NL2037461B1

NL2037461B1 - Sorption module for CO2 sorption

Info

Publication number: NL2037461B1
Application number: NL2037461A
Authority: NL
Inventors: Jacobus Jenneskens Rob; De Roest Arne
Original assignee: Carbyon Holding B V
Priority date: 2024-03-29
Filing date: 2024-04-15
Publication date: 2025-10-06

Abstract

-19- The invention relates to a sorption module for COz sorption, comprising: - a porous and tubular sorbent, for sorbing C02 in a first state, and for desorbing sorbed COz from the sorbent in a second state; - a first and a second support, connected to and supporting the sorbent at opposing spaced apart ends of the sorbent, supporting a central part of the sorbent extending between the first and second support through respective end parts of the sorbent abutting against the first and second support, which sorption module is configured for allowing a gaseous composition comprising 002, such as ambient air, to flow between an interior and an exterior through the tubular sorbent.

Description

Sorption module for CO: sorption

The invention relates to a sorption module for CO: sorption.

CO: or carbon dioxide is a chemical compound which is released by the combustion of fossil fuels.

There is a desire to reduce the footprint of human mankind to the amount of CO: released into the atmosphere, because it is generally accepted that the increased concentration of CO: in ambient air causes climate change. CO: may be captured from exhaust streams of industrial processes. However, due to the already increased CO: concentration in the air since the start of the Industrial Revolution, there is also an interest to remove CO: from ambient air. Processes which are aimed to capture CO: directly from ambient air are also referred to as Direct Air Capture (DAC) processes.

Capture processes typically involve a plurality of alternating sorption and desorption steps, which may be carried out in a cyclical manner. In the adsorption step, a sorbent capable of binding COz, which is contained in a reactor, is contacted with a gaseous composition (which is air, in the case of DAC).

This causes at least a part of the CO: in the gaseous composition to be sorbed by the sorbent and the

CO: concentration in the gaseous composition to be reduced at the outlet relative to the concentration at the inlet. During the subsequent desorption step, the conditions within the reactor are changed (e.g. by closure of the reactor and/or the application of heat and/or a reduction in pressure) in order to release the sorbed CO2, which may be used for various purposes (e.g. chemical conversion or storage).

Despite all the efforts in decreasing the level of CO: in air over the past decades, the CO2 concentration in air has even increased to a current level of approximately 424 ppm. In other words, current technologies fail to achieve sufficient reduction to reverse climate change.

WO 2023/287630 (Decarbontek LLC) discloses an adsorbent device which includes adsorbent fibers that are either laid parallel to or wound around a center tube. The device may also comprise a heating element to regenerate the adsorbent fibers.

WO 92/05860 (Keith Landy) discloses a gas filtering unit including sheet(s) of flexible, coilable, permeable, carbon impregnated fabric that are spirally wound around a center structure, also therein referred to as a central manifold, which is blocked at one end.

US 11524258 (Aura Mat Inc) discloses an adsorbent material module which includes a plurality of tubular adsorbent materials and a plurality of medium materials. Each of the tubular adsorbent materials includes at least one channel and at least one adsorbent layer. The adsorbent layer surrounds the at least one channel. The medium materials are coated on two ends of each of the tubular adsorbent materials, respectively, and the medium materials have a thermal conductivity function or an electrical conductivity function.

WO 2014/170184 (Climeworks AG) discloses a separation unit for the separation of a first gas, preferably carbon dioxide, from a mixture containing said first gas as well as further gases different from the first gas, preferably air, is proposed, for use in a cyclic sorption/desorption process and using a loose particulate sorbent material for gas sorption. In the unit, particulate sorbent material is arranged in at least two stacked layers, and each layer comprises two sheets of a flexible fabric material which is gas permeable but impermeable to the loose particulate sorbent material.

It is an object of the invention to alleviate or even obviate the above-mentioned disadvantages, and more specifically to provide a sorption module with an decreased costs, in terms of operational costs (e.g. efficiency) and/or cost of manufacture.

This object is achieved with a sorption module for CO: sorption, comprising: - a porous and tubular sorbent for sorbing CO: in a first state, and for desorbing sorbed CO: from the sorbent in a second state; - a first and a second support, connected to and supporting the sorbent at opposing, preferably spaced apart, ends of the sorbent, supporting a central part of the sorbent extending between the first and second support, preferably through respective end parts of the sorbent abutting against the first and second support, which sorption module is configured for allowing a gaseous composition comprising

CO, such as ambient air, to flow between an interior and an exterior through the tubular sorbent.

It has surprisingly been found that the provision of such a sorption module provides enhanced flexibility in designing the sorption module due to a provision of both a first and a second support, which may be designed in different ways. In some cases, the first and second support may for instance be integral. However, in a particularly preferred case, the first and second support are connected to, and are supporting the sorbent at spaced apart ends of the sorbent (which implies that the first and second support are spaced apart from each other). The thickness of the sorbent, the length of the central part and the length of the end parts are chosen such that the connection of the sorbent with its end parts to the first and second support provides for sufficient support for the central part as well, which includes ensuring that the central part remains its shape when used, e.g. when applying a flow of the gaseous composition through it. Such a sorption module does not require the support to extend between the first and the second support and will consequently have a smaller dead mass (i.e. the thermal mass of sorbent not contributing to the sorption of CO2), in contrast to the sorption modules disclosed in e.g. WO 2023/287630, WO 2014/170184 and WO 92/05860. A sorption module which is connected to the first and second support may imply that the first and second support are enclosed by the sorbent.

