Patent Publication Number: US-9889407-B2

Title: Device suitable for treatment of a fluid as well as a method and machine suitable for the manufacture of such a device

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a U.S. nationalization under 35 U.S.C. § 371 of International Application No. PCT/EP2013/056043 filed Mar. 22, 2013, which claims priority to Netherlands Patent Application No. 2008565 filed Mar. 29, 2012. 
     The invention relates to a device suitable for processing at least one fluid, which device is provided with at least one elongated foil that is formed in a number of reciprocating foil layers, wherein between two opposite foil layers a spacer is situated which is permeable at least parallel to the foil layers, said foil layers and interposed spacers extending spirally around a central axis, wherein folding lines between two foil layers extend substantially parallel to the central axis. 
     The invention further relates to a method and a machine suitable for the manufacture of such a device. 
     Depending on whether the foil is made of a heat-conducting foil, a membrane foil or a combination thereof, the device is suitable as a heat exchanger, a membrane filter, or a combination thereof. In a combination of, for example, a heat-conducting foil and a membrane foil, a spacer is situated between at least two foil layers of one of these foils. 
     In such a device, described in WO2010/011138 of the applicant and in the device shown in the  FIGS. 8-10 , the foil layers and the interposed mesh-like spacer extend spirally from a centerline of a cylindrical container to the exterior of the cylindrical holder. Because of the cylindrical shape, relatively large pressures may be applied. As is clearly visible in the  FIGS. 8-10 , the device shown in WO2010/011138 comprises a relatively large number of foil layers, which makes the manufacture of such a device relatively complex. 
     The invention aims to provide a device which combines the advantages of the known device and which is relatively simple to manufacture. 
     This objective is accomplished with the device according to the invention, in that each spacer is coupled at least at an end near the central axis with a support extending parallel to the central axis where, of the supports near the central axis, first supports are situated between two foil layers, which foil layers are connected to one another near the central axis, whereas second supports are situated between two successive first supports. 
     When spirally winding the foil layers around the central axis, the foil layers and the spacers can be firmly held by means of the supports that are coupled with the ends of the spacers near the central axis. The foil layers and the intervening spacers may subsequently be spirally wound around the central axis in a number of turns. 
     After the manufacturing of the device, a good support of the foil layers is obtained by the supports and the spacer. Moreover, the foil layers are shielded by the supports from possible sharp edges of the spacers. 
     An embodiment of the device according to the invention is characterized in that each spacer is coupled at both ends with a support. 
     This means that during the winding of the foil layers and the interposed spacers around the central axis, via the supports a tension force on the foil layers can be applied at the ends averted from the central axis, so that during winding the foil layers remain tightly tautened and do not undesirably curl. 
     After the manufacture of the device a cylindrical device is obtained, wherein a good support of the foil layers is obtained by the supports, both on the inside and the outside of the cylindrical device. 
     Another embodiment of the device according to the invention is characterized in that the support is tubular. 
     The tubular supports are hereby applicable as supply- and discharge channels. Moreover, in the tubular support a gripping means can simply be detachably attached for the fabrication of the device. 
     Another embodiment of the device according to the invention is characterized in that the support is provided with at least one aperture facing the spacer. 
     In this way, it is possible to use the support not only as gripping means during the manufacturing process, or as a support and shield for the spacer, but also simply as supply- or discharge channel of a fluid to be processed by the device. Via the aperture the fluid can flow from the space situated between the foil layers to the space bounded by the tubular support, and vice versa. 
     A further embodiment of the device according to the invention is characterized in that the aperture comprises an elongated slot extending parallel to the central axis, in which the end of the spacer is situated. 
     In this way a simple coupling of the spacer with the support is obtained. The aperture serves hereby for coupling of the spacer but also as passage for fluid. 
     Yet another embodiment of the device according to the invention is characterized in that the end of the spacer located the in tubular support is provided with a thicker portion that extends over at least part of the end. 
     Because of the thicker portion it is possible to link the spacer easily with the support, by sliding the thicker portion that is functioning as a tendon into the support, whereby the spacer extends through the slot. Here the thicker portion should be of such dimensions that it is not movable through the slot in radial direction. 
     A still further embodiment of the device according to the invention is characterized in that the elongated slot extends from a first end of the tubular support to a predetermined distance from the second end of the tubular support. 
     While fitting the spacer via the first end into the slot, a stop is formed by the second end, which simply prevents further movement of the tubular support in axial direction. 
     A still further embodiment of the device according to the invention is characterized in that at least the tubular supports near the central axis are positioned alternately with first and second ends to the axial ends of the spirally wound foil layers and spacers. 
