Systems and methods for carbon dioxide capture via desublimation and sublimation stages in a heat exchanger

Abstract

A system is provided that includes a carbon capture system. The carbon capture system may include a heat exchanger including a plurality of passages. The carbon capture system also includes a coolant subsystem coupled to the heat exchanger, wherein the coolant subsystem includes a coolant fluid configured to indirectly cool and deposit carbon dioxide (CO2) from a flue gas stream into a CO2 deposit within a first subset of the plurality of passages during a desublimation stage, wherein the coolant fluid is configured to circulate a coolant fluid different than the flue gas stream. The carbon capture system also includes a purge subsystem coupled to the heat exchanger, wherein the purge subsystem is configured to sublimate and purge the CO2 deposit from the first subset of the plurality of passages during a sublimation stage.

Description

IS24.1354-WO-PCTSYSTEMS AND METHODS FOR CARBON DIOXIDE CAPTURE VIA DESUBLIMATION AND SUBLIMATION STAGES IN A HEAT EXCHANGERCROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims priority to and the benefit of U.S. Provisional Patent Application No. 63 / 736,201 filed December 19, 2024, which is incorporated herein by reference in its entirety.BACKGROUND

[0002] The present disclosure generally relates to systems and methods for capturing undesirable gases (e.g., carbon dioxide) from a flue gas.

[0003] This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present disclosure, which are described and / or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present disclosure. Accordingly, it may be understood that these statements are to be read in this light, and not as admissions of prior art.

[0004] Undesirable gases such as carbon dioxide (CO2), carbon monoxide (CO), nitrogen dioxide (NO2), and / or sulfur dioxide (SO2) pollute the atmosphere. Industrial plants often combust hydrocarbon-containing materials, such as coal, oil, and natural gas, to generate heat and / or power for various equipment. Flue gas is generated as a byproduct of the combustion process and may be treated prior to being released into the atmosphere. For example, a carbon capture system may capture a portion of the undesirable gases to comply with emissions requirements, to comply with regulations, or to earn credits. However, a need exists to increase the efficiency of carbon capture systems, such as to address increasingly stringent emissions requirements and associated costs of operating the carbon capture systems.SUMMARYIS24.1354-WO-PCT

[0005] A summary of certain embodiments disclosed herein is set forth below. It should be understood that these aspects are presented merely to provide the reader with a brief summary of these certain embodiments and that these aspects are not intended to limit the scope of this disclosure. Indeed, this disclosure may encompass a variety of aspects that may not be set forth below.

[0006] In certain embodiments, a system is provided that includes a carbon capture system. The carbon capture system may include a heat exchanger including a plurality of passages, a coolant subsystem coupled to the heat exchanger, wherein the coolant subsystem includes a coolant fluid configured to indirectly cool and deposit carbon dioxide (CO2) from a flue gas stream into a CO2 deposit within a first subset of the plurality of passages during a desublimation stage, wherein the coolant fluid is configured to circulate a coolant fluid different than the flue gas stream. The carbon capture system may also include a purge subsystem coupled to the heat exchanger, wherein the purge subsystem is configured to sublimate and purge the CO2 deposit from the first subset of the plurality of passages during a sublimation stage.

[0007] In certain embodiments, a method is provided that includes indirectly cooling, via a coolant subsystem including a coolant fluid, a first subset of a plurality of passages of a heat exchanger during a desublimation stage, flowing a flue gas stream through the first subset of the plurality of passages during the desublimation stage, wherein the flue gas stream is different than the coolant stream. The method also includes depositing a carbon dioxide (CO2) deposit from the flue gas stream in the first subset of the plurality of passages during the desublimation stage, and sublimating and purging the CO2 deposit from the first subset of the plurality of passages during a sublimation stage.

[0008] In certain embodiments, a gas treatment system is provided that includes a carbon capture system. The carbon capture system include a heat exchanger including a plurality of passages, a coolant subsystem coupled to the heat exchanger, wherein the coolant subsystem includes a coolant fluid configured to indirectly cool and deposit carbon dioxide (CO2) from a flue gas stream into a CO2 deposit within a first subset of the plurality of passages during a desublimation stage, and wherein the coolant subsystem is a closed loop, wherein the coolantIS24.1354-WO-PCT subsystem is configured to circulate a coolant fluid through a second subset of the plurality of passages, wherein the first and second subsets of the plurality of passages are different from one another, and wherein the coolant fluid is different than the flue gas stream. The carbon capture system also includes a purge subsystem coupled to the heat exchanger, wherein the purge subsystem is configured to sublimate and purge the CO2 deposit from the first subset of the plurality of passages during a sublimation stage.

[0009] Various refinements of the features noted above may exist in relation to various aspects of the present disclosure. Further features may also be incorporated in these various aspects as well. These refinements and additional features may exist individually or in any combination. For instance, various features discussed below in relation to one or more of the illustrated embodiments may be incorporated into any of the above-described aspects of the present disclosure alone or in any combination. The brief summary presented above is intended only to familiarize the reader with certain aspects and contexts of embodiments of the present disclosure without limitation to the claimed subject matter.BRIEF DESCRIPTION OF THE DRAWINGS

[0010] These and other features, aspects, and advantages of the present disclosure will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:

[0011] FIG. 1 is a block diagram of an embodiment of an industrial plant including a production facility and a gas treatment system, wherein the gas treatment system enables a gas capture process via a heat exchanger coupled to coolant and purge subsystems;

[0012] FIG. 2 is a block diagram of an embodiment of the gas treatment system of FIG. 1, further illustrating the gas capture process having a desublimation stage, a sublimation stage, and a precooling stage via heat transfer in the heat exchanger;

[0013] FIG. 3 is a phase diagram of carbon dioxide under various phases in support of the gas capture process of FIGS. 1 and 2, in accordance with aspects of the present disclosure;IS24.1354-WO-PCT

[0014] FIG. 4 is a schematic of an embodiment of the gas treatment system of FIGS. 1 and 2, further illustrating a configuration of the coolant and purge subsystems coupled to the heat exchanger, wherein the purge subsystem includes a heat exchanger and a compressor;

[0015] FIG. 5 is a schematic of an embodiment of the gas treatment system of FIGS. 1, 2, and 4, further illustrating a configuration of the coolant and purge subsystems coupled to the heat exchanger, wherein the coolant subsystem includes a cryogenic cooler;

[0016] FIG. 6 is a schematic of an embodiment of the gas treatment system of FIGS. 1 and 2, further illustrating a configuration of the coolant and purge subsystems coupled to the heat exchanger, wherein the coolant subsystem includes a cryogenic cooler and the purge system includes a pump;

[0017] FIG. 7 is a flow chart of an embodiment of a process for operating a gas treatment system of FIGS. 1, 2, and 4-6, illustrating operation of the desublimation and sublimation stages via multiple passages of the heat exchanger; and

[0018] FIG. 8 is a flow chart of an embodiment of a process for operating a gas treatment system of FIGS. 1, 2, and 4-6, illustrating operation of the desublimation and sublimation stages via multiple passages of the heat exchanger.DETAILED DESCRIPTION

[0019] Certain embodiments commensurate in scope with the present disclosure are summarized below. These embodiments are not intended to limit the scope of the disclosure, but rather these embodiments are intended only to provide a brief summary of certain disclosed embodiments. Indeed, the present disclosure may encompass a variety of forms that may be similar to or different from the embodiments set forth below.

[0020] As used herein, the term “coupled” or “coupled to” may indicate establishing either a direct or indirect connection (e.g., where the connection may not include or include intermediate or intervening components between those coupled), and is not limited to either unless expressly referenced as such. The term “set” may refer to one or more items.IS24.1354-WO-PCTWherever possible, like or identical reference numerals are used in the figures to identify common or the same elements. The figures are not necessarily to scale and certain features and certain views of the figures may be shown exaggerated in scale for purposes of clarification.

[0021] As used herein, the terms “inner” and “outer”; “up” and “down”; “upper” and “lower”; “upward” and “downward”; “above” and “below”; “inward” and “outward”; and other like terms as used herein refer to relative positions to one another and are not intended to denote a particular direction or spatial orientation. The terms “couple,” “coupled,” “connect,” “connection,” “connected,” “in connection with,” and “connecting” refer to “in direct connection with” or “in connection with via one or more intermediate elements or members.

[0022] Furthermore, when introducing elements of various embodiments of the present disclosure, the articles “a,” “an,” and “the” are intended to mean that there are one or more of the elements. The terms “comprising,” “including,” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements. Additionally, it should be understood that references to “one embodiment,” “an embodiment,” or “some embodiments” of the present disclosure are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features. Furthermore, the phrase A “based on” B is intended to mean that A is at least partially based on B. Moreover, unless expressly stated otherwise, the term “or” is intended to be inclusive (e.g., logical OR) and not exclusive (e.g., logical XOR). In other words, the phrase A “or” B is intended to mean A, B, or both A and B.

[0023] As used herein, the term “processing system” refers to an electronic computing device such as, but not limited to, a single computer, virtual machine, virtual container, host, server, laptop, and / or mobile device, or to a plurality of electronic computing devices working together to perform the function described as being performed on or by the computing system. As used herein, the term “medium” refers to one or more non-transitory, computer-readable physical media that together store the contents described as being stored thereon.IS24.1354-WO-PCTEmbodiments may include non-volatile secondary storage, read-only memory (ROM), and / or random-access memory (RAM).