A tubular sorbent may mean that is the sorbent is substantially axisymmetric, such as cylindrical or frustoconical. Cylindrical or frustoconical sorbents have the advantage of being self-supporting by themselves. In such a case, the dimensions of the first and second support are chosen to keep the cross-section over its full length between the first end second support of the sorbent cylindrical (or frustroconical). Additionally and/or alternatively, a tubular sorbent (which is hollow) may be oval, such as circular in cross-section, preferably over the full gh of the sorbent). Any of the sorption modules according to the invention may have a module axis. When such a sorption module has a module axis, the sorbent may be wound around said module axis for forming a circumferential wall around said module axis. Such a tubular axisymmetric sorbent may be substantially axisymmetric with respect to said module axis.

The sorbent is able bind CO: in a first state (i.e. a set of conditions, e.g. temperature, pressure, humidity, electrochemical state or any combination of at least one of these}, and to release CO2 bound to it in a second state in which at least one or any combination of said conditions is different.

By allowing a gaseous composition to flow between an interior and an exterior through the sorbent (that is, either from the interior, through the sorbent and thereafter to the exterior, or vice versa), the sorbent is able to capture or sorb CO: from the gaseous composition, thereby reducing the concentration of CO: at an output of the sorption module with respect to the input. Sorption will typically mainly involve adsorption. The gaseous composition is most preferably (ambient) air, which implies that the sorption module is used for Direct Air Capture (DAC).

In a preferred embodiment of the sorption module, an inlet to the sorption module is provided in the first support, and the sorbent is gas permeable, i.e. having a plurality of pores formed in the material wherethrough the gas may flow from the interior to the exterior and vice versa, thereby forming an outlet of the sorption module. The provision of an inlet in the first support allows the gaseous composition to enter the interior of the sorption module, and allows the gaseous composition to conveniently pass through the sorbent, to reduce the concentration of CO: relative to the concentration at the inlet. This in contrast to the design according to the flow-along cartridges according to US 11524258, in which the adsorbent materials 110 are densely packed, thereby leaving limited to no space for flow of a gaseous composition throughout the adsorbent material. If the module has a module axis, a plane through the inlet is preferably substantially perpendicular to the module axis.

Since the first and second supports will support the end parts of the sorbent, the gaseous composition will substantially pass through the central part of the sorbent that is in between the respective end parts. The passage of the gaseous composition through the sorbent causes the sorbent {or specifically: the outer boundary or outer surface thereof, or even more specifically: a plurality of pores therein and/or an internal pore structure thereof) to form the outlet of the sorption module. In order to ensure that the gaseous composition will pass through the sorbent, the second support is preferably closed, which means that the gaseous composition which has entered the sorption module through the first support is unable to leave the interior through the second support at the other longitudinal end and/or at the other end of the module axis of the sorption module.

In another preferred embodiment of the sorption module, the sorbent comprises a plurality of layers arranged on top of each other, wherein the sorbent is preferably formed from a single sheet, which sheet is at least partially wound onto itself. By having a sorbent which comprises a plurality of layers arranged on top of each other, it is easier to build a sorption module with suitable dimensions based on the process needs. For instance, when increasing the length of the central part of the sorbent, the sorbent will typically require a larger thickness for the first and second support to adequately support all of the sorbent over its full length, while most typically only being supported by the first and second support through its end parts. The plurality of layers will typically be chosen to achieve a sorbent with a total thickness of between 2 and 30 millimetres, preferably between 8 and 12 millimetres. It is advantageous to use layers with a thickness of between 0.5 and 3 millimetres, preferably between 1.0 and 2.5 millimetres, in particular when the thickness is low, or in case of a varying (e.g. increasing) thickness along its length. If the sorbent is built-up from a single sheet, the mechanical stability of the sorption module increases compared to sorption modules which is built-up from a plurality of separate sheets.

In a preferred embodiment of the sorption module, the sorbent is thermoresponsive. A thermoresponsive sorbent is a sorbent which is able to release CO2 bound to it by the application of inputted thermal energy to it, either indirectly (i.e. via another medium, of which the temperature is increased, which is in heat-exchanging contact with the sorbent) or directly (i.e. the energy causes the sorbent itself, or at least a part thereof, to increase in temperature without necessarily heating a medium other than the sorbent). This means that the change of the sorbent between the first state and the second state at least implies a change of temperature. In other words, the sorbent is responsive to inputted energy for heating the sorbent to a temperature for desorbing sorbed CO: from the sorbent.

If the sorption module according to this embodiment does not have a support extending between the first and the second support, the thermal mass will be relatively small, requiring less thermal energy to and heat the sorbent for desorbing sorbed CO:2.

In another embodiment of the sorption module, the sorption module comprises connecting means, for electrically and/or thermally connecting the sorbent to an energy source for providing energy to the sorbent, preferably at least arranged at or near the end parts of the sorbent. The connecting means may also be referred to as at least one connecting element. The connecting means may be arranged such that, when connected to the energy source, a current and/or a heat flow flows through the sorbent, preferably from substantially one end part of the sorbent to the other, in particular when the sorbent is thermoresponsive. When the energy is supplied to the sorbent as a cutrent, this current will preferably cause the sorbent to increase in temperature by Joule heating.

When the sorbent is thermoresponsive, the sorption module may alternatively or additionally, comprise heating means to heat the sorbent, which may also referred to as at least one heating element, which may increase in temperature. Such a heating means will be in heat exchanging contact with the sorbent, causing the temperature of the sorbent to increase as well. The heating means may for instance be an (insulated) electrical resistance wire. In order to provide energy to the heating means, these may be connected to the connecting means.

