Spinning beam

Abstract

The present disclosure relates to a spinning beam for producing hollow fiber membranes in a phase inversion process and to a method of using the spinning beam.

Description

Technical Field

[0001] The present disclosure relates to a spinning beam for producing hollow fiber membranes in a phase inversion process, the spinning beam comprising a plurality of spinnerets. Background Art

[0002] Semipermeable hollow fiber membranes used in medical devices such as capillary dialyzers and capillary filters are mostly manufactured using a phase inversion process. A spinneret having a nozzle with two concentric orifices, an outer ring slit and a central hole is usually used. The polymer solution is extruded into a settling tank through the outer ring slit of the nozzle, while the central fluid is extruded through the inner hole of the nozzle.

[0003] The spinning train includes a plurality of spinnerets implemented in a spinning machine for producing a plurality of hollow fiber membranes which are bundled into a fiber bundle. Hundreds of spinnerets are arranged in one spinneret, and each spinneret is supplied with a polymer solution and a core fluid separately.

[0004] Spinneret generally comprises a spinning beam, which is a rectangular steel bar with a rectangular notch (pocket) for accommodating each spinneret. The notches are arranged side by side on the spinning beam. The number of spinnerets is limited by the length of the spinning beam. The spinneret is inserted into the notch and fixed in place using an eccentric screw. Water circulates through the channel provided in the spinning beam to control the temperature of the fluid supplied to the spinneret so that the fluid has a desired temperature when they are extruded through the orifice of the spinneret. As the eccentric screw moves the rectangular spinneret body to one side of the rectangular notch and the spinneret has only one wall contacting the wall of the notch, the heat transfer from the spinning beam to the spinneret and the fluid in the spinneret is impaired respectively.

[0005] A spinning wheel is a specially designed structure that includes subunits for depositing, washing, drying, crimping and collecting the fibers. This train of machines requires a large investment. Increasing spinning capacity requires duplication of such machines and therefore duplication of the investment.

[0006] US 3081490 A discloses a spinneret for producing hollow filaments, which has six spinning holes for making a line with six independent filaments. The spinneret is composed of two circular plates, which are firmly held together by bushing screws. The plate is provided with a central spinning orifice, which has two alignment holes or positioning holes for dowels and a cylindrical conduit or hole coaxial with the spinning orifice and larger in diameter. The conduit extends from the upper surface of the plate to the upper end of the spinneret orifice. The lower side of the plate is provided with a circular recess, which forms a supply chamber for a spinning solution or melt and has a hole terminating in the recess, and the spinning solution or melt is supplied to the recess through the hole. A supply passage leading to the hole is drilled in the plate for supplying a gaseous or liquid medium to the inside of the hollow pin through an opening. The pin terminates in a capillary and is fixed to the hole of the plate by a hollow screw, and is concentrically located in a cylindrical hole having a diameter greater than that of the pin. The pin is provided with a widened bearing surface which engages under the plate when the pin is mounted in the hole. The position of the capillary duct in the spinning orifice can be adjusted axially by means of a packing under the screw head and on the bearing surface. When the screw is tightened, a thin aluminum packing ring between the plates seals the supply chamber. The pin is firmly anchored in the plates and projects through the hole in the plates. The hollow pin is provided with a lateral opening starting from the reduced part of the pin housing. At the level of the capillary attachment, the pin can be equipped with a centering part, whose four radial projections are a precise sliding fit in the cylindrical duct in the plate.

[0007] JP 6507914 B2 provides a production method and production equipment for glass fiber, which can easily supply gas to form a hollow portion in the glass fiber. The production method of glass fiber with a hollow portion includes pulling out molten glass in a bushing from a nozzle formed at the bottom of the bushing. The hollow portion is formed by inflow bubbles, which are generated by electrolysis of components in the molten glass in the bushing. The production equipment includes a bushing with a nozzle at the bottom, the molten glass is pulled out of the nozzle, and electrodes (anode and cathode) for applying a DC voltage to the molten glass in the bushing.