     As a result, two sets of supports are formed as it were, in which a first set of supports is located in a first space that is separated by the foil layers from a second space in which the second set of supports is located. After the winding of the foil layers, the first ends of all the supports can for example be shut and the second ends can be connected to a fluid supply or drain. Here, the first space is accessible via a first axial side of the cylindrical device, whereas the second space is then accessible via a second side of the cylindrical device that is averted from the first axial side. 
     A still further embodiment of the device according to the invention is characterized in that at least the tubular supports near the central axis are alternately connected to a first and second fluid channel. 
     As a result, two sets of supports are formed as it were, in which a first set of supports is located in a first space that is separated by the foil layers from a second space, while the spaces are connected to different fluid channels. In a similar manner the tubular supports located at the averted side of the central axis can be connected to a third and fourth fluid channel. Here, the first and third fluid channels are connected to the first space, whereas the second and fourth fluid channels are connected to the second space. 
     A still further embodiment of the device according to the invention is characterized in that the first fluid channel is positioned at a first axial end of the spirally wound foil layers and spacers, whereas the second fluid channel is positioned at a second axial end of the spirally wound foil layers and spacers, the second end being averted from the first fluid channel. 
     As a result, the fluid channels are simply separated from each other and easily accessible from either side of the cylindrical device. In a similar manner, tubular supports located at a side averted from the central axis can also be alternately connected to two different fluid channels. The fluid channels that are connected to the same space, and located close to the central axis and distant from the central axis respectively, serve as supply- and discharge channels, or vice versa. 
     A still further embodiment of the device according to the invention is characterized in that the tubular supports, connected to the first respectively second axial end on the first respectively second fluid channel, are sealed at the second respectively first axial end. 
     Because of the sealed ends, it is effectuated in a simple manner that the fluid can only flow from the device at the desired axial side. 
     An embodiment of the device according to the invention is characterized in that the axial ends of the spirally wound layers of foil are sealed by means of a seal. 
     The entire axial side can herewith be easily sealed, with the exception of the desired passages in the ends of the supports, for example by means of a resin or a kit. 
     An embodiment of the device according to the invention is characterized in that a sealing foil portion of the foil is connected to a first foil layer, extending towards and being connected to the last foil layer and extending towards and again being connected to the first foil layer. 
     As a result, two enclosed spaces are formed that are completely separated from each other by the foil parts, which are completely sealed off in the circumferential direction of the cylindrical device by the sealing foil portion. 
     Only if the foil is a membrane foil, contact between the fluids in the different spaces is possible. 
     An embodiment of the device according to the invention is characterized in that the supports near the central axis are positioned around a central support tube. 
     The tubular supports lie alternately directly against the support tube or against the support tube with the intervention of the foil layer. 
     It is also possible that the support tube itself functions as a support for those spacers of which, in the case of individual supports, the supports would have lain directly against the support tube. 
     An embodiment of the device according to the invention is characterized in that at least near the central axis at least one additional support is situated between a first support and a second support, where, of the supports near the central axis, the first support is situated between two foil layers of a first foil, which foil layers of the first foil are connected to one another near the central axis, whereas the additional support, the two foil layers of a first foil as well as the first support are situated between two foil layers of a second foil, which foil layers of the second foil are connected to one another near the central axis. 
     The additional support is being used to guide near the central axis, the second foil around both the additional support, two foil layers of a first foil as well as the first support. In this manner an additional space is being created between the first and second foil for an additional fluid. If the additional support is tubular and provided with at least one aperture located between the first and second foil, the additional fluid can easily be guided into or out of the additional space through the tubular additional support. 
     It is possible to provide a number of additional supports between the first and the second support, whereby near the central axis a number of foils and, if desired an number of foil like spacers are wrapped around only the first support or around the first support and one additional support of around the first support and more additional supports. In all these cases near the central axis no foil need be wrapped around the second support. 
     The invention also aims to provide a method for the simple manufacture a device as described above. 
     This objective is accomplished with the method according to the invention in that a number of tubular supports extending parallel to one another are positioned between two rotatable elements on a central axis and are coupled therewith, wherein first ends of the spacers are coupled with the supports and the foil is wound in a reciprocating way alternately in foil layers around the first and second ends of the spacers, wherein the spacers and the foil layers extend substantially parallel to one another where, of the supports near the central axis, first supports are situated between two foil layers, which foil layers are connected to one another near the central axis, whereas second supports are situated between two successive first supports, whereupon the elements along with the foil layers and the spacers are rotated around the central axis, wherein the foil layers and the spacers are positioned spirally around the central axis. 
