Devices, systems, equipment and processes for optimizing carbon capture in industrial facilities

Abstract

Disclosed herein are devices, systems and methods for carbon capture optimization in industrial facilities. An exemplary carbon capture process includes cooling a flue gas stream using at least one gas-to-air heat exchanger located upstream of a carbon dioxide (CO2) absorber. Another exemplary carbon capture process includes heating a heat transfer medium for solvent regeneration and CO2 stripping using a combustion heater and / or using at least one waste heat recovery unit.

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to and the benefit of U.S. patent application Ser. No. 17 / 556,332, entitled "DEVICES, SYSTEMS, FACILITIES AND PROCESSES FOR CARBON CAPTURE OPTIMIZATION IN INDUSTRIAL FACILITIES BACKGROUND," filed Dec. 20, 2021, which is incorporated by reference in its entirety. The technology disclosed in this application relates to devices, systems, facilities and processes for carbon capture optimization in industrial facilities. [Background technology]

[0002] Industrial facilities that utilize combusted fuels can generate greenhouse gases, which include a variety of gaseous compounds, such as carbon dioxide, methane, nitrous oxide, hydrofluorocarbons, perfluorocarbons, and sulfur hexafluoride, that absorb radiation, trap heat in the atmosphere, and / or otherwise contribute to the undesirable environmental greenhouse effect. Summary of the Invention [Problem to be solved by the invention]

[0003] Carbon capture processes can be used to remove and / or reduce greenhouse gas emissions. There are several challenges associated with conventional implementations of post-combustion carbon capture processes in industrial facilities. One challenge involves the parasitic power load that can adversely affect the output and efficiency of industrial facilities that use carbon capture processes. Another challenge involves the additional cooling water load traditionally used in carbon capture systems and the environmental impacts associated with the use of such additional cooling water. To enable efficient absorption of carbon dioxide from the flue gas and reduce degradation of the absorption medium, conventional carbon capture processes typically use evaporative cooling water systems to cool the carbon dioxide-rich flue gas. Cooling water systems can be costly as they typically require makeup fresh water flows to replenish their cooling water loops, thus creating large demands on utilities and fresh water sources. [Means for solving the problem]

[0004] The present disclosure provides new and improved carbon capture systems, devices, equipment, and methods. In one example, a method for treating a flue gas stream includes cooling the flue gas stream using at least one gas-to-air heat exchanger disposed upstream of and in fluid communication with a carbon dioxide (CO2) absorber. The method also includes moving the flue gas stream through the gas-to-air heat exchanger and the CO2 absorber with a flue gas blower. The method also includes moving air through the gas-to-air heat exchanger with a cooled air blower to cool the flue gas stream.

[0005] In one example, a method for treating a flue gas stream includes receiving a rich solvent flowing from a carbon dioxide (CO2) absorber in a solvent regenerator. The rich solvent includes CO2 captured from the flue gas stream in the CO2 absorber. The method can also include heating a heat transfer medium using at least a combustion heater, where no additional heat is available at the host facility. The method also includes conveying the heated heat transfer medium from the combustion heater to the solvent regenerator. The method also includes generating combustion heater flue gas by the combustion heater. The method also includes conveying the combustion heater flue gas into the flue gas stream at a location upstream of the CO2 absorber.

[0006] In one example, a method for treating a flue gas stream includes a gas-to-air heat exchanger disposed upstream of and in fluid communication with a carbon dioxide (CO2) absorber. The gas-to-air heat exchanger receives and cools the flue gas stream. The gas-to-air heat exchanger conveys the cooled flue gas stream through the gas-to-air heat exchanger to and from the CO2 absorber. The system also includes a flue gas blower for moving the flue gas stream through the gas-to-air heat exchanger and the CO2 absorber. The system also includes a cooled air blower for moving air through the gas-to-air heat exchanger to cool the flue gas stream.

[0007] In one example, a system for treating a flue gas stream includes a carbon dioxide (CO2) absorber for receiving the flue gas stream. The system also includes a solvent regenerator in fluid communication with the CO2 absorber. The solvent regenerator receives a rich solvent from the CO2 absorber and provides a lean solvent to the CO2 absorber. The lean solvent has a lower amount of CO2 than the rich solvent. The systems may also include a combustion heater in fluid communication with the solvent generator and may not utilize additional waste heat from a host facility. The combustion heater heats and conveys a heat transfer medium toward the solvent regenerator. The combustion heater generates a combustion heater flue gas and conveys the combustion heater flue gas from the combustion heater for combination with the flue gas stream at a location upstream of the CO2 absorber.

