Emission and control of flue gas pollutants in CO₂ chemical absorption system – A review

Chemical absorption is currently the most promising large-scale CO₂ capture technology due to its high capture efficiency, mature process, and good compatibility. While this process uses solvent to absorb the CO₂ from flue gas in absorption column, part of the solvents and its degradation products are discharged with the flue gas, causing new environmental pollution. This paper introduces the pollutants emission situation of chemical absorption CO₂ capture process. The characteristics of three typical emission forms, including physical entrainment, gas and aerosol, are systematically depicted. Then, the formation mechanism and influencing factors of pollutant emissions are discussed. And the effect of flue gas nuclei and absorber conditions on aerosol emissions are also described. Finally, the paper summarizes the effects, advantages, and disadvantages of different emission control methods. This review can provide guidance for industrial applications of chemical absorption systems.