     With the method according to the invention, first a package of foil layers and spacers is formed that is extending substantially parallel to a plane. The package of foil layers and spacers can extend horizontally, in which case it can be easily carried by a carrier. The length of the carrier may simply be adjusted to the length of the package. However, it is also possible that the package extends vertically, in which case the foil layers and spacers are hanging on the disc-shaped elements, as it were. Here at a first side the supports, coupled with spacers, are coupled with the disc-shaped elements. Subsequently, the disc-shaped elements are rotated and the foil layers and the interposed spacers are wound to the orbit determined by the supports. Depending on the length of the foil layers and the thickness of the foil layers and spacers, a number of spiral windings will be formed. If desired, the disc-shaped elements may then be removed or be part of the final device. 
     An embodiment of the method according to the invention is characterized in that the axial ends of the spirally wound layers of foil are sealed by means of a seal. 
     The sealing is preferably done after the winding, because then an axial side can be sealed in one single operation. 
     The invention also aims to provide a machine by which, in a simple manner, a device as described above can be manufactured. 
     This objective is accomplished with the machine according to the invention, in that the machine is provided with at least two elements rotatable about a central axis, which elements are provided with fastening elements for detachably coupling of tubular supports between the elements, which machine is further provided with a substantially horizontally extending carrier and at least one foil roll holder that is movable in and opposite to the direction facing the central axis, relative to the carrier. 
     In this manner a foil layer can be positioned step by step, a support with an spacer coupled therewith can be placed on the foil layer and detachably connected to the disc-shaped elements, again a foil layer can be positioned etc., during which the foil roll holder is reciprocating over the spacers, and the disc-shaped elements are rotated each time after the application of a foil layer through an angle which is equal to 360 degrees, divided by the number of supports. 
     An embodiment of the machine according to the invention is characterized, in that the foil roll holder is moveable between the disc-shaped elements from one side of the central axis to the other side of the central axis and vice versa. 
     This allows the foil layer to be easily wrapped around the support and a fold line to be formed. For this purpose, a new support with spacer is connected to disc-shaped elements at the moment that the foil roll holder is positioned at a distance from the already-formed foil layers with interposed spacers, after which the foil roll holder is moved across the spacer to the end averted from the central axis of the spacer. 
    
    
     
       The invention will be further explained with reference to the accompanying drawings, in which: 
         FIGS. 1A-1E , show side views of a machine according to the invention, which is suitable for the manufacture of a device according to the invention, wherein the machine is shown in different processing positions; 
         FIGS. 2A and 2B  show a top view and side view of a spacer of a device according to the invention; 
         FIGS. 3A-3C , respectively, show a side view, a cross-sectional view and an enlarged cross-sectional view of a support of a device according to the invention; 
         FIGS. 4A-4C , respectively, show a top view, side view and enlarged view of a spacer shown in  FIGS. 2A and 2B , which is coupled with the supports illustrated in  FIGS. 3A-3C ; 
       FIGS.  5 A 1  and  5 A 2 - 5 H 1  show side views and rear views illustrating a part the machine shown in the  FIGS. 1A-1E , and of the device according to the invention, at various steps during the execution of the method according to the invention; 
         FIG. 6  shows schematically an enlarged side view of a part of the machine shown in the  FIGS. 1A-1E , and of the devices according to the invention, at one step during the execution of the method according to the invention; 
         FIG. 7  schematically shows the course of the foil and the position of the spacers in a device according to the invention; 
         FIGS. 8A-8D , respectively, show a cross-section with only the supports and the foil layers, a cross-section with only the supports and spacers, a cross-section with the supports, the foil, as well as spacers and a perspective, partially cut away view of a device according to the invention; 
         FIGS. 9A-9B and 10A-10B  are front views and side views of an alternative embodiment of a part of a device according to the invention, shown respectively during and after the manufacturing process; 
         FIGS. 11A-11B and 12A-12B  are front views and side views of an alternative embodiment of a part of a device, with dual foil layers according to the invention, shown respectively during and after the manufacturing process. 
         FIGS. 13A and 13B  are a schematic view and a side view showing the course of foils and the position of the spacers of another alternative embodiment of a device according to invention; 
         FIG. 14  is a schematic view showing the course of foils and the position of the spacers of another alternative embodiment of a device according to invention; 
         FIG. 15  is a side view and a schematic view showing the course of foils and the position of the spacers of another alternative embodiment of a device according to invention. 
     
    
    
     In the Figures, like parts are provided with the same reference numerals. 
