Modular gas separation method, modular gas separation device system, and modular gas separation device

Abstract

The invention relates to a modular gas separation method for obtaining products from ambient air by means of modules of a modular gas separation device system, comprising drawing in a raw gas from the ambient air and separating O2 as a first product, N2 as a second product and CO2 as a third product from the raw gas, wherein the products are separated using one or more adsorption processes in order to provide the first product, the second product and / or the third product for further use, wherein the method can be adapted such that the products can be provided in a desired purity, in a desired amount and / or in a desired composition, and the adsorption processes include pressure-swing adsorption processes. The invention also relates to a gas separation device system for using the gas separation method and to a gas separation device based on the gas separation device system.

Description

[0001] Description

[0002] “Modular gas separation process, modular gas separation device system and modular gas separation device”

[0003] The invention relates to a process for extracting technical gases from the ambient air and a modular device for implementing this process.

[0004] Background of the invention

[0005] Due to the costs associated with making industrial gases available on the market and the risk of shortages or disruption of supply chains, it is advantageous to enable industrial companies to extract technical gases, in particular dioxygen, dinitrogen and carbon dioxide, locally and in the required quantity and type from the ambient air using a suitable process and device.

[0006] Pressure swing adsorption (PSA) is a physical process for separating gas mixtures under pressure using a porous adsorbent material. Adsorption describes the ability of gases, liquids, or dissolved solids to attach to the surface of a solid. The separation of a gas mixture is based on one of two known physical principles. The first is separation due to equilibrium adsorption. Different gases have varying degrees of tendency to attach to certain solids. Molecules that attach to a surface tend to detach from that surface again due to thermal molecular motion.Depending on the nature of the surface and the gas molecules, an equilibrium is established in which an equal number of gas molecules attach to and detach from the surface over a period of time, so that the total number, or concentration, of molecules attached to or adsorbed on the surface at a given time remains constant. Equilibrium adsorption takes advantage of the fact that this equilibrium is established for different gases at different concentrations under the same conditions. Thus, one of the components to be separated is adsorbed more strongly than another, resulting in an enrichment of the less well-adsorbed component in the gas phase.

[0007] The second principle is separation based on the molecular sieve effect. A molecular sieve is a porous material that is less easily penetrated by molecules above a certain size. A second gas in the gas mixture, with a smaller molecular size, penetrates the porous structure of the sorbent material more quickly. When a gas mixture flows through sorbent material in a reactor bed, the molecules and atoms that are less able to penetrate the pores require less time to pass by, thus reaching the reactor bed exit in higher concentrations.

[0008] Processes that utilize one of these two principles allow the separation of gas mixtures. In a separation process, in a first process step, a gas mixture consisting of several components (gases) is introduced under elevated pressure (approx. 6-10 bar) or at higher working pressures into the inlet of a reactor filled with sorbent material (also known as a reactor bed or sorbent bed), so that the gas mixture flows through the sorbent material. One or more components of the mixture are preferentially adsorbed onto the sorbent material (also known as the "heavy component"). The non-preferentially adsorbed component (also known as the "light component") can be removed at a first outlet of the reactor bed. After a certain amount of gas mixture has been introduced into the reactor bed, a situation arises in which the sorbent material has adsorbed a concentration of the heavier component such that further adsorption is no longer possible.The reactor bed is then saturated and part of the heavy component exits at the first outlet in addition to the light component.

[0009] Regeneration can occur in a second process step. For this, the first outlet for the light component is closed and a second outlet for the heavy component is opened. This is accompanied by a rapid pressure drop. The lower pressure causes the adsorbed gas to be desorbed again and can be tapped off at the second outlet.

[0010] Variations of the PSA technique involve the use of a vacuum pump to achieve larger pressure differences between the first and second process steps. In this case, the method can also be referred to as VSA (Vacuum Swing Adsorption). When the working pressures are above or below atmospheric pressure, it can be referred to as VPSA (Vacuum Pressure Swing Adsorption). The process can also take advantage of the different behavior of gases and sorbent materials at higher temperatures. In this case, it is also referred to as TSA (Temperature Swing Adsorption).

[0011] Conventional air separation plants operate with two pressure vessels, which prevents a consistent and continuous nitrogen discharge, resulting in a significant interruption in the production flow. To ensure a consistent discharge, both a compressed air storage vessel upstream of the pressure vessels and a gas storage vessel downstream of the pressure vessels must be installed.

[0012] A conventional pressure swing adsorption system for separating oxygen from ambient air is described, for example, in DE 102012 010292 A1. Such a pressure swing adsorption system consists of two pressure vessels, a compressed air supply, a compressed air storage vessel, and a gas storage vessel. Oil-free, clean compressed air flows from a compressed air supply into the compressed air storage vessel and from there through one of the two pressure vessels, depending on the position of the inlet valves.

[0013] EP 3 613492 A1 describes a process for separating O2 from N2 and / or Ar from air. The process uses at least five adsorption beds comprising kinetically selective adsorbents for O2. The adsorption and enrichment of CO2 is not mentioned. Patent Literature 2 mentions a pressure swing adsorption system for exclusively separating N2 and O2 from a gas mixture.

[0014] The pressure swing adsorption plant of EP 2 365 860 B1, which also consists of only two parallel adsorbers, is suitable for the production of oxygen from the air and is characterized by very short cycle times and lower energy consumption.

[0015] US 6 171 371 B1 describes a pressure swing adsorption process based on two pressure vessels for separating O2 and N2 from air with additional use of vacuum.

[0016] EP 0 705636 B1 describes a process for oxygen production based on the cooperation of pressure swing adsorption nitrogen production and chemical air separation (GLAS - Chemical Looping Air System). In the described process, compressed air is introduced into a PSA system to adsorb O2, CO2, and moisture to obtain N2 with a purity of > 95%. The adsorbed components are removed by pressure build-up and pressure reduction to atmospheric pressure to form oxygen-enriched residual gas (28-32% O2) and regenerate the adsorbent. The PSA-desorbed, oxygen-enriched residual gas is fed to a CLAS system to complete oxygen absorption. However, this is not a pure PSA process; it is combined with chemical air separation.