[0008] JP 2006272271 A provides a method and apparatus for producing a porous hollow fiber membrane by dry-wet spinning. In the method, the temperature of the spinning nozzle and the stock solution discharge temperature are set to the dew point temperature of the idling part or lower, and at the same time, the bottom surface temperature near the stock solution discharge port is maintained at the dew point temperature or higher by a heating device, and the dew point temperature is +50°C or lower. The heating device is provided with a cylindrical or annular annular heat conductor, which is arranged near the stock solution discharge port of the spinning nozzle and contacts the bottom surface of the nozzle, a cylindrical electric heater is arranged on the outer peripheral surface of the annular heat conductor, and a support plate is fixed to the periphery of the electric heater and the annular heat conductor, and is fixed to the bottom of the nozzle at the same time.

[0009] CN 102517652 A discloses an assembled spinneret with multiple spinning nozzles, including an upper spinneret, a middle spinneret and a lower spinneret, wherein the upper spinneret is provided with an internal condensation liquid inlet, a constant temperature liquid inlet, a film liquid inlet and a constant temperature liquid outlet. The internal condensation liquid inlet is connected to the middle spinneret liquid delivery disk on the middle spinneret through the upper spinneret liquid delivery sleeve. The middle spinneret liquid delivery sleeve is installed below the middle spinneret liquid delivery disk. The middle spinneret liquid delivery sleeve is connected to the spinning nozzle. The upper spinneret, the middle spinneret and the lower spinneret are provided with a film liquid channel inside, and the middle spinneret and the lower spinneret are provided with a constant temperature liquid channel inside. Multiple spinning nozzles are assembled on the spinneret, so that the spinneret structure is simple, compact and integrated. The film-making liquid channel, the internal condensation liquid channel and the constant temperature liquid channel are evenly distributed, and the liquid flows smoothly, so that the sealing and pressure resistance of the spinneret are achieved.

[0010] EP 3147024 A1 discloses a method for producing a hollow fiber polymer membrane having an isoporous inner layer and a porous outer layer. The method includes providing a polymer solution of at least one amphiphilic block copolymer in a solvent; extruding the polymer solution (coating) through a first annular die in a spinneret, while extruding a core airflow through at least one orifice surrounded by the first die, and extruding a sheath liquid containing at least one precipitate into the air from a second annular die surrounding the first die, and then entering a water precipitation tank, thereby providing a gap between the spinneret and the precipitation solution, the polymer solution extruded through the gap is surrounded by the sheath liquid and surrounds the core airflow, and finally the spinning solution is precipitated in the precipitation tank to form a hollow fiber polymer membrane.

[0011] It is an object of the present disclosure to provide an option for capacity expansion of a spinning wheel that does not require duplication of the entire equipment of the spinning wheel and allows retrofitting of existing spinning wheels.It is another object of the present disclosure to provide an improved spinning beam. Summary of the invention

[0012] The present disclosure provides a spinning beam with a honeycomb structure, each honeycomb structure having six hexagonal seats for respective spinnerets arranged around a central hexagonal feed unit, the hexagonal feed unit being configured to supply polymer solution and a central fluid for producing a hollow fiber membrane to the respective spinnerets.

[0013] The present disclosure also provides a hexagonal spinneret for installation in the hexagonal seat of the spinning beam of the present disclosure.

[0014] The present disclosure also provides a spinning unit, comprising a spinning beam of the present disclosure and a plurality of spinnerets and a supply unit. The spinnerets are present in each hexagonal seat, and the supply unit is connected to each central feed unit. A method for producing a hollow fiber membrane using the spinning unit is also provided.

[0015] The spinning unit is intended to increase the capacity of a spinning wheel compared to a conventional device with individual spinning nozzles. The number of pumps required to supply the polymer solution and the center fluid to the spinnerets separately is significantly reduced, and the modification of existing spinning wheels requires almost no investment. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A perspective schematic diagram of an embodiment of a spinning unit of the present disclosure is shown;

[0017] Figure 2 yes Figure 1 A top view of a spinning unit;

[0018] Figure 3 yes Figure 1 A cross-sectional view of one of the honeycomb structures of the spinning unit;

[0019] Figure 4 is a partial perspective view of one embodiment of a spinning beam of the present disclosure;

[0020] Figure 5 A top view and a cross-sectional view of one embodiment of a spinneret body of the present disclosure are shown. DETAILED DESCRIPTION

[0021] A spinning beam with a honeycomb structure is provided. Each honeycomb structure has six hexagonal seats for respective spinnerets arranged around a central hexagonal feed unit. The central hexagonal feed unit is configured to supply a polymer solution and a central fluid for producing a hollow fiber membrane to each spinneret.

