Frameless array of hollow fiber membranes and module containing a stack of arrays

• US 5,104,535 A
• Filed: 08/17/1990
• Issued: 04/14/1992
• Est. Priority Date: 08/17/1990
• Status: Expired due to Fees

• Current Assignee: Zenon Environmental Incorporated
• Original Assignee: Zenon Environmental Incorporated
• Inventors: Lipski, Christopher J., Cote, Pierre L., Maurion, Roger P.
• Primary Examiner(s): Sever, Frank
• Application Number:
  US07/569,405
• Time in Patent Office: 606 Days
• Field of Search: 210/321.89, 210/321.6, 210/321.64, 210/321.72, 210/321.78, 210/321.79, 210/321.8, 210/321.87, 210/321.88, 210/500.23
• US Class Current: 210/321.8
• CPC Class Codes: B01D 63/021 Manufacturing thereof
• CPC Class Codes: B01D 63/022 Encapsulating hollow fibres
• CPC Class Codes: B01D 63/0231 using supporting structures, e.g. filaments for weaving mats
• CPC Class Codes: B01D 63/04 comprising multiple hollow fibre assemblies
• CPC Class Codes: B01D 63/043 with separate tube sheets

Abstract

A module is disclosed for use as a membrane device, comprising, a shell with fluid couplings removably affixed to each of its ends. A stack is formed with plural frameless arrays of hollow fibers of selectively permeable material. Each array is free of any means to support the fibers intermediate split-clip headers in which the fibers are held near their opposite ends. The split-clip headers are identical. Each has longitudinal, laterally spaced apart grooves in the inner surfaces of upper and lower sections from which the split-clip header is formed. The grooves in each section placed one upon the other, together form a through-passage in which a terminal portion of a fiber is snugly embraced. The fibers lie in parallel spaced-apart relationship in a plane substantially orthogonal to the direction of flow of said feedstream. The fibers of one array lie transversely to those of another array. The stack is disposed longitudinally within the shell and comprises plural split-clip headers which when laminated, one to another, define a fluid-tight conduit with open ends through which a feedstream is flowed transversely over the fibers. The bores of the fibers are in open fluid communication with the permeate zone in the shell.

Claims

1. A module for use as a membrane device constructed without potting hollow fibers of selectively permeable material, comprising,

a shell having two ends;

a pair of end closures with fluid couplings removably affixed to each of said ends of said shell;

a stack of plural frameless arrays of said hollow fibers;

said fibers being held near their opposite ends in identical split-clip headers each having a through-passage adapted snugly to embrace terminal end portions of said fibers so that said fibers lie in parallel spaced-apart relationship in a plane substantially orthogonal to the direction of flow of said feedstream, and the fibers of one array lie transversely to those of another array;

said stack disposed longitudinally within said shell, said stack comprising plural split-clip headers which are laminated one to another so as to define a fluid-tight conduit having open ends through which a feedstream is flowed transversely over said fibers into a concentrate zone, the bores of said fibers being in open fluid communication with a permeate zone in said shell;

means for feeding said feedstream to said shell so that it flows over said hollow fibers under a sufficient driving force to effect the separation desired and yield a permeate, and separately, a concentrate;

means to remove said permeate from said permeate zone; and

,

means to remove said concentrate from said concentrate zone.

2. The module of claim 1 wherein said array comprises,

(i) a pair of identical split-clip headers longitudinally spaced apart by the length of said fibers, each said split-clip header comprising an upper and a lower laminar section having a width sufficient to negate damage to terminal portions of said fibers when subjected to a drag force produced by a transversely flowing feedstream;

(ii) the number of said grooves being equal to the number of said hollow fibers, with each groove having an arcuate profile adapted to snugly embrace a corresponding arcuate portion of one of said hollow fibers near one of its ends;

(iii) said grooves in said lower section being spaced apart with the same spacing as those in said upper section, so as together to embrace each one of said one hollow fibers near its one end;

(iv) means for bonding said sections and said terminal portions held between said sections, in fluid-tight relationship; and

,

(v) means for interfitting said array with another array in a generally planar configuration, said means being provided in each said split-clip header.

3. The module of claim 2 wherein said split-clip headers have a thickness in the range from about 1.8 to about 5 times the outside diameter of said fibers, and said upper and lower sections are formed from flexible laminar synthetic resinous stock.

4. The module of claim 2 wherein said fibers are laterally spaced apart in grooves in each section of said split-clip header, and the grooved portion of one section is in mirror image relationship with that of the other.

5. The module of claim 2 wherein said array includes at least one tension cord having substantially the same length as said fibers to provide reinforcing for said split-clip header and support for fibers in a next adjacent array, when said latter fibers are deflected during operation of said module.

6. The module of claim 1 wherein said hollow fibers have an outside diameter in the range from about 20 microns to about 3 mm, and a wall thickness in the range from about 5 microns to about 1 mm.

7. The module of claim 6 wherein each array of fibers discharges said permeate into said permeate zone in opposite directions, so that the arrays in said stack discharge permeate in four directions into said shell in four directions, each at right angles to another.

8. The module of claim 7 wherein each said section of said split-clip header is formed from a thermoplastic synthetic resinous material.

9. The module of claim 1 wherein said stack is mounted in said shell on mounting means upon which each said array of fibers is tensionable to a preselected extent, and each array is free of means other than said split-clip header to support hollow fibers.

10. The module of claim 1 wherein said bonding means is provided by an adhesive, ultra-sound waves, a solvent weld, or dielectric heating.