[0017] Conventional processes include, in particular, the separation of N2 and O2 from air and the extraction of pure N2 and O2 using pressure swing adsorption.

[0018] In contrast, conventional processes involve the separation and concentration of CO2 from industrial exhaust streams. For example, EP 2 861 325 B1 describes a process for producing high-purity N2 and CO2 from a hot exhaust stream (T = 400-500°C).

[0019] An object of the present invention is to provide a gas separation process that allows the optimized separation of N2, O2, and CO2 from the ambient air by means of pressure swing adsorption and makes them available as industrial gases. A further object of the present invention is to provide a device system capable of implementing the gas separation process according to the invention locally and in the quantity and type of industrial gases as required.

[0020] This object is achieved by the gas separation method according to the invention according to independent claim 1, a module set for a gas separation device according to claim 7, a gas separation device system according to claim 8, a device module set according to claim 14 and a gas separation device according to claim 15.

[0021] Further advantageous embodiments of the invention emerge from the subclaims and the following description of preferred embodiments of the present invention.

[0022] In the following, according to common practice, the term "N2" refers to the chemical compound dinitrogen, the term "O2" to the chemical compound dioxygen, and "CO2" to the chemical compound carbon dioxide. Furthermore, "H2" refers to the chemical compound dihydrogen, and "Ar" to the chemical element argon. The physical state of the respective compound can vary between gaseous and liquid. Compounds containing isotopes of the elements other than the most common ones present in the above-mentioned compounds are included in the name of the compound. Other chemical compounds are specified analogously in formula notation, according to common practice.A modular gas separation process according to the invention for obtaining products from ambient air by means of modules of a modular gas separation device system comprises sucking in a raw gas from the ambient air and separating O2 as a first product, N2 as a second product and CO2 as a third product from the raw gas, wherein the separation of the products takes place by one or more adsorption processes in order to make the first product, the second product and / or the third product available for further use, wherein the process can be adapted such that the products can be made available in a desired purity, in a desired amount and / or in a desired composition, and the adsorption processes include pressure swing adsorption processes.

[0023] The modular gas separation process according to the invention makes it possible, in addition to the classic compressed air treatment, to also obtain corresponding technical gases such as CO2, N2, O2 but, in certain embodiments, also other gases such as Ar, H2, etc. by using a production line.

[0024] An adsorption process involves passing a gas, such as a raw gas, through a sorbent material contained in a container. The container can also be referred to as a reactor bed, sorbent bed, or bed. A piping system containing a reactor bed and designed to carry out an adsorption process can also be referred to as a column. A device for carrying out, for example, a pressure swing adsorption process (PSA process) can be referred to as a PSA unit or an adsorption device. A PSA unit can comprise several columns. A column can contain sorbent materials, whereby the sorbent materials are physically contained in the reactor bed contained in the column. Sorbent materials are materials that exert an adsorption effect on gases or gas molecules that come into contact with them.

[0025] Sorbent materials within the meaning of the present disclosure include, for example, physical sorbent materials such as zeolites, silica materials, MOF (Metal Organic Framework), activated carbon, COF (Covalent Organic Framework), carbon molecular sieves, materials based on alkali metals / metal oxides, ordered porous carbon, ACF (Activated Carbon Fibers), graphene, CMS (Carbon Molecular Sieve), and others, and their composites. Furthermore, sorbent materials within the meaning of the present disclosure include chemical sorbent materials such as composite adsorbents produced by impregnation with K2CO3, binary eutectic mixtures (KNO3 and UNO3), NaNCh, Al2O3, ZrO2, TiO2, MnO2, ZnO, and others. By separating the required technical gases from the ambient air, the production of the technical gases can be ensured at the point of consumption, thus eliminating the need for a costly supply network and its associated costs.In particular, transport costs and personnel costs can be reduced.

[0026] By using the basic principle of pressure swing adsorption, the necessary compressed air treatment can be provided and corresponding technical gases can be optimally extracted from compressed air or another environment.

[0027] There are embodiments in which the adsorption processes also include temperature swing adsorption and temperature-pressure swing adsorption. In contrast to pressure swing adsorption processes, which rely on manipulating the adsorption effect of sorbent materials by changing the pressure in a sorbent bed, in temperature swing adsorption processes the adsorption effect of sorbent materials can be manipulated by changing the temperature in a sorbent bed. Due to the lower energy requirement associated with temperature swing adsorption, the process can be adapted to the prevailing energy availability at the point of use. In temperature-pressure swing adsorption processes, the adsorption effect is manipulated by changing both the pressure and the temperature, which allows for more effective gas separation.By using adsorption processes, which largely operate without the material consumption associated with chemical gas separation processes, procurement costs can be reduced.

[0028] There are embodiments in which treated raw gas is made available as a product for further use. Treated raw gas can be raw gas that is drawn in by an intake device, cleaned of particles, dust, and / or soot using a filter or air cleaner, dehumidified using a dehumidification device, and compressed using a compressor. Thus, industrial gases and compressed air can be provided for a variety of technical applications using the same process. Even if no industrial gases are needed at a given time, the intake of ambient air can provide useful products.

[0029] There are embodiments in which the separation of the products from the raw gas comprises generating a reduced raw gas by separating O2 and N2 from the raw gas and subsequently separating CO2 from the reduced raw gas. Sequential separation of the products in consecutive separation processes can improve the separation of gases with naturally low concentrations in the ambient air. For example, the natural concentration of N2 in the atmosphere is approximately 78%, the natural concentration of O2 is approximately 21%, and the natural concentration of CO2 is less than 1%. By first separating N2 and O2 from the raw gas obtained from the ambient air, the concentration of the resulting reduced raw gas is greatly increased, thereby increasing the efficiency and energy efficiency of the CO2 separation.

[0030] There are embodiments in which the separation of O2 and N2 from the raw gas occurs simultaneously. This can be achieved, for example, by parallel separation processes for N2 and O2.

[0031] There are embodiments in which additional products containing H2 or Ar are obtained. By separating the most abundant components of the raw gas extracted from the ambient air, N2 and O2, the abundance of trace gases such as H2 and Ar in the reduced raw gas is increased, which can thus also be separated using appropriate processes and made available locally.

