Advanced experimental analysis of the reaction of Ca(OH)2 with HCl and SO2 during the spray dry scrubbing process

The experimental results showed that the SO2 removal efficiencies were higher in the presence of HCl (120-500 ppm) than in the absence of HCl at 250 °C and 20% relative humidity (RH). However, the removal efficiency of SO2 decreased as the HCl concentration increased. The removal efficiency of SO2 also increased with the amount of CaCl2 in the spray dryer.