Apparatus, system and method for passive capture of atmospheric carbon dioxide

Abstract

An apparatus for passive capture of atmospheric carbon dioxide is disclosed. The apparatus includes a discharge chamber having an opening and a sorbent regeneration system. The apparatus also includes a capture structure connected to the discharge chamber and having at least one collapsible support and a plurality of tiles spaced apart along the collapsible support. Each tile includes a sorbent material. The capture structure is movable between a capture configuration and a release configuration. The capture configuration includes the capture structure extending upward from the discharge chamber to expose the capture structure to an airflow and enable the sorbent material to capture atmospheric carbon dioxide. The release configuration includes the collapsed collapsible support and a plurality of tiles sufficiently enclosed inside the discharge chamber so that the sorbent regeneration system can act on the plurality of tiles to release the captured carbon dioxide from the sorbent material and produce a concentrated gas.

Description

[Technical field]

[0001] Related Applications

[0001] This application claims the benefit of U.S. Provisional Patent Application No. 62 / 752,319, entitled "Device, System, and Method for Direct Air Capture," filed on October 29, 2018, and also claims the benefit of U.S. Provisional Patent Application No. 62 / 828,367, entitled "Device, System, and Method for Passive Air Capture of CO2," filed on April 2, 2019, the entire disclosures of both of which are incorporated herein by reference.

[0002]

[0002] Embodiments of the present specification relate generally to the passive capture of atmospheric carbon dioxide. [Background technology]

[0003]

[0003] The need for technology to remove carbon dioxide from ambient air has been well documented. In addition to conservation, low carbon processes, and on-site capture efforts, significant amounts of carbon dioxide need to be removed from the atmosphere to avert the looming climate change crisis. However, the technology is still new, and early air capture processes require large amounts of energy to operate. Because ambient air is very dilute with carbon dioxide, atmospheric CO2 capture devices can quickly exceed the stringent energy budget for drawing and processing large amounts of air. Furthermore, conventional carbon dioxide capture systems often suffer from the disadvantages of being costly and fragile. Conventional capture devices also often have large initial capital costs along with high operating costs. Summary of the Invention [Means for solving the problem]

[0004] According to one aspect, an apparatus for passive capture of atmospheric carbon dioxide includes a discharge chamber having an opening and a sorbent regeneration system. The apparatus also includes a capture structure connected to the discharge chamber and having at least one collapsible support and a plurality of tiles connected to and spaced apart therealong. Each tile has a sorbent material, and the capture structure is movable between a capture configuration and a discharge configuration. The device also includes a lid covering the opening of the discharge chamber when the capture structure is in the discharge configuration, and a product outlet in fluid communication with the interior of the discharge chamber and configured to receive a product flow of concentrated gas. The capture configuration includes the capture structure extending upwardly from the discharge chamber to expose at least a portion of the capture structure to the air flow to enable the sorbent material of the plurality of tiles to capture atmospheric carbon dioxide. The release configuration includes at least one foldable support for the collapsed capture structure, a lid covering an opening of the release chamber, and a plurality of tiles sufficiently enclosed inside the release chamber such that a sorbent regeneration system can act on the plurality of tiles to release the captured carbon dioxide from the sorbent material and generate concentrated gas within the release chamber.

[0005]

[0005] Certain embodiments may include one or more of the following features: The sorbent material may be a humidity swing sorbent material, and the sorbent regeneration system may include an emission medium and an emission medium emitter. The emission medium may be one of liquid water and steam. The sorbent material may be a thermal swing sorbent material, and the sorbent regeneration system may include a heat source. The heat source may be an emission medium emitter configured to emit steam. The emission chamber may further include a sweep gas inlet connected to a sweep gas source and configured to introduce a sweep gas into the emission chamber to displace the concentrated gas. The sweep gas may be steam. Each tile of the plurality of tiles may be substantially planar. For each tile of the plurality of tiles, the sorbent material may include a plurality of sorbent surfaces connected to a surface of the tile at an angle greater than zero degrees. Each tile of the plurality of tiles may include holes. Each tile of the plurality of tiles may include an upper frame and a lower frame, with the sorbent material sandwiched between the upper and lower frames. The apparatus may also include an actuator connected to the capture structure, and / or a control system communicatively connected to the actuator and configured to drive the actuator to move the capture structure between the collection configuration and the release configuration. The apparatus may further include at least one sensor communicatively connected to the control system. The control system may be configured to determine at least one ambient condition based on a signal received from the at least one sensor, and autonomously drive the actuator to move the capture structure between the collection configuration and the release configuration based on the at least one ambient condition. The at least one ambient condition may include at least one of temperature, humidity, and / or wind speed. Finally, the apparatus may further include at least one baffle.

[0006] According to another aspect of the disclosure, a method for passive capture of atmospheric carbon dioxide includes preparing a passive capture device having a release chamber and a capture structure for capturing atmospheric carbon dioxide by moving the capture structure into a capture configuration with an actuator driven by a control system. The capture structure includes at least one foldable support and a plurality of tiles connected to and spaced apart therealong, each tile having a sorbent material. The capture configuration includes the capture structure extending upwardly from the release chamber. The method also includes exposing at least a portion of the capture structure to an air flow to enable the sorbent material of the plurality of tiles to capture atmospheric carbon dioxide, and actuating the actuator to lower the capture structure into the release chamber such that the at least one foldable support is collapsed and the plurality of tiles are fully inside the release chamber, thereby placing the capture structure in the release configuration. The method further includes closing the discharge chamber with a lid to enclose the plurality of tiles inside the discharge chamber, and regenerating the sorbent material of the plurality of tiles by acting on the sorbent material with a sorbent regeneration system to release the captured carbon dioxide and generate enriched gas within the discharge chamber. Finally, the method includes discharging a product stream of enriched gas through a product outlet in fluid communication with the inside of the discharge chamber by displacing the enriched gas with a sweep gas introduced into the discharge chamber.

[0007]

[0007] Particular embodiments may include one or more of the following features: The sorbent material may be a humidity swing sorbent material, and the sorbent regeneration system may include an emitting medium and an emitting medium emitter. The emitting medium may be one of liquid water and steam. The sorbent material may be a thermal swing sorbent material, and the sorbent regeneration system may include a heat source. The heat source may be an emitting medium emitter configured to emit steam. The method may also include determining at least one ambient condition at the site of the passive capture device based on a signal received from at least one sensor communicatively connected to the control system, and / or determining an optimal exposure time for the capture structure based on the at least one ambient condition. The sweep gas may be one of air, nitrogen, water vapor, and steam.

[0008] According to another aspect of the disclosure, a system for passive capture of atmospheric carbon dioxide includes at least one passive capture cluster, each passive capture cluster including at least two passive capture devices. Each passive capture device includes a discharge chamber having an opening and a sorbent regeneration system. Each device also includes a capture structure connected to the discharge chamber and including at least one collapsible support and a plurality of tiles connected to and spaced apart therealong. Each tile includes a sorbent material. The capture structure is movable between a capture configuration and a discharge configuration. Each device also includes a lid that covers the opening of the discharge chamber when the capture structure is in the discharge configuration. Each device also includes an actuator connected to the capture structure and a product outlet in fluid communication with the interior of the discharge chamber and configured to receive a product flow of enriched gas. The system further includes a control system communicatively connected to each passive capture cluster and configured to drive the actuator to move the capture structure of the at least one passive capture device between the capture configuration and the discharge configuration. The product outlets of each passive capture device in the same cluster are in fluid communication. For each passive capture device, the capture arrangement includes a capture structure extending upwardly from the discharge chamber to expose at least a portion of the capture structure to the airflow to enable the sorbent material of the plurality of tiles to capture atmospheric carbon dioxide. For each passive capture device, the discharge arrangement includes at least one foldable support for the collapsed capture structure, a lid covering an opening of the discharge chamber, and a plurality of tiles sufficiently enclosed inside the discharge chamber to enable a sorbent regeneration system to act on the plurality of tiles to release the captured carbon dioxide from the sorbent material and generate concentrated gas in the discharge chamber.

[0009]

[0009] Particular embodiments may include one or more of the following features: At least two passive collection devices in each cluster may share the same actuator; The discharge chambers of each passive collection device in the same cluster may be in fluid communication, such that concentrated gas of one collection device may be swept through the discharge chamber of an adjacent collection device; The system may further include at least one sensor communicatively connected to the control system; The control system may be configured to determine at least one ambient condition based on signals received from the at least one sensor, and to autonomously drive the at least one actuator to move the at least one capture structure between the collection configuration and the discharge configuration based on the at least one ambient condition; The at least one ambient condition may include at least one of temperature, humidity, and wind speed; The control system may be configured to operate the passive collection devices in sequence to create a continuous product flow of concentrated gas.

