Device and method for separating a gas and / or air moisture from the ambient air

Abstract

The invention relates to an installation (10) for separating a gas and / or air moisture from the ambient air (11). The installation comprises a flow generator (24) for conveying the ambient air (11) through the installation (10), a process chamber (12) for drying the ambient air (11) and / or a process chamber (30) for separating a gas, in particular carbon dioxide (70), from the ambient air (11). In the process chamber (12, 30) there is arranged a sorption element (16, 36) with a sorbent material (18, 38) for binding air moisture from the ambient air (11) and / or for separating a gas, in particular carbon dioxide (70), from the ambient air (11). According to the invention, the second sorption element (34) has a plurality of heatable sorption cells (60-68) which are arranged in at least two different cascades (50-58) in the flow direction of a gas stream (72) through the second process chamber (30), and at least two heating elements (40, 41), wherein at least one heating element (40, 41) is allocated to each cascade (50-58), and wherein the ambient air (11) flows through the cascades (50-58) in series such that the waste heat of the sorption cells (60) of the first cascade (50) is transferred to the sorption cells (62) of the second cascade (52).

Description

[0001] Description

[0002] Device and method for separating a gas and / or humidity from the ambient air

[0003] The invention relates to a device for separating a gas or humidity from the ambient air and to a method for separating a gas or humidity from the ambient air according to the preamble of the independent patent claims.

[0004] To reduce carbon dioxide emissions in the ambient air and achieve climate neutrality, not only must carbon dioxide emissions be reduced, but unavoidable carbon dioxide emissions must also be compensated accordingly. One option for compensating these carbon dioxide emissions is to capture carbon dioxide from the ambient air. This process is also known as a direct air capture process and is suitable for reducing the proportion of carbon dioxide in the atmosphere. Alternatively or additionally, carbon dioxide emissions can be compensated by permanently storing carbon dioxide in a reservoir, particularly in a rock layer, thus preventing it from entering the atmosphere.

[0005] Systems and methods for capturing carbon dioxide from ambient air are known from the prior art. Such capture can be carried out using the so-called "direct air capture" process, whereby the carbon dioxide can be captured directly from the ambient air, stored, or fed into a further process. Most known methods for capturing carbon dioxide from ambient air employ a cyclic process using a combination of pressure and / or temperature changes. In a first process step, the carbon dioxide present in the atmospheric air is bound in a sorption element. The carbon dioxide bound in the sorption element can be released again in a second process step.The development of suitable adsorption materials and their technical implementation in appropriate adsorption systems aims to enable efficient and energetically effective carbon dioxide capture. One challenge is the development of efficient adsorption systems in which the sorption elements are technically arranged and / or designed in such a way that, on the one hand, the adsorption and desorption of carbon dioxide proceeds optimally and, on the other hand, a comparatively cost-effective system concept can be implemented. In particular, the heating and cooling phases influence the process costs, while the design of the sorption element and the process chamber influence the system costs. A further disadvantage of the known solutions is that the sorbent materials used, especially physisorbents, are sensitive to moisture.This means that the sorbent is capable of absorbing even the residual moisture from the dried air into the porous microstructure, which directly reduces the absorption capacity for carbon dioxide from the ambient air. In practical terms, this would mean that the process becomes less efficient, resulting in a much lower carbon dioxide yield for the same energy consumption in the capture process. This fact means that sorbent regeneration would have to be introduced into the process to remove the moisture from the sorbent. This would further worsen the energy balance of the process. According to the current state of the art, the sorbent material is primarily heated to the desired temperature using heat exchangers.The conventionally known sorbent materials have very poor thermal conductivity, which has a negative impact on the overall energy costs, especially during desorption.

[0006] EP 3 151 947 B1 discloses a vacuum chamber for a direct air capture process, which encloses an interior space for accommodating an adsorber structure. The interior space is defined by a wall in which at least one inlet cover and one outlet cover are arranged. In an open position, the covers allow gas to circulate through the vacuum chamber to contact the adsorber structure. In a closed position, the covers seal the vacuum chamber, allowing the interior of the vacuum chamber to be evacuated.

[0007] EP 3 166 708 B1 discloses a method and device for the regeneration of materials that can achieve both a high cyclic yield in cyclic adsorption and desorption processes and a high purity of the desorbed gas during gas separation. The underlying principle is the combination of temperature-vacuum swing adsorption-desorption cycles, which are known to produce a desorption gas of high purity, with the addition of steam as a purge gas, which is known to support desorption processes and enable a high cyclic yield with short process times. A process chamber is evacuated to a pressure of 20–400 mbar, and the sorption material is preheated to a temperature of 35–80°C.To support the desorption of carbon dioxide, water vapor is introduced into the process chamber, which expels the carbon dioxide from the sorption material and thus supports the yield of carbon dioxide at comparatively low process temperatures in a comparatively energy-efficient process.

[0008] Furthermore, WO 2007 / 054255 A1 discloses a process for producing a sorbent-containing coating on a substrate, using an adhesion-promoting component in liquid or dissolved form. The coating is applied to the substrate at a temperature between 100°C and 500°C and at a pressure lower than ambient pressure.

[0009] The invention is based on the object of improving the energy efficiency of a plant for separating a gas, in particular carbon dioxide, from the ambient air and at least partially overcoming the disadvantages known from the prior art.

[0010] The object is achieved by a system for separating a gas, in particular carbon dioxide, and / or humidity from the ambient air. The system comprises a flow generator, in particular a blower, for conveying the ambient air through the system, a process chamber for drying the ambient air and / or a process chamber for separating a gas, in particular carbon dioxide, from the ambient air. A sorption element with a sorbent material for binding humidity from the ambient air is arranged in the process chamber and / or a sorption element with a sorbent material for separating a gas, in particular carbon dioxide, from the ambient air is arranged in the process chamber. According to the invention, the sorption element has a plurality of heatable sorption cells, which are arranged in at least two different cascades in the flow direction of a gas stream through the process chamber.Furthermore, at least two heating elements are provided, with at least one heating element assigned to each cascade. Ambient air flows through the cascades in series such that the waste heat from the sorption cells of the first cascade is transferred to the sorption cells of the second cascade.

[0011] The system according to the invention enables particularly efficient separation of a gas, in particular carbon dioxide and / or humidity, from the ambient air. The cascaded design of the sorption element in the process chamber enables energy-efficient desorption of the gas, in particular carbon dioxide, from the sorbent material, thereby achieving a high yield of the gas, in particular carbon dioxide, with relatively low energy consumption and minimizing waste heat losses.

