Gas separation membrane module

Abstract

The invention belongs to the technical field of gas separation, and particularly discloses a gas separation membrane module. The module comprises a shell assembly, a plurality of gas inlet joints, a trapped gas outlet pipe and a permeated gas outlet pipe, the shell assembly is a cylindrical hollow shell, the interior of the shell assembly is divided into at least three independent channels in the axial direction, and a plurality of turbulent flow protrusions are arranged on the inner wall of each channel. Inclined air inlet holes which are in one-to-one correspondence with the channels and are connected and communicated with the air inlet joint are formed in one end of the side wall of the shell; the other end of the side wall is provided with a trapped gas outlet hole which is correspondingly connected and communicated with the trapped gas outlet pipe; a permeable gas gathering hole is formed in the head of one end of the shell and is communicated with a permeable gas outlet pipe. The module adopts a cross-flow multi-channel shell, is reasonable in structural design, can realize uniform distribution of airflow, remarkably reduces airflow dead zones among membrane filament bundles, and improves the effective utilization rate and mass transfer efficiency of membrane filaments. The device is suitable for various efficient and stable gas separation scenes such as industrial gas separation, natural gas purification, fuel cell tail gas treatment, chemical tail gas recovery and biogas purification.

Description

Technical Field

[0001] This invention relates to the field of gas separation technology, and more specifically, to a gas separation membrane module. Background Technology

[0002] Gas separation membrane technology, as a highly efficient, energy-saving, and environmentally friendly gas separation method, has become one of the core technologies in the field of modern industrial gas separation due to its advantages such as simple operation, small equipment footprint, and low energy consumption. As the core execution component of this technology, the structural design and performance of the gas separation membrane module directly determine the separation efficiency, operational stability, maintenance costs, and service life of the entire gas separation system.

[0003] Currently, most gas separation membrane modules used in industry adopt traditional single-channel or simple multi-channel shell designs, which have many technical defects in practical applications. The first is the prominent problem of airflow dead zones: due to the unreasonable distribution design of the inlet / outlet ports, the airflow cannot flow evenly across the surface of the membrane bundles after entering the module. Large areas of airflow dead zones are easily formed between the membrane bundles. The gas in the dead zone is in a stagnant state, which not only prevents the membrane fibers in that area from participating in the gas separation process, greatly reducing the effective utilization rate of the membrane fibers and the overall mass transfer efficiency, but also causes local contamination and accelerated aging of the membrane fibers due to the deposition of impurities in the stagnant gas on the surface of the membrane fibers, further shortening the service life of the membrane fibers.

[0004] Secondly, poor sealing performance can easily lead to gas cross-flow: the end cap sealing structure of existing membrane modules generally adopts a single rubber material or a single hard seal. Under long-term high pressure and high temperature industrial conditions, single rubber seals are prone to aging, wear, and deformation, resulting in poor sealing surface fit; while single hard seals are difficult to adapt to slight vibrations and shell deformation during module operation, easily creating sealing gaps. Both of these situations can lead to cross-flow between raw gas and permeate gas and trapped gas. Cross-flow not only seriously damages the gas separation effect, making the purity of the separated gas unable to meet industrial requirements, but may also cause safety hazards due to the mixing of different gases, and may even lead to premature scrapping of the membrane module.

[0005] In addition, the continuous stable operation time of existing membrane modules is usually no more than 12 months. Due to the accelerated aging of membrane fibers caused by airflow dead zones and the gas cross-flow caused by the decline in sealing performance, staff need to frequently stop the machine to maintain and replace the membrane modules. This not only significantly increases the operation and maintenance cost of industrial gas separation systems, but also causes production interruptions due to downtime, resulting in huge production losses.

[0006] To address the aforementioned issues, those skilled in the art have attempted to make localized improvements to the membrane module, such as adjusting the position of the inlet / outlet ports or changing the material of the seals. However, such improvements are mostly simple localized optimizations that do not fundamentally solve the problems of unreasonable airflow distribution and defects in the sealing structure design. The improvement effects are limited and still cannot meet the industrial production requirements for efficient, stable, and long-cycle operation of gas separation membrane modules.