[0010]

[0010] The aspects and applications of the disclosure presented herein are described in the following drawings and detailed description. Unless expressly stated, it is intended that the words and phrases in this specification and claims be given their plain, ordinary, and familiar meaning to those skilled in the art. The inventors fully recognize that they can be their own lexicographers if they wish. As their own lexicographers, the inventors expressly choose to use only the plain and ordinary meaning of a term, unless otherwise expressly stated and then further expressly state a "special" definition of the term in this specification and claims and explain how the term differs from the plain and ordinary meaning. It is the intention and desire of the inventors to apply the plain, plain, and ordinary meaning of the term to the interpretation of this specification and claims, unless the intention to apply a "special" definition is so expressly stated.

[0011]

[0011] The inventors also recognize the standard teachings of English grammar. Thus, where a noun, term, or phrase is intended to be further characterized, specified, or narrowed in any way, such noun, term, or phrase will expressly include additional adjectives, descriptive terms, or other modifiers in accordance with the standard teachings of English grammar. If no such adjectives, descriptive terms, or modifiers are used, such noun, term, or phrase will be given its plain and ordinary English meaning to one of ordinary skill in the art as set forth above.

[0012]

[0012] Furthermore, the inventors are fully informed of the criteria and application of the exceptions of 35 U.S.C. 112(f). Thus, the use of the words "function", "means", or "step" in the detailed description, the description of the drawings, or the claims is not intended to somehow indicate a desire to invoke the exceptions of 35 U.S.C. 112(f) to define the invention. To the contrary, if one seeks to invoke the provisions of 35 U.S.C. 112(f) to define the invention, the claims would specifically and explicitly recite the precise phrase "means for" or "step for" and would also recite the word "function" (i.e., "means for performing the function of [insert function]") without simultaneously reciting any structure, material, or operation that supports the function in such phraseology. Thus, it is the express intent of the inventors not to invoke the provisions of 35 U.S.C. 112(f) when a claim recites "means for performing the function of . . . " or "steps for performing the function of . . . " if the claim also recites any structures, materials, or acts that support the means or steps or perform the recited function. Moreover, when the provisions of 35 U.S.C. 112(f) are invoked to define the claimed aspects, these aspects are not limited to only the specific structures, materials, or acts described in the preferred embodiment, but are further intended to include any and all structures, materials, or acts that perform the claimed functions described in alternative embodiments or aspects of the disclosure, or any and all structures, materials, or acts that are equivalent structures, materials, or acts now known or hereafter developed for performing the claimed functions.

[0013]

[0013] These and other aspects, features, and advantages will be apparent to those skilled in the art from the following detailed description and drawings, as well as the appended claims.

[0014] The present disclosure is described below in conjunction with the accompanying drawings, in which like reference numerals refer to like elements and in which: [Brief description of the drawings]

[0014] [Figure 1A]

[0015] FIG. 1 is a perspective view of an apparatus for passive capture of atmospheric carbon dioxide. [Figure 1B] FIG. 1 is a side view of an apparatus for passive capture of atmospheric carbon dioxide. [Figure 2A]

[0016] FIG. 2 is a top view of a disc-shaped collection tile. [Figure 2B]

[0017] FIG. 2 is a perspective view of a framed collection tile. [Figure 2C]

[0018] FIG. 2 is a perspective view of a collection tile with a panel. [Figure 3A]

[0019] FIG. 1 is a side view of an apparatus for passive capture of atmospheric carbon dioxide, with the capture structure in a capture configuration. [Figure 3B]

[0020] FIG. 3B is a side view of the device of FIG. 3A, with the capture structure in a releasing configuration. [Figure 4]

[0021] FIG. 1 is a schematic diagram of a system for passive capture of atmospheric carbon dioxide comprising multiple passive capture clusters. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015]

[0022] The present disclosure, its aspects, and implementations are not limited to the specific material types, components, methods, or other examples disclosed herein. Numerous additional material types, components, methods, and procedures known in the art are contemplated for use with specific implementations of the present disclosure. Thus, for example, even if a specific implementation is disclosed, such implementations and implementation components may include any components, models, types, materials, versions, quantities, etc. known in the art for such systems and implementation components consistent with the intended operation.

[0016]

[0023] The words "exemplary," "example," or various forms thereof, are used herein to mean serving as an example, instance, or illustration. Any aspect or design described herein as "exemplary" or "example" is not necessarily to be construed as preferred or advantageous over other aspects or designs. Moreover, the examples are provided for purposes of clarity and understanding only and are not meant to limit or restrict in any way the disclosed subject matter or relevant portions of the present disclosure. It should be understood that numerous additional or alternative examples of differing scope may have been presented, but have been omitted for brevity.

[0017]

[0024] While the present disclosure includes multiple embodiments in many different forms, specific embodiments are shown in the drawings and described in detail herein, it being understood that the disclosure should be considered as an illustration of the principles of the disclosed methods and systems and is not intended to limit the broad aspects of the disclosed concepts to the embodiments shown.

[0018]

[0025] The need for technology to remove carbon dioxide from ambient air has been well documented. However, the technology is still new, and early air capture processes require large amounts of energy to operate. Because CO2 in air is very dilute (400 parts per million by volume), CO2 capture devices cannot invest huge amounts of energy to draw in large amounts of air. Heating or cooling the air, drying the air, or large fluctuations in air pressure would exceed a reasonable energy balance. Furthermore, traditional capture systems often suffer from the disadvantages of being costly and fragile. Traditional capture devices often have large initial capital costs along with high operating costs. Furthermore, traditional capture devices may be suitable for certain environments but inefficient in others.

[0019]

[0026] Contemplated herein are devices, systems, and methods for passively capturing atmospheric carbon dioxide from natural airflow or wind that are durable, energy efficient, and usable with a variety of sorbent materials, including materials that are sensitive to vacuum, heat, and / or humidity swings, or combinations thereof, in a variety of conditions. In some embodiments, the devices may be organized into clusters and systems to provide continuous capture of CO2 and provide a continuous flow of CO2-enriched gas, as discussed in more detail below. In other embodiments, the devices may be installed and operated as individual units. Furthermore, in some embodiments, some of the devices, systems, and methods contemplated herein may be implemented autonomously or semi-autonomously to adjust to changing environmental conditions in order to improve effectiveness and efficiency.

[0020]

[0027] 1A and 1B are perspective and side views illustrating a non-limiting example of an apparatus 100 (hereinafter "passive capture apparatus," "capture apparatus," or simply "apparatus") for passive capture of atmospheric carbon dioxide 102. Specifically, FIG. 1A is a perspective view and FIG. 1B is a side view.

[0021]

[0028] According to various embodiments, the capture apparatus 100 comprises a capture structure 106 configured to expose the sorbent material 110 to ambient air, a discharge chamber 104 (or regeneration chamber) into which the capture structure 106 can be placed through an opening 116, a lid 114 for sealing or otherwise enclosing the capture structure 106 inside the discharge chamber 104, means for introducing heat and / or moisture (separately or together) into the discharge chamber 104 to regenerate the sorbent material 110 and release the captured CO2, and means for extracting CO2-enriched gas from within the chamber via a product outlet 118.

[0022]

[0029] In the context of this specification and the appended claims, the release chamber 104 is an enclosure in which the captured carbon dioxide is released for subsequent sequestration, purification, or application. The release chamber 104 has at least one opening, namely opening 116, through which the release chamber 104 receives the captured carbon dioxide and the material in which it is captured (e.g., the capture structure 106 and its sorbent material 110, etc.).

[0023]

[0030] The emission chamber 104 may be constructed from durable materials suitable for both the external environment in which the recovery apparatus 100 is utilized and the internal environment specific to the operation of the emission chamber 104 (e.g., the nature of the sorbent regeneration system 306, etc.).

[0024]

[0031] According to various embodiments, the release chamber 104 includes all the equipment or structure necessary to accomplish regeneration of the sorbent material used to capture carbon dioxide, which may include some or all of the following steps, including, but not limited to: introducing liquid into the chamber, draining liquid from the chamber, forcing a sweep gas into the chamber, evacuating the chamber, heating the chamber, and injecting steam or water droplets into the chamber. For example, some embodiments may include piping support structures to allow heat, gas, liquid, etc. to be introduced and removed from the release chamber 104 as needed to perform the regeneration task. Regeneration of the capture structure 106 is discussed in more detail below with respect to FIG. 3B.

[0025]

[0032] In some embodiments, the discharge chamber 104 includes an internal flow system that includes a fan or blower to create a recirculating airflow. In other embodiments, the discharge chamber 104 may include a gas recirculation system in which the flow within the chamber 104 is driven by gas injected into the chamber 104 and returns to an external recirculation system. In passive capture systems and / or clusters, discussed below with respect to FIG. 4, multiple capture devices 100 may share a single gas recirculation system or may use a shared system in conjunction with individual internal systems.

[0026]

[0033] In the context of this disclosure and the appended claims, the capture structure 106 is a structure or collection of structures against or within which atmospheric CO2 is captured. As shown, the capture structure 106 is comprised of a plurality of tiles 108 connected to and spaced apart along one or more foldable supports 112. The tiles 108 include one or more sorbent materials 110 that serve to capture carbon dioxide. The sorbent materials 110 are discussed further below. In some embodiments, the sorbent material 110 may be disposed on one or more surfaces of the tiles 108, and in other embodiments, the tiles 108 themselves may be made from the sorbent material 110. As discussed, the sorbent material 110 releases the captured CO2 when it is recycled (e.g., when it is attached to the sorbent regeneration system 306 inside the release chamber 104).