In general, provision at or near the end parts of the connecting means would preferably mean a position in which the central part is left free from connecting means. Such a position would on one hand ensure that the condition applied onto the sorption module {e.g. temperature increase, in case of a thermoresponsive sorbent) is effectuated across most of the length of the sorbent, while on the other hand maximizing permeation of the gaseous composition through the sorbent.

Ina preferred embodiment of the sorption module, the connecting means comprise at least one of: - a conductive layer, preferably a metal layer, wherein the conductive layer preferably comprises one and, more preferably, two, continuous strips of said material, arranged between at least some, preferably a majority and preferably all, of the sorbent layers and/or on top of the outer sorbent layer; and - an amount of thermally and/or electrically conductive solder or paste.

By providing a conductive layer, it may be possible to connect an energy source to the sorbent in such a way that it will change from the first state to the second state (e.g. increase in temperature when inputting energy to it), and most typically, that this effect will be homogeneous across the sorbent. It is advantageous to provide the layer between a plurality or even all of the sorbent layers in order to increase the connection of the sorbent with the energy source and hence the homogeneity of the effect of the sorbent as a consequence of the input of energy to it. The thickness of the conductive layer with respective to the thickness and the deformability of the sorbent layers, possibly combined with the method of winding these sorbent layers are preferably chosen such that subsequent layers of sorbent are still in physical contact with each other along their length, which may be parallel to a module axis, in spite of the conductive layer which is arranged between subsequent layers of sorbent material. To achieve this, the thickness of the conductive layer may be at least 5 times smaller than the thickness of the sorbent layer, preferably at least 10 times smaller than the thickness of the sorbent layer, more preferably at least 20 times smaller than the thickness of the sorbent layer, most preferably at least 30 times smaller than the thickness of the sorbent layer. Additionally or alternatively, one sorbent layer or the conductive layer may be deformed (e.g. compressed onto an adjacent sorbent layer and/or conductive layer) to achieve this effect.

In another embodiment of the sorption module, the sorption module further comprises at least one fastening means for fastening the sorbent to the first and second support and/or the plurality of layers of the sorbent to each other.

In order to increase the mechanical stability of the sorption module, it is highly recommended to fasten {or equivalently: fix or otherwise secure) sorbent layers to each other and/or the sorbent to the first and second support, since this will increase the lifetime of the sorption module, in particular in a situation where the desorption of sorbed CO: from the sorbent involves the application of a pressure to the sorption module. The fastening means may also be referred to as at least one fastening element.

One particular embodiment of such fastening means may be a wire and/or a wrap, wound around the sorbent in a path between the first and the second support, preferably running from the first support to the second support (i.e. the entire central part), although the path may alternatively cover just a part of the central part. Such a path is not limited to a particular design, but in order to achieve the effect with as little material as possible, thereby contributing to a reduction in dead mass, and with as little reduction of the central part of the sorbent, a helical path would be preferred.

Another particular embodiment of such fastening means may be a clamping means, such as at least one of an either plastically deformable and/or resilient (i.e. elastically deformable) arm with a first end fixed to at least one of the first and second support and an opposing free end, abutting against an exterior of the sorbent, forcing one of the end parts of the sorbent towards said support. The clamping means may also be referred to as at least one clamping element. Such a clamping element provides a simple way of securing the sorbent layers to each other and/or to the first and second support, while having a relatively low impact on the surface of the sorbent layer accessible to the gaseous composition when passing through the sorbent.

In a preferred embodiment of the sorption module, the sorbent comprises a plurality of fibres formed into a fabric, such as a felt or a woven textile material. In between the plurality of the fibres of the fabric, the sorbent will have a volume in which the gaseous composition is allowed to reach and/or contact to the plurality of fibres. This allows fibrous sorbents to have a relatively high surface area for the sorption process. Due to this volume, which typically extends throughout a layer of the fabric, the gaseous composition is able to travel throughout the fabric, which makes it possible for the fabric to be used for permeating from the interior of the sorption module to the exterior of the module, without requiring complex modifications to the sorption module to ensure this. Furthermore, such fabrics such as felts are easily used in a sorption module in which the sorbent is built-up from a plurality of layers, and a conductive layer may be easily affixed to such supports. Also, these fabrics are easily fastened to each other and/or to the first and second support. Fabrics such as felts are typically also deformable which allows them to accommodate a conductive layer such as a metal tape between layers of the sorbent, while keeping the subsequent layers in physical contact with each other.

In another embodiment of the sorption module, the sorbent comprises a) a carrier with an internal pore structure and b) an active ingredient capable of sorbing COz, provided within the internal pore structure.

The provision of a sorbent which has an internal pore structure further increases the surface area of the sorbent. The active ingredient will sorb the majority of the COa, since the active ingredient typically has a higher affinity and/or capacity for CO2 compared to the carrier. The sorbent is responsive to a change from the first to the second state for releasing sorbed CO: and may for instance be at least thermoresponsive.

Suitable carriers may for instance be carbonaceous carriers such as active carbon, which may be used as a granulate or a powder, or as a fibrous fabric, eh as a felt. In case of such a fabric, apart from the volume provided between the fibres of the fabric, the fibres itself are preferably also porous (having an internal pore structure). Suitable active ingredients may for instance be alkali metal or alkaline earth metal carbonates, such as potassium carbonate or sodium carbonate, amine-based active ingredients metal organic frameworks. A carbonate active ingredient, such as potassium carbonate, is typically combined with a granulate or felt of active carbon.

