DIALYZING MEMBRANE ENVELOPE

• US 3,627,137 A
• Filed: 10/10/1968
• Issued: 12/14/1971
• Est. Priority Date: 10/10/1968
• Status: Expired due to Term

• Current Assignee: Milan Bier
• Original Assignee: Milan Bier
• Inventors: Bier, Milan
• Primary Examiner(s): Spear, Jr., Frank A.
• Application Number:
  US04/766,592
• Time in Patent Office: 1,160 Days
• Field of Search: 210/22,321
• US Class Current: 210/321.75
• CPC Class Codes: B01D 61/28 Apparatus therefor
• CPC Class Codes: B01D 63/08 Flat membrane modules

Abstract

A parallel flow dialyzer suitable for use as an artificial kidney utilizes a dialyzing membrane envelope spread within and sealed to an outer frame. This membrane envelope may comprise plastic netting which provides the necessary support for the membranes and channels for the flow of dialyzate, while at the same time causes some mixing of blood, thus improving on the performance of the dialyzer. It also permits greatly simplified design of outer boards containing said envelope. The envelope is manufactured mainly through the use of double-coated pressuresensitive adhesive tape.

Claims

1. A dialyzing membrane envelope for use in parallel flow dialyzers wherein said membranes constituting the two sides of the membrane envelope are spread within and adhesively sealed to a peripheral frame, said frame carrying attached to it liquid inlet and outlet ports, and said frame conveying to the membrane greater rigidity, said frame being made of closed cell foamed plastic or rubbery material, such as foamed polyurethane, foamed polyethylene, foamed rubber, or foamed polystyrene.

2. A dialyzing membrane envelope as claimed in claim 1, wherein said adhesive seal comprises double-coated pressure-sensitive adhesive tape.

3. A dialyzing membrane envelope claimed in claim 1, pretested for leakage and presterilized for use in artificial kidneys.

4. A dialyzing membrane envelope as claimed in claim 1, wherein plastic netting covers the major part of both outer surfaces of said membrane envelope, and iS spread within and sealed to said peripheral frame, said plastic netting protecting said membrane from rupture by underlying sharp edges of the grooved parallel dialyzer boards.

5. A dialyzing membrane envelope as claimed in claim 4, wherein sections of said membrane envelope adjacent to said inlet and outlet liquid ports are left unprotected by said plastic netting, said unprotected sections providing regions of increased depth of liquid layer within said membrane envelope serving to equalize the flow distribution of liquid contained in said membrane envelope along the width of said membrane envelope.

6. A dialyzing membrane envelope as claimed in claim 4, wherein said plastic netting has one set of parallel strands running in the direction of liquid flow within said membrane envelope, said parallel strands forming channels for the flow of dialyzate along the outer surface of said membrane envelope, whereas the transversal set of strands of said plastic netting lies across the direction of liquid flow in said membrane envelope, this set of strands causing mixing of said liquid flowing in said membrane envelope, and preventing the laminar flow of said flowing liquid.

7. A dialyzing membrane envelope as claimed in claim 4, wherein said plastic netting is of low density polyethylene or other similar flexible material.

8. A dialyzing membrane envelope as claimed in claim 4 wherein said plastic netting has from 5 to 50 strands per linear inch, the diameter of said strands being in the range of 0.010 inch to 0.100 inch.

9. A dialyzing membrane envelope as claimed in claim 4, wherein said membranes and plastic netting are adhesively joined to each other by partial compressions, the highly compressible peripheral frame being forced under pressure into the openings of said plastic netting, in a pattern complementary to that of the netting.

10. A dialyzing membrane envelope as claimed in claim 4, wherein said adhesive seal comprises double coated pressure sensitive adhesive tape.

11. A dialyzing envelope as claimed in claim 4, and means to contain said dialyzing envelope, said means providing two essentially flat and rigid surfaces, preventing the ballooning of the membrane envelope, said means having depressions for the seating of liquid inlet and outlet ports, and ports and manifolds for the inlet and outlet and distribution of dialyzate flow.

