A new Method for CO2 CaptureFrosting CO2 at Atmospheric Pressure

Design of a cryogenic CO2 capture system based on Stirling coolers

“…Considering the post-combustion flue stream is typically composed by 13.9% CO 2 , 75.5% N 2 (which has a frost point approximately −209.86 • C), 5.1% O 2 (which has a frost point approximately −218 • C) and 5.5% H 2 O (Clodic and Younes, 2002), it is convenient to carry out this separation using cryogenic processes, and under the low temperature condition, most of the CO 2 can desublimate and be separated from the gaseous phase.…”

Simultaneous removal of CO2, SO2, and NOx from flue gas by liquid phase dehumidification at cryogenic temperatures and low pressure

“…Cryogenic cycles have been proposed in which condensation of CO 2 occurs, forming 'dry ice' at temperatures well below the triple point and crucially with the flue gas at or near to atmospheric pressure [8]. Frosting methods for removing CO 2 from gas streams are not new, having been used in the ethylene industry, for example, since the 1930s [9].…”

A preliminary investigation of cryogenic CO2 capture utilizing a reverse Brayton Cycle

“…In order to capture 90% of the CO 2 , in the gas mixture into its liquid form, the process consumes about 0.395 MJ per kg of CO 2 with a resulting CO 2 purity of over 99% [13] . The advantages of cryogenic CO 2 capture techniques, as readily recognizable from the above examples, are: (1) the energy penalty of solvent regeneration and generated pressure drop can be neglected [4][5][6][7][8][9][10][11][12][13] ; (2) CO 2 can be captured in the liquid or solid phase, enabling compression without the huge energy consumption associated with gaseous compression, and providing a convenient means for storage and transport [4][5][6] ; (3) the compression, expansion and refrigeration technologies in the cryogenic CO 2 capture system are all relatively mature industrial processes, and can be easily utilized on an industrial-scale [10,13] ; (4) various refrigeration byproducts will be produced in some systems, such as high purity N 2 , and these can reduce the operation cost of the plant [14] . Nevertheless, to extract CO 2 from the other components in the flue gas (typically as N 2 , CO 2 , H 2 O, NO x , SO x ), a very low-temperature is required, resulting in the following problems [4][5][6][7][8][9][10][11][12][13] : (1) a large amount of energy is consumed for the refrigeration, leading to a high energy penalty for capture, and the process covers a large range of operating conditions from normal to supercritical states; (2) in the anti-sublimation processes, CO 2 will be frozen on the cold surfaces of the flow channels or heat exchangers, potentially causing several operational problems, such as plugging; (3) for the pre-combustion power plant and the oxy-fuel power plant, a large amount of additional energy is consumed in the hydrogen production or air separation unit; (4) acidic gas, such as NO x , SO x , may damage the devices, and shorten their operational life time.…”

“…Examples of the first approach include those of Clodic and Younes [4] who in 2002 and 2005 proposed a CCC system at atmospheric pressure, which froze CO 2 as a solid on the cold surfaces of heat exchangers by evaporating a refrigerant blend. To avoid plugging the flow through the heat exchangers, a swing process was designed that recovered the sublimation and melting energy of the CO 2 during the defrosting process.…”