[0007] Therefore, developing a gas separation membrane module that can completely reduce airflow dead zones, improve sealing performance, eliminate gas cross-flow, and extend operating cycles has become a key technical problem that urgently needs to be solved in the current gas separation technology field. Summary of the Invention

[0008] The present invention aims to provide a gas separation membrane module with a cross-flow multi-channel shell. Its ingenious structural design enables uniform airflow distribution, significantly reducing dead zones between membrane fibers and improving fiber utilization and mass transfer efficiency. Simultaneously, it achieves a double sealing effect, completely eliminating the risk of gas cross-flow. Ultimately, this significantly extends the continuous and stable operating time of the membrane module, reducing module replacement and maintenance frequency, and substantially lowering the operation and maintenance costs and downtime losses of industrial gas separation systems. It is applicable to various industrial scenarios requiring efficient and stable gas separation, such as industrial gas separation, natural gas purification, fuel cell exhaust gas treatment, chemical exhaust gas recovery, and biogas purification.

[0009] To achieve the above objectives, the preferred solution adopted by the present invention is: A gas separation membrane module includes a housing assembly, multiple air inlet connectors, multiple intercepted gas outlet pipes, and a permeate gas outlet pipe. The housing assembly includes a cylindrical hollow shell, the interior of which is divided into at least three independent channels along its axial direction. Each channel has multiple turbulence protrusions on its inner wall. One end of the side wall of the shell along its length has an inclined air inlet hole that corresponds to and communicates with each channel. The air inlet hole is connected to and communicates with the air inlet connector. The other end of the side wall of the shell along its length has an intercepted gas outlet hole that corresponds to and communicates with each channel. The intercepted gas outlet hole is connected to and communicates with the intercepted gas outlet pipe. One end of the shell has a permeate gas collection hole that is connected to and communicates with the permeate gas outlet pipe.

[0010] Furthermore, in a preferred embodiment of the present invention, the turbulence protrusions are semi-circular and uniformly distributed along the length of the inner wall of the channel, and the ratio of the spacing between adjacent turbulence protrusions to the diameter of the turbulence protrusions is 5-8:1-2.

[0011] Furthermore, in a preferred embodiment of the invention, the channel has a fan-shaped cross-section along the axis perpendicular to the housing. Furthermore, in a preferred embodiment of the present invention, the axis of the air inlet is at an angle of 30-45° to the axis of the outer casing.

[0012] Furthermore, in a preferred embodiment of the present invention, the diameter of the intercepted gas outlet hole is the same as the diameter of the inlet hole, and the ratio of the diameter of the permeate gas collection hole to the diameter of the inlet hole is 15-20:8-12.

[0013] Furthermore, in a preferred embodiment of the present invention, it further includes multiple sets of membrane fiber bundles; each set of membrane fiber bundles is correspondingly disposed in each channel, and the gap between the membrane fiber bundle and the inner wall of the channel is 2-3 mm.

[0014] Furthermore, in a preferred embodiment of the present invention, the membrane bundle is composed of multiple PEBA hollow fiber membrane filaments, the ratio of the outer diameter to the inner diameter of the PEBA hollow fiber membrane filaments is 1.75-1.85:0.8-1.0, the number of membrane filaments in each bundle is 100-150, and the filling density of each bundle is 10000-12000 m² / m³.

[0015] Furthermore, in a preferred embodiment of the present invention, an end cap assembly is also included; the end cap assembly includes cover plates respectively disposed and capable of covering both ends of the housing; the center of the cover plate is provided with a through hole that matches the permeate gas collection hole.

[0016] Furthermore, in a preferred embodiment of the present invention, the inner side of the cover plate is provided with an inner groove and an outer groove, which are coaxially distributed and spaced 3-5 mm apart; a nitrile rubber sealing ring is embedded in the inner groove; a polytetrafluoroethylene sealing ring is embedded in the outer groove, and the thickness ratio of the nitrile rubber sealing ring to the polytetrafluoroethylene sealing ring is 5-8:5-8.

[0017] Furthermore, in a preferred embodiment of the present invention, the ratio of the inner diameter, length and wall thickness of the shell is 80-120:500-800:5-8.