[0032] A module set according to the invention for a gas separation device for implementing the gas separation process according to the invention comprises a compressed air treatment module and an adsorption module set, which comprises a first adsorption module for separating N2, a second adsorption module for separating O2 and a third adsorption module for separating CO2.

[0033] A modular gas separation device system for carrying out the gas separation process according to one of claims 1 to 6 comprises the module set for a gas separation device, wherein the compressed air treatment module comprises a filter device, a compressor, a dryer unit, and a compressed air reservoir, and each adsorption module of the adsorption module set includes an adsorption device, a gas line device, a connection device, and control electronics. The adsorption module for recovering N2 can be a first adsorption module, the adsorption module for recovering O2 can be a second adsorption module, and the adsorption module for recovering CO2 can be a third adsorption module, which together are adsorption modules.

[0034] The adsorption modules are to be designed so that they are functional in various combinations of different adsorption modules. A combination can, for example, be a device that contains a compressed air treatment module, an adsorption module for extracting N2 (e.g., a first adsorption module), and an adsorption module for extracting CO2 (e.g., a third adsorption module).

[0035] Yet another combination can be a device which contains a compressed air treatment module, an adsorption module for the production of O2, for example a second adsorption module, and an adsorption module for the production of CO2, for example a third adsorption module.

[0036] A further combination may be a device that contains a compressed air treatment module, an adsorption module for extracting N2, for example, a first adsorption module, and an adsorption module for extracting O2, for example, a second adsorption module. A further combination may be a device that contains a compressed air treatment module, an adsorption module for extracting N2, for example, a first adsorption module, and an adsorption module for extracting O2, for example, a second adsorption module.

[0037] Furthermore, a further combination can be a device that contains a compressed air treatment module and an adsorption module for extracting CO2, for example, a third adsorption module. Further combinations, including those for extracting other products, are possible according to the invention.

[0038] A combination can also be referred to as a production line. Each module comprises components that enable gas storage, such as pipelines, which can also be referred to as gas lines or pipes, or gas storage units, which can also be referred to as gas tanks, tanks, or reservoirs. A storage unit can also be a compressed air storage unit or a product storage unit.

[0039] Each adsorption module comprises, in particular, one or more product reservoirs. A reservoir is a container that can hold a gas at a pressure above, equal to, or below the ambient air. Each module comprises components that allow gas flow regulation, such as valves, connectors, or the like. In particular, connectors are connecting devices that can be connected to a pipeline and through which gases or substances can be conducted from the outside into the module and out of the module. Each module can comprise sensors, for example, gas sensors. Each module can comprise control electronics.

[0040] Each module can contain components that can receive and interpret control signals from an external circuit. Each module can optionally contain a device that allows a user to control the process performed by the module. Each module can contain air filters for removing dust, soot, or other foreign matter from gas. Each module can contain compressors for increasing the pressure of gases. Each module can contain dryer units for removing water or water vapor from gas.

[0041] Depending on requirements, various modules can be combined, including initial compressed air treatment, for example, using the compressed air treatment module, and compression of the raw gas to, for example, 7 bar, although higher or lower pressures are possible. After compressed air treatment, the raw gas is passed on in stages through the adsorption columns under appropriate control. Through modular combination, a production line can be provided to meet local demand for industrial gases, such as N2, O2, and CO2, in the required concentration, quantity, and purity.

[0042] The sorbent beds in adsorption modules for N2 recovery can be filled with activated carbon and / or carbon granules. The sorbent beds in adsorption modules for O2 recovery can be filled with zeolites. In sorbent beds in adsorption modules for N2 recovery, O2 and CO2 molecules are adsorbed by the activated carbon under fluid pressure, and N2 can flow into the product storage as a product. In sorbent beds in adsorption modules for O2 recovery, zeolite adsorbs the N2 molecules, and O2 can flow into the product storage as a product. The flow rate influences the concentration of the remaining gas mixture, which can be tapped off from the producing sorbent bed.

[0043] Embodiments are also possible in which at least one of the adsorption modules comprises a vacuum pump. By means of a vacuum, for example, generated by a vacuum pump, the desorption phase in a sorbent bed can be extended, thus more effectively removing the heavier component from the sorbent bed. There are embodiments in which each adsorption module of the adsorption module set is designed to further process a reduced raw gas from another adsorption module arranged in series, wherein the reduced raw gas is generated by separating at least one of O2, N2, or CO2 from the raw gas.

[0044] A reduced raw gas is a raw gas from which one or more gas components have been removed. For example, raw gas has the composition of ambient air, singly reduced raw gas has the composition of ambient air with a reduced proportion of O2, N2, or CO2, and doubly reduced raw gas has the composition of ambient air with a reduced proportion of two of O2, N2, or CO2. Each adsorption module can be configured to further process reduced raw gas from any other adsorption module to separate additional products from the raw gas in successive process steps.

[0045] There are embodiments in which each module has an external casing and / or an internal structure. By keeping each module in its own casing, with a self-contained mechanical structure, the service life of the module components can be extended by minimizing external influences. Furthermore, the module shape can be designed to be compact, allowing for easier transport and installation at the destination. An internal structure is a frame or scaffold to which the components that make up the module are attached, particularly in adsorption modules, the adsorption devices. Compact process technology allows for greater flexibility in adjusting the purity of the required gases. Furthermore, the process can be more efficient in terms of energy balance.

[0046] There are embodiments in which the gas separation system further comprises one or more separation modules designed to recover further products comprising H2 or argon. The separation modules can be designed in which the further products are separated from the reduced raw gas by further applying suitable adsorption methods. Alternatively, embodiments are conceivable in which the further products are recovered from the reduced raw gas using other processes, for example membrane processes, distillation processes, chemical separation processes, or other suitable processes. These separation processes can further include centrifugal processes, which separate different gases by different densities, or cryogenic or refrigeration processes, which, for example, utilize different condensation temperatures of different gases, or membrane processes.The separation modules can separate further products from a raw gas or reduced raw gas from which N2, O2 or CO2 have already been separated by the adsorption modules.

