WATER EXTRACTION FACILITY

Abstract

A water extraction facility comprising a suction box having a suction opening and a chamber (9) arranged above the suction opening by means of a connector (21) and a perforated sheet metal element (24) creating head loss is mounted in the connector (21).

Claims

1. A water extraction facility comprising a suction box (4) having a suction opening (3) and communicating via a conduit (5) with a separator (6) separating air from water and having a top part, the top part of the separator (6) communicating via pipework (14, 15), on which is mounted a vacuum pump (8), with a chamber (9), disposed above the suction opening (3) and opening out towards the suction opening (3) via a connector (21), characterised in that a perforated sheet metal element (24) creating head loss and having first perforations is mounted in the connector (21), the connector (21) is clamped to a channel (27) in which is mounted a honeycomb bundle (28) with cells, the dimension of the cells of said honeycomb bundle being greater that that of the first perforations of the perforated sheet metal element (24), and the perforated sheet metal element (24) is covered with a metallic web (30) that has a void fraction of between 25 and 50% and that has second perforations of which one dimension is smaller that those of the first perforations of the perforated sheet metal element.

2. The facility according to claim 1, characterised in that the void fraction of the perforated sheet metal element (24) is between 10% and 40%.

3. The facility according to claim 1, characterised in that one dimension of the second perforations of the web is between 0.1 and 1 mm.

4. The facility according to claim 1, characterised in that if one calls Se the inlet section in the chamber, if one calls S1 the connector 21 section (=section of the passage of fluid through the perforated sheet metal element 24 and through the web 30), S2 the channel (27) outlet section and K the head loss coefficient created by the perforated sheet metal element (24) and web (30) assembly, one has
S1.sup.2/K*Se.sup.2)<0.1

5. The facility according to claim 4, characterised in that one has:
S1.sup.2/K*Se.sup.2)<0.3

6. The facility according to claim 4, characterised in that
S2=(0.5 to 1.5)*S1

7. The facility according to claim 6, characterised in that one has:
S2=S1

8. The facility according to claim 4, characterised in that if S3=the section of the passage of fluid through the opening (3) of the suction box (4), one has S2=(3 to 10)*S3.

9. The facility according to claim 1, characterised in that the bundle (28) is supported by another perforated sheet metal element (29) that has a void fraction greater than 40%.

10. The facility according to claim 1, characterised in that the perforated sheet metal element (24) is mounted in a removable drawer (22).

11. The facility according to claim 1, characterised in that the bundle (28) is mounted in a removable drawer.

12. The facility according to claim 2, characterised in that one dimension of the second perforations of the web is between 0.1 and 1 mm.

Description

[0032] In the attached drawings, given purely as examples:

[0033] FIG. 1 illustrates the facility according to the invention,

[0034] FIG. 2 is a perspective view of the diffusion box and

[0035] FIG. 3 is a front view.

[0036] FIG. 4 is a perspective view of another diffusion box.

[0037] The non-woven fabric, saturated with water 1, set in motion by the conveyor web 2, passes above the suction opening 3. The void (−400 to −500 mbar) created in the suction box 4 by the vacuum pump 8 generates an air current through this opening which passes through the non-woven fabric 1+conveyor web 2 assembly, carrying with it some of the water contained in the non-woven fabric 1.

[0038] The air/water mixture which is thus formed is evacuated by pipework 5 to the separator 6.

[0039] The role of the separator 6 is to separate the air and the water by a cyclonic effect: [0040] in the bottom part the water is evacuated by a pump 7 to the filtration circuit or a drain, [0041] in the top part, i.e. above the air and water separation level, the air is evacuated by a vacuum pump 8 through the pipework 14.

[0042] As it passes through the vacuum pump 8, the current of air heats up to a temperature measured by a thermometer 12 and is then carried to a diffusion box 9 by pipework 15, then by a hose 13.

[0043] The diffusion box will diffuse the hot air homogeneously above the suction opening 3.

[0044] The diffusion box shown in FIGS. 2 and 3 comprises a chamber 9 which is, for example, parallelepipedic and has two front faces, one of which is closed and the other of which, with a section Se, receives the hose 13. A parallelepipedic connector 21 of the same length as the chamber leaves the large lower face. The chamber 9 is 200 to 500 mm wide. The width L1 of the connector 21 is 40 to 60 mm. Its named section is S1. Mounted in this connector 21 is a sliding drawer 22 which has a handle 23 and carries a perforated sheet metal element 24 that has a degree of openness of 10 to 40%. The drawer 22 slides in the connector 21 by means of runners 25. The perforated sheet metal element 24 is covered in a fine metallic web 30 which has a void fraction of between 25 and 50 and a diameter of the openings of 0.5 mm. The web 30 is upstream of the sheet metal element 24 in the direction of the passage of air.

[0045] A channel 27 is clamped, by flanges 26, to the connector 21, in which channel is mounted a honeycomb bundle 28 with section S2, S2=L*L2, with L=diffusion zone length=width of the machine and L2=width of the section at the bundle 28 outlet, supported by a perforated sheet metal element 29 that has a void fraction of 40 to 60%. The cells of the honeycomb bundle 28 have a dimension of 4 to 10 mm.

[0046] If one calls Se the inlet section in the chamber. If one calls S1 the connector 21 section (=section of the passage of fluid through the perforated sheet metal element 24 and through the web 30), S2 the channel 27 outlet section, S3 the section of the passage of fluid through the opening (3) of the suction box (4) and K the head loss coefficient created by the perforated sheet metal element 24 and web 30 assembly, one preferably has S1.sup.2/K*Se.sup.2)<0.03 and S2=S1 and S2=6*S3.

[0047] FIG. 4 is a view similar to FIG. 2 of a diffusion box in which the honeycomb bundle 28 is mounted on a removable drawer 31.