Gas separation membrane module

Abstract

The present disclosure relates to a gas separation membrane assembly, which comprises at least one separation unit, the separation unit comprising a membrane sheet, an inlet gas net and a product gas flow channel assembly, the membrane sheet having opposite inlet gas side and product gas side, the inlet gas net being attached to the inlet gas side, the product gas flow channel assembly being attached to the product gas side and forming a sealed structure with the product gas side, the product gas flow channel assembly comprising a flow guide cloth and at least one layer of flow guide net arranged in a stack. The gas separation membrane assembly of the present disclosure can significantly improve the gas separation efficiency, reduce the gas flow resistance and concentration polarization effect on the product gas side, meet the requirements of high flux membrane on the assembly, effectively exert the separation performance of the membrane sheet, and be suitable for various industrial gas separation scenarios such as carbon dioxide, methane, ethanol and oxygen.

Description

Technical Field

[0001] This disclosure relates to a gas separation membrane assembly. Background Technology

[0002] Membrane separation technology has been widely used in industry due to its advantages such as simple process, low operating cost, small footprint, weak scale-up effect, and modular design. In liquid separation, membrane technology has been successfully applied to water treatment and wastewater treatment; in gas separation, gas separation membrane technology, with its advantages of requiring no chemical reagents and low energy consumption, is gradually being applied to high-purity gas preparation, pollutant gas removal, and carbon capture. As industry demands increasingly higher efficiency and cost-effectiveness in gas separation, the development of high-efficiency gas separation membrane modules has become an important direction for technological development.

[0003] Currently, the design of gas separation membrane modules largely draws on the structural forms of liquid separation membrane modules, including flat sheet membranes, hollow fiber membranes, and spiral wound membranes. Among these, spiral wound membrane modules have become the mainstream form for gas separation applications due to their compact structure, high packing density, and ease of installation and maintenance. However, the gas flow channel structure of these modules is still based on the design of traditional liquid separation membrane modules, failing to fully consider the special requirements of gas flow characteristics during gas separation. In high-flux applications, this can easily lead to problems such as high airflow resistance and turbulent flow, limiting the membrane's performance and resulting in a significantly lower gas selectivity and flux compared to the membrane itself, thus affecting the separation effect. Summary of the Invention

[0004] The purpose of this disclosure is to provide a gas separation membrane module with improved separation performance.

[0005] To achieve the above objectives, this disclosure provides a gas separation membrane assembly, which includes at least one separation unit. The separation unit includes a membrane, an inlet mesh, and a gas generation channel assembly. The membrane has an inlet side and a gas generation side facing each other. The inlet mesh is attached to the inlet side, and the gas generation channel assembly is attached to the gas generation side and forms a sealing structure with the gas generation side. The gas generation channel assembly includes a layered guide cloth and at least one layer of guide mesh.

[0006] Optionally, the thickness of the guide net is 0.1~2mm; and / or, the mesh area of ​​the guide net is 0.5~25mm². 2 .

[0007] Optionally, the material of the guide net includes at least one of polypropylene, polyester, polyamide, polyvinyl alcohol, polyacrylonitrile, polyvinyl chloride, protein fiber, and carbon fiber.

[0008] Optionally, the gas generation channel assembly includes a first guide net, a guide cloth, and a second guide net stacked in sequence. The first guide net, the guide cloth, and the second guide net are bonded together by a sealant or a pressing process, and the gas generation channel assembly is sealed and attached to the gas generation side.

[0009] Optionally, the thickness of the flow guiding cloth is 0.1~0.3mm.

[0010] Optionally, the material of the flow-guiding cloth includes at least one of polyester, polypropylene, polyamide, polyvinyl alcohol, polyacrylonitrile, polyvinyl chloride, protein fiber, and carbon fiber.

[0011] Optionally, the weaving density of the flow guiding fabric is 5~20 / cm in the transverse direction and 10~30 / cm in the longitudinal direction.

[0012] Optionally, the thickness of the air intake mesh is 0.1~2mm; and / or, the mesh area of ​​the air intake mesh is 0.5~25mm². 2 .