       FIGS. 1A-1E  show side views of a machine  1  according to the invention, which is suitable for the manufacture of a device according to the invention. The machine  1  is provided with at least two disc-shaped elements  3 , rotatable about a centerline  2 . Each disc-shaped element  3  is provided with passages  5  situated on a circle  4  having a diameter d. The number of passages  5  is at least equal to the number of six supports  6  that the device  7  to be manufactured should include on a side facing the central axis  8 . During the manufacture of the device  7 , the central axis  8  coincides with the centerline  2  of the disc-shaped elements  3 . With the exemplary embodiment displayed in  FIGS. 5A - 5 H 1 , the device  1  comprises six supports  6  on a side facing the central axis  8 . The six passages  5  are hereby situated at an equal distance from each other on the circle  4 . The disc-shaped elements  3  are situated in axial direction at a distance from one another, which preferably corresponds to the width of the wrapping foil. The apparatus  1  is further provided with a substantially horizontally extending carrier  9 , substantially extending at the level of the centerline  2 . The carrier  9  is provided with two guides  10 , extending parallel to each other, transversely to the centerline  2  and which are situated on both sides of the two disc-shaped elements  3 . Over the guides  10  are two foil roll holders  11 ,  12  translatable in a direction and opposite a direction to the one facing centerline  2 , indicated by arrow P1. In each foil roll holder  11 ,  12  a roll  13 ,  14  with foil is situated, which rolls  13 ,  14  are rotatable around centerlines  15 ,  16  with respect the foil roll holder  11 ,  12 , for the unwinding of the foil from the roll  13 ,  14 . 
     The operation of the device  1  will be explained further with reference to the FIGS.  5 A 1 - 5 H 1 . 
       FIGS. 2A and 2B  show a top view and side view of a spacer  17  of a device  7  according to the invention. The spacer  17  includes a mesh-shaped layer  18  which is formed by two sets of plastics threads  19 ,  20  which each enclose an angle of preferably 15-45 degrees with the longitudinal side  22  of the spacer  17 , and which cross each other. The wires  19 ,  20  are preferably 0.5 to 2.5 mm thick. The mesh-shaped layer  18  is therefore 1 to 5 mm thick, in particular in the places where the wires  19 ,  20  cross each other. When flowing through the mesh-like layer  18 , the flow length is substantially the same everywhere; there are no preferred currents and there are no variable pressure drops. Such a mesh-like layer  18  is also known from NL1035752 of the applicant, and will, therefore, no further be explained. The spacer  17  of the device  7  according to the invention is further provided with thicker portions  21 , which are connected with the short sides  23  extending transverse to the longitudinal sides  22 . The thicker portions  21  have a thickness that is such, that the thickness of the short side  23  at the location of the thicker portion is greater than the thickness of the mesh-like layer  18 . The thicker portions  21  extend only over a part of the short side  23 , so that a fluid can flow at least between the thicker portions  21 . With the exemplary embodiment shown  FIG. 2A , each short side  23  comprises three thicker portions  21 , which are situated at a regular distance from each other. The thicker portions  21  can be made of the same material as the wires  19 ,  20 , or may be made of a different material. It is even possible to produce the thicker portions of a material that, after the manufacture of the device  7 , dissolves in the fluid during use of the device  7 , so that the thicker portions  21  are only present during and shortly after the manufacturing process. Such a soluble material is, for example, a medicinal soluble suture such as catgut or material of polylactic acid or of gelatin, salt, sugar, etc. With a soluble material, the thicker portion  21  may also extend over the entire short side  23 . 
       FIGS. 3A-3C  show respectively a side view, a cross-section and an enlarged cross-section of a support  6  of a device  7  according to the invention. 
     The support  6  is tubular and is provided with an elongated slot  24 , extending in axial direction. The slot  24  extends from a first end  25  of the support  6  up to a predetermined distance from the second end  26 . The width of the slot  24  in the tangential direction is smaller than the thickness of the spacer  17  at the location of the thicker portion  21 , but larger than the thickness of the mesh-like layer  18 . 
       FIGS. 4A-4C  show, respectively, a top view, a side view and an enlarged view of a spacer  17  connected to support  6 . For the connection of the spacer  17  with the support  6 , the short side of the spacer  17  is inserted into the first end  25  of the tubular support  6 , whereas the thicker portions  23  are positioned in the tubular support  6  while the mesh-shaped layer  18  extends through slot  24 . Near the second end  26 , a further movement of the mesh-like layer  18  is prevented by the end  27  of the slot  24 . The end  27  of the slot  24  forms a stop for the mesh-like layer  18 . If it is preferred to stretch the mesh-shaped layer  18  over the entire length of the support  6 , the mesh-shaped layer  18  near the second end  26  of the support  6  preferably has a notch (not shown) so that at the location of the notch the mesh-like layer  18  is not situated within the support  6 . 