[0012] The features listed in the dependent claims enable advantageous improvements and further developments of the system listed in the independent claim for separating a gas, in particular carbon dioxide and / or humidity from the ambient air.

[0013] In a preferred embodiment of the system, the system has a first process chamber for drying the ambient air, wherein a first sorption element with a first sorbent material for binding humidity from the ambient air is arranged in the first process chamber. The system further comprises a second process chamber downstream of the first process chamber in the flow direction of the ambient air through the system for separating a gas, in particular carbon dioxide, from the ambient air dried in the first process chamber. A second sorption element with a second sorbent material for separating the gas, in particular carbon dioxide, from the ambient air is arranged in the second process chamber. The second sorption element comprises a plurality of heatable sorption cells, which are arranged in at least two different cascades in the flow direction of a gas flow through the second process chamber.Furthermore, the second sorption element comprises at least two heating elements, with at least one heating element assigned to each cascade. Ambient air flows through the cascades serially, so that the waste heat from the first cascade is transferred to the sorption cells of the second cascade.

[0014] In a preferred embodiment of the system, each cascade comprises several sorption cells, with the dried ambient air flowing through the sorption cells of one cascade in parallel and the sorption cells of different cascades flowing through them in series. This enables efficient flow through the sorption material in the second process chamber and separation of the gas, in particular carbon dioxide, from the ambient air. Furthermore, efficient transfer of heat from the sorption cells of a first cascade in the flow direction through the process chamber to the sorption cells of a subsequent cascade in the flow direction can be achieved. This heats up the subsequent cascade and minimizes the heating times and energy requirements for heating the sorption cells of the subsequent cascade.

[0015] In a further preferred embodiment of the invention, the system comprises two or more first process chambers, wherein flow can pass through the two or more first process chambers in parallel, and the second process chamber is arranged downstream of the first process chambers. A plurality of first process chambers arranged in parallel enables particularly efficient drying of the ambient air before it is fed to the second process chamber. Furthermore, the first process chambers can be made smaller when divided into two or more first process chambers, thereby allowing for greater freedom in the design of the system for separating atmospheric humidity and / or a gas, in particular carbon dioxide, from the ambient air.

[0016] According to a preferred embodiment of the system, a control element, in particular a control valve or a control flap, is arranged between the first process chamber and the second process chamber, with which the gas supply to the second process chamber can be controlled. This allows the drying process and the adsorption process to be coordinated accordingly, so that a corresponding amount of dried ambient air can be supplied to the second process chamber at a corresponding flow rate, which is particularly favorable for the adsorption of the carbon dioxide present in the dried air.Furthermore, the control element can prevent the air supply to the second process chamber in a desorption phase of the process for separating the gas, in particular carbon dioxide, in order to release the gas, in particular carbon dioxide, bound in the sorbent material of the second process chamber and to supply it in a correspondingly concentrated manner to a gas storage device, in particular a carbon dioxide storage device.

[0017] In an advantageous embodiment of the system, a first flow generator, in particular a first blower, is assigned to the first process chamber, and a second flow generator, in particular a second blower, is assigned to the second process chamber in order to convey a gas flow through the respective process chamber. This allows the flow velocity of the gas flow in the two process chambers to be controlled independently of one another, so that the flow velocity can be optimally adapted to the process taking place in the process chambers. In an advantageous embodiment of the system, each sorption cell of the sorption element has a heating element. This enables particularly efficient heating of the sorption cells and thus particularly energy-efficient desorption of the gas bound in the sorbent material of the sorption cells, in particular carbon dioxide and / or the atmospheric humidity bound in the sorption cell.Furthermore, by integrating a heating element into the sorption cells, a particularly favorable filling of the sorption material can be achieved, whereby the adsorption and subsequent desorption of the gas, in particular carbon dioxide, can be carried out in a particularly energy-efficient manner.

[0018] In a preferred embodiment of the invention, a pressure reduction unit for generating a negative pressure in the process chamber is arranged at least in one of the process chambers. Reducing the pressure in the first process chamber can improve the regeneration of the sorbent material for drying the ambient air. A corresponding pressure reduction in the second process chamber can facilitate the release of the gas, in particular carbon dioxide, from the sorbent material during the desorption phase, thereby increasing the yield of gas, in particular carbon dioxide, and improving energy efficiency.

[0019] In an advantageous embodiment of the system, the second sorbent material is a physical sorbent material, in particular a zeolite. Physisorbents are particularly suitable for binding carbon dioxide from dry air and later releasing it again. However, since physisorbents have a correspondingly high affinity for atmospheric humidity, it is necessary to sufficiently dry the ambient air gas stream beforehand in order to increase the yield of adsorbed gas, in particular carbon dioxide, and thus improve the efficiency of the process. Since such sufficient drying is provided by the upstream first process chamber, a physical sorbent material, in particular a zeolite, is particularly suitable for a system according to the invention for separating the gas, in particular carbon dioxide, from the ambient air.

[0020] According to a preferred embodiment of the system, the second process chamber is connected to a gas storage device, in particular a carbon dioxide storage device. Such a connection to a gas storage device, in particular a carbon dioxide storage device, enables particularly simple removal of the desorbed gas, in particular the desorbed carbon dioxide, from the second process chamber for further use in a subsequent process or for permanent storage. In an advantageous embodiment of the invention, a temperature sensor, a pressure sensor, and / or a sensor for detecting a gas concentration, in particular the carbon dioxide concentration, in the process chamber is arranged in one of the process chambers.Since the adsorption and desorption of carbon dioxide takes place in a temperature-pressure swing process, it is advantageous to monitor the temperature in the second process chamber, the absolute pressure, and the gas concentration, especially the carbon dioxide concentration, in order to be able to control the process accordingly and efficiently. The proposed sensors therefore enable particularly favorable control or regulation of the process for separating the gas, especially carbon dioxide, in the second process chamber.

[0021] According to an advantageous embodiment of the system, the system is provided with a control device for controlling the flow generator and the at least two heating elements. This enables central control of the system, so that the individual process steps of a method for separating the gas, in particular carbon dioxide, from the ambient air, in particular the drying of the ambient air and the subsequent adsorption and desorption of the carbon dioxide, can be carried out as energy-efficiently as possible.