In an embodiment of the sorption module, at least one of an inner diameter and an outer diameter of one of the end parts is equal to the same of the inner diameter and the outer diameter of the other of the end parts, and wherein preferably the respective inner or outer diameter is constant between the end parts. The inner and cuter diameter is a main dimension of the end parts. When the module has a module axis, the inner and/or the outer diameter is typically perpendicular to the module axis. When one or both of these diameters are equal at both end parts, this simplifies the design of the sorption module and increases the stability of the sorption module. When said diameter(s) are even constant between the end parts (thus along the module axis), this makes the module easier to manufacture, in particular when the sorption module is built from a sorbent with a plurality of sorbent layers, such as a fibrous fabric, e.g. a felt.

In another embodiment of the sorption module, a thickness of the sorbent between the first and second support is constant. When the thickness, i.e. the thickness of the circumferential wall around the module axis forming the tubular sorbent, where applicable, is constant between the first and the second support, this may simplify the construction of the sorption module.

Alternatively, in an embodiment of the sorption module, a thickness of the sorbent increases gradually from the first support towards the second support. It may be advantageous if the sorbent gradually increases from the first support (which typically contains the inlet) towards the second support (which is typically closed, in order to force the gaseous composition from the interior throughout the sorbent).

For sorption modules in which the thickness of the sorbent is equal along its length, it has surprisingly been observed that the amount of the gaseous composition passed through the sorbent increases along its length when moving from the first to the second support. In some cases, it may thus be provided to have the thickness of the sorbent increase gradually from the first support {through which the gaseous composition enters the sorption module} towards the (typically closed) second support. In this way, flow resistance is increasingly added towards the second support, in order to equalize the flow along the length. The increase is preferably chosen to have each amount (e.g. weight) of sorbent along the length to be exposed to the same amount of CO2 during sorption on average.

In another embodiment of the sorption module, the thermal mass ratio (i.e. the product of its mass and the specific heat capacity) between a) the first and second support together with the directly thereagainst abutting end parts of the sorbent, and b} the central part of the sorbent, is from 0.001 to 0.50, preferably 0.005 to 0.30, more preferably from 0.01 to 0.15, most preferably from 0.01 to 0.05, wherein the ratio is determined by the ratio of a) over b). With such thermal mass ratios, most of the thermal mass of the sorption module is used or the actual sorption of CO: from the gaseous composition, and the other parts, which will have a much less substantive contribution to the sorption, have a relatively low thermal mass. This makes the sorption module more efficient in use: typical desorption processes use heat to desorb CO: from the sorption module, and in this way, most of the energy inputted is used for actually desorbing CO2. When the sorbent of the sorption module comprises a plurality of layers, all of the layers which are arranged on top of a layer abutting against the support may be part of the part of the sorbent referred to as a) as well.

In an embodiment of the sorption module, at least one of the first and the second support comprises a sealing member, for sealing the sorption module to an opening in a wall in a gastight manner. With such a sealing member, it is ensured that most of the gaseous composition will pass through the sorbent. In this sense, a gastight connection may mean that the permeation through said sealing member is at least 50 times, preferably at least 100 times, more preferably at least 500 times, most preferably at least 1000 times lower than through the central part of the sorbent.

While it is in some embodiments possible to have a sealing member which comprises at least one screw, a bayonet connection, glue, a frictional sealing and/or thermal bonding, in a preferred embodiment of the sorption module, the sealing member additionally and/or alternatively comprises a, preferably resilient, connector connected to an end of at least one of the first and second support that is opposite to the sorbent, which is preferably arranged around the circumference of said first or second support, and is configured for being introduced into the opening in the wall. Resilient connectors provide both the advantage of a stable and simple connection which is nevertheless relatively simple to disconnect, for instance in case maintenance is needed to the sorption module. A connector may be arranged on one end (e.g. in the end containing the inlet, e.g. the first support) or a connector may be arranged at both opposing longitudinal ends. By providing the connector around the circumference of the support(s), the stability of the connection is increased, which is beneficial since the use of the sorption module may involve the exertion of a pressure on the module.

In an embodiment of the sorption module, the sealing member is suitable for thermally and/or electrically decoupling the wall from the sorbent, wherein the sealing member preferably has a thermal conductivity of at most 3 W/K, more preferably at most 0.3 W/K, most preferably at most 0.03 W/K and/or is electrically non-conductive. By thermally decoupling the wall from the sorbent, itis less likely that energy inputted into the sorption module, e.g. for desorbing CO: from the sorption module, is conducted away from the sorbent, which ensures a more efficient operation of the sorption module. Examples which are suitable for thermally decoupling the wall from the sorbent may be plastics or ceramics. By electrically decoupling the wall from the sorbent, the inputted electrical energy through the connecting means is less likely to leak away through the wall, again increasing the efficiency of the sorption module. Non- conductive may in particular mean that the electrical resistance through the sealing member is at least 10 times, preferably at least 20 times, more preferably at least 50 times, most preferably at least 100 times higher than the resistance of the sorbent. 3

In an embodiment of the sorption module, the ratio between a) the length of the end parts the sorbent and b) the length of the central part of the sorbent is at most 0.20, more preferably at most 0.10, most preferably at most 0.05, as determined by a) over b). By thus choosing the length of the central part with respect to the end parts supported by the first and second support as such, it is ensured that the first and second support provide sufficient support to the sorbent at a minimum contact surface between the first and second support on the one hand, and the sorbent on the other hand.

Any of the sorption modules as described herein may also be used for building a sorption cartridge. The invention thus also relates to a sorption cartridge, comprising: - a housing comprising a sorption module receiving section, and - at least one sorption module according to any one of the preceding claims and/or embodiments, received (e.g. fixed) in the sorption module receiving section.

