GB1602793A - Mass transfer apparatus and method of manufacture thereof - Google Patents
Mass transfer apparatus and method of manufacture thereof Download PDFInfo
- Publication number
- GB1602793A GB1602793A GB10684/78A GB1068478A GB1602793A GB 1602793 A GB1602793 A GB 1602793A GB 10684/78 A GB10684/78 A GB 10684/78A GB 1068478 A GB1068478 A GB 1068478A GB 1602793 A GB1602793 A GB 1602793A
- Authority
- GB
- United Kingdom
- Prior art keywords
- plates
- stack
- membrane
- connector elements
- rigid
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 13
- 238000000034 method Methods 0.000 title claims description 11
- 239000012528 membrane Substances 0.000 claims abstract description 77
- 239000012530 fluid Substances 0.000 claims description 31
- 239000008280 blood Substances 0.000 claims description 20
- 210000004369 blood Anatomy 0.000 claims description 20
- 239000000463 material Substances 0.000 claims description 9
- 125000006850 spacer group Chemical group 0.000 claims description 7
- 238000010276 construction Methods 0.000 claims description 5
- 238000007789 sealing Methods 0.000 claims description 5
- 238000005219 brazing Methods 0.000 claims description 4
- 238000005266 casting Methods 0.000 claims description 4
- 229920003023 plastic Polymers 0.000 claims description 4
- 239000004033 plastic Substances 0.000 claims description 4
- 238000004382 potting Methods 0.000 claims description 4
- 229920005989 resin Polymers 0.000 claims description 4
- 239000011347 resin Substances 0.000 claims description 4
- 238000005476 soldering Methods 0.000 claims description 4
- 238000003466 welding Methods 0.000 claims description 4
- 210000004072 lung Anatomy 0.000 claims description 2
- 238000002844 melting Methods 0.000 claims description 2
- 230000008018 melting Effects 0.000 claims description 2
- 230000002093 peripheral effect Effects 0.000 claims description 2
- 210000004379 membrane Anatomy 0.000 description 53
- 238000009827 uniform distribution Methods 0.000 description 2
- 239000004593 Epoxy Substances 0.000 description 1
- 239000000853 adhesive Substances 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 230000000712 assembly Effects 0.000 description 1
- 238000000429 assembly Methods 0.000 description 1
- 230000001112 coagulating effect Effects 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 238000001631 haemodialysis Methods 0.000 description 1
- 230000000322 hemodialysis Effects 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 229920003229 poly(methyl methacrylate) Polymers 0.000 description 1
- 229920002239 polyacrylonitrile Polymers 0.000 description 1
- 239000004926 polymethyl methacrylate Substances 0.000 description 1
- 229920000098 polyolefin Polymers 0.000 description 1
- 229920005749 polyurethane resin Polymers 0.000 description 1
- 238000000108 ultra-filtration Methods 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D63/00—Apparatus in general for separation processes using semi-permeable membranes
- B01D63/14—Pleat-type membrane modules
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Separation Using Semi-Permeable Membranes (AREA)
- External Artificial Organs (AREA)
- Folding Of Thin Sheet-Like Materials, Special Discharging Devices, And Others (AREA)
Abstract
In the apparatus the stack of accordion folds (10), in each of which a support member (11) is placed on only one side of the membrane, is placed between two parallel rigid plates (12, 13) attached rigidly to one another while a determined load, uniformly distributed by virtue of two platens (14, 15) of a press, is maintained on the stack. Three connecting rods (17, 18, 19) are attached between the plates (12, 13) which are connected internally to all the folds. Apparatuses of uniform performance despite the possible irregularities of thickness of the membrane or of the support members are thus obtained in series. Application to the manufacture of haemodialysers. <IMAGE>
Description
(54) MASS TRANSFER APPARATUS AND METHOD OF
MANUFACTURE THEREOF
(71) We, AMERICAN HOSPITAL SUP
PLY CORPORATION, a U.S. Body Corporate, organized according to the laws of the State of Illinois, United States of America, of 1740 Ridge Avenue, Evanston, Illinois 60204, United States of America, do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it iS to be performed, to be particularly described in and by the follow instate ment:- The present invention relates to a mass transfer apparatus for the flow fluids separated by a stack made up of membrane and membrane support members and to a method of manufacturing such an apparatus.