[0018] The beneficial effects of the gas separation membrane module provided by this invention are: The gas separation membrane module provided by this invention includes a housing assembly, multiple air inlet connectors, multiple intercepted gas outlet pipes, and a permeate gas outlet pipe. Based on the structural design of each of the housing assembly, the multiple air inlet connectors, the multiple intercepted gas outlet pipes, and the permeate gas outlet pipes, as well as the design of their interconnections, the resulting gas separation membrane module can achieve: (1) This invention adopts a cross-flow multi-channel shell structure, which uniformly divides the interior of the shell into at least three fan-shaped cross-flow channels. The air inlet corresponds to the cross-flow channel and is inclined, which can realize the uniform distribution and cross-flow entry of the raw gas, and avoid the concentrated airflow impacting the local membrane fiber bundles. At the same time, the turbulence protrusions set on the inner wall of the cross-flow channel can effectively turbulentize the airflow, making the airflow turbulent and fully contacting the membrane fiber bundles. Compared with the prior art, this invention combines the cross-flow multi-channel structure, the inclined air inlet, and the turbulence protrusions on the inner wall of the channel for the first time, optimizing the airflow distribution from the source of the airflow path and solving the problem of airflow dead zone. The above design fundamentally optimizes the airflow distribution and greatly reduces the airflow dead zone between the membrane fiber bundles; the effective utilization rate of the membrane fibers is significantly improved, and the gas separation efficiency of the entire membrane module is greatly improved.

[0019] Meanwhile, the separate channel arrangement of membrane fiber bundles facilitates the maintenance and replacement of individual channels, reducing maintenance difficulty and further lowering operation and maintenance costs compared to the overall replacement method of existing technologies.

[0020] (2) It can adapt to complex working conditions in various industrial scenarios such as industrial gas separation, natural gas purification, fuel cell tail gas treatment, chemical tail gas recovery, and biogas purification, such as corrosive gas environment, high pressure working conditions, and slight vibration environment; at the same time, the membrane module of the present invention can adjust the inner diameter, length, number of cross-flow channels, and the number of membrane fibers and filling density of the membrane fiber bundle according to different industrial needs, so as to achieve personalized customization and adapt to different gas separation needs, which is extremely practical. Attached Figure Description

[0021] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the structure of a gas separation membrane module provided in an embodiment of the present invention; Figure 2 A cross-sectional schematic diagram of a gas separation membrane module provided in an embodiment of the present invention; Figure 3 A longitudinal cross-sectional schematic diagram of the gas separation membrane module provided in an embodiment of the present invention; Icons: 10-Gas separation membrane module, 200-Shell assembly, 300-Membrane fiber bundle, 400-End cap assembly, 500-Inlet connector, 600-Retained gas outlet pipe, 700-Permeable gas outlet pipe, 210-Shell, 220-Channel, 230-Separator, 240-Turbulence protrusion, 250-Inlet port, 260-Retained gas outlet port, 270-Permeable gas collection port, 280-Pouring layer, 290-Stainless steel fixing mesh, 410-Cover plate, 411-Through hole, 412-Inner groove, 413-Outer groove. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0024] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0025] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0026] Example 1 The following is in conjunction with the appendix Figure 1-3 The present invention will be further described as follows: This embodiment provides a gas separation membrane module 10. Please refer to [link / reference]. Figure 1-3 The gas separation membrane module 10 includes a housing assembly 200, multiple sets of membrane fiber bundles 300, an end cap assembly 400, multiple air inlet connectors 500, multiple intercepted gas outlet pipes 600, and a permeate gas outlet pipe 700.

[0027] The inlet connector 500, the permeate gas outlet pipe 700, and the interception gas outlet pipe 600 are all gas delivery channels 220. They are all made of 316L stainless steel, which has excellent corrosion resistance and mechanical strength, ensuring the service life and operational stability of the connecting parts, while avoiding electrochemical reactions between different materials and preventing component corrosion.

[0028] The outer shell assembly 200 serves as the support for the entire gas separation membrane module 10 and the foundation for the airflow channels 220, employing a cross-flow multi-channel structure. The outer shell assembly 200 includes a cylindrical hollow shell 210 made of 316L stainless steel. 316L stainless steel possesses excellent corrosion resistance, high-temperature resistance, and mechanical strength, enabling it to adapt to complex operating conditions in industrial gas separation scenarios, such as corrosive gas environments and high-pressure working conditions, while effectively ensuring the structural stability and service life of the outer shell assembly 200.

[0029] In this embodiment, the ratio of the inner diameter, length, and wall thickness of the housing 210 is 80-120:500-800:5-8, preferably 110:600:6. This size design ensures that the housing assembly 200 has sufficient pressure-bearing capacity to stably withstand working pressures up to 0.6MPa, while also taking into account the overall volume of the gas separation membrane module 10, making it suitable for installation space in industrial settings.