[0013] Optionally, the air intake mesh may be made of at least one of polyester, polypropylene, polyamide, polyvinyl alcohol, polyacrylonitrile, polyvinyl chloride, protein fiber, and carbon fiber.

[0014] Optionally, the gas separation membrane assembly further includes a gas collecting tube, the separation unit is wound around the surface of the gas collecting tube, and one end of the gas generating channel assembly is connected to the gas collecting tube.

[0015] The above technical solution uses a composite structure of flow guide cloth and flow guide net on the gas production side of the membrane to form a gas production channel component, which can significantly improve gas separation efficiency, reduce gas flow resistance and concentration polarization effect on the gas production side, meet the requirements of high-flux membranes for components, effectively exert the separation performance of the membrane, and is suitable for membrane separation scenarios of various industrial gases such as carbon dioxide, methane, ethanol, and oxygen.

[0016] Other features and advantages of this disclosure will be described in detail in the following detailed description section. Attached Figure Description

[0017] The accompanying drawings are provided to further illustrate the present disclosure and form part of the specification. They are used together with the following detailed description to explain the present disclosure, but do not constitute a limitation thereof. In the drawings: Figure 1 This is a cross-sectional structural schematic diagram of a gas separation membrane assembly according to a specific embodiment of the present disclosure.

[0018] Figure 2 yes Figure 1 A schematic diagram of the gas generation channel component in a gas separation membrane module.

[0019] Explanation of reference numerals in the attached figures 1—Airflow channel assembly, 1-1 airflow guide cloth, 1-2 airflow guide net, 2—diaphragm, 3—air inlet net, 4—sealant. Detailed Implementation

[0020] The specific embodiments of this disclosure will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit this disclosure.

[0021] This disclosure provides a gas separation membrane assembly, with reference to... Figure 1 and Figure 2 The gas separation membrane assembly includes at least one separation unit, which includes a membrane 2, an air inlet mesh 3, and a gas generation channel assembly 1. The membrane 2 has an air inlet side and a gas generation side, respectively. The air inlet mesh 3 is attached to the air inlet side, and the gas generation channel assembly 1 is attached to the gas generation side and forms a sealing structure with the gas generation side. The gas generation channel assembly 1 includes a layered guide cloth 1-1 and at least one layer of guide mesh 1-2.

[0022] This disclosure employs a composite structure of a guide cloth 1-1 and a guide net 1-2 on the gas-generating side of the diaphragm 2 to form a gas-generating channel assembly 1. On one hand, the guide cloth 1-1 supports and uniformly guides the gas flow, preventing turbulence and facilitating the flow of generated gas towards the central gas collecting pipe. On the other hand, the guide net 1-2 provides a smooth gas diffusion and flow path for the gas-generating surface of the diaphragm. Together, these two components reduce gas-generating airflow resistance and effectively prevent excessively high local concentrations or uneven flow during gas generation, thereby significantly reducing concentration polarization and improving the gas flux and selective separation performance of the membrane module. This design helps to fully utilize the separation capability of the diaphragm 2, enabling the membrane module's separation performance to approach or reach that of the diaphragm, effectively solving the problem of limited performance in existing gas separation membrane modules.

[0023] The flow guide net 1-2 has a mesh structure, and the shape of the mesh can be designed according to specific separation requirements, such as triangular, quadrilateral, pentagonal, hexagonal, or circular shapes. The mesh size of the flow guide net 1-2 directly affects the smoothness of gas diffusion and flow on the gas-generating side surface of the diaphragm. In one embodiment, the mesh area of ​​the flow guide net 1-2 can be 0.5~25mm². 2 For example, 0.5mm 2 1mm 2 2mm 2 5mm 2 8mm 2 10mm 2 15mm 2 20mm 2 25mm2 The preferred thickness is 2~15mm. 2 The mesh area refers to the opening area of ​​a single mesh hole.