The provision of a sorption cartridge which contains the sorption cartridge provides a suitable way of arranging the sorption in a sorption reactor, e.g. a DAC machine. When providing more than one sorption module per sorption cartridge, this will lead to an increase in capacity. Since the cartridge is typically replaceable from the sorption reactor as a single unit, it is easy to swap a relatively large amount of capacity in a single act. The sorption cartridge may for instance have between 2 and 200 sorption modules, preferably between 5 and 100 sorption modules, more preferably between 10 and 80 sorption modules, most preferably between 30 and 60 sorption modules. Additionally and/or alternatively, the sorption cartridge has a weight allowing it to be transported by one human, preferably without requiring additional industrial machinery, thereby increasing the ease of maintenance. The sorption modules within the sorption cartridge are typically not in physical contact with each other, apart from their connection to the common housing, in order to achieve a suitable air flow between the sorption modules within the sorption cartridge.

In an embodiment of the sorption cartridge, the housing comprises at least one wall, preferably two spaced apart walls, and the sorption module receiving section comprises at least one, preferably more than one, opening in at least one of the at least one wall, preferably more than one opening in each of the respective walls, and the at least one sorption module is received in at least one of the at least one opening in the wall, or the walls. Where applicable, the sorption module is preferably received in the sorption module receiving section with its sealing means. The wall or walls of the cartridge will retain and/or hold the longitudinal ends of the cartridge, thereby increasing the ease of handling. By providing more than one opening in each of the walls, more than one sorption module can be arranged between the walls of the sorption cartridge. For ease of construction, it is highly recommended that all of the sorption modules within a sorption cartridge are oriented substantially parallel to each other, e.g. with their module axes substantially parallel to each other. While both walls may have a sorption module receiving section for receiving one of the first and the second support respectively, one of these sections {or openings), i.e. the one receiving the end of the sorption module comprising the inlet, typically the first support, also serves as a means to niroduce a gaseous composition into the cartridge, whereas the other only serves to hold the sorption module in place, since the sorption module is typically closed at the end near the second support, which may be embodied as a closed hole and/or recess, with the gaseous composition exiting the sorption module by passing throughout the porous sorbent.

In an embodiment of the sorption cartridge, the sorption cartridge further comprises a circumferential wall, extending between the two spaced apart walls. The provision of a circumferential wall, which shields the sorption module(s) within the sorption cartridge from the outside ensures that should heat be generated within the sorption cartridge, this will be more likely to remain within the sorption cartridge, increasing process efficiency (in particular when the sorbent is thermoresponsive), and that the collection of gaseous composition from the sorption cartridge is easier. The circumferential wall may however comprise some openings, either in one or both of the walls and/or in the circumferential wall to provide for the attachments of cables to the sorption module(s), e.g. for inputting energy to the sorption module(s) and/or for collecting gaseous composition from the output of the sorption module(s) in the sorption cartridge.

In an embodiment of the sorption cartridge, at least a part of the interior of the housing is reflective.

When the interior of the housing (e.g. the sides of one or both of the walls and/or the circumferential wall facing the sorption module(s) within the sorption cartridge) is reflective, any heat inside the cartridge is even less likely to escape from the sorption cartridge, increasing process efficiency (in particular for a thermoresponsive sorbent).

In an embodiment of the sorption cartridge, the sorption module receiving section, preferably the at least one opening in the at least one wall, is configured for axially and radially locking the sorption module at one end thereof, and wherein the sorption module receiving section, preferably the at least one opening in the other wall, is configured for radially locking the sorption module, while allowing axial movement along a length less than the length of one sealing member. By axially and radially locking the sorption module at one end (in one of the walls) and by allowing for axial movement while radially locking the module at the other end (in the other wall), the sorption module is well secured to the sorption cartridge, while allowing for adjustments, e.g. for when removing one of the sorption modules from the sorption cartridge.

The invention also relates to a method for producing a sorption module as described herein, comprising the steps of: a) providing a first and a second support at spaced apart holding positions; b) arranging a porous sorbent for sorbing CO: in a first state, and for desorbing sorbed CO: from the sorbent in a second state, onto the first and second support, and ¢) causing a relative movement between the first and second support and the sorbent such that the sorbent is wound around the first and second support, such that at least a section of the first support and a section of the second support are covered by the sorbent.

The relative movement of the first and second support on the one end and the sorbent on the other to each other causes the sorbent to be wound around said supports. This may involve a movement of the sorbent with respect to a stationary first and second support, a stationary sorbent with respect to a moving first and second support, or a combination of such movements in which neither of the sorbent and the first and second support is static relative to the environment. The first and second supports are preferably provided at positions {e.g. near ends) of a holding element, in which each of the first and second supports comprises a part abutting against and around the holding element to further ensure the stability of the production process. The first and second support preferably each comprise a circumferential flange, which are substantially in line with each other, and most typically, in step b) the sorbent is only arranged along a part of this circumferential flange, and step c) will cause the sorbent to be arranged around at least the entire circumferential flange.

The sorbent is able bind CO: in a first state (i.e. a set of conditions, e.g. temperature, pressure, humidity, electrochemical state or any combination of at least one of these), and to release CO: bound to it in a second state in which at least one or any combination of said conditions is different. The sorbent may for instance be at least thermoresponsive.

In a preferred embodiment of the method, in step a) the first and second support are arranged onto a spindle. The provision of a spindle is a convenient way of causing relative movement of the first and second support with respect to the sorbent, while keeping the first and second support at a fixed position with respect to each other. After completing the method, the spindle is removed, which results in the sorption module.

