Membrane module

Abstract

The membrane module comprises at least one pressure vessel (2) having a cylindrical wall (7). A first end (5) of the pressure vessel (2) is closed by a first end cap (11), and a second end (6) of the pressure vessel (2) is closed by a second end cap (12). The membrane module further comprises at least one membrane cartridge (9) arranged inside the pressure vessel (2), each of which comprises a plurality of membrane envelopes arranged in a stack. Each membrane envelope comprises two membranes and one or more first spacers between the membranes, each arranged on a carrier material. Each membrane cartridge (9, 9a) further comprises a second spacer between the membrane envelopes. The membrane cartridge (9) further comprises one or more permeate tubes (19) which are fluidly connected to at least one permeate outlet (17).

Description

Technical Field

[0001] The present invention relates to a membrane module for separating a fluid supply stream into a permeate stream and a retentate stream, and more particularly to a membrane module that can operate at high pressure.

Background Art

[0002] Membrane-based separation processes have found numerous applications in various industries over the past several decades. Applications have been found in fields such as water, energy, chemical, petrochemical, and pharmaceutical industries. Their increasing applicability is due to the ability to mass-produce highly permeable and essentially defect-free membranes and the ability to assemble these membranes into compact, efficient, and economic membrane modules with high membrane surface area.

[0003] Industrial membrane separation requires that a large membrane surface area be economically and effectively packaged. These packages are referred to as membrane modules. Generally, there are four basic types of membrane modules, namely, plate and frame type, spiral wound type, tubular type, and hollow fiber type membrane modules. Effective module design is one of the important qualities, which determines the commercial success of membrane-based separation units.

[0004] A membrane module separates a fluid supply stream into a permeate stream and a retentate stream. The stream that permeates through the membrane and is separated from the feed material is referred to as the permeate stream, and the stream from which the permeate has been removed and is dispensed from the separation unit without permeating through the membrane is referred to as the retentate stream. Some industrial applications benefit from the application of high pressure in addition to a large surface area. Such processes include, for example, the separation of carbon dioxide from the combustion exhaust gases of industrial and power generation CO2 emitters. The carbon dioxide separated as a permeate using renewable energy can be converted into usable carbon-based products such as fuels or polymers, or stored underground, or used as a nutrient for algae.

[0005] The use of membrane technology for large-scale carbon dioxide capture from major industrial combustion flue gas emissions requires ultra-large membrane areas. Generally, membrane modules in the form of plate and frame modules are preferred for large-area applications. Membranes that will be filled into plate and frame modules are readily available. However, one drawback is that, to date, plate and frame modules have not been able to operate above ambient pressures, for example, 120 kPa or above. In addition to the large membrane area, the membrane and space required to accommodate such a large membrane area would therefore be desirable to also operate membrane separation at high pressures, such as absolute pressures of 120 kPa or above.

[0006] For example, EP 3 227 004 Al concerns membrane modules whose components are housed within 20-foot, 40-foot, 45-foot HC, 45-foot PW, or 53-foot HC containers. Membrane modules provide a large membrane area, thereby reducing the number of individual membrane modules required in practical applications. However, membrane modules are not capable of operating at elevated pressures above approximately 120 kPa, as the container housing cannot withstand such operating pressures.

[0007] Alternatively, the membrane can also be arranged in the form of a flat sheet membrane, which is wound in a spiral and contained within a tubular housing (a spirally wound module), typically 40–80 m in length. 2 It contains a membrane area of ​​[value missing]. The tubular housing can withstand absolute operating pressures exceeding 1 MPa. However, this approach is prohibitively expensive due to the large number (thousands) of tubular housings that would be required for large-scale carbon dioxide capture. Spiral-wound modules are both expensive to manufacture and difficult to interconnect in order to be suitable for use in large-scale operations.

[0008] Another alternative option for arranging gas phase separation membranes within a membrane module is the use of hollow fiber membranes. Hollow fiber membranes utilize thousands of long, porous filaments ranging in width from 0.1 to 3.5 mm, which are insulated in a fixed position within a shell. Each filament is extremely thin in diameter and flexible. Hollow fibers can be found in use in various types of membrane processes, ranging from microfiltration to reverse osmosis and gas separation. However, the geometry of hollow fiber membranes is unsuitable for the type of membrane used in this invention for carbon dioxide separation from combustion flue gas, as it causes a large pressure drop throughout the entire length of the membrane, preventing the application of the thin polymer film required for carbon dioxide separation. [Overview of the project] [Means for solving the problem]

[0009] Therefore, an object of the present invention is to provide and operate a membrane module that has a large membrane area, is readily available, and is capable of operating at absolute pressures of 120 kPa or above 120 kPa.

[0010] The above objective is achieved by the membrane module described in claim 1. Preferred embodiments are described in the dependent claims.

[0011] According to the present invention, a membrane module comprising a permeable material and a retainate material is adapted to separate a fluid supply flow into a permeable flow and a retainate flow. The membrane module comprises at least one pressure vessel having a cylindrical wall that extends along a longitudinal axis from a first end to a second end and encloses an internal space. The first end of the pressure vessel is closed by a first end cap, and the second end of the pressure vessel is closed by a second end cap. At least one of the first end cap and the cylindrical side wall is provided with a fluid inlet for receiving the fluid supply flow. The second end cap is provided with a retainate outlet for discharging the retainate flow. At least one of the first end cap and the second end cap is further provided with one or more permeate outlets for discharging the permeable flow.

[0012] The membrane module further comprises at least one membrane cartridge arranged inside a pressure vessel, each of which comprises a plurality of membrane envelopes arranged in a stack. Each membrane envelope comprises two membranes arranged on a carrier material and one or more first spacers between the membranes that keep the membranes separated from each other to allow a free flow cross-section for permeate flow through the membrane envelope. The membranes have edges along which the membranes of the membrane envelope are connected to each other to prevent fluid supply flow and retainate flow from permeating into the membrane envelope.