[0030] The interior of the housing 210 is divided into at least three independent cross-flow channels 220 along its axial direction, preferably six. Each cross-flow channel 220 has a fan-shaped cross section along the axis perpendicular to the housing 210, and the central angles of the fan are equal, ensuring that the airflow area of ​​each channel 220 is consistent and achieving uniform airflow distribution.

[0031] A partition 230 is provided between adjacent crossflow channels 220. The partition 230 has a thickness of 2-3 mm, preferably 2 mm, and is integrally formed with the housing 210. The integral forming design can not only effectively enhance the overall rigidity of the housing assembly 200 and prevent the housing 210 from deforming under high pressure conditions, but also avoid gaps between the partition 230 and the housing 210, prevent airflow from flowing between channels 220, and ensure the independence of each crossflow channel 220.

[0032] In this embodiment, the inner wall of each crossflow channel 220 is provided with a few turbulent flow protrusions 240. In this embodiment, the turbulent flow protrusions 240 are semi-circular and are evenly distributed along the length of the inner wall of the channel 220. The ratio of the spacing between adjacent turbulent flow protrusions 240 to the diameter of the turbulent flow protrusions 240 is 5-8:1-2, preferably 6:2.

[0033] The turbulence protrusion 240 can disturb the airflow flowing through the channel 220, break the smooth flow state of the airflow along the wall of the channel 220, and make the airflow turbulent. This allows the airflow to contact the surface of the membrane bundle 300 more fully, avoids the airflow from stagnating between the membrane bundles 300, further reduces the dead zone of the airflow, and improves the mass transfer efficiency.

[0034] In this embodiment, one end of the sidewall of the housing 210 along its length is provided with an inclined air inlet 250, which corresponds to and communicates with the channels 220. The air inlet 250 is connected to and communicates with the air inlet connector 500. The air inlets 250 are evenly distributed along the circumference of the housing, and the number of air inlets 250 corresponds to the number of cross-flow channels 220, ensuring that each cross-flow channel 220 can independently receive air. The diameter of the air inlet 250 is 8-12 mm, preferably 10 mm; the axis of the air inlet 250 forms an angle of 30-45° with the axis of the housing assembly 200, preferably 40°. The inclined air inlets 250 allow the raw material gas to enter each cross-flow channel 220 in a cross-flow manner. On the one hand, this avoids damage to the membrane fibers caused by the vertical impact of the airflow, protecting the structural integrity of the membrane fibers; on the other hand, it guides the airflow to flow along the axial direction of the membrane fiber bundle 300, increasing the contact time and contact area between the airflow and the membrane fibers, ensuring that the airflow is evenly distributed on the surface of the membrane fibers.

[0035] The air inlet connector 500 corresponds one-to-one with the air inlet port 250 and can be connected to the housing 210 by a threaded connection. Threaded connections offer advantages such as tight connection and easy assembly / disassembly, facilitating membrane module installation and maintenance. The inner diameter of the air inlet connector 500 is matched to the diameter of the air inlet port 250, ranging from 8-12 mm, preferably 10 mm, ensuring that the raw material gas can smoothly pass through the air inlet connector 500 into the cross-flow channel 220 without flow resistance. A sealing thread is provided on the outer side of the air inlet connector 500 for the raw material gas delivery. When connected to a pipeline, this further ensures a tight seal, preventing raw material gas leakage at the connector.

[0036] At the other end of the side wall of the housing 210 along its length, there are intercepted gas outlet holes 260 that correspond one-to-one with and communicate with the channels 220. The intercepted gas outlet holes 260 are connected to and communicate with the intercepted gas outlet pipe 600. The intercepted gas outlet holes 260 and the air inlet holes 250 are symmetrically distributed. The diameter of the intercepted gas outlet holes 260 is the same as that of the air inlet holes 250, which is 8-12 mm, preferably 10 mm. It is used to discharge the intercepted gas that has not passed through the membrane wall after separation by the membrane fibers. The symmetrical distribution design can ensure the smooth discharge of the intercepted gas and avoid the intercepted gas from stagnating in the channels 220, thus ensuring the flow of air.

[0037] The intercepted gas outlet pipe 600 corresponds one-to-one with the intercepted gas outlet hole 260, and is connected to the housing 210 by the same threaded connection. The inner diameter of the intercepted gas outlet pipe 600 is matched with the diameter of the intercepted gas outlet hole 260, which is 8-12mm, preferably 10mm, to ensure that the intercepted gas after separation can be discharged smoothly, avoid the intercepted gas from being stuck in the channel 220, and ensure the flow of air.