[0047] There are embodiments in which each adsorption device comprises two columns, which are designed to carry out one of the adsorption processes in parallel to one another in order to generate a continuous product flow. By providing two columns in an adsorption module, a continuous product stream can be generated. An adsorption device can be referred to as a PSA unit. This can be achieved by having one column go through the adsorption phase while a second column goes through a desorption or regeneration phase. When the adsorption phase reaches saturation, which can be determined by measurement using appropriate sensors, e.g. using a gas measuring device, the first column is transferred from the adsorption phase to the desorption phase and the second column is transferred from the desorption phase to the adsorption phase by a control system.In addition, in order to expel the supernatant of desorbed heavy component from the sorbent bed, a portion of the product can be used to rinse the bed to avoid contamination.

[0048] There are embodiments in which at least one adsorption device is configured for purity adjustment. Purity adjustment can be achieved by measuring the concentration of a preferentially adsorbed component, i.e., a heavier component, at the outlet of a sorbent bed in an adsorption phase. As soon as a corresponding concentration is measured, the column containing the sorbent bed is transferred to the desorption phase.

[0049] A device module set according to the invention for extracting products from ambient air comprises a compressed air treatment module and at least one of the modules of the adsorption module set. A gas separation device according to the invention for extracting products from ambient air comprises the device module set. By combining various adsorption modules with at least one compressed air treatment module, a gas separation device can be realized based on the modular gas separation device system that is designed to meet the local demand for industrial gases comprising at least one of N2, O2, and CO2. Demand can be met in the required quantity, purity, and composition from the ambient air. Embodiments of the invention will now be described by way of example and with reference to the accompanying drawing, in which:

[0050] Fig. 1 schematically shows three embodiments of a gas separation process according to the invention and devices according to the gas separation device system according to the invention;

[0051] Fig. 2 shows a schematic detailed representation of a device according to the gas separation device system according to the invention in an embodiment with two modules; and

[0052] Fig. 3 schematically shows a detailed representation of a device according to the gas separation device system according to the invention in an embodiment with four modules.

[0053] The method and device according to the invention are explained below with reference to the figures. Unless otherwise stated, a method according to the invention is understood to mean the method performed by the device shown in each case. The verb "connected" is understood to mean a pipeline connection designed to allow a gas or liquid to flow from a first component, assembly, or part to a second component, assembly, or part that is connected to the first component, assembly, or part.

[0054] A first exemplary embodiment of a gas separation process according to the invention and of a gas separation device 10 according to the gas separation device system according to the invention for carrying out the process is shown in Fig. 1a). The device comprises a compressed air treatment module 11, a first adsorption module 12 for producing N2, including purity adjustment, and a second adsorption module 13 for producing O2, including purity adjustment. The modules—here the compressed air treatment module 11, the first adsorption module 12 for producing N2, including purity adjustment, and the second adsorption module 13 for producing O2, including purity adjustment—are to be understood according to the invention as self-contained components that can be connected to one another in different ways as required.

[0055] In the embodiment shown in Fig. 1a), the compressed air treatment module 11 first draws in ambient air. The task of the compressed air treatment module 11 is to treat the drawn-in raw gas for further processing. The treatment may include filtering by passing it through a filter device to remove solids such as dust or soot particles and the like, thus producing a filtered raw gas.

[0056] The treatment may also include optional drying of the raw gas to remove water molecules. Drying can be performed using a suitable drying device that removes water molecules from the raw gas using a drying process. The drying process can, for example, be a membrane process that involves passing through a hollow-fiber membrane or similar. The drying process can also be an adsorption process or a condensation process. Drying produces a dried raw gas.

[0057] The treatment also includes compression of the raw gas using a compression device, such as an axial compressor. Compression can occur before or after drying. Compression produces compressed raw gas. Suction, filtering, drying, and compression together represent treatment processes.

[0058] There are embodiments in which other processing processes are provided in addition to those mentioned. The compressed raw gas can also be referred to as processed raw gas. The compressed air processing module 11 can further comprise one or more compressed air reservoirs in which the processed raw gas is temporarily stored to be available for subsequent processing steps. The compressed air processing module 11 further comprises connection devices by means of which the processed raw gas can be discharged from the compressed air processing module 11. The connection devices can be designed to be closable. The compressed air processing module 11 can further comprise discharge devices for the waste products of the processing processes.

[0059] In the following, first adsorption modules, second adsorption modules, etc. are understood as embodiments of adsorption modules in general.

[0060] In the exemplary embodiment shown in Fig. 1 a), the treated raw gas provided by the compressed air treatment module 11 is further processed by the first adsorption module 12. For this purpose, the treated raw gas can be introduced into the first adsorption module, for example, via a pipeline provided for this purpose. The first adsorption module 12 shown here as an example comprises an adsorption device which extracts N2 from the treated raw gas using an adsorption process. The adsorption device comprises one or more, for example two, reactor beds which are filled with a suitable sorbent material and which can be loaded with the raw gas. According to the exemplary embodiment shown in Fig. 1 a), the adsorption device comprised by the first adsorption module 12 is designed such that a degree of purity can be adjusted.Depending on the selected purity setting, N2 can be extracted as the first product with the selected purity level from the treated raw gas. According to a process such as that described below, the first adsorption module 12 extracts N2 from the treated raw gas.

[0061] The first adsorption module 12 can comprise a tank in which the recovered N2 is stored as the first product. The processed raw gas, which has been reduced by one product, here, for example, N2 of the selected purity, can be referred to as singly reduced raw gas. Since the ambient air from which the processed raw gas was obtained consists of approximately 78% (molar fraction) N2, the molar fraction of those components that are not N2 in singly reduced raw gas is proportionally higher than in the ambient air. By using a raw gas that is not similar to the processed raw gas as the starting point for further processing steps, but rather a singly or multiply reduced raw gas, the efficiency of gas recovery and the energy efficiency of gas recovery in subsequent adsorption processes can be increased.

[0062] Embodiments are possible in which an adsorption module according to the invention, similar to the first adsorption module 12 shown here as an example, is not loaded with processed raw gas, but with singly or multiply reduced raw gas that has already been processed by other adsorption modules according to the invention. The raw gas, which has been singly reduced here, for example, is then further processed in a second adsorption module 13.