[0013] Each membrane cartridge further comprises a second spacer between the membrane envelopes, which keeps the membrane envelopes spaced apart to allow a free flow cross-section for the permeate flow of the fluid supply flow and / or retained flow in the flow direction. Each membrane cartridge further comprises one or more permeate tubes, which extend laterally with respect to the flow direction of the fluid supply flow and are fluid-connected to at least one permeate outlet. The one or more permeate tubes have one or more radial openings through which the permeating material from the membrane envelope arrives in the one or more permeate tubes.

[0014] This invention enables the packaging of large-area membranes within compact, low-cost housings, allowing membrane modules to operate at elevated pressures of 120 kPa or above. This improves membrane performance and enables cost-effective and economically viable use. Furthermore, this invention enables the realization of counterflow patterns for each feed and permeate flow in stacked membrane envelopes, thus allowing for improved use of available separation driving forces.

[0015] Preferably, the permeate tubes are perforated or contain gaps, and the through-holes are pushed into the membrane envelope and spacers. Gas leakage from the high-pressure fluid supply flow is prevented by installing sealing rings around the permeate tubes between the individual membrane envelopes and the first and last envelopes of the stack, and adjacent to the housing material. The seal is ensured, for example, by using threaded ends of the tubes and sealed threaded caps. The permeate tubes of individual stacks may be connected to an internal manifold system of the membrane module that connects the permeate tubes to one or more permeate outlets of the pressure vessel.

[0016] In connection with this invention, the term "pressure" should be understood to refer to absolute pressure.

[0017] In embodiments of the present invention, the membrane module is configured to operate within an absolute pressure range of the fluid supply flow of 100 kPa to 2 MPa, preferably 120 kPa to 1.5 MPa, and more preferably 150 kPa to 1.0 MPa. To withstand the absolute pressure range of the fluid supply flow as defined above, the cylindrical wall of the pressure vessel has a thickness of 3 mm to 7 mm, preferably 4 mm to 6 mm, and more preferably about 5 mm. To withstand the absolute pressure range of the fluid supply flow as defined above, the first and second end caps have a thickness of 5 mm to 10 mm, preferably 6 mm to 9 mm, and more preferably about 7 mm.

[0018] As used in this invention, the term "about" is used to specify an acceptable deviation from a standard value. In relation to the thickness of the cylindrical wall of the pressure vessel or the thickness of the first and second end caps, the acceptable deviation from the standard value is about ±0.2 mm, preferably ±0.1 mm.

[0019] The higher the pressure, the lower the volume of gas in the permeate flow exiting the membrane module. Due to the higher operating pressure, the size of the support equipment, for example, the number of vacuum pumps required on the permeate side of the membrane module, can be reduced. Suitable for the pressure vessel and the pressure range defined above, the material has material number 1.4571 in accordance with European standards (EN) and has a pressure of 270 N / mm² at room temperature. 2 This is X6CrNiMoTi17-12-2, which has a yield strength of 1% (Rpl.0).

[0020] According to the present invention, at least one membrane cartridge has a rectangular parallelepiped housing. The rectangular parallelepiped shape preferably allows for stacking of rectangular membrane envelopes within the housing. Preferably, the housing is constructed from thin stainless steel plates. Optionally, other metal or plastic materials such as glass-reinforced plastic (GRP) may also be used.

[0021] According to the present invention, each pressure vessel comprises an annular body positioned radially inward between the cylindrical wall of the pressure vessel and the rectangular prism housing of at least one membrane cartridge. Preferably, the annular body surrounds the rectangular prism housing of at least one membrane cartridge in a circumferential direction around the longitudinal axis of the pressure vessel.

[0022] In embodiments of the present invention, the pressure vessel further comprises a first end piece and a second end piece, each sealing at least one membrane cartridge to the first end cap and the second end cap, respectively. Optionally, the first end piece includes an equalization port, which is configured to provide a fluid connection between the fluid inlet and the annular body at the first end cap so that the pressure at the fluid inlet and the annular body are equalized. Alternatively, the equalization port may be omitted, and the annular body may be directly fluidically connected to the fluid inlet to provide pressure equalization. If the membrane module comprises a plurality of membrane cartridges arranged in series inside the pressure vessel, the equalization port may generally be arranged between any of the membrane cartridges. However, it is preferable that the first end piece includes an equalization port. The equalization port may be formed as a through hole, a circumferential gap, or any passage within the first end piece, which allows fluid flow from the fluid inlet toward the annular body.

[0023] As the pressure at the fluid inlet is equalized with the pressure inside the annular body of the pressure vessel, the membrane cartridge itself does not retain pressure. While not wishing to be bound by any particular theory, the annular body, using reasonable wall thicknesses of the membrane cartridge and the pressure vessel, allows for the absorption of overpressure of the supply flow within the membrane cartridge relative to atmospheric pressure. As the pressure inside the annular body is equalized with the pressure at the fluid inlet of the pressure vessel, any force acting on the membrane cartridge radially outward toward the cylindrical wall of the pressure vessel is absorbed by the supply fluid inside the annular body and passed through the cylindrical wall of the pressure vessel.

[0024] The maximum pressure difference between the annular body and the internal pressure in at least one membrane cartridge is equal to the sum of the pressure differences across each of the membrane cartridges inside the pressure vessel through which the fluid supply flow is induced. For example, if four membrane cartridges are arranged in series inside the pressure vessel so that the fluid supply flow is induced successively through the four membrane cartridges, the maximum pressure difference is approximately 2 kPa to 20 kPa. Once the pressure between the annular body and the fluid inlet is equalized, there is no flow through the annular body in the pressure vessel.

