Aerosol Emissions of Amine-Based CO Absorption System: Effects of Condensation Nuclei and Operating Conditions.

Amine emissions from a post-combustion CO capture process can lead to solvent loss and serious environmental issues. The emission characteristics of amine mixtures and influencing factors are seldom reported. This work comprehensively investigated emissions of AMP (2-amino-2-methyl-1-propanol)/MEA (monoethanolamine) from a 3.6 Nm/h flue gas CO capture platform. The condensation nuclei in flue gas dominated the generation of amine aerosols and resulted in a heavy total amine loss of over 1400 mg/Nm, which is equivalent to 5.88 kg/t CO captured under the high nuclei concentration scenario. Inside the absorber, a higher CO concentration and lower lean solvent CO loading can significantly promote the growth of aerosols due to the intensive reaction of CO absorption. The maximum amine emissions were observed at 8-12 vol % CO. The flue gas temperature and liquid/gas ratio had insignificant effects on aerosol emissions, while amine emissions after the absorber increased 340-500% as the lean solvent temperature increased from 30 to 50 °C. A synergistic control strategy of nuclei pretreatment, operating optimization, and water scrubbing can effectively reduce amine emissions to 4.0 mg/Nm MEA and 8.3 mg/Nm AMP.