[0038] One end of the housing 210 has a permeate collection hole 270 that connects to and communicates with the permeate outlet pipe 700. The diameter of the permeate collection hole 270 is 15-20 mm, preferably 12 mm, and it is used to collect the permeate separated from the membrane fiber bundles 300 in each crossflow channel 220 and discharge it uniformly through the permeate outlet pipe 700. The central collection design can achieve efficient collection of permeate and reduce the retention loss of permeate.

[0039] The permeate outlet pipe 700 is connected to the permeate collection hole 270 by a threaded connection. The inner diameter of the permeate outlet pipe 700 is 15-20mm, preferably 18mm, which is consistent with the diameter of the permeate collection hole 270. This ensures that the permeate collected by each crossflow channel 220 can be efficiently and smoothly discharged to the subsequent processing unit, reducing the retention loss of permeate.

[0040] The membrane fiber bundle 300 is the core functional component for gas separation. In this embodiment, each group of membrane fiber bundles 300 is correspondingly arranged in each cross-flow channel 220. This arrangement in separate channels 220 not only ensures the independent operation of each membrane fiber bundle 300 and avoids mutual interference between them, but also facilitates subsequent single-channel 220 maintenance and membrane fiber replacement, reducing maintenance difficulty and cost. The gap between the membrane fiber bundle 300 and the inner wall of the channel 220 is 2-3 mm, preferably 3 mm, to ensure smooth airflow around the membrane fiber bundle 300, while preventing the membrane fiber bundle 300 from shifting under airflow impact or colliding with the inner wall of the channel 220 and causing damage.

[0041] The membrane bundle 300 uses hollow fiber membrane fibers made of polyamide block copolymer and flexible polyether block copolymer (PEBA). PEBA combines the high strength and high wear resistance of polyamide with the high flexibility and high gas permeability of polyether, exhibiting excellent gas selectivity and mechanical stability. It can ensure efficient gas separation while adapting to airflow impact and slight vibration under industrial conditions, and is not prone to problems such as membrane fiber breakage or damage.

[0042] In this embodiment, the ratio of the outer diameter to the inner diameter of the PEBA hollow fiber membrane filament is 1.75-1.85:0.8-1.0, preferably 1.8:0.9. This size design can maximize the specific surface area of ​​the membrane filament while ensuring the mechanical strength of the membrane filament, thereby improving the gas separation efficiency. The length of the membrane filament is adapted to the length of the shell 210, which is 500-800mm, preferably 600mm, to ensure that the membrane filament can be fully filled in the cross-flow channel 220, thereby improving the effective utilization rate of the membrane filament.

[0043] In this embodiment, each membrane fiber bundle 300 contains 100-150 membrane fibers, preferably 120, and the packing density of the membrane fiber bundle 300 is 10000-12000 m² / m³, preferably 11000 m² / m³. Under the above-mentioned design of the number of membrane fibers and packing density in this embodiment, the effective separation area per unit volume can be guaranteed, improving the overall separation efficiency, while avoiding airflow obstruction due to excessively dense membrane fibers, thus preventing the formation of new airflow dead zones.

[0044] In this embodiment, the two ends of the membrane fiber bundle 300 are fixed by epoxy resin potting. The thickness of the epoxy resin potting layer 280 is 5-8 mm, preferably 6 mm. During the potting process, the potting layer 280 and the membrane fiber are seamlessly bonded. On the one hand, this fixes the membrane fiber bundle 300 into a whole, preventing the membrane fiber from becoming scattered or entangled under the impact of airflow, thus ensuring the structural stability of the membrane fiber bundle 300. On the other hand, it effectively seals the gap between the membrane fiber and the potting layer 280, preventing gas from leaking through the gap and ensuring the effectiveness of gas separation. A stainless steel fixing mesh 290 is provided on the outside of the potting layer 280. The mesh size of the fixing mesh is 20-30 mesh, preferably 25 mesh. The stainless steel fixing mesh 290 can further fix the membrane fiber bundle 300, enhance the impact resistance of the membrane fiber bundle 300, and the 20-30 mesh design does not obstruct the flow of airflow and does not affect the contact between the gas and the membrane fiber bundle 300.

