Installation element for use in the fields of cooling technology, water treatment or mass transfer and method for the manufacture of such an installation element

Abstract

An installation element for use in cooling technology, in water treatment, or in mass transfer and a method for producing such an element. The installation element is sell supporting and is composed of a plurality of plies which are at least partially spatially structured and which are connected to each other. Adjacent plies form flow paths for a liquid and/or a gaseous medium between the adjacent plies. The installation element has at least some of the plies being composed of an at least three-layer coextruded plastic film, a center layer of the three-layer plastic film being a mechanically supporting layer, and the two outer layers are composed of a plastic having application-specific properties or are layers each having at least one additive which is added to the plastic and which gives application specific properties to the outer layers.

Claims

1. An installation element for use in the fields of cooling technology, water treatment or mass transfer, wherein the installation element is self-supporting and is composed of a plurality of individual plies which are, at least in part, structured spatially and are connected to each other, wherein neighboring plies form flow paths between themselves for at least one of a liquid or a gaseous medium, wherein at least some of the individual plies are entirely composed of an at least three-layer coextruded and self-coherent plastic film, a central layer of the three-layer plastic film is a mechanically supporting plastic layer, and the two outer layers of the three-layer plastic film comprise one of a plastic material that comprises application-specific properties or are plastic layers each comprising at least one additive that is added to the plastic material and gives the outer layers application-specific properties.

2. The installation element according to claim 1, wherein the two outer layers each comprise at least one additive and the at least one additive is a substance that is one of antibacterial, promotes microbial growth, is flame-retardant, lowers the surface tension or increases the resistance.

3. The installation element according to claim 1, wherein the plastic material is one of polypropylene (PP), polyvinyl chloride (PVC), polyethylene (PE) or polyvinylidene fluoride (PVDF).

4. The installation element according to claim 1, wherein the central layer of the three-layer coextruded plastic film comprises a thickness which amounts to at least 50 percent of the thickness of the plies comprising the three-layer coextruded plastic film.

5. The installation element according to claim 1, wherein the central layer of the three-layer coextruded plastic film contains a mechanical reinforcement material.

6. The installation element according to claim 1, for use in a cooling tower or air humidifier installation, and wherein the outer layers of the three-layer coextruded plastic film comprise, as an application-specific property, at least one of an antibacterial property or a property that lowers the surface tension.

7. The installation element according to claim 1, for use in a sewage purification plant or fish farm installation, and wherein the outer layers of the three-layer coextruded plastic film, comprise as an application-specific property, a property that promotes a growth of pollutant degrading microorganisms.

8. The installation element according to claim 1, for use in a mass transfer device installation, and wherein the outer layers of the three-layer coextruded plastic film comprise, as an application-specific property, a property that increases the chemical resistance to the media entering into an exchange of materials in the installation element.

9. The installation element according to claim 1, wherein the individual plies of the installation element are connected to each other occasionally.

10. The installation element according to claim 9, wherein the individual plies of the installation element are connected to each other by being one of welded, glued or mechanically clipped.

11. A method for producing an installation element for use in the fields of cooling technology, water treatment or mass transfer, wherein the installation element is self-supporting and comprises: a plurality of individual plies which are, at least in part, structured spatially and are connected to each other, wherein neighboring plies form flow paths between themselves for at least one of a liquid or a gaseous medium, wherein at least some of the individual plies are entirely composed of an at least three-layer coextruded plastic film, a central layer of the three-layer plastic film is a mechanically supporting plastic layer, and the two outer layers of the three-layer plastic film comprise one of a plastic material that comprises application-specific properties or are plastic layers each comprising at least one additive that is added to the plastic material and gives the outer layers application-specific properties, the method comprising the steps: producing at least some of the plies in the form of the at least three-layer plastic film by means of coextrusion, producing a central layer of the three-layer plastic film as a mechanically supporting plastic layer, and producing the two outer layers of the three-layer plastic film either from a plastic material that comprises application-specific properties or generating the two outer layers in the form of plastic layers, each comprising at least one additive that is added to the plastic material and gives the outer layers application-specific properties.

