 50 m/s.

17:

• The method for preparing an insulating product as claimed in claim 1, wherein the chamber is part of a duct or of a pipe.

19:

• The method for preparing an insulating product as claimed in claim 18, wherein the aeration step is performed after the step of nodulation by grinding and before the bagging step.

20:

• The method for preparing an insulating product as claimed in claim 18, wherein the aeration step is performed after the bagging step.