CO2 Sorption Characteristics of Various Sorbents in the Bubbling Fluidized-Bed

Abstract

This study reports the performance of base-impregnated silica and activated carbons supplied by the University of Nottingham (UNOTT) have been tested in the bubbling fluidized-bed reactor and the two interconnected bubbling fluidized-beds in a continuous system. UNOTT has published several papers with polyethyleneimine (PEI)-silica sorbents using a bubbling fluidized-bed reactor, reporting that the average working capacity was around 8.0wt.% and the regeneration heat was around 3.3 GJ/tCO2 based on the cycle tests. In order to verify the performance of this silica adsorbent and to draw comparison with activated carbons that potentially offer have lower regeneration energies, KIER has carried out cycle experiments using a bubbling fluidized bed reactor and also used a continuous CO2 capture system which consists of a bubbling fluidized-bed-type absorption and regeneration reactors. Further, the sorption characteristics, including equilibrium capacity, kinetics, surface area, pore size distribution, were determined using a volumetric (BET) and a gravimetric (MSB, magnetic suspension balance methods. The sorption mechanism of CO2 on the sorbent surface was investigated by in situ FT-IR. The optical, physical and chemical characteristics were examined by SEM- EDAX, TGA before and after the sorption - desorption cyclic tests. Particle size distribution of the sorbent was also analyzed by laser diffraction particle size analyzer.