Header for module of hollow fiber membranes and method of potting hollow fibers

• US 20060151373A1
• Filed: 10/25/2005
• Published: 07/13/2006
• Est. Priority Date: 10/26/2004
• Status: Active Grant

• Current Assignee: Zenon Technology Partnership
• Original Assignee: Zenon Environmental Incorporated (Veolia Environnement SA)
• Inventors: Szabo, Robert, Pedersen, Steven Kristian, Bakos, Gabor, Palinkas, Attila
• Granted Patent: US 7,393,486 B2
• Time in Patent Office: Days
• US Class Current: 210/321.610
• CPC Class Codes: B01D 63/0221 using a mould
• CPC Class Codes: B01D 63/0225 Multiple encapsulation layers
• CPC Class Codes: B01D 63/023 Encapsulating materials
• CPC Class Codes: B29C 45/14385 Coating a portion of a bundle of inserts, e.g. making brushes

Abstract

Hollow fiber membranes are potted by injection molding a thermoplastic material into a cavity containing the fibers. The cavity is formed in part by the interaction of a mold and a layer of an adhesive pre-applied to a bundle of the membranes.

Claims

1. A hollow fiber membrane module wherein the membranes are potted entirely in one or more thermoplastic materials that is/are solid at operating temperatures of the module but was/were applied at a temperature above its/their melting point.

2. The module of claim 1 wherein the thermoplastic materials comprise a hot melt type material in a first region and an injection molding polymer in a second region adjacent the first region, the injection molding material having a higher strength and melt temperature than the hot melt type material.

3. The module of claim 1 wherein at least one of the thermoplastic materials has a melt temperature of greater than 140°

C.

4. A method of potting hollow fiber membranes comprising the steps of:

a) forming a bundle of hollow fiber membranes, the membranes held together by a layer of adhesive material spaced from the ends of the membranes to provide a potting region between the layer of adhesive material and the ends of the membranes;

b) placing the bundle of membranes in a mold wherein the mold seals against the adhesive material to form a cavity surround the potting region;

c) injecting a liquid potting material into the cavity such that the potting material flows around the membranes;

d) solidifying the potting material in a seal with the membranes; and

,

e) removing the bundle of membranes from the mold.

5. The method of claim 4 wherein the potting material is a thermoplastic material that is made liquid by melting it and solidified by cooling it.

6. The method of claim 4 wherein the bundle is formed with a second layer of adhesive material on the opposite side of the potting region from the first material, and the cavity is formed in part by the second layer of adhesive material.

7. The method of claim 4 wherein the solidified potting material is cut across the fibers to provide a face of the potting material having open ends of the membranes flush with the face.

8. The method of claim 6 wherein the cavity is formed in part by the mold sealing against the second layer of adhesive material.

9. The method of claim 6 wherein the cavity is formed in part by the mold sealing against a permeate pan surrounding the ends of the membranes and the permeate pan sealing against the second layer of adhesive, the cavity arranged to also include a part of the surface of the walls of the permeate pan.

10. The method of claim 4 further comprising sealing the potting material to a permeate pan to form a fluid cavity in the permeate pan in communication with the ends of the membranes.

11. The method of claim 4 wherein the step of forming the bundle of membranes in step (a) of claim 4 further comprises providing a sheet of membranes and placing a layer of hot melt adhesive over the sheet of membranes.

12. The method of claim 11 further comprising a step of stacking a plurality of the sheets of claim 11 with their respective adhesive layers on top of each other.

13. A bundle of potted hollow fiber membranes comprising:

a) an array of hollow fiber membranes;

b) a layer of adhesive surrounding and connecting the membranes; and

,

c) a layer of a thermoplastic polymer sealed to and between the membranes,

wherein the layer of thermoplastic polymer extends from the layer of adhesive to a point at or spaced from the ends of the membranes.

14. The bundle of potted membranes of claim 13 further comprising a second layer of adhesive surrounding and connecting the membranes, the second layer of adhesive extending from the layer of thermoplastic polymer to a point at or near the ends of the membranes.

15. The bundle of potted membranes according to claim 13 wherein the layer of thermoplastic polymer is attached to a header pan to create a sealed fluid cavity within the permeate pan, the ends of the membranes being open to the permeate cavity.