Abstract
Thermal power plants are the biggest source of global warming because they emit huge amount of CO2. CCS (Carbon dioxide Capture & Storage) system that separates CO2 from boiler flue gas by using CO2 capture solvent is expected for remarkable reduction of CO2 emission from thermal power plants. This paper describes chemical absorption method of CCS for thermal power systems, especially the results of our research and development in refinement of amine solvent for CO2 capture using ion exchange treatment. Sulfur oxides such as SO4 and nitrogen oxides such as NO3- are contained in boiler flue gas as impurities. These impurities block the adsorption of CO2 and cause the significant performance degradation of CCS system. Adsorption and desorption behaviors of SO42- and NO3- by ion exchange resin are studied here in terms of small scale experiment and numerical analysis. The obtained results explain that two types of impurities such as SO42- and NO3- , in which SO42- has larger adsorption energy onto ion exchange resin than NO3- , show the temporal excess of NO3 concentration in amine solvent after ion exchange treatment. It is concluded that knowledge acquired here can be extended for design of ion exchange resin tower for boiler flue gas of CCS plant operation.
