SINGLE WELDING CONTACT

Description

FIELD

[0001] In accordance with at least selected embodiments, the present disclosure is directed to novel or improved membrane contactors.BACKGROUND

[0002] Membrane contactors are devices used to, among other things, degas liquids. For example, membrane contactors may be used to degas the ink used in, for example, industrial printers.

[0003] Hollow fiber membrane contactors typically operate on a diffusion principle. Such membrane contactors typically have a shell side and a lumen (or tube) side, and these sides are separated with a membrane, for example, a microporous membrane. In operation, the gas entrained liquid is introduced into one side of the contactor, while vacuum or a combination of vacuum and swept gas is passed through the other side. As the liquid passes through its side, the gas diffuses across the membrane into the other side.

[0004] Two small membrane contactors are illustrated in Figures 1 and 2 (both prior art). Such Liqui-Cel ®< brand contactors are commercially available from the Membrana-Charlotte Division of Celgard, LLC of Charlotte, NC. While these are excellent small membrane contactors, there is still a need for improved small membrane contactors or improved production methods for such contactors for at least certain applications.

[0005] US 2007 / 278145 A1 describes a membrane contactor that includes a housing, a stack of membrane mats, and a cap. The housing has a closed end and an open end. The closed end includes an outlet port. The cap is united to the open end and includes an inlet port.

[0006] US 7 638 049 B2 discloses a hollow fiber membrane contactor. The hollow fiber membrane contactor includes a cartridge, a shell, a first end cap, and a second end cap. The shell, which is adapted for enclosing the cartridge, has two ends and an opening. The cartridge further includes a perforated center tube, a hollow fiber fabric, a first tube sheet, a second tube sheet, and a plug. The first end cap has an opening therethrough, which is in communication with hollow fiber lumens via said first headspace. The second end cap has an opening, and it is in communication with the center tube.

[0007] US 5 059 374 A discloses a process for sealing a hollow fiber membrane separation module into a case. The hollow fiber membrane separation module is formed from a plurality of hollow fibers arranged in a bundle surrounding a core and having tube sheets surrounding each end of the bundles which bind the hollow fibers together. The disclosed process simultaneous with such sealing creates first and second spaces overlying the ends of the plurality of hollow fibers.

[0008] WO 2006 / 081059 A2 describes a hollow fiber cartridge including a stack of hollow fiber mats. The stack has a major axis and two end faces Each mat is substantially perpendicular to the axis. An end cap is united to each end face.

[0009] US 2005 / 194305 A1 discloses a hollow fiber membrane contactor, and method of making same. The hollow fiber membrane contactor includes a shell having an internal bonding surface, an interlocking geometry ring being provided on said internal bonding surface; a unitized structure; a potting material joining said unitized structure to said shell at said interlocking geometry ring thereby forming an interlocking seal therebetween; and end caps. The end caps are adjoined to lateral ends of said shell.

[0010] US 2001 / 035093 A1 describes a gas-permeable membrane apparatus which comprises a chamber having an inlet-end connector portion and an outlet-end connector portion; a tube bundle housed within said chamber; a cylindrical coupling insertable into each of the connector portions of said chamber, having at a first end thereof a line connector portion for connecting a liquid inlet line or outlet line and having at a second end thereof a tube bundle connector portion for connecting said tube bundle; and a fastener member for threadably fastening each of said cylindrical couplings.

[0011] US 2006 / 081524 A1 describes a hollow fiber membrane contactor which includes a perforated center tube, a first mat comprising a first hollow fiber membrane, a second mat comprising a second hollow fiber membrane, a first tube sheet, a second tube sheet, a shell, and end caps. The shell surrounds the first and second mats, and it is sealed to the tube sheets. The end caps are affixed to the shell thereby defining headspaces between the tube sheets and the end caps.SUMMARY OF THE INVENTION

[0012] The present invention concerns a membrane contactor and a method of making the membrane contactor as defined in the attached claims.

[0013] With reference again to the two small membrane contactors illustrated in Figures 1 and 2 (both prior art), while these are excellent small membrane contactors, improvements in their construction and / or manufacture could drive down cost, enhance performance for certain applications, or both. Figure 1 shows the 1x3 contactor; it requires two welds, W 1 and W 2 to seal the cap to the body and the membrane cartridge. Figure 2 shows the 2x6 contactor; it has two caps C 1 and C 2 .

