In this study, research was carried out on absorber (in and exit) in the wet flue gas desulfurization (WFGD) system of a local thermal power plant. WFGD plays a vital role in terms of environment since it includes water, chloride ion, gypsum, and coal ash. In the progress of WFGD in power plants, absorber has the key role of SO2 removal. This study focuses on modeling of the absorber in the WFGD system. In the context of this study, sample from absorber in limestone slurry was analyzed based on particle size distribution (PSD) and elemental composition, and a model was proposed to predict SO2 removal rate. The model proposed employs basically the parameters previously proposed by some researchers, and in addition, the PSD, i.e., size parameters like D32 and D43. The model proposed is in good agreement with the results obtained.