The invention more particularly relates to an apparatus comprising a semipermeable membrane folded to form a stack of accordion pleats, disposed inside of a housing, and provided with the necessary ports for the introduction and evacuation of blood, dialysate and/or ultrafiltrate, the pleats of the stack on one side of the membrane containing a plurality of porous or open-mesh support members.
An apparatus of this general type is known, as disclosed in U.S. Patent 3,788,482. Generally the stack of the membrane in accordion pleats and of the support members is enclosed in a fluid-tight manner inside a housing. This housing may be either a box consisting of essentially two or more pieces suitably joined together for example, or an envelope made out of a suitable plastics material and moulded about said stack.
These boxes, being made according to a given model, all have exactly the same dimensions and, in addition, the mould being the same for all these envelopes, their external dimensions are all identical. Also it has been thought advantageous to have identical apparatuses in which the stacks in particular are of exactly the same height.
However, it has now been found that in actual practice the thickness of the membrane, and particularly of the support members, may vary slightly from one apparatus to another and that such slight variations, when multiplied by the number of pleats or number of support elements in a stack, may result in appreciable variations in the thickness of the blood films formed in different apparatuses of the same stack height and same external dimensions. Consequently, the performance and efficiency of these apparatuses may vary at random from one apparatus to another in an undesirable manner, presenting potentially serious problems in a field where reliability and uniformity of operation are deemed essential.
A solution to this problem can be achieved by an apparatus embodying the present invention which can be so constructed as to have reproducible performance characteristics so that the performance from one such apparatus to another will be substantially identical. The disadvantages associated with the abovementioned problems can thus be eliminated or at least greatly minimized.
Apparatus embodying the present invention can be of a simple and economical construction which allows an easy flow of blood under a small pressure drop and with uniform distribution of blood over the entire membrane, and within successive pleats of the same membrane, and which requires only a limited volume of blood within the body of the apparatus.
In accordance with the present invention there is provided a mass transfer apparatus comprising two rigid and essentially rectangular plates, a stack made up of membrane and membrane support members disposed between said plates and subjected to a compressive load of predetermined value by said plates, and at least two connector elements, each respective connector element being bonded to a pair of edges of respective said plates, each edge of said pair facing away from the stack in essentially the same direction as one another to connect the plates to one another and thereby maintain said compressive load of predetermined value on said stack. Before the connector elements are bonded to the stack, the stack may be subjected to a uniformly distributed said compressive load of predetermined value, the connector elements then being bonded to the plates so as to maintain the stack under the uniformly-distributed load.
In a preferred apparatus embodying the invention, the said two plates each have flat parallel surfaces, the respective internal surface of each plate being parallel to one another and maintained in said parallel position by the connector elements; the said membrane is folded to form said stack of closely spaced accordion pleats covering substantially the whole of said internal surfaces of said plates; at least one of said support members is disposed within each pleat on one side only of said membrane; and the mass transfer apparatus additionally includes at least three ports for the flow of fluid, a housing enclosing said membrane stack, said plates, and said ports, and means for embedding imperviouslv the edges of the membrane over the whole length of the membrane.
According to another aspect of the invention there is provided a method for manufacturing a mass transfer apparatus comprising the steps of making up a stack of membrane and support members, locating the stack between two rigid and essentially rectangular plates, exertmg a compressive load of predetermined value on said plates whereby said load is exerted on said stack, and bonding at least two connector elements each respectively to a pair of edges of respective said plates, each edge of said pair facing away from the stack in essentially the same direction as one another to connect the plates to one another and thereby maintain a compressive load on said stack.
A preferred method of manufacturing such a mass transfer apparatus comprises the following steps:
(a) Making up an assembly by folding a semipermeab e membrane in accordion-like manner into a stack of closely spaced pleats around support members disposed within the pleats on one side of said membrane, and placing the accordion-folded stack containing said support members between a pair of rigid plates each having flat, parallel surfaces;
(b) Applying a predetermined and uniformly-distributed compressive load on said assembly while maintaining said plates in parallel relationship;
(c) Bonding each connector element to a respective pair of edges of said plates to connect the plates to one another and thereby maintain a compressive load on said stack; and
(d) Providing at least three ports for the flow of fluid and a housing enclosing said membrane stack, said plates and said ports and embedding imperviously the edges of the membrane over the whole length of the membrane.