[0045] In this embodiment, the end cap assembly 400 includes cover plates 410 respectively disposed and capable of covering both ends of the housing 210. The main body of the end cap is a circular cover plate 410, made of 316L stainless steel. The diameter of the circular cover plate 410 is 5-10 mm larger than the outer diameter of the housing assembly 200, preferably 8 mm, to ensure that the cover plate 410 can completely cover the end of the housing assembly 200, achieving a complete seal. The center of the cover plate 410 is provided with a through hole 411 that matches the permeable gas collection hole 270 at the bottom of the housing 210. The diameter of the through hole 411 is 15-20 mm, preferably 18 mm, for the flow of permeable gas, ensuring that the permeable gas in each crossflow channel 220 can smoothly pass through the end cap through hole 411 to converge to the permeable gas collection hole 270, and then be discharged by the permeable gas outlet pipe 700.

[0046] The inner side of the cover plate 410, that is, the side that fits against the end head of the housing 210, is provided with an annular groove (not marked in the figure). The annular groove includes an inner groove 412 and an outer groove 413. The inner groove 412 and the outer groove 413 are coaxially arranged, and the distance between them is 3-5mm, preferably 4mm. The design of the double groove provides an installation basis for the double sealing structure and realizes the spatial layout of double sealing.

[0047] The inner groove 412 contains a nitrile rubber sealing ring with a Shore hardness of 70-80 HA and a thickness of 5-8 mm, preferably 6 mm. The outer groove 413 contains a polytetrafluoroethylene (PTFE) sealing ring with an elastic modulus of 1000-1200 MPa and a thickness of 5-8 mm, preferably 6 mm.

[0048] The nitrile rubber sealing ring and the polytetrafluoroethylene (PTFE) sealing ring work together. The nitrile rubber sealing ring mainly provides elastic preload to ensure a tight fit between the sealing surfaces and solve the problem of sealing gaps. The PTFE sealing ring mainly provides wear-resistant and corrosion-resistant protection, extending the service life of the sealing structure. The two complement each other to achieve a sealing effect of 1 + 1 > 2.

[0049] The cover plate 410 and the housing 210 can be fixedly connected by bolts, and are evenly distributed along the circumference of the cover plate 410.

[0050] The gas separation membrane module 10 of the present invention has a simple assembly process and can be assembled in batches using existing industrial equipment. The specific assembly steps are as follows: (1) Installation of membrane fiber bundle 300: The prepared membrane fiber bundle 300 is installed into each cross-flow channel 220. The position of the membrane fiber bundle 300 is adjusted to ensure that the gap between the membrane fiber bundle 300 and the inner wall of the channel 220 is uniform. The gap is controlled to be 2-3 mm, preferably 3 mm, to ensure that each membrane fiber bundle 300 is in the center of the channel 220 and to avoid contact with the inner wall of the channel 220.

[0051] (2) Potting and fixing: After the position of the membrane fiber bundle 300 is adjusted, epoxy resin is used to pot the two ends of the membrane fiber bundle 300. During the potting process, ensure that the epoxy resin fully fills the gap between the membrane fibers and fits seamlessly with the membrane fibers. The thickness of the potting layer 280 is controlled to be 5-8mm, preferably 6mm. After the epoxy resin is cured, the stainless steel fixing mesh 290 is fixed on the outside of the potting layer 280 to complete the fixing of the membrane fiber bundle 300.

[0052] (3) End cap installation: Install the two cover plates 410 at both ends of the housing 210 respectively, adjust the position of the cover plates 410 to ensure that the nitrile rubber sealing ring and polytetrafluoroethylene sealing ring on the inner side of the cover plate 410 are tightly fitted with the end head of the housing 210 and the groove of the end cap without gap; then arrange the bolts evenly along the circumference of the cover plate 410, and tighten the bolts with a torque wrench to complete the fixed connection between the cover plate 410 and the housing 210.

[0053] (4) Installation of connecting components: Connect the air inlet connector 500 and the gas interception outlet pipe 600 to the air inlet hole 250 and the gas interception outlet hole 260 on the side wall of the housing 210 respectively by threading. Connect the permeate outlet pipe 700 to the permeate gas collection hole 270 at the end of the housing 210 by threading. During the connection process, ensure that the threads are tightened to ensure the sealing effect of the connection and prevent gas leakage. At this point, the assembly of the entire gas separation membrane module 10 is completed.

