Hollow fiber membrane module for enriching nitrogen in air

Abstract

The utility model discloses a hollow fiber membrane assembly for enriching nitrogen in air. The hollow fiber membrane assembly comprises a membrane shell, a fiber membrane tow and a cylindrical airflow distributor, wherein a convex thread-shaped airflow baffle is arranged on the inner side of the membrane shell; the top of the airflow distributor is provided with a main air inlet, and a plurality of gas distribution holes are axially and uniformly distributed in the pipe wall; and the distance between the hollow fiber membrane and the membrane shell of which the inner side is provided with the convex thread-shaped airflow baffle is twice the outer diameter of the fiber. The membrane component disclosed by the utility model is compact in structure, does not need an additional power device, and can effectively improve the mass transfer efficiency in the membrane-method air nitrogen production process and reduce the energy consumption loss.

Description

TECHNICAL FIELD

[0001] The utility model relates to a kind of hollow fiber membrane assemblies for air nitrogen enrichment, belong to gas separation technical field. BACKGROUND

[0002] Nitrogen (N2) as a common chemical substance. In the field of industrial production, food preservation, drug preparation, biological specimen preservation, gas replacement is widely used.

[0003] The separation of nitrogen and oxygen in air has wide applications in industry, including medical oxygen production, nitrogen protection gas preparation and air purification process. Currently, low-temperature separation, adsorption separation and other methods are widely used in the market, but these methods have high energy consumption and complex equipment.

[0004] Hollow fiber membrane as a kind of high-efficiency separation device, with its large unit volume separation area, simple process and modular characteristics, become the important development direction of air nitrogen enrichment field. The membrane is connected to the shell by pouring resin, and the pouring resin seals the shell side of the assembly, which allows the assembly to be used with the shell or hole side feed. However, the current hollow fiber membrane still has deficiencies in high selectivity and high throughput uniformity, and new membrane assemblies need to be developed to meet the demand for more efficient separation. SUMMARY

[0005] To solve the problems existing in the prior art, the utility model provides a kind of hollow fiber membrane assembly for air nitrogen enrichment, compact structure, without additional power device, can effectively improve the mass transfer efficiency of membrane method air nitrogen production process, reduce energy loss.

[0006] The technical scheme of the utility model is as follows:

[0007] The utility model provides a kind of hollow fiber membrane assembly for air nitrogen enrichment, including cylindrical airflow distributor and the membrane shell of hollow structure;Two ends of airflow distributor respectively pass out of membrane shell, wherein two ends form main air inlet and air outlet respectively, airflow distributor side wall is evenly distributed with several gas distribution holes along the axial direction;Membrane shell inside is raised to form thread-shaped airflow baffle towards airflow distributor, a plurality of parallel fiber membrane bundles are arranged at the cavity between membrane shell and airflow distributor,

[0008] Further, the side air inlet and the side air outlet are further provided on the side wall of the membrane shell, and the side air inlet and the side air outlet are respectively located at the two end portions of the membrane shell. The side air outlet can be connected to a vacuum pump.

[0009] Further, the fiber membrane bundle is arranged in parallel with the airflow distributor, and the fiber membrane bundle is of a hollow structure. The two ends of the fiber membrane bundle are fixed in the membrane shell by casting with an epoxy resin sealing layer. The thickness of the epoxy resin sealing layer is 3-5 mm.

[0010] Further, the distance between the convex part of the air flow baffle and the fiber membrane filament bundle near the outermost side of the air flow baffle is 2 times the outer diameter of the fiber.

[0011] Further, the gas distribution hole is a tapered diffusion hole.

[0012] The utility model has the following beneficial effects:

[0013] 1, the utility model discloses a kind of hollow fiber membrane assemblies for air nitrogen enrichment, because setting towards air flow distributor convex screw thread air flow baffle in membrane shell inside, fiber membrane filament bundle is arranged at the cavity between membrane shell and air flow distributor, break through the mass transfer limit of traditional axial laminar flow, significantly increase air-membrane interface contact area and mixing intensity, the permeation rate difference of oxygen and nitrogen is maximized, without additional power device.