The uniformly distributed predetermined compressive load may be conveniently applied by introducing the assembly between the two platens of a press, at least one of which is movable with respect to the other, their opposite faces remaining constantly parallel during all positions of the platens and applying the said load on the assembly by means of the press.
The connector elements, which are preferably in the form of rigid headers which additionally provide respective flow ports, are conveniently bonded to the respective edges of the plates by sticking, sealing, melting, welding, soldering, brazing, potting or casting, while the assembly is maintained under the constant load.
The housing of the assembly (the plates thereof having been rigidly secured by the connector elements) may be formed in any desired manner in accordance with procedures which are themselves known.
A still better understanding of the features of the present invention and its inherent advantages will become apparent from the following description of a preferred embodiment thereof with reference to the accompanying drawing in which the sole figure is a perspective view of a hemodialyzer disposed during its construction between the two platens of a press.
Referring now to the drawing, it will be seen that the semipermeable membrane 10 is folded in accordion pleats around support members 11 which are disposed only on one side of the membrane. Membrane pleats cover the whole surface of a lower rigid plate 12 which is preferably made of polymethylmethacrylate or other rigid plastics material and whose shape is generally rectangular.
An upper rigid plate 13, generally identical with the lower rigid plate 12, covers the whole surface of the top pleat of the membrane. Each plate is rigid and has flat, parallel upper and lower surfaces. The upper and the lower ends of the membrane may be sealed in a leakproof manner by any desired per se known means respectively to the upper and lower platens, for instance, by means of epoxy, polyurethane resin or other suitable adhesive agent.
Plates 12 and 13 are disposed between the platens 14 and 15 of the press. The opposite faces of the platens 14 and 15 are exactly parallel and must remain parallel when moving one with respect to the other.
For example, the platen 14 is fixed while the platen 15 is movable, being attached to the piston 16 of a press. The other elements of the press, being conventional and not critical for an understanding of the preset; invention, are not shown.
The support members used in this apparatus within the pleats of the mem brane may be of various types per se well known in the art for maintaining a suitable spacing between adjacent folds and yet providing a minimum impediment to flow of dialysate. Each takes the form of a spacer comprising a plastic non-woven mesh (e.g., of polyolefin) which has two layers of threads disposed at substantially right angles to each other and then heat sealed, each layer originally being in a different plane. A support member may generally comprise one or two spacers between pleats of the membrane. The membrane may be any flexible and semipermeable membrane of various types as well known in the art, for example known membranes suitable for hemodialysis and treatment of blood by ultrafiltration such as Cuprophan (a Registered Trade Mark for a commercially available cellulosic material) or polyacrylonitrile.
The stack of membrane and support members constitutes a compressible and elastic assemblage whose height may vary depending on the compressive force applied. Furthermore, when the same load or compressive force is applied to different stacks formed of membrane and spacer materials taken from the same sources, stack height variations of from 0.5% to 10% may occur, such variations commonly falling in the range of 2% to 6%. Such variations arise because of minute irregularities or differences in the thickness of materials used for the support elements and membranes of the dialyzers, and because such differences may be magnified by the multiplicity of pleats and support elements required in each apparatus.
We find that an apparatus embodying the invention providing greater reproducibility and, in general, better results, may be obtained if, although always employing the same conventional elements such as membrane, support members and plates, the stacks of these elements are produced under a uniform predetermined load without regard to whether the final height of one stack differs from another stack having the same number of pleats and spacers. It is to be understood that one may employ either a constant pressure, or a weight or any other suitable means which results in a uniform load distributed evenly over and throughout the stack of membrane and support members by reason of the rigid plates.
This uniform load of a predetermined value may be readily established for an assemblage of any given size and number of pleats, using any given membrane and spacer materials, by a series of simple tests.