[0022] In an advantageous embodiment of the system, the heating elements are designed as heating coils or heating mats. A heating coil or heating mat is particularly suitable for heating the sorption cells of a cascade, as it can be integrated into the sorption element in the second process chamber particularly easily and in a space-saving manner.

[0023] A further aspect of the invention relates to a method for separating a gas, in particular carbon dioxide and humidity from the ambient air using such a system, the method comprising the following process steps:

[0024] Conveying the ambient air into a first process chamber, drying the ambient air in the first process chamber, passing the dried ambient air into a second process chamber,

[0025] - Adsorbing the gas contained in the dried ambient air, in particular carbon dioxide, in the sorbent material of the sorption cells of the second process chamber, evacuating the second process chamber, desorbing the gas, in particular carbon dioxide, wherein firstly the heating element of the first cascade is activated in order to release the gas, in particular carbon dioxide, from the sorption cells of the first cascade and then the heating element of the second cascade is activated in order to release the gas, in particular carbon dioxide, from the sorption cells of the second cascade.

[0026] The process according to the invention enables a particularly energy-efficient separation of a gas, in particular carbon dioxide, from the ambient air, since the waste heat from the heated sorption cell in the first cascade is transferred to the subsequent cascades, thus facilitating heating. Furthermore, the cascaded design of the sorption element in the second process chamber allows for a particularly favorable arrangement of the sorbent material, thereby increasing the yield of gas, in particular carbon dioxide, separated from the ambient air.

[0027] In an advantageous embodiment of the method, the sorption cells are heated to a target temperature of 140°C to 220°C. Within this range, it can be ensured that the gas bound in the sorbent material, in particular carbon dioxide, is essentially completely desorbed from the sorbent material and can be used for further processing or permanent storage. The sorbent material is preferably a physisorbent, in particular a zeolite.

[0028] According to an advantageous embodiment of the process, the sorption cells are heated at a heating rate of 20°C per minute to 40°C per minute. Such a heating rate has proven to be a favorable compromise with regard to the required heating time and the required maximum heating power, thus keeping the system's cycle times reasonably short and achieving a correspondingly high yield of gas, especially carbon dioxide.

[0029] The various embodiments of the invention mentioned in this application can be advantageously combined with one another, unless otherwise stated in the individual case.

[0030] The invention is explained below in exemplary embodiments with reference to the accompanying drawings. They show:

[0031] Figure 1 shows a state-of-the-art system for separating

[0032] Carbon dioxide from the ambient air, Figure 2 shows a prior art adsorption chamber for such

[0033] Attachment,

[0034] Figure 3 shows a system according to the invention for separating a gas, in particular carbon dioxide, from the ambient air and / or for drying the ambient air in a schematic representation,

[0035] Figure 4 shows a preferred embodiment of a sorption cell of a plant according to the invention for separating a gas, in particular carbon dioxide, from the ambient air and / or for drying the ambient air,

[0036] Figure 5 shows a further preferred embodiment of a sorption cell for a

[0037] Plant for separating a gas, in particular carbon dioxide, from the ambient air and / or for drying the ambient air,

[0038] Figure 6 shows a further preferred embodiment of a sorption cell for a

[0039] Plant for separating a gas, in particular carbon dioxide, from the ambient air and / or for drying the ambient air,

[0040] Figure 7 shows a preferred embodiment of a system according to the invention for

[0041] Separation of a gas, in particular carbon dioxide from the ambient air and / or for drying ambient air in a schematic representation,

[0042] Figure 8 shows a further preferred embodiment of an inventive

[0043] Plant for the separation of a gas and / or humidity, in particular for the separation of carbon dioxide from the ambient air,

[0044] Figure 9 is a schematic representation of a process room with several

[0045] Cascades of sorption cells for a system according to the invention for separating a gas and / or humidity from the ambient air, Figure 10 shows a heating element in the form of a heating coil for a system according to the invention for separating a gas and / or humidity from the ambient air,

[0046] Figure 11 shows a collection of possible heating elements in the form of heating mats, which can be used to construct a sorption cell for a process room,

[0047] Figure 12 shows a preferred variant of a heatable carrier with a carrier material with a coating of a sorbent material,

[0048] Figure 13 shows a further preferred variant of a heatable carrier with a carrier material with a coating of a sorbent material, and

[0049] Figure 14 is a flow chart for carrying out a method according to the invention for separating a gas and / or air humidity, in particular for drying the ambient air and subsequently separating carbon dioxide from the dried ambient air.

[0050] Figure 1 shows a simplified schematic representation of a system 10 known from the prior art for separating carbon dioxide 70 from the ambient air 11. The system 10 comprises a process chamber 12 in which an adsorption chamber 14 for adsorbing carbon dioxide 70 is arranged. The adsorption chamber 14 comprises at least one sorption element 16 with a spherical sorbent material 18, which is preferably designed as a chemisorbent. The sorbent material 18 chemically binds carbon dioxide 70 from the ambient air 11 and thus removes the carbon dioxide 70 from the ambient air 11. Amine-functionalized, porous materials are particularly suitable as the sorbent material 18. The sorbent material 18 is stored in the adsorption chamber 14 as a fixed bed. For this purpose, a support frame 20 is provided for receiving the sorbent material 18, into which the sorbent material 18 is filled.The adsorption chamber 14 arranged in the process chamber 12 can be heated and cooled by a temperature control unit, in particular by a heat exchanger 22. The process chamber 12 has an inlet through which the ambient air 11 can flow into the process chamber 12 and which can be closed by a corresponding flap, hatch, or door. The system 10 further comprises a flow generator 24, in particular a fan 26, for conveying an air flow of the ambient air 11 through the process chamber 12. A pressure reduction unit 28, in particular a vacuum pump, is also provided on the process chamber 12 to at least partially evacuate the process chamber 12 and reduce the pressure in the process chamber 12 compared to the ambient pressure. A first outlet is also provided on the process chamber 12, which is preferably connected to the environment and enables the ambient air 11 to be discharged from the process chamber 12 into the environment.Furthermore, a second outlet is provided on the process chamber 12, through which a gas stream containing the separated carbon dioxide 70 can be discharged from the process chamber 12. The inlet and the outlets can be closed by appropriate control elements, in particular by valves, in order to seal the process chamber 12 gas-tight from the environment. The carbon dioxide 70 from the ambient air 11 is first absorbed in the sorbent material 18 in the adsorption chamber 14 in a known manner and, in a subsequent process step, is released again from the sorbent material 18 by temperature and pressure changes, optionally supported by the additional introduction of water vapor into the process chamber 12.