12. A dialyzing membrane envelope for use in parallel flow dialyzers, wherein said membranes constituting the two sides of the membrane envelope are adhesively sealed to a peripheral frame, said frame carrying attached to it liquid inlet and outlet ports, wherein plastic netting covers the major part of both outer surfaces of said membrane envelope, said plastic netting protecting said membranes from rupture by underlying sharp edges of the grooved parallel dialyzer boards.

13. A dialyzing membrane envelope as claimed in claim 12, wherein said plastic netting is adhesively sealed to said peripheral frame.

14. A parallel flow dialyzing apparatus comprising two or more elongated rigid generally flat boards clamped in face-to-face relationship, dialyzing membrane means sandwiched therebetween, membrane supporting elongated pieces of open mesh plastic netting interposed between said flat boards and said dialyzing membrane means, peripheral gasketing frame means of closed cell foamed plastic or rubbery material, such as foamed polyurethane, foamed polyethylene, foamed rubber, or foamed polystyrene, said gasketing frame means being sandwiched between said clamped boards and defining closed chambers between said boards, said closed chambers containing said dialyzing membrane means and said membrane supporting plastic netting, said apparatus being provided with inlet and outlet means at the opposite ends to admit two separate liquid flows, the first said liquid flow being contained within the interior of said dialyzing membrane means, the second said liquid flow being directed to thE exterior of said dialyzing membrane means, said membrane supporting open mesh plastic netting providing the channeling for the passageway of said second liquid flow between said inlet means at the opposite ends of the apparatus through the space defined by the exterior surfaces of said dialyzing membrane means, the interior surfaces of said flat rigid boards and said peripheral gasketing frame means.

15. A parallel flow dialyzing apparatus as claimed in claim 14, wherein said rigid generally flat boards have depressions for the seating of inlet and outlet ports for the first said liquid flow.

16. A parallel flow dialyzing apparatus as claimed in claim 14, wherein said dialyzing membrane means are constituted by a dialyzing membrane envelope for use in parallel flow dialyzers wherein said membranes constituting the two sides of the membrane envelope are spread within and adhesively sealed to a peripheral frame, said frame carrying attached to it liquid inlet and outlet ports, and said frame conveying to the membrane greater rigidity, said frame being made of closed cell foamed plastic or rubbery material, such as foamed polyurethane, foamed polyethylene foamed rubber, or foamed polystyrene.

17. A parallel flow dialyzing apparatus as claimed in claim 14, wherein said dialyzing membrane means are constituted by paired sheets of flexible dialyzing membrane materials having a contour to overlap said peripheral gasketing frame means when sandwiched between said boards for sealing engagement with said gasketing frame means.

18. A parallel flow dialyzing apparatus as claimed in claim 14, wherein said dialyzing membrane means are constituted by one or more cylindrical tubings formed by dialyzing membrane materials, kept in flat form by said rigid boards and said membrane supporting plastic netting.

19. A parallel flow dialyzing apparatus as claimed in claim 14, wherein said membrane supporting plastic netting has one set of parallel strands running in the direction of liquid flow within said dialyzing apparatus, said parallel strands forming channels for the flow of said second liquid between said inlet and outlet means at the opposite ends of the apparatus through the space defined by the exterior surfaces of said dialyzing membrane means, the interior surfaces of said flat rigid boards and said peripheral gasketing frame material, whereas the second transversal set of strands of said plastic netting lies across the direction of liquid flow in said dialyzing apparatus, this set of strands causing mixing of said first flowing liquid contained in said dialyzing membrane means, and preventing the laminar flow of said flowing liquid, said two sets of parallel plastic strands not lying in the same plane, but lying in two adjacent planes touching each other only in the crossover points between the two sets of strands.

20. A parallel flow dialyzing apparatus as claimed in claim 19, wherein set first set of parallel strands forming channels for the flow of said second liquid are oriented to lie against said flat rigid boards, said second set of transversal strands being oriented to lie against said dialyzing membrane means.

21. A parallel flow dialyzing apparatus as claimed in claim 14, wherein said membrane supporting plastic netting has from 5 to 50 strands per linear inch, the diameter of said strands being in the range of 0.010 inch to 0.100 inch.