If the loading is too high, the pressure drop of fluids when traversing the apparatus may be too high and the liquid films may be locally too thin and/or the flow of fluids may be at rates that are too slow, thus adversely affecting the operation and efficiency of the apparatus. In the case of blood, there even may be the risk of coagulating the blood because of the reduced flow. If, on the contrary, the uniform load is too low, the channels offered for fluid flow may be too large and the distribution of fluid inside the apparatus may become preferential as between the different pleats feeding in parallel from a common header, and the rate of circulation locally may become too slow, leading to the same drawbacks mentioned above. At optimum loading, the cross sectional dimensions of the fluid layers within the membrane pleats and the rates of fluid flow therein will provide the best exchange or transfer characteristics for the materials and construction used. Once an optimum compressive loading value has been established to achieve the desired operating characteristics for an apparatus of given size and materials, repeated use of that same loading in the fabrication of similar units will result in apparatuses having essentially the same operating characteristics.
Moreover, such reproducibility of operating characteristics will be obtainable even though the stack height of one assembly may differ from that of the next because of virtually indetectable variations in the thickness of the multiple support members, and sometimes even of the membranes, used in successive assemblies.
In a method embodying the present invention illustrated with reference to the drawing, the uniform compressive load is applied to rigid plates which have flat, parallel faces and which remain constantly parallel to each other, the stack of membrane pleats and spacer elements being disposed therebetween. It has been found that this disposition promotes the uniform distribution of fluids within the pleats of the membrane when the apparatus so formed is put to use. Thus, rigid plates 12 and 13 are maintained parallel to each other under a uniform pre-established loading, and without regard to differences in the spacing of such plates from one apparatus to another, and are thereafter fixed to each other by connector elements bonded to the opposite laterally facing longitudinal edges of the upper and lower plates. Advantageously, a plurality of rigid connector elements are provided, which extend vertically and are bonded to the laterally facing edges of the plates adjacent the corners thereof.
The connector elements may take the form of, for example, bars, rods, sheets or plates, which extend from one plate to the other adjacent the creases of the membrane.
Such elements may be stuck, sealed, melted, welded, soldered, brazed, potted or cast, to form rigid links between the side edges of the two plates. If desired, they may be integral with one or the other of the two plates.
In the particularly preferred apparatus embodying the invention and illustrated in the drawing fluid-conducting headers 17, 18, 19 provide the rigid connector elements between the lower plate and the upper plate. Each header has an inwardly-facing vertical channel which communicates with all the pleats of the stack on the side of the membrane facing that header and is otherwise closed except for a port advantageously provided with a short pipe 20, 21, 22 to which a suitable tube may be connected in a fluid-tight manner. Such headers are bonded to the side edges of the lower and the upper plates, for example at the points 23, 24, 25, 26, while the assemblage is maintained under a predetermined, uniform, and constant load. Since the headers are bonded to the plates, rather than being mechanically latched to such plates, the step of securing the headers may be easily achieved without imposing any forces on the plates which might alter their spacing or which might permit any significant changes in such spacing after the bonding action is completed and the assembled structure is removed from the press.
The desired construction of the apparatus is then achieved by bringing about the peripheral fluid-tightness by means known per se to the art. For instance, it is possible to introduce the assemblage (with the headers) into a mould and to cast in the mould a fluid resin for enclosing that assemblage. It is also possible to employ a box (equipped with port openings for receiving tubes or pipes 20, 21, 22), for example in two pieces, and to cast a fluid resin around the assemblage inside the assembled box. Thus the edges of the membranes may be sealed over their whole length.
The apparatus has been described in a form particularly adapted for use as a hemodialyzer provided with four ports, two for blood and two for dialysate, for treatment of blood. Alternatively, there may be provided one part only for the exit of ultrafiltrate. In each of these cases, the features described above improve the circulation of blood or other fluid and hence the efficiency of the apparatus.
This apparatus is also convenient for any other treatment of blood, for instance as a blood oxygenator in an artificial lung.
Moreover, blood and dialysate are merely examples of fluids for which the apparatus is suitable, and mass transfer may be efficiently achieved between other fluids. Also other types of membranes or folded sheets may be employed as dictated by the particular fluids and by the nature of the desired transfer between the fluids.
It is to be particularly emphasized that one of the main advantages of the present invention is that is enables one to manufacture a series of like devices which, because of the application of the same predetermined uniform load or force during manufacture of each of the devices of the series, will have essentially the same operating characteristics during use, despite minute differences in the thickness of the membranes and/or support members of each of the devicesof the series.