[0027]

[0034] As shown, when the capture structure 106 is "deployed," i.e., exposed to the atmosphere for capturing carbon dioxide, the tiles 108 are suspended along one or more foldable supports 112 such that air can flow between the tiles 108 from either direction. Such an arrangement is advantageous when used to capture CO2 from natural air currents and wind, which may change direction. Additionally, although the tile-based structures contemplated herein are described in the context of use with passive air flow, it should be understood that they may also be used with forced air flow.

[0028]

[0035] The non-limiting example shown in Figures 1A and 1B is an elongated cylinder and utilizes circular tiles. In some embodiments, the devices and / or tiles 108 may have a generally circular cross-section, which may be advantageous for use in passively capturing air in situations where airflow may come from any direction. In other embodiments, the devices and / or tiles 108 may have a non-circular cross-section. Various tile 108 shapes are discussed in more detail below with respect to Figures 2A, 2B, and 2C.

[0029]

[0036] As shown, the capture structure 106 may comprise an overlap of tiles 108. According to various embodiments, the overlap of the capture structure 106 ranges from a small number (5-10) of tiles to a large number (>1000). Particular embodiments utilize an overlap of 50-200 tiles.

[0030]

[0037] The tiles 108 are supported by one or more collapsible supports 112 which, when raised, allow the tiles to sag unrestrained under gravity, thereby allowing air to pass through the gaps between the tiles. In many embodiments, when the capture structure 106 is folded inside the release chamber 104, the tiles 108 rest against each other using small spacers to maintain a small gap between the tiles 108 when they are at rest within the chamber 104.

[0031]

[0038] In addition to capturing atmospheric carbon dioxide, the capture structure 106 is movable between an arrangement suitable for capturing atmospheric carbon dioxide (e.g., a capture configuration) and an arrangement that allows the captured CO2 to be released into the release chamber 104 (e.g., a release configuration). The capture and release configurations are discussed with respect to Figures 3A and 3B below.

[0032]

[0039] As mentioned above, the tiles 108 are connected to and spaced apart along one or more foldable supports 112. For example, Figures 1A and 1B show a non-limiting example with a single foldable support 112 that runs through the central axis of the tile 108. Examples of foldable supports 112 include, but are not limited to, thin ropes, strings, or chains. In one embodiment, each tile 108 may be connected to the tile above, thereby carrying the weight of all the tiles 108 below it. In another embodiment, the foldable supports 112 are continuous and designed to carry the weight of all the tiles 108, and the structure of the tiles 108 is designed to carry only its own weight. To provide a concrete example of such a support system, imagine a number of long, thin ladders formed from long strings or chains and solid rods for rungs. These ladders are thin, for example, one centimeter wide, or may be many centimeters wide. A minimum of three such ladders are evenly spaced around the edge of the tiles 108, with each tile 108 being able to be hooked onto one rung. The ladder structure supports the weight of all the tiles 108, while each individual tile 108 only needs to support its own weight. By increasing the number of ladders, the thickness of the strings including the sides of the ladder can be reduced, making it easier to fold the ladder. Advantageously, a number of ladders greater than three allows for the removal and replacement of one ladder during maintenance while the capture structure 106 is in the open / retrieval configuration.

[0033]

[0040] In another embodiment, the tiles 108 may be held by a telescoping tube or rigid rod that folds against the tiles 108 in a zigzag pattern to create a "dog bone" shape that protrudes from the lower tile 108 into the open space of the upper tile 108. In this design, successive tiles 108 may need to be fixed in different positions, shifted by a slight angle, to allow space for the length of the dog bone so as not to interfere with the dog bone of the tile 108 above.

[0034]

[0041] In yet another embodiment, the foldable support 112 may be a cone shape that surrounds a hole in the center of the tile 108. The tiles 108 rest on each other when stacked, widening their distance as the cones move slightly apart. Such a design would naturally help the tiles 108 to center naturally when stacked. If the cones are truncated and therefore open at the top, they would create an open vertical channel through the center of the folded stack of tiles 108 that can help direct airflow during regeneration of the tiles 108. Those skilled in the art will recognize that other foldable configurations exist.

[0035]

[0042] According to various embodiments, the tiles 108 of the capture device 100 are separated from one another when in the capture configuration or capture phase, and overlap one another when in the regeneration or discharge phase. Optionally, sensitive portions of the tiles 108 may be protected from contact with other tiles by cushioning structures such as pads or rims. The cushioning may be configured in a manner to direct airflow to increase capture and / or intake.

[0036]

[0043] When the stack of tiles 108 is hanging loose, it may be advantageous to limit its movement (e.g., to prevent damage, optimize sorbent exposure, etc.). One way to limit movement is to place the hanging stack between guides when it is lifted. An example is a set of vertical poles, which can also provide structural support for the lifting structure. Three such poles are already sufficient to limit the lateral movement of the tiles 108. Another embodiment may have the tiles 108 connected through a guide along a central hole, which prevents relative movement of the tiles 108. If the tiles 108 and the lid 114 are ring-shaped, a guide can also be threaded inside the tiles 108. Another option for limiting the movement of the tiles 108 is to anchor the lower tile 108 to the bottom of the release chamber 104.

[0037]

[0044] According to various embodiments, the tiles 108 may be connected to the bottom of the lid 114, which is raised along with the tiles 108 when the device 100 is opened to the retrieval configuration. In other embodiments, the lid 114 may open sideways, by sliding or hinged like a door. A lifting mechanism is then connected to a fitting on the top of the capture structure 106 to lift the tiles without the lid 114. Such a design is particularly beneficial in a cluster of retrieval devices 100 where the lifting mechanism can be shared between multiple devices 100. Optionally, the capture structure 106 may be attached to some form of support structure once fully lifted.

[0038]

[0045] According to various embodiments, the passive capture device 100 may be used with a variety of sorbent materials 110, including solid and liquid sorbents, that can be regenerated by various means. The sorbents may be made of inorganic or organic materials, or may be composite materials. The sorbents may be materials that chemically or physically bind CO2, i.e., the sorbents may be absorbents. The sorbents may also be adsorbents that bind CO2 to an internal surface, for example, an internal porous structure, or to a fiber surface. The sorbents can be regenerated with a humidity swing, a thermal swing, a vacuum swing, or a combination of these techniques. The above discussion of different sorbents is intended to illustrate options, rather than provide an exhaustive description. Other sorbent-based technologies feasible by one of ordinary skill in the art may be adapted for use with the device 100.

[0039]

[0046] In one embodiment, the passive capture device 100 may utilize a sorbent material 110 that can be regenerated by liquid washing, which carries CO2 out of the discharge chamber 104 as part of the liquid washing. The liquid may release its CO2 inside the discharge chamber 104, or the liquid may be carried outside the discharge chamber 104 where it will undergo further processing to release the CO2. For example, the passive capture device 100 may use a weak carbonate brine that is converted to bicarbonate brine by a humidity swing sorbent, which is then subjected to its own various regeneration schemes, possibly including the use of electrochemical regeneration.

[0040]

[0047] As a specific example, the sorbent material 110 may be one of several anion exchange resins that have a strong affinity for CO2 when dry and lose this affinity when wet. These are strong base exchange resins, exemplified by polystyrene with quaternary ammonium ions attached to the styrene structure. In any case, at temperatures near room temperature, changing the relative humidity on the resin from 20% to 100% changes the equilibrium partial pressure on the resin by a factor of 500 at any loading. Other embodiments may be designed around a sorbent 110 that is regenerated by heat, vacuum extraction, or regeneration by another chemical action.

[0041]

[0048] The sorbent 110 may be selectable for one sorbent or may interact with multiple sorbents that cooperate or compete with each other. The sorbent 110 may autocatalyze its own absorption. As a specific example, some embodiments may utilize sorbents whose affinity for CO2 can be controlled by moisture. The presence of moisture can increase or decrease the binding of CO2 to the sorbent. One particular class of sorbents, known as humidity swing sorbents, binds CO2 under dry conditions and releases it again when moistened. Some humidity swing sorbents, such as polystyrene with quaternary ammonium ions, react strongly to relative humidity. This means that the effect of increasing the temperature of the ambient air increases the amount of CO2 attached to the sorbent, because the associated decrease in relative humidity reduces the Gibbs free energy of sorption more than the increase in temperature increases it. However, if warming is performed at a constant relative humidity, e.g., 100% relative humidity, or in a wet state, heating the sorbent will force the CO2 out of the sorbent. Thus, humidity swing sorbents may be used with moisture alone or with a combination of moisture (e.g., liquid water, mist or other droplet form, steam, etc.), temperature, and pressure. In some embodiments, the use of such versatile sorbents may be optimized using algorithms that take into account ambient conditions and select regeneration paths based on efficiency, as discussed further below.