[0025] Thus, a conventional plate and frame type module with a conventional flat sheet envelope membrane inserted therein can be operated at an elevated pressure of 120 kPa or above 120 kPa so that the ambient space around the plate and frame type module captures any overpressure and directs it to the walls and end caps of the pressure vessel, thereby protecting the membrane stack.

[0026] In another embodiment of the present invention, the membrane module comprises a plurality of membrane cartridges arranged in series inside the pressure vessel along the longitudinal axis, and the rectangular parallelepiped housing of the membrane cartridge is sealed to each other such that the fluid supply flow flows through the plurality of membrane cartridges before exiting the membrane module as the retentate flow. Each membrane cartridge comprises one or more permeate tubes into which the permeate material from the membrane envelope arrives and flows towards the permeate outlet. The series arrangement of the plurality of membrane cartridges individually enables the withdrawal of a plurality of permeate flows, i.e., at least one permeate flow per membrane cartridge, using internal piping. This enables, for example, the combination of two permeate flows from two successive membrane cartridges, and thus the realization of a two-stage sequential removal process using only one pressure vessel. The permeate flows, each having a different carbon dioxide concentration, can be mixed to produce a permeate flow with a defined carbon dioxide concentration.

[0027] In an embodiment of the present invention, up to 12 membrane cartridges, preferably up to 10 membrane cartridges, more preferably up to 8 membrane cartridges, for example, 4 membrane cartridges, are arranged in series inside a pressure vessel. The number of membrane cartridges arranged inside the pressure vessel, and thus the size of the pressure vessel, may be selected according to the size of the available assembly space. For example, if the membrane module is to be stored inside a 40-foot PW or HC container, up to 8 membrane cartridges are arranged inside one pressure vessel such that the pressure vessel extends over the full length of the container. The membrane cartridges arranged in series preferably have the same geometric shape.

[0028] The length of the membrane envelope, and thus the length of each membrane cartridge comprising the stacked membrane envelopes, can be adjusted according to the process requirements. The pressure drop between the feed and permeate can be adjusted by selecting the applied feed and permeate pressures, but it should also be observed that there is also a certain pressure drop resulting from the feed flow that flows parallel along the membrane surface. Naturally, this pressure drop increases with the length of the membrane envelope.

[0029] In another embodiment of the present invention, the pressure vessel comprises a removal mechanism which enables the removal of at least one membrane cartridge from the pressure vessel in response to an operation. When one or more membrane cartridges are damaged and need to be replaced, the removal mechanism enables the removal of one or more membrane cartridges from the pressure vessel.

[0030] In embodiments of the present invention, the removal mechanism comprises rails arranged inside the pressure vessel parallel to its longitudinal axis, and at least one membrane cartridge comprises a pulley configured to roll along the rails so that at least one membrane cartridge is movable out of the pressure vessel along the rails. Preferably, the removal mechanism further comprises removal means which, depending on the operation, allow the removal of first and / or second end caps from the pressure vessel to access the membrane cartridges. The pulleys and rails may be configured to allow the movement of one or more membrane cartridges toward the first and second ends of the pressure vessel, respectively. The movement of the membrane cartridges may be performed manually by an operator. A crane may be used, at will, to lift one or more cartridges one by one out of the pressure vessel.

[0031] In another embodiment of the present invention, the membrane cartridges are arranged in two cartridge rows, each cartridge row comprising a plurality of membrane cartridges arranged in series, and the two cartridge rows are arranged in parallel so that the fluid supply flow flows through both cartridge rows simultaneously. Generally, it is desirable to minimize the pressure drop across a plurality of membrane cartridges arranged in series. Arranging two cartridge rows in parallel, each comprising the same number of membrane cartridges as one single row of membrane cartridges arranged in series, reduces the pressure drop across each of the two cartridge rows. The pressure drop may therefore be selected individually depending on the membrane used, the fluid supply flow pressure, and the available assembly space. Preferably, the rectangular housings of the membrane cartridges in each of the two cartridge rows are sealed to each other so that the fluid supply flows through both cartridge rows simultaneously before exiting the membrane module (1') as separate retained flows (16).

[0032] In embodiments of the present invention, two rows of cartridges are arranged along a longitudinal axis with a gap between them, and the fluid inlet at the first end cap or the cylindrical side wall of the pressure vessel is fluidically connected to the gap between the two rows of cartridges, and the two rows of cartridges are further arranged so that the fluid supply flow is divided in the gap and flows in opposite directions along the longitudinal axis through both rows of cartridges toward the first and second end caps, respectively. Preferably, the membrane module includes a supply flow conduit that connects to the fluid inlet at the first end cap with a gap between the two rows of cartridges.

[0033] In another embodiment of the present invention, the membrane module comprises a plurality of pressure vessels, preferably up to 10, more preferably up to 6, and most preferably 4, and further comprises a 20-foot, 40-foot, 45-foot HC, 45-foot PW, or 53-foot HC container in which the pressure vessels are housed. Thus, despite its relatively large volume and weight, the membrane module can be transported and handled in a very simple and cost-effective manner. In connection with the present invention, the term “20-foot, 40-foot, 45-foot, 53-foot PW or HC shipping container” should be understood as a pallet-wide (PW) or high-cube (HC) ISO standard and derivative multi-transport-means-compatible shipping container of 20-foot, 40-foot, 45-foot, or 53-foot length.

[0034] The above objectives can also be achieved by the method described in claim 12. Preferred embodiments are described in the individual dependent claims.