WHAT WE CLAIM IS:
1. A mass transfer apparatus comprising two rigid and essentially rectangular plates, a stack made up of membrane and membrane support members disposed between said plates and subjected to a compressive load of predetermined value by said plates, and at least two connector elements, each respective connector element being bonded to a pair of respective said plates, each edge of said pair facing away from the stack in essentially the same direction as one another to connect the plates to one another and thereby maintain said compressive load of predetermined value on said stack.
An An apparatus according to claim 1, wherein the said connector elements maintain said stack under a uniformly-distributed said compressive load of predetermined value.
3. A mass transfer apparatus according to claim 1 or claim 2, wherein the said two plates each have flat parallel surfaces, the respective internal surface of each plate being parallel to one another and maintained in said parallel position by the connector elements; the said membrane is folded to form said stack of closely spaced accordion pleats covering substantially the whole of said internal surfaces of said plates; at least one of said support members is disposed within each pleat on one side only of said membrane; and the mass transfer apparatus additionally includes at least three ports for the flow of fluids, a housing enclosing said membrane stack, said plates and said ports, and means for embedding imperviously the edges of the membrane over the whole length of the membrane.
4. An apparatus according to claim 1, claim 2 or claim 3, in which said connector elements bonded to said rigid plates comprise bars, rods, sheets and/or plates, and said connectors are bonded to said plates by sticking, sealing, welding, soldering, brazing, potting or casting.
5. An apparatus according to any one of claims 1 to 4, in which at least one of said connector elements is integral with one of the two rigid plates.
6. An apparatus according to any one I claims 1 to 5, in which the connector elements bonded to said rigid plates comprise fluid conducting headers.
**WARNING** end of DESC field may overlap start of CLMS **.
Claims (17)
1. A mass transfer apparatus comprising two rigid and essentially rectangular plates, a stack made up of membrane and membrane support members disposed between said plates and subjected to a compressive load of predetermined value by said plates, and at least two connector elements, each respective connector element being bonded to a pair of respective said plates, each edge of said pair facing away from the stack in essentially the same direction as one another to connect the plates to one another and thereby maintain said compressive load of predetermined value on said stack.
An An apparatus according to claim 1, wherein the said connector elements maintain said stack under a uniformly-distributed said compressive load of predetermined value.
3. A mass transfer apparatus according to claim 1 or claim 2, wherein the said two plates each have flat parallel surfaces, the respective internal surface of each plate being parallel to one another and maintained in said parallel position by the connector elements; the said membrane is folded to form said stack of closely spaced accordion pleats covering substantially the whole of said internal surfaces of said plates; at least one of said support members is disposed within each pleat on one side only of said membrane; and the mass transfer apparatus additionally includes at least three ports for the flow of fluids, a housing enclosing said membrane stack, said plates and said ports, and means for embedding imperviously the edges of the membrane over the whole length of the membrane.
4. An apparatus according to claim 1, claim 2 or claim 3, in which said connector elements bonded to said rigid plates comprise bars, rods, sheets and/or plates, and said connectors are bonded to said plates by sticking, sealing, welding, soldering, brazing, potting or casting.
5. An apparatus according to any one of claims 1 to 4, in which at least one of said connector elements is integral with one of the two rigid plates.
6. An apparatus according to any one I claims 1 to 5, in which the connector elements bonded to said rigid plates comprise fluid conducting headers.
7. An apparatus according to any one of
claims 1 to 6, in which two of said connector elements are bonded to the same said edges of said plates adjacent opposite longitudinal end regions of said plates.
8. An apparatus according to any one of the preceding claims, in which two pairs of said connector elements are provided, each pair being bonded to a respective said edge of each of said rigid rectangular plates, the four connector elements being respectively adjacent the four corners of the stack.
9. An apparatus according to any one of the preceding claims, in which each support member is planar and comprises at least one spacer formed of a non-woven mesh of plastics material which has two layers of threads heat sealed together, each layer being in a different plane prior to heat sealing.