[0042]

[0049] Some embodiments utilizing humidity swing sorbents may utilize liquid water for regeneration, while other embodiments may use steam. Each regeneration medium has its own advantages and disadvantages. Liquid water is fast to uptake but is prone to introducing impurities such as salts into the sorbent and system, especially if the water is provided from an underground source. Steam can be advantageously used to provide heat as well as moisture. However, when operating in a low pressure system, steam may transfer excess heat that can be difficult to remove. Some embodiments may utilize both steam (called water vapor at low partial pressures) and liquid water. In embodiments without a humidity swing, or those utilizing a reverse humidity swing, liquid water may not provide any benefit over the use of steam alone.

[0043]

[0050] The heat-moisture-vacuum design used in some embodiments provides many advantages over conventional devices. In particular, it allows for the application of humidity swing-based CO2 capture devices in a variety of climates, including even those subject to high levels of humidity and / or colder weather. Contemplated devices 100 utilizing humidity swing sorbents may be particularly useful in relatively cold and wet climates. However, while the following discussion of various embodiments of contemplated capture devices 100 is conducted in the context of a heat moisture-based regeneration system, it should be understood that the structures and methods discussed herein may be adapted to other types and forms of sorbents 110 and appropriate regeneration steps may be performed in a closed or sealed release chamber 104.

[0044]

[0051] Once the capture structure 106 is completely filled with captured carbon dioxide, it is moved into the release chamber 104 where the CO2 is captured and the sorbent material 110 is regenerated in preparation for further capture. According to various embodiments, capture of the captured CO2 and regeneration of the sorbent material 110 occurs after the release chamber 104 is closed by placing a lid 114 over the opening 116. According to various embodiments, the lid 114 (and capture structure 106) may be lowered onto the opening 116 (and the capture structure into the chamber 104) by some form of actuator 120. In the context of this specification and the appended claims, actuator 120 is any device capable of affecting movement and may include, but is not limited to, a motor, a piston, a hydraulic, a screw drive, an elevator, a roller, and other devices known in the art. As an option, actuator 120 may be connected directly to capture structure 106, through the lid 114, or through some other structure. In some embodiments, the actuator 120 may also be connected to the emission chamber 104. According to various embodiments, the lid 114 is configured to mate with the emission chamber 104 to form a closed chamber. In some embodiments, the lid may form an airtight seal with the emission chamber 104.

[0045]

[0052] As shown, the passive capture system 100 also includes a product outlet 118. The product outlet 118 allows for fluid communication between the inside of the discharge chamber 104 and some structure outside the discharge chamber 104 (e.g., a storage system, an upgrade system, another discharge chamber 104, etc.) to allow for the collection of a product stream that is rich in CO2 (e.g., a higher ratio of CO2 to other substances than is present in ambient air). In some embodiments, the product outlet 118 may be configured for a gaseous product stream, and in other embodiments, the product outlet 118 may be configured to discharge a liquid product stream (e.g., CO2 captured in brine, etc.).

[0046]

[0053] It is important to note that while the term tile 108 is derived from one possible design in which the tile 108 is flat, in the context of this disclosure, the term tile 108 is intended to accommodate a much broader range of shapes. In some embodiments, the tile 108 is made entirely from a sorbent material, while in other embodiments, the tile 108 is made from a structural material that holds the sorbent material 110 in place. For example, in some embodiments, a liquid sorbent (e.g., an ionic liquid) may be used by wetting the structural surface of the tile 108. As a specific example, a foam material may be used in conjunction with a liquid sorbent.

[0047]

[0054] In some embodiments, the tiles 108 may have a circular cross-section (along the central axis of the overlap). In other embodiments, other shapes may be utilized, including but not limited to shapes resembling circles (e.g., higher order polygons), triangles, rectangles, squares, hexagons, stars, rings, etc. Circular cross-sections may be suitable for use in environments where wind direction is unpredictable, while in other embodiments, more elliptical tiles 108 may be utilized in conditions with frequent wind directions.

[0048]

[0055] 2A, 2B, and 2C show diagrams of non-limiting examples of various tile 108 shapes. FIG 2A shows a top view of a non-limiting example of a disk-shaped tile 200 having humidity swing sorbent material 220. As shown, disk-shaped tile 200 includes a central hole 202 through which foldable support 112 may pass and connect to the respective tile 108 and / or through which air may flow.

[0049]

[0056] In some embodiments, tiles 108 may hang down from a structure such as lid 114 while exposed to wind, and may rest on each other when lowered into emission chamber 104. According to various embodiments, tiles 108 may include reinforcing pads, rims, or lips designed to carry the weight of the tile 108 above when the overlap is in a collapsed configuration. These pads may also extend vertically wider than the more fragile portions of tiles 108 (e.g., sorbent, etc.), thereby limiting physical contact between tiles 108 to locations designed to carry this weight. In some embodiments, tiles 108 (whether round or with corners) may have sorbent / resin hanging down from them, which may be in addition to the sorbent throughout the tile 108.

[0050]

[0057] The structure of the tiles 108 and the mechanism for suspending the tiles 108 may be adjusted based on local terrain and weather conditions. For example, in areas with high winds, the tiles 108 may be substantially more sturdy or may be completely separate from the chamber 104 to ensure best support. In some embodiments, there may be a support structure that folds up or is hidden during high winds to pull the sometimes fragile tiles 108 into a shelter. The numerous options for support structures for raising and lowering the tiles 108 simply reflect the various needs that may exist for an apparatus that can be placed almost anywhere in the world.

[0051]

[0058] In some embodiments, the tiles 108 are essentially flat except for a rim or pad used in the overlap. In other embodiments, the tiles 108 may be non-planar, such as bowl-shaped or helmet-shaped. In yet other embodiments, the tiles 108 may comprise a framework that surrounds or otherwise protects the sorbent material 110.

[0052]

[0059] 2B shows a perspective view of a non-limiting example of a framed tile 204 comprising an upper frame 206, a lower frame 208, and a central hole 202. According to various embodiments, the two frames may be connected together to enclose or sandwich the sorbent material 110 or a material configured to hold the sorbent material 110 (e.g., a foam material for holding a liquid sorbent, etc.) and hold it in place while still allowing it to be exposed to airflow. Such tiles 108 may be beneficial for use with sorbent materials 110 that are otherwise too brittle to be used as a material from which to make tiles, materials 110 that have non-negligible dimensional variations (e.g., expansion, contraction, etc.) when cycled between wet and dry conditions, or sorbent materials that must be contained in a material that would have limited exposure to air if placed on a solid tile such as the disc-shaped tile 200 of FIG. 2A.

[0053]

[0060] 2C is a perspective view of a non-limiting example of a paneled tile 210 including multiple sorbent surfaces 212 made from a thermal swing sorbent material 218. In some embodiments, the tiles 108 may be highly structured to facilitate contact of their surfaces with gas. The tiles 108 may include channels or passages that create a gas flow path from the top to the bottom of the tiles 108 to facilitate gas flow in intimate contact with the sorbent material 110 of the tiles 108.

[0054]

[0061] In some embodiments, the tile 108 may be one large sorbent structure. In other embodiments, including the non-limiting example shown in Figure 2C, the sorbent material 110 may be sectioned into slices or surfaces 212 that are individually attached to a surface 214 of a paneled tile 210. One such tile may be a hexagon, such as the tile shown in Figure 2C, or may be a triangular tiling of the surface of the tile 108.

[0055]

[0062] To maximize air mixing, the surfaces of the tiles 108 may be uneven and rough, and adjacent tiles 108 may have different shapes in close proximity. For example, if the tiles 108 are made up of multiple different tiles, the surfaces that overlap vertically need not necessarily be identical or oriented in the same way. In some embodiments, the sorbent surface 212 may be inclined relative to the surface 214 of the tile 210, forming an angle 216.

[0056]

[0063] In some embodiments, the tiles 108 may be fitted with triangular (or some other raised shape) raised sorbents and baffles to increase exposure and create turbulence to increase capture.

[0057]

[0064] 3A and 3B are side views of non-limiting examples of a capture device 100 having a capture structure 106 in a capture configuration 300 and a release configuration 312, respectively. A portion of the release chamber 104 has been removed to reveal the interior of the release chamber 104, including a sorbent regeneration system 306.

[0058]

[0065] 3A illustrates a capture structure 106 in a collection configuration 300 comprising a capture structure 106 extending upward from a discharge chamber 104 with at least a portion 302 of the capture structure 106 exposed to an air flow 304. According to various embodiments, the ambient air contacts the sorbent material 110 of the capture structure 106 by natural air movement (e.g., wind), by induced flow (e.g., thermally induced flow or flow induced by a pressure drop resulting from forcing natural flow through a flow path), by flow induced by a blower, fan, or other mechanical system, or by a combination of these and other methods known in the art.