     With the spacer  17 , depicted in the  FIGS. 4A-4B , both short sides  23  are each situated within a support  6 . 
     FIGS.  5 A 1  and  5 A 2 - 5 H 1  show side and rear views of a part of the machine  1  shown in  FIGS. 1A-1E , and of the device  7  according to the invention, at various steps during the execution of the method according to the invention. 
     The manufacture of a device  7  according to the invention is as follows. 
     Depending on the type of device  7  one wishes to manufacture, a roll or rolls  13 ,  14  of a heat-conductive foil, a membrane foil or combination thereof is placed in the foil roll holders  11 ,  12 . 
     The foil roll holders  11 ,  12  are placed in an initial position at the left-hand side of the carrier  9  that is averted from the disc-shaped elements  3 . The distance between the initial position of the foil roll holders  11 ,  12  and the centerline  2  corresponds hereby approximately to the length of the foil layers to be formed and of the spacers  17 . Subsequently, the foil roll holders  11 ,  12  are moved in the direction indicated by the arrow P1, where the foil of the roll  13 ,  14  or rolls  13 ,  14  is unwound, and a first foil layer  29  is formed, which is supported by the carrier  9 . The foil roll holders  11 ,  12  are moved beyond the central axis  2 , to the position shown in  FIG. 1   c.    
     Between the disc-shaped elements  3 , a supporting tube  28  is located, with a diameter that is equal to the diameter d of the circle  4  minus the diameter of the tubular support  6 . Next, a first support  6  is positioned between the disc-shaped elements  3 , wherein the passages  5  are located in line with the tubular support  6 . In the passages  5  and in the support  6  fastening elements will then be mounted, such as for example a bolt or pin, as a result of which the support  6  is detachably connected to the disc-shaped elements  3 . The support  6  is preferably located at the height of the carrier  9  between the initial position of the foil roll holders  11 ,  12  and the centerline  2 . With the support  6  a spacer  17  has already been coupled, which is also provided with a support  6  at an end that is averted from the first support  6 . The spacer  17  abuts here against the first foil layer  29  ( FIG. 1C ,  5 B 1 ,  5 B 2 ). 
     Thereafter, the foil roll holders  11 ,  12  are moved in the direction opposite to arrow P1, while the foil of the roll  13 ,  14  is unwound, and a second foil layer  29  is applied on the spacer  17 . The foil is here wrapped around the support  6 , whereby a folding line is formed by the support  6 , which extends parallel to the centerline  2 . The foil roll holders  11 ,  12  are moved to the initial position ( FIG. 1E ). The disc-shaped elements  3  will now be rotated in a direction indicated by arrow P2 through an angle that is equal to 360 degrees, divided by the number of supports  6  to be mounted on the circle  4 . With the illustrated example, there are six supports and so the angle will be 60 degrees. 
     Subsequently, a second support  6  is positioned between the disc-shaped elements  3 , wherein the passages  5  are located in line with the second support  6 . In the passages  5  and in the second support  6  then fastening elements are mounted, so that the second support  6  is detachably connected to the disc-shaped element  3 . The second support  6  is preferably located at the height of the carrier  9 , between the initial position of the foil roll holders  11 ,  12  and the centerline  2 . With the second support  6  a spacer  17  has already been coupled, which is also provided with a support  6  at an end that is averted from the second support  6  (FIG.  5 C 1 ,  5 C 2 ). The spacer  17  abuts here against the second foil layer  29 . 
     The above-indicated steps of applying a foil layer  29 , the rotation of the disc-shaped elements, the application of the supports and spacer, the application of a foil layer  29  etc. will be repeated so long until six spacers  17  and therewith connected supports  6  are coupled with the disc-shaped elements  3 , and are located between the foil layers (FIG.  5 D 1 ,  5 F 2 ,  6 ). All foil layers and spacers  17  extend here parallel to one another and to the carrier  9 . As is clearly visible in  FIG. 6 , of the supports  6  located near the centerline  2 , first plurality of supports  6  is situated between two foil layers  29 , which foil layers are connected with one another near the centerline  2 . The foil is wrapped about each of this first plurality of supports. Also is further clearly visible in  FIG. 6  that, of the supports  6  close to the centerline  2 , a second plurality of supports  6  is situated between two successive supports  6  of the first plurality of supports  6 . No foil has been wrapped around these supports  6 . Looking in circumferential direction of the support tube  28 , there is foil wrapped around the one support  6  and no foil wrapped around the next support  6 . 