[0024] The thickness of the flow guide net 1-2 can be adjusted within a certain range. When the thickness of the flow guide net 1-2 is within a suitable range, it is beneficial to further improve the separation effect while taking into account the stability of the component structure and the membrane packing density. In one specific embodiment, the thickness of the flow guide net 1-2 can be 0.1~2mm, such as 0.1mm, 0.2mm, 0.3mm, 0.5mm, 0.8mm, 1mm, 1.2mm, 1.5mm, 1.8mm, 2mm, etc., preferably 0.2~1mm. The length of the flow guide net 1-2 is determined according to the length of a single membrane sheet after folding (longer than the folded membrane sheet), specifically it can be 0.3~1.5m, such as 0.3m, 0.5m, 0.8m, 1m, 1.2m, 1.5m, etc. Here, thickness refers to... Figure 1 The dimension in the vertical direction (i.e., the Y-axis direction) refers to the dimension in the direction perpendicular to the paper (i.e., the plane containing the X and Y axes).

[0025] To achieve ideal gas separation efficiency, flow channel stability, and component reliability and durability, the flow guide net 1-2 can be made of organic materials. Specifically, the material of the flow guide net 1-2 may include at least one of polypropylene, polyester, polyamide, polyvinyl alcohol, polyacrylonitrile, polyvinyl chloride, protein fiber, and carbon fiber.

[0026] The number of layers in the flow guiding net 1-2 can be designed according to actual separation needs, for example, it can be 1 to 6 layers, preferably multiple layers, to form a stable gas flow channel. When the number of layers in the flow guiding net 1-2 is multiple, the grid shape and distribution of each layer of the flow guiding net 1-2 can be kept consistent to form a regular gas flow channel.

[0027] The gas guiding cloth 1-1 can be a woven gas guiding cloth, and the weaving method can be plain weave, twill weave, etc. Its thickness can be adjusted within a certain range, specifically 0.1~0.3mm, for example 0.1mm, 0.12mm, 0.15mm, 0.18mm, 0.2mm, 0.25mm, 0.3mm, etc., preferably 0.1~0.2mm. The length of the guiding cloth 1-1 is consistent with the length of the corresponding guiding net.

[0028] The diversion fabric 1-1 preferably has excellent air permeability and flexibility, and the weaving density can be 5~20 / cm in the transverse direction and 10~30 / cm in the longitudinal direction, preferably 7~15cm in the transverse direction and 10~15 / cm in the longitudinal direction.

[0029] The flow guiding cloth 1-1 can be made of organic materials. Specifically, the material of the flow guiding cloth 1-1 may include at least one of polypropylene, polyester, polyamide, polyvinyl alcohol, polyacrylonitrile, polyvinyl chloride, protein fiber, and carbon fiber, preferably at least one of polyester, polyamide, and polyvinyl alcohol.

[0030] The flow guide cloth 1-1 and the flow guide net 1-2 are bonded together using sealant or a pressing process, and further bonded to the gas-generating side of the diaphragm using sealant to form a sealed gas-generating channel, ensuring that the gas-generating channel is in operation. Figure 1 The left and right sides and the end away from the central gas collecting pipe are sealed on three sides. The flow path of the generated gas in the sealed membrane bag is effectively guided, and the gas flows generally towards the central gas collecting pipe, eliminating leakage and reducing turbulence in the direction of the non-central gas collecting pipe in the gas generation channel, thereby improving the operational stability and separation efficiency of the component. Specifically, the flow guide cloth 1-1 and the flow guide net 1-2 can be sealed by mechanical or chemical means. For example, the edges of the flow guide cloth 1-1 and the flow guide net 1-2 can be bonded with sealant 4 to form a closed edge sealing line; or, the flow guide cloth 1-1 and the flow guide net 1-2 can be bonded over a large area, and the edges can be sealed by a pressing process (such as hot pressing).

