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The Capture and Sequestration of Carbon Dioxide | | |
Physical absorption/adsorption
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In which a solid absorbent (such as activated carbon, zeolites) is passed through the gas stream, and
the CO2 is held on the surface of the particles by (non-chemical) surface forces. Once collected,
the particles are heated, releasing (desorbing) the CO2.
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In pressure swing adsorption (PSA), the gas mixture flows through a packed bed of adsorbent at elevated
pressure until the adsorption of the desired gas
approaches equilibrium conditions at the bed exit. The bed is then regenerated by stopping the feed
mixture and reducing the pressure.
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In temperature swing adsorption (TSA), the adsorbent is regenerated by raising its temperature.
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Adsorption is not yet considered attractive for large-scale separation of CO2 from flue gas
because the capacity and CO2 selectivity of available adsorbents is
low. However, it may be successful in combination with another capture technology.
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Electric Swing Adsorption (ESA)
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