[0008] Further examples, features and advantages of the disclosed devices, systems, equipment and methods are described in and will be apparent from the following detailed description and drawings. The features and advantages described herein are not all-inclusive, and many additional features and advantages will be apparent to those skilled in the art, particularly in view of the figures and descriptions. Also, a particular embodiment may not necessarily have all of the advantages enumerated herein. Furthermore, it should be noted that the language used herein has been selected primarily for ease of reading and explanation purposes, and is not intended to limit the scope of the inventive subject matter. The present disclosure will be described and explained with additional specificity and detail using the accompanying figures, with the understanding that the figures depict certain example embodiments and should not be considered as limiting the scope of the disclosure. [Brief description of the drawings]

[0009] [Figure 1] 1 is a schematic diagram of an exemplary carbon capture facility including a cooling device and a heating device according to an exemplary embodiment.

[0010] [Diagram 2] FIG. 2 is a schematic diagram of a first exemplary cooling device including a gas-to-air heat exchanger for cooling a flue gas stream in a carbon capture process according to an exemplary embodiment.

[0011] [Diagram 3] FIG. 2 is a schematic diagram of a second exemplary cooling apparatus including multiple gas-to-air heat exchangers for cooling a flue gas stream in a carbon capture process according to an exemplary embodiment.

[0012] [Figure 4] FIG. 2 is a schematic diagram of a first exemplary heating apparatus including a waste heat recovery unit according to an exemplary embodiment.

[0013] [Diagram 5] FIG. 2 is a schematic diagram of a second exemplary heating apparatus including multiple waste heat recovery units according to an exemplary embodiment.

[0014] [Figure 6] FIG. 13 is a schematic diagram of a third exemplary heating device including a drive device for generating electricity and driving a CO2 compressor, according to an exemplary embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Although the following text sets forth a detailed description of many different embodiments, it should be understood that the legal scope of the present invention is defined by the language of the claims set forth at the end of this patent. The detailed description should be construed as illustrative only and does not describe all possible embodiments, which would be impractical, if not impossible, to describe all possible embodiments. Those skilled in the art could implement numerous alternative embodiments that would still fall within the scope of the claims. Unless a term is expressly defined herein using the sentence "As used herein, the term 'is defined herein to mean ..." or a similar sentence, there is no intention to limit the meaning of the term beyond its plain or ordinary meaning. To the extent any term is referred to in this patent in a manner consistent with a single meaning, it is done only for clarity and is not intended to limit such claim term to that single meaning. Finally, unless a claim element is defined by reciting the word "means" and a function without describing any structure, the scope of any claim element is not intended to be interpreted under application of U.S. Patent Act 112(f).

[0016] The present disclosure provides novel processes, apparatus and systems that can be used individually or in combination to optimize utility costs associated with carbon capture processes, such as costs associated with cooling the post-combustion flue gas stream and costs associated with heating the heat transfer medium for solvent regeneration and CO2 stripping processes.

[0017] Turning now to the figures, Figure 1 shows an exemplary schematic diagram of a carbon capture facility 100. Facility 100 receives a post-combustion flue gas stream 10, which may be from an industrial facility or other combustion system. The flue gas stream 10 is conveyed through one or more components of system 100 along a fluid path defined by fluid connections or conduits 102-108. The direction of each of the arrows 102-108 in the illustration of Figure 1 represents a downstream direction of the flow path of the flue gas stream 10 from or to the component of system 100 at the end of the respective arrow.

[0018] For example, conduit 102 conveys the flue gas stream 10 downstream to a chiller 110. The chiller 110 is positioned upstream of the absorber 120 to cool the flue gas stream 10 exiting the chiller and flowing towards the absorber 120 via conduit 106. The flue gas stream 10 then exits the absorber 120 in conduit 108 as a flue gas stream having a lower CO2 concentration than the flue gas stream 10 entering the absorber 120. In one example, the flue gas stream 10 exiting the absorber 120 via conduit 108 may be released to the atmosphere. A bypass conduit 104 may be included to selectively divert the flue gas stream 10 (or a portion thereof) from the conduit 102 and away from other components of the carbon capture equipment 100 (e.g., away from the cooling device 110), and thus selectively bypass the carbon capture process; the bypass 104 also allows the host equipment to operate without operation of the carbon capture unit (e.g., the carbon capture equipment can be shut down for maintenance and the host equipment can still operate with the flue gas exiting through the bypass 104).

[0019] More generally, unless otherwise specified herein, arrows depicted in the figures of this disclosure (e.g., arrows 102-108, 112-118, 122-128, etc.) extending to or from various components may represent fluid connections or conduits (e.g., piping, etc.) configured to convey fluids (e.g., flue gas, air, solvent, water, etc.) from or to the components at the ends of the respective arrows. Additionally, the arrow direction of each arrow represents the flow direction (e.g., downstream direction) of fluid flowing within the conduit represented by the respective arrow.