[0031] In one specific implementation, such as Figure 2 As shown, the gas flow channel assembly 1 may include a first flow guide net 1-2, a flow guide cloth 1-1, and a second flow guide net 1-2 stacked sequentially. The first flow guide net and / or the second flow guide net 1-2 are sealed and adhered to the gas-producing side of the diaphragm 2. The first flow guide net 1-2, the flow guide cloth 1-1, and the second flow guide net 1-2 are integrated by means of sealant or pressing. This embodiment is particularly suitable for structures in which multiple separation units are stacked. In this case, the first flow guide net 1-2 can be adhered to the gas-producing side of the diaphragm 2 in the previous separation unit, and the second flow guide net 1-2 can be adhered to the gas-producing side of the diaphragm 2 in the next separation unit, forming a consistent gas flow channel. Alternatively, this embodiment is also suitable for structures in which the diaphragm 2 is folded in half. In this case, two gas-producing sides are formed on the inner side of the folded diaphragm 2, and the first flow guide net 1-2 and the second flow guide net 1-2 are respectively adhered to one gas-producing side, forming a symmetrical gas flow channel structure.

[0032] The air intake grille 3 has a mesh structure, and the shape of the mesh is not particularly limited; for example, it can be triangular, quadrilateral, pentagonal, hexagonal, or circular. The mesh size of the air intake grille 3 can be adjusted within a wide range; specifically, the mesh area of ​​the air intake grille 3 can be 0.5~25mm. 2 Preferably 2~15mm 2 .

[0033] The thickness of the air intake mesh 3 can be adjusted within a certain range, specifically 0.1~2mm, such as 0.1mm, 0.2mm, 0.5mm, 0.8mm, 1mm, 1.2mm, 1.5mm, 1.8mm, 2mm, etc., preferably 0.2~1mm. The length of the air intake mesh 3 can be the same as the length of a single diaphragm after folding.

[0034] The intake mesh 3 can be one or more layers, and the specific design can be based on actual separation needs, for example, it can be 1 to 3 layers. When the intake mesh 3 has multiple layers, the mesh shape and distribution of each layer of intake mesh 3 can be consistent to form a regular gas flow channel; or the mesh positions of each layer of intake mesh 3 can be staggered to form a more complex gas flow path, enhance the gas turbulence of the intake channel and the membrane surface, and facilitate uniform gas distribution.

[0035] The air intake mesh 3 can be made of organic materials. Specifically, the material of the air intake mesh 3 can include at least one of polyester, polypropylene, polyamide, polyvinyl alcohol, polyacrylonitrile, polyvinyl chloride, protein fiber, and carbon fiber, preferably at least one of polyester and polypropylene.

[0036] Membrane 2 is the gas separation membrane. Different separation membranes can be selected for different gas separations. For example, the CO2 separation membrane used for flue gas carbon capture can selectively separate CO2 from background gases (nitrogen, oxygen, etc.). The main performance parameters can include CO2 permeation rate of 50~20000 GPU and CO2 to N2 separation factor of 2~1000.

[0037] The length of the separation unit is based on the length of a single diaphragm sheet after folding. The diaphragm sheet length can be 0.2~2.0m. The number of separation units can be designed according to actual separation needs, and there are no special restrictions in this disclosure. When there are multiple separation units, the multiple separation units can be stacked sequentially, and the gas production channel assembly 1 can be shared between the adjacent gas production sides of the previous separation unit and the next separation unit.

[0038] The gas separation membrane assembly disclosed herein may further include a gas collecting pipe for collecting the separated gas from the gas generation channel assembly 1. The gas collecting pipe may be a hollow pipe with a diameter of 5-60 mm. The gas collecting pipe may have multiple uniformly distributed gas collecting holes, with the total area of ​​the holes accounting for 5-70% of the surface area of ​​the gas collecting pipe. The gas collecting pipe may be made of metal (steel, cast iron, etc.), polyvinyl chloride, polyvinyl fluoride, polypropylene, etc. The separation unit is wound around the surface of the gas collecting pipe, and the unsealed end of the gas generation channel assembly 1 is connected to the gas collecting pipe, forming a spiral wound gas separation membrane assembly. In use, a mixed gas containing the target gas flows in from one end of the inlet mesh 3. The target gas is selectively introduced from the inlet side of the membrane 2 and discharged from the gas generation side, flowing along the flow channel provided by the gas generation channel assembly 1 (i.e., along...). Figure 1The gas flows perpendicular to the paper surface into the gas collecting pipe, and the unseparated gas is discharged from the other end of the air inlet mesh 3.