     In order to keep the relatively thin foil layers tight, weights can be hung for instance to the supports  6  that are situated on a side averted from centerline  2 , so that the spacers  17  and thus also the wrapped around foil layers are held straight. It is also possible to apply a tension in other ways. 
     The disc-shaped elements  3  are then rotated about the centerline  2 , whereby the entire package of foil layers  29  and spacers  17  are wound spirally around the support tube  28 , until the supports  6  that are situated on a side averted from the centerline  2  abut against the spirally wound package. The disc-shaped elements  3  serve here as guiding for the foil layers  29  and the spacers  17 . Because the lengths of the foil layers  29  are substantially equal, the supports  6  that are located at the exterior of the cylindrical device  7  will be situated at a greater distance from one another than the interior supports  6 , but the mutual distance between the outer supports will substantially be equal (see FIGS.  5 G 1 ,  5 G 2 ). 
     The first and last layers of foil are preferably longer, so that after winding, the outer foil layers can be connected with each other by welded or glued joints  32 , and that for example the last foil layer can be wrapped around the entire wound module. 
     Schematically, the foil layers  29  and the spacers  17  are situated in the manner illustrated in  FIG. 7 , wherein the foil layers  29  form a separating layer between the first space  30  and a second space  31 . In this schematic representation the foil layers  29  are not spirally wound, for the sake of clarity, and the foil layers  29  do not abut against the spacers  17  and the supports  6 . The number of supports in  FIG. 7  amounts to two times twelve, so twenty-four. 
     During the mounting of the supports  6 , the supports of the one spacer  17  are oriented with the first end towards the first axial side of the cylindrical device  7 , whereas the next spacer  17  is oriented with the first end towards the second axial side of the cylindrical device  7 . 
     After the formation of the cylindrical device  7 , the fastening elements are removed from the disc-shaped elements  3 , after which the cylindrical device  7  can be taken from between the disc-shaped elements  3 . 
       FIGS. 8A-8D  show cross-sectional views and a perspective view of a device according to the invention with four supports  6  located on the inside, and four supports  6  located on the outer side.  FIGS. 8A and 8B  are parts of the entire device  1  shown in  FIG. 8C . In  FIG. 8A , the spacers  17  are omitted, whereas in  FIG. 8B  the foil is omitted, so that the Archimedes-spiral gradient is clearly visible. If desired, the support tube  28  can be removed after the manufacture of the device  1 , so that the entire central space can be used as a supply or drainage. 
     The relationship between the length L of the spacers  17 , the number of windings N, the inner diameter d, the number of spacers M and the thickness of the spacer m is approximately equal to: 
     
       
         
           
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     The relationship between the inner diameter d, the final diameter D, the number of spacers M, the length of the spacers L and the thickness of the spacer m is approximately equal to: 
     
       
         
           
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     Both axial sides are now provided with a seal, such as a resin or a kit. Because of the seal, the longitudinal sides of the foil layers  29  and the spacers  17  are connected to on another and the first ends  25  of the supports  6  are closed. 
     Then the second ends are opened again and the second ends of the inner supports  6  on the first axial side are connected to a first fluid channel, the second ends of the inner supports  6  on the second axial side are connected to a second fluid channel, the second ends of the outer supports  6  on first axial side are connected to a third fluid channel and the second ends of the outer supports  6  on the second axial side are connected to a fourth fluid channel. 
     The first fluid channel is in connection with the third fluid channel via the first space  30  bounded by the foil layers  29 , whereas the second fluid channel is in connection with the fourth fluid channel via the second space  31  bounded by the foil layers  29 . 
     The tubular supports  6  have a number of functions, such as attachment means for the spacers during manufacture, as supply- and discharge channel for the fluids to be processed, as protection of the foil against sharp edges of the spacers and for the creation of a homogeneous, smooth flow in the spacer. 
       FIGS. 9A-9B and 10A-10B  show views of an alternative embodiment of a part of a device according to the invention, wherein the supports  106  are not tubular and wherein the supply and discharge of fluid to and from the device subsequently can not be performed by the supports  106 . To still be able to access the space between the foil layers  29 , a plastic pouch  118  is attached around one side of the mesh-like spacer  117 , which partially covers a longitudinal side of the spacer  117 . After winding, the axial ends of the device are provided with a seal, such as a resin layer  119 . This resin layer  119  closes the gaps between the longitudinal sides of the foils  29  and the spacers  117  entirely (see  FIGS. 9A and 9B ). 