[0022] The present disclosure provides a spinning beam including a plurality of honeycomb structures, each honeycomb structure including six hexagonal spinneret seats arranged around a central hexagonal feed unit. The feed unit includes both a feed end for a polymer solution and a feed end for a central fluid on each of its six surfaces, and is configured to receive a supply pipe, the supply pipe including a conduit for the polymer solution and a conduit for the central fluid, the conduit for the polymer solution and the conduit for the central fluid corresponding to the feed end for the polymer solution and the feed end for the central fluid of the feed unit, respectively. The feed unit also includes an electric heating element arranged at its bottom.

[0023] Due to the hexagonal form of the spinneret holder and the feed unit, the conduits for the polymer solution and the central fluid provided in one wall of the body of each spinneret are automatically aligned with the conduits for the polymer solution and the central fluid provided in each of the six walls of the central feed unit. In addition, the conduits for the polymer solution and the conduits for the central fluid in the supply pipe are automatically aligned with the conduits for the polymer solution and the conduits for the central fluid provided in each of the six walls of the central feed unit. This greatly facilitates the assembly of the spinning unit, since it is not necessary to adjust the orientation of the spinneret and the supply pipe separately when mounting them on the spinning beam.

[0024] In one embodiment, each hexagonal spinneret seat gradually narrows towards the bottom of the seat.In one embodiment, the inwall of each spinneret seat is with an angle in the range of 1 ° to 15 °, such as 5 ° to 15 ° or 10 to 15 °, and gradually narrows towards its bottom.Because the outer contour of each spinneret matches the inner contour of the seat, the spinneret is fastened in the seat by self-locking.When the spinneret body was fastened on the seat, each sidewall contact seat wall of six sidewalls of the spinneret, thereby improved the heat transfer from the spinning beam to the spinneret.

[0025] The polymer solution and the center fluid for producing the hollow fiber membrane are supplied from the central feed unit to the adjacent spinneret through a conduit provided in the wall of the central feed unit. An electric heating element is installed below the central feed unit. This allows the temperature of the polymer solution and the center fluid in the feed unit to be controlled separately before the polymer solution and the center fluid are conveyed to the spinneret.

[0026] The disclosed spinning beam allows for an increase in the number of spinnerets placed on a given length and width of the spinning beam compared to conventional spinning beam designs. The number of spinnerets can easily be tripled or increased more. The spinning beam can have a more compact design because the passages through the spinning beam for circulating a heating fluid are eliminated and replaced by electrical heating elements located below the hexagonal feed unit.

[0027] In one embodiment of the spinning beam, each honeycomb structure of the spinning beam contacts at least two other honeycomb structures of the spinning beam. In other embodiments, at least three of the spinneret holders of each honeycomb structure of the spinning beam abut against the spinneret holder of another honeycomb structure of the spinning beam.

[0028] The present disclosure also provides a hexagonal spinneret for mounting in the hexagonal seat of the spinning beam of the present disclosure. The hexagonal spinneret has two concentric orifices, an outer annular slit and a central orifice ("double-slit nozzle").

[0029] The present disclosure provides a spinneret for producing a hollow fiber membrane, comprising a spinneret body and a spinneret core.

[0030] The spinneret body has a hexagonal outer contour and an axisymmetric central cavity, a conduit for a polymer solution and a conduit for a central fluid, and an orifice at the bottom of the central cavity, the conduits connecting the central cavity to one of the outer surfaces of the spinneret body.