10. A method of manufacturing a mass transfer apparatus comprising the steps of making up a stack of membrane and membrane support members, locating the stack between two rigid and essentially rectangular plates, exerting a compressive load of predetermined value on said plates whereby said load is exerted on said stack, bonding at least two connector elements each respectively to a pair of edges of respective said plates, each edge of a said pair facing away from the stack in essentially the same direction as one another to connect the plates to one another and thereby maintain a compressive load on said stack.
11. A method according to claim 10 comprising the steps of:
(a) Making up an assembly comprising a semipermeable said membrane folded in accordion-like manner into a number of closely spaced pleats around the said support members, which said support members are inserted into or between the pleats on one side only of said membrane, and locating the folded membrane and support members between two said rigid plates, which ngla plates are essentially nat and ot uniform thickness;
(b) Introducing said assembly between the two platens of a press, at least one of which is movable with respect to the other,
(c) Exerting a uniformly distributed said predetermined load on said assembly by means of said press;
(d) Conducting the said step of bonding the connector elements to the said edges of the plates of the assembly by sticking, sealing, melting, welding, soldering, brazing, potting or casting while said assembly is maintained under said uniformly-distributed and predetermined compressive load; and
(e) Enclosing the said stack so as to define a housing into which fluid can flow into or out of each of the opposite sides of the stack.
12. A method according to claim 11, in which opposing faces of the platens of the press remain constantly parallel during all positions of the platens.
13. A method of manufacturing a mass transfer apparatus as defined in claim 3 comprising:
(a) Making up an assembly by folding a semipermeable membrane in accordion-like manner into a stack of closely spaced pleats around support members disposed within the pleats on one side of said membrane, and placing the accordion-folded stack containing said support members between a pair of rigid plates each having flat, parallel surfaces;
(b) Applying a predetermined and uniformly-distributed compressive load on said assembly while maintaining said plates in parallel relationship;
(c) Bonding each connector element to a respective pair of edges of said plates to connect the plates to one another and thereby maintain a compressive load on said stack; and
(d) Providing at least three ports for the flow of fluid and a housing enclosing said membrane stack, said plates and said ports, and embedding imperviously the edges of the membrane over the whole length of the membrane.
14. A method according to claim 13, in which the rigid vertically extending connecting members are headers providing respective said ports for the flow of fluids into or out of the assembly on both sides of the membrane stack.
15. A method as claimed in claim 10 or claim 11, wherein the said predetermined compressive load is uniformly distributed on said assembly.
16. Apparatus according to claim 1 substantially as herein described with reference to and as illustrated in the accompanying drawings.
17. Method according to claim 10 substantially as herein described with reference to the accompanying drawings.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US77957577A | 1977-03-21 | 1977-03-21 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| GB1602793A true GB1602793A (en) | 1981-11-18 |
Family
ID=25116872
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB10684/78A Expired GB1602793A (en) | 1977-03-21 | 1978-03-17 | Mass transfer apparatus and method of manufacture thereof |
Country Status (11)
| Country | Link |
|---|---|
| JP (1) | JPS53127377A (en) |
| BE (1) | BE865095A (en) |
| CA (1) | CA1112580A (en) |
| CH (1) | CH627086A5 (en) |
| DE (1) | DE2812080A1 (en) |
| ES (2) | ES468067A1 (en) |
| FR (1) | FR2384524A1 (en) |
| GB (1) | GB1602793A (en) |
| IT (1) | IT1093246B (en) |
| NL (1) | NL7802931A (en) |