[0024] In addition, as used herein, the terms “real time”, ’’real-time”, or “substantially real time” may be used interchangeably and are intended to describe operations (e.g., computing operations) that are performed without any human-perceivable interruption between operations. For example, as used herein, data relating to the systems described herein may be collected, transmitted, and / or used in control computations in “substantially real time” such that data readings, data transfers, and / or data processing steps occur once every second, once every 0.1 second, once every 0.01 second, or even more frequent, during operations of the systems (e.g., while the systems are operating). In addition, as used herein, the terms “continuous”, “continuously”, or “continually” are intended to describe operations that are performed without any significant interruption. For example, as used herein, control commands may be transmitted to certain equipment every five minutes, every minute, every 30 seconds, every 15 seconds, every 10 seconds, every 5 seconds, or even more often, such that operating parameters of the equipment may be adjusted without any significant interruption to the closed-loop control of the equipment. In addition, as used herein, the terms “automatic”, “automated”, “autonomous”, and so forth, are intended to describe operations that are performed are caused to be performed, for example, by a computing system (i.e., solely by the computing system, without human intervention). Indeed, although certain operations described herein may not be explicitly described as being performed continuously and / or automatically in substantially real time during operation of the computing system and / or equipment controlled by the computing system, it will be appreciated that these operations may, in fact, be performed continuously and / or automatically in substantially real time during operation of the computing system and / or equipment controlled by the computing system to improve the functionality of the computing system (e.g., by not requiring human intervention, thereby facilitating faster operational decision-making, as well as improving the accuracy of the operational decision-making by, for example, eliminating the potential for human error), as described in greater detail herein.IS24.1354-WO-PCT

[0025] The present disclosure is generally directed towards gas treatment systems and methods for capturing one or more undesirable gases from a flue gas using thermal variations in different passages of a heat exchanger. In the following discussion, the undesirable gases may include carbon oxides (COx) (e.g., carbon dioxide (CO2) and carbon monoxide (CO)), nitrogen oxides (NOx) (e.g., nitrogen dioxide (NO2), and sulfur oxides (SOx) (e.g., sulfur dioxide (SO2)), and / or any other gases sought to be removed from the flue gas. Although the following discussion uses CO2 as an example, the disclosed embodiments are intended to cover any undesirable gases. In certain embodiments, the gas treatment system include one or more heat exchangers coupled to a coolant subsystem and a purge subsystem. The heat exchanger includes a plurality of passages that are independent from one another, wherein some of the passages are used only for cooling the heat exchanger via the coolant subsystem, and some of the passages are used for capturing the undesirable gases from the flue gas. The coolant subsystem may include a cryogenic coolant subsystem configured to cool the heat exchanger and provide indirect cooling to the flue gas. The gas treatment system is configured to use one or more passages of the heat exchanger for capturing the undesirable gases in a plurality of stages (e.g., a desublimation stage, a sublimation stage, and a precooling stage) separate from passages being cooled by the coolant subsystem. As discussed below, the plurality of stages are controlled by a controller, which may control the temperature, pressure, and fluid flow through the passages used for capturing the undesirable gases. The controller is configured to transition the gas treatment system between the stages in the one or more passages of the heat exchanger by switching fluid connections with the one or more passages, such as by switching between a flue gas source for the desublimation stage, the purge subsystem for the sublimation stage, and the coolant subsystem for the precooling stage. The coolant fluid of the coolant subsystem is maintained to be different from the flue gas.

[0026] In the desublimation stage (e.g., deposition stage or solidification stage), the controller selectively couples the flue gas source to the one or more passages of the heat exchanger to direct the flue gas through the passages. The controller is configured to control the flow rate of flue gas through the passages, the temperature profile in the passages via control of the coolant subsystem, and a time duration of the desublimation stage. TheIS24.1354-WO-PCT controller is specifically configured to control the cooling provided by the coolant subsystem to cause the undesirable gases (e.g., CO2) to solidify (e.g., via desublimation or deposition) into solid deposits (e.g., solid CO2) along walls of the one or more passages. The desublimation or deposition of the undesirable gases (e.g., CO2) is a transition of the undesirable gases directly from a gas state to a solid state without passing through a liquid state. The temperature profile may be based on the partial pressure of the undesirable gases (e.g., CO2) within the flue gas. That is, flue gas generated from various sources and / or various fuel sources may include CO2 at varying partial pressures. In this way, the controller is configured to vary the temperature profile of the passages to improve the efficiency of CO2 capture. For example, the passages of the heat exchanger receiving flue gas may be cooled to a temperature based on the partial pressure of CO2, wherein the temperature is lower for flue gases with a higher partial pressure of CO2 and the temperature is higher for flue gases with a lower partial pressure of CO2. As such, the gas treatment system may be controlled by the controller to extract CO2 at various concentrations within the flue gas, thereby improving operations and flexibility of CO2 capture from flue gases of various sources. The controller may be configured to control the gas treatment system in the same manner for any undesirable gases as described herein.

[0027] In the sublimation stage (e.g., gasification or solid-to-gas conversion stage), the controller selectively couples the purge subsystem to the one or more passages of the heat exchanger to enable a purge flow through the passages. The controller is configured to control the flow rate of the purge flow through the passages, the temperature in the passages, the pressure in the passages, and a time duration of the sublimation stage. The purge subsystem uses a temperature differential and / or a pressure differential to cause the solid deposits (e.g., solid CO2) to gasify (e.g., via sublimation) and flow out of the one or more passages for gas capture. The sublimation of the solid deposits (e.g., solid CO2) is a transition of the solid deposits directly from a solid state to a gas state without passing through a liquid state. As discussed in detail below, the one or more passages used for gas capture may be alternatingly coupled to the flue gas source and the purge subsystem to alternatingly operate in a desublimation stage followed by a sublimation stage. In some embodiments, the one or more passage may further be used with the precooling stage.IS24.1354-WO-PCT

[0028] In the precooling stage, the controller selectively cools the one or more passages of the heat exchanger via the coolant subsystem after the sublimation stage and before the desublimation stage. The controller is configured to control the temperature in the passages and a time duration of the precooling stage. In some embodiments, the gas treatment system may exclude the precooling stage. Advantageously, the disclosed embodiments avoid any contamination of the gas capture process with the coolant used in the coolant subsystem, and avoid any contamination of the coolant subsystem with the gas capture process. That is, the coolant fluid of the coolant subsystem is maintained to be different from the flue gas of the gas capture process.

[0029] In operation, the gas treatment system operates to extract the undesirable gases from the flue gas by desublimating the undesirable gases into solid deposits in the passage of the heat exchanger, sublimate the solid deposits into a gas and purge the gas from the passage of the heat exchanger, and precool the passage of the heat exchanger to prepare for additional CO2 extraction. It should be noted, in some embodiments the stages of the gas treatment system may extract, sublimate, purge, and / or store one or more additional gases from the flue gas. For example, the additional gases may include NOXgases and / or SOXgases within the flue gas. The gas treatment system may concurrently and / or subsequently perform the stages in one or more additional passages of the heat exchanger. In certain embodiments, the sublimation stage may include cooling one or more coolant passages of the heat exchanger with a coolant fluid. The coolant fluid may be provided by the coolant subsystem. The coolant fluid may cool the coolant passages via a closed loop system. In this manner, the coolant fluid may be recycled for additional cooling of the heat exchanger. The cooled extraction passages of the heat exchanger may receive a flue gas including CO2, NOX, SOX, or a combination thereof, from a flue gas source. The coolant passages may indirectly cool one or more extraction passages of the heat exchanger to or below a sublimation point. The sublimation point may be based on the partial pressure of CO2 in the flue gas. As the flue gas passes through the cooled extraction passages, the CO2 may be extracted (e.g., sublimated) onto one or more walls of the cooled extraction passages. Extraction of the CO2 from the flue gas source may proceed until the cooled extraction passages meet a threshold loading value. The threshold loading value may be based on a loading capacity of the cooledIS24.1354-WO-PCT extraction passages. Additionally and / or alternatively, extraction of NOX, and / or SOxmay be performed based on the sublimation point and one or more operational procedures of the gas treatment system in addition to or instead of CO2. In some embodiments, a treated flue gas (e.g., substantially free of C02,N0x, and / or SOX) may be output from the cooled extraction passages as a result of extraction of CO2, NOX, SOX, or a combination thereof, from the flue gas. As discussed herein, the treated flue gas may be substantially free of CO2, NOX, and / or SOXsuch that the treated flue gas satisfies local emissions regulations.

[0030] In certain embodiments, the gas treatment system may transition from the desublimation stage to the sublimation stage. Transition between the sublimation stage and desublimation stage may be based on the gas treatment system detection of the threshold loading value based on the loading capacity of the extraction passages. In some instances, transition between the sublimation stage and desublimation stage may be based on an elapsed period of time and / or sensor feedback data generated by one or more sensors of the gas treatment system. The desublimation stage may receive a purge fluid from the purge subsystem. The purge fluid may include a fluid at a temperature greater than the sublimation point of CO2. For example, the purge fluid may include liquid CO2, gaseous CO2, or a combination thereof. In some instances, the sublimation point may be selected based on the sublimation point of NOXand / or SOXin combination with or instead of CO2. The purge fluid may extract (e g., sublimate) the CO2,NOX, SOX, or a combination thereof, from the extraction passages of the heat exchanger and output the extracted fluid (e.g., CO2, NOX, SOX, or a combination thereof) and purge fluid. The purge subsystem may store the extracted fluid and the purge fluid. For example, the extracted fluid may be stored in a storage tank. Additionally and / or alternatively, the purge subsystem may use pressure to extract the CO2 deposited on the walls of the extraction passages. For example, a vacuum pump may be used to generate a pressure differential to extract the CO2 from the extraction passages of the heat exchanger and store the CO2. In some embodiments, the gas treatment system may use a combination of temperature and pressure to extract the CO2 from the extraction passages.

[0031] In some embodiments, the gas treatment system may transition from the sublimation stage to the precooling stage. However, it should be noted that in someIS24.1354-WO-PCT embodiments, the gas treatment system may transition directly from the sublimation stage to the desublimation stage. The precooling stage may be used to precool the one or more extraction passages by indirectly cooling the extraction passages. Precooling of the one or more extraction passages may be executed by the coolant subsystem. The coolant subsystem may receive coolant fluid at the coolant passages and indirectly cool the extraction passages of the heat exchanger via various heat transfer mechanisms (e.g., convective and conductive heat transfer). Precooling of the extraction passages may improve an operating efficiency of the gas treatment system by reducing energy consumption. In certain embodiments, the precooling stage may continue until the temperature of the extraction passages meets a threshold temperature and / or for a predetermined amount of time. The gas treatment system may transition from the precooling stage to the desublimation stage and extract CO2 from the flue gas.

[0032] In some embodiments, the coolant subsystem of the gas treatment system may indirectly cool passages of the heat exchanger using various pieces of equipment. For example, the coolant subsystem may include a refrigeration unit, a cryogenic cooler (e.g., cryo-cooler), one or more additional coolant devices, or a combination thereof. In certain embodiments, the cryo-cooler of the coolant subsystem may be designed to generate a cryogenic fluid at cryogenic temperatures. The cryo-cooler may include an expander, a compressor, an aftercooler, or a combination thereof. In certain embodiments, the cryogenic fluid may include an inert gas, such as a noble gas (e.g., argon, helium, neon, etc.), nitrogen, CO2, or any combination thereof. The coolant subsystem may be operated separately or with the heat exchanger of the gas treatment system.

