Enthalpy exchanger element, enthalpy exchanger comprising such elements and method for their production
The present invention provides enthalpy exchanger elements (E, E′) and enthalpy exchangers comprising such elements. Furthermore, the invention discloses a method for producing such enthalpy exchanger elements and enthalpy exchangers, comprising the steps of 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 thin polymer film ( 3, 4 ) with water vapor transmission characteristics; and c) forming the laminated sheet element ( 1 ) into a desired shape exhibiting a three-dimensional corrugation pattern ( 5, 5 , . . . ).
1. A method of manufacturing an enthalpy exchanger, 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 ) with water vapor transmission characteristics; and
c) forming the laminated sheet element ( 1 ) into a desired shape exhibiting a three-dimensional corrugation pattern ( 5 , 5 , . . . ); and
d) repeating steps a-c to produce at least three laminated sheet elements, wherein said at least three laminated sheet elements exhibiting the three-dimensional corrugation pattern are stacked onto and fixed to each other with each of their respective corrugation patterns in parallel orientation to form parallel fluid paths.
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, preferably at least 50% by weight, of the fibers ( 6 ) of the fabric are multi-component.
5. The method according to claim 1 , wherein the laminating step b) comprises at least one of bonding, welding and 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 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 a thermoforming step.
12. The method according to claim 11 , wherein at least a first mold part having first corrugation formations 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).
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 according to claim 9 , wherein the total thickness of the polymer multilayer film is between 10 μm and 150 μm.
17. The method according to claim 3 , wherein the fabric is a nonwoven fabric.
18. The method according to claim 4 , wherein said multi-component fibers are bi-component fibers.
19. The method according to claim 10 , wherein the thickness of each individual polymer layer within the polymer multilayer film is between 4 μm and 20 μm.
20. The method according to claim 10 , wherein the thickness of each individual polymer layer within the polymer multilayer film is between 4 μm and 15 μm.
21. The method according to claim 11 , wherein said thermoforming step includes vacuum forming, pleating, or combinations thereof.
22. An enthalpy exchanger, comprising:
at least three air-permeable sheet elements ( 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 elements ( 1 ) and/or a second polymer film ( 4 ) is laminated to a second side ( 1 b ) of the sheet elements ( 1 ), both polymer films ( 3 , 4 ) having water vapor transmission characteristics, wherein at least three laminated sheet elements exhibiting the three-dimensional corrugation pattern are stacked onto and fixed to each other with each of their respective corrugation patterns in parallel orientation to form parallel fluid paths.
23. The enthalpy exchanger according to claim 22 , wherein the first polymer film ( 3 ) and the second polymer film ( 4 ) are identical to each other.
24. The enthalpy exchanger according to claim 22 , wherein the first polymer film ( 3 ) and the second polymer film ( 4 ) are different from each other.
25. The enthalpy exchanger according to claim 22 wherein the laminated sheet elements are fixed to each other by welding, gluing, or combinations thereof.
26. The enthalpy exchanger according to claim 25 wherein said welding is laser welding, ultrasonic welding, or combinations thereof.