[0051] Figure 2 shows a schematic and simplified representation of an arrangement of adsorption chambers 14 in a process chamber 12 known from the prior art. Figure 2 shows a zigzag arrangement of several fixed beds, which accordingly support the sorbent material 18. Heat exchangers 22 are installed within the individual adsorption chambers 14 in order to heat the sorbent material 18 accordingly in the desorption process or to cool it again in a process step following the desorption process in order to precondition the sorbent material 18 for a renewed absorption of carbon dioxide 70.

[0052] The disadvantages resulting from the prior art can be seen in the system 10 shown in Figures 1 and 2. Depending on the process, the temperature control of the sorbent material 18 is energy-intensive and inefficient. The sorbent material 18 itself has low thermal conductivity and is formed from a bed of sorbent spheres. Due to the numerous heat transfers from sorbent sphere to sorbent sphere, the temperature control time is significantly extended, requiring high energy consumption and resulting in correspondingly high heat losses.

[0053] Figure 3 shows a schematic representation of a system 10 according to the invention for separating a gas to be adsorbed and / or air humidity from the ambient air 11. The system 10 is designed in particular as a system for drying an air stream of the ambient air 11 and for the subsequent separation of carbon dioxide 70 from the ambient air 11. The system 10 comprises a first process chamber 12 for dehumidifying the ambient air 11 and a second process chamber 30 for separating carbon dioxide 70 from the dried ambient air 11. The first process chamber 12 and the second process chamber 30 are fluidly connected to one another via an intermediate element 32. In the first process chamber 12, a plurality of sorption cells 100, 102, 104, 106, 108 are arranged, wherein each sorption cell 100, 102, 104, 106, 108 has a heatable carrier 36 which is encased and / or coated with a first sorbent material 18.The electrically heatable support makes it possible to introduce a defined amount of heat into the sorption cells 100, 102, 104, 106, 108 at a desired position in order to simplify the process control, in particular the drying of the ambient air. Silica gels and zeolites are particularly intended as the first sorbent material 18 for the first process chamber 12. In principle, however, any material is suitable that absorbs the moisture from the ambient air 11 and thus dries the gas stream 72 and makes it cyclically regenerable. The dried ambient air 11 is introduced into the second process chamber 30 via the intermediate element 32. A plurality of sorption cells 60, 62, 64, 66, 68 are arranged in the second process chamber 30, each having a support 36, a heating element 40, and a second sorbent material 38. Preferably, the carrier 36 is coated and / or encased with the second sorbent material 38.The second sorbent material 38 can differ from the first sorbent material 18 with regard to its chemical composition and structural design. Preferably, the second sorbent material 38 is a physisorbent, in particular a zeolite. The primary function of the second sorbent material 38 is to adsorb carbon dioxide 70 from the gas stream 72 of the dried ambient air 11. Accordingly, any material suitable for physically and / or chemically binding carbon dioxide and subsequently releasing it again in a desorption process is suitable as the second sorbent material 38. The system 10 further comprises a flow generator 24, in particular a blower 26, for conveying a gas stream 72 of the ambient air 11 through the two process chambers 12, 30.At least in the second process chamber 30, a pressure reduction unit 28, a pressure sensor 42, a temperature sensor 44, and a gas sensor 46 for detecting the carbon dioxide concentration are also arranged. Preferably, at least one pressure reduction unit 28, a pressure sensor 42, and a temperature sensor 44 are also arranged in the first process chamber 12. The system 10 further comprises a central control device 114, via which different profiles can be mapped during the drying of the ambient air 11, during the adsorption of the carbon dioxide 70, and during the desorption of the carbon dioxide 70. Compared to systems 10 known from the prior art, the system 10 according to the invention eliminates the need for complex and energy-intensive temperature control devices such as heat exchangers, allowing the system 10 to be designed in a simpler, more cost-effective, and more compact manner. The temperature of the sorbent materials 18, 38 is controlled directly by heating the supports 36.

[0054] Figure 4 shows a preferred embodiment of a sorption cell 60, 62, 64, 66, 68 according to the invention for a process chamber 12, 30 of a system 10 according to the invention for drying ambient air 11 and subsequently separating a gas, in particular carbon dioxide 70, from the dried ambient air 11. Preferably, the sorption cells 100, 102, 104, 106, 108 of the first process chamber 12 are constructed similarly or identically to the sorption cells 60, 62, 63, 66, 68 for separating the gas. The description of the embodiment is a general explanation of design and function. It is assumed that any sorbent materials 18, 38 can be used for adsorption and desorption cells 60, 62, 64, 66, 68. The sorbent material 18, 38 can be a sorbent material 18 for drying the ambient air 11 or a sorbent material 38 for adsorbing carbon dioxide 70.In principle, however, the sorption cell according to the invention is also suitable for adsorbing other gases. The sorption cell 60 comprises a metallic support 36, which is designed as an electrical heating element 40. Due to the process, the heating element 40 has the function of heating sorbent material 18, 38 in the sorption cell 60 and thus drying the ambient air 11, assisting the desorption of carbon dioxide, and / or regenerating the sorbent material 18, 32 of the sorption cell 60.

[0055] In addition to its heating function, the metallic support 36 serves as a structural support, to which sorbent materials 18, 38 are attached on both sides. This can be achieved, in particular, by coating or encasing the support 36 with the sorbent material 18, 38. One or more supports 36 form a sorption cell 60, which is manufactured to be compact and robust in order to demonstrate full functionality in industrial use over a planned service life of at least 10 years. The sorbent material 18, 38 is a purely porous material coating on the support 36. In this exemplary embodiment, the support 36 of the sorption cell 60 is made of a metallic fine wire mesh. The finished woven and / or welded heating element 40 has corresponding connections to the power supply 122. The design of the heating element 40 depends on many factors.It is assumed that different combinations are possible with regard to the selection of wire diameter, surface quality, mesh size, material selection, and manufacturing processes. The invention is not limited to the exemplary embodiment shown in Figure 4; during the manufacture of the sorption cell 60, care must be taken to ensure that the peripheral surfaces 126 are reproduced uniformly and without defects. This involves, on the one hand, covering the heating element 40 with sorbent material 18, 38 and, on the other hand, ensuring that these peripheral surfaces 126 provide a corresponding seal with a system wall when the sorption cell 60 is installed in a process chamber 12, 30 of the system 10.