     Then, a slot  120  is provided in the resin layer  119  at the location of the plastic bag  118 , for example by milling. By this procedure the plastic bag  118  is partially removed and access is gained to the side  121  of the spacer  117 , via which side  121  fluids can be supplied or discharged. In the embodiment illustrated in the  FIGS. 9A-9B , a similar plastic bag is attached both bottom left and top right, so that a supply and discharge channel is realized. 
       FIGS. 11A-11B and 12A-12B  show views of an alternative embodiment of a part of a device according to the invention, wherein the supports  6  are tubular and in which two foils are wrapped around the supports  6 . In this embodiment, four spaces are formed. Via the tubular supports fluid may be supplied to two separate spaces or discharged from these spaces. Between the foils also two spaces are formed. To access these two spaces, a relatively small local spacer  217 , provided with a plastic pouch  118 , is attached during manufacture near the supports  6  between two foils, in the same manner as is illustrated in the embodiment in the  FIGS. 9A-9B . 
     After winding, the axial ends of the device are provided with a seal, such as a resin layer  119 . This resin layer  119  closes the gaps between the longitudinal sides of the foils and the spacers  17 ,  217  entirely (see  FIGS. 11A and 11B ). 
     Then a slot  120  is provided in the resin layer  119  at the location of the plastic bag  118 , for example by milling. By this procedure the plastic bag  118  is partially removed and access is gained to the side  121  of the spacer  217 , via which side  121  fluids can be supplied or discharged. 
       FIGS. 13A and 13B  are a schematic view and a side view of another alternative embodiment of a device  300  according to invention. 
     In the schematic representation in  FIG. 13A  the foil layers and spacers are not spirally wound and are spaced apart, for the sake of clarity. 
     The device  300  comprises near the central axis  8 , first tubular supports S4, second tubular supports S1 and additional tubular supports S2, S3. On a side avert of the central axis  8 , the device  300  comprises tubular supports S5, S8 and additional tubular supports S6, S7. A spacer  301  extends between and is connected to the supports S1, S5 and to the supports S4, S8 in the same manner as described above. 
     The additional supports S2, S3, S6, S7 are tubular and provided with a longitudinal aperture  302 . 
     In  FIG. 13A  the supports S4 and additional supports S2, S3 are shown on the same horizontal level, for the sake of clarity. However, in the device  300  as shown in  FIG. 13B  it can be seen that near the central axis  8  all supports and additional supports are located on a circle  303  in the order S1, S2, S3, S4, S1, etc. The same holds true for the supports S5, S6, S7, S8, S5 etc. which are located near the outside of the device  300 . 
     The device  300  is provided with a first foil  304 , a first foil like spacer  305 , a second foil  306 , a second foil like spacer  307  and a third foil  308  extending parallel to each other but each wrapped around the supports S1, S4, S5, S8 and the additional supports S3, S4, S6, S7 in a different way. 
     As can be seen in  FIG. 13A , the first foil  304  extends around the support S5 and the additional supports S6, S7 on the outer side of the device  300  and around the support S4 on the inner side of the device  300 . 
     The first foil like spacer  305  extends around the support S5 and the additional supports S6, S7 on the outer side of the device  300  and around the additional support S3 and the support S4 on the inner side of the device  300 . 
     The second foil  306  extends around the support S5 and the additional support S6 on the outer side of the device  300  and around the additional support S3 and the support S4 on the inner side of the device  300 . 
     The second foil like spacer  307  extends around the support S5 and the additional support S6 on the outer side of the device  300  and around the additional supports S2, S3 and the support S4 on the inner side of the device  300 . 
     The third foil  308  extends around the support S5 on the outer side of the device  300  and around the additional supports S2, S3 and the support S4 on the inner side of the device  300 . 
     The device  300  is made in the same manner as the device described above, except that five foil roll holders are being used, one for each of the foils  304 ,  306 ,  308  and the foil like spacers  305 ,  307 . 
     No foils are wrapped around the supports S1 and S8. If desired a complete set of foils  304 - 308  may be wrapped around the whole stack of foils, supports and additional supports to connect the ends of the foils to each other. 
     By wrapping the foils  304 ,  306 ,  308  and the foil like spacers  305 ,  307  in this manner, three separate spaces  300 ,  310 ,  311  are created in which different fluids can be guided to be processed. The foils  304 ,  306 ,  308  can be membranes or heat exchange layers. 