| SE (1) | SE7802904L (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2918140C2 (en) * | 1979-05-05 | 1985-02-07 | Fresenius AG, 6380 Bad Homburg | Dialyzer |
| AU526959B2 (en) * | 1980-07-23 | 1983-02-10 | Terumo Corp. | Blood filter with multi-mesh-core layers and residue outlet |
| JPS57177529U (en) * | 1981-05-06 | 1982-11-10 | ||
| FR2536297B1 (en) * | 1982-11-19 | 1989-01-27 | Fresenius Ag | PLATE DIALYZER |
| DE8236602U1 (en) * | 1982-12-28 | 1983-04-28 | Sartorius GmbH, 3400 Göttingen | FILTERS FOR WATER FILTRATION, ESPECIALLY FOR DE-PYROGENIZATION AND / OR STERILIZATION OF INFUSION SOLUTIONS |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR1597874A (en) * | 1968-12-16 | 1970-06-29 | ||
| US3757955A (en) * | 1971-08-09 | 1973-09-11 | Baxter Laboratories Inc | Multi-layer membrane type mass transfer device and process |
| US3780870A (en) * | 1972-02-22 | 1973-12-25 | W Esmond | Artificial body member |
| US3864265A (en) * | 1973-06-25 | 1975-02-04 | Galen Lab Inc | Edge sealed folded membrane |
| FR2270917B1 (en) * | 1974-05-16 | 1978-12-29 | Rhone Poulenc Ind |
-
1978
- 1978-03-10 CH CH264778A patent/CH627086A5/en not_active IP Right Cessation
- 1978-03-14 SE SE7802904A patent/SE7802904L/en unknown
- 1978-03-17 GB GB10684/78A patent/GB1602793A/en not_active Expired
- 1978-03-17 NL NL7802931A patent/NL7802931A/en not_active Application Discontinuation
- 1978-03-20 ES ES468067A patent/ES468067A1/en not_active Expired
- 1978-03-20 CA CA299,284A patent/CA1112580A/en not_active Expired
- 1978-03-20 IT IT21375/78A patent/IT1093246B/en active
- 1978-03-20 DE DE19782812080 patent/DE2812080A1/en not_active Withdrawn
- 1978-03-20 BE BE186099A patent/BE865095A/en not_active IP Right Cessation
- 1978-03-20 JP JP3115578A patent/JPS53127377A/en active Pending
- 1978-03-21 FR FR7808839A patent/FR2384524A1/en not_active Withdrawn
-
1979
- 1979-01-16 ES ES476892A patent/ES476892A1/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| IT7821375A0 (en) | 1978-03-20 |
| ES468067A1 (en) | 1979-09-01 |
| JPS53127377A (en) | 1978-11-07 |
| DE2812080A1 (en) | 1978-10-05 |
| FR2384524A1 (en) | 1978-10-20 |
| BE865095A (en) | 1978-09-20 |
| SE7802904L (en) | 1978-09-22 |
| CH627086A5 (en) | 1981-12-31 |
| NL7802931A (en) | 1978-09-25 |
| CA1112580A (en) | 1981-11-17 |
| IT1093246B (en) | 1985-07-19 |
| ES476892A1 (en) | 1979-10-16 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP0508645B1 (en) | Filters and filter units | |
| US4310416A (en) | Plate type fluid treatment apparatus | |
| CA1056314A (en) | Accordion fold flat plate dialyzer | |
| EP0566114B1 (en) | Outside perfusion type blood oxygenator | |
| US9038830B2 (en) | Filter device | |
| US3864265A (en) | Edge sealed folded membrane | |
| WO1990007943A1 (en) | Oxygenator wedge configuration | |
| US4016081A (en) | Staged membrane diffusion device and membrane support | |
| US4219422A (en) | Apparatus for mass transfer between fluids, provided with an interposed selectively permeable diaphragm unit | |
| US3976576A (en) | Dialyzer cartridge | |
| WO2002076529A1 (en) | Blood processing device | |
| US3831763A (en) | Separation apparatus | |
| US20020008063A1 (en) | High capacity gravity feed filter for filtering blood and blood products | |
| JPS5921641B2 (en) | plate type dialyzer | |
| US3464562A (en) | Dialyzing apparatus and method of making the same | |
| US4431539A (en) | Semipermeable membrane mass transfer apparatus and method for making same | |
| GB1602793A (en) | Mass transfer apparatus and method of manufacture thereof | |
| US3051316A (en) | Exchange apparatus | |
| US3862031A (en) | Multi-layer membrane type mass transfer device and process | |
| US4304669A (en) | Device for the mass transfer between fluids | |
| US3956449A (en) | Flat plate dialyzer and method of making same | |
| US4159250A (en) | Dialyzer casing | |
| CA1118367A (en) | Semipermeable membrane mass transfer apparatus having slotted support members | |
| JPS61240964A (en) | Body fluid treating device and its production | |
| US3485902A (en) | Method of making a dialyzing element |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PS | Patent sealed [section 19, patents act 1949] | ||
| PCNP | Patent ceased through non-payment of renewal fee |