[0035] This method, comprising a permeable material and a retainate material, is adapted for separating a fluid supply flow into a permeable flow and a retainate flow. According to this method, a. A membrane module as described above is provided, b. The fluid supply flow is guided into at least one pressure vessel through the fluid inlet. c. The fluid supply flow flows through at least one membrane cartridge inside the pressure vessel in the direction of the retainate outlet, and during the permeate flow through at least one membrane cartridge, the permeate material flows through the membrane into the membrane envelope, thereby separating the fluid supply flow into a permeate flow within the membrane envelope and a retainate flow between the membrane envelopes. d. The permeate flow flows from the membrane envelope through one or more radial openings into one or more permeate tubes, through one or more permeate tubes to one or more permeate outlets, where it is discharged. The retainate flow flows between the membrane envelopes and, after passing through at least one membrane cartridge, is discharged through the retainate outlet.

[0036] This method enables the use of large-area membranes within a compact, low-cost enclosure, allowing membrane modules to operate at elevated pressures exceeding 120 kPa. This provides a cost-effective and economically viable method for operating membrane envelopes within membrane modules.

[0037] In embodiments of the present invention, the membrane module comprises a plurality of membrane cartridges arranged in series inside a pressure vessel along a longitudinal axis, and in step e, the retainate flow flows from between the membrane envelopes to the subsequent membrane cartridge of the plurality of membrane cartridges arranged in series, and enters the subsequent membrane cartridge as a fluid supply flow after removal, and after passing through the membrane cartridges arranged in series, the retainate flow is discharged through the retainate outlet. This enables the provision of a multi-stage sequential removal process. Furthermore, the use of a plurality of membrane cartridges in series allows for the individual extraction of multiple permeate flows, for example, one permeate flow from each membrane cartridge, using internal piping. In this method, two or more permeate flows having different carbon dioxide concentrations can be combined, and flows having a predefined carbon dioxide concentration can be mixed.

[0038] In another embodiment of the present invention, the fluid supply flow and the permeate flow flow through at least one membrane cartridge, passing each other at least partially in a counterflow manner. The counterflow pattern allows for optimal use of the applied separation driving force.

[0039] In embodiments of the present invention, the pressure vessel further comprises a first end piece and a second end piece, each sealing at least one membrane cartridge to the first end cap and the second end cap, respectively.

[0040] According to the present invention, each pressure vessel comprises an annular body positioned radially inward between the cylindrical wall of the pressure vessel and the rectangular housing of at least one membrane cartridge, the fluid inlet being fluidly connected to the annular body, and the fluid supply flow entering at least one pressure vessel and partially flowing toward the annular body, thereby equalizing the pressure at the fluid inlet and the annular body. Once the pressure between the annular body and the fluid inlet is equalized, there is no further flow through the annular body of the pressure vessel.

[0041] In one embodiment of the present invention, the first end piece is provided with an equalization port, which is configured to provide a fluid connection between the fluid inlet at the first end cap and the annular body, through which the fluid supply flow enters at least one pressure vessel and flows partially through the equalization port, thereby equalizing the pressure at the fluid inlet and the annular body. As the pressure at the fluid inlet is equalized with the pressure inside the annular body of the pressure vessel, the force acting on the membrane cartridge is reduced. The maximum pressure difference between the annular body and the internal pressure in at least one membrane cartridge is equal to the sum of the differential pressures across each of the membrane cartridges inside the pressure vessel through which the fluid supply flow is induced. For example, if four membrane cartridges are arranged in series inside the pressure vessel so that the fluid supply flow is induced successively through the four membrane cartridges, the maximum pressure difference is about 2 kPa to 20 kPa. Once the pressure between the annular body and the fluid inlet is equalized, there is no flow through the annular body of the pressure vessel.

[0042] In another embodiment of the present invention, the fluid supply flow has an absolute pressure range of 100 kPa to 2 MPa, preferably 100 kPa to 1.5 MPa, and more preferably 150 kPa to 1.0 MPa. Higher pressure reduces the gas volume of the permeate flow exiting the membrane module. Due to the higher operating pressure, the size of the support equipment, for example, the number of vacuum pumps required on the retaining side of the membrane module can be reduced.

[0043] In embodiments of the present invention, the membrane cartridges are arranged in two rows of cartridges, with each row of cartridges comprising a gap between multiple membrane cartridges arranged in series, and the two rows of cartridges are arranged in parallel, and the fluid supply flow flows simultaneously through both rows of cartridges in opposite directions, along the longitudinal axis, from the gap through both rows of cartridges towards the first end cap and the second end cap, respectively. Generally, it is desirable to minimize the pressure drop across multiple membrane cartridges arranged in series. Arranging two rows of cartridges in parallel, each comprising the same number of membrane cartridges as a single row of membrane cartridges arranged in series, reduces the pressure drop. The pressure drop may therefore be individually selected depending on the membrane used, the fluid supply flow pressure, and the available assembly space. [Brief explanation of the drawing]

[0044] The present invention will be described in detail with reference to the following figures.

[0045] [Figure 1] Figure 1 shows a perspective view of a membrane module according to the present invention, which is stored in a 40-foot container. [Figure 2] Figure 2 shows a schematic diagram of a pressure vessel containing multiple membrane cartridges. [Figure 3] Figure 3 shows a cross-sectional view through the stacked membrane envelope. [Figure 4] Figure 4 shows the flow directions of the fluid supply flow / retained flow and permeate flow within a single membrane envelope. [Figure 5]Figure 5 shows a schematic diagram of a second embodiment of a pressure vessel containing multiple membrane cartridges. [Figure 6] Figure 6 shows a schematic diagram of a system comprising a membrane module according to the present invention. [Modes for carrying out the invention]

[0046] Detailed description of the invention Figure 1 shows a membrane module 1 comprising a permeable material and a retainate material for separating a fluid supply flow into a permeable flow and a retainate flow. In particular, membrane module 1 is adapted for large-scale carbon dioxide capture from industrial combustion flue gas emissions in, for example, cement plants, steel plants, and coal-fired and waste-to-energy plants. In combination with the present invention, the term “large-scale carbon dioxide capture” should be understood as the ability of the membrane module to capture carbon dioxide from industrial combustion flue gas emissions of approximately 0.6 to 0.8 tons of CO2 / ton of cement in a cement plant and approximately 1.4 to 2 tons of CO2 / ton of steel in a steel plant, where the combustion flue gas emissions have a CO2 concentration of up to 30%. With respect to thermal and power facilities, the membrane module is capable of capturing carbon dioxide from industrial combustion flue gas emissions of approximately 0.4 tons of CO2 / MWh in combustion flue gas and 3 to 16% CO2.