[0059]

[0066] As shown, the capture apparatus 100 includes a sorbent regeneration system 306. In the context of this specification and the appended claims, the sorbent regeneration system 306 is a system that generates, provides, conducts, or facilitates the media or energy required to release captured CO2 and regenerate the sorbent material 110 in preparation for further CO2 capture. In some embodiments, the sorbent regeneration system 306 may include an emission media emitter 308 that emits an emission media (e.g., mist, liquid water, steam, other chemicals, etc.) appropriate for the sorbent material 110 being used into the emission chamber 104. In other embodiments, the sorbent regeneration system 306 may include a heat source 310 (e.g., for thermal swing sorbent materials). In still other embodiments, including the non-limiting example shown in FIG. 3A, the sorbent regeneration system 306 may include both the emission media emitter 308 (or emitters) and one or more heat sources 310. As a specific example, some embodiments may utilize an emission media emitter 308 configured to emit steam into the emission chamber 104, thereby providing both moisture and heat to facilitate the use of moisture-swinging and / or heat-swinging sorbent materials. In yet other embodiments, the heat source 310 radiates heat provided by steam, which may optionally be emitted into the chamber (e.g., may be configured to provide heat without moisture for some sorbent materials).

[0060]

[0067] 3B illustrates the capture apparatus 100 of FIG. 3A where the capture structure 106 is a release configuration 312. In the context of this disclosure and the appended claims, the release configuration 312 comprises the capture structure 106 (e.g., a plurality of tiles 108 and one or more collapsible supports 112) enclosed within the release chamber 104 for the regeneration of the sorbent material 110 and the capture of the captured carbon dioxide 314. As discussed above, the release configuration 312 may further comprise a lid 114 connected, mated, or sealed to the release chamber 104 such that the chamber 104 is sufficiently closed to accomplish regeneration and capture.

[0061]

[0068] When the capture structure 106, or a portion of the capture structure 106, becomes saturated with CO2 and is moved into the release chamber 104, the sorbent material 110 is regenerated and releases the captured CO2 314 into the release chamber 104. As previously discussed, this regeneration and release is accomplished by the sorbent regeneration system 140.

[0062]

[0069] The following discussion of the regeneration or release phase of the passive capture device 100 is done in the context of heat and moisture sensitive sorbent materials. However, it should be apparent to one skilled in the art that the passive capture device 100, its capture structure 106, and release chamber 104 may be adapted for use with any of the sorbents and their associated regeneration processes described above. The procedures in the context of heat and moisture are illustrative of other embodiments using other sorbents, since some form of introduction of heat and / or liquid is a common element in the regeneration of many different sorbents. Such discussion should not be construed as limiting.

[0063]

[0070] The regeneration system 306 applies a combination of heat, pressure fluctuations, and / or chemicals (including water) to the sorbent material 110 to return it to its initial state and release CO. In different embodiments, the CO enriched intermediate product may be subjected to different pressures and temperatures, and CO may be only a portion of the intermediate product stream.

[0064]

[0071] According to various embodiments, the sealed emanating chamber 104 may be filled with air, nitrogen, or other sweep gas 322, which may be provided from a sweep gas source 320 via a sweep gas inlet 318. The chamber 104 may be evacuated or partially evacuated to remove most background gases. In some embodiments, the emanating chamber 104 may be evacuated or otherwise prepared prior to regeneration. The sorbent material 110 captures a large amount of CO2 in the open air and releases it inside the emanating chamber 104 after exposure to moisture and / or heat or after contacting a chemical. As a result, CO2 loss can be minimized during the emanating step or other preparation steps, since the vacuum step or other preparation steps are performed before heat and moisture are introduced.

[0065]

[0072] As previously discussed, according to various embodiments, the sorbent 110 releases the captured CO2 in response to the addition of heat and / or moisture. Heat can be obtained from a variety of sources. In many applications, the heat source temperature may be well below 100° C., so the heat quality may be very low. Heat sources may include, but are not limited to, geothermal heat, waste geothermal heat left over after the hotter geothermal heat has been used for some other application, residual heat from power plants and other energy consumers, solar heat, and heat recovered from cooling solar panels. Solar heat may be added, for example, by including a chamber designed to capture solar heat around the release chamber 104.

[0066]

[0073] In some embodiments, waste heat generated by a CO2 compression system in conjunction with the output of the passive capture apparatus 100 (e.g., product stream 326) may be reused to heat the discharge chamber 104. In other embodiments, heat may be introduced by delivering moisture as water vapor that can be condensed in the chamber 104. In other embodiments, heat may be delivered via a heat exchanger. In some embodiments, the source of heat and moisture may be derived from equipment outside the chamber 104. In other embodiments, the heat source may be integrated into the discharge chamber 104. The chamber may have an exit point for the condensed water along with an exit point for the product stream 326 of the enriched gas 324. The CO2 enriched gas 324 is removed from the chamber as product stream 326 for further processing.

[0067]

[0074] In the context of this specification, the release medium 316 is a material or substance that stimulates the release of CO2 from the sorbent material 110. In the case of the humidity swing sorbent material 220, the release medium 316 may be liquid water or steam. In other embodiments, the release medium 316 may be any other solution or substance that is compatible with the particular sorbent material 110. Furthermore, in the context of this specification and the appended claims, the release medium emitter 210 is a device configured to promote the interaction of the release medium 316 with the sorbent material 110 saturated with CO2. Exemplary release medium emitters 210 include, but are not limited to, mist generators, nozzles, fog generators, liquid jets, a reservoir of release medium through which the sorbent passes, steam nozzles, and the like.

[0068]

[0075] The use of steam as the release medium 316 offers certain advantages over other release media 316 because it can be used with some thermal swing sorbent materials in addition to humidity swing sorbents. The steam transfers heat to the sorbent, further inhibiting water extraction.

[0069]

[0076] In embodiments in which the release medium 316 takes the form of a liquid, during or after application by the emitter 210 (e.g., when the steam cools and condenses into liquid water), the sorbent regeneration system 306 may further include one or more liquid extractors 313, which are devices and / or systems configured to collect and remove the liquid release medium 316 from the chamber 104 after it has stimulated the release of CO2, for disposal, immediate reuse, conditioning for reuse (e.g., removing impurities), or as a CO2 storage medium. Additionally, embodiments utilizing water vapor as the release medium 316 may also include one or more liquid extractors 313 to remove liquid water produced by condensation inside the chamber.

[0070]

[0077] The liquid extractor 313 includes an outlet at the bottom of the chamber 104 that may be connected via a pump to a release medium reservoir. The recovered liquid water may be pumped back to the reservoir for repeated use to reduce the overall amount of water required to operate the recovery device 100 and allow the recovery device 100 to be used in environments where water availability is low.

[0071]

[0078] In some embodiments, the product stream 326 may be generated by displacing the enriched gas 324 with a sweep gas 322 introduced inside the discharge chamber 104. In some embodiments, the sweep gas 322 is atmospheric air, while in other embodiments, the sweep gas 322 is another gas that is readily available.

[0072]

[0079] Some embodiments may utilize steam as the sweep gas 322, which can provide certain advantages. The use of steam provides a means for temperature manipulation within the regeneration chamber. The temperature can be increased by injecting steam, and the chamber and its contents can be intentionally cooled by exhausting the steam. Additionally, the use of a water-saturated sweep gas, such as steam (referred to as water vapor at low partial pressures), can advantageously keep the humidity swing sorbent from releasing water, thereby increasing the overall efficiency of the apparatus 100.

[0073]

[0080] As noted above, in some embodiments, the captured CO2 314 can be released from the sorbent 110 into an aqueous solution with sufficient alkalinity to store CO2. An example is sodium or potassium carbonate, which can have abundant levels of bicarbonate in equilibrium with a few percent of CO2 throughout the solution. In effect, the solution that is brought into contact with the material 110 promotes a humidity swing, which then traps the CO2.

[0074]

[0081] As a specific example, in embodiments utilizing an anion exchange resin, quaternary ammonium ions form a strong base resin in which the cations are immobilized in a polymer matrix while the anions, i.e., hydroxide (OH-), are free to move. When the dry resin picks up carbon dioxide, the hydroxide ions become bicarbonate (OH- + CO2 → HCO 3- Once full, the resin is enclosed in an emission chamber 104 where it is wetted. The wetted resin releases CO2, which separates into carbonate (2HCO 3- →CO 3-- +CO2+H2O). Ion hydration promotes the affinity of CO2 (CO 3-- +H2O→HCO 3- +OH - ), while the water content promotes equilibrium. The CO2-laden liquid may then be removed from the chamber 104 for processing elsewhere or for continued storage.

[0075]

[0082] In some embodiments, air may be removed from the chamber 104 prior to releasing the CO2 to raise a small gas flow containing CO2. Options may include using a vacuum along with heat and / or moisture. Additionally, moisture may be introduced as H2O or other substances, or as H2O with additives.

[0076]

[0083] In some embodiments, the release chamber 104 may be at least partially evacuated during the regeneration or release phase. In these embodiments, it is important that the seal between the lid 114 and the release chamber 104 minimizes gas flow inside. To this end, a gasket 315 may be present between the lid 114 and the top of the chamber 104. Attaching the gasket 315 to the bottom of the lid 114 may help protect the lid from dust accumulation. In some embodiments, the seal is further improved by providing a rim around the edge of the lid 114, which creates a narrow recess around the edge of the lid 114 when the lid 114 is closed. This recess can be filled with water, which effectively prevents air from entering the closed chamber 104 and is easily detected. The remaining flow into the chamber 104 is greatly reduced, since the resistance to flow is much higher for liquid than for air.