11. The module of claim 10 wherein the void fraction within said stack is in the range from about 25% to about 70%, and said fibers are held in said split-clip headers by terminal portions which range from about 4% to about 20% of the overall length of the fibers.

12. The module of claim 11 wherein at least some of said fibers in one array pressingly contact fibers from a next adjacent array, so as to provide support for each other during flow of fluid through said module.

13. The module of claim 11 wherein said fibers are essentially free from contact, one with another, in each array, and from one array to another, except during flow of fluid through said stack under flow conditions sufficient to produce a sag in said fibers.

14. An array of hollow fibers for use in a membrane device constructed without potting hollow fibers of selectively permeable material, comprising,

(i) a pair of identical split-clip headers longitudinally spaced apart by the length of said fibers, each said split-clip header comprising an upper and a lower laminar section having a width sufficient to negate damage to terminal portions of said fibers when subjected to a drag force produced by a feedstream flowing transversely over said fibers;

(ii) plural longitudinal, laterally spaced apart grooves in each said section, the number of said grooves being equal to the number of said hollow fibers, with each groove having an arcuate profile adapted to snugly embrace a corresponding arcuate portion of one of said hollow fibers near one of its ends;

(iii) said grooves in said lower section being spaced apart with the same spacing as those in said upper section, so as together to embrace each one of said one hollow fibers near its one end;

(iv) means for bonding said sections and said terminal portions held between said sections, in fluid-tight relationship;

to form said array having a pair of split-clip headers, one of which is displaceable in any direction relative to the other; and

,

(v) means for interfitting said array with another array in a generally planar configuration, said means being provided in each said split-clip header.

15. The array of claim 14 wherein said fibers have an outside diameter in the range from about 20 microns to about 3 mm, and a wall thickness in the range from about 5 microns to about 1 mm.

16. The array of claim 14 wherein said fibers are free of any support means other than said split-clip headers.

17. The array of claim 14 wherein said split-clip headers fixedly confine opposed ends of at least one tension cord disposed in parallel relationship with said fibers so that said tension cord provides support for fibers in a next adjacent array.

18. The array of claim 14 wherein said upper and lower laminar sections are produced from a thermoplastic synthetic resinous material.

19. The array of claim 18 wherein said upper and lower laminar sections of thermoplastic synthetic resinous material are adhesively bonded to each other, and to said terminal portions of said fibers.

20. A method for securing plural hollow fibers in an array for a membrane device, without potting said fibers, said method comprising,

(i) training said plural fibers in parallel spaced apart relationship, into longitudinal, laterally spaced apart grooves provided in a first pair of opposed, longitudinally spaced apart laminar sections each having a width corresponding to the length of one terminal portion of a fiber to be secured in one groove;

(ii) placing a second pair of laminar sections, each having longitudinal, laterally spaced apart grooves therein, coextensively over said first pair so as to embrace each said terminal portion between the grooves of said laminar sections; and

, (iii) bonding said laminar sections with said fibers therebetween in fluid-tight relationship to secure said fibers in a split-clip header.

21. A method of using a fluid treating apparatus of hollow fiber type comprising the steps of:

providing a module for use as a membrane device constructed without potting hollow fibers of selectively permeable material, said module comprising,

a shell having two ends;

a pair of end closures with fluid couplings removably affixed to each of said ends of said shell;

a stack of plural frameless arrays of hollow fibers of selectively permeable material;

said fibers being held near their opposite ends in identical split-clip headers each having a through-passage adapted snugly to embrace terminal end portions of said fibers so that said fibers lie in parallel spaced-apart relationship in a plane substantially orthogonal to the direction of flow of said feedstream, and the fibers of one array lie transversely to those of another array;

said stack disposed longitudinally within said shell, said stack comprising plural split-clip headers which are laminated one to another so as to define a fluid-tight conduit having open ends through which a feedstream is flowed transversely over said fibers into a concentrate zone, the bores of said fibers being in open fluid communication with a permeate zone in said shell;

means for feeding said feedstream to said shell so that it flows over said hollow fibers under a sufficient driving force to effect the separation desired and yield a permeate, and separately, a concentrate;

means to remove said permeate from said permeate zone; and

,

means to remove said concentrate from said concentrate zone.

22. The method of claim 21 including separating a component from a feedstream having at least one other component therein, comprising,

(a) flowing said feedstream over said fibers in a direction essentially orthogonal to the plane in which said fibers lie;

(b) collecting that portion of said feedstream which permeates walls of said fibers into a permeate zone in said module and conducting said portion away from said permeate zone; and

,

(c) flowing concentrate which does not permeate said walls and remains in a feed zone in said module, away from said feed zone and out of said module.

23. The method of claim 21 including treating first and second fluids in said module, so that said second fluid, or a component from said second fluid is given up and added to said first fluid, said method comprising,

(a) choosing said fibers which are selectively permeable to said second fluid to be added, or to said component of said second fluid which component is to be added,

(b) flowing one of said fluids into said module, and over said fibers, essentially orthogonally to the plane in which said fibers lie under flow conditions chosen to incorporate a portion of the other of said fluids, or a component thereof;

(c) flowing said other of said fluids into said module and through said fibers under flow conditions chosen to give up a portion of said other fluid or a component thereof;

(d) collecting fluid which flows over said walls of said fibers and conducting it away, out of said module; and

,

(e) collecting fluid which flows through said fibers and conducting it away out of said module.