In another embodiment of the method, the relative movement causes at least a part of the sorbent to be wound around itself for one or more than one turn. This is a convenient way of building a sorption module with a chosen thickness, regardless of the thickness of the sorbent (e.g. fibrous fabric such as felt) of which it is made. The first and last winding may in some embodiments start and/or end with a cut perpendicular to the sorbent being wound around the spindle. In other words, the start and end edge of the sorbent should be helical after winding. This may help to prevent a loose flap on at least one of an inner and outer diameter, and it may be used to increase uniformity of thickness along the circumference and/or increase uniformity of airflow (as the total pressure drop for a section further away from the air inlet is higher than that of a section close to the inlet).

In another embodiment of the method, the method further comprises the step of: d) arranging connecting means, for electrically and/or thermally connecting the sorbent to an energy source for providing energy to the sorbent, onto the porous sorbent at or near the first and the second support with the first and second support arranged in the holding positions.

The provision of connecting means during the process of manufacturing the sorption module increases the efficiency of the construction process. 2

In a preferred embodiment of the method, the sorbent is a felt, and wherein the connecting means is a conductive layer, such as a metal layer, wherein in step c) the relative movement causes the conductive layer to be wound between respective layers of the felt. In other words, the winding of the sorbent onto the first and second support at the same time causes the arrangement of the conductive layers between subsequent felt layers. The metal layer may for instance be a tape, which has an adhesive (e.g. a self- adhesive or a pressure and/or heat sensitive adhesive) attached to it for adhering it to the sorbent.

The sorption module and the sorption cartridge may be used for capturing CO: from air. In other words, the invention also relates to a method for collecting CO: from air, comprising the steps of: a) providing a sorption module according to the invention, or a sorption cartridge according to the invention, or a sorption module obtainable by a method according to the invention; b) arranging the first support of the sorption module downstream of a gas inlet and arranging the exterior of the sorbent of the sorption module upstream of a gas outlet; c) executing at least one sorption and desorption cycle, one sorption and desorption cycle comprising the steps of: c1) forcing air from the gas inlet through said sorption module to the gas outlet, thereby sorbing CO» from the air to the sorbent of the sorption module; c¢2) allowing an electric current to run through the sorbent for desorbing sorbed CO: from the sorbent; c3) collecting the CO: desorbed from the sorbent.

When the sorbent is thermoresponsive, the electric current may cause Joule heating of the sorbent to cause the desorption of the sorbed CO: from the sorbent.

In use, the gaseous composition will typically have a temperature of between -30 and 50 °C, although other {e.g. higher or lower) temperatures may also be possible if the temperature allows sorption to take place. This temperature will typically be below the desorption temperature in the subsequent desorption step. The sorption cartridge and sorption module as described herein are able to withstand such temperatures, which in particular may mean that the sorption cartridge and/or module would be able to operate for a plurality of cycles without significant degradation in capacity and/or performance.

Any feature described herein for the sorption module may also be embodied in a sorption cartridge for the same or similar reasons. Any feature described for the sorption module or the sorption cartridge may, for similar reasons, also be used in a method for making a sorption module. The method of making a sorption module may also involve several additional steps, such as the insertion of the sorption cartridge in one or two opposing walls and optionally the provision of a circumferential wall to build a sorption cartridge.

These and other features of the invention will be further elucidated alongside the following drawings.

Figure 1 is a perspective view of a sorption module according to the invention.

Figure 2 is a side view of the sorption module according to Figure 1.

Figure 3 is a cross-section of the sorption module along line III-lII in Figure 2.

Figure 4 is a perspective view of a sorption cartridge according to the invention.

Figure 5 is a top view of the sorption cartridge according to Figure 4.

Figure 6 is a cross-section of the sorption cartridge along line VI-VI in Figure 5.

Figure 7 shows a first embodiment of clamping means according to the invention.

Figure 8 shows a second embodiment of clamping means according to the invention.

Figure 9 shows a third embodiment of clamping means according to the invention.

Figure 10 shows a fourth embodiment of clamping means according to the invention.

Figure 11A and 11B show a fifth embodiment of clamping means according to the invention, in an open and closed configuration, respectively.

Figure 1 shows a sorption module 1 according to the invention. The sorption module 1 has a first support 2 and a second support 3, which are arranged at spaced apart ends of the sorption module 1.

Atubular porous (and thereby gas permeable) sorbent 4, having a circular cross section is supported by the first and second supports 2, 3. In Figure 1, the exterior of the sorbent 4 is shown. The first support 1 is provided with an inlet 5 to the sorption module, to allow a gaseous composition to enter the interior of the tubular sorbent. The second support 3 is closed, meaning that a gaseous composition cannot enter into the interior of the sorbent 4 through second support 3. Both the first support 2 and second support 3 have a circumferential flange 8, 7 for a purpose illustrated in relation to Figure 5. As shown the flanges 8, 7 are spaced apart from the sorbent 4 in order to at least thermally decouple the sorbent 4 from the flanges 6, 7.

Figure 2 shows the same sorption module 1. The sorption module 1 has a module axis 8. The first support 2 and second support 3 are each provided with respective connectors 9, 10 to connect the sorbent 4 to an energy source, in particular a source of electrical energy, suitable for inputting energy into the sorbent 4.

As can be seen from Figure 3, the first support 2 comprises inlet 5, while the second support 3 is closed, which implies that the porous sorbent 4, in particular the exterior thereof, is the outlet of the sorption module 1. The sorbent comprises a plurality of sorbent layers 11, 12, 13, which are constructed by winding a single sheet onto itself, thereby forming a cylindrical wall. The sorbent layers 11, 12, 13 are, at the end parts 14, 15 of the sorbent, provided with a continuous copper tape 16, adhered to the sorbent layers 11, 12, 13. In use, a gaseous composition will enter the sorption module 1 through inlet 5, and follow path 17 from the interior 22 of the sorbent 4 to the exterior 23. The end parts 14, 15 of the sorbent 4 are supported by the first and second support 2, 3, whereas a central part 18 is suspended between, and only supported through, the respective end parts 14, 15, which abut against the first and second supports 2, 3. Both the inner diameter 19 and the outer diameter 20 of the sorbent are constant between end parts 14, 15, as is the thickness 21. The length ratio of the part of the first and second support abutting against the substrate 14, 15 one the one end and the diameter 19 thereof is preferably small, e.g. at most 0.10, at most 0.05 or even at most 0.01.

