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

• Published in: International journal of greenhouse gas control 2020-02, Vol.93, p.102904, Article 102904
• Main Authors: Fang, Mengxiang, Yi, Ningtong, Di, Wentao, Wang, Tao, Wang, Qinhui
• Format: Article
• Language: English
• Subjects: Aerosol; Chemical absorption; CO2 capture; Emission control; Pollutant
• ISSN: 1750-5836; 1878-0148
• DOI: 10.1016/j.ijggc.2019.102904

•Pollutants emissions and control methods of CO2 chemical absorption system were summarized.•The formation mechanism and influencing factors of pollutant emissions were discussed.•The chemical reaction in the absorber can significantly promote heterogeneous nucleation and accelerate the aerosol growth.•Pretreatment methods remove condensation nuclei in flue gas can effectively control pollutants emissions. 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.