Submergible membrane modular filtration device having replaceable membrane elements

• US 20040188339A1
• Filed: 03/05/2004
• Published: 09/30/2004
• Est. Priority Date: 03/05/2003
• Status: Abandoned Application

• Current Assignee: Hydranautics (Nitto Denko Corporation)
• Original Assignee: Hydranautics (Nitto Denko Corporation)
• Inventors: Pearce, Graeme K., Schilling, Marco A., Hermanson, Christopher G., deWinter, Dirk M., Wilf, Mark, Murkute, Pravin, Bartels, Craig R.
• Application Number:
  US10/795,022
• Publication Number:
  US 20040188339A1
• Time in Patent Office: Days
• US Class Current: 210/321.8
• CPC Class Codes: B01D 2313/06 External membrane module supporting or fixing means
• CPC Class Codes: B01D 2313/125 Discharge manifolds
• CPC Class Codes: B01D 2313/13 Specific connectors
• CPC Class Codes: B01D 2313/21 Specific headers, end caps
• CPC Class Codes: B01D 2313/54 Modularity of membrane module elements
• CPC Class Codes: B01D 2315/06 Submerged-type; Immersion type
• CPC Class Codes: B01D 2321/185 Aeration
• CPC Class Codes: B01D 2321/2066 Pulsated flow
• CPC Class Codes: B01D 61/18 Apparatus therefor
• CPC Class Codes: B01D 61/20 Accessories; Auxiliary operations
• CPC Class Codes: B01D 63/02 Hollow fibre modules
• CPC Class Codes: B01D 63/021 Manufacturing thereof
• CPC Class Codes: B01D 63/0233 forming the bundle
• CPC Class Codes: B01D 63/024 with a single potted end
• CPC Class Codes: B01D 63/033 Specific distribution of fibres within one potting or tube-sheet
• CPC Class Codes: B01D 63/043 with separate tube sheets
• CPC Class Codes: B01D 65/00 Accessories or auxiliary operations, in general, for separation processes or apparatus using semi-permeable membranes
• CPC Class Codes: B01D 65/08 Prevention of membrane fouling or of concentration polarisation
• CPC Class Codes: C02F 1/444 by ultrafiltration or microfiltration

Abstract

A modular membrane filtration device is provided with replaceable membrane elements. The device is designed for ease of cleaning or replacing the membrane elements during filtration of a feed liquid to remove suspended solids. The cleaning may be effected by continuous aeration or by application of air as intermittent pressurized pulses. The device preferably has two headers, at least one of which is a permeate collection header having receptacles for a plurality of membrane elements, each of which is a potted hollow fiber membrane bundle. The potted hollow fiber membrane bundles are distinct entities which may be inserted into the receptacles, preferably in rows of circular slots, on the permeate collection header(s), and may be easily removed for maintenance, such as for replacement of the hollow fiber membrane elements.

Claims

1. A modular membrane filtration device for outside-in membrane filtration of a feed liquid containing at least one suspended solid, the device comprising at least one module comprising at least one header which is an integral permeate collection header having a plurality of receptacles for receiving a plurality of membrane elements, wherein each membrane element comprises at least one potted hollow fiber membrane bundle comprising a plurality of hollow fiber membranes oriented transverse to the at least one header, each membrane element having a separable connection between a potted end of the hollow fiber membrane bundle and one of the receptacles in the at least one permeate collection header, and wherein the separable connection provides a watertight hydraulic connection between the at least one permeate collection header and lumens in the hollow fiber membranes.

2. The modular membrane filtration device module according to claim 1, wherein the at least one module comprises two headers and at least some of the plurality of hollow fiber membranes has an overlength of about 0.2% to 20% of a distance between the two headers.

3. The modular membrane filtration device according to claim 2, wherein the overlength is greater than 5% to about 10%.

4. The modular membrane filtration device according to claim 1, wherein the at least one module comprises two headers spaced vertically or horizontally apart and wherein the device further comprises a rigid support connecting the two headers to maintain a fixed distance.

5. The modular membrane filtration device according to claim 1, wherein the at least one permeate collection header comprises at least one row of receptacles for receiving the plurality of membrane elements.

6. The modular membrane filtration device according to claim 1, wherein each of the receptacles has a shape selected from the group consisting of circular, oval, square, rectangular, and rhomboidal.

7. The modular membrane filtration device according to claim 1, wherein the modular device further comprises a releasable closure for detaching one of the membrane elements from one of the receptacles, such that when the element is detached, the closure hydraulically isolates the receptacle without the membrane element from the feed liquid.

8. The modular membrane filtration device according to claim 7, wherein the closure is selected from the group consisting of a valve and a spring loaded mechanism.

9. The modular membrane filtration device according to claim 1, wherein the modular device comprises a device for quick attachment or detachment of the membrane element from the plurality of receptacles.

10. The modular membrane filtration device according to claim 1, wherein the device comprises at least two permeate collection headers spaced apart in a parallel configuration, and further comprises at least one aeration diffuser having a plurality of apertures to supply a gas in outer proximity to the hollow fiber membranes.

11. The modular membrane filtration device according to claim 10, wherein the aeration tube is configured for continuous aeration and for application of air as intermittent pulses.

12. The modular membrane filtration device according to claim 10, comprising a plurality of aeration diffusers arranged adjacent a bottom of the at least one module.