Figure 4 and 5 show a sorption cartridge 50, comprising a housing 51 with a first walt 52, and an opposingly arranged second wall 53 and a circumferential wall 54 extending between the walls 52, 53.

The first and second wall 52, 53 comprise openings 55, into which sorption modules 80, like sorption module 1, are received in an orientation substantially parallel with respect to each other and the circumferential wall 54, and hence substantially perpendicular to the first wall 52 and second wall 53.

In this configuration, the inlet 5 of the sorption modules 80 are accessible from the exterior of the sorption cartridge 50 through respective openings 55. The circumferential wall 54 is provided with a slot 56, allowing cables, like electrical connections, to connect with connectors 9, 10.

As can be seen in Figure 3, the first support 2 comprises a supporting part 30, supporting the end part 14 of the sorbent, and a connecting part 31, for connecting the first support to the first wall 52.

Connecting part 31 is resilient in order to seal the first support 2 into the first wall 52. Similarly, the seconds support 3 comprises a supporting part 32, supporting the end part 15 of the sorbent, and a connecting part 33, for connecting the first support to the second walt 53. Connecting part 33 is resilient in order to seal the first support 3 into the second wall 53. The thermal mass ratio between a) the supports 2, 3 together with the part of the sorbent 4 extending along the end parts 14, 15, and b) the central part 18, is from 0.001 to 0.50, preferably 0.005 to 0.30, more preferably from 0.01 to 0.15, most preferably from 0.01 to 0.05.

As can be seen in Figure 6, the sorption modules 80 are arranged spaced apart from each other within the housing 51 of the sorption cartridge 50, leaving a volume 57 free through which a gaseous composition may pass after having passed from the inlet 5 and through the sorbent 4. The flanges 6, 7 of the sorption modules 80 abut against the first wall 52 and second wall 53 of the housing 51. The interior of the circumferential wall 54 (i.e. the side facing sorption modules 80) is reflective.

Various ways of clamping are illustrated in relation to Figures 7 to 11. In Figure 7, several layers of sorbent 70 are clamped between a support 71 (such as first support 2 and/or second support 3) and a separate clamping element 72, which are fixed to each other using a fixture 73, like a bolt. Support 71 and clamping element 72 may be connecting elements, connecting to metal tape 74, allowing an electrical current to be transmitted onto the sorbent 70.

In Figure 8, several layers of sorbent 88 are arranged between a support 81 (such as first support 2 and/or second support 3) and a spring element 82, forcing the layers of sorbent 88 onto the support 81. A clamping element 83 may further assist in keeping the layers 88 and the spring element 82 in a required position. Support 81 may be a connecting element, connecting to metal tape 84, allowing an electrical current to be transmitted onto the sorbent 88.

In Figure 9, several layers of sorbent 90 are arranged between a support 91 (such as first support 2 and/or second support 3) and a wrapping element 92, such as a fiber or tie-wrap, fixing the sorbent layers 90 to the support 91. Support 91 may be a connecting element, connecting to metal tape 93, allowing an electrical current to be transmitted onto the sorbent 90.

In Figure 10, several layers of sorbent 100 are fixed onto a support 101 (such as first support 2 and/or second support 3) by a volume of solder 102, fixing the sorbent layers 100 to the support 101.

Support 101 may be a connecting element, allowing an electrical current to be transmitted through the volume of solder 102 onto the sorbent 100.

In Figure 11A and 11B, several layers of sorbent 110 are arranged between the free ends of two arms 112, 113 of a support 111 (such as first support 2 and/or second support 3). By deformation of the arms 112, 113, as shown in Figure 11B, the layers 110 are fixed. The sorbent layers 110 are also provided with a metal tape 114 for allowing an electrical current to be transmitted to the substrate.

Claims

Conclusions

1. A CO2 sorption sorption module comprising: - a porous tubular sorbent for sorbing CO2 in a first state and for desorbing sorbed CO2 from the sorbent in a second state; - first and second supports connected to the sorbent and supporting the sorbent at spaced-apart opposite ends of the sorbent, supporting a central portion of the sorbent extending between the first and second supports by means of respective end portions of the sorbent abutting the first and second supports, the sorption module being adapted to flow a gaseous composition comprising CO2, such as ambient air, through the tubular sorbent between an interior and an exterior.

2. The sorption module of claim 1, wherein the first support provides an entrance to the sorption module and the sorbent is gas-permeable, thereby forming an exit from the sorption module.

Sorption module according to claim 1 or 2, wherein the sorbent comprises a plurality of superimposed layers and wherein the sorbent is preferably constructed from a single web, which web is at least wound around itself.

The sorbent module of claim 1, 2 or 3, wherein the sorbent is thermoresponsive.

5. Sorption module according to any of the preceding claims, further comprising connecting means for electrically and/or thermally connecting the sorbent to an energy source for providing energy to the sorbent, which are preferably provided at least on or near the end parts of the sorbent.

6. A sorption module according to claim 5, wherein the connecting means comprise at least one of: - a conductive layer, preferably a metal layer, the conductive layer preferably comprising one and more preferably two contiguous strips of material disposed between at least some, preferably a majority, and preferably all of the sorbent layers and/or on top of the outermost sorbent layer; and - an amount of thermally and/or electrically conductive solder or paste.

