Abstract:
The chemical absorption method regarded as the leading capture technology is expected to be developed more broadly driven by the dual carbon target. However, the high regeneration energy of solvent stems its further development. In recent years, a novel water-lean solvent has caught huge attention due to its significant potential in the reduction of regeneration energy. Three different types of water-lean solvents classified by the absorbent including homogenous amine based water-lean solvents, biphasic solvents, ionic liquid, aminosilicone and CO
2BOL are introduced in this paper. The key factors of the solvent evaluation like thermodynamic behavior, kinetics, physical property are elucidated and compared among different water-lean solvents. An average regeneration energy of 2.3 GJ/tCO
2 of water-lean solvents is much lower than that of MEA aqueous solvent, making them more favorable for industrial applications. A higher viscosity of rich solvent is gained in water-lean solvent compared with MEA solvent, while homogenous water-lean solvents exhibit an average viscosity of 10.3 mPa·S, which is comparable to traditional blended amine. This characteristic allows homogeneous water-lean solvents to be used in the existing heat exchangers of CO
2 capture system without requiring any additional optimization.