[0047] The combustion exhaust gas, in gaseous form, enters the membrane module 1 as a fluid supply flow and is separated into carbon dioxide, which includes permeate and retainate flows. The membrane module 1 is configured to operate within an absolute pressure range of the fluid supply flow of 100 kPa to 2 MPa, preferably 100 kPa to 1.5 MPa, and more preferably 150 kPa to 1.0 MPa.

[0048] The membrane module 1 comprises four pressure vessels 2 and a 40-foot container 3 in which the pressure vessels 2 are housed. Each pressure vessel 2 has a cylindrical wall 7 that extends along a longitudinal axis 4 from a first end 5 to a second end 6, enclosing an internal space 8.

[0049] The membrane module 1 further comprises 32 membrane cartridges 9, with eight membrane cartridges 9 housed within each of the pressure vessels 2. The membrane cartridges 9 in each pressure vessel 2 are arranged in series along the longitudinal axis 4 inside the pressure vessel 2. Each membrane cartridge 9 has a rectangular parallelepiped housing 10. To improve understanding of Figure 1, the container walls and the cylindrical walls of the pressure vessels 2 are made transparent.

[0050] Figure 2 shows a detailed view of the membrane module 1, and in particular, one of the pressure vessels 2 of the membrane module 1.

[0051] The first end 5 of the pressure vessel 2 is closed by a first end cap 11, and the second end 6 of the pressure vessel 2 is closed by a second end cap 12. The first end cap 11 is provided with a fluid inlet 13 for receiving a fluid supply flow 14. The second end cap 12 is provided with a retainate outlet 15 for discharging a retainate flow 16. The first end cap 11 and the second end cap 12 are provided with one or more permeate outlets 17 for discharging a permeate flow 18.

[0052] Eight membrane cartridges 9 are arranged in series inside the pressure vessel 2 along the longitudinal axis 4. The rectangular prism housings 10 of the membrane cartridges 9 are sealed to each other so that the fluid supply flow 14 flows through the eight membrane cartridges 9 before exiting the membrane module 1 as retained flow 16. Each membrane cartridge 9 is provided with one or more permeate tubes 19 to guide the permeate flow 18 out of each membrane cartridge 9. Each permeate tube 19 extends laterally with respect to the flow direction of the fluid supply flow 14 and is fluidly connected to at least one permeate outlet 17.

[0053] Each pressure vessel 2 includes an annular body 20 positioned radially inward between the cylindrical wall 7 of the pressure vessel 2 and the rectangular housing 10 of at least one membrane cartridge 9. The pressure vessel 2 further includes a first end piece 21 and a second end piece 22, which seal at least one membrane cartridge 9 to a first end cap 11 and a second end cap 12, respectively. The first end piece 21 includes an equalization port 23 formed as a through-hole, which is configured to provide a fluid connection between the fluid inlet 13 and the annular body 20 at the first end cap 11 so that the pressures at the fluid inlet 13 and the annular body 20 are equalized. Alternatively, the first end piece 21 may be omitted so that the fluid supply flow entering the fluid inlet 13 flows directly through the annular body 20, thereby equalizing the pressures at the fluid inlet 13 and the annular body 20.

[0054] The pressure vessel is equipped with a removal mechanism (not shown) which, in response to operation, allows for the removal of the membrane cartridge 9 from the pressure vessel 2. The removal mechanism includes rails arranged inside the pressure vessel 2 parallel to its longitudinal axis 4, and the multiple membrane cartridges 9 are equipped with pulleys configured to roll along the rails so that the multiple membrane cartridges 9 can move out of the pressure vessel 2 along the rails.

[0055] As shown in Figures 3 and 4, each membrane cartridge 9 comprises a plurality of membrane envelopes 24 arranged in a stack configuration. Each membrane envelope 24 comprises two membranes 25 arranged on a carrier material and one or more first spacers 26 between the membranes 25 that keep the membranes 25 separated from each other to allow a free flow cross-section for permeate flow 18 through the membrane envelope 24. The membranes 25 have edges along which the membranes 25 of the membrane envelope 24 are connected to each other to prevent the fluid supply flow 14 and retainate flow 16 from permeating into the membrane envelope 24.

[0056] Each membrane cartridge 9 further comprises a second spacer 27 between the membrane envelopes 24, which keeps the membrane envelopes 24 spaced apart to allow a free flow cross-section for the permeating fluid supply flow 14 and / or retained flow 16 in the flow direction. The first and / or second spacers 26, 27, independently of each other, may comprise or consist entirely of a plastic fabric.

[0057] One or more permeate tubes 19 are provided with one or more radial openings through which the permeate flow can flow from the membrane envelope 24 into the one or more permeate tubes 19. Seals may be fitted over the one or more permeate tubes 19 between the membrane envelopes 24, thereby preventing contact between the fluid supply flow 14 and / or retainate flow 16 and the one or more permeate tubes 19. Both the fluid supply flow 14 and the retainate flow 16, which are both present between the membrane envelopes 24, are thus prevented from permeating into the one or more permeate tubes 19.

[0058] The membrane envelopes 19 and their functions are described in detail in European Patent Application EP 3 227 004 Al (which is incorporated herein by reference as a whole).