[0054] The specific working process of the gas separation membrane module 10 of the present invention is as follows: The raw gas is transported to the inlet connector 500 through the raw gas conveying pipeline, and enters the cross-flow channels 220 of the housing 210 in an inclined cross-flow manner through the inlet connector 500. Since the inlet holes 250 correspond one-to-one with the cross-flow channels 220, and the flow area of ​​each cross-flow channel 220 is consistent, the raw gas can be evenly distributed into each cross-flow channel 220. The raw gas entering the cross-flow channel 220 is disturbed by the turbulence protrusions 240 on the inner wall of the channel 220, breaking the stable flow state and forming turbulence. It flows evenly along the axial direction of the membrane fiber bundle 300 and makes full contact with the membrane fiber bundle 300, which greatly reduces the airflow dead zone between the membrane fiber bundles 300 and improves the effective utilization rate of the membrane fibers.

[0055] After the feed gas comes into contact with the surface of the PEBA hollow fiber membrane, the target permeate component in the feed gas, under the selective permeation of the membrane, permeates through the membrane wall of the hollow fiber membrane according to the dissolution-diffusion mechanism and enters the inner cavity of the membrane, forming permeate gas. Meanwhile, the components in the feed gas that cannot permeate through the membrane wall become trapped gas and continue to flow along the cross-flow channel 220. Finally, they enter the trapped gas outlet pipe 600 through the trapped gas outlet hole 260 and are led out to the subsequent trapped gas collection or treatment unit.

[0056] Under the influence of concentration and pressure differences, the permeate gas in the inner cavity of each cross-flow channel 220 flows towards the end of the membrane fiber bundle 300. It then converges through the through hole 411 in the center of the cover plate 410 to the permeate gas collection hole 270 at the end of the housing 210. From there, it enters the permeate gas outlet pipe 700 and is then led out to the subsequent permeate gas purification or utilization unit, thus completing the entire gas separation process.

[0057] Throughout the operation of the membrane module, the nitrile rubber sealing ring and the polytetrafluoroethylene (PTFE) sealing ring of the end cap assembly 400 maintain a good sealing condition. Under the action of pre-tightening force, the nitrile rubber sealing ring fits tightly against the sealing surface, and the PTFE sealing ring provides wear-resistant protection. The two work together to effectively prevent cross-flow between feed gas, permeate gas, and retained gas, ensuring the gas separation effect. At the same time, the design of the cross-flow channel 220 and the inclined air inlet 250 ensures that the airflow is in full contact with the membrane fiber bundle 300, improves the mass transfer efficiency, reduces the deposition of impurities on the surface of the membrane fibers, slows down the aging rate of the membrane fibers, and extends the service life of the membrane fibers.

[0058] The assembly steps of the gas separation membrane module 10 in this embodiment are carried out according to the assembly relationship described in the technical solution of the present invention. After the assembly is completed, it is applied to the industrial mixed gas separation scenario. The raw material to be separated is chemical industrial mixed gas (containing N2, O2, CO2 and other components), with a working pressure of 0.6MPa and a working temperature of 35℃.

[0059] Comparative Test To further verify the technical effectiveness of the gas separation membrane module of the present invention, a comparative test was conducted between the gas separation membrane module provided in Example 1 of the present invention and an existing conventional gas separation membrane module (Tianbang Membrane Technology TBM™ G-40). The test conditions were kept consistent, namely, the raw gas composition, working pressure, working temperature, and gas flow rate were all the same. The test items included the proportion of dead zone in the gas flow, mass transfer efficiency, and gas cross-flow rate. The test results are shown in Table 1 below: (1) Percentage of dead zones in airflow (%): The membrane fiber bundles are removed from the inside of the membrane module, while the outer shell, inlet / outlet vents and end cap sealing structure are retained to simulate the airflow channel in actual operation. Dry air is introduced at the module's rated working pressure (0.4-0.6MPa), and atomized tracer is added at the air inlet. The movement trajectory of the airflow inside the module is captured by a high-speed camera, marking eddies, stagnation, and areas without airflow. A laser Doppler velocimeter was used to arrange measuring points in a 5mm×5mm×5mm grid inside the module. The airflow velocity was measured point by point, and the location of the dead zone measuring point with a velocity ≤0.05m / s was recorded. The volume of the dead zone is reconstructed using 3D modeling software, and the percentage of the dead zone volume to the effective chamber volume of the module is calculated, which is the airflow dead zone ratio. Parallel testing: The same module is tested three times, and the average value is taken. The test error is controlled within ±0.5%.

