Tubular membrane module

• US 5,227,063 A
• Filed: 03/30/1990
• Issued: 07/13/1993
• Est. Priority Date: 10/03/1989
• Status: Expired due to Term

• Current Assignee: Zenon Environmental Incorporated (Veolia Environnement SA)
• Original Assignee: Zenon Environmental Incorporated (Veolia Environnement SA)
• Inventors: Koehler, Paul B., Langerak, Robert W., Tonelli, Fernando A.
• Primary Examiner(s): Dawson, Robert A.
• Assistant Examiner(s): WALKER, WANDA LYNNE
• Application Number:
  US07/501,997
• Time in Patent Office: 1,201 Days
• Field of Search: 210/321.78, 210/321.87, 210/937, 210/457, 210/460, 210/484, 210/500.23, 55/158
• US Class Current: 210/321.78
• CPC Class Codes: B01D 63/063 on the inner surface thereof

Abstract

A tubular membrane module for example for use in ultrafiltration has a tubular shell made of standard PVC pipe provided with moulded PVC end fittings that are secured to the pipe by epoxy resin adhesive. A membrane tube within the shell extends between the end fittings and is secured by a similar adhesive in respective sockets within the end fittings. Each socket has a blind end that receives the end portion of the membrane tube so that the tube is protected from shear effects due to fluid entering the tube under pressure in use.

Claims

1. A tubular membrane module comprising:

a tubular shell having first and second cylindrical end portions and a permeate outlet adjacent one of said ends;

first and second cylindrical end fittings at the respective ends of the shell adapted to permit coupling of the module to external fluid inlet and outlet means for flow of said fluid through the module; and

,

a cylindrical membrane tube extending between said fittings within said shell and comprising a porous pipe with cylindrical ends having a permeable membrane cast on an inner surface thereof;

each said end fitting including;

(i) an inner end portion having a cylindrical tubular surface dimensioned to make surface-to-surface contact with a corresponding tubular surface portion at an end of the shell, said surfaces being adhesively sealed together;

(ii) an outer end portion having means to couple said module to said external fluid inlet means or outlet means; and

,

(iii) a cylindrical socket inwardly of said tubular surface of the inner end portion, said socket having a blind end closely receiving an end portion of the membrane tube, and in which the tube end portion is secured by adhesive, and a port of smaller diameter than and coaxially within said blind end providing communication between the interior of the tube and the exterior of the fitting through said outer end portion thereof,

whereby said module is formed as a monolithic structure.

2. A module as claimed in claim 1, wherein said tubular shell is a standard length of cylindrical plastic pipe.

3. A module as claimed in claim 2, wherein said plastic material is PVC, and which said end fittings are moulded in PVC and the end fittings and shell are secured together by epoxy resin adhesive.

4. A module as claimed in claim 3, wherein said membrane tube comprises a porous polyester pipe having a permeable membrane cast on its inner surface.

5. A module as claimed in claim 1, wherein said tubular shell is cylindrical in shape and wherein said tubular surface of each end fitting is a cylindrical interior surface of the fitting end portion and the corresponding tubular surface portion at the end of the shell is an external surface portion, and wherein the fitting is provided with an internal shoulder for defining a fully inserted position of the shell within the fitting.

6. A module as claimed in claim 1, wherein each said end fitting includes an external collar encircling the fitting between said inner and outer end portions.

7. A module as claimed in claim 1, wherein said outer end portion of each said fitting is of cylindrical shape and is provided with an external screw thread for coupling to said external fluid inlet means or outlet means.

8. A tubular membrane module comprising:

a tubular shell having first and second end portions and a permeate outlet adjacent one of said ends;

first and second end fittings at the respective ends of the shell adapted to permit coupling of the module to external fluid inlet and outlet means for flow of said fluid through the module; and

,

a cylindrical membrane tube extending between said fittings within said shell and comprising a porous pipe having a permeable membrane on an inner surface thereof;

each said end fitting including;

(i) an inner end portion having a tubular surface dimensioned to make surface-to-surface contact with a corresponding tubular surface portion at an end of the shell, said surfaces being sealed together;

(ii) an outer end portion having means for coupling to said external fluid inlet means or outlet means;

(iii) a socket inwardly of said tubular surface of the inner end portion, said socket having a blind end closely receiving an end portion of the membrane tube, and in which the tube end portion is secured by adhesive, and a port of smaller diameter than and within said blind end providing communication between the interior of the tube and the exterior of the fitting through said outer end portion thereof; and

,

(iv) means defining at least one permeate channel between the membrane tube and the shell, for assuring permeate flow to said permeate outlet when the module is in use.

9. A module as claimed in claim 8, wherein said means defining at least one permeate channel comprises mechanical spacer means formed on one of the exterior of the membrane tube and interior of the shell, said mechanical spacer means being at least substantially incompressible under internal pressures generated within the membrane tube when the module is in use.

10. A module as claimed in claim 9, wherein said mechanical spacer means is provided by a covering on the external surface of the membrane tube, the covering being formed by a material which provides said mechanical spacing while permitting permeate flow through the material to the permeate outlet.

11. A module as claimed in claim 10, wherein said covering comprises a woven material applied to the exterior of the membrane tube.

12. A module as claimed in claim 11, wherein said covering comprises a sock of said woven material that substantially encloses the membrane tube between said end fittings.

13. A module as claimed in claim 11, wherein said woven material is braided in place on the membrane tube.

14. A module as claimed in claim 11, wherein said woven material takes the form of a tape spirally wound around the membrane tube.

15. A module as claimed in claim 9, wherein the interior surface of the shell is provided with an array of longitudinally extending grooves and intervening lands which are distributed around the circumference of the shell and provide said flow channels and mechanical spacer means respectively, and wherein the shell further includes at least one circumferential flow channel providing communication between said longitudinally extending grooves and said permeate outlet.

16. A module as claimed in claim 10, wherein said covering comprises a porous tape spirally wound around the membrane tube.