12. The method according to claim 11, comprising a further step of, after extrusion, continuously supplying the three-layer plastic film to a forming tool as a film web, with the film web being continuously formed in said forming tool to form a spatial structure, wherein sections are cut off the film web subsequent to a cooling process fixing the forming, and wherein, in each case, a plurality of sections or section packages are connected to each other to form the installation element or an installation element block.

13. The method according to claim 11, wherein the three-layer plastic film is cooled down and cut into sections after extrusion, wherein the sections are supplied to a forming tool intermittently, with the film web being formed in said forming tool to form a spatial structure by thermoforming, and wherein, in each case, a plurality of sections or section packages are connected to each other to form the installation element or an installation element block subsequent to a cooling process fixing the forming.

14. The method according to claim 12, wherein the installation element blocks are produced in a size that is in excess of the size of the installation elements and wherein subsequently installation elements having the desired dimensions are cut off or out of the installation element blocks.

15. The method according to claim 13, wherein the installation element blocks are produced in a size that is in excess of the size of the installation elements and wherein subsequently installation elements having the desired dimensions are cut off or out of the installation element blocks.

16. An installation element for use in the fields of cooling technology, water treatment or mass transfer, wherein the installation element is self-supporting and is composed of a plurality of individual plies which are, at least in part, structured spatially and are connected to each other, wherein neighboring plies form flow paths between themselves for at least one of a liquid or a gaseous medium, wherein at least some of the individual plies are entirely composed of an at least three-layer coextruded plastic film, the at least three layers each extending across an entire length and width of the film and together having a wavy form, a central layer of the three-layer plastic film is a mechanically supporting plastic layer, and the two outer layers of the three-layer plastic film comprise one of a plastic material that comprises application-specific properties or comprise plastic layers each comprising at least one additive added to the plastic material and giving the outer layers application-specific properties.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Below, an exemplary embodiment of the invention will be illustrated by means of a drawing. In the drawing,

(2) FIG. 1 is a view of one of the front faces of the plies, showing a detail of an installation element consisting of a plurality of plies;

(3) FIG. 2 shows an enlarged detail of a three-layer ply of the installation element shown in FIG. 1; and

(4) FIG. 3 is a schematic diagram of an extruder arrangement for coextrusion of three-layer plastic films for the plies of the installation element.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

(5) FIG. 1 of the drawing is a view of one of the front faces of the plies, showing a detail of an installation element 1 comprising a plurality of plies 10, wherein, in the illustrated instance, only three plies 10 are shown; in practice, the number of plies 10 is considerably higher in a customary installation element 1.

(6) The individual plies 10 each comprise a plastic film having a wavy form wherein, in the illustrated instance, the waves are staggered in relation to each other such that this alternately results in regions in which two plies 10 abut against each other and regions in which the two plies 10 form between themselves flow paths 14 for one medium or a plurality of media flowing through the installation element 1 while it is in use.

(7) In the regions of two plies 10 that abut against each other, these plies 10 are connected, for example, welded or glued or mechanically clipped, to each other by means of connection points 15 in sufficient number and appropriate distribution and density. The connected plies 10 then form an installation element 1 that has, e.g., the shape of a cuboid and is stable to such an extent that it forms a self-supporting body.

(8) The waves in the plies 10 can be aligned at a right angle to the front edge of the plies 10 that is facing the viewer or at a slanted angle thereto. Therein, the waves of neighboring plies 10 can extend in parallel or such that they intersect each other.

(9) FIG. 2 shows a detail of a ply 10 of the installation element 1 shown in FIG. 1 in an enlarged view. In the illustrated instance, the ply 10 comprises a plastic film comprising three layers 11, 12 and 13 and is produced by means of coextrusion.

(10) The central layer 11 comprises a customary plastic material which does not have to comprise special properties and, in essence, forms the supporting part of the ply 10. Here, plastic materials such as polypropylene (PP) or polyvinyl chloride (PVC) or polyethylene (PE) or polyvinylidene fluoride (PVDF) are particularly suitable.