       FIG. 14  is a schematic view of another alternative embodiment of a device  320  according to invention. The device  320  differs form the device  300  in the way the foils  304 ,  306 ,  308  and the foil like spacers  305 ,  307  are wrapped around the supports S1, S4, S5, S8 and the additional supports S2, S3, S6, S7. 
     As can be seen in  FIG. 14 , the first foil  304  extends around the support S5 and the additional supports S6, S7 on the outer side of the device  320  and around the support S4 on the inner side of the device  320 . 
     The first foil like spacer  305  extends around the support S5 and the additional support S6 on the outer side of the device  320  and around the support S4 on the inner side of the device  320 . 
     The second foil  306  extends around the support S5 and the additional support S6 on the outer side of the device  320  and around the additional support S3 and the support S4 on the inner side of the device  320 . 
     The second foil like spacer  307  extends around the support S5 on the outer side of the device  320  and around the additional support S3 and the support S4 on the inner side of the device  320 . 
     The third foil  308  extends around the support S5 on the outer side of the device  320  and around the additional supports S2, S3 and the support S4 on the inner side of the device  320 . 
     The device  320  is made in the same manner as the device  300  described above. 
     By wrapping the foils  304 ,  306 ,  308  and the foil like spacers  305 ,  307  in this manner, three separate spaces  321 ,  322 ,  323  are created in which different fluids can be guided to be processed. The foils  304 ,  306 ,  308  can be membranes or heat exchange layers. 
       FIG. 15  is a schematic view of another alternative embodiment of a device  330  according to invention. The device  330  differs form the devices  300 ,  320  in the way the foils  304 ,  306 ,  308  and the foil like spacers  305 ,  307  are wrapped around the supports S1, S4, S5, S8 and the additional supports S2, S3, S6, S7. 
     As can be seen in  FIG. 15 , the first foil  304  extends around the support S5 and the additional supports S6, S7 on the outer side of the device  330  and around the support S4 on the inner side of the device  330 . 
     The first foil like spacer  305  extends around the support S5 and the additional supports S6, S7 on the outer side of the device  330  and around the support S4 on the inner side of the device  330 . 
     The second foil  306  extends around the support S5 and the additional support S6 on the outer side of the device  330  and around the additional support S3 and the support S4 on the inner side of the device  330 . 
     The second foil like spacer  307  extends around the support S5 on the outer side of the device  330  and around the additional supports S2, S3 and the support S4 on the inner side of the device  330 . 
     The third foil  308  extends around the support S5 on the outer side of the device  330  and around the additional supports S2, S3 and the support S4 on the inner side of the device  330 . 
     The device  330  is made in the same manner as the devices  300 ,  320  described above. 
     By wrapping the foils  304 ,  306 ,  308  and the foil like spacers  305 ,  307  in this manner, three separate spaces  331 ,  332 ,  333  are created in which different fluids can be guided to be processed. The foils  304 ,  306 ,  308  can be membranes or heat exchange layers. 
     The outer surface of the cylindrical device  7  may be provided with a reinforcement layer, such as a tape. 
     The number of windings is preferably 1 to 7. The number of tubular supports is preferably even, is at least 4 and is for instance between 4 and 24. The inner diameter is preferably between 50 and 90 mm. The outer diameter is preferably between 250 and 500 mm. The thickness of the foil is preferably between 50 and 120 micrometers. The thickness of the spacer is preferably between 1 and 3 mm. The width of the foil and spacer is preferably between 300 and 1000 mm. The length of the spacer is preferably between 0.8 and 6 meters. 
     It is also possible to provide the slot in the tubular support with barbs, which can be coupled to the spacer for the attachment of the spacer to the tubular support. 
     It is also possible to tie the spacer to the support with the aid of wires, whereby the wires extend through apertures in the mesh-shape or extend through the spacer. 
     It is also possible to apply the tension force on the spacers during the winding process. The material of the foil and spacer may be any material suitable for the desired application of the device. 
     It is also possible during manufacture to first apply a spacer on the carrier and then the first foil layer. The spacer is firmer and glides more easily over the carrier than the foil layer. 
     It is also possible to provide the elements with a different shape, instead of the disc-shaped elements. 
     It is also possible that the disc-shaped elements are part of the final device. 
     It is also possible to apply a gearwheel-like element, instead of a disc-shaped element with passages, whereby the supports are clamped between the teeth of the gearwheel-like element. 
     It is also possible to provide only one or none of the spacers with a thicker position  21  but only slide the spacers into the slots. 
     It is also possible that both ends of the tubular support are closed, where by a modified form of the slot in the support, the application of the spacer and the supply and discharge of fluid are possible.