[0059] Below, a method for separating a fluid supply flow into a permeate flow and a retainate flow, comprising a permeate material and a retainate material, is described with reference to Figures 1-4.

[0060] In the first step, a membrane module as described above is provided, the membrane module 1 comprising four pressure vessels 2 as shown in Figure 1 and eight membrane cartridges 9 per pressure vessel 2. The membrane cartridges 9 are arranged in series inside each pressure vessel 2 along the longitudinal axis 4.

[0061] A fluid supply flow 14 is guided into the four pressure vessels 2 through the fluid inlet 13. Entering the pressure vessels 2, the fluid supply flow 14 partially flows through equalization ports 23 in each first end piece 21 of the pressure vessels 2, thereby equalizing the pressure in the fluid inlet 13 and the annular body 20. The fluid supply flow 14 has an absolute pressure range of 100 kPa to 2 MPa, preferably 100 kPa to 1.5 MPa, and more preferably 150 kPa to 1.0 MPa.

[0062] The fluid supply flow 14 flows through the membrane cartridges 9 inside the pressure vessel 2 in the direction of the retainate outlet 17. During the permeate flow through the eight membrane cartridges 9 per pressure vessel 2, the permeate material flows through the membrane 25 into the membrane envelope 24, thereby separating the fluid supply flow 14 into the permeate flow 18 within the membrane envelope 24 and the retainate flow 16 between the membrane envelopes 24.

[0063] The permeate flow 18 flows from the membrane envelope 24 through one or more radial openings into one or more permeate tubes 19, and flows through one or more permeate tubes 19 to one or more permeate outlets 17, where it is discharged.

[0064] In particular, as can be seen from Figure 4, the fluid supply flow 14 and the permeate flow 18 flow through each of the membrane cartridges 9 in a counter-flow manner, passing over each other, at least partially.

[0065] The retainate flow 16 flows from between the membrane envelopes 24 to the subsequent membrane cartridges 9 of the eight membrane cartridges 9 arranged in series, and enters the subsequent membrane cartridges 9 as the fluid supply flow 14 after it has been removed. Once it has passed through the eight membrane cartridges 9 per pressure vessel 2, the retainate flow 16 is discharged through the retainate outlet 15.

[0066] Figure 5 shows a second embodiment of the pressure vessel 2, which includes eight membrane cartridges. The pressure vessel 2' differs from that shown in Figure 2 in that the membrane cartridges 9 are arranged in two cartridge rows 28, with each cartridge row 28 comprising four membrane cartridges arranged in series. The two cartridge rows 28 are arranged along the longitudinal axis 4 of the pressure vessel 2', with a gap 29 between them. Fluid inlets 13 are arranged around the circumference of the cylindrical side wall 7 of the pressure vessel 2' and are fluidly connected to the gap 29 between the two cartridge rows 28. Alternatively, the fluid inlets 13 may be located at the first end cap 11 of the pressure vessel 2'.

[0067] The first end piece 21 and the second end piece 22 seal the membrane cartridges 9 of one of the cartridge rows 28 and the other cartridge rows 28 to the first end cap 11 and the second end cap 12, respectively.

[0068] Two cartridge rows 28 are arranged in parallel so that the fluid supply flow 14 flows simultaneously through both cartridge rows 28. The fluid supply flow 14 is divided in the gap 29 and flows in opposite directions along the longitudinal axis 4 through both cartridge rows 28 toward the first end cap 11 and the second end cap 12, respectively. The first end cap 11 and the second end cap 12 each have retainate outlets 15 for discharging retainate flow.

[0069] The fluid inlet 13 is fluidically connected to the annular body 20 so that the pressure in the fluid inlet 13 and the annular body 20 are equalized. Preferably, there is no piping between the fluid inlet 13 and the gap so that the fluid supply flow 14 flows through the annular body 20 toward the gap 29 between the cartridge rows 28 as it enters the pressure vessel 2'. In accordance with the equalization of pressure in the annular body 20 and the gap 29, a sustained flow of the fluid supply flow 14 is established through both of the cartridge rows 28 toward the first end cap 11 and the second end cap 12, respectively. In accordance with the pressure equalization, there is no flow through the annular body 20. Therefore, in combination with the second embodiment of the pressure vessel 2', there is no need for an equalization port 23.

[0070] Figure 6 shows a system 30 comprising a membrane module 1 according to the present invention. For simplicity, the membrane module 1 comprises only one pressure vessel 2 and three membrane cartridges 9 arranged in series within the pressure vessel 2. However, the membrane module 1 may comprise more than three membrane cartridges, for example, 32 membrane cartridges 9 arranged within four pressure vessels 2, as shown in Figure 1.

[0071] An inlet combustion exhaust gas compressor 31 is positioned in the fluid direction of the fluid inlet flow 14 prior to the fluid inlet 13 so that, for example, combustion exhaust gas from the combustion stack is compressed to an operating pressure before entering the membrane module 1. An expander 32 is positioned in the fluid direction of the retainate flow 16 after the retainate outlet 15 so that the retainate flow 16 is preferably expanded to atmospheric pressure after being dispensed from the membrane module 1. The expanded retainate flow 16 may be returned to the combustion stack.

[0072] The membrane module 1 comprises a first permeate outlet 17a, a second permeate outlet 17b, and a third permeate outlet 17c, each connected to one of the membrane cartridges 9. The first permeate outlet 17a is connected to a transport compressor 33, which is adapted to compress the carbon dioxide containing the permeate flow 18a dispensed from the first permeate outlet 17a to a transport pressure. The compressed retainate flow 18a may be transported to a storage tank or used directly in a further process step.

