The aim of this work is to investigate the SO2 capture capacity and sulfation rates of CaO-rich purges from a post-combustion CO2 capture calcium looping (CaL) large-scale pilot plant (a 1.7 MWth pilot plant operating in continuous mode). The sulfation reaction in simulated flue gas conditions was studied using a thermogravimetric analyzer (TGA), and isothermal sulfation tests were conducted over a range of temperatures to derive the kinetic parameters. It was confirmed that CaO-rich purges from CaL are able to capture more than twice as much SO2 as the parent fresh calcined limestone. This is because the pore blockage mechanism has less impact on the sulfation of highly cycled CaO purges from the CO2 capture system. Scanning electron microscopy (SEM)-energy-dispersive X-ray (EDX) analysis confirmed the homogeneous sulfation pattern of the cycled samples obtained from the pilot. A semi-empirical model based on the random pore model (RPM) was used to fit the experimental results. The kinetic parameters k(s) and D-p were calculated using the experimental data obtained from TGA tests. The values obtained are consistent with those obtained by other authors for non-cycled materials.