[0020] The absorber 120 may include a contactor (e.g., gas-liquid contactor, gas-gas contactor, etc.) or any other type of device in which a lean absorbing medium contacts the flue gas stream 10 flowing therethrough to capture CO2 from the flue gas stream 10. The absorbing medium may be ammonia, amine-based, carbonate-based (e.g., potassium carbonate), ionic fluids, and / or any other type of solvent. Prior to contact with the flue gas stream 10, the solvent (e.g., “lean medium”) entering the absorber 120 (via conduit 112) is low in CO2. After contact with the flue gas stream 10, the solvent (e.g., “rich medium”) exiting the absorber 120 (via conduit 114) is rich in CO2. In an example, the rich solvent exiting the absorber 120 (via conduit 114) may contain a larger amount of CO2 (and / or a larger amount of carbon) than the lean solvent entering the absorber 120 (via conduit 112).

[0021] The solvent regeneration and CO2 stripping unit 130 may be disposed in fluid communication with the absorber 120 to receive rich solvent from the absorber 120 (via conduit 114) and to supply lean solvent to the absorber 120 (via conduit 112). To that end, the regeneration and CO2 stripping unit 130 may be interchangeably referred to herein as a solvent regenerator 130, a regenerator 130, a CO2 stripper 130, and / or a stripper 130. The regenerator / stripper 130 may be configured to convert the rich solvent to a lean solvent by removing CO2 (or carbon) from the rich solvent. To facilitate this, in one example, the regenerator 130 may heat the rich solvent using a heat medium (e.g., steam or oil) to remove or separate the CO2 (or carbon) from the rich solvent.

[0022] The system 100 may also include a heating device 140 configured to heat the heat transfer medium and provide the heated heat transfer medium to the regenerator 130 via conduit 116. In an example, the heating device 140 may include one or more combustion-based devices configured to heat the heat transfer medium, thus generating heating system flue gas. In an example, the heating system flue gas may be conveyed from the heating device 140 (e.g., via conduit 118) for combination with the flue gas stream 10 at the front end of the carbon capture system 100 (e.g., in conduit 102) or at any other location upstream of the CO2 absorber 120.

[0023] The regenerator / stripper 130 may output a CO2-rich stream comprising the CO2 extracted from the rich solvent to a conduit 122 for delivery of the CO2-rich stream to a compressor 150. The compressor 150 may compress the CO2-rich gas stream (received from the regenerator 130 via conduit 122) for other users or applications, such as sequestration (e.g., underground or underwater storage) or other industrial applications. In some examples, the compressor 150 is a multi-stage compressor.

[0024] The system 100 also includes a driver 160 coupled to the compressor 150. The driver 160 may be configured to provide mechanical energy to the compressor 150 to compress the CO2-rich stream (e.g., received by the compressor 150 from the conduit 122). In an example, the driver 160 may be an internal combustion engine or other type of combustion-based driver that combusts a fuel to generate mechanical energy to drive the compressor 150. As such, in some examples, the compressor driver 160 may generate driver flue gas (e.g., as a by-product of the fuel combustion by the driver 160). The driver flue gas may be conveyed from the driver 160 (via the conduit 124) to the heating device 140. For example, the heating device 140 may include a waste heat recovery unit (not shown in FIG. 1) configured to extract heat from the driver flue gas to heat a head medium that is provided to the regeneration and stripping unit 130 (via the conduit 116). Further, in one example, the drive flue gas may ultimately (e.g., after heat recovery in heating device 140) be redirected to the front end of the carbon capture process (e.g., upstream of cooling device 110) or to any other location upstream of CO2 absorber 120 (e.g., via conduit 118) for combination with flue gas stream 10.

[0025] System 100 may also include a CO2 dehydration and post-treatment unit 170 in fluid communication with compressor 150 to receive the compressed CO2 from compressor 150 via conduit 126. Dehydration and post-treatment unit 170 is configured to remove water and / or other components (e.g., contaminants, etc.) such that the compressed CO2 is of a suitable quality and composition for an end user of the compressed CO2. In the illustrated example, the post-treated and / or dehydrated compressed CO2 is conveyed from carbon capture system 100 via conduit 128.

[0026] In an example, compressor 150 and / or dehydration and post-treatment unit 170 send the compressed CO2 from system 100 (e.g., via conduit 128 or via another conduit not shown in FIG. 1 ) to a carbon user or sequestration site. In one example, the compressed CO2 may be sent to an off-site sequestration facility (not shown), such as a subterranean geological formation containing at least partially depleted hydrocarbon reservoirs, or any other sequestration site. In one example, the sequestration site may be above the ocean floor (e.g., at a depth of 3 kilometers or more below sea level). In one example, the sequestration site is below the ocean floor.

