IL44047A

IL44047A - Plate dialyzer

Info

Publication number: IL44047A
Application number: IL44047A
Authority: IL
Original assignee: Baxter Laboratories Inc
Priority date: 1973-02-08
Filing date: 1974-01-21
Publication date: 1976-12-31
Also published as: ES422892A1; SE7708439L; DK549278A; AU6517574A; CA1054069A; ZA74349B; JPS49112866A; NL7401373A; IL50656A0; BR7400922D0; DK549178A; FR2217046B1; BE810219A; DE2406077C2; GB1451701A; CA1032480A; FR2217046A1; CA1046426A; NL164748C; CA1053870A

Abstract

1451701 Dialysis apparatus BAXTER LABORATORIES INC 1 Feb 1974 [8 Feb 1973] 04679/74 Heading B1X A diffusion device such as a dialyser comprises a plurality 'of stacked plates separated by membranes so as to define a first set of flow paths between adjacent membranes and a second set of flow paths across the plates, each plate having a profiled membranesupporting surface provided with a plurality of rows of spaced projections which support a corresponding overlying membrane, each membrane being stretched in one direction over the projections, the centre-to-centre spacing of the projections in said one direction being greater than the centre-to-centre spacing of the projections in a direction transverse to said one direction. The stack may be bracketed between pressure plates and enclosed in a pair of hollow shells. The membranes may be of cellulose and the device may be used for haemodialysis or blood oxygenation. [GB1451701A]

Claims

1. In a diffusion device such as a dialyzer, a stack of plates separated by semi-permeable membranes to provide a pair of separate, isolated flow paths through said diffusion device on opposite sides of said membranes, said plate having a membrane-supporting, profiled surface comprising a plurality of rows of upstanding projections, in which said membranes are disposed across said plates over said projections while stretched in one direction, the spacing of the centers of the projections in rows in the general direction of stretching being greater than the center-to-eenter spacing of said projections in rows transverse to the general direction of stretching, to prevent undue saggin of said membrane upon wetting in said transverse direction, whi?e permitting low flow resistance across said plates, said surface also comprising a plurality of support ridges extending in continuous, uninterrupted fashion across said plate in the general direction of said flow paths, to abut corresponding support ridges on an adjacent plate of the stack, tooontrol the spacing between facing plates.

2. The diffusion device of Claim 1 in which the separate, isolated flow paths across the plates are generally parallel and countercurren . 1 or

3. 5. The diffusion device of Claim 2 in which the projections of alternate rows are laterally shifted with respect to the projections of adjacent rows to provide generally crossing fluid flow channels across said plates. 44047/3

4. The diffusion device of any one of Claims 1 to 3 in which said spacing of the projections in rows in 3aid general direction of stretching is at least two times greater than the spacing of the projections in rows transverse to said general direction of stretching, and said general direction of stretching is in longitudinal relation to the general direction of the fluid flow channels.

5. The diffusion device of any of the preceding Claims in which said membrane is no more than 20 microns thick, and said projections are spaced from 0.3 to 1.5 mm. apart in rows transverse to said general direction of stretching.

6. The diffusion device of any of the preceding Claims in which said stack of plates is bracketed by a pair of relatively thick pressure plates to uniformly distribute compressive pressure placed on said stack.

7. The diffusion device of any of the preceding Claims in which said stacked plates are enclosed in a pair of hollow shells which cooperate to enclose said stacked plates, said shells each defining peripheral flanges which abut one another, and a frame nember formed about exterior portions of said flanges for holding the flanges in firm, abutting relation. 44047/3

8. The diffusion device of Claim 7 in which said hollow shells each define a central fluid port having a peripheralwall, and a manifold chamber having peripheral edges constituting means for conducting fluid across said plates, said manifold chamber having a tapered depth, in which said depth of said manifold chamber at essentially all points along radial lines extending from said peripheral wall to meet said peripheral edges in perpendicular relation thereto is essentially equal to the following expression: + C, in which dQ is the depth of the manifold 2S x (1-S2/S02) chamber directly underneath the peripheral wall multiplied by the circumference of said central fluid port, S is the distance of the point measured along a said radial line measured from the peripheral wall of said fluid port, SQ is the total distance from the peripheral wall of said fluid port along said radial line to the peripheral edge of said manifold, and C is the minimum depth of said chamber at said peripheral edge.

9. The diffusion device of any of the preceding Claims in which said plates have front sides and sealing shoulders on opposed side edges, said rows of upstanding projections being defined on said plate between the shoulders, the front side of each plate being covered by a said membrane folded at opposed ends about the edges of said plate between the sealing shoulders, so that opposed membrane ends lie adjacent to rear side of said plate, the plates being arranged in face-to-face and back-to-back relation respectively with adjacent plates to clamp said membrane ends between rear sides of adjacent plates and to clamp membrane edges between said sealing shoulders, first 44047/2 manifold means for conducting a fluid across said plates through said fluid flow channel between the plate and its associated membrane, and second manifold means for conducting fluid across said plates between the membranes of plates lying in face-to-face relation. 9

10. The diffusion device of Claim 7 ia which add plates define near each edge between said sealing shoulders a plurality of grooves extending transversely to the direction of said fluid flow channels and communicating therewith, said grooves being of differing lengths and communicating at one end through said sealing shoulders to the edge of said plate, to provide uniformly distributed fluid to the space between each plate and its associated membrane, and to correspondingly collect said fluid and convey it through a sealing shoulder to the exterior.

11. In a diffusion device such as a dialyzer comprising a plurality of stacked plates and overlying membranes, said plates defining a plurality of rows of spaced projections of uniform height for forming flow channels, in which said membranes overlying safi plates are selectively tensioned in one direction with respect to other directions over said projections, the center-to-center spacing of said projections in said one direction being greater than the center-to-center spacing of said projections in a direction transverse to said on^djaection.

12. The diffusion device cf Claim 11 in which the general path of fluid flow across membranes of plates approximates said one direction. 44047/3

13. The diffusion device of Claim 11 or 12 in which said projections are spaced in rows in said one direction at least two times fairther apart than in said transverse direction.

14. The diffusion device of any of Claim 11 to 13, in which said membrane is made of a cellulosic material.

15. The diffusion device of any of Claims 11 to 14 in which each plate has a front side with sealing shoulders on opposed side edges, said rows of projections being defined between the sealing shoulders, the front side of each plate being covered by a said membrane folded at opposed ends about the edges of said plate between the sealing shoulders, so that opposed membrane ends lie adjacent to the rear side of said plate, the plates being arranged in face-to-face and back-to-back relation respectively with adjacent plates to clamp said membranes between the rear sides of adjacent plates and to clamp membrane edges between said sealing shoulders, first manifold means for conducting a fluid across said plates through said fluid flow channels between the plate and its associated membrane, and second manifold means for conducting fluid across said plates between the membranes of plates lying in face-to-face relation.

16. In a diffusion device such as a dialyzer comprising a plurality of stacked plates and overlying membranes , in which one face of the plates defines a profiled surface to define flow channels thereacross, a line of spaced, projecting teeth defined on one edge of said plates to define flow channels communicating across said plate edge between the plate surface and the exterior adjacent said 44047/3 overlaid and surrounded by a membrane, whereby blood passing between said teeth across each plate is separated from said plate by its associated membrane.

17. The diffusion device of Claim 16 in which said plates are so stacked that the line of spaced, projecting teeth of adjacent, facing plates are located on opposite sides of said adjacent plates. For the Applicants