[0031] Spinning head comprises the spinning head body with hexagonal outer profile.In one embodiment, the spinning head body gradually narrows from its top towards its bottom.In one embodiment, the outside of the spinning head body gradually narrows towards its bottom with an angle in the range of 1 ° to 15 °.The cone angle, that is, the aperture of the corresponding hexagonal pyramid, is in the range of 1 ° to 15 °, such as 5 ° to 15 °, or 10 ° to 15 °.The conical outer profile of spinning head makes it self-locking in the same conical spinning head seat of spinning beam.The cone angle is smaller, and the required force of spinning head being disassembled from spinning beam is just greater.The angle at which self-locking occurs depends on various parameters, such as the shape of surface quality, material pairing and spinning head etc.

[0032] The spinneret body has a conduit for the polymer solution and a conduit for the central fluid in one wall of the spinneret body. When the spinneret is inserted into the spinneret holder of the honeycomb structure, the wall with the conduit contacts the outer wall of the central supply unit of the honeycomb structure. The conduit for the polymer solution is connected to the circumferential cavity for the polymer solution. The mouth of the circumferential cavity for the polymer solution forms the outer annular seam of the spinneret double-slit nozzle.

[0033] In one embodiment, the spinneret body has sealing gaskets on the outer surface of the spinneret body surrounding the orifices of the conduit for the polymer solution and the conduit for the center fluid.

[0034] The spinneret also includes an axisymmetric spinneret core in the spinneret body. The spinneret core is arranged in the central cavity of the spinneret body, and the spinneret body and the spinneret core together define a circumferential cavity for the central fluid and a circumferential cavity for the polymer solution in the spinneret.

[0035] One or more conduits connect the circumferential cavity for the central fluid to the central cavity of the spinneret core, which extends along the central longitudinal axis of the spinneret core. The capillary connects the central cavity to the orifice of the spinneret body. The capillary mouth forms the inner orifice of the spinneret double-slit nozzle.

[0036] The spinneret core has an axial hole with fine threads. An adjusting screw is located in the axial hole of the spinneret core. The adjusting screw seals the top of the central cavity of the spinneret core and is configured to adjust the flow of the center fluid through the spinneret core. When the adjusting screw is lowered, it partially blocks the conduit for the center fluid, restricting the flow through the conduit.

[0037] The present disclosure also provides a spinning unit, which comprises the spinning beam of the present disclosure and a plurality of spinnerets and a supply unit. The spinnerets are present in each hexagonal seat, and the feed unit is connected to each central supply unit.

[0038] The spinning unit of the present disclosure comprises the spinning beam of the present disclosure, a plurality of spinnerets of the present disclosure and a plurality of supply tubes, each spinneret is fastened to a spinneret holder of the spinning beam, and each supply tube is fastened in a feed unit of the spinning beam.

[0039] In one embodiment, the supply pipe has a feed pipe for the polymer solution and a feed pipe for the core fluid. The feed pipes are coaxial, and the feed pipe for the polymer solution is located inside the feed pipe for the core fluid.

[0040] In one embodiment, the feed tube for the central fluid is directly connected to the central fluid reservoir, and the feed tube for the polymer solution is connected to the polymer solution reservoir via a connecting tube. The connecting tube penetrates the wall of the outer tube.

[0041] A conduit for polymer solution and a conduit for center fluid are arranged at the bottom of the supply tube, and the supply tube is used to supply the polymer solution and the center fluid to the spinneret, respectively. When the supply tube is inserted into the central hexagonal feed unit of the spinning beam honeycomb structure, the orifices of the conduits match the corresponding orifices of the conduits in the wall of the center feed unit.

[0042] The spinning unit of the present disclosure significantly reduces the space requirement of the spinning beam machine. In addition, by replacing the conventional spinning unit with the spinning unit of the present disclosure, the spinning capacity of the spinning wheel can be increased without requiring additional space.

[0043] Another advantage of the spinning unit of the present invention is that only one pump for the polymer solution and one pump for the center fluid are required for each honeycomb structure, i.e., six spinnerets. Compared to a conventional spinning machine producing the same number of fibers, only a fraction of the number of pumps is required.

[0044] Another advantage of the spinning unit disclosed herein is related to its modular design, which allows individual spinnerets and supply units to be replaced separately. Maintenance of the spinning unit is thus greatly facilitated.