(11) An outer layer 12, 13 which also comprises plastic is arranged on either side of the central layer 11, wherein however said plastic, contrary to the central layer 11, either comprises special application-specific properties by itself or is given application-specific properties by one or a plurality of additives.

(12) Depending on the use of the installation element 1, different application-specific properties are desired or required.

(13) When the installation element 1 is used in a cooling tower, for example, an antibacterial property of the outer layers 12, 13 is desired in order to prevent a multiplication and release of dangerous microorganisms, such as Legionella. An antibacterially acting additive that is suitable in this case are, for example, silver ions. What is often also desired in the same case of application, is a property of the outer layers 12, 13 of the plies 10, which lowers the surface tension of the liquids flowing across the plies 10, wherein said property can be achieved by means of one or a plurality of additives generating the corresponding property.

(14) When the installation element 1 is used as a sewage purification plant or fish farm installation element, it is desired that the outer layers 12, 13 of the three-layer coextruded plastic film comprise, as an application-specific property, a property that promotes a growth of pollutant degrading microorganisms. To achieve this, the property can, e.g., be a certain surface roughness for a firm hold of the microorganisms to be colonized and/or a nutrient supply that is limited in time and helpful at least in a starting phase of the colonization with microorganisms.

(15) When the installation element 1 is a mass transfer installation element, then the outer layers 12, 13 of the three-layer coextruded plastic film appropriately comprise, as an application-specific property, a property that increases the chemical resistance to the media entering into an exchange of materials in the installation element. Since the central layer of the three-layer coextruded plastic film is covered by the two outer layers and therefore does not come into contact with the possibly aggressive media, the central layer does not have to comprise an increased resistance.

(16) Finally, FIG. 3 is a schematic diagram of an extruder arrangement for coextrusion of three-layer plastic films for the plies 10 of the installation element 1.

(17) On the right of FIG. 3, two groups each with three storage tanks 21, 22 and 23 or 21, 22 and 23, respectively, are shown, which are used to provide plastic granules as well as additives for coextrusion of the films. The storage tanks 21, 22 and 23 are connected to a first screw conveyor 24 via conveying and metering equipment that is not shown here, with a plasticized plastic mass being produced in said screw conveyor 24. The storage tanks 21, 22 and 23 are connected to a second screw conveyor 24 via conveying and metering equipment that is not shown here either, with a plasticized plastic mass being produced in said screw conveyor 24 as well, wherein, if necessary, additives generating certain desired properties are added.

(18) The plasticized plastic masses are each supplied through a feed channel 25 or 25, respectively, to a common extrusion nozzle 26 by means of the screw conveyors 24 and 24, with the film forming the plies 10 with its three layers 11, 12 and 13 being generated by coextrusion. To achieve this, the plasticized plastic mass is, in the nozzle 26, supplied from the second screw conveyor 24 in the form of a flat strand to the upper side and lower side of the plasticized plastic mass that is released from the first screw conveyor 24 in the form of a flat strand as well, in order to generate in this manner the three-layer coherent film by the coextrusion thereof.

(19) After it has left the nozzle 26, the three-layer film is fed through a forming tool 27 to give the film the desired spatial structure, which is waviness in the illustrated instance.

(20) After the film web has cooled down and has been cut to film web sections, the plies 10 thus generated can be arranged one on top of the other and connected to each other to form the installation element 1 according to FIG. 1.

(21) As is apparent from the foregoing specification, the invention is susceptible of being embodied with various alterations and modifications which may differ particularly from those that have been described in the preceding specification and description. It should be understood that I wish to embody within the scope of the patent warranted hereon all such modifications as reasonably and properly come within the scope of my contribution to the art.

LIST OF REFERENCE NUMBERS

(22) TABLE-US-00001 Number Designation 1 Installation element 10 Plies of 1 11 Central layer of 10 12, 13 Outer layers of 10 14 Flow paths in 1 15 Connection points in 1 2 Extruder arrangement 21, 22, 23 First storage tanks 21, 22, 23 Second storage tanks 24, 24 Screw conveyors 25, 25 Feed channels 26 Extrusion nozzle 27 forming tool