[0073] The second permeate outlet 17b is connected to a step compressor 34 and subsequently to a further membrane cartridge 9a. The further membrane cartridge 9a may be part of the second membrane module 1'. The step compressor 34 is configured to compress the permeate flow 18b being dispensed from the second permeate outlet 17b so that the compressed permeate flow 18b enters the further membrane cartridge 9a. The retainate flow 16a dispensed from the further membrane cartridge 9a is depressurized and merges with the expanded retainate flow 16 from the membrane module 1, which may be returned to the combustion stack.

[0074] Permeate flow 18d, dispensed from a further membrane cartridge 9a, merges with permeate flow 18a, dispensed from the first permeate outlet 17a, which is then compressed and transported. Permeate flow 18d contains a different carbon dioxide concentration compared to permeate flow 18a, dispensed from the first permeate outlet 17a. Depending on the mixing ratio of permeate flows 18a and 18d, permeate flows with predefined carbon dioxide concentrations can be generated.

[0075] System 30 includes a recycle line 35, which is adapted to guide a permeate flow 18c dispensed from a third permeate outlet 17c of the membrane module 1, either directly prior to the fluid inlet 13 of the membrane module 1 or prior to the inlet compressor 31. The recycle line may optionally include a recycle compressor 36, which is adapted to compress the permeate flow 18c to an operating pressure.

Claims

1. A membrane module for separating a fluid supply flow (14) comprising a permeable material and a retainate material into permeable flows (18, 18a, 18b, 18c, 18d) and retainate flows (16, 16a), The membrane module (1) is adapted for large-scale capture of carbon dioxide from industrial combustion exhaust gas emissions in cement plants, steel plants, and coal-fired power plants and waste-to-energy plants, etc. The membrane module is configured to operate within a pressure range of 100 kPa to 1.5 MPa for the fluid supply flow (14). The aforementioned membrane module is A pressure vessel (2) having a cylindrical wall (7) that extends along a vertical axis (4) from a first end (5) toward a second end (6) and encloses an internal space (8). Equipped with, The first end (5) of the pressure vessel (2) is closed by a first end cap (11), and the second end (6) of the pressure vessel (2) is closed by a second end cap (12). At least one of the first end cap (11) and the cylindrical side wall (7) is provided with a fluid inlet (13) for receiving the fluid supply flow (14), The second end cap (12) is provided with a retainate outlet (15) for discharging the retainate flow (16, 16a), At least one of the first end cap (11) and the second end cap (12) is provided with one or more permeate outlets (17, 17a, 17b, 17c) for discharging the permeate flow (18, 18a, 18b, 18c, 18d), The membrane module (1, 1') further comprises at least one membrane cartridge (9, 9a) arranged inside the pressure vessel (2), and each membrane cartridge (9, 9a) is A plurality of membrane envelopes (24) arranged in a stack configuration, Each of the membrane envelopes (24) comprises two membranes (25) each arranged on a carrier material, and one or more first spacers (26) between the membranes (25), the one or more first spacers (26) keeping the membranes (25) separated from each other in order to allow a free flow cross-section for the permeate flow (18, 18a, 18b, 18c, 18d) through the membrane envelope (24). The membrane (25) has an edge, and along the edge, the membrane (25) of the membrane envelope (24) is connected to a plurality of membrane envelopes (24) to prevent the fluid supply flow (14) and the retainate flow (16, 16a) from permeating into the membrane envelope (24). A second spacer (27) between the membrane envelopes (24) keeps the membrane envelopes (24) spaced apart in order to allow a free flow cross-section for the permeate flow of the fluid supply flow (14) and / or the retainate flow (16, 16a) in the flow direction, One or more permeate tubes (19) extending laterally with respect to the flow direction of the fluid supply flow (14) and fluidly connected to at least one permeate outlet (17, 17a, 17b, 17c), wherein the one or more permeate tubes (19) are provided with one or more radial openings, and the permeate material from the membrane envelope (24) arrives in the one or more permeate tubes (19) through the one or more radial openings. Equipped with, The at least one membrane cartridge (9, 9a) has a rectangular parallelepiped housing (10), Each pressure vessel (2) is provided with an annular body (20) positioned radially inward between the cylindrical wall (7) of the pressure vessel (2) and the rectangular parallelepiped housing (10) of the at least one membrane cartridge (9, 9a), The fluid inlet (13) is fluidly connected to the annular body (20) such that the pressure in the fluid inlet (13) and the annular body (20) are equalized. A membrane module characterized by the following features.

2. The membrane module according to claim 1, characterized in that the membrane module (1, 1') is configured to operate in a pressure range of 150 kPa to 1.0 MPa for the fluid supply flow (14).

3. The membrane module according to any one of the claims, wherein the pressure vessel (2) further comprises a first end piece (21) and a second end piece (22), each of which seals the at least one membrane cartridge (9, 9a) to the first end cap (11) and the second end cap (12), respectively.

4. The membrane module according to claim 3, characterized in that the first end piece (21) comprises an equalization port (23) configured to fluidly connect the fluid inlet (13) and the annular body (20) at the first end cap (11) such that the pressures at the fluid inlet (13) and the annular body (20) are equalized.

5. The membrane module (1, 1') comprises a plurality of membrane cartridges (9, 9a) arranged in series inside the pressure vessel (2) along the vertical axis (4), The rectangular parallelepiped housings (10) of the membrane cartridges (9, 9a) are sealed to each other so that the fluid supply flow (14) flows through the plurality of membrane cartridges (9, 9a) before exiting the membrane module (1, 1') as retained flow (16). A membrane module according to any of the above claims, characterized by the above.

6. A membrane module according to any one of the claims, characterized in that up to 12 membrane cartridges (9, 9a), preferably up to 10 membrane cartridges (9, 9a), more preferably up to 8 membrane cartridges (9, 9a), and most preferably 4 membrane cartridges (9, 9a) are arranged in series inside the pressure vessel (2).