[0060] (2) Mass transfer efficiency (%): Tested in accordance with the relevant standard GB / T 1038-2022 "Test method for gas permeability of plastic films and sheets - differential pressure method"; (3) Gas flow rate (%): Tested in accordance with the relevant standard GB / T 15171-2022 "Test Method for Sealing Performance of Flexible Packaging".

[0061] Table 1 As can be seen from the above comparative test results, the gas separation membrane module provided by the present invention is significantly superior to the existing traditional module in all performance indicators. It can effectively solve the technical defects of the existing module, such as large airflow dead zone, poor sealing performance, and easy gas crossflow, and has significant technical advantages and economic benefits.

[0062] In summary, the gas separation membrane module provided in this embodiment features a cross-flow multi-channel shell with an ingenious structural design. This design enables uniform airflow distribution, significantly reducing dead zones between membrane fibers and improving the effective utilization rate and mass transfer efficiency of the membrane fibers. Simultaneously, it achieves a double sealing effect, completely eliminating the risk of gas cross-flow. Ultimately, this significantly extends the continuous and stable operating time of the membrane module, reducing the frequency of module replacement and maintenance, and substantially lowering the operation and maintenance costs and downtime losses of industrial gas separation systems. It is applicable to various industrial scenarios requiring efficient and stable gas separation, such as industrial gas separation, natural gas purification, fuel cell exhaust gas treatment, chemical exhaust gas recovery, and biogas purification.

[0063] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A gas separation membrane module, characterized in that, Includes housing assembly, multiple air inlet connectors, multiple intercepted gas outlet pipes and permeable gas outlet pipes; The outer casing assembly includes a cylindrical hollow shell, the interior of which is divided into at least three independent channels along its axial direction. Each channel has multiple turbulence protrusions on its inner wall. One end of the side wall of the shell along its length has an inclined air inlet corresponding to and communicating with each of the channels. The air inlet is connected to and communicates with the air inlet connector. The other end of the side wall of the shell along its length has a trapping gas outlet corresponding to and communicating with each of the channels. The trapping gas outlet is connected to and communicates with the trapping gas outlet pipe. One end of the shell has a permeable gas collection hole connected to and communicates with the permeable gas outlet pipe.

2. The gas separation membrane module according to claim 1, characterized in that, The turbulence protrusions are semi-circular and evenly distributed along the length of the inner wall of the channel. The ratio of the spacing between adjacent turbulence protrusions to the diameter of the turbulence protrusion is 5-8:1-2.

3. The gas separation membrane module according to claim 1, characterized in that, The channel is fan-shaped along a cross section perpendicular to the axis of the housing.

4. The gas separation membrane module according to claim 1, characterized in that, The centerline of the air inlet forms an angle of 30-45° with the centerline of the outer casing.

5. The gas separation membrane module according to claim 1, characterized in that, The diameter of the intercepted gas outlet is the same as the diameter of the inlet, and the ratio of the diameter of the permeable gas collection hole to the diameter of the inlet is 15-20:8-12.

6. The gas separation membrane module according to claim 1, characterized in that, It also includes multiple sets of membrane fiber bundles; each set of membrane fiber bundles is correspondingly arranged in each of the channels, and the gap between the membrane fiber bundle and the inner wall of the channel is 2-3 mm.

7. The gas separation membrane module according to claim 6, characterized in that, The membrane bundle is composed of multiple PEBA hollow fiber membrane filaments. The ratio of the outer diameter to the inner diameter of the PEBA hollow fiber membrane filaments is 1.75-1.85:0.8-1.

0. Each membrane bundle contains 100-150 membrane filaments and the filling density of each membrane bundle is 10000-12000 m² / m³.

8. The gas separation membrane module according to claim 1, characterized in that, It also includes an end cap assembly; the end cap assembly includes cover plates respectively provided and capable of covering both ends of the housing; the center of the cover plate is provided with a through hole that matches the permeate gas collection hole.

9. The gas separation membrane module according to claim 1, characterized in that, The cover plate has an inner groove and an outer groove on its inner side, which are coaxially distributed and spaced 3-5 mm apart; a nitrile rubber sealing ring is embedded in the inner groove; a polytetrafluoroethylene sealing ring is embedded in the outer groove, and the thickness ratio of the nitrile rubber sealing ring to the polytetrafluoroethylene sealing ring is 5-8:5-8.

10. The gas separation membrane module according to claim 1, characterized in that, The ratio of the inner diameter, length, and wall thickness of the shell is 80-120:500-800:5-8.

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