[0014] In at least one embodiment, a new or improved membrane contactor includes: a cap has an internally beveled surface and a cap port; a cup body has an externally beveled surface in sealing engagement with the internally beveled surface and a side port on a side of the cup body and an end port located on an end of the cup body; and a membrane cartridge is located within the cup body, is sealed to an open end of the cup body, and is in sealed fluid communication with the end port. Such an inventive contactor may be made by a method of making a membrane contactor includes the steps of: sealingly mating a perforated center of a membrane contactor with the end port of a cup body; sealingly joining an end of the membrane cartridge adjacent an open end of the cup body; and sealingly joining a beveled surface of the cap to a beveled external surface of the cup body.DESCRIPTION OF THE DRAWINGS

[0015] For the purpose of illustrating the invention, there is shown in the drawings prior contactors and a form that is presently preferred; it being understood, however, that this invention is not limited to the precise arrangements and instrumentalities shown in Figures 3A-C. Figure 1 is a prior art membrane contactor. Figure 2 is a prior art membrane contactor. Figures 3A-C show an embodiment of the inventive membrane contactor. DESCRIPTION OF THE INVENTION

[0016] Referring to Figures 3A-C, there is shown an embodiment of the inventive membrane contactor 10. Contactor 10 generally includes a cap 12, a cup body 14, and membrane cartridge 16. The membrane cartridge 16 may be located within the cup body 14.

[0017] The cap 12 and cup body 14 are sealingly joined by joint 13 along joining surfaces 13' and 13". Surface 13' may be an internally facing joining surface located on cap 12, and surface 13" may be an externally facing joining surface located on cup body 14. The joint 13 is illustrated as a scarf joint (i.e., surfaces 13' and 13" are beveled), but joint 13 may be a shear joint (i.e., surfaces 13' and 13" are parallel to the axis of the contactor 10), or a butt joint or any other combination of joint designs. Hereinafter, the contactor 10 will be illustrated with the scarf joint, but the shear joint may be used in place thereof.

[0018] Cap 12 may be generally cup shaped (e.g., circular cross-section) with an open end 18 and a closed end 20, see Figure 3B. Cap 12 may also include an internally beveled surface 13', a shoulder 26, a skirt 28, a headspace 30, and a cap port 32 with an opening 34 therethrough. Cap port 32 may be a nipple extending away from cap 12. Beveled surface 13' may have a shallow angle, for example <30°, or 4°-15°. Skirt 28 extends beyond joint 13, thereby concealing joint 13. Nipple is a sealable fitting, for example - a Luer (or medical) fitting, NPT, straight tube, compression, quick-connect, or any other suitable fitting.

[0019] Cup body 14 may be generally cup shaped (e.g., circular cross-section) with an open end 36 and a closed end 38, see Figure 3B. Cup body 14 may also include an externally beveled surface 13", a shoulder 40, a side port 42 with an opening 44 therethrough, and end port 46 with an opening 48 therethrough. Beveled surface 13" may complement the angle of beveled surface 13'. Side port 42 may be a nipple 47 extending away from the cup body 14. End port 46 may include a nipple extending away from the cup body 14. End port 46 also includes an inwardly extending nipple 50 with a mating external surface 52. Mating external surface 52 may be beveled. Mating external surface 52 may have a shallow angle, for example <30°, or 4°-15°. Nipple is a sealable fitting, for example - a Luer (or medical) fitting, NPT, straight tube, compression, quick-connect, or any other suitable fitting.

[0020] Membrane cartridge 16 generally includes a bundle of membranes (e.g., hollow fiber membranes) 54 surrounding and bonded to a perforated center tube 56, see Figure 3A. The cartridge 16 has a first end 58 and a second end 60. A plug 62 is disposed in the center tube 56 adjacent second end 60. A mating internal surface 64 is located at the first end of the perforated center tube 56 adjacent the first end 58. Mating internal surface 64 may be beveled. Mating internal surface 64 may complement the angle of mating external surface 52. The hollow fiber membranes of bundle 54 are closed at the first end 58 and open at the second end 60. The bundle 54 may be bonded to the center tube 56 by a potting material. Potting material (e.g., epoxy, polyurethane, thermoplastic polymer, and / or adhesive) may be formed into walls 66 at the first end 58 and the second end 60 of the cartridge 16.

[0021] Figure 3C illustrates that cartridge 16 may be made two-at-a-time, cartridge 16A and 16B. The membrane are wound around the center tube 56, so that the end of the membranes are closed 58A and 58B. If the membrane is a plurality of hollow fibers, the hollow fibers may be knit into a fabric (the lateral edges of the fabric will have closed or looped over ends) and then wound around the center tube 56. The membranes may be joined to the center tube 56 in a conventional fashion, i.e., potting at 66A, 66A / B, and 66B. Then, cartridge 16A and cartridge 16B are separated (e.g., cut apart) along line 68. Plugs 62 may be formed at the same time that the potting at 66A / B are formed.