[0056] After production, the finished sorption cell 60 has a plurality of openings 124 distributed in a grid. The size of the openings 124 is determined in particular by the mesh size of the electric heating element 40. The webs of the support 36, which can also have different dimensions, are located between the openings 124. The sorbent materials 18, 38 are designed such that the entire surface of the sorption cell 60 ensures full activity during adsorption, desorption, drying, and regeneration. The distribution and shape of the openings 124 of the sorption cell 60 can be designed differently. One embodiment is shown in section AA, in which the openings 35 are distributed symmetrically. In another possible embodiment, shown in section A'-A', the supports 36 of the sorption cell 60 are arranged slightly offset.The displacement of the openings 124 can enable better wetting of the surface of the sorbent material 18, 38 with the ambient air 11, which can lead to improved adsorption and desorption of carbon dioxide 70.

[0057] In addition to the sorption cell designs shown in Figure 4, further embodiments are possible, so that the invention is not limited to the embodiments shown in Figure 4. For this purpose, Figure 4 shows further possible final design shapes of sorption cells 60, such as a rectangular shape, a triangle or square design, or a plurality of adjacent squares.

[0058] Figure 5 shows a further preferred embodiment of a sorption cell 60 for a system 10 for separating carbon dioxide 70 from the ambient air 11. The basic structure corresponds to the structure described in Figure 4. In contrast to the embodiment in Figure 4, in this embodiment, the openings 124 are circular. The openings 124 can be designed symmetrically or asymmetrically along the entire surface of the sorption cell 60. The diameter of the openings 124 can vary in the range from 0.1 mm to 5 mm. The metallic carrier 36 can be designed as a mesh or as a specific contour, whereby a controlled current flow is provided by a power supply 122. The carrier 36 has corresponding connections for the power supply 122.As in the embodiment in Figure 4, in this embodiment, other design shapes of sorption cells 60 are also possible, such as rectangle, triangle, square, multiple squares.

[0059] Figure 6 shows a further preferred embodiment of a sorption cell 60. The structure essentially corresponds to the structure described in Figure 4. However, in the embodiment shown in Figure 6, the sorption cell 60 has no visible openings 124. Instead of visible openings 124, a sorbent material 18, 38 with a high degree of surface roughness is used here, wherein the surface is designed similarly to the surface of a rice cake. The structure of the sorbent material 18, 38 is manufactured such that a gas stream 72 of the ambient air 11 flows not only partially perpendicular to the sorption cell 60 through the process chamber 12, 30, but at least partially along the rough surface of the sorption cell 60. The flow path of the ambient air is shown in section AA in Figure 6. The flow paths through the sorption cell 60 can be designed symmetrically or asymmetrically along the entire surface.

[0060] As with other embodiments, the design of the electrically heatable support 36 can be varied. Figure 6 shows four different configurations in the form of a mesh, a meander, a meander with a return line, and a heating coil. The electrically heatable support 36 has a power connection 122 in each case.

[0061] Figure 7 shows a schematic representation of a preferred embodiment of a system 10 according to the invention for separating carbon dioxide 70 from the ambient air 11. The system 10 comprises a first process chamber 12 for separating atmospheric humidity from the ambient air 11 and a second process chamber 30, connected to the first process chamber 12 via an intermediate element 32, in particular via a connecting line, for adsorbing and subsequently desorbing carbon dioxide 70 from the gas stream 72 of the ambient air 11 dried in the first process chamber.

[0062] The first process chamber 12 has a plurality of sorption cells 100, 102, 104, 106, 108, through which air flows one after the other. Any material that extracts moisture from the ambient air 11 and can be periodically regenerated is suitable as the sorbent material 18 for the sorption cells 100, 102, 104, 106, 108. Preferably, the sorbent material 18 is a material known for drying, such as silica gel, zeolite A3, or the like. The first process chamber 12 is connected to the second process chamber 30 via the connecting line in such a way that semi- and fully automatic control is possible. The sorption cells 60, 62, 64, 66, 68 according to the invention described in the previous sections are installed in the second process chamber 30. The sorbent material 38 used for the second process chamber 30 is suitable for the adsorption and desorption of carbon dioxide 70.The second sorbent material 38 is preferably a physical sorbent material, in particular a zeolite. Due to their robustness, zeolites are particularly well suited as adsorbers for the capture of carbon dioxide. Alternatively or additionally, the sorption cells 100, 102, 104, 106, 108 of the first process chamber 12 can also be designed like the sorption cells according to the invention described in the previous sections. The sorption cells 100, 102, 104, 106, 108 of the first process chamber 12 and the sorption cells 60, 62, 64, 66, 68 of the second process chamber 30 each have an electrical connection 122, which are correspondingly connected to the control device 114 for the overall system control. The energy for heating is provided at the desired current and voltage level, either constantly or pulsed (AC / DC), via a fully regulated power unit 120.Preferably, a corresponding adjustment of voltage profiles (e.g., pulsating direct voltage, sinusoidal alternating voltage, etc.) is possible in the case of pulsed control. Furthermore, the system 10 comprises a pressure reduction unit 28, in particular a vacuum pump 112, which extracts the residual air from the second process chamber 30 before desorption takes place or supports the desorption itself in the second process chamber 30. In addition, the pressure reduction unit 28, in particular the vacuum pump 112, can support the drying of the air and / or the regeneration of the sorbent material 18 in the first process chamber 18. Furthermore, the system has a carbon dioxide storage unit 110 for absorbing the carbon dioxide desorbed from the second sorbent material 38 in the second process chamber 30.