7. The membrane module according to any one of the claims, characterized in that the pressure vessel (2) is provided with a removal mechanism that allows the removal of at least one membrane cartridge (9, 9a) from the pressure vessel (2) in accordance with its operation.

8. The membrane module according to claim 7, wherein the removal mechanism comprises rails arranged inside the pressure vessel (2) parallel to the vertical axis (4) of the pressure vessel (2), and the at least one membrane cartridge (9, 9a) comprises a pulley configured to roll on the rails so that the at least one membrane cartridge (9, 9a) can move out of the pressure vessel (2) along the rails.

9. The membrane module according to any one of claims 1 to 3 and 5 to 8, characterized in that the membrane cartridges (9, 9a) are arranged in two cartridge rows (28), each cartridge row (28) comprises a plurality of membrane cartridges (9, 9a) arranged in series, and the two cartridge rows (28) are arranged in parallel such that the fluid supply flow (14) flows simultaneously through both cartridge rows (28).

10. The membrane module according to claim 9, characterized in that the two cartridge rows (28) are arranged along the longitudinal axis (4) with a gap (29) between the two cartridge rows (28), the fluid inlet (13) at the first end cap (11) or the cylindrical side wall (4) of the pressure vessel (2) is fluidly connected to the gap (29) between the two cartridge rows (28), and the two cartridge rows (28) are further arranged such that the fluid supply flow (14) is divided in the gap (29) and flows in opposite directions along the longitudinal axis (4) through both cartridge rows (28) toward the first end cap (11) and the second end cap (12), respectively.

11. The membrane module according to any one of the claims, wherein the membrane module (1, 1') comprises a plurality of pressure vessels (2), preferably up to 10 pressure vessels (2), more preferably up to 6 pressure vessels (2), most preferably 4 pressure vessels (2), and further comprises an ISO standard and derivative multiple transport means compatible shipping container (3) of 20 feet, 40 feet, 45 feet high cube, 45 feet pallet wide, or 53 feet high cube in which the pressure vessels (2) are housed.

12. A method for separating a fluid supply flow (14) comprising a permeable material and a retainate material into permeable flows (18, 18a, 18b, 18c, 18d) and retainate flows (16, 16a), f. A membrane module (1, 1') according to any one of claims 1 to 11 is provided, g. The fluid supply flow (14) is guided into the at least one pressure vessel (2) through the fluid inlet (13), h. The fluid supply flow (14) flows through the at least one membrane cartridge (9, 9a) inside the pressure vessel (2) toward the retainate outlet (15), and during the permeate flow through the at least one membrane cartridge (9, 9a), the permeate material flows through the membrane (25) into the membrane envelope (24), thereby separating the fluid supply flow (14) into permeate flows (18, 18a, 18b, 18c, 18d) within the membrane envelope (24) and retainate flows (16, 16a) between the membrane envelope (24). i. The permeate flow (18, 18a, 18b, 18c, 18d) flows from the membrane envelope (25) through one or more radial openings into one or more permeate tubes (19), flows through one or more permeate tubes (19) to one or more permeate outlets (17, 17a, 17b, 17c), and is discharged there. j. When the retainate flow (16, 16a) flows between the membrane envelope (24) and passes through the at least one membrane cartridge (9, 9a), it is discharged through the retainate outlet (15). Each pressure vessel (2) includes an annular body (20) positioned radially inward between the cylindrical wall (7) of the pressure vessel (2) and the rectangular parallelepiped housing (10) of the at least one membrane cartridge (9, 9a), The fluid inlet (13) is fluidly connected to the annular body (20), A method comprising: the fluid supply flow (14) entering the at least one pressure vessel (2) partially flowing toward the annular body, thereby equalizing the pressure at the fluid inlet (13) and the annular body (20).

13. The method according to claim 12, wherein the membrane module (1, 1') comprises a plurality of membrane cartridges (9, 9a) arranged in series inside the pressure vessel (2) along the vertical axis (4), and in step e, the retainate flow (16, 16a) flows from between the membrane envelopes (24) to the subsequent membrane cartridges (9, 9a) of the plurality of membrane cartridges (9, 9a) arranged in series, and enters the subsequent membrane cartridges (9, 9a) as a fluid supply flow (14) after being removed, and the retainate flow (16, 16a) passes through the membrane cartridges (9, 9a) arranged in series and is discharged through the retainate outlet (15).

14. The method according to claim 12 or 13, wherein the fluid supply flow (14) and the permeate flows (18, 18a, 18b, 18c, 18d) flow through the at least one membrane cartridge (9, 9a) at least partially in a counterflow manner, passing each other.

15. The method according to any one of claims 12 to 14, wherein the pressure vessel (2) further comprises a first end piece (21) and a second end piece (22), each of which seals the at least one membrane cartridge (9, 9a) to the first end cap (11) and the second end cap (12), respectively.

16. The method according to any one of claims 12 to 15, wherein the first end piece (21) comprises an equalization port (23) configured to fluidly connect the fluid inlet (13) and the annular body (20) in the first end cap (11).

17. The method according to any one of claims 12 to 16, wherein the fluid supply flow (14) has a pressure range of 100 kPa to 2 MPa, preferably 100 kPa to 1.5 MPa, and more preferably 150 kPa to 1.0 MPa.

18. The method according to any one of claims 12 to 17, wherein the membrane cartridges (9, 9a) are arranged in two cartridge rows (28) with a gap (29) between the two cartridge rows (28), each cartridge row (28) comprises a plurality of membrane cartridges (9, 9a) arranged in series, the two cartridge rows (28) are arranged in parallel, and the fluid supply flow (14) flows simultaneously through both of the cartridge rows (28) in opposite directions along the longitudinal axis (4) from the gap (29) through both of the cartridge rows (28) toward the first end cap (11) and the second end cap (12), respectively.

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