[0077]

[0084] During regeneration of the sorbent 110, the CO2 partial pressure is raised above ambient levels. In embodiments where the release chamber 104 is substantially evacuated, the water vapor present may then act as the sweep gas 322. This means that in order for gas to pass from one chamber 104 to another, the temperature (and therefore the water vapor pressure) must be adjusted from the flow path where the sweep gas 322 enters to the flow path where the sweep gas exits. At a minimum, the temperature variation must compensate for the pressure rise of the CO2 that occurs during the regeneration process.

[0078]

[0085] In some embodiments, such as those in which the release chamber 104 has the shape of a vertically aligned drum, the mixed flow pattern routes gas axially along the central opening of the capture structure (e.g., holes 202 in the disk-shaped tiles 200) and back along an annular region along the cylindrical wall of the chamber 104, creating a radial air flow from the central flow to the outer annular flow at all horizontal levels of the chamber 104. In such embodiments, the vertical sections of flow experience little flow resistance, while the radial link is the main flow impedance. As a result, each level experiences the same pressure drop and therefore experiences similar flow rates. The impedance to flow can be maintained by forming a wall with small openings around the inner flow cylinder and the outer flow path through the annulus. Other options include flow moving axially through the main portion of the chamber 104 and returning through an annular cap between the sorbent material stack and the wall of the chamber 104.

[0079]

[0086] In some embodiments, the released CO2 may be collected and made into a gas stream that flows through the release chamber 104. The gas may be recirculated over the sorbent by mechanical means. This gas may be primarily water vapor and carbon dioxide, or may contain most components of air, may include pure nitrogen, or may be any other gas selected as the sweep gas 322. Additionally, airflow through the chamber may be controlled by a pump, fan, or blower that directs heated air over the sorbent and another fan that extracts CO2-rich air from the chamber.

[0080]

[0087] In some embodiments, a mechanically driven heated gas stream flows over the sorbent and uses moisture and heat to cause the release of CO2 from the sorbent at partial pressures significantly exceeding the pressure of the ambient air. High partial pressures are most desirable. According to various embodiments, pressures achieved in similar chambers range from 0.1 kPa to 8 kPa.

[0081]

[0088] After the CO2 is released from the sorbent material 110 of the capture structure 106 inside the chamber 104, the CO2 is mixed to produce enriched gas 324. According to various embodiments, the enriched gas 324 is then removed from the chamber 104 as product stream 326 through product outlet 118. In some embodiments, product outlet 118 may be a valve and in other embodiments may comprise a pump. The product outlet 118 is in fluid communication with the inside of the release chamber 104.

[0082]

[0089] As shown, the capture apparatus 100 further comprises a control system 328. According to various embodiments, the control system 328 is responsible for the cyclic operation of the capture apparatus 100. In the context of this specification and the appended claims, the control system 328 is a device capable of executing a set of predetermined instructions to cause the capture apparatus 100 to cyclically operate to capture CO2 from the atmosphere and release it into the release chamber 104. Examples include, but are not limited to, embedded systems, conventional computer systems, mobile devices, and the like. The control system 328 is communicatively connected to various components that provide information (e.g., sensors, etc.) or perform actions (e.g., actuators 120, sorbent regeneration system 306, etc.). In some embodiments, the control system 328 may be responsible for additional functions. In some embodiments, the control system 328 may provide automation of the capture apparatus 100, allowing the capture apparatus 100 to operate unattended.

[0083]

[0090] The capture device 100 may further include one or more sensors 330 (e.g., CO2, humidity, temperature, airflow, light, etc.) connected to a processor configured with algorithms for efficient operation of the device 100. The passive capture device 100 may further include actuators 120 or other means for performing mechanical operations for raising and lowering the capture structure 106. The passive capture device 100 may also include communication equipment for remote monitoring and operation. In some embodiments, the passive capture device 100 may be configured for autonomous operation as needed to adapt to ambient conditions 332. Power may be provided directly via a battery or from renewable sources such as solar, wind, or thermoelectric.

[0084]

[0091] According to various embodiments, one or more measurements may be made using the sensor 330 and the signal 334 is observed by the control system 328. These measurements may include, but are not limited to, wind speed and other weather data, humidity inside and outside the chamber, time, CO2 removal gas percentage, internal temperature of the chamber 104, flow rate (to detect obstructions), component malfunctions and / or instability during operation, outside and inside air temperatures, etc. Using this information, the control system 328 may be configured to perform one or more actions depending on the detected ambient or internal conditions. These actions may include, but are not limited to, commands to lower the tiles 108 due to high winds or excess moisture, timed commands to raise and lower the tiles 108 to vary exposure time, start, stop, increase or reduce flow rate, extend or shorten time in the release chamber 104 depending on CO2 loading.

[0085]

[0092] In some embodiments, the passive capture device 100 may be configured to adjust the delivery of heat and moisture to suit particular circumstances or ambient conditions 332, such as temperature 336, humidity 338, and / or wind speed 340. For example, during hot, dry days in the desert, the performance of the device 100 may be optimized without the use of additional heat, while at night when the relative humidity increases, it may be advantageous to heat the gases recirculating in the release chamber 104. In some embodiments, this adjustment during capture and / or release may be enhanced by applying artificial intelligence to the control system.

[0086]

[0093] Some embodiments of the passive capture system 100 may utilize algorithms developed to generate the best reaction from the sorbent 110. These algorithms are designed to efficiently combine the use of heat and moisture. These algorithms optimize the balance between performance and operating costs, whereby water and heat are introduced to optimize CO2 delivery at an optimal rate and optimal partial pressure. According to various embodiments, the optimization may take into account the ambient temperature, the loading condition of the sorbent 110, weather conditions, heat and water costs, and other relevant parameters. In some embodiments, the temperature of the CO2 release in the chamber 104 may be targeted to be higher than the ambient temperature. The optimal temperature varies depending on the environmental conditions and the heat resistance of the material, and may also be influenced by the cost of available heat. In certain embodiments, the range is from ambient to 150°C, but may preferably operate in the range of 45 to 50°C, depending on the sorbent. For many sorbents, this temperature range is still sufficient, and the cost of heat is relatively small. When the sorbent 110 is saturated with water and heated, it will release CO 2 into the enclosed volume of the release chamber 104 .

[0087]

[0094] According to various embodiments, the control system 328 may further comprise or be commanded by an artificial intelligence system 317 (AIS) that monitors and iteratively adapts the performance of the equipment 100 to maximize production and learn different optimizations depending on weather conditions and the physical state of the equipment 100. The AIS 317 improves efficiency, reduces energy costs, and reduces maintenance. For example, the AIS 317 connected to the control system 328 of the equipment 100 may "learn" that certain alerts are not critical and adjust the behavior of the particular alert and provide notifications accordingly. Reducing the number of alerts requiring a response contributes greatly to reducing operating costs.

[0088]

[0095] The control system 328 may utilize software configured to control one or more operations or characteristics including, but not limited to, the rate of addition of moisture in the form of liquid / mist / steam, internal temperature, flow rate of sweep gas, pumping speed for extracting product gas, timing of exposure to air, time in the discharge chamber 104, etc. The software may be configured to optimize various characteristics such as yield, water consumption, and / or energy consumption.

[0089]

[0096] The automation systems may further include, but are not limited to, wind / weather measurement and response, CO2 capture monitoring, automatically timed movement of the capture structure 106 and / or support structure 108, water and air control systems, temperature measurement and control, internal flow measurement, timing control to accommodate the functioning of other systems, etc.

[0090]

[0097] In some embodiments, the passive capture device 100 may further comprise a series of baffles to modify the airflow and / or protect various sides of the device 100. In the context of this specification and the appended claims, a baffle is a structure having at least one surface that can at least partially block, redirect, or focus the airflow. Some baffles may also at least partially block light and may be used to protect sensitive sorbent materials. Examples include, but are not limited to, sails, walls, fins, wings, etc. Some baffles may be rigid, others flexible, or may comprise flexible surfaces attached to a rigid frame. Some embodiments may use baffles to introduce or enhance turbulence in the local airflow to increase exposure to the sorbent material.

[0091]

[0098] According to various embodiments, baffles may be utilized in various contexts. In some embodiments, one or more baffles may be used external to the capture device 100. See, for example, baffle 408 shown in FIG. 4, discussed further below. In other embodiments, one or more baffles may be implemented within or as part of the capture device 100. For example, in one embodiment, the tile 108 may have one or more baffles above and around the central hole 202 to promote and / or control airflow. In another embodiment, a baffle may be used on the tile 108 to protect the sorbent material 110 from exposure to harmful UV light. Additionally, a baffle may be used on the tile 108 to increase air turbulence and direct airflow toward the sorbent 110 when the capture structure 106 is in the collection configuration 300.