[0027] As discussed above, conventional carbon capture processes typically cool the flue gas using a cooling water quench system comprising a cooling tower (e.g., an "evaporative cooling water system"), which cools the flue gas by evaporating at least a portion of the cooling water. Such evaporative cooling water systems typically consume water from environmental sources or local utilities to replenish the evaporated water, and thus may have adverse environmental impacts. Additionally, in some facilities, it may not be feasible to continuously supply / replenish cooling water for the evaporative cooling water system due to the facility's location and / or other factors.

[0028] Accordingly, an exemplary cooling apparatus is disclosed herein, as described below in connection with Figures 2 and 3, that advantageously allows for cooling the flue gas stream without necessarily requiring the use of additional cooling water and / or without necessarily using an evaporative cooling water system. To facilitate this, the exemplary cooling apparatus may include one or more gas-to-air heat exchangers positioned to cool the flue gas stream 10 upstream of the CO2 absorber 120.

[0029] FIG. 2 is a schematic diagram of an example cooling device 200 that may be used, for example, to implement cooling device 110 of system 100.

[0030] In the illustrated example, the cooling system 200 includes a gas-to-air heat exchanger 210 disposed upstream of and in fluid communication with the absorber 120. In an example, the gas-to-air heat exchanger 210 may be a gas-to-gas heat exchanger that uses air as a cooling medium flowing through the heat exchanger 210. For example, the heat exchanger 210 may define separate flow paths for the air (entering the heat exchanger 210 at conduit 206 and exiting the heat exchanger at conduit 208) and the flue gas stream (entering the heat exchanger at conduit 202 and exiting the heat exchanger at conduit 204) such that the two gas streams (i.e., the cooling air and the flue gas stream) are not mixed with each other inside the heat exchanger 210. In one example, the flue gas stream 10 may enter the heat exchanger 210 through a first gas inlet (connected to conduit 202) of the heat exchanger 210 and may exit the heat exchanger through a first gas outlet (connected to conduit 204). Within the heat exchanger 210, heat from the flue gas flow 10 may be transferred to cooling air (e.g., ambient air) or other cooling medium that enters the heat exchanger 210 through a second gas inlet (connected to conduit 206) and exits the heat exchanger 210 through a second gas outlet (connected to conduit 208).

[0031] System 200 may also include at least one cooling air blower for moving air through gas-to-air heat exchanger 210, and at least one flue gas blower for moving the flue gas flow through gas-to-air heat exchanger 210 and CO2 absorber 120. In general, a blower is a device (e.g., a fan, etc.) structured to eject or move gas (e.g., flue gas or air) through, toward, and / or away from one or more components, and / or more generally, along a fluid path defined by a system, such as system 200.

[0032] 2 depicts two air blowers 212A-B in fluid communication with heat exchanger 210, in some examples system 200 may alternatively include only one of air blowers 212A-B. For example, system 200 may alternatively be implemented using a single cooling air blower disposed at one of locations 212A (upstream) or 212B (downstream) in fluid communication with heat exchanger 210. Each of locations 212A (upstream) and 212B (downstream) may provide different advantages, as described in more detail below.

[0033] In one example, the system 200 may include a cooling air blower 212A disposed upstream of the gas-to-air heat exchanger 210 to blow air (e.g., ambient air) toward the gas-to-air heat exchanger 210. In this upstream configuration, the air blower 212A may advantageously operate at improved efficiency due to the relatively low temperature of the air flowing through the air blower 212A (i.e., before it is heated inside the heat exchanger 210). The upstream configuration of the air blower 212A may also be associated with lower maintenance costs compared to a configuration in which the air blower blows a hotter airflow (e.g., downstream). On the other hand, the upstream air blower 212A may compress (and thus heat) the air entering the heat exchanger 210, potentially reducing the efficiency of the heat exchanger 210 in transferring heat from the flue gas flow 10 to the air compared to a configuration in which the air entering the heat exchanger 210 is relatively cool.

[0034] In one example, the system 200 may include a cooling air blower 212B disposed downstream of the gas-to-air heat exchanger 210 to blow air out of the gas-to-air heat exchanger 210 (i.e., after the air exits the heat exchanger 210 via conduit 208). In such a downstream configuration, the blower 212B may advantageously improve the cooling efficiency of the heat exchanger 210 by pulling air exiting the exchanger 210 (via conduit 208) instead of pushing air entering the exchanger 210 (via conduit 206). In particular, the downstream location of the air blower 212B may result in relatively cooler air entering the exchanger 210 because the air is not compressed (and thus heated) by the downstream air blower 212B until it exits the heat exchanger 210 (via conduit 208). On the other hand, the downstream location of air blower 212B may be associated with increased power requirements and / or maintenance costs (compared to the power requirements / maintenance costs associated with blowing cooler air) due to the relatively warm air flowing through blower 212B after it exits heat exchanger 210.