[0063] The system 10 further comprises at least one flow generator 24, in particular a blower 26, for directing a gas stream 72 of the ambient air 11 through the process chambers 12, 30. The system 10 preferably has a first flow generator 24, in particular a first blower 26, which conveys the ambient air 11 into the first process chamber 12, and a second flow generator 48, in particular a second blower 26, which conveys the dried gas stream 72 of the ambient air 11 into the second process chamber 30. Furthermore, a pressure sensor 42, a temperature sensor 44, a gas sensor 46 for detecting the air humidity, or a gas sensor 46 for detecting the concentration of carbon dioxide 70 can be arranged at the process chambers 12, 30, via which the control device 114 receives corresponding information for the overall system control.The sorption cells 100, 102, 104, 106, 108 of the first process chamber or the sorption cells 60, 62, 64, 66, 68 of the second process chamber 30 are electrically connected to the control device 114. This makes it possible to control the sorption cells 60, 62, 64, 66, 68, 100, 102, 104, 106, 108 as desired or to heat the desired sorption cell 60, 62, 64, 66, 68, 100, 102, 104, 106, 108 to the desired temperature via temperature sensors integrated into the sorption cells, via temperature control or current regulation, thus enabling optimal process control.

[0064] Detail "A" shows the sorption element 34 of the second process chamber 30. The individual sorption cells 60, 62, 64, 66, 68 are designed as described for Figures 3 to 5. Preferably, each sorption cell 60, 62, 64, 66, 68 has its own power supply 122. When designing the system 10, all construction guidelines regarding issues such as expansion, sealing, insulation, etc. are taken into account.

[0065] Figure 8 shows a further preferred embodiment of a system 10 according to the invention for separating carbon dioxide 70 from the ambient air 11. With essentially the same functional structure as described for Figure 7, the system has a 2 + 1 configuration, i.e. two first process chambers 12, 13 connected in parallel for drying the ambient air 11 and a second process chamber 30 for separating carbon dioxide 70 from the ambient air 11.

[0066] After the first flow generator 24 is switched on, the ambient air 11 flows into the system 10, and the ambient air 11 is dried in the first process chambers 12, 13. The air humidity separates at the sorption cells 100, 102, 104, 106, 108. Parallel to or following this, a gas stream 72 of dried ambient air 11 flows into the second process chamber 30, where the air molecules come into contact with the sorption cells 60, 62, 64, 66, 68, and the carbon dioxide molecules are adsorbed onto the second sorbent material 38. When the sorption cells 100, 102, 104, 106, 108 of the first process chamber 12 are saturated with humidity, the flow generator 24 for the other first process chamber 13 switches on and takes over the air drying in the first process chamber 13. At the same time, the regeneration or activation of the sorption cells 100, 102, 104, 106, 108 begins in process chamber 12 according to the method according to the invention.Regeneration or activation in this context means that the first sorbent material 18 of individual sorption cells 60, 62, 64, 66, 68 is freed of water. The water must diffuse out of the sorbent structure so that renewed air drying can be carried out periodically in continuous operation with the sorption cells 100, 102, 104, 106, 108. During the regeneration of the sorption cells 100, 102, 104, 106, 108, the vacuum pump 112 can optionally be switched on for support. In the two process chambers 12, 13 for air drying, a known design solution is implemented to remove the condensate and / or the water collection from the first process chambers 12, 13 via channels, separators, filters, etc.

[0067] To separate carbon dioxide 70 in the second process chamber 30, corresponding sensors are provided, which signal to the control unit 114 that the sorption cells 60, 62, 64, 66, 68 are saturated with carbon dioxide. If this is the case, the second process chamber 30 is decoupled from the gas stream 72, which can be done in particular by suitable shut-off valves, and an evacuation of the second process chamber 30 is initiated by means of the vacuum pump 112 in order to pump out the residual air from the dead volume of the second process chamber 30 so that the adsorbed carbon dioxide 70 is not contaminated. In parallel or subsequently, the control device 114 initiates the desorption of the carbon dioxide 70 from the sorbent material 38 of the second process chamber 30, whereby the carbon dioxide storage 110 is filled with carbon dioxide 70. For this purpose, the sorption cells 60, 62, 64, 66, 68 are heated accordingly.The heating elements 40 integrated into the support elements 36 transfer heat more homogeneously and quickly, without heat transfer or other heat losses, directly from the heating element 40 to the sorbent material 38. The temperature increase to 150–220°C unstables the physical bond between the carbon dioxide molecules and the zeolite, allowing the desorption process to proceed optimally with the vacuum support. Once desorption is complete, an additional temperature increase can optionally be preprogrammed (e.g., to 250°C with a 15-minute ramp). This would result in a slight activation of the sorbent material 38 to remove any residual moisture from the sorbent material 38.

[0068] Figure 9 shows a preferred example for controlling a system 10 according to the invention for drying an air stream from ambient air 11 and for the subsequent separation of carbon dioxide 70 from the ambient air 11. Figure 9 represents a schematic representation of the activation plan of the sorption cells 60, 62, 64, 66, 68 in the second process chamber 30 during the desorption of the carbon dioxide 70. The control of the sorption cells 60, 62, 64, 66, 68 takes place in the form of cascades 50, 52, 54, 56, 58 of sorption cells 60, 62, 64, 66, 68. Each cascade 50, 52, 54, 56, 58 is assigned several sorption cells 60, 62, 64, 66, 68, wherein The sorption cells within a cascade are preferably flowed through in parallel, and the cascades are flowed through serially. At the beginning of the desorption process, the second process chamber 30 has a starting temperature of, for example, 35°C.After the air has been evacuated from the second process chamber 30, the heating elements 40 of the sorption cells 60 of the first cascade 50 are switched on and heat the sorption cells 60 at a heating rate of 30°C / min. After approximately 6 minutes, the sorption cells 60 of the first cascade 50 reach the target value of 200°C. The vacuum pump 112 assists the desorption and ensures that warm carbon dioxide molecules leave the sorption cells 60 and are passed on to the carbon dioxide storage 110. The gas stream transfers heat to the second cascade 62 following downstream in the flow direction. This results in the sorption cells 62 of the second cascade 52 having a higher initial temperature of, for example, 40°C before the heating elements 41 of the sorption cells 62 of the second cascade 52 are activated.This shortens the required heating time from cascade to cascade for the same heating output, with the last cascade 58 having the shortest heating time. Thus, the required activation time of the heating elements 41 is reduced from cascade to cascade, which also reduces energy consumption.

[0069] The cascaded design of the sorption element 34 in the second process chamber 30 allows for a further optimized energy balance during desorption, as the duty cycle (ED) becomes increasingly shorter from cascade to cascade. The power supply to the heating elements 40, 41 of the sorption cells 60, 62, 64, 66 is regulated accordingly, ensuring homogeneous heating within the cascade. The cascaded design and control strategy can also be used for the sorption cells 100, 102, 104, 106, 108 of the first process chamber 12. Such a system design enables numerous control strategies and can significantly reduce energy consumption.