[0092]

[0099] In some embodiments, the baffles may be articulated and further mechanized and programmably movable to respond to different ambient conditions. In some embodiments, baffles may be present at the bottom and along the sides within the chamber 104 to increase airflow and moisture distribution. However, in other embodiments, the passive collection device 100 may not utilize baffles at all.

[0093]

[0100] A passive capture device 100 may be standalone or may be the backbone of a larger air capture system, such as a passive capture cluster 402 comprised of two or more integrated capture devices 100, or a passive capture system 400 including at least one cluster 402. A complete passive capture system 400 may be built around two capture devices 100, or may comprise a complex interconnected network of thousands of capture devices 100. In one embodiment, an interconnected system of 5-20 capture devices 100 comprises a passive capture cluster 402, while in other embodiments, the cluster 402 may simply be two devices 100 working in unison. In some embodiments, the passive capture cluster 402 may be a skid-mounted block with a self-contained system, but may also be constructed on-site.

[0094]

[0101] FIG. 4 is a schematic diagram of a system 400 for passive capture of atmospheric carbon dioxide, comprising multiple passive capture clusters 402. In the context of this specification, a passive capture system 400 is a combination of multiple capture devices 100 or a single capture device, with associated hardware, connections, control systems, and software for internal processing, and ancillary equipment, control systems, and software for post-processing the output of the capture devices 100. To distinguish between the system 400 and the clusters 402, the system 400 is composed of at least one cluster 402, while the cluster 402 is composed of at least two devices 100. Moreover, the passive capture system 400 is a set of capture devices 100 that are particularly tightly connected and organized into one or more clusters 402. For example, passive capture systems may be banded together into a single skid-mounted containerized subsystem. The use of the terms system and cluster overlaps. A passive capture cluster 402 is typically more tightly connected than a passive capture system 400.

[0095]

[0102] The recovery units are interconnected into a passive recovery system 400 that, through coordinated regeneration, can produce a nearly continuous product flow 406. This continuous product flow 406 can be increased by sweeping product gas from a nearly empty unit through a unit that still exhibits a higher loading. For example, in one embodiment, recovery unit 100a of cluster 402 can be nearly empty and have its product gas swept into an adjacent recovery unit 100b (in the same cluster 402) that has a higher loading. Units 100a and 100b are in fluid communication with each other (e.g., unit 100b is in fluid communication with the product outlet 118 of unit 100a) and in some sense share a sweep gas source.

[0096]

[0103] The use of a passive capture system 400 or cluster 402 can provide a continuous product flow 406 that is versatile and can be adjusted to meet changing weather and climate conditions. In some embodiments, the system 400 and / or cluster 402 can include a control system 404 that can replace or operate in conjunction with the control system 328 of the individual devices 100. The control system 404 can be configured to operate the devices in sequence to operate such a system 400 continuously, allowing efficient CO2 upgrade from a typical 400 parts per million relative to ambient air to a few percent, i.e., in the range of 1-10%. An advantage of the systems and methods contemplated herein is that they can operate optimally under changing conditions with minimal energy costs. It should be noted that the control system 404 of the cluster 402 or system 400 can perform all of the operations and measurements contemplated for the control system 328 of the individual devices 100 described above.

[0097]

[0104] In some embodiments, the individual capture units 100 of the passive capture system 400 may be held in place by various means and may be interconnected in a manner that allows for concentrated gas 324 to be removed from one passive capture unit 100 via a series of regenerating capture units 100. Gas handling, water, steam, or power handling connections may be switched as needed between all capture units 100, or between a subset thereof. Optionally, the capture units 100 may be organized into hierarchical structures such as individual capture units 100, clusters 402 of capture units 100, clusters of clusters, systems of clusters, etc.

[0098]

[0105] The passive capture system 400 may include a system of process units to provide a sweep gas to the capture apparatus 100, or alternatively, a system of process units to apply a vacuum to the capture apparatus 100 and draw CO2 therefrom. These process units may include piping, pumps, fans, valves, sensors, actuators, control software, and other components necessary to interconnect the capture apparatus 100. Additionally, the passive capture system 400 may include a system of piping and valves to deliver water to the capture apparatus 100, to collect wastewater, and / or to collect and recirculate water.

[0099]

[0106] Some passive retrieval systems 400 and / or clusters 402 may include shared resources. For example, as shown in FIGURE 4, in some embodiments, multiple passive retrieval devices 100 may share the same actuator 120 to move their respective capture structures 106 between the retrieval configuration 300 and the release configuration 312. This actuator 120 may be shared among multiple devices 100 using mechanical devices such as gears, arms, pulleys, and / or any other mechanical devices known in the art.

[0100]

[0107] In some embodiments, the passive capture system 400 may include a shared system for delivering the release media 316 to multiple capture devices 100, while in other embodiments, each passive capture device 100 may have its own resources. The passive capture system 400 may also include support structures to hold the multiple capture devices 100 in place. The support structures may include, but are not limited to, a foundation, a tent-like structure to hold an upper structure for raising and lowering the capture structure 106, protection from the sun, and panels to direct wind in various ways through the system.

[0101]

[0108] 4, in some embodiments, the passive capture system 400 may further comprise one or more baffles 408 for redirecting airflow to increase exposure to the sorbent material of the capture device 100. In some embodiments, these baffles 408 may be articulated and configured to adjust to changes in ambient conditions (e.g., wind direction, sun position in the sky, weather, etc.). One skilled in the art will recognize that the baffles 408 may be utilized in the context of individual capture devices 100 as well.

[0102]

[0109] Additionally, some passive capture systems 400 and / or clusters 402 may utilize automation systems that may include, but are not limited to, wind / weather measurement and response, CO2 capture monitoring, automatically timed tile 108 and lid movement, water and air control systems, temperature measurement and control, internal flow measurement, timing control to match the function of other capture devices 100 in the same system or cluster, blowdown control, and any other automation contemplated herein with respect to the individual devices 100.

[0103]

[0110] The following discussion is intended to illustrate, rather than limit, the operation of a passive capture device 100 utilizing heat and moisture sensitive sorbent tiles 108 according to one embodiment. The operating cycle of the passive capture device 100 begins with all sorbent tiles 108 inside the release chamber 104 in a closed position with no CO2. (In this context, "no" means lean. There may be residual CO2 present in the sorbent, or even a completely bare sorbent will contain CO2, e.g., as carbonate, if the sorbent swing is between carbonate and bicarbonate.) The lid is raised by the actuator 120, lifting all of the moving tiles 108 out of the overlapping chamber into the capture configuration 300 with all tiles 108 hanging from at least one collapsible support 112. When the lid 114 reaches its top position, all of the sorbent tiles 108 are exposed to air movement. There are gaps between the tiles 108, which allows air to flow across all the tiles 108 and the capture phase begins. The exposure time for the CO2 capture phase may vary based on the weather conditions and the sorbent chosen. In the case of humidity swing, the tiles 108 release some moisture and bind the CO2. This may be the case for other sorbents that are exposed to moisture during regeneration. One reason to expose the sorbent to moisture (e.g., in the form of weak steam) is to prevent the sorbent from expending too much energy to separate the moisture. This is different from humidity swing, where the presence of moisture itself stimulates the release of CO2.

[0104]

[0111] After exposure, the lid 114 is lowered again. As soon as the lid closes the release chamber 104, capture begins. In the humidity swing sorbent example, the sorbent tiles 108 bind enough moisture to cause the release of CO2. The air in the chamber is now enriched in CO2, which is drawn through the product outlet 118. The tiles 108 are raised again when empty, and the cycle of capturing CO2 from the air begins again as the sorbent 110 dries. Condensed water is pumped back to the heat sink or flushed away. To avoid a gradual decrease in CO2 concentration in the product stream 326, multiple capture devices 100 can be bundled together, with the sweep gas flowing from a passive capture device 100 that is nearly empty to one that still has a high equilibrium concentration of CO2. The concentration of the product stream 326 delivered in this way is close to that of a nearly full load of resin.

[0105]

[0112] In some embodiments, the device 100 or cluster 402 of collection devices 100 may be elevated above other equipment to reduce footprint and land use and / or to enhance collection since higher collection increases airflow in some terrains.

[0106]

[0113] In some embodiments, the passive collection system 400 may include panels for guiding the wind. The purpose of these panels or sails is to guide the wind towards or away from the passive collection device 100 to increase the operating range of the passive collection device 100 with respect to wind speed. At low wind speeds, the air is forced into the passive collection device 100, and at high wind speeds, the air is deflected. The panels can also be used with a single collection device 100 outside the context of a system 400 or cluster 402.