[0039] The gas separation membrane module disclosed herein is suitable for applications such as CO2 capture, high-purity gas preparation, and gaseous pollutant removal. It improves gas separation efficiency by optimizing the gas flow path and has good overall structural stability. It solves the technical problem of limited performance of gas separation membrane modules in the prior art and has important industrial application value.

[0040] The present disclosure is further illustrated below by way of examples, but is not intended to limit the present disclosure.

[0041] Example 1 Cut a CO2 gas separation membrane sheet (the membrane separation layer is polydimethylsiloxane, 1.1m long, 0.27m wide, CO2 permeation rate 7350 GPU, N2 permeation rate 650 GPU) and an inlet mesh (polypropylene, 0.5m long, 0.27m wide, 0.68mm thick, square mesh shape, mesh area 9mm²). 2 ), and the flow guide net (a planar crisscrossing polypropylene mesh, 0.7m long, 0.27m wide, and 0.3mm thick, with a hexagonal mesh shape and an average mesh area of ​​4mm²). 2 ), and guide cloth (polyester fiber woven mesh, 0.7m long, 0.27m wide, 0.18mm thick, with a weaving density of 14 / cm in the transverse direction and 14 / cm in the longitudinal direction), with a layer of guide mesh stacked on top of the guide cloth and bonded together with sealant. The thickness of the entire airflow channel assembly is 0.78mm. Prepare the gas collection pipe (axial effective area length 0.24m, pipe diameter 15mm, with round holes, and the hole area accounts for 60% of the surface area).

[0042] The diaphragm is folded in half lengthwise into two sections of 0.6m and 0.5m, with the gas-producing side inside. The gas-producing channel assembly is placed inside the folded diaphragm, and the air inlet mesh is placed on the opposite side. One end of the gas-producing channel assembly ( Figure 1 One end of the membrane (perpendicular to the paper surface) is connected to the gas collecting pipe, and the other end is stretched taut to lay it flat. Sealant is applied to both sides of the gas generating channel assembly and the opposite end of the gas collecting pipe. The folded membrane is then wrapped around the gas generating channel assembly and laid flat on it, with one folded end corresponding to one end of the gas collecting pipe. All layers are aligned, and the membrane is tightly rolled starting from the gas collecting pipe. After rolling, it is secured with tape. Once the tape is dry, 0.015m wide sections are cut from each side to form the gas separation membrane assembly. Its cross-sectional structure in the direction parallel to the gas collecting pipe is shown below. Figure 1 As shown, after rolling, the air inlet mesh 3 is attached to the air inlet side of the diaphragm 2 at the top and bottom respectively, and the air generation channel assembly 1 is attached to the air generation side of the diaphragm 2 at the top and bottom respectively; the end of the air generation channel assembly 1 is connected to the air collection pipe.

[0043] Example 2 The gas separation membrane module was prepared according to Example 1, except that the lengths of the membrane, air inlet mesh, and flow guide were changed to 1.7m, 0.8m, and 1m, respectively.

[0044] Example 3 The gas separation membrane module was prepared according to Example 1, except that only one layer of flow guiding mesh was laid on the flow guiding cloth, and the thickness of the entire gas generation channel module was 0.48 mm.

[0045] Example 4 A gas separation membrane module was prepared according to Example 1, except that the thickness of the flow guide mesh was 0.15 mm.

[0046] Example 5 The gas separation membrane module was prepared according to Example 1, except that the mesh area of ​​the flow guide net was 1 mm². 2 .

[0047] Example 6 The gas separation membrane module was prepared according to Example 1, except that the thickness of the flow guide cloth was 0.3 mm and the weaving density was 20 / cm in the transverse direction and 20 / cm in the longitudinal direction.

[0048] Comparative Example 1 A gas separation membrane module was prepared according to Example 1, except that a composite gas generation channel module was not used, and only a flow guide cloth was used on the gas generation side of the membrane.