[0014] 2, the utility model discloses a kind of hollow fiber membrane assemblies for air nitrogen enrichment, compact structure, can effectively improve the mass transfer efficiency of membrane method air nitrogen production process, reduce energy consumption loss. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 It is the structure diagram of the utility model for a kind of hollow fiber membrane assemblies for air nitrogen enrichment.

[0016] Reference signs are shown in the drawing as follows:

[0017] 2-main air inlet, 3-membrane shell, 4-gas distribution hole, 5-fiber membrane filament bundle, 6-air flow baffle, 7-tube side air inlet, 8-tube side air outlet, 9-air flow distributor, 10-epoxy resin sealing layer. DETAILED DESCRIPTION

[0018] The utility model will be specifically explained in detail in connection with the drawing and specific embodiment.

[0019] Reference Figure 1A hollow fiber membrane module for air nitrogen enrichment, comprising a cylindrical gas flow distributor 9 and a membrane shell 3 in a hollow structure, in this embodiment, the membrane shell 3 is a hollow cylinder, but is not limited to a cylinder, and can be any hollow structure such as a cuboid, a polyhedron, etc.; the membrane shell 3 is wrapped outside the gas flow distributor 9, and a space is formed between the membrane shell 3 and the gas flow distributor 9; the gas flow distributor 9 is a long strip-shaped cylindrical structure, and its two ends respectively pass out of the membrane shell 3, one end of which forms a main air inlet 2; the side wall of the gas flow distributor 9 is uniformly distributed with a plurality of gas distribution holes 4 along the axial direction; the inner side of the membrane shell 3 is protruded towards the gas flow distributor 9 to form a thread-shaped gas flow baffle 6; after the gas diffuses through the gas flow distributor 9, the gas multi-stage spiral flow is induced by the spiral gas flow baffle 6, and uniform spiral propulsion type gas flow distribution is formed; a plurality of parallel fiber membrane bundles 5 are arranged in the cavity between the membrane shell 3 and the gas flow distributor 9; and the side wall of the membrane shell 3 is further provided with an air outlet 8 away from the end where the main air inlet 2 is arranged; the fiber membrane bundle 5 separates the diffused gas, enriches nitrogen, and at the same time, oxygen and other impurity gases can penetrate through the fiber membrane bundle 5 and be discharged through the air outlet 8.

[0020] As a preferred embodiment, the side wall of the membrane shell 3 is further provided with a side air inlet 7, and the side air inlet 7 and the side air outlet 8 are respectively arranged at the two end portions of the membrane shell 3; the side air inlet 7 is connected to a vacuum pump, and the gas entering through the side air inlet 7 can apply a flow rate to the permeation side gas, thereby facilitating the collection of the permeation side gas.

[0021] As a preferred embodiment, the fiber membrane bundle 5 is arranged in parallel with the gas flow distributor 9, and the two ends of the fiber membrane bundle 5 are fixed in the membrane shell 3 by casting through an epoxy resin sealing layer 10; the fiber membrane bundle 5 arranged in the interior of the membrane shell 3 is in a hollow structure, and the two ends of the fiber membrane bundle 5 respectively pass out of the vertically arranged epoxy resin sealing layer 10, so that one end of the fiber membrane bundle 5 is in communication with the side air inlet 7; after the epoxy resin sealing layer 10 is cured, an airtight partition is formed; at this time, the gas entering through the side air inlet 7 is blocked by the epoxy resin sealing layer 10, and the gas only passes through the interior of the fiber membrane bundle 5, and does not flow to the outside of the fiber membrane bundle 5, thereby avoiding mixing with the gas entering through the main air inlet 2; the thickness of the epoxy resin sealing layer 10 is 3-5 mm.