[0070] Figure 10 shows another possible design for the electrically heatable support element 36, which serves as the heating element 40. It is a heating coil 99, which is connected to a power source 90 and can be controlled with various AC and / or DC pulse profiles. In practical terms, this would mean that a pulsating power supply can generate additional electromagnetic radiation in addition to the heating, which can also support the desorption of carbon dioxide 70 from the sorbent material 38.

[0071] Alternatively, the heating element 40 can also be integrated onto an additional support or a sieve to increase rigidity. Preferred sorbent materials 18, 38 for the sorption cells 60, 62, 64, 66, 68, 100, 102, 104, 106, 108 are physical sorbents such as zeolites, silica materials, MOFs (metal organic frameworks), activated carbon, COFs (covalent organic frameworks), carbon molecular sieves, materials based on alkali metals or metal oxides, ordered porous carbon, ACFs (activated carbon fibers), graphene, CMS (carbon molecular sieves), and composites thereof. Alternatively, chemical adsorbents such as potassium carbonate (K2CO3), sodium nitrate (NaNO3), aluminum oxide (AI2O3), zirconium dioxide (ZrCh), titanium dioxide (TiC>2), manganese dioxide (MnCh), zinc oxide (ZnO) and binary eutectic mixtures consisting of potassium nitrate (KNO3) and lithium nitrate (UNO3) can be used as sorbent materials 18, 38.Furthermore, a polymer with a nitrogen-containing functional group, for example, with an amino group or an imine group, can be used as the sorbent material 18, 38. Solid sorbents made of one of the following polymers: polyethyleneimine (PEI), polyallylamine (PAA), tetraethylenepentamine (TEPA), pentaethylenehexamine (PEHA), or polyethyleneimine-modified silica gel are also possible. A (macroporous) divinylbenzene-crosslinked polymer with primary amino groups is particularly preferred as a solid sorbent. An example of a (macroporous) divinylbenzene-crosslinked polymer with primary amino groups is Lewatit® VP OG 1065.

[0072] Depending on which sorbent material 18, 38 is used to produce a sorption cell 60, 62, 64, 66, 68, 100, 102, 104, 106, 108, other directly heatable methods or heating elements 40 could also be used as electrically heatable supports 36 of a sorption cell 60, 62, 64, 66, 68, 100, 102, 104, 106, 108.

[0073] Figure 11 shows a collection of possible heating elements 40 in the form of heating mats 92, which can be used to construct a sorption cell 60, 62, 64, 66, 68, 100, 102, 104, 106, 108 for a process chamber 12, 13, 30. In particular, a heating mat 92 with an integrated heating wire 98 or a heating fabric 96, in particular a carbon heating fabric, or a heating surface 94, in particular a carbon heating surface, can be used.

[0074] Figure 12 shows a preferred variant of a heatable carrier 36 with a carrier material 116 with a coating 118 with a sorbent material 38. The carrier material 116, in particular a wire mesh, is simultaneously the heating element 40. The wire mesh comprises warp threads and weft threads which form the wire mesh. In the embodiment shown in Figure 12, the warp threads 76 contained in the wire mesh are used as the heating element 40. Alternatively, Kanthai wire, among others, can be used as the heating element. The weft thread 78 can consist of a different (even non-conductive) material which, for example, is cheaper and has better thermal conductivity or better adhesive properties than the sorbent material 38. Using the weft wire as a heating thread is also conceivable. Another possible embodiment for heating the wire mesh, in which the weft threads 78 are heated electrically, is shown in Figure 13.The weft thread 78 is designed as a circulating wire and heated.

[0075] The current is fed into and out of the wire mesh from a power source 90 via busbars 74. Alternatively, an embodiment is possible in which both the warp threads 76 and the weft threads 78 are electrically heated. In this case, the intersection points of the warp and weft wires are to be brought into the best possible electrical contact, either by pressing (calendering the wire mesh), by gluing, or by welding.

[0076] Figure 14 shows a flow chart for carrying out a method according to the invention for separating a gas and air humidity, in particular for separating carbon dioxide 70 from the ambient air 11. In a first method step <200> the ambient air 11 is conveyed into the first process chamber 12, 13. In a second process step <210> The ambient air in this first process chamber 12 or the first process chambers 12, 13 is dried until a permissible threshold value for a permissible residual humidity, for example 5% humidity, is not reached. In a subsequent third process step <220> The dried ambient air 11 is passed on to the second process chamber 30. In a fourth process step, the dried ambient air 11 is <230> Carbon dioxide 70 is adsorbed in the sorbent material 38 of the second process chamber 30.If sufficient saturation, in particular complete saturation of the sorption material 38, is achieved, in a fifth process step <240> the second process chamber 30 is evacuated to reduce the residual gas content of ambient air 11 and to prevent possible contamination of the carbon dioxide 70 or to increase the yield of carbon dioxide 70. In a subsequent sixth process step <250> The sorption cells 60 of the first cascade 50 are electrically heated, whereby the carbon dioxide 70 is desorbed from the sorption cells 60 of the first cascade 50. The sorption cells 62, 64, 66, 68 of the subsequent cascades 52, 54, 56, 58 are heated by the waste heat of the heating elements 40 of the first cascade 50 and by the heated gas stream of desorbed carbon dioxide 70.In one process step <260> The heating element 41 of the second cascade 52 is then activated to release the carbon dioxide 70 from the sorption cells 62 of the second cascade 52, wherein the duty cycle of the second heating element 41 is selected to be shorter than the duty cycle of the first heating element 40 for the first cascade 50, with the same heating power. List of reference symbols.