[0107]

[0114] According to various embodiments, the passive capture system 400 may also include electrical, sensor, and control systems to power and manage the capture apparatus 100. Some passive capture systems 400 may also include an upgrade system to improve the quality of the product stream 326. In some embodiments, the passive capture system 400 may be configured to deliver a dry CO2 / air mixture with a CO2 concentration in the range of 0.1%-95% or higher. Some passive capture systems 400 may utilize a system for binding the CO2 to a second sorbent, from which pure CO2 may be produced. Other passive capture systems 400 may use a system that starts with a low pressure stream that is nearly pure CO2 and water vapor, which is then dried and compressed to produce a pure concentrated stream of CO2. Still other passive capture systems 400 may use a system that dissolves the CO2 into a carbonate / bicarbonate solution. Some passive capture systems 400 may utilize multiple systems to upgrade the system output. However, it should be apparent to one of ordinary skill in the art that capture apparatus 100 and system 400 are designed to capture CO2 from the atmosphere and provide it in a form useful for downstream applications. Capture apparatus 100 and system 400 are in no way limited by the choice of sorbent material or intended downstream application.

[0108]

[0115] Where the above examples, embodiments, and implementations refer to examples, it should be understood by those skilled in the art that other passive capture devices, systems, and methods, and examples may be mixed with or substituted for the passive capture devices, systems, and methods, and examples provided. Where the above description refers to specific embodiments of passive capture devices, systems, and methods, it should be readily apparent that numerous modifications may be made without departing from the spirit thereof, and that these embodiments and implementations may be equally applied to other carbon dioxide capture devices, systems, and methods. Thus, the disclosed subject matter is intended to encompass all such changes, modifications, and variations within the spirit and scope of the disclosure and the knowledge of those skilled in the art.

Claims

1. 1. An apparatus for passive capture of atmospheric carbon dioxide, comprising: a release chamber having an opening and a sorbent regeneration system; a capture structure connected to the release chamber, the capture structure comprising at least one foldable support and a plurality of tiles connected to and spaced apart therealong, each tile including a sorbent material, the capture structure being movable between a collection configuration and a release configuration; a lid covering the opening of the emission chamber when the capture structure is in the emission configuration; a product outlet in fluid communication with the interior of the discharge chamber and configured to receive a product flow of enriched gas; Equipped with the capture arrangement includes a capture structure extending upwardly from the release chamber to expose at least a portion of the capture structure to an airflow to enable the sorbent material of the plurality of tiles to capture atmospheric carbon dioxide; The release configuration comprises: the at least one foldable support of the capture structure in a folded state; a lid covering the opening of the emission chamber; the plurality of tiles being sufficiently enclosed inside the discharge chamber such that the sorbent regeneration system can act on the plurality of tiles to release captured carbon dioxide from the sorbent material and produce concentrated gas within the discharge chamber; Including, the shape of each of the plurality of tiles is selected from the group consisting of: generally flat, generally flat except for a rim or pad used in the overlap, bowl-shaped, and helmet-shaped; Device.

2. the sorbent material is a humidity swing sorbent material; the sorbent regeneration system comprising an emitting media and an emitting media emitter; the release medium being one of liquid water and steam; 2. The apparatus of claim 1.

3. the sorbent material is a thermal swing sorbent material; the sorbent regeneration system comprises a heat source; 2. The apparatus of claim 1.

4. the heat source is an emitting medium emitter configured to emit steam; 4. The apparatus of claim 3.

5. the discharge chamber further comprising a sweep gas inlet connected to a sweep gas source and configured to introduce a sweep gas into the discharge chamber to displace the enriched gas; An apparatus according to any one of claims 1 to 4.

6. the sweep gas is steam; 6. The apparatus of claim 5.

7. Each tile of the plurality of tiles is substantially planar. An apparatus according to any one of claims 1 to 3.

8. for each tile of the plurality of tiles, the sorbent material includes a plurality of sorbent surfaces cross-connected to a surface of the tile; 8. The apparatus of claim 7.

9. each tile of the plurality of tiles includes a hole; 8. Apparatus according to claim 1 or 7.

10. each tile of the plurality of tiles comprises an upper frame and a lower frame; the sorbent material is sandwiched between the upper frame and the lower frame; 8. Apparatus according to claim 1 or 7.

11. an actuator connected to the capture structure; a control system communicatively connected to the actuator and configured to drive the actuator to move the capture structure between the collection configuration and the release configuration; Further comprising: An apparatus according to any one of claims 1 to 3.

12. and at least one sensor communicatively connected to the control system. the control system is configured to determine at least one ambient condition based on signals received from the at least one sensor, and to autonomously drive the actuator to move the capture structure between the retrieval configuration and the release configuration based on the at least one ambient condition; the at least one ambient condition includes at least one of temperature, humidity, and wind speed; 12. The apparatus of claim 11.

13. and further comprising at least one baffle separated from the capture structure and configured to redirect airflow to increase exposure to the sorbent material.

2. The apparatus of claim 1.

14. preparing a passive capture device for capturing atmospheric carbon dioxide comprising a release chamber and a capture structure by moving the capture structure into a capture configuration with an actuator driven by a control system, the capture structure comprising at least one foldable support and a plurality of tiles connected to and spaced therealong, each tile comprising a sorbent material, the capture configuration including the capture structure extending upwardly from the release chamber; exposing at least a portion of the capture structure to an airflow to enable the sorbent material of the plurality of tiles to capture atmospheric carbon dioxide; actuating the actuator to lower the capture structure into the emission chamber such that the at least one foldable support is folded and the plurality of tiles are completely inside the emission chamber, thereby placing the capture structure in a release configuration; closing the emission chamber with a lid to confine the plurality of tiles inside the emission chamber; regenerating the sorbent material of the plurality of tiles by acting on the sorbent material with a sorbent regeneration system to release the captured carbon dioxide and generate concentrated gas in the release chamber; displacing the enriched gas with a sweep gas introduced into the discharge chamber to discharge a product stream of the enriched gas through a product outlet in fluid communication with the interior of the discharge chamber; Including, the shape of each of the plurality of tiles is selected from the group consisting of: generally flat, generally flat except for a rim or pad used in the overlap, bowl-shaped, and helmet-shaped; Methods for passive capture of atmospheric carbon dioxide.

15. the sorbent material is a humidity swing sorbent material; the sorbent regeneration system comprising an emitting media and an emitting media emitter; the release medium being one of liquid water and steam; The method of claim 14.

16. the sorbent material is a thermal swing sorbent material; the sorbent regeneration system comprises a heat source; The method of claim 14.

17. the heat source is an emitting medium emitter configured to emit steam; 17. The method of claim 16.

18. determining at least one ambient condition at a site of the passive collection device based on signals received from at least one sensor communicatively connected to the control system; determining an optimal exposure time for the capture structure based on the at least one ambient condition; Further comprising: The method according to any one of claims 14 to 16.

19. the sweep gas is one of air, nitrogen, water vapor, and steam; The method of claim 14.

20. at least one passive collection cluster, Each passive capture cluster comprises at least two passive capture devices, each passive capture device comprising: a release chamber having an opening and a sorbent regeneration system; a capture structure connected to the release chamber, the capture structure comprising at least one foldable support and a plurality of tiles connected to and spaced apart therealong, each tile including a sorbent material, the capture structure being movable between a collection configuration and a release configuration; a lid covering the opening of the emission chamber when the capture structure is in the emission configuration; an actuator connected to the capture structure; a product outlet in fluid communication with the interior of the discharge chamber and configured to receive a product flow of enriched gas; At least one passive collection cluster comprising: a control system communicatively connected to each passive collection cluster and configured to drive the actuators to move the capture structure of at least one passive collection device between the collection configuration and the release configuration; Equipped with the product outlets of each passive collection device in the same cluster are in fluid communication; for each passive capture device, the capture arrangement includes a capture structure extending upwardly from the release chamber to expose at least a portion of the capture structure to an airflow to enable the sorbent material of the plurality of tiles to capture atmospheric carbon dioxide; For each passive retrieval device, the release configuration comprises: the at least one foldable support of the capture structure in a folded state; a lid covering the opening of the emission chamber; the plurality of tiles being sufficiently enclosed inside the discharge chamber such that the sorbent regeneration system can act on the plurality of tiles to release captured carbon dioxide from the sorbent material and produce concentrated gas within the discharge chamber; Including, the shape of each of the plurality of tiles is selected from the group consisting of: generally flat, generally flat except for a rim or pad used in the overlap, bowl-shaped, and helmet-shaped; A system for passive capture of atmospheric carbon dioxide.

21. the at least two passive retrieval devices of each cluster share the same actuator; 21. The system of claim 20.

22. the release chambers of each passive collection device in the same cluster are in fluid communication; The concentrated gas of one recovery unit may be swept through the discharge chamber of an adjacent recovery unit.

22. A system according to claim 20 or 21.

23. and at least one sensor communicatively connected to the control system. The control system comprises: determining at least one ambient condition based on signals received from the at least one sensor; autonomously actuating at least one actuator to move at least one capture structure between the collection configuration and the release configuration based on the at least one ambient condition. It is configured as follows: the at least one ambient condition includes at least one of temperature, humidity, and wind speed; A system according to any one of claims 20 to 22.

24. the control system is configured to sequence the passive capture devices to produce a continuous product flow of enriched gas.

24. The system of claim 23.

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