[0063] The second adsorption module 13 shown here as an example comprises an adsorption device which recovers O2 from the singly reduced raw gas by means of an adsorption process. The adsorption device comprises one or more, for example two, reactor beds which are filled with a suitable sorbent material and which can be loaded with the raw gas. According to the exemplary embodiment shown in Fig. 1 a), the adsorption device comprised by the second adsorption module 13 is designed such that a purity level adjustment can be carried out. Depending on the selected purity level adjustment, O2 can be recovered as a second product with the selected purity level from the singly reduced raw gas. According to a process such as that described further below, the second adsorption module 13 recovers O2 from the singly reduced raw gas.The second adsorption module 13 can comprise a tank in which the recovered O2 is stored as a second product. The singly reduced raw gas, which has been reduced by one product, here for example O2 of the selected purity, can be referred to as doubly reduced raw gas. Since the molar fraction of O2 in the singly reduced raw gas is higher than that of the ambient air, the molar fraction of those components that are not O2 is proportionally higher in doubly reduced raw gas compared to singly reduced raw gas. Each adsorption module 12, 13 comprises connection devices by means of which the product and the reduced raw gas can be discharged from the adsorption module. In particular, in doubly reduced raw gas, which is identified here as the third product, the molar fraction of CO2 is significantly higher than that of the ambient air. A gas separation device 10 according to the invention, which operates according to the gas separation process according to the invention and is shown in Fig.1a) produces N2 as the first product, O2 as the second product and a gas mixture containing a greatly increased molar fraction of CO2 as the third product.

[0064] A second exemplary embodiment of a gas separation process according to the invention and of a gas separation device 10 according to the gas separation device system according to the invention for carrying out the process is shown in Fig. 1b). The device comprises the compressed air treatment module 11, the first adsorption module 12 for obtaining N2 including purity adjustment, the second adsorption module 13 for obtaining O2 including purity adjustment, and a third adsorption module 14 for obtaining CO2 including purity adjustment. The raw gas is processed identically to the exemplary embodiment shown in Fig. 1a), but the twice-reduced raw gas is further processed in the third adsorption module 14. The third adsorption module 14 shown here as an example comprises an adsorption device which extracts CO2 from the twice-reduced raw gas using an adsorption process.The adsorption device comprises one or more, for example two, reactor beds filled with a suitable sorbent material and which can be loaded with the raw gas. According to the exemplary embodiment shown in Fig. 1 b), the adsorption device comprised by the third adsorption module 14 is designed so that a purity level adjustment can be carried out. Depending on the selected purity level adjustment, CO2 can be obtained as a third product with the selected purity level from the doubly reduced raw gas. According to a method, for example, as described further below, the third adsorption module 14 recovers O2 from the doubly reduced raw gas. The third adsorption module 14 can comprise a tank in which the recovered CO2 is stored as a third product.The singly reduced raw gas, which has been reduced by one product—here, for example, CO2 at the selected purity—can be referred to as triple-reduced raw gas. Since the molar fraction of CO2 in the doubly reduced raw gas is higher than in the ambient air, the molar fraction of those components that are not CO2 is proportionally higher in the triple-reduced raw gas compared to the singly reduced raw gas. The triple-reduced raw gas thus produced then has, for example, a higher concentration of argon, which can be obtained in subsequent process steps, for example, as a fourth product.

[0065] A system designed according to the embodiments becomes more efficient because gas separation has already taken place in the compressed air treatment module 11, which can lead to a higher selectivity of the gas separation in the first adsorption module 12.

[0066] A third exemplary embodiment of a gas separation process according to the invention and a gas separation device 10 according to the gas separation device system according to the invention for carrying out the process is shown in Fig. 1c). The device comprises the compressed air treatment module 11 and the third adsorption module 14 for CO2 recovery, including purity adjustment. Here, CO2 is recovered as the third product directly from the treated raw gas.

[0067] The exemplary embodiments described above are merely exemplary of possible combinations of the gas separation devices 10 provided by the gas separation device system according to the invention. Embodiments are conceivable in which the modules according to the invention are provided in other combinations than those shown here, in a different sequence, serially, or in parallel to one another, in order to produce the desired product combination and / or a desired concentration and / or a desired quantity of the product gases. Such a combination can also be referred to as a production line. A modular structure according to the invention allows the gas separation process to proceed optimally.

[0068] A fourth exemplary embodiment of a gas separation process according to the invention and a gas separation device 10 according to the gas separation device system according to the invention for carrying out the process is shown schematically in greater detail in Fig. 2). The exemplary embodiment shown here is, for example, analogous to the exemplary embodiment shown in Fig. 1c). A gas separation device 10 according to the invention can comprise two modules. In the exemplary embodiment shown here, one module is the compressed air treatment module 11, and one module is the third adsorption module 14 for the recovery of CO2, including purity adjustment.The compressed air treatment module 11 consists of an intake point with a filter device 111, which removes dust particles from the air, a compressor 112, a dryer unit 113, and an air reservoir 114, in which the compressor continuously compresses the sucked-in ambient air to a preset pressure. The preset pressure can be, for example, 7 bar. Additional fittings such as valves, water separators 115, etc. can be attached to the air reservoir 114. On an upper side of the air reservoir 114, a line 116 is formed, with which treated raw gas, which is not intended for further processing by the gas separation device 10, can be transported to external consumers. The treated raw gas is fed to the third adsorption module 14 via a further line 117. The adsorption module 14 can be designed in different ways.In the embodiment shown here, the adsorption module 14 includes a primary stage 141 and a secondary stage 142. A residual dehumidification unit 143, which further dehumidifies the air using various drying agents, such as silica gel, aluminum oxide compounds, etc., can optionally be installed upstream of the primary stage 141. The use of a residual dehumidification unit 143 ensures that the gas used to extract CO2 has the lowest possible residual moisture content, thereby protecting the sorbent materials used from water absorption. In the present embodiment, a product reservoir 144 is formed on the secondary stage, to which a high-pressure compressor including bundle 145 is optionally connected.The extracted CO2, which is stored in the product reservoir 144, is then either forwarded to the external consumer via a line 146 or compressed in a bundle using a high-pressure compressor 147 to, for example, 150 bar. The primary stage 141 contains a PSA unit 148, which is designed accordingly and can operate completely independently of the compressed air treatment module 11. The PSA unit contains two separately regulated and controlled columns 149, 1410, which in turn contain lines, valves, sensors, etc.