[0035] Thus, in some examples, a carbon capture process (e.g., system 100) implementing cooling system 200 can be optimized by selecting an appropriate location 212A (upstream) or 212B (downstream) for placing the cooling air blower depending on system parameters such as cooling efficiency requirements, parasitic load requirements, maintenance cost requirements, temperature range of flue gas stream 10, flow rate of flue gas stream 10, and / or any other parameters or tolerances specific to the industrial facility or carbon capture process using cooling device 200.

[0036] In some examples, the heat exchanger 210 can use a different type of gas as a cooling medium instead of or in addition to air. In one example, the flue gas stream exiting the absorber 120 (or a portion thereof) can be used to cool the relatively hot CO2 flue gas stream inside the heat exchanger 210, possibly in addition to or instead of ambient air. More generally, in some examples, the system 200 can advantageously enable the use of a gas (e.g., cooled air) as a cooling medium to cool the flue gas stream 10. For example, unlike evaporative cooling water systems that rely on water evaporation and use an external water source (e.g., a lake, a river, a local utility, etc.) to replenish the evaporated water, the system 200 can enable the use of ambient air and / or any other cooling gas medium that is readily available to the system 200 to cool the flue gas stream.

[0037] The system 200 also includes at least one flue gas blower 214A-C for moving the flue gas flow through the heat exchanger 210 and the absorber 120. Although FIG. 2 depicts three flue gas blowers 214A-C in fluid communication with the heat exchanger 210, the system 200 may alternatively include fewer or more flue gas blowers. In some examples, the system 200 is implemented using a flue gas blower located at one of the locations 214A-C without one or more other flue gas blowers. In one example, one of the locations 214A-C may be selected as the location of the flue gas blower coupled to the heat exchanger 210 depending on various applications of the system 200. As described in more detail below, each of the locations 214A-C may have different advantages that may be suitable for various different applications of the system 200.

[0038] In one example, the system 200 may include a flue gas blower 214A located upstream of the heat exchanger 210 to blow the flue gas flow 10 towards the heat exchanger 210. The flue gas blower at the location 214A may advantageously add energy to the flue gas flow 10 (in the form of heat due to compression by the blower 214A) before the flue gas flow 10 enters the heat exchanger 210. For example, the energy added by the upstream blower 214A (or a portion thereof) may potentially be removed or reduced by the heat exchanger 210. However, the flue gas blower located at the location 214A may receive a flue gas flow 10 having a relatively high temperature and therefore may require more power to operate than if it were blowing a relatively low temperature flue gas. Additionally, the blower 214A may need to be constructed using relatively expensive materials that can withstand high temperatures and / or may require more frequent maintenance operations compared to configurations in which the blower blows a relatively low temperature flue gas.

[0039] In one example, the system 200 may include a flue gas blower 214B located downstream of the gas-to-air heat exchanger 210 (and upstream of the absorber 120) to blow the flue gas flow 10 (after it has been cooled by the heat exchanger 210) out of the heat exchanger 210. The flue gas blower at location 214B may advantageously contact the flue gas flow 10 after it has been cooled by the heat exchanger 210. Due to the relatively low temperature of the flue gas flow at location 214B, the flue gas blower 214B may be associated with relatively lower power requirements, material costs, and / or maintenance costs as compared to the flue gas blower at location 214A. On the other hand, placing the flue gas blower at location 214B may result in energy being added to the flue gas stream 10 after it has been cooled by the heat exchanger 210 (i.e., heat due to compression by the flue gas blower 214B), thereby warming the flue gas stream entering the absorber 120 and potentially reducing the carbon capture efficiency of the solvent in the absorber 120. For example, a solvent may capture CO2 more efficiently at a lower temperature.

[0040] In one example, the system 200 may include a flue gas blower 214C located downstream of the absorber 120 to blow the flue gas stream from the absorber 120. As discussed above, the flue gas stream includes at least a portion of the flue gas stream 10 exiting the absorber 120 (after the CO2 is absorbed by the solvent in the absorber 120), and thus the flue gas stream has a lower CO2 concentration than the flue gas stream 10 entering the absorber 120. As such, the flue gas blower located at location 214C may advantageously blow a flue gas stream having a lower volume and lower temperature than the flue gas stream 10 at locations 214A-B, which may result in improved efficiency and / or reduced power load compared to blowing a higher volume of flue gas at a higher temperature. However, locating the flue gas blower at location 214C may be associated with higher installation and / or maintenance costs in some scenarios. For example, in some configurations, the flue gas flow may be output from the top surface of the absorber 120, and therefore using location 214C may require the flue gas blower to be installed at a relatively high height associated with relatively difficult structural requirements for efficiently and safely supporting the flue gas blower 214C at the higher height.