[0045] Furthermore, the center fluid flow through each individual spinneret can be calibrated independently of the center fluid flow through the other spinnerets by means of an adjustment screw. This calibration can even be performed on each spinneret before it is mounted on the spinning beam, ensuring that each center fluid flow through each spinneret in the spinning unit is identical. Since the flow rate of the center fluid through the spinneret affects the inner diameter of the produced hollow fiber membrane, this is critical to ensure a constant fiber size.

[0046] The present disclosure also provides a method for producing a hollow fiber membrane, comprising: simultaneously supplying a polymer solution and a center fluid to a feed unit of a spinning unit of the present disclosure; and simultaneously extruding the polymer solution through an orifice and the center fluid through a capillary of a spinneret of the spinning unit of the present disclosure.

[0047] Suitable polymer solutions and suitable center fluids for producing semipermeable hollow fiber membranes are well known in the art. For example, a solution comprising: 1) at least one polysulfone, polyethersulfone or polyarylethersulfone, and 2) at least one polyvinylpyrrolidone dissolved in 3) a mixture of N-methyl-2-pyrrolidone (NMP) and water can be used as the polymer solution, and a mixture of water and NMP can be used as the center fluid.

[0048] The spinning unit of the present disclosure will now be further explained with reference to the accompanying drawings.

[0049] Figure 1 A stereogram of an exemplary embodiment of a spinning unit 100 of the present disclosure is shown. The spinning beam 200 has a plurality of honeycomb structures 210. Each honeycomb structure 210 includes six hexagonal spinneret seats 220 arranged around a central hexagonal feed unit 230. A hexagonal spinneret 300 is present in each hexagonal spinneret seat 220; a supply tube 400 is connected to each hexagonal feed unit 230. Each supply tube 400 is connected to a polymer solution reservoir and a central fluid reservoir (not shown). An adjustment screw 324 is present on each spinneret 300, allowing the flow of the central fluid through each spinneret 300 to be individually adjusted.

[0050] Figure 2 yes Figure 1 A top view of the spinning unit 100 is shown.

[0051] Figure 3 yes Figure 2 The cross-sectional view (AA section) of the spinning unit 100 shown shows a longitudinal section through the center of the honeycomb structure 210 , which passes through the center of the central hexagonal feed unit 230 and two of the six hexagonal spinneret holders 220 .

[0052] The supply pipe 400 is inserted into the central hexagonal feed unit 230. The supply pipe 400 has a feed pipe 410 for the polymer solution and a feed pipe 420 for the central fluid. The feed pipes 410, 420 are coaxial, and the feed pipe 410 for the polymer solution is located inside the feed pipe 420 for the central fluid. The feed pipe 420 for the central fluid is directly connected to the central fluid reservoir, and the feed pipe 410 for the polymer solution is connected to the polymer solution reservoir through a connecting pipe 412. The connecting pipe 412 is connected to the feed pipe 410 for the polymer solution at the upper end of the feed pipe 410. At the bottom of the supply pipe 400, a conduit 411 for the polymer solution and a conduit 421 for the central fluid are provided for supplying the spinneret 300.

[0053] The electric heating element 233 is arranged below the central hexagonal feed unit 230 and allows the temperature of the polymer solution and the central fluid to be controlled separately. The central hexagonal feed unit 230 has a feed end 231 for the polymer solution and a feed end 232 for the central fluid in each of its walls to supply the polymer solution and the central fluid to the spinneret 300, respectively.

[0054] In the body 310 of each spinneret 300, a corresponding conduit 311 for polymer solution and a conduit 312 for central fluid are provided, wherein it contacts the wall of the central feed unit 230. On the outer surface of the spinneret body 310, between the orifices of the conduits 311, 312 and the corresponding orifices of the ports 231, 232 of the feed unit 230, a sealing gasket 314 is provided. Each spinneret 300 has a spinneret core 320. The spinneret body 310 and the spinneret core 320 together define a circumferential cavity 330 for central fluid and a circumferential cavity 340 for polymer solution. One or more conduits 321 for central fluid connect the circumferential cavity 330 with the central cavity 322 of the spinneret core 320. The capillary 323 connects the central cavity 322 to the nozzle 313 of the spinneret 300. The flow of the center fluid through the spinneret core 320 can be adjusted by the adjustment screw 324. When the adjustment screw 324 is turned downward, it partially seals the conduit 321 for the center fluid, restricting the flow through the conduit 321. The conduit 311 for the polymer solution is connected to the circumferential cavity 340 for the polymer solution. The mouth of the cavity 340 forms the outer annular slit of the nozzle 313.