[0022] As a preferred embodiment, the distance between the protruding portion of the gas flow baffle 6 and the fiber membrane bundle 5 closest to the outermost side of the gas flow baffle 6 is 2 times the outer diameter of the fiber, so as to ensure that the fiber membrane bundle 5 does not collide with the membrane shell 3 and is broken due to changes in the flow rate of the gas during use.

[0023] As a preferred embodiment, the gas distribution hole 4 is a tapered diffusion hole, and the arrangement of the tapered diffusion hole can realize multi-stage diffusion of the gas flowing through the gas flow distributor 9 to the position of the fiber membrane bundle 5.

[0024] The working principle of the utility model is:

[0025] The gas to be enriched with nitrogen uniformly flows radially after entering the gas flow distributor 9 from the main gas inlet 2, diffuses from the gas flow distributor 9 to the outside of the fiber membrane filament bundle 5 through the gas distribution holes 4, collides with the spiral baffle 6 after diffusion, and forms a uniform spiral propelling gas flow distribution; the gas flow flows along the outside of the fiber membrane filament bundle 5 in the axial direction, fully contacts the surface of the fiber membrane filament bundle 5, and the nitrogen is enriched in the gas flow distributor 9 and then discharged through the other end gas outlet, the oxygen and other impurities in the air that pass through the fiber membrane filament bundle 5 enter the inside of the fiber membrane filament bundle 5, and finally are discharged through the side gas outlet 8.

[0026] A vacuum pump is connected at the side gas outlet 8, and the gas that enters the inside of the fiber membrane filament bundle 5 through the side gas inlet 7 is subjected to a flow rate by the vacuum pump, so that the oxygen and other impurities in the air that enter the inside of the fiber membrane filament bundle 5 are continuously discharged through the side gas outlet 8.

[0027] The above is only an embodiment of the present application, and does not limit the patent range of the present application, and any equivalent structure or equivalent process transformation using the content of the present application specification and drawings, or direct or indirect application in other related technical fields, are also included in the patent protection range of the present application.

Claims

1. A hollow fibre membrane module for air nitrogen enrichment characterised in that: The gas flow distributor (9) is in a columnar shape and the membrane shell (3) is in a hollow structure; two ends of the gas flow distributor (9) respectively pass out of the membrane shell (3) and are respectively open to form a main gas inlet (2) and a gas outlet; the side wall of the gas flow distributor (9) is uniformly distributed with a plurality of gas distribution holes (4) along the axial direction; the inner side of the membrane shell (3) is raised towards the gas flow distributor (9) to form a thread-shaped gas flow baffle (6), and a plurality of parallel fiber membrane filaments (5) are arranged in the cavity between the membrane shell (3) and the gas flow distributor (9).

2. A hollow fibre membrane module for air nitorgen enrichment as claimed in claim 1 characterised in that: The side wall of the membrane shell (3) is further provided with a side gas inlet (7) and a side gas outlet (8), and the side gas inlet (7) and the side gas outlet (8) are respectively located at the two end portions of the membrane shell (3).

3. A hollow fibre membrane module for air nitorgen enrichment as claimed in claim 2, characterised in that: The fiber membrane filaments (5) are arranged in parallel with the gas flow distributor (9), the fiber membrane filaments (5) are in a hollow structure, and the two ends of the fiber membrane filaments (5) are cast and fixed in the membrane shell (3) through an epoxy resin sealing layer (10), and the thickness of the epoxy resin sealing layer (10) is 3-5 mm.

4. A hollow fibre membrane module for air nitorgen enrichment as claimed in claim 3 wherein: The distance between the raised portion of the gas flow baffle (6) and the fiber membrane filament (5) closest to the outermost side of the gas flow baffle (6) is 2 times the outer diameter of the fiber.

5. A hollow fibre membrane module for air nitorgen enrichment as claimed in claim 4 wherein: The gas distribution hole (4) is a tapered diffusion hole.

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