[0022] When assembled, see Figure 3A, (or assembling), cartridge 16 is inserted into cup body 14 by engaging mating surface 64 of the center tube 56 with the mating surface 52 of the end port 46. These mating surfaces 52 and 64 must be held in sealing engagement when cartridge 16 is fixed to cup body 14. This sealing engagement may be accomplished by luer lock, press fit, interference fit, snap fit, threading, welding, and / or gluing. These mating surfaces 52 and 64 may be held in sealing engagement when cartridge 16 is fixed to cup body 14 by, for example, material 70 or a mechanism (not shown). The material 70 or the mechanism also seals the cartridge 16 and cup body 14 in fluid tight engagement. Material 70 may be any material conventionally known in the art. Such materials 70 include potting and / or glue. Such mechanisms include threading, clips, o-rings, snap fittings. Once the cartridge 16 is fixed into cup body 14, cap 12 is joined to the assembly of the cartridge 14 and cup body 16 via joint 13. Joint 13 is a fluid tight joint. Joint 13 may be a welded joint or glued joint. The welded joint may be formed by spin welding. Headspace 30 is formed between cap 12 and the assembly of cup body 14 and cartridge 16, when shoulder 26 of cap 12 rest on shoulder 40 of cup body 14.

[0023] In one embodiment, in operation, gas entrained liquid enters contactor 10 via end port 46 and travels along center tube 56 until blocked by plug 62. The gas entrained liquid exits the perforated center tube 56 and travels radially across the external surfaces of the hollow fiber membranes, and exits contactor 10 via side port 42 (this path defines the shell side). Vacuum or vacuum / sweep gas are introduced via cap port 32 and are in fluid communication with the lumens of the hollow fibers via headspace 30 (this path defines the tube side). The entrained gas is drawn from the liquid across the membranes and exits via cap port 32.

[0024] The present invention may be embodied in other forms without departing from the scope of the appended claims.

Claims

1. A membrane contactor comprises: a cap (12) has an internally facing joining surface (13') which is an internally beveled surface and a cap port; a cup body (14) has an externally facing joining surface (13") which is an externally beveled surface in sealing engagement with the internally facing joining surface, a side port (42) on a side of the cup body, and an end port (46) located on an end of the cup body, the end port (46) comprising an inwardly extending nipple (50) with a mating external surface (52) that is beveled; and a membrane cartridge (16) is located within the cup body, is sealed to an open end of the cup body, and is in sealed fluid communication with the end port; wherein the membrane cartridge includes a perforated center tube (56), a first end of the center tube having a mating internal surface (64) that is beveled, the mating internal surface (64) being adapted to sealingly join with the mating external surface (52) of the end port, and a second end of the center tube is plugged, and a bundle (54) of hollow fibers surrounding and potted to the center tube, the hollow fibers are closed adjacent the first end of the center tube and open adjacent the second end of the center tube, and wherein the first end of the center tube is held in sealing engagement with the end port by the cartridge being sealed to the cup body.

2. The membrane contactor of claim 1 wherein the sealing engagement of the internally facing joining surface and the externally facing joining surface is a scarf joint or a shear joint.

3. The membrane contactor of claim 1 wherein the cap further comprises an open end and a closed end, the internally beveled surface is located adjacent to the open end, and the cap port is located on the closed end.

4. The membrane contactor of claim 1 wherein the cap further comprises a skirt extending beyond and concealing the sealing engagement of the externally and internally beveled surfaces.

5. The membrane contactor of claim 1 further comprises a head space between the cap and the cup body and the membrane cartridge, the cap port being in fluid communication with the head space.

6. The membrane contactor of claim 1 wherein the cap port comprises a nipple extending away from the cap.

7. The membrane contactor of claim 1 wherein the end port includes an outwardly projection nipple.

8. The membrane contactor of claim 1 wherein the side port comprises a nipple extending away from the cup body.

9. A method of making the membrane contactor of any of claims 1-8, the method comprises the steps of: sealingly mating the perforated center tube of the membrane cartridge with the end port of the cup body by engaging the mating internal surface (64) of the membrane cartridge with the mating external surface (52) of the end port; sealingly joining the end of the membrane cartridge adjacent the open end of the cup body; and sealingly joining the internally beveled surface of the cap to the externally beveled surface of the cup body.

10. The method of claim 9 wherein sealingly mating includes a luer fit, a press fit, an interference fit, a snap fit, a thread fit, a weld fit, or a glue fit.

11. The method of claim 9 wherein sealingly joining the end of the membrane cartridge to the cup body includes potting, gluing, threading, or O-ring sealing.

12. The method of claim 9 wherein sealingly joining the beveled surfaces includes spin welding and gluing.