[0069] The operation of the primary stage 141 is designed for continuous operation, so that the first column 149 undergoes an adsorption phase, while simultaneously the second column 1410 undergoes a desorption or regeneration phase. When the adsorption phase has reached saturation in the first column 149 or in the second column 1410, which can be determined by measurement using appropriate sensors, for example, a gas measuring device, a control system transfers the first column 149 from the adsorption phase to the desorption phase, and the second column 1410 from the desorption phase to the adsorption phase. Both columns 149 and 1410 are filled with a sorbent material or with a formulation composed of several types of sorbent material. According to the invention, the sorbent material is flowed through or wetted with dried raw gas from bottom to top.While the adsorption, i.e. in the present embodiment the binding of the CCh molecules, takes place by means of the sorbent material, the remaining volume flow is forwarded from the first column 149 through a central compressed air line 1411 to the external consumer with the aid of the switching of valves provided for this purpose.

[0070] It must be ensured that unwanted backflow along the working section is prevented, which can be achieved, for example, by alternating the valves or check valves. The air reservoir 114 is, in particular, a reservoir suitable for storing gases at pressures that are high compared to the ambient pressure. The air reservoir 114 can therefore also be referred to as a compressed air reservoir 114. In particular, the light component (here N2, O2, etc.) is to be understood as residual gas. It is returned to the central compressed air line 1411. The heavy component, which was obtained as CO2 in the primary stage, is passed on to the secondary stage 142. Alternating between the first column 149 and the second column 1410, a continuous separation of CO2 from the raw gas and a recovery of CO2 takes place. CO2 selectivity can be provided in the primary stage 141.The adsorption process can include an adsorption phase alternating between the first column and the second column, in which a pressure of up to 6 bar is used. The pressure in the desorption phase can, for example, be between 1 bar and 0.001 bar.

[0071] The secondary stage 142 can comprise a first column 1414 and a second column 1415. Various embodiments for the secondary stage 142 are conceivable. For example, a further separation station (not shown) can be provided, which allows the separation of undesirable gas components (residual O2, N2, etc.). This separation can be less complex than the separation of pure ambient air. Furthermore, the system can provide for the use of processes that differ from the adsorption process. For example, membrane processes, etc., can be provided, with which a desired degree of purity of CO2, for example from 2.0 to 5.0, can be set. Optionally, a vacuum pump 1413 can be provided, with which a negative pressure can be generated in both columns 1414 and 1415. Further embodiments are conceivable with which the recovery of CO2 can be accelerated.For example, the secondary stage can be designed to carry out a variothermal process TSA (temperature swing adsorption) and / or TPSA (temperature pressure swing adsorption), with which the CO2 recovery can be improved. In addition, an integrated heating element (not shown) for controlling the temperature of the sorbent material can be provided at positions 149a and 1410a. The heat used by the heating element can be obtained from various sources. For example, the use of waste heat from the compressors by means of heat exchangers or electrical reheating is conceivable. Further embodiments can provide that the columns 1414 and 1415 are filled with a sorbent material that binds only unwanted gas molecules, thereby allowing a further increase in the degree of purity. In the secondary stage 142, a purity of the CO2 recovery can be adjustable from 2.0 to 5.0.Downstream selectivity technologies can be used. In particular, electrochemical catalysts, hollow-fiber membrane technology, and similar technologies can be used as downstream selectivity technologies.

[0072] A fifth exemplary embodiment of a gas separation process according to the invention and of a gas separation device 10 according to the gas separation device system according to the invention for carrying out the process is shown schematically in greater detail in Fig. 3. The gas separation device shown in Fig. 3 comprises four modules. The first module is the compressed air treatment module 11, the second module is the first adsorption module 12, the third module is the second adsorption module 13, and the fourth module is a second embodiment of the third adsorption module 14, which is referred to below as the third adsorption module 16. Here, the first adsorption module 12 is designed for the recovery of N2, the second adsorption module 13 is designed for the recovery of O2, and the third adsorption module 16 is designed for the recovery of CO2.

[0073] The compressed air treatment module 11 consists of an intake point with a filter device 111, which removes dust particles from the air, a compressor 112, a dryer unit 113, and an air reservoir 114, in which the compressor continuously compresses the sucked-in ambient air to a preset pressure. The preset pressure can be, for example, 7 bar. Additional fittings such as valves, water separators, etc. 115 can be attached to the air reservoir 114. A second air reservoir 114a can be provided parallel to the air reservoir 114. In the embodiment shown here, the second air reservoir 114a is connected via a separate circuit, which ensures that both air reservoirs 114, 114a can operate independently of one another. Additional fittings such as valves, water separators 115 can be attached to the air reservoir.On the upper side of the air reservoir 114a, a line 116 is formed, by which treated raw gas, which is not intended for further processing by the gas separation device 10, can be transported to external consumers. Consequently, the raw gas stored in the air reservoir 114a is intended for forwarding to the external consumers. Treated raw gas is forwarded to the first adsorption module 12 via a further line 117. The line 117 is not connected to the air reservoir 114a. In the inventive method described here, the compressed air treatment module 11 represents a first stage in which the raw gas sucked in from the ambient air is treated. In the inventive method described here, the first adsorption module 12 represents a second stage in which N2 is extracted from the treated raw gas.A residual dehumidification unit 118 can optionally be provided between the compressed air treatment module 11 and the first adsorption module 12 in order to remove any water residues from the treated raw gas before further processing.