[0049] Test case The gas separation performance of the gas separation membrane modules in the examples and comparative examples was tested. The test method was as follows: a mixture of CO2 and N2 (simulating flue gas with 15% CO2 and 85% N2) was used as the gas to be separated and introduced into the gas separation membrane module. The gas was collected by the gas collection pipe. The CO2 permeation rate and N2 permeation rate were determined by a known method (such as the literature report "Industrial-scale spiral-wound facilitated transport membrane modules for post-combustion CO2 capture: Development, investigation and optimization", H. Wu et al. JMS 670 (2023)). The membrane performance utilization rate of the membrane module was calculated according to the following formula. The results are listed in Table 1.

[0050] Membrane performance utilization rate = (Module CO2 permeation rate / Membrane CO2 permeation rate) × 100% Table 1

[0051] As can be seen from Table 1, the gas separation membrane module disclosed herein can fully utilize the membrane performance and achieve improved separation effect.

[0052] The preferred embodiments of the present disclosure have been described in detail above with reference to the accompanying drawings. However, the present disclosure is not limited to the specific details of the above embodiments. Within the scope of the technical concept of the present disclosure, various simple modifications can be made to the technical solutions of the present disclosure, and these simple modifications all fall within the protection scope of the present disclosure.

[0053] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, this disclosure will not describe the various possible combinations separately.

[0054] Furthermore, various different embodiments of this disclosure can be combined in any way, as long as they do not violate the spirit of this disclosure, they should also be regarded as the content disclosed in this disclosure.

Claims

1. A gas separation membrane module, characterized in that, The gas separation membrane assembly includes at least one separation unit, the separation unit including a membrane, an air inlet mesh and a gas generation channel assembly, the membrane having an opposite air inlet side and a gas generation side, the air inlet mesh being attached to the air inlet side, the gas generation channel assembly being attached to the gas generation side and forming a sealed structure with the gas generation side, the gas generation channel assembly including a layered guide cloth and at least one layer of guide mesh.

2. The gas separation membrane module according to claim 1, wherein, The gas generation channel assembly includes a first guide net, a guide cloth, and a second guide net stacked in sequence. The first guide net, the guide cloth, and the second guide net are bonded together by a sealant or a pressing process, and the gas generation channel assembly is sealed and attached to the gas generation side.

3. The gas separation membrane module according to claim 1, wherein, The thickness of the flow guide net is 0.1~2mm; and / or, the mesh area of ​​the flow guide net is 0.5~25mm². 2 .

4. The gas separation membrane module according to claim 1, wherein, The material of the guide net includes at least one of polypropylene, polyester, polyamide, polyvinyl alcohol, polyacrylonitrile, polyvinyl chloride, protein fiber, and carbon fiber.

5. The gas separation membrane module according to claim 1, wherein, The thickness of the flow guiding cloth is 0.1~0.3mm.

6. The gas separation membrane module according to claim 1, wherein, The material of the flow-guiding cloth includes at least one of polyester, polypropylene, polyamide, polyvinyl alcohol, polyacrylonitrile, polyvinyl chloride, protein fiber, and carbon fiber.

7. The gas separation membrane module according to claim 1, wherein, The weaving density of the flow guiding fabric is 5~20 / cm in the transverse direction and 10~30 / cm in the longitudinal direction.

8. The gas separation membrane module according to claim 1, wherein, The thickness of the air intake mesh is 0.1~2mm; and / or, the mesh area of ​​the air intake mesh is 0.5~25mm². 2 .

9. The gas separation membrane module according to claim 1, wherein, The air intake mesh is made of at least one of polyester, polypropylene, polyamide, polyvinyl alcohol, polyacrylonitrile, polyvinyl chloride, protein fiber, and carbon fiber.

10. The gas separation membrane assembly according to claim 1, wherein, The gas separation membrane assembly further includes a gas collecting tube, the separation unit is wound around the surface of the gas collecting tube, and one end of the gas generating channel assembly is connected to the gas collecting tube.

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