A sorbent module according to any preceding claim, further comprising at least one attachment means for securing the sorbent to the first and second supports and/or the plurality of layers of sorbent to each other, preferably comprising at least one of: - a wire and/or a coil wound around the sorbent in a path between the first and second supports; and - clamping means, such as at least one of a plastically deformable and/or resilient arm having a first end secured to at least one of the first and second supports and an opposite free end abutting an exterior of the sorbent, thereby urging one of the end portions of the sorbent toward said support.

8. A sorption module according to any preceding claim, wherein the sorbent comprises a plurality of fibers joined together to form a fabric, such as felt or a woven textile material.

9. A sorption module according to any preceding claim, wherein the sorbent comprises a) a carrier having an internal pore structure and b) an active ingredient provided within the internal pore structure which is capable of sorbing CO2.

10. A sorption module according to any preceding claim, wherein at least one of an inner diameter and an outer diameter of one of the end parts is equal to the same inner diameter and outer diameter of the other of the end parts, and wherein preferably the respective inner or outer diameter is constant between the end parts.

11. Sorption module according to any of the preceding claims, wherein a thickness of the sorbent between the first and the second support is constant.

The sorption module of any one of claims 1 to 10, wherein a thickness of the sorbent gradually increases from the first support towards the second support.

Sorption module according to any one of the preceding claims, wherein the thermal mass ratio between a) the first and the second support together with the end parts of the sorbent lying against them and b) the central part of the sorbent is in the range of from 0.001 to 0.50, preferably from 0.005 to 0.30, more preferably from 0.01 to 0.15, most preferably from 0.01 to 0.05.

14. A sorption module according to any preceding claim, wherein at least one of the first and second supports comprises a sealing member for sealing the sorption module in a gas-tight manner with respect to an opening in a wall.

15. Sorption module according to claim 14, wherein the sealing member comprises a, preferably resilient, connector which is connected to an end of at least one of the first and second supports that lies opposite the sorbent and which is preferably arranged around the circumference of this first or second support and is adapted to be inserted into the opening in the wall.

Sorption module according to claim 14 or 15, wherein the sealing part is suitable for thermally and/or electrically decoupling the wall of the sorbent, the sealing member preferably having a thermal conductivity of at most 3 W/K, more preferably at most 0.3 WIK, most preferably at most 0.03 W/K, and/or is electrically non-conductive.

17. Sorption module according to any one of the preceding claims, wherein the ratio between a) the length of the end parts of the sorbent and b) the length of the central part of the sorbent is at most 0.20, more preferably at most 0.10, most preferably 0.05.

18. A sorbent cartridge comprising: - a housing comprising a sorbent module receiving portion, and - at least one sorbent module according to any one of the preceding claims, received in the sorbent module receiving portion.

19. A sorbent cartridge according to claim 18, wherein the housing comprises at least one wall, preferably two spaced-apart walls, and wherein the sorbent module receiving portion comprises at least one and preferably more than one opening in at least one of the at least one wall, and preferably more than one opening in each of the respective walls, and wherein the at least one sorbent module is received in at least one of the at least one opening in the wall or walls.

The sorbent cartridge of claim 19, wherein the sorbent cartridge further comprises a peripheral wall extending between the two spaced-apart walls.

21. The sorbent cartridge of claim 18, 19 or 20, wherein at least a portion of the interior of the housing is reflective.

A sorbent cartridge according to any one of claims 18 to 21, wherein the sorbent module receiving portion, preferably the at least one opening in the at least one wall, is configured to axially and radially lock the sorbent module at one end thereof and wherein the sorbent module receiving portion, preferably the at least one opening in the other wall, is arranged to radially lock the sorbent module while allowing axial displacement over a length less than the length of a sealing member.

A method of manufacturing a sorption module according to any preceding claim, comprising the steps of: a) providing first and second supports at spaced-apart holding positions; b) applying to the first and second supports a porous sorbent for sorbing CO₂ in a first state and for desorbing sorbed CO₂ from the sorbent in a second state; and i) causing relative movement of the first and second supports with respect to the sorbent such that the sorbent is wrapped around the first and second supports such that at least a portion of the first support and a portion of the second support are covered by the sorbent.

24. A method according to claim 23, wherein in step a) the first and second supports are provided on a spindle.

25. A method according to claim 23 or 24, wherein the relative movement causes at least a portion of the sorbent to wind around itself one or more times.

26. The method of claim 23, 24 or 25 further comprising the step of: d) with the first and second supports disposed in the holding positions, applying connecting means to the porous sorbent for electrically and/or thermally connecting the sorbent to an energy source for providing energy to the sorbent on or near the first and second supports.

27. The method of claim 26, wherein the sorbent is a felt and the connecting means is a conductive layer such as a metal layer, wherein the relative movement in step ¢) causes the conductive layer to be wound between the respective layers of felt.

28. A method for collecting CO from air, comprising the steps of: a) providing a sorption module according to any one of claims 1 to 17, or a sorption cartridge according to any one of claims 18 to 22, or a sorption module obtainable by a method according to any one of claims 23 to 27; b) arranging the first support of the sorption module downstream of a gas inlet and arranging the sorbent exterior of the sorption module upstream of a gas outlet; c) performing at least one sorption and desorption cycle, wherein one sorption and desorption cycle comprises the steps of:

c1) flowing air from the gas inlet through the sorption module to the gas outlet, thereby sorbing CO from the air onto the sorbent of the sorption module;

c2}) passing an electric current through the sorbent to desorb sorbed

CO: from the sorbent;

c3) collecting the CO2 desorbed from the sorbent.