[0074] The first adsorption module 12 includes a PSA unit 121 and a product storage tank 122, which, in the exemplary embodiment presented here, is intended for the storage of N2. According to the invention, the PSA unit 121 and the first adsorption module 12 are designed such that they can operate independently and autonomously from other modules, in particular from the compressed air treatment module 11 and other adsorption modules, i.e., they can carry out the adsorption process. The PSA unit includes a first column 123 and a second column 124, which can be controlled and operated separately from one another, with lines, valves, sensors, and other components being provided accordingly. The operation of the first adsorption module 12 is designed for continuous operation, so that the first column 123 undergoes an adsorption phase, while the second column 124 simultaneously undergoes a desorption or regeneration phase.When the adsorption phase has reached saturation, here for example with O2 and CO2, in the first column 123 or in the second column 124, which can be determined by measurement using appropriate sensors, for example a gas measuring device, the first column 123 is transferred from the adsorption phase to the desorption phase and the second column 124 is transferred from the desorption phase to the adsorption phase by means of a control system.

[0075] Both columns 123 and 124 are filled with a sorbent material or with a formulation composed of several types of sorbent material. According to the invention, the sorbent material is flowed through or wetted with dried raw gas from bottom to top. While the adsorption, i.e. in the present embodiment the separation of molecules of O2 and CO2, takes place by means of the sorbent material, the remaining N2-enriched volume flow is removed as a product by means of the switching of valves provided for this purpose, for example from the first column 123 or the second column.

[0076] 124 through a line to the external consumer. As an alternative to the line to the external consumer, a product reservoir 122 can be provided into which the product is introduced. In this case, it must be ensured that unwanted backflow along the working section is prevented, which can be achieved, for example, by alternating the valves or check valves. According to the invention, N2 is separated and stored as a light component or as a product or made available to the external consumer. The singly reduced raw gas thus produced, which has an increased molar concentration of O2, CO2, H2 and possibly other gases due to the separation of N2 and is a heavy component, is not released into the ambient air as a waste product, but is further processed.

[0077] In the embodiment presented here, the simply reduced raw gas is passed on to the second adsorption module 13. Between the first adsorption module 12 and the second adsorption module 13, an additional compressor or intermediate compressor can optionally be installed.

[0078] 125, which will enable greater flexibility in process technology.

[0079] The second adsorption module 13 includes a PSA unit 131 and a product storage tank 132, which, in the exemplary embodiment presented here, is intended for storing O2. According to the invention, the PSA unit 131 and the second adsorption module 13 are designed so that they can operate independently and autonomously from other modules, in particular from the compressed air treatment module 11, the first adsorption module 12, and other adsorption modules, i.e., they can carry out the adsorption process. The PSA unit includes a first column 133 and a second column 134, which can be controlled and operated separately from one another, with lines, valves, sensors, and other components being provided accordingly.

[0080] The operation of the second adsorption module 13 is designed for continuous operation, so that the first column 133 undergoes an adsorption phase, while the second column 134 simultaneously undergoes a desorption or regeneration phase. When the adsorption phase has reached saturation, here, for example, with CO2 and / or H2, in the first column 133 or in the second column 134, which can be determined by measurement using appropriate sensors, such as a gas measuring device, the first column 133 is transferred from the adsorption phase to the desorption phase, and the second column 134 is transferred from the desorption phase to the adsorption phase by means of a control system.

[0081] Both columns 133 and 134 are filled with a sorbent material or with a formulation composed of several types of sorbent material. According to the invention, the sorbent material is flowed through or wetted with dried raw gas from bottom to top. While adsorption—in this embodiment, the separation of molecules of CO2, H2, and any residues of N2—takes place by means of the sorbent material, the remaining, O2-enriched, volume flow is passed on as a product through a line to the external consumer by switching valves provided for this purpose, for example, from the first column 133 or the second column 134.

[0082] As an alternative to the line to the external consumer, a product storage 132 can be provided into which the product is introduced.

[0083] It must be ensured that unwanted backflow along the working section is prevented, which can be achieved, for example, by alternating the valves or check valves.

[0084] According to the invention, N2 is separated and stored as a light component or as a product, or made available to the external consumer. The resulting doubly reduced raw gas, which has an increased molar concentration of CO2, H2, and possibly other gases due to the separation of O2 from the singly reduced raw gas, and is a heavy component, is not released into the ambient air as a waste product but is further processed.

[0085] In the exemplary embodiment presented here, the singly reduced raw gas is passed on to a third adsorption module 16. The third adsorption module 16 shown here is an alternative embodiment of the third adsorption module 14. The third adsorption module 16 includes a PSA unit 161 and a product storage 164, which in the exemplary embodiment presented here is intended for the storage of CO2. Optionally, the third adsorption module includes a high-pressure compressor including bundle 165. The PSA unit 161 and the third adsorption module 16 are designed according to the invention such that they can operate independently and autonomously from other modules, in particular from the compressed air treatment module 11, the first adsorption module 12 and the second adsorption module 13 and, if applicable, other adsorption modules, i.e., can carry out the adsorption process.

[0086] The PSA unit includes a first column 162 and a second column 163, which can be controlled and operated separately, with lines, valves, sensors, and other components being provided accordingly. The third adsorption module 16 is designed for continuous operation, so that the first column 162 undergoes an adsorption phase, while at the same time the second column 163 undergoes a desorption or regeneration phase. When the adsorption phase has reached saturation, here for example with CO2, in the first column 162 or in the second column 163, which can be determined by measurement using appropriate sensors, such as a gas measuring device, the first column 162 is transferred from the adsorption phase to the desorption phase and the second column 163 is transferred from the desorption phase to the adsorption phase by means of a control system.

[0087] Both columns 162 and 163 are filled with a sorbent material or with a formulation composed of several types of sorbent material. According to the invention, the sorbent material is flowed through or wetted from bottom to top with dried raw gas. Since in the exemplary embodiment presented here, the inflowing gas is a twice-reduced raw gas, which has already been reduced of N2 and O2, an increased molar fraction of CO2 is to be expected in the twice-reduced raw gas. In particular, the sorbent material can be selected and used such that any residues of N2 or O2 remaining in the twice-reduced raw gas behave like heavy components. The recovered CO2 can be forwarded as a product to an external consumer or stored in the product storage unit 164, or the product can also be compressed, for example, to 150 bar using a compressor in the optional bundle 165.

