BACKGROUND

Industrial facilities that utilize combustion fuels may generate greenhouse gases. Greenhouse gases include various gaseous compounds, such as carbon dioxide, methane, nitrous oxide, hydrofluorocarbons, perfluorocarbons, and sulfur hexafluoride for example, which absorb radiation, trap heat in the atmosphere, and/or otherwise contribute to undesirable environmental greenhouse effects.

Carbon capture processes can be employed to remove and/or reduce greenhouse gas emissions. There are several challenges associated with traditional implementations of post combustion carbon capture processes in industrial facilities. One challenge involves parasitic power loads which may negatively impact the output and efficiency of an industrial facility that employs the carbon capture process. Another challenge involves additional cooling water loads traditionally used in carbon capture systems and the environmental impacts related to the use of such additional cooling water. To enable effective absorption of carbon dioxide from a flue gas and reduce degradation of the absorbing media, 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 a stream of make-up fresh water to replenish their cooling water loop, and thus place a significant demand on utilities and fresh-water sources.

SUMMARY

The present disclosure provides novel and improved carbon capture systems, devices, facilities, and methods. In an example, a method for processing a flue gas stream involves cooling the flue gas stream using at least a gas-to-air heat exchanger disposed upstream of and in fluid communication with a carbon dioxide (CO2) absorber. The method also involves moving, by a flue gas blower, the flue gas stream through the gas-to-air heat exchanger and the CO2 absorber. The method also involves moving, by a cooling air blower, air through the gas-to-air heat exchanger to cool the flue-gas stream.

In an example, a method for processing a flue gas stream involves receiving, at a solvent regenerator, a rich solvent flowing from a carbon dioxide (CO2) absorber. The rich solvent includes CO2 captured from the flue gas stream in the CO2 absorber. The method can also involve heating a heat medium using at least a fired heater, where additional heat is not available in the host facility. The method also involves transporting the heated heat medium from the fired heater to the solvent regenerator. The method also involves generating a fired heater flue gas by the fired heater. The method also involves transporting the fired heater flue gas into the flue gas stream at a position upstream of the CO2 absorber.

In an example, a system for processing 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 to receive and cool the flue gas stream. The gas-to-air heat exchanger to transport the cooled flue gas stream through and out of the gas-to-air heat exchanger toward the CO2 absorber. The system also includes a flue gas blower to move the flue gas stream through the gas-to-heat exchanger and the CO2 absorber. The system also includes a cooling air blower to move air through the gas-to-air heat exchanger to cool the flue gas stream.

In an example, a system for processing a flue gas stream includes a carbon dioxide (CO2) absorber to receive the flue gas stream. The system also includes a solvent regenerator in fluid communication with the CO2 absorber. The solvent regenerator to receive a rich solvent from the CO2 absorber and to provide a lean solvent to the CO2 absorber. The lean solvent having a lower amount of CO2 than the rich solvent. They system also can include a fired heater in fluid communication with the solvent generator, where additional waste heat is not available from the host facility. The fired heater to heat and transport a heat medium toward the solvent regenerator. The fired heater to generate a fired heater flue gas and transport the fired heater flue gas out of the fired heater for combination with the flue gas stream at a position upstream of the CO2 absorber.

Additional examples, features, and advantages of the disclosed devices, systems, facilities, and methods are described in, and will be apparent from, the following Detailed Description and the Figures. The features and advantages described herein are not all-inclusive and, in particular, many additional features and advantages will be apparent to one of ordinary skill in the art in view of the figures and description. Also, a particular embodiment does not necessarily have all of the advantages listed herein. Moreover, it should be noted that the language used in the specification has been principally selected for readability and instructional purposes, and not to limit the scope of the inventive subject matter.