[0055] Figure 4 2 is a partial perspective view of an embodiment of a spinning beam 200 of the present disclosure. The spinning beam 200 has a plurality of honeycomb structures 210 arranged adjacent to each other. As shown in the figure, the honeycomb structures 210 can form a dense packing because their outer contours match each other. Up to six honeycomb structures 210 can be arranged around the central honeycomb structure 210, provided that the size of the spinning beam 200 is large enough.

[0056] Each honeycomb structure 210 has six conical hexagonal spinneret seats 220 arranged around a central hexagonal feed unit 230, which gradually narrows toward its top. A feed end 231 for polymer solution and a feed end 232 for the central fluid are present in each of the six walls of the central feed unit 230. The central supply unit 310 has a central hole for inserting a supply pipe. In an exemplary embodiment, the diameter of the hole ranges from 10 mm to 15 mm, such as 12 mm.

[0057] Figure 5 A top view and a cross-sectional view (AA section) of one embodiment of a spinneret body 310 of the present disclosure are shown. The spinneret body 310 has a hexagonal outer profile and an axisymmetric central cavity 315 defined by a drilled hole. The spinneret body 310 includes a conduit 311 for a polymer solution and a conduit 312 for a central fluid, the conduits connecting the central cavity 315 to one of the outer surfaces of the spinneret body 310. A sealing gasket 314 is provided on the outer surface of the spinneret body 310 to prevent fluid leakage from the conduits 311, 312 when the spinneret body 310 is connected to a feed unit. A nozzle 313 is present at the bottom of the spinneret body 310. At Figure 5 In the example shown, the outer wall surface of the spinneret body 310 tapers at an angle of 12. The tapered form of the spinneret body 310 allows the spinneret to self-lock in a spinneret seat that is also tapered.

