Analysis of Energetics and Economics of Sub-ambient Hybrid
Post-Combustion CO2 Capture
Abstract
Adsorption of CO2 from post-combustion flue gas is one of the leading
candidates for globally-impactful carbon capture systems. This work
highlights opportunities and limitations of sub-ambient CO2 capture
processes utilizing a multi-stage separation process. A hybrid process
design using a combination of pressure-driven separation of CO2 from
flue gas followed by CO2-rich product liquefaction to produce high
purity (>99%) CO2 at pipeline conditions is considered.
The economic viability of applying pressure swing adsorption (PSA)
processes using fiber sorbent contactors with internal heat management
were found to be most influenced by the productivity of the adsorption
system. Three exemplar fiber sorbents (MIL-101(Cr), UiO-66, and zeolite
13X) were considered for application in the sub-ambient process of PSA
unit. MIL-101(Cr) and UiO-66 fiber composites were estimated to have
costs of capture as low as $61/tonne CO2.