[0077] Plant for the separation of carbon dioxide from the ambient air

[0078] Ambient air first process room first process room

[0079] Adsorption chamber first sorption element first sorbent material

[0080] Supporting frame

[0081] heat exchanger

[0082] Flow generator

[0083] fan

[0084] Pressure reduction unit second process chamber

[0085] Intermediate element second sorption element metallic carrier second sorbent material first heating element second heating element

[0086] pressure sensor

[0087] Temperature sensor

[0088] Gas sensor second flow generator first cascade second cascade third cascade fourth cascade further cascade first sorption cell second sorption cell third sorption cell fourth sorption cell fifth sorption cell

[0089] Carbon dioxide

[0090] Gas flow

[0091] Busbar warp thread

[0092] Weft thread first cascade second cascade third cascade fourth cascade further cascade

[0093] Power source heating mat

[0094] Carbon heating surface Carbon heating fabric Heating wire

[0095] Heating coil first sorption cell second sorption cell third sorption cell fourth sorption cell fifth sorption cell

[0096] Carbon dioxide storage

[0097] Vacuum pump Control device Carrier material Coating Power device Power supply Opening Circumferential surface

Claims

Patent claims 1. A system (10) for separating a gas and / or humidity from the ambient air (11), comprising a flow generator (24) for conveying the ambient air (11) through the system (10), a process chamber (12) for drying the ambient air (11), wherein a first sorption element (16) with a first sorbent material (18) for binding humidity from the ambient air (11) is arranged in the first process chamber (12), and / or a process chamber (30) for separating a gas from the ambient air (11), wherein a sorption element (34) with a sorbent material (38) for separating the gas from the ambient air (11) is arranged in the process chamber (12, 30), characterized in that the sorption element (16, 34) comprises the following: a plurality of heatable sorption cells (60, 62, 64, 66, 68), which are arranged in the flow direction of a gas stream (72) through the process chamber (12, 30) in at least two different cascades (50, 52, 54, 56, 58),and at least two heating elements (40, 41), wherein each cascade (50, 52, 54, 56, 58) is assigned at least one heating element (40, 41), wherein the cascades (50, 52, 54, 56, 58) are serially flowed through by the ambient air (11) such that the waste heat of the sorption cells (60) of the first cascade (50) is transferred to the sorption cells (62) of the second cascade (52).

2. Plant (10) for separating a gas and / or air humidity from the ambient air (11) according to claim 1, comprising a first process chamber (12) for drying the ambient air (11), wherein a first sorption element (16) with a first sorbent material (18) for binding air humidity from the ambient air (11) is arranged in the first process chamber (12), and a second process chamber (30) arranged downstream of the first process chamber (12) in the flow direction for separating a gas from the air in the first process chamber (12) dried ambient air (11), wherein in the second process chamber (30) a second sorption element (34) with a second sorbent material (38) for separating the gas from the ambient air (11) is arranged, wherein the second sorption element (34) comprises a plurality of heatable sorption cells (60, 62, 64, 66, 68) which are arranged in the flow direction of a gas stream (72) through the second process chamber (30) in at least two different cascades (50, 52, 54, 56, 58), and wherein the second sorption element (34) comprises at least two heating elements (40, 41), wherein each cascade (50, 52, 54, 56, 58) is assigned at least one heating element (40, 41), wherein the cascades (50, 52, 54, 56, 58) are serially flowed through by the ambient air (11), such that the waste heat of the sorption cells (60) of the first cascade (50) is transferred to the sorption cells (62) of the second cascade (52).

3. Plant (10) for separating a gas and / or air humidity from the ambient air (11) according to claim 1 or 2, wherein each cascade (50, 52, 54, 56, 58) has a plurality of sorption cells (60, 62, 64, 66, 68), wherein the sorption cells (60, 62, 64, 66, 68) of one cascade are flowed through in parallel and the sorption cells (60, 62, 64, 66, 68) of different cascades are flowed through in series.

4. Plant (10) for separating a gas and / or air humidity from the ambient air (11) according to one of claims 2 or 3, wherein the plant (10) has two or more first process chambers (12, 13), wherein the first process chambers (12, 13) can be flowed through in parallel and the second process chamber (30) is connected downstream of the first process chambers (12, 13).

5. Plant (10) for separating a gas and / or air humidity from the ambient air (11) according to one of claims 2 to 4, wherein a control element is arranged between the first process chamber (12, 13) and the second process chamber (30), with which the gas supply to the second process chamber (30) can be controlled.

6. Plant (10) for separating a gas and / or air humidity from the ambient air (11) according to one of claims 2 to 5, wherein a first flow generator (24) is assigned to the first process chamber (12, 13) and a second flow generator (48) is assigned to the second process chamber (30) in order to convey a gas flow through the respective process chamber (12, 13, 30).

7. System (10) for separating a gas and / or air humidity from the ambient air (11) according to one of claims 1 to 6, wherein each sorption cell (60, 62, 64, 66, 68) of the sorption element (16, 34) has a heating element (40, 41).

8. Plant (10) for separating a gas and / or air humidity from the ambient air (11) according to one of claims 1 to 6, wherein a pressure reduction unit (28) for generating a negative pressure in the second process chamber (30) is arranged on the process chamber (12, 30).

9. Plant (10) for separating a gas and / or humidity from the ambient air (11) according to one of claims 1 to 8, wherein the sorbent material (18, 38) is a physical sorbent material.

10. Plant (10) for separating a gas and / or humidity from the ambient air (11) according to one of claims 2 to 9, wherein the second process chamber (30) is connected to a carbon dioxide storage (110).

11. System (10) for separating a gas and / or air humidity from the ambient air (11) according to one of claims 2 to 10, wherein a temperature sensor (44), a pressure sensor (42) and / or a gas sensor (46) for detecting a gas concentration is arranged on the second process chamber (30).

12. System (10) for separating a gas and / or air humidity from the ambient air (11) according to one of claims 1 to 11, wherein the system (10) has a control device (114) for controlling the flow generator (24) and the at least two heating elements (40, 41).

13. System (10) for separating a gas and / or humidity from the ambient air (11) according to one of claims 1 to 12, wherein the heating elements (40, 41) are designed as heating coils (99) or as heating mats (92).

14. A method for separating a gas and / or humidity from the ambient air (11) with a system (10) according to one of claims 2 to 13, comprising the following steps: Conveying the ambient air (11) into the first process chamber (12, 13), Drying the ambient air (11), Passing the dried ambient air (11) into the second process chamber (30), - Adsorbing the gas contained in the dried ambient air (11) in the second sorbent material (38) of the sorption cells (60, 62, 64, 66, 68), Evacuating the second process chamber (30), Desorbing the gas (70), wherein firstly the heating element (40) of the first cascade (50) is activated in order to release the gas from the sorption cells (60) of the first cascade (50), and subsequently the heating element (41) of the second cascade (52) is activated in order to release the gas from the sorption cells (62) of the second cascade (52).

15. The method according to claim 14, wherein the sorption cells (60, 62, 64, 66, 68) are heated to a target temperature of 140°C to 220°C.

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