Enthalpy exchanger element, enthalpy exchanger comprising such elements and method for their production

1. A method for manufacturing one or more enthalpy exchanger elements (E, E′, PR, PL), the method comprising:

a) providing an air-permeable sheet element ( 1 );

b) laminating at least one side ( 1 a , 1 b ) of the sheet element ( 1 ) with a polymer film ( 3 , 4 ) having water vapor transmission characteristics; and

c) forming the laminated sheet element ( 1 ) into a desired shape exhibiting a three-dimensional corrugation pattern ( 5 , 5 , . . . ) said corrugation pattern including one or more parallel flow regions or counter flow regions, a first cross flow region upstream of the one or more parallel flow region or counterflow region and one or more second cross flow region downstream of the one or more parallel flow region or counterflow region, wherein said first or second cross-flow region comprises a plurality of air guiding walls ( 15 , 16 );

thereby producing one or more enthalpy exchanger elements (E, E′, PR, PL) upon completing steps a-c.

2. The method according to claim 1 , wherein the sheet material of the sheet element ( 1 ) comprises a polymer.

3. The method according to claim 1 , wherein the sheet element ( 1 ) is a fabric.

4. The method according to claim 3 , wherein a fraction of the fibers ( 6 ) of the fabric are multi-component.

5. The method according to claim 1 , wherein the laminating step b) further comprises at least one of bonding, welding or gluing, of the polymer film ( 3 , 4 ) to the sheet element ( 1 ).

6. The method according to claim 1 , wherein the at least one polymer film ( 3 , 4 ) on the at least one side ( 1 a , 1 b ) of the sheet element ( 1 ) is an air-impermeable polymer film.

7. The method according to claim 1 , wherein the polymer film ( 3 , 4 ) is a multilayer film comprising a sequence of polymer layers of different polymer types.

8. The method according to claim 7 , wherein the polymer type of each polymer layer is selected from the group consisting of polyether ester, polyether amide and polyether urethane.

9. The method according to claim 7 , wherein the total thickness of the thin polymer multilayer film is between 5 μm and 200 μm.

10. The method according to claim 7 , wherein the thickness of each individual polymer layer within the polymer multilayer film is between 1 μm and 20 μm.

11. The method according to claim 1 , wherein the forming step c) is one of a thermoforming step, a vacuum forming step, a pleating step, or combinations thereof.

12. The method according to claim 11 , wherein said laminated sheet element is formed in step c. by a first mold part having a first corrugation formation defining a predetermined corrugation pattern of the enthalpy exchanger element (E, E′) to be manufactured.

13. The method according to claim 12 , wherein a second mold part having second corrugation formations complementary to the first corrugation formations co-defining the predetermined corrugation pattern of the enthalpy exchanger element (E, E′) to be manufactured, is provided for and used in the thermoforming step c).

14. The method according to claim 10 , wherein nozzles connected to a pressurized air source provided for and used in the thermoforming step c).

15. The method according to claim 14 , wherein the nozzles are provided in the vicinity of the first mold part and/or the second mold part.

16. The method of claim 1 further comprising:

d) repeating steps a), b) and c) to produce a plurality of laminated and formed sheet elements exhibiting a three-dimensional corrugation pattern;

e) stacking the plurality of laminated and formed sheet elements; and

f) fixing the stacked laminated and formed sheet elements to each other.

17. An enthalpy exchanger comprising:

at least three sheet or plate enthalpy exchanger elements (E; E′, PR, PL), produced using the method as defined in claim 1 ;

wherein each enthalpy exchanger element includes:

an air-permeable sheet element ( 1 ); and

a predetermined three-dimensional corrugation pattern ( 5 , 5 , . . . );

wherein a first polymer film ( 3 ) is laminated to a first side ( 1 a ) of the sheet element ( 1 ) and/or a second polymer film ( 4 ) is laminated to a second side ( 1 b ) of the sheet element ( 1 ), the one or both polymer films ( 3 , 4 ) having characteristics for selective water vapor transmission; and

wherein each enthalpy exchanger element further includes a parallel flow region or counter flow region, a first cross flow region upstream of the parallel flow region or counterflow region and a second cross flow region downstream of the parallel flow region or counterflow region; and

wherein the enthalpy exchanger elements are stacked such that right handed enthalpy exchanger elements are alternatingly stacked with left handed enthalpy heat exchanger elements.

18. The enthalpy exchanger element (E, PR, PL) according to claim 17 , wherein the first polymer film ( 3 ) and the second polymer film ( 4 ) are identical to each other.

19. The enthalpy exchanger element (E′, PR, PL) according to claim 17 , wherein the first polymer film ( 3 ) and the second polymer film ( 4 ) are different from each other.

20. The method according to claim 3 , wherein the sheet element ( 1 ) is a nonwoven fabric.

21. The method according to claim 9 , wherein the total thickness of the polymer multilayer film is between 10 μm and 150 μm.

22. The method according to claim 4 , wherein at least 50% by weight of the fibers ( 6 ) of the fabric are bi-component fibers.

23. The method according to claim 10 , wherein the thickness of each individual polymer layer within the thin polymer multilayer film is between 4 μm and 20 μm.

24. The method according to claim 23 , wherein the thickness of each individual polymer layer within the thin polymer multilayer film is between 4 μm and 15 μm.