[0041] As discussed above, system 200 can be optimized by customizing the number and / or location of cooling air blowers and / or flue gas blowers depending on the particular parameters and tolerances (e.g., flue gas stream temperature, flue gas stream flow rate, parasitic load thresholds, cost requirements, etc.) of the carbon capture process using cooling system 200. For example, location 214A may be more desirable than location 214C, or vice versa, in some industrial facility applications.

[0042] The system 200 may also include a closed-loop water filtration unit 220 in fluid communication with the heat exchanger 210. For example, the closed-loop water filtration unit 220 may be coupled to a duct of the gas-to-air heat exchanger 210 to provide water (via conduit 212) that is sprayed into the flue gas stream 10 inside the heat exchanger 210 to separate and condense particulates. The condensed water containing the impurities (e.g., contaminants such as sulfur oxides) removed from the flue gas stream 10 may then be collected and returned (via conduit 214) to the closed-loop water filtration unit 220, where the water is filtered to remove the contaminants and returned to the heat exchanger 210 to complete the closed water filtration loop. In this arrangement, for example, removing these contaminants upstream of the absorber 120 can potentially improve the efficiency of the solvent in the absorber 120. Alternatively or additionally, although not shown, the closed-loop water filtration unit 220 may be coupled to the absorber 120 to cool and / or wash the flue gas stream exiting the absorber 120.

[0043] 3 is a schematic diagram of another exemplary cooling apparatus 300 including multiple gas-to-air heat exchangers 210, 310 disposed upstream of the absorber 120 in accordance with the present disclosure. In some scenarios, a single gas-to-air heat exchanger may be insufficient to cool the flue gas stream 10 to an appropriate temperature for efficient absorption of CO2 by the solvent inside the absorber 120. Therefore, in the illustrated example, one or more additional gas-to-air heat exchangers (e.g., heat exchanger 310) may be disposed upstream of the absorber 120 to further cool the flue gas stream 10 before it enters the absorber 120.

[0044] In the example of FIG. 3, gas-to-air heat exchanger 310 may receive and cool the flue gas flow 10 (via conduit 102), and then gas-to-air heat exchanger 210 may receive the cooled flue gas flow 10 and further cool the flue gas flow 10 before it flows into absorber 120.

[0045] To that end, in the illustrated example, the cooling system 300 may include a flue gas blower 214A, 214B, and / or 214C for moving the flue gas flow 10 through the heat exchanger 310, the heat exchanger 210, and the absorber 120. In one example, not shown, the system 300 may include a flue gas blower disposed upstream of the heat exchanger 310 instead of or in addition to the flue gas blowers 214A, 214B, and / or 214C.

[0046] Additionally, system 300 may include a cooling air blower 312A positioned upstream of heat exchanger 310 to blow cooling air toward and through heat exchanger 310 (e.g., similar to blower 212A of heat exchanger 210), and / or a cooling air blower 312B positioned downstream of heat exchanger 310 to blow and move cooling air toward and through heat exchanger 310 (e.g., similar to blower 212B of heat exchanger 210).

[0047] More generally, cooling systems 110, 200, 300, etc. of the present disclosure may be customized according to the needs of the industrial facility using the carbon capture process 100. Thus, the number and / or location of gas-to-air heat exchangers, cooling air blowers, and / or flue gas stream blowers used in systems 200 and / or 300 may be customized according to factors such as the flow rate of the input flue gas stream 10, the temperature of the input flue gas stream 10, power availability for the carbon capture process, among other factors specific to the industrial facility using the systems and processes of the present disclosure.

[0048] In line with the above discussion, the exemplary cooling systems 200, 300, etc. of the present disclosure can advantageously solve challenges associated with implementing a carbon capture process by enabling cooling of the flue gas stream without necessarily using an evaporative cooling water system that requires a makeup water flow.

[0049] As previously mentioned, adopting a carbon capture process in some industrial facilities can also be challenging due to the heat load requirements for the solvent regeneration and / or CO2 stripping processes, as well as the power load requirements (e.g., to operate blowers, etc.) associated with operating the carbon capture equipment, which may sometimes require significant upgrades to the industrial facility's existing infrastructure. Accordingly, Figures 4-6 show exemplary optimized heating and power generation equipment that can be used to optimize the carbon capture process and / or solve these challenges.

[0050] 4 is a schematic diagram of an exemplary carbon capture system 400 including an exemplary heating device for solvent regeneration and CO2 stripping according to the present disclosure. System 400 depicts an exemplary embodiment of system 100, in which heating device 140 includes a combustion heater 410, a waste heat recovery unit 420, and a generator 430.