[0088] In an alternative embodiment, equivalent to the secondary stage 142, a sorbent material can be used in the PSA unit 161 in which CO2 behaves as a heavy component, i.e., is adsorbed in the sorbent material, whereby the light component, for example, H2, can be separated and forwarded as a product to a product storage 15. A gas separation device 10 designed according to the device system according to the invention allows the recovery of both H2 and N2, as well as O2 and CO2 as products.

[0089] In the present embodiment, a purity adjustment can be provided, particularly in the adsorption modules. In the first adsorption module 12, the purity of the N2 recovery can be adjustable from 2.0 to 6.0. Downstream selectivity techniques can be used for this purpose. In the second adsorption module 13, the purity of the O2 recovery can be adjustable from 2.0 to 5.0. Downstream selectivity techniques can be used for this purpose. In the third adsorption module, the purity of the CO2 recovery can be adjustable from 2.0 to 5.0. Downstream selectivity techniques can be used for this purpose. In particular, electrochemical catalysts, hollow-fiber membrane technology, and the like can be provided as downstream selectivity techniques.

[0090] Furthermore, embodiments are conceivable in which a vacuum pump 166 is provided in the third adsorption module 16, so that the process in the desorption phase can be positively influenced.

[0091] Further embodiments are conceivable that can accelerate the recovery of CO2. For example, the secondary stage can be configured to perform a variothermal process, TSA (temperature swing adsorption) and / or TPSA (temperature pressure swing adsorption), which can improve CO2 recovery.

[0092] In addition, integrated heating elements (not shown) can be provided at positions 126 and 135 to control the temperature of the sorbent material. The heat used by the heating elements can be obtained from various sources. For example, the use of waste heat from the compressors via heat exchangers or an electric reheater is conceivable.

[0093] List of reference symbols

[0094] Gas separation device

[0095] Compressed air treatment module

[0096] (first) adsorption module

[0097] (second) adsorption module

[0098] (third) adsorption module

[0099] Product storage

[0100] (third) adsorption module, second embodiment - 110 subject to change 1 filter device 2 compressor 3 dryer unit 4 air reservoir 4a air reservoir 5 water separator 6 line 7 line 8 residual dehumidification unit 9-120 subject to change 1 PSA unit 2 product reservoir 3 first column 4 second column 5 intermediate compressor 6 heating element positions 7-130 subject to change 1 PSA unit 2 product reservoir 3 first column 4 second column 5 heating element positions 6-140 subject to change 41 primary stage 42 secondary stage 143 residual dehumidification unit 144 product reservoir 145 bundle 146 line 147 high pressure compressor 148 PSA unit 149 first column 149a heating element position 150-160 subject to change 161 PSA unit 162 first column 163 Second column 164 Product reservoir 165 High-pressure compressor with bundle 166 Vacuum pump 167-1409 subject to change 1410 Second column 1410a Heating element position 1411 Compressed air line 1412 subject to change 1413 Vacuum pump 1414 First column 1415 Second column

Claims

Patent claims 1. A modular gas separation process for obtaining products from ambient air by means of modules of a modular gas separation device system, comprising: Sucking in a raw gas from the ambient air and separating O2 as the first product, N2 as the second product and CO2 as the third product from the raw gas, wherein the separation of the products takes place by one or more adsorption processes in order to make the first product, the second product and / or the third product available for further use, wherein the process can be adapted so that the products can be made available in a desired purity, in a desired quantity and / or in a desired composition, and the adsorption processes include pressure swing adsorption processes.

2. A gas separation process according to claim 1, wherein the adsorption processes further include temperature swing adsorption and temperature pressure swing adsorption.

3. Gas separation process according to one of claims 1 or 2, wherein treated raw gas is made available as a product for further use.

4. A gas separation process according to any one of claims 1 to 3, wherein separating the products from the raw gas comprises producing a reduced raw gas by separating O2 and N2 from the raw gas and subsequently separating CO2 from the reduced raw gas.

5. Gas separation process according to claim 4, wherein the separation of O2 and N2 from the raw gas occurs simultaneously.

6. Gas separation process according to one of claims 1 to 5, wherein further products comprising H2 or Ar are obtained.

7. Module set for a gas separation device (10) for implementing the gas separation process according to claims 1 to 6, comprising a compressed air treatment module (11), and an adsorption module set comprising a first adsorption module (12) for separating N2, a second adsorption module (13) for separating O2 and a third adsorption module (14, 16) for separating CO2.

8. A modular gas separation system for carrying out the gas separation process according to any one of claims 1 to 6, wherein the gas separation system comprises: Module set according to claim 7, wherein the compressed air treatment module (11) comprises a filter device (111), a compressor (112), a dryer unit (113), a compressed air reservoir (114), and each adsorption module (12, 13, 14, 16) of the adsorption module set includes an adsorption device (121, 131, 141, 142, 161), a gas line device, a connection device and control electronics.

9. Modular gas separation system according to claim 8, wherein each adsorption module (12, 13, 14, 16) of the adsorption module set is intended to further process a reduced raw gas from another adsorption module (12, 13, 14, 16) arranged in series, wherein the reduced raw gas is produced by separating at least one of O2, N2 or CO2 from the raw gas.

10. A modular gas separation system according to claim 8, wherein each module has an outer casing and / or an inner structure.

11. The modular gas separation system of claim 8, wherein the gas separation system further comprises one or more separation modules configured to recover further products comprising H2 or argon.

12. Modular gas separation device system according to claim 8, wherein each adsorption device (121, 131, 141, 142, 161) comprises two columns (123, 124, 133, 134, 162, 163) which are designed to carry out one of the adsorption processes in parallel to one another in order to produce a continuous product flow.

13. Modular gas separation system according to claim 8, wherein at least one adsorption device (121,131,141,142,161) is arranged to adjust the degree of purity.

14. Device module set for the extraction of products from ambient air, comprising a compressed air treatment module (11) according to claim 7; and at least one of the modules of the adsorption module set according to claim 7.

15. A gas separation device for recovering products from ambient air, comprising the device module set according to claim 13.

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