[0033] In certain embodiments, the purge subsystem may include a purge fluid tank, a secondary heat exchanger, a compressor, a storage tank, a cryo-pump, a vacuum pump, or a combination thereof. The purge subsystem may be configured to desublimate CO2 from the extraction passages based on a change in temperature and / or a change in pressure. That is, the purge subsystem may provide purge fluid at a threshold temperature to desublimate the CO2 and / or apply a threshold pressure to extract the CO2 from the extraction passages. The purge fluid may be heated to the threshold temperature via the secondary heat exchanger.IS24.1354-WO-PCTThe heated purge fluid may be pumped through the extraction passages causing the CO2 to desublimate. In some instances, the extracted CO2 is passed through the cryo-pump to form a CO2 solid for storage. Additionally and / or alternatively, the extracted CO2 may be stored as a liquid or gas in a storage cylinder. In some embodiments, a portion of the extracted CO2 may be used to extract CO2 from one or more additional extraction passages of the heat exchanger.

[0034] In certain embodiments, the heat exchanger of the gas treatment system may include a plurality of passages. The passages may be designated as extraction passages or coolant passages. It may be advantageous to maintain separate extraction passages and coolant passages to ensure that the purge subsystem and the coolant subsystem maintain distinct closed loops. That is, by separating fluid passages of the purge subsystem and the coolant subsystem, the gas treatment system may avoid contamination between said subsystems, increasing operational efficiency and reducing maintenance needs of the gas treatment system when compared to previously available technologies. In some embodiments, the gas treatment system may include a plurality of extraction passages. The extraction passages may be operated simultaneously or concurrently to one another. For example, a first extraction passage may operate in the sublimation stage while a second extraction passage may operate in the desublimation stage. Additionally and / or alternatively, the first extraction passage may operate in the desublimation stage while a third extraction passage may receive the treated gas from the first extraction passage and output the treated gas.

[0035] In some embodiments, the gas treatment system may include one or more coolant passages. A first coolant passage may receive the coolant fluid (e.g., cryogenic fluid) from the refrigeration unit, the cryo-cooler, or a combination thereof. The coolant fluid may directly cool the first coolant passage and output a fluid to the compressor and the aftercooler. A second coolant passage may receive the fluid direct the fluid back to the refrigeration unit, the cryo-cooler, or a combination thereof. A fluid path of the coolant fluid may be configured to reduce cooling requirements of the coolant fluid by cycling the coolant fluid between the first and second coolant passages.IS24.1354-WO-PCT

[0036] In some embodiments, the gas treatment system may include one or more sensors positioned within passages of the heat exchanger, the purge subsystem, the coolant subsystem, one or more additional components, or a combination thereof. The sensors may be used to collect operational data of the gas treatment system. In some embodiments, the operational data may be used to control components of the gas treatment system to increase operational efficiency by reducing energy consumption and / or improve efficiency of extracting CChfrom the flue gas. In certain embodiments, the operational data may be used to establish an operating procedure for the gas treatment system. For example, flue gas from a particular source may be provided to the gas treatment system and the operating procedure may be determined over a first period of time (e.g., startup). The operational data may be used to establish transition times between stages of the gas treatment system based on the partial pressure of extracted CCh in flue gas from the particular source. In this manner, the operational procedure may include operational parameters of the gas treatment system based on the first period of time. As such, the gas treatment system may be operated according to the operational procedure during a second period of time (e.g., nominal operation).

[0037] In some embodiments, the flue gas received for processing by the gas treatment system may be pretreated by one or more pretreatment units, such as one or more separators, filters, or a combination thereof. For example, one or more components of the flue gas may be removed from the flue gas before introducing the flue gas into the extraction passages of the heat exchanger. In certain embodiments, moisture may be removed from the flue gas during pretreatment. In some embodiments, the flue gas may be compressed after pretreatment before introduction into the heat exchanger to overcome a pressure drop in the gas treatment system. For example, the flue gas may be compressed using a blower, a compressor, or a combination thereof.

[0038] With the foregoing in mind, FIG. 1 is a block diagram of an embodiment of an industrial plant 10 including a production facility 12 and a gas treatment system 14, in accordance with an embodiment of the present disclosure. The industrial plant 10 may be coupled to a controller 16 configured to control operation of the production facility 12 and / or the gas treatment system 14. As discussed below, the gas treatment system 14 is configuredIS24.1354-WO-PCT to capture CChfrom a fluid stream. The fluid stream may be a flue gas stream 18 generated by the production facility 12 one or more additional fluid streams, or a combination thereof. The gas treatment system 14 may be used to capture CO2 and output a captured fluid stream 22 and a treated fluid stream 24 (e.g., treated flue gas stream). In some embodiments, the captured fluid stream 22 may be directed to a storage tank and / or a pipeline 26. The captured fluid stream 22 may include CO2 captured from the flue gas stream 18.

[0039] In some embodiments, the production facility 12 may include an oil and / gas production facility, a refinery, a combustion system (e g., a furnace, a boiler, an engine, etc.) that combusts various fuels (e.g., gas, liquid, and / or solid fuels), a reactor, a natural gas combined cycle (NGCC) power plant, a power plant, a cement plant, a lithium extraction facility, a storage facility, and the like. The production facility 12 may include various equipment that may produce flue gas. It should be noted, the production facility 12 disclosed herein may be located at a site of the gas treatment system 14 and / or one or more remote locations. The production facility 12 may produce the flue gas stream 18 with various concentrations of undesirable gases (CO2. NO , SOX, etc.).

[0040] In some embodiments, the gas treatment system 14 may include one or more heat exchangers 28, a coolant subsystem 30, a purge subsystem 32, and / or one or more additional components. The gas treatment system 14 may be used to control desublimation (e.g., extraction, solidification) and sublimation of CO2 from the flue gas stream 18. The heat exchangers 28 may include a plurality of passages. The passages may include one or more extraction passages, one or more coolant passages, one or more additional passages, or a combination thereof. The coolant subsystem 30 of the gas treatment system 14 may cool the one or more coolant passages with a coolant fluid. The coolant passages may be used to indirectly cool the one or more extraction passages of the heat exchangers 28. In certain embodiments, CO2 extracted from the flue gas stream 18 may be removed from the extraction passages of the heat exchangers 28 by the purge subsystem 32.

[0041] In some embodiments, the controller 16 may be communicatively coupled to one or more sensors 42, one or more additional components of the production facility 12 and / or the gas treatment system 14 of the industrial plant 10. The controller 16 may include aIS24.1354-WO-PCT processor 34, a memory 36, instructions 38, and communication circuitry 40 configured to communicate with sensors and various equipment of the industrial plant 10. For example, the controller 16 may be configured to receive sensor feedback from one or more sensors 42 coupled to the production facility 12, the gas treatment system 14, and / or additional components of the industrial plant 10 and control the equipment based on sensor feedback data, operating modes, user inputs, operational procedures, or any combination thereof. The controller 16 may communicate with the components directly and / or through the network in accordance with present embodiments. In certain embodiments, flow data may be automatically communicated from the sensors 42 to the controller 16 for analysis in realtime, thereby enabling real-time responses (e.g., adjusting flow rates of the gas treatment system 14, initiating shut-down procedures, controlling emergency procedures, etc.) to information obtained from analysis of the flow data.

[0042] The communication circuitry 40 may be a wireless or wired communication component (e.g., circuitry) that may facilitate communication between the controller 16, various types of devices, components of the production facility 12, the gas treatment system 14, the network, and the like. Additionally, the communication circuitry 40 may facilitate data transfer to the controller 16, such that the controller 16 may receive data from the other components depicted in FIG. 1 and the like. The communication circuitry 40 may use a variety of communication protocols, such as Open Database Connectivity (ODBC), TCP / IP Protocol, Distributed Relational Database Architecture (DRDA) protocol, Database Change Protocol (DCP), HTTP protocol, other suitable current or future protocols, or combinations thereof.

[0043] The processor 34 may include single-threaded processor(s), multi -threaded processor(s), or both. The processor 34 may process instructions stored in the memory 36. The processor 34 may also include hardware-based processor(s) each including one or more cores. The processor 34 may include general purpose processor(s), special purpose processor(s), or both. The processor 34 may be communicatively coupled to other internal components (such as the communication circuitry 40, the data storage, the I / O ports, and the display). The memory 36 and the data storage may be any suitable articles of manufactureIS24.1354-WO-PCT that can serve as media to store processor-executable code, data, or the like. These articles of manufacture may represent computer-readable media (e.g., any suitable form of memory or storage) that may store the processor-executable code used by the processor 34 to perform the presently disclosed techniques. As used herein, applications may include any suitable computer software or program that may be installed onto the controller 16 and executed by the processor 34. The memory 36 and the data storage may represent non-transitory computer-readable media (e.g., any suitable form of memory or storage) that may store the processor-executable code used by the processor 34 to perform various techniques described herein. It should be noted that non-transitory merely indicates that the media is tangible and not a signal.

[0044] In some embodiments, the sensors 42 may measure one or more parameters (e.g., fluid parameters), such as a fluid temperature, a fluid pressure, a fluid flow rate, a fluid composition, or any combination thereof, as fluid enters and / or exits the gas treatment system 14. Thus, the sensors 42 may include temperature sensors, pressure sensors, flow rate sensors, fluid composition sensors, or a combination thereof. In some embodiments, the sensors 42 may include a fluid test meter, such as a multiphase flow meter (e.g., using full gamma spectroscopy) configured to measure a flowrate of fluid flowing within the gas treatment system 14. The sensors 42 may include a plurality of sensor modules, wherein a first module may be a flow meter and a second module may be a conductivity sensor, a pressure sensor, and the like. The sensors 42 may provide sensor feedback data related to one or more parameters of fluid flow through one or more actuator controlled valves, passages of the heat exchangers 28, and the like. The actuator controlled valves may include one or more gate valves, ball valves, flapper valves, needle valves, butterfly valves, diaphragm valves, pinch valves, choke valves, or any combination thereof. As discussed in detail below, the actuator controlled valves include actuators (e.g., electric actuators, hydraulic actuators, or pneumatic actuators) configured to move the valves between open and closed positions. The actuator controlled valves may be controlled based on a variety of sensor feedback from the sensors 42. For example, the sensors 42 may include surface sensors (Internet of Things (loT) sensors, gauges, and so forth. The sensors 42 may be usedIS24.1354-WO-PCT to control actuation of the actuator controlled valves to control fluid from to or from the gas treatment system 14.