[0051] The combustion heater 410 (e.g., an industrial furnace) is a heater that burns a combustion fuel and transfers heat from the combustion gases to a heat transfer medium that is transported from the combustion heater via conduit 116 to the regenerator 130. As mentioned above, the heat transfer medium may include any suitable heat transfer medium, such as steam or oil. The regenerator or stripper 130 uses the heated heat transfer medium to regenerate the CO2-rich solvent received from the absorber 120 into lean solvent by stripping CO2 from the rich solvent.

[0052] As a by-product of the combustion process in the combustion heater 410, the combustion heater 410 may generate heater flue gas. In the illustrated example, the heater flue gas is conveyed from the combustion heater 410 (via conduit 406) and combined with the flue gas stream 10 upstream of the absorber 120 (and / or upstream of the cooling device 110, the gas-to-air exchanger 210, and / or the gas-to-air exchanger 310). In some examples, the heater flue gas may be relatively cooler than the input flue gas stream 10, and thus may potentially improve the efficiency of the cooling device 110 by reducing the overall temperature of the combined flue gas stream 10 (including the heater flue gas).

[0053] 1, the driver 160 may include an internal combustion engine, a gas turbine, or any other type of combustion-based driver configured to provide mechanical energy to drive the compressor 150. As a product of this combustion process, the driver 160 produces driver flue gas. The driver flue gas is conveyed from the driver 160 via the conduit 124 to the waste heat recovery unit 420.

[0054] The generator 430 may also include a combustion-based generator, such as a gas turbine or combustion engine, that generates electrical power (e.g., electricity) to power one or more components of the carbon capture system (e.g., gas-to-air exchangers 210, 310, blowers 212, 214, 312, etc.). As such, the generator 430 produces generator flue gas that is conveyed from the generator 430 to the waste heat recovery unit 420 via conduit 402.

[0055] The waste heat recovery unit 420 is an energy recovery device (e.g., a heat exchanger) configured to transfer heat from the generator flue gas and / or drive flue gas to the heat medium to further heat the heat medium to supplement the heat from the combustion heater 410 before conveying the heated heat medium to the regenerator 130. In some examples, the regenerator 130 can return the spent heat medium (via conduit 404) to the combustion heater 410 and / or the waste heat recovery unit 420 for reheating the heat medium.

[0056] In this arrangement, the waste heat recovery unit 420 can enable a reduction in parasitic loads associated with heating the heat transfer medium by utilizing waste heat from the drive flue gas and / or generator flue gas to efficiently heat the heat transfer medium for the solvent regeneration and CO2 stripping processes (e.g., by reducing the total amount of fuel that would otherwise be consumed to heat the heat transfer medium without the waste heat recovery unit 420).

[0057] After recovering heat from the generator flue gas and / or drive unit flue gas, the flue gas is conveyed from the waste heat recovery unit 420 (e.g., via conduit 408) for combination with the flue gas stream 10 at the front end of the carbon capture system 400 (e.g., shown in FIG. 4 ) or any other location upstream of the absorber 120. In some examples, the flue gas exiting the waste heat recovery unit 420 is cooler than the input flue gas stream 10 and thus can facilitate improved efficiency of the chiller 110 and / or the absorber 120 by causing the combined flue gas stream 10 (including the flue gas from the waste heat recovery unit 420) to have a lower overall temperature.

[0058] 5 is a schematic diagram of an exemplary carbon capture system 500 including another exemplary heating device according to the present disclosure. System 500 depicts an exemplary embodiment of system 100 in which heating device 140 includes two waste heat recovery units 420, 520, a combustion heater 410, and a generator 430.

[0059] In particular, system 500 includes (similar to system 400) a first waste heat recovery unit 420 for receiving drive flue gas (via conduit 124) from drive 160, and a second separate waste heat recovery unit 520 for receiving generator flue gas 402 (via conduit 402) output from generator 430. Second waste heat recovery unit 520 extracts heat from generator flue gas entering waste heat recovery unit 520 from generator 430 (via conduit 402) to provide The heat transfer medium entering the regenerator 130 is further heated. For example, as shown, the heated heat transfer medium exits the waste heat recovery unit 520 via conduit 502 and is combined with the heated heat transfer medium output from the combustion heater 410 and / or waste recovery unit 420 upstream of the regenerator 130.

[0060] Further, in the illustrated example, the generator flue gas (after being used in the waste heat recovery unit 520 to heat the heat transfer medium) is transported from the waste heat recovery unit 420 (e.g., via conduit 508) for combination with the input flue gas stream 10 at the front end of the carbon capture process 500 (or any other location upstream of the absorber 120), consistent with the above description of the spent flue gas leaving the waste heat recovery unit 520.

[0061] In some examples, the location of the carbon capture system 500 may be advantageous in industrial facility applications where the generator 430 is not necessarily located near the compressor 150, the drive 160 and / or the waste heat recovery unit 420.