13. The modular membrane filtration device according to claim 10, wherein the aeration diffusers comprise perforated aeration tubes arranged parallel to a longitudinal axis of the hollow fiber membrane bundle.

14. The modular membrane filtration device according to claim 13, wherein the perforated aeration tubes are arranged one inside each hollow fiber membrane bundle.

15. The modular membrane filtration device according to claim 10, wherein the at least one permeate collection header comprises at least two rows of receptacles and at least one open area between the at least two rows of receptacles for free flow of the feed liquid, and wherein the at least one open area contains at least one aeration diffuser.

16. The modular membrane filtration device according to claim 1, wherein the at least one module comprises two headers spaced horizontally apart in a parallel configuration with membrane elements extending between them, and further comprising at least one aeration diffuser arranged parallel to a longitudinal axis of at least one of the plurality of membrane elements and below the plurality of membrane elements.

17. The modular membrane filtration device according to claim 1, wherein the device comprises at least two modules each comprising two headers spaced vertically apart to form an upper and a lower header, and the at least two modules are stacked atop of one another to form a vertical column of modules such that an upper header of a first module lies beneath a lower header of a second module, and wherein the device defines outer faces.

18. The modular membrane filtration device according to claim 17, wherein the device comprises about two to eight modules.

19. The modular membrane filtration device according to claim 17, further comprising a shroud material covering the outer faces of the at least one module, wherein the shroud material surrounds the plurality of hollow fiber membranes and contains energy produced by aeration within a module volume confined by the shroud material.

20. The modular membrane filtration device according to claim 19, wherein the shroud material is selected from the group consisting of a porous material, a non-porous material, a woven material, a knit material, an extruded material, a rigid material, an elastic material, and a non-rigid material.

21. The modular membrane filtration device according to claim 1, wherein the device is submergible.

22. The modular membrane filtration device according to claim 21, wherein the device is submerged in the feed liquid and membrane filtration is effected by a vacuum created in the lumens of the hollow fiber membranes by a suction device.

23. The modular membrane filtration device according to claim 21, wherein the device is placed in a pressurized enclosure and membrane filtration is effected by pressure in the enclosure.

24. A modular membrane filtration device for outside-in membrane filtration of a feed liquid containing at least one suspended solid, the device comprising at least one module comprising at least one header which is an integral permeate collection header having a plurality of receptacles for receiving a plurality of membrane elements, wherein each membrane element comprises at least one potted hollow fiber membrane bundle comprising a plurality of hollow fiber membranes oriented transverse to the at least one header, each membrane element having a separable connection between a potted end of the hollow fiber membrane bundle and one of the receptacles in the at least one permeate collection header, and the separable connection provides a watertight hydraulic connection between the at least one permeate collection header and the lumens in the hollow fiber membranes, wherein the at least one module defines outer faces and comprises a shroud material covering at least one of the outer faces, wherein the shroud material surrounds the plurality of hollow fiber membranes and contains energy produced by aeration within a volume confined by the outer faces of the device.

25. A bundle connector for releasably connecting a bundle of hollow fiber membranes to a receptacle of a permeate collection header of a membrane filtration system, the connector comprising a sleeve for receiving one end of the hollow fiber bundle, an interior surface of the sleeve having at least one first surface irregularity for locking engagement with a potting material received in the sleeve to sealingly secure the hollow fiber bundle in the connector, an exterior surface of the sleeve having at least one sealing material to create a liquid-tight seal with a mating interior surface of the receptacle, and the exterior surface of the sleeve further having at least one second surface irregularity which cooperates with a complementary surface irregularity on the receptacle for releasably locking the connector in the receptacle to maintain the liquid-tight seal.

26. The bundle connector according to claim 25, wherein the first surface irregularity comprises at least one selected from the group consisting of axial extending ribs to resist rotation of the bundle in the connector, annular grooves to resist axial shifting of the bundle in the connector, longitudinally sloped wall surfaces to resist axial shifting of the bundle in the connector, undercut edges on an end of the sleeve to resist axial shifting of the bundle in the connector, and surface roughness to resist axial shifting and/or rotation of the bundle in the connector.

27. The bundle connector according to claim 25, wherein the connector has a circular outer cross-section, and the sealing material comprises at least one O-ring.

28. The bundle connector according to claim 27, wherein the exterior surface has at least one annular groove to receive and hold the at least one O-ring.

29. The bundle connector according to claim 25, wherein the at least one second surface irregularity comprises at least one hook-shaped outward protrusion having an inwardly facing groove to receive at least one complementary tab on an exterior surface of the receptacle.

30. The bundle connector according to claim 29, having at least two hook-shaped protrusions for engaging with a like number of the complementary tabs, the protrusions being equally spaced around a periphery of the connector.

31. The bundle connector according to claim 30, wherein the hook-shaped protrusions lock with the tabs by rotation of the connector in the receptacle.

32. The bundle connector according to claim 30, wherein the protrusions are located adjacent an end edge of the sleeve facing away from the end face of the fiber bundle.

33. The bundle connector according to claim 25, further comprising a tube adjacent the interior surface of the connector and lying in or on an exterior region of the potting material, the tube having a soft, non-abrasive surface facing the fiber bundle.

34. The bundle connector according to claim 33, wherein the tube comprises an elastomeric material and is selected from the group consisting of a mesh tube and a continuous tube.

35. The bundle connector according to claim 33, wherein the tube extends beyond the potting material to partially surround free fibers of the bundle.