[0045] It should be noted that the components described above with regard to the production facility 12 and the gas treatment system 14 are exemplary components and the industrial plant 10 may include additional or fewer components as shown.

[0046] FIG. 2 is a block diagram of an embodiment of the gas treatment system 14, in accordance with an embodiment of the present disclosure. The gas treatment system 14 may include one or more heat exchangers 28 with one or more extraction passages 66, one or more coolant passages 68, and / or one or more additional passages. The gas treatment system 14 includes a desublimation stage 60, a sublimation stage 62, a precooling stage 64, or a combination thereof. It should be noted, the gas treatment system 14 may include one or more additional stages. The desublimation stage 60 may be used to capture CO2 in the extraction passages 66. The sublimation stage 62 may be used to purge the captured CO2 from the extraction passages 66. The precooling stage 64 may be used to precool the extraction passages 66 via the coolant subsystem 30.

[0047] In some embodiments, the desublimation stage 60 may receive the flue gas stream 18 at the extraction passages 66 of the heat exchanger 28. The flue gas stream 18 may include undesirable gases such as CCh.NOx, and / or SOX. The undesirable gases may be captured in the extraction passages 66 by desublimating (e.g., converting gaseous CO2 to solid CO2), thereby generating a solid CO2 deposit 70. It should be noted, the CO2 deposit 70 may include one or more additional components such as NOX, and / or SOX. The treated fluid stream 24 may be output from the extraction passages 66 after desublimation of the CO2 deposit 70. The coolant subsystem 30 may cool the one or more coolant passages 68. The coolant passages 68 may be cooled by a coolant fluid 72 that is different from the flue gas stream 18. The coolant passages 68 may cool the coolant passages 68 via a closed loop system. In this manner, the coolant fluid may be recycled via a recycled coolant fluid 74. The recycled coolant fluid 74 may be recycled to improve efficiency by reducing energy consumption from continuous cooling. In some embodiments, the coolant passages 68 may indirectly cool the one or more extraction passages 66 via various heat transfer mechanisms (e.g., convectiveIS24.1354-WO-PCT and conductive heat transfer). That is, the coolant passages 68 and the extraction passages 66 may be positioned proximate to each other within the heat exchanger 28, such that the fluids in the passages 66 and 68 are isolated from one another while enabling indirect heat transfer between the fluids.

[0048] In certain embodiments, the gas treatment system 14 may transition from the desublimation stage 60 to the sublimation stage 62 to purge the CO2 deposit 70 from the extraction passages 66. The purge subsystem 32 of the gas treatment system 14 may provide a purge fluid 76 (e.g., purge gas) to the extraction passages 66. The purge fluid 76 may include fluid at a temperature greater than the sublimation point of the CO2 deposit 70. The purge fluid may extract the CO2 deposit 70 through sublimation of the CO2 deposit 70 from a solid to a gas. As such, the purge subsystem 32 may receive a stream 78 of sublimated CO2 fluid (e.g., CO2 gas) and the purge fluid 76 from the extraction passages 66 of the heat exchanger 28. In some embodiments, the coolant subsystem 30 may stop flow of the coolant fluid 72 through the coolant passages 68 during the sublimation stage 62. Alternatively, the coolant subsystem 30 may continue to flow the coolant fluid 72 through the coolant passages 68 during operation of the sublimation stage 62 of the gas treatment system 14.

[0049] In some embodiments, the gas treatment system 14 may transition from the sublimation stage 62 to the precooling stage 64. The precooling stage 64 may be used to precool the one or more extraction passages 66 (e.g., after the sublimation stage 62 and before the desublimation stage 60) by indirectly cooling the extraction passages 66 via indirect heat transfer with the coolant passages 68. In this manner, the extraction passages 66 and the coolant passages 68 may be positioned proximate to each other. The coolant subsystem 30 may receive the coolant fluid 72 at the coolant passages 68 and indirectly cool the extraction passages 66 of the heat exchanger 28 to improve an operating efficiency of the gas treatment system by preparing the extraction passages 66 to transition to the desublimation stage 60. The coolant fluid 72 may include an inert gas, water, a refrigerant fluid, a cryogenic fluid, glycol mixtures, and / or or one or more additional fluids. For example, in some embodiments, the treated fluid stream 24 or the stream 78 of sublimated CO2 fluid (e.g., CO2 gas) may be used as the coolant fluid 72. In certain embodiments, the precooling stage 64 may continueIS24.1354-WO-PCT until the temperature of the extraction passages meets a threshold temperature and / or for a predetermined amount of time.

[0050] FIG. 3 is a phase diagram 100 of carbon dioxide under various phases, in accordance with aspects of the present disclosure. The phase diagram 100 illustrates variations between states of CO2 as related to pressures and temperatures. The phase diagram 100 includes a partial pressure of CO2 (e.g., atm.) versus temperature (°C). The phase diagram 100 illustrates a solid phase 102 of the CO2, a vapor phase 104 of the CO2. and a sublimation curve 106 at which the solid phase 102 and the vapor phase 104 may exist in equilibrium. As shown by a first arrow 108, the CO2 may transition from the solid phase 102 to the vapor phase 104 via sublimation (e.g., gasification or solid-to-gas conversion) based on a change in temperature. A second arrow 110 illustrates transition of the CCh from the vapor phase 104 via desublimation (e.g., deposition or gas-to-solid conversion) to the solid phase 102 based on a change in temperature. Additionally and / or alternatively, the CChmay transition from the solid phase 102 to the vapor phase 104 via sublimation based on a change in pressure, illustrated by a third arrow 112. A fourth arrow 114 illustrates transition of the CChfrom the vapor phase 104 to the solid phase 102 via desublimation based on a change in pressure. Thus, CO2 may transition between the solid phase 102 and the vapor phase 104 through changing the temperature alone, the pressure alone, or combination of the temperature and the pressure.

[0051] In some embodiments, the partial pressure of CO2 of the flue gas stream 18 provided to the gas treatment system 14 may vary due to the concentration of CO2 in the flue gas stream 18. The partial pressure of CCh may be based on processes used to generate the flue gas stream 18. For example, the flue gas stream 18 may be generated from various industrial processes, such as a chemical refinery, a combustion system, a reactor, cement plant, a coal plant, a natural gas plant, a manufacturing plant, a pharmaceutical plant, and the like. The phase diagram 100 illustrates various sources that may be used to generate the flue gas stream 18. The various sources may have different partial pressures of CO2. As shown, the various sources may include a cement plant source 116, a coal-fired power plant source 118, and a natural gas combined cycle (NGCC) power plant 120. The flue gas stream 18IS24.1354-WO-PCT from the cement plant source 116 may include a CCh mole percent of approximately 17% plus or minus 0.5, 1, 1.5, or 2%. In certain embodiments, the CO2 mole percent of the cement plant source 116 may range from 15% to 20%, 15% to 18%, or 15% to 17.7%. The flue gas stream 18 from the coal-fired power plant source 118 may include a CO2 mole percent of approximately 13% plus or minus 0.5, 1, 1.5, or 2%. The CChmole percent of the coal-fired power plant source 118 may range from 10% to 15%, 10% to 14%, or 10% to 13.1%. The flue gas stream 18 from the NGCC plant 120 may include a CO2 mole percent of approximately 4% plus or minus 0.5, 1, 1.5, or 2%. The CCh mole percent of the NGCC plant 120 may range from 2% to 6%, 3% to 5%, or 3.5% to 4.5%. It should be noted that the various sources illustrated in FIG. 3 are non-limiting and additional sources are envisioned to be treated by the gas treatment system 14.

[0052] FIG. 4 is a schematic of an embodiment of the gas treatment system 14 including a heat exchanger 28, a coolant subsystem 30, and a purge subsystem 32, in accordance with an embodiment of the present disclosure. In the following discussion, the gas treatment system 14 is described as capturing CO2 from the flue gas stream 18; however, the gas treatment system 14 described herein may be used to capture any undesirable gases (e.g., COx, NOx, SOx, etc.) from the flue gas stream 18. The heat exchanger 28 may include one or more extraction passages 66, one or more coolant passages 68, one or more treated fluid passages 150, or a combination thereof. The coolant subsystem 30 may include a refrigeration unit, a cryo-cooler, and / or one or more additional components that may be used to circulate the coolant fluid 72 (e.g., a coolant fluid stream 152) to the coolant passages 68 of the heat exchanger 28. The purge subsystem 32 may include a CO2 cylinder 154 (e.g., supply tank), a CO2 storage tank 156, a purge heat exchanger 158, a compressor 160, one or more manifold 162, or a combination thereof. The purge subsystem 32 may be used to remove a captured fluid stream 22 from the extraction passages 66 of the heat exchanger 28. In some embodiments, a controller 16 may be used to communicatively couple the heat exchanger 28, the coolant subsystem 30, the purge subsystem 32, one or more sensors 42, or a combination thereof. In some embodiments, the sensors 42 may generate feedback data to control a flow of one or more portions of the gas treatment system 14.IS24.1354-WO-PCT

[0053] In certain embodiments, a flue gas stream 18 may be provided to the gas treatment system 14 via an inlet flow path 164. The flue gas stream 18 may be provided to an inlet heat exchanger 166, a separator 168, a compressor 170, or a combination thereof. For example, the flue gas stream 18 may be pretreated by cooling of the flue gas stream 18 by the inlet heat exchanger 166. The cooled flue gas stream 18 may be further processed by the separator 168. The separator 168 may remove one or more components (e.g., liquids and / or solids) from the cooled flue gas stream 18. The separator 168 may include a centrifugal separator, a gravity separator, or a combination thereof. The one or more components may include water and / or water vapor. As such, the separator 168 may remove moisture from the cooled flue gas stream 18. Additionally and / or alternatively, the flue gas stream 18 may be compressed by the compressor 170. Compression of the flue gas stream 18 may be used to overcome one or more pressures drops within the heat exchanger 28. As such, the compressor 170 may compress the flue gas stream 18 to above atmospheric pressure. The flue gas stream 18 may be compressed to about 3 psig to 5 psig, 5 psig to 10 psig, about 10 psig to 15 psig, about 10 psig, and the like.