[0062] Although not shown, in some examples, the heater flue gas output from the combustion heater 410 may alternatively be redirected to a waste heat recovery unit 420, 520 and / or a separate waste heat recovery unit (not shown) to extract additional heat to further heat the heat carrier before combining the heater flue gas with the input flue gas stream 10.

[0063] 6 is a schematic diagram of an exemplary carbon capture system 600 including yet another exemplary heating device according to the present disclosure. System 600 depicts an exemplary embodiment of system 100 in which a single drive 160 is used for both generating electricity and driving compressor 150. That is, the same drive 160 in the configuration of system 600 can perform the functions described above for generator 430 of FIGS. 4-5 (e.g., generating electricity to power one or more components of system 600) as well as driving CO2 compression by compressor 150. For example, drive 160 of system 600 may be implemented as an internal combustion engine and / or gas turbine that generates electrical power for the various components of system 600 as well as mechanical energy to operate compressor 150.

[0064] In line with the above description, the waste heat recovery unit 420 can receive the drive flue gas from the drive 160 (via conduit 124) and can use heat from the drive flue gas to heat a heat medium flowing from the waste heat recovery unit 420 to the regenerator / stripper 130.

[0065] The term "and / or" as used in this specification, including the claims, is an inclusive or exclusive conjunction. Thus, the term "and / or" means that there is more than one item in a group, or that a selection may be made from a group of alternatives.

[0066] Numerous features and advantages of the present disclosure are apparent from the written description, and therefore, the appended claims are intended to cover all such features and advantages of the present disclosure. Moreover, since numerous modifications and changes will readily occur to those skilled in the art, the present disclosure is not limited to the exact configuration and operation shown and described. Therefore, the described embodiments should be construed as illustrative rather than restrictive, and the present disclosure should not be limited to the details given herein, but should be defined by the full scope of the following claims and their equivalents, regardless of present or future foreseeable or unforeseeable.

Claims

1. 1. A method for treating a flue gas stream, comprising: receiving, in a solvent regenerator, a rich solvent flowing from a carbon dioxide absorber, the flue gas stream flowing through the carbon dioxide absorber, the rich solvent comprising carbon dioxide captured from the flue gas stream in the carbon dioxide absorber; heating a heat transfer medium using at least a combustion heater; conveying the heated heat transfer medium from the combustion heater to the solvent regenerator; generating combustion heater flue gas with the combustion heater; conveying the combustion heater flue gas into the flue gas stream at a location upstream of the carbon dioxide absorber; generating generator flue gas with a generator in fluid communication with a generator flue gas waste heat recovery unit, said generator generating electricity; conveying the generator flue gas from the generator to the generator flue gas waste heat recovery unit; Including, Heating the heat medium using the generator flue gas waste heat recovery unit is based on heat recovered from the generator flue gas by the generator flue gas waste heat recovery unit. method.

2. 2. The method of claim 1, further comprising conveying the generator flue gas from the generator flue gas waste heat recovery unit into the flue gas stream upstream of the carbon dioxide absorber.

3. 1. A method for treating a flue gas stream, comprising: receiving, in a solvent regenerator, a rich solvent flowing from a carbon dioxide absorber, the flue gas stream flowing through the carbon dioxide absorber, the rich solvent comprising carbon dioxide captured from the flue gas stream in the carbon dioxide absorber; heating a heat transfer medium using at least a combustion heater; conveying the heated heat transfer medium from the combustion heater to the solvent regenerator; generating combustion heater flue gas with the combustion heater; conveying the combustion heater flue gas into the flue gas stream at a location upstream of the carbon dioxide absorber; driving a carbon dioxide compressor using a drive device, the drive device generating drive device flue gas; conveying the drive unit flue gas from the drive unit to a waste heat recovery unit; Including, The method, wherein heating the heat transfer medium using the waste heat recovery unit is based on heat recovered by the waste heat recovery unit from the drive flue gas.

4. 4. The method of claim 3, further comprising conveying the drive flue gas from the compressor drive waste heat recovery unit into the flue gas stream upstream of the carbon dioxide absorber.

5. The method of claim 3 , wherein the drive device is an internal combustion engine.

6. 1. A system for treating a flue gas stream, comprising: a carbon dioxide absorber configured to receive the flue gas stream; a solvent regenerator in fluid communication with the carbon dioxide absorber and configured to receive rich solvent from the carbon dioxide absorber; a combustion heater in fluid communication with the solvent regenerator and configured to heat and convey a heat transfer medium toward the solvent regenerator, the combustion heater being further configured to generate combustion heater flue gas and convey the combustion heater flue gas from the combustion heater for combination with the flue gas stream at a location upstream of the carbon dioxide absorber; A system comprising:

7. The system of claim 6 , further comprising a waste heat recovery unit in fluid communication with the heat transfer medium and configured to further heat the heat transfer medium.

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