[0058] Reference Symbols List

[0059] 100 spinning units

[0060] 200 Spinning Beam

[0061] 210 honeycomb structure

[0062] 220 hexagonal spinneret seat

[0063] 230 Hexagonal Feed Unit

[0064] 231 Feed end for polymer solution

[0065] 232 Feed end for central fluid

[0066] 233 Electric heating element

[0067] 300 hexagonal spinneret

[0068] 310 spinneret body

[0069] 311 Catheter for polymer solution

[0070] 312 Conduit for central fluid

[0071] 313 Nozzle

[0072] 314 Sealing Washer

[0073] 315 center cavity

[0074] 320 spinneret core

[0075] 321 Conduit for central fluid

[0076] 322 Cavity for central fluid

[0077] 323 Capillary

[0078] 324 Adjusting screw

[0079] 330 Circumferential cavity for central fluid

[0080] 340 Circumferential cavity for polymer solution

[0081] 400 supply pipe

[0082] 410 Feeding tube for polymer solution

[0083] 411 Catheter for polymer solution

[0084] 412 connecting pipe

[0085] 420 Feed pipe for center fluid

[0086] 421Conduit for central fluid

Claims

1. A spinning unit (100), comprising: A spinning beam (200) comprising a plurality of honeycomb structures (210), each honeycomb structure (210) comprising six hexagonal spinneret seats (220) arranged around a central hexagonal feed unit (230), the feed unit (230) comprising both a feed end (231) for a polymer solution and a feed end (232) for a central fluid on each of its six surfaces, the feed unit (230) being configured to receive a supply pipe (400) comprising a conduit (411) for a polymer solution and a conduit (421) for a central fluid, the conduit (411) for a polymer solution and the conduit (421) for a central fluid corresponding to the feed end (231) for the polymer solution and the feed end (232) for the central fluid of the feed unit (230), respectively; and the feed unit (230) comprising an electric heating element (233) arranged at the bottom thereof; A plurality of spinnerets (300), each spinneret (300) comprising: A spinneret body (310) having a hexagonal outer profile and an axisymmetric central cavity (315), and comprising a conduit (311) for a polymer solution, a conduit (312) for a central fluid, and an orifice (313) at the bottom of the central cavity (315), wherein the conduits (311, 312) connect the central cavity (315) to an outer surface of the spinneret body (310); and A spinneret core (320), the spinneret core (320) being arranged in the central cavity (315) of the spinneret body (310), the spinneret body (310) and the spinneret core (320) together defining a circumferential cavity (330) for a central fluid and a circumferential cavity (340) for a polymer solution, the spinneret core (320) comprising one or more conduits (321) for the central fluid, the one or more conduits (321) connecting the circumferential cavity (330) for the central fluid to the central cavity (322) of the spinneret core (320); and a capillary tube (323) connecting the central cavity (322) of the spinneret core (320) to the orifice (313) of the spinneret body (310); and an adjusting screw (324) sealing the top of the central cavity (322) of the spinneret core (320) and configured to adjust the flow of the center fluid through the spinneret core (320) by partially sealing the one or more conduits (321) for the center fluid when the adjusting screw (324) is turned downward; and a plurality of supply tubes (400); wherein each spinneret (300) is fastened in a spinneret holder (220) of the spinning beam (200), and each supply tube (400) is fastened in a feed unit (230) of the spinning beam (200); Wherein, each honeycomb structure (210) of the spinning beam (200) contacts at least two other honeycomb structures (210) of the spinning beam (200); and at least three of the spinneret seats (220) of each honeycomb structure (210) of the spinning beam (200) are closely attached to the spinneret seat (220) of another honeycomb structure (210) of the spinning beam (200).

2. The spinning unit (100) according to claim 1, wherein: The supply pipe (400) has a feed pipe (410) for the polymer solution and a feed pipe (420) for the center fluid, the feed pipes (410, 420) are coaxial, the feed pipe (410) for the polymer solution is located inside the feed pipe (420) for the center fluid, and the conduit (411) for the polymer solution and the conduit (421) for the center fluid are arranged at the bottom of the supply pipe (400) for supplying the spinneret (300).

3. The spinning unit (100) according to claim 2, wherein: The feed pipe (420) for the central fluid is directly connected to a central fluid reservoir, and the feed pipe (410) for the polymer solution is connected to a polymer solution reservoir through a connecting pipe (412).

4. The spinning unit (100) according to any one of claims 1 to 3, wherein: The inner wall of each spinneret seat (220) gradually narrows toward its bottom at an angle ranging from 1° to 15°.

5. The spinning unit (100) according to any one of claims 1 to 3, wherein: The outer surface of the spinneret body (310) gradually narrows toward its bottom at an angle ranging from 1° to 15°.

6. The spinning unit (100) according to any one of claims 1 to 3, wherein: The spinneret body (310) has a sealing gasket (314) surrounding the orifices of the conduit (311) for the polymer solution and the conduit (312) for the center fluid on the outer surface of the spinneret body (310).

7. A method for producing a hollow fiber membrane, comprising: A polymer solution and a center fluid are simultaneously supplied to a feeding unit (230) of a spinning unit (100) according to any one of claims 1 to 6; the polymer solution is extruded through an orifice (313) and the center fluid is simultaneously extruded through the capillary (323) of the spinneret (300) of the spinning unit (100).

8. The method according to claim 7, wherein: The polymer solution includes: 1) polysulfone, polyethersulfone or polyarylethersulfone; and 2) at least one polyvinylpyrrolidone.

9. The method according to claim 8, wherein: The polymer solution includes: 3) N-methyl-2-pyrrolidone.

10. The method according to claim 9, wherein: The polymer solution also includes water.

11. The method according to any one of claims 7 to 10, wherein: The central fluid includes: water.

12. The method according to claim 11, wherein: The center fluid also includes N-methyl-2-pyrrolidone.

Images