[0054] In some embodiments, the flue gas stream 18 maybe provided via the inlet flow path 164 to a first manifold 162, 172 of the heat exchanger 28. The first manifold 162, 172 may selectively connect one or more flow paths to the heat exchanger 28. That is, the flue gas stream 18 may enter the heat exchanger 28 via the inlet flow path 164 and / or one or more additional flow paths. The first manifold 162, 172 may include one or more valves (e.g., actuator controlled valves coupled to the controller 16). The valves may be controlled by the controller 16 to control a flow of the flue gas stream 18 into an inlet 174 of the extraction passages 66 of the heat exchanger 28. The actuator controlled valves may include one or more gate valves, ball valves, flapper valves, needle valves, butterfly valves, diaphragm valves, pinch valves, choke valves, or any combination thereof. The actuator controlled valves may include actuators (e.g., electric actuators, hydraulic actuators, or pneumatic actuators) configured to move the valves between open and closed positions in response to control by the controller 16. The actuator controlled valves may be controlled by the controller 16 based on a variety of sensor feedback from the sensors 42.IS24.1354-WO-PCT

[0055] The heat exchanger 28 may be a plate and fin heat exchanger, a tube and shell heat exchanger, or one or more additional types of heat exchangers. Flow of fluid through the extraction passages 66, the coolant passages 68, and / or the treated fluid passages 150 may include parallel flow, counter flow, cross flow, and the like. In some embodiments, the heat exchanger 28 may receive the flue gas stream 18 via the inlet flow path 164 at the inlet 174 of a first extraction passage 176 of the extraction passages 66. The first extraction passage 176 may be in a desublimation stage 60. As such, the coolant subsystem 30 may circulate the coolant fluid 72 (e.g., coolant fluid stream 152) into the coolant passage 68 to indirectly cool the first extraction passage 176. Indirect cooling of the first extraction passage 176 may be performed by the coolant subsystem 30 to reduce a temperature of the first extraction passage 176 below a deposition point. In this manner, the first extraction passage 176 may receive the flue gas stream 18 and form a solid CO2 deposit 70 or other solid deposit (e.g., COx, NOx, SOx, and / or water deposit). The first extraction passage 176 may continue to receive the flue gas stream 18 until a threshold loading capacity. The threshold loading capacity may be based on the amount of CChin the CO2 deposit 70 (or other amount in solid deposit if extracting COx, NOx, SOx, and / or water), a time in the desublimation stage 60, or a combination thereof.

[0056] In some embodiments, the first extraction passage 176 may output a fluid 178 (e.g., treated flue gas) into a second manifold 162, 186, which routes the fluid 178 into the treated fluid passage 150. The treated fluid passage 150 may output the treated fluid stream 24 via an outlet flow path 180. The treated fluid passage 150 may be indirectly cooled by the coolant subsystem 30 to improve operational efficiency of the heat exchanger 28 by limiting changes in temperature along the extraction passages 66 and / or the coolant passages 68. It should be noted, in some embodiments, the treated fluid passage 150 may be used to extract CO2 to form one or more additional CO2 deposits. The treated fluid stream 24 may be substantially free of CO2. Additionally and / or alternatively, the treated fluid stream 24 may be substantially free of NOXand / or SOXif extracting NOx and / or SOx. For example, substantially free of NOXand / or SOXmay be with concentrations less than 100 ppm each. In certain embodiments, the first extraction passage 176 is cooled to a first temperature while the treated fluid passage 150 is cooled to a second cooled temperature different from the firstIS24.1354-WO-PCT temperature, wherein the different temperatures can be used to sublimate different undesirable gases from the flue gas stream 18 in stages. In certain embodiments, the first extraction passage 176 and / or the treated fluid passage 150 may be configured to sublimate a combination of undesirable gases (i.e., combined solid deposits), which can later be separated during sublimation stages and / or gas separation techniques. Thus, while the present discussion uses CO2 as an example, the gas treatment system 14 may be controlled in a variety of ways to capture undesirable gases from the flue gas stream 18.

[0057] In certain embodiments, a temperature profile of the coolant passages 68 may be controlled by the controller 16. As such, the gas treatment system 14 may remove CChfrom flue gas streams in which the CO2 present in the flue gas streams differ. That is, the amount of indirect cooling of the first extraction passage 176 may be controlled via the controller 16 based on a CO2 content and / or a source of flue gas. Control of the temperature profile via the controller and the coolant subsystem 30 may increase an ability of the gas treatment system 14 to dynamically change based on the CO2 content of flue gas. The temperature profile of the coolant passages 68 may be controlled by the controller 16 in a similar manner for capture of any undesirable gases (e.g., COx, NOx, and / or SOx), various sources, and various contents of such undesirable gases.

[0058] In some embodiments, a second extraction passage 182 may operate in the sublimation stage 62. The second extraction passage 182 may include a CO2 deposit 70 that may be removed via the purge subsystem 32. As shown, the purge subsystem 32 may provide a purge fluid 76 to the second extraction passage 182 via a purge flow path 184 to sublimate the CO2 deposit 70. In some embodiments, the purge fluid 76 may be a CO2 containing fluid (e.g., gaseous CO2). In this manner, the purge fluid 76 may be provided from the CO2 cylinder 154. The purge fluid 76 may be heated by the purge heat exchanger 158 to a temperature greater than or equal to the sublimation point of the CO2 deposit 70. The heated purge fluid 76 may be compressed by the compressor 160 and provided to the second extraction passage 182 via the first manifold 162, 172. The heated purge fluid 76 may pass through the second extraction passage 182 and the CO2 deposit 70 may undergo sublimation. As such, the second extraction passage 182 may output a captured fluid stream 22 (e.g.,IS24.1354-WO-PCT captured gas stream including purge fluid and sublimated fluid) via the second manifold 162, 186. The captured fluid stream 22 may be output via a purge flow path 188 to the CO2 cylinder 154, the CO2 storage tank 156, or a combination thereof. The second extraction passage 182 may operate in the sublimation stage 62 until the CO2 deposit 70 is removed, for a set period of time, or a combination thereof.

[0059] In some embodiments, the first manifold 162, 172 and / or the second manifold 162, 186 may be used to transition the first extraction passage 176 and the second extraction passage 182 between various stages (e.g., desublimation stage 60, sublimation stage 62, precooling stage 64). As such, it should be noted that the first extraction passage 176 may be transitioned to the sublimation stage 62 when the threshold loading capacity is reached. The second extraction passage 182 may be transitioned to the desublimation stage 60 or the precooling stage 64 after the set period of time. In certain embodiments, each of the illustrated passages 66 and 68 may include a single passage or a plurality of passages (e.g., 2, 3, 4, 5, or more passages).

[0060] In certain embodiments, the controller 16 may control flows of the flue gas stream 18 and the purge fluid 76 alternatingly through the first and second extraction passages 176 and 182 of the heat exchanger 28 to alternate the first and second extraction passages 176 and 182 between operation in the desublimation stage 60 and the sublimation stage 62. For example, during a first duration of time, the controller 16 may control valves in the first and second manifold 162, 172, 186 to direct the flue gas through the first extraction passage 176 (e.g., desublimation stage 60) followed by the treated fluid passage 150, and to direct the purge fluid 76 through the second extraction passage 182 (e.g., sublimation stage 62). By further example, during a second duration of time, the controller 16 may control valves in the first and second manifold 162, 172, 186 to stop flow of the purge fluid 76 and direct only the flue gas through the second extraction passage 182 (e.g., desublimation stage 60) followed by the treated fluid passage 150, and to stop flow of the flue gas and direct only the purge fluid 76 through the first extraction passage 176 (e.g., sublimation stage 62). The controller 16 may continue alternating the fluid flows in subsequent durations of time.IS24.1354-WO-PCT

[0061] In certain embodiments, the controller 16 may control flows of the flue gas stream 18 and the purge fluid 76 alternatingly through the first and second extraction passages 176 and 182 of the heat exchanger 28 to alternate the first and second extraction passages 176 and 182 between operation in the desublimation stage 60, the sublimation stage 62, and the precooling stage 64. For example, during a first duration of time, the controller 16 may control valves in the first and second manifold 162, 172, 186 to direct only the flue gas through the first extraction passage 176 (e.g., desublimation stage 60) followed by the treated fluid passage 150, and to direct only the purge fluid 76 through the second extraction passage 182 (e g., sublimation stage 62). During a second duration of time, the controller 16 may control valves in the first and second manifold 162, 172, 186 to continue flow of the flue gas through the first extraction passage 176 (e.g., desublimation stage 60) followed by the treated fluid passage 150, to stop flow of the purge fluid 76 through the second extraction passage 182 (e.g., stop the sublimation stage 62). Additionally and / or alternatively, the controller 16 may during the second duration of time direct the coolant fluid (e.g., coolant fluid 72 or another coolant fluid) through one or more of the coolant passages 68 to indirectly cool the second extraction passage 182 (e.g., start the precooling stage 64). It should be noted, that the purge fluid 76 and the coolant fluid 72 do not mix. During a third duration of time, the controller 16 may control valves in the first and second manifold 162, 172, 186 to direct the flue gas through the second extraction passage 182 (e.g., desublimation stage 60) followed by the treated fluid passage 150, and to stop flow of the flue gas and direct only the purge fluid 76 through the first extraction passage 176 (e.g., sublimation stage 62). During the third duration of time, the controller may stop flow of the coolant fluid through the coolant passages 68. The controller 16 may continue alternating the fluid flows in subsequent durations of time.

[0062] FIG. 5 is a schematic of an embodiment of the gas treatment system 14 including a cryogenic cooler or cryo-cooler 250, in accordance with an embodiment of the present disclosure. The embodiment of FIG. 5 is substantially the same as described above with reference to FIG. 4, except that the embodiment of FIG. 5 includes the cryo-cooler 250 and additionally passages in the heat exchanger 28. The cryo-cooler may include an expander 252, a compressor 254, an aftercooler 256, or a combination thereof. The cryo-cooler 250IS24.1354-WO-PCT may be a portion of the coolant subsystem 30 and may be used to circulate the coolant fluid 72 (e.g., coolant fluid stream 152) to the coolant passages 68 of the heat exchanger 28. The cryo-cooler 250 may establish a closed loop to enable recycling of the coolant fluid 72 during operation of the gas treatment system 14.

[0063] In some embodiments, the coolant fluid 72 may be provided to a first coolant passage 258 of the coolant passages 68 of the heat exchanger 28. The coolant fluid 72 may be cooled via the expander 252. For example, the expander 252 may include a turboexpander that may cool the coolant fluid 72 by expanding the coolant fluid 72 to induce a temperature drop. The coolant fluid may be provided to the first coolant passage 258 via the coolant fluid stream 152. The coolant fluid stream 152 may be output via a coolant manifold 260. The coolant manifold 260 may control the flow of the coolant fluid 72 to the compressor 254. The compressor 254 may compress the coolant fluid 72 and provide the coolant fluid to the aftercooler 256. The aftercooler 256 may include a heat exchanger, a moisture separator, a mechanical cooling unit, and the like. The cryo-cooler 250 may provide the coolant fluid 72 via an aftercooled path 262 to the coolant manifold 260. The coolant manifold 260 may direct the coolant fluid 72 to a second coolant passage 264. The second coolant passage 264 may direct the coolant fluid 72 to the expander 252 via an outlet 266 for further cooling. The cryo-cooler 250 may continuously cycle the coolant fluid 72 between the coolant passages 68 to indirectly cool the extraction passages 66 and / or the one or more treated fluid passages 150 of the heat exchanger 28. The coolant fluid 72 may be an inert gas, such as a noble gas (e.g., argon, helium, neon, etc.), nitrogen, CO2, or any combination thereof. For purposes of illustration, the present discussion refers to nitrogen as the coolant fluid 72. However, other coolant fluids 72 are within the scope of the illustrated embodiment. As such, the expander 252 may be a nitrogen expander, ft should be noted, the coolant fluid 72 may be one or more additional fluids=.

[0064] In some embodiments, the heat exchanger 28 may include a first extraction passage 268, a second extraction passage 270, and a third extraction passage 272. A first manifold 162, 274 and a second manifold 162, 276 may be used to control fluid flow between the extraction passages 66 and transition between various stages (e.g., the desublimation stageIS24.1354-WO-PCT60, the sublimation stage 62, and / or the precooling stage 64). As shown, the first extraction passage 268 may operate in the precooling stage 64, the second extraction passage 270 may operate in the sublimation stage 62, and the third extraction passage 272 may operate in the desublimation stage 60. Subsequently, the second extraction passage 270 may operate in the precooling stage 64, the third extraction passage 272 may operate in the sublimation stage 62, and the first extraction passage 268 may operate in the desublimation stage 60. Subsequently, the third extraction passage 272 may operate in the precooling stage 64, the first extraction passage 268 may operate in the sublimation stage 62, and the second extraction passage 270 may operate in the desublimation stage 60. Thus, each cycle of the heat exchanger 28 transitions one or more extraction passages (e.g., 268, 270, 272) in a sequence of the precooling stage 64, the sublimation stage 62, and the desublimation stage 60. The controller 16 controls valves in the manifolds (e.g., 162, 274, 276) to transition between the coolant fluid 72, the flue gas stream 18, and the purge fluid 76 when transitioning the one or more extraction passages (e.g., 268, 270, 272) between the different stages (e.g., 64, 62, and 60). The purge subsystem 32 may operate as described in reference to FIG. 4. It should be noted, the gas treatment system 14 may include one or more additional extraction passage and / or one or more additional coolant passages. In this manner, the heat exchanger 28 may operate various extraction passages in similar stages in parallel.

[0065] FIG. 6 is a schematic of an embodiment of the gas treatment system 14 including a cryo-cooler 250 and a purge subsystem 32 including a pump 300. The cryo-cooler 250 is substantially the same as discussed above in the embodiment of FIG. 5. The pump 300 may be a cryo-pump or a vacuum pump. In some embodiments, operation of the sublimation stage 62 may remove the CO2 deposit 70 from a first extraction passage 302 of the extraction passages 66. The purge subsystem 32 may provide a purge fluid 76 to the first extraction passage 302 via a purge flow path 184. The purge fluid 76 may extract the CO2 deposit 70 through sublimation and output a captured fluid stream 22 via a manifold 162, 304. The captured fluid stream 22 may be provided to the pump 300. The pump 300 may be a cryo- pump and may be used to remove gases and / or vapors from the captured fluid stream 22. The captured fluid stream 22 may be stored in a CO2 storage tank 156.IS24.1354-WO-PCT

[0066] In some embodiments, the purge subsystem 32 may use a change in pressure to remove the CO2 deposit 70 from the extraction passages 66. For example, the CO2 deposit 70 may be removed from the first extraction passage 302 using the pump 300 (e.g., a vacuum pump). The vacuum pump (e.g., pump 300) may suction the CO2 deposit 70 from the first extraction passage 302. The vacuum pump may cause the CO2 deposit 70 to sublimate causing a phase transition as indicated by the third arrow 112 in FIG. 3. In this embodiment, the purge subsystem 32 may not provide the purge fluid 76 to the first extraction passage 302. That is, the pump 300 may remove the CO2 deposit 70 directly from the first extraction passage 302 via a change in pressure.

[0067] In certain embodiments, the gas treatment system 14 may operate a second extraction passage 306 in the desublimation stage 60 in substantially the same manner as discussed in detail above with reference to FIGS. 4 and 5. As such, the flue gas stream 18 may be provided to the manifold 162, 303 and introduced to the second extraction passage 306 to generate the CO2 deposit 70. The treated fluid stream 24 may be output from the treated fluid passage 150 for further use. The heat exchanger 28 may include various coolant passages 68 such as the first coolant passage 258 and the second coolant passage 264 as described in reference to FIG. 6.

[0068] In certain embodiments, the controller 16 may control flows of the flue gas stream 18 and the purge fluid 76 alternatingly through the first and second extraction passages 302 and 306 of the heat exchanger 28 to alternate the first and second extraction passages 302 and 306 between operation in the desublimation stage 60 and the sublimation stage 62. For example, during a first duration of time, the controller 16 may control valves in the first and second manifold 162, 303, 304 to direct the flue gas through the second extraction passage 306 (e.g., desublimation stage 60) followed by the treated fluid passage 150, and to direct the purge fluid 76 through the first extraction passage 302 (e.g., sublimation stage 62). By further example, during a second duration of time, the controller 16 may control valves in the first and second manifold 162, 303, 304 to stop flow of the purge fluid 76 and direct only the flue gas through the first extraction passage 302 (e.g., desublimation stage 60) followed by the treated fluid passage 150, and to stop flow of the flue gas and direct only the purge fluid 76IS24.1354-WO-PCT through the second extraction passage 306 (e.g., sublimation stage 62). The controller 16 may continue alternating the fluid flows in subsequent durations of time.

[0069] In certain embodiments, the controller 16 may control flows of the flue gas stream 18 and the purge fluid 76 alternatingly through the first and second extraction passages 302 and 306 of the heat exchanger 28 to alternate the first and second extraction passages 302 and 306 between operation in the desublimation stage 60, the sublimation stage 62, and the precooling stage 64. For example, during a first duration of time, the controller 16 may control valves in the first and second manifold 162, 303, 304 to direct only the flue gas through the second extraction passage 306 (e.g., desublimation stage 60) followed by the treated fluid passage 150, and to direct only the purge fluid 76 through the first extraction passage 302 (e.g., sublimation stage 62). During a second duration of time, the controller 16 may control valves in the first and second manifold 162, 303, 304 to continue flow of the flue gas through the second extraction passage 306 (e.g., desublimation stage 60) followed by the treated fluid passage 150, to stop flow of the purge fluid 76 through the first extraction passage 302 (e.g., stop the sublimation stage 62). Additionally and / or alternatively, the controller 16 may control valves in the coolant manifold 260 during the second duration of time to direct the coolant fluid (e.g., coolant fluid 72 or another coolant fluid) through the first coolant passage 258 of the coolant passages 68 of the heat exchanger 28 to indirectly cool the first extraction passage 302 (e.g., start the precooling stage 64). It should be noted, that the purge fluid 76 and the coolant fluid 72 do not mix. During a third duration of time, the controller 16 may control valves in the first and second manifold 162, 303, 304 to direct the flue gas through the first extraction passage 302 (e.g., desublimation stage 60) followed by the treated fluid passage 150, and to stop flow of the flue gas and direct only the purge fluid 76 through the second extraction passage 306 (e.g., sublimation stage 62). The controller 16 may continue alternating the fluid flows in subsequent durations of time.

[0070] FIG. 7 is a flow chart of a process 400 for operating a gas treatment system 14 to capture CO2 (or any other undesirable gas) in accordance with an embodiment of the present disclosure. The process 400 may be performed by a computing device or controller disclosed above with reference to FIG. 1 or any other suitable computing device(s) or controller(s).IS24.1354-WO-PCTFurthermore, the blocks of the process 400 may be performed in the order disclosed herein or in any suitable order. For example, certain blocks of the process 400 may be performed concurrently. In addition, in certain embodiments, at least one of the blocks of the process 400 may be omitted. The process 400 may include any or all of the features discussed in detail above with reference to FIGS. 1-6.

[0071] At block 402 of the process 400, the gas treatment system 14 may supply a coolant fluid 72 to a heat exchanger 28 having a plurality of passages. The heat exchanger 28 may include passages, such as the extraction passages 66, the coolant passages 68, the treated fluid passages 150, and the like. At block 404 of the process 400, the gas treatment system 14 may deposit carbon dioxide from a flue gas stream 18 into a CO2 deposit 70 in one or more of the plurality of passages (e.g., extraction passages 66) cooled by the coolant fluid during a desublimation stage 60. The extraction passages 66 may be cooled by the coolant fluid 72 provided by a coolant subsystem 30 of the gas treatment system 14. The coolant fluid 72 may be provided to the coolant passages 68 of the heat exchanger 28, wherein the coolant passages 68 are independent and fluidly isolated from the extraction passages 66. As such, the coolant passages 68 may indirectly cool the extraction passages 66, thereby causing the CO2 deposit 70 to form within the extraction passages 66.

[0072] At block 406 of the process 400, the gas treatment system 14 may extract the CO2 deposit 70 from the one of the plurality of passages into a CO2 fluid during a sublimation stage 62. The purge subsystem 32 of the gas treatment system 14 may provide a purge fluid 76 to the extraction passages 66 of the heat exchanger 28 to sublimate the CO2 deposit 70. The purge fluid 76 may be at a temperature above the sublimation point of the CO2 deposit 70. As such, the purge fluid 76 may mix with the CO2 fluid and generate a captured fluid stream 22 (e.g., a combination of the CO2 deposit 70 and the purge fluid 76).

[0073] At block 408 of the process 400, the gas treatment system 14 may capture the CO2 fluid in a storage container. For example, the CO2 fluid and / or the captured fluid stream 22 may be stored in a CO2 storage tank. In some embodiments, a portion of the captured fluid stream 22 may be recycled and used as the purge fluid 76 for subsequent operation of the sublimation stage 62. At block 410 of the process 400, the gas treatment system 14 mayIS24.1354-WO-PCT monitor one or more parameters of the desublimation stage 60 and the sublimation stage 62. The parameters may include a loading percentage of the extraction passages 66 during operation of the desublimation stage 60. Additionally and / or alternatively the parameters may include an operational time (e.g., cycle time or stage time) of the desublimation stage 60 and / or the sublimation stage 62. For example, an operational time may be established for the desublimation stage 60 and / or the sublimation stage 62 during start up and / or upon a change of the source of the flue gas stream 18. In some embodiments, the parameters may include one or more of a flow rate through the passage, a pressure drop across the passage, a measured concentration of the captured gas at an outlet of the passage, and a temperature at an outlet of the passage. In this manner, the parameters may be established for operation at one or more partial pressures of CO2.

[0074] At block 412 of the process 400, the gas treatment system 14 may compare the one or more parameters to one or more thresholds to obtain a comparison. The one or more thresholds may include a loading capacity of the extraction passages 66, one or more predetermined operational times, or a combination thereof. At block 414 of the process 400, the gas treatment system 14 may switch the plurality of passages between the desublimation stage 60 and the sublimation stage 62 based on the comparison. For example, the extraction passages 66 may transition from the desublimation stage 60 to the sublimation stage 62 based on the comparison of the loading percentage and the loading capacity of the extraction passage. Additionally and / or alternatively, the extraction passages 66 may transition from the desublimation stage 60 to the sublimation stage 62 based on the comparison of the current operational time and the predetermined operational time of the extraction passage. The gas treatment system 14 may transition the extraction passages 66 from the sublimation stage 62 to the desublimation stage 60 based on the comparison of the operational time of the purge subsystem 32 and the predetermined operation time.

[0075] FIG. 8 is a flow chart of a process 500 for operating a gas treatment system 14 to capture carbon dioxide and storing the captured carbon dioxide, in accordance with an embodiment of the present disclosure. The process 500 may be performed by a computing device or controller disclosed above with reference to FIG. 2 and FIG. 6 or any other suitableIS24.1354-WO-PCT computing device(s) or control ler(s). Furthermore, the blocks of the process 500 may be performed in the order disclosed herein or in any suitable order. For example, certain blocks of the process 500 may be performed concurrently. In addition, in certain embodiments, at least one of the blocks of the process 500 may be omitted. The process 500 may include any or all of the features discussed in detail above with reference to FIGS. 1-6.

[0076] At block 502 of the process 500, the gas treatment system 14 may precool an extraction passage 66 of a heat exchanger 28. The gas treatment system 14 may precool the extraction passage 66 in a precooling stage 64. A coolant subsystem 30 of the gas treatment system 14 may indirectly cool the extraction passage 66. Indirect cooling may be performed by flowing a coolant fluid 72 through one or more coolant passages 68. The coolant passages 68 may be positioned proximate to, but independent and fluidly isolated from, the extraction passage 66. The coolant fluid may be cooled via a turboexpander and / or a refrigerator unit. In some embodiments, the coolant fluid may include an inert gas, such as a noble gas (e.g., argon, helium, neon, etc.), nitrogen, CO2, or any combination thereof. For example, for purposes of discussion, the coolant fluid 72 may include nitrogen. The coolant fluid 72 may be approximately -140°C. That is, the coolant subsystem 30 may cool nitrogen to approximately -140°C to enable indirect cooling of the extraction passage 66 to below the desublimation point of CO2. The precooling stage 64 may precool the extraction passage 66 for a set period of time. Additionally and / or alternatively, the precooling stage 64 may cool the extraction passage 66 to a predetermined temperature. For example, in certain embodiments, the precooling stage 64 may precool the extraction passage 66 by about 30°C to 100°C, about 50°C to 65°C, about 30°C to 50°C, and the like. In some embodiments, precooling the extraction passage 66 may be advantageous to reduce operational costs and improve energy efficiency of the gas treatment system 14.

[0077] At block 504 of the process 500, the gas treatment system 14 may receive a flue gas stream 18 having carbon dioxide at the cooled extraction passage 66. The flue gas stream 18 may originate from various sources. For example, the flue gas stream 18 may originate from a NGCC plant. The NGCC power plant may produce a flue gas stream with a CO2 mole percent of 4.5% at 1 bar and 165°C. In the desublimation stage 60, the flue gas stream 18IS24.1354-WO-PCT from the NGCC power plant may be provided to the cooled extraction passage 66. The cooled extraction passage 66 may be indirectly cooled via the coolant passage 68 to a temperature based on the CO2 partial pressure. With this in mind, it should be noted, the flue gas stream 18 may originate from a source with a higher CO2 partial pressure, such as flue gas originating from a coal-fired power plant. In this manner, the temperature profile of the extraction passage may be varied to increase an efficiency of the gas treatment system 14.

[0078] At block 506 of the process 500, the gas treatment system 14 may deposit carbon dioxide from the flue gas stream 18 in the cooled extraction passage 66. The CChmay form a CO2 deposit 70 on one or more walls of the cooled extraction passage 66. The amount of buildup on an interior of the cooled extraction passage 66 may be based on the CO2 partial pressure, the temperature profile of the extraction passage 66, a loading percentage of the extraction passage 66, or a combination thereof. At block 508 of the process 500, the gas treatment system 14 may monitor a parameter indicative of a buildup of the deposited carbon dioxide in the cooled extraction passage 66. The parameter indicative of the buildup of the deposited carbon (e.g., the CO2 deposit 70) may include the loading percentage of the extraction passage 66, a decrease in CO2 removal from the flue gas stream 18, a period of time, and the like. In some embodiments, the parameters may include one or more of a flow rate through the extraction passage 66, a pressure drop across the extraction passage 66, a measured concentration of the captured gas at an outlet of the extraction passage 66, and a temperature at an outlet of the extraction passage 66. At block 510 of the process 500, the gas treatment system 14 may compare the parameter against a threshold. The threshold may include a loading capacity of the extraction column, a percentage of CO2 remaining in the treated fluid stream 24, a set period of time, and the like.

[0079] At block 512 of the process 500, the gas treatment system 14 may determine if the parameter meets the threshold. In some embodiments, the parameter may not meet the threshold and the gas treatment system 14 may return to block 508. In other embodiments, the parameter may meet the threshold and the gas treatment system 14 may proceed to block 514. At block 514 of the process 500, the gas treatment system 14 may extract carbon dioxide from the extraction passage 66 of the heat exchanger 28. Removal of the CO2 from theIS24.1354-WO-PCT extraction passage 66 may be performed by a purge subsystem 32 of the gas treatment system 14. In some embodiments, the purge subsystem 32 may remove the CChby flowing a purge fluid 76 through the extraction passage 66 in the sublimation stage 62. In this manner, the purge fluid may increase a temperature of the extraction passage 66 above the sublimation point and generate a captured fluid containing the CO2 from the CO2 deposit 70. In other embodiments, the purge subsystem 32 may generate a change in pressure using a vacuum pump and cause sublimation of the CO2 from the extraction passage 66 as a function of pressure.

[0080] At block 516 of the process 500, the gas treatment system 14 may store the extracted carbon dioxide. The extracted CO2 may be stored in a storage tank for future use in one or more applications. The stored CO2 may be used stored in geological reservoirs or may be further purified for use in medical and / or food products. In some embodiments, a portion of the extracted CO2 may be used as the purge fluid 76. In this way, the purge subsystem 32 may recycle the portion of the CChto extract additional CChfrom one or more additional extraction passages. Returning to the example of treating the flue gas stream 18 generated from the NGCC power plant, the gas treatment system 14 may recover between approximately 85 to 99 percent, between approximately 90 to 99 percent, or between approximately 95 to 99 percent of CO2 from the flue gas stream 18. It should be noted, in some instances the gas treatment system 14 may recover a percentage of CO2 based on a design of process parameters of a source of the flue gas stream 18 and / or the gas treatment system 14. As such, indirectly cooling the extraction passage 66 to extract CChfrom the flue gas stream 18 may produce a treated gas substantially free of CO2.

[0081] Technical effects of the disclosed embodiments include a gas treatment system 14 to capture CChfrom by indirectly cooling passages of a heat exchanger to extract CO2. The gas treatment system 14 may include one or more heat exchangers, a coolant subsystem, a purge subsystem, or a combination thereof. The gas treatment system may be used to control desublimation (e.g., extraction) and sublimation of CO2 from a flue gas stream provided from various sources. In certain embodiments, the gas treatment system 14 may be used to indirectly cool the one or more extraction passages of the heat exchanger. Advantageously,IS24.1354-WO-PCT by indirectly cooling the one or more extraction passage, the gas treatment system 14 may reduce contamination of a coolant fluid and / or a treated fluid stream. For example, the gas treatment system 14 may have a closed loop solution from cooling one or more coolant passages of the heat exchanger 28 used to indirectly cool the extraction passages. In this manner, start-up and shut-down of the gas treatment system 14 may be streamlined. A controller 16 of the gas treatment system 14 may receive sensor feedback from one or more sensors 42 and analyze one or more parameters (e.g., periods of time, valve set points, valve positions, temperature, pressure, flow rate, etc.) to determine procedures to improve operation of the gas treatment system 14. The disclosed techniques may provide control of a temperature profile of the cooled passages to improve efficiency of CO2 extraction. As such, deployment of the presently disclosed techniques may provide improved efficiency and performance of CO2 extraction through indirect cooling of passages of the heat exchanger.

[0082] The subject matter described in detail above may be defined by one or more clauses, as set forth below.

[0083] A system is provided that includes a carbon capture system. The carbon capture system may include a heat exchanger including a plurality of passages, a coolant subsystem coupled to the heat exchanger, wherein the coolant subsystem is configured to indirectly cool and deposit carbon dioxide (CO2) from a flue gas stream into a CO2 deposit within a first subset of the plurality of passages during a desublimation stage, wherein the coolant fluid is configured to circulate a coolant fluid different than the flue gas stream. The carbon capture system also includes a purge subsystem coupled to the heat exchanger, wherein the purge subsystem is configured to sublimate and purge the CO2 deposit from the first subset of the plurality of passages during a sublimation stage.

[0084] The system of the preceding clause, wherein the coolant subsystem is configured to circulate the coolant fluid through a second subset of the plurality of passages, and the first and second subsets are different from one another.

[0085] The system of any of the preceding clauses, wherein the coolant subsystem is a closed loop.IS24.1354-WO-PCT

[0086] The system of any of the preceding clauses, wherein the coolant fluid is substantially free of moisture and CO2.

[0087] The system of any of the preceding clauses, wherein the coolant subsystem is configured to pre-cool the first subset of the plurality of passages during a pre-cooling stage before the desublimation stage and after the sublimation stage.

[0088] The system of any of the preceding clauses, wherein the coolant subsystem includes a cryogenic coolant subsystem having the coolant fluid.

[0089] The system of any of the preceding clauses, wherein the coolant fluid of the cryogenic coolant subsystem includes an inert gas.

[0090] The system of any of the preceding clauses, wherein the cryogenic coolant subsystem includes a cryo-cooler, an expander, a compressor, and an aftercooler.

[0091] The system of any of the preceding clauses, wherein the coolant subsystem includes a refrigeration subsystem.

[0092] The system of any of the preceding clauses, wherein the purge subsystem is configured to sublimate and purge the CO2 deposit from the first subset of the plurality of passages via a temperature differential, a pressure differential, or a combination thereof.

[0093] The system of the preceding clause, wherein the purge subsystem includes a compressor, a pump, a heater, or a combination thereof.

[0094] The system of any of the preceding clauses, wherein the purge subsystem includes a purge supply line extending between a purge source and the first subset of the plurality of passages, and the purge supply line includes a compressor configured to compress a purge fluid from the purge source.

[0095] The system of the preceding clause, wherein the purge subsystem imcludes a purge return line extending between the purge source and the first subset of the plurality of passages.IS24.1354-WO-PCT

[0096] The system of any of the preceding clauses, wherein the purge subsystem includes a CO2 storage, a cryogenic pump, a purge supply line extending between the first subset of the plurality of passages and the CO2 storage, wherein the purge supply line is configured to supply a purge fluid into the first subset of the plurality of passages, and a purge return line extending between the first subset of the plurality of passages and the CO2 storage, and the purge return line is configured to return the purge fluid and the CO2 deposit to the CO2 storage.

[0097] The system of any of the preceding clauses, wherein the purge subsystem includes a purge line extending between the first subset of the plurality of passages and a CO2 storage, and the purge line includes a vacuum pump.

[0098] A method is provided that includes indirectly cooling, via a coolant subsystem including a coolant fluid, a first subset of a plurality of passages of a heat exchanger during a desublimation stage, flowing a flue gas stream through the first subset of the plurality of passages during the desublimation stage, wherein the flue gas stream is different thant the coolant fluid. The method also includes depositing a carbon dioxide (CO2) deposit from the flue gas stream in the first subset of the plurality of passages during the desublimation stage, and sublimating and purging the CO2 deposit from the first subset of the plurality of passages during a sublimation stage.

[0099] The method of the preceding clause, including circulating the coolant fluid through a second subset of the plurality of passages, wherein the first and second subsets of the plurality of passages are different from one another.

[0100] The method of the preceding clause, including pre-cooling the first subset of the plurality of passages during a pre-cooling stage before the desublimation stage and after the sublimation stage.

[0101] The method of any of the preceding clauses, including transitioning from the desublimation stage to the sublimation stage based a comparison of one or more parameters and one or more thresholds, wherein the one or more parameters includes at least one of aIS24.1354-WO-PCT loading percentage, a flow rate, a pressure drop, a measured concentration, or a temperature, and wherein the threshold includes at least one of an operational time or a loading capacity.

[0102] A gas treatment system is provided that includes a carbon capture system. The carbon capture system include a heat exchanger including a plurality of passages, a coolant subsystem coupled to the heat exchanger, wherein the coolant subsystem is configured to indirectly cool and deposit carbon dioxide (CO2) from a flue gas stream into a CO2 deposit within a first subset of the plurality of passages during a desublimation stage, and wherein the coolant subsystem is a closed loop, wherein the coolant subsystem is configured to circulate a coolant fluid through a second subset of the plurality of passages, wherein the first and second subsets of the plurality of passages are different from one another, and wherein the coolant fluid is different than the flue gas stream. The carbon capture system also includes a purge subsystem coupled to the heat exchanger, wherein the purge subsystem is configured to sublimate and purge the CO2 deposit from the first subset of the plurality of passages during a sublimation stage.

[0103] The foregoing description, for purpose of explanation, has been described with reference to specific embodiments. However, the illustrative discussions above are not intended to be exhaustive or to limit the disclosure to the precise forms disclosed. Many modifications and variations are possible in view of the above teachings. Moreover, the order in which the elements of the methods described herein are illustrated and described may be re-arranged, and / or two or more elements may occur simultaneously. The embodiments were chosen and described in order to best explain the principals of the disclosure and its practical applications, to thereby enable others skilled in the art to best utilize the disclosure and various embodiments with various modifications as are suited to the particular use contemplated.

[0104] Finally, the techniques presented and claimed herein are referenced and applied to material objects and concrete examples of a practical nature that demonstrably improve the present technical field and, as such, are not abstract, intangible or purely theoretical. Further, if any claims appended to the end of this specification contain one or more elements designated as “means for [perform]ing [a function]...” or “step for [perform]ing [aIS24.1354-WO-PCT function], . it is intended that such elements are to be interpreted under 35 U.S.C. 112(f). However, for any claims containing elements designated in any other manner, it is intended that such elements are not to be interpreted under 35 U.S.C. 112(f).

Claims

IS24.1354-WO-PCTCLAIMS1. A system, comprising: a carbon capture system, comprising: a heat exchanger comprising a plurality of passages; a coolant subsystem coupled to the heat exchanger, wherein the coolant subsystem comprises a coolant fluid configured to indirectly cool and deposit carbon dioxide (CO2) from a flue gas stream into a CO2 deposit within a first subset of the plurality of passages during a desublimation stage, wherein the coolant fluid is configured to circulate a coolant fluid different than the flue gas stream; and a purge subsystem coupled to the heat exchanger, wherein the purge subsystem is configured to sublimate and purge the CO2 deposit from the first subset of the plurality of passages during a sublimation stage.

2. The system of claim 1, wherein the coolant subsystem is configured to circulate the coolant fluid through a second subset of the plurality of passages, and the first and second subsets are different from one another.

3. The system of claim 2, wherein the coolant subsystem is a closed loop.

4. The system of claim 2, wherein the coolant fluid is substantially free of moisture and CO2.

5. The system of claim 1, wherein the coolant subsystem is configured to pre-cool the first subset of the plurality of passages during a pre-cooling stage before the desublimation stage and after the sublimation stage.

6. The system of claim 1, wherein the coolant subsystem comprises a cryogenic coolant subsystem having the coolant fluid, the coolant fluid comprises an inert gas, and the cryogenic coolant subsystem comprises a cryo-cooler, an expander, a compressor, and an aftercooler.IS24.1354-WO-PCT7. The system of claim 1, wherein the coolant subsystem comprises a refrigeration subsystem.

8. The system of claim 1, wherein the purge subsystem is configured to sublimate and purge the CO2 deposit from the first subset of the plurality of passages via a temperature differential, a pressure differential, or a combination thereof.

9. The system of claim 1, wherein the purge subsystem comprises a purge supply line extending between a purge source and the first subset of the plurality of passages, the purge supply line comprises a compressor configured to compress a purge fluid from the purge source, and the purge subsystem comprises a purge return line extending between the purge source and the first subset of the plurality of passages.

10. The system of claim 1, wherein the purge subsystem comprises: a CO2 storage; a cryogenic pump; a purge supply line extending between the first subset of the plurality of passages and the CO2 storage, wherein the purge supply line is configured to supply a purge fluid into the first subset of the plurality of passages; and a purge return line extending between the first subset of the plurality of passages and the CO2 storage, and the purge return line is configured to return the purge fluid and the CO2 deposit to the CO2 storage.

11. The system of claim 1, wherein the purge subsystem comprises a purge line extending between the first subset of the plurality of passages and a CO2 storage, and the purge line comprises a vacuum pump.IS24.1354-WO-PCT12. A method, comprising: indirectly cooling, via a coolant subsystem comprising a coolant fluid, a first subset of a plurality of passages of a heat exchanger during a desublimation stage; flowing a flue gas stream through the first subset of the plurality of passages during the desublimation stage, wherein the flue gas stream is different than the coolant fluid; depositing a carbon dioxide (CO2) deposit from the flue gas stream in the first subset of the plurality of passages during the desublimation stage; and sublimating and purging the CO2 deposit from the first subset of the plurality of passages during a sublimation stage.

13. The method of claim 12, comprising: circulating the coolant fluid through a second subset of the plurality of passages, wherein the first and second subsets of the plurality of passages are different from one another.

14. The method of claim 13, comprising: pre-cooling the first subset of the plurality of passages during a pre-cooling stage before the desublimation stage and after the sublimation stage.

15. The method of claim 12, comprising: transitioning from the desublimation stage to the sublimation stage based a comparison of one or more parameters and one or more thresholds, wherein the one or more parameters comprises at least one of a loading percentage, a flow rate, a pressure drop, a measured concentration, or a temperature, and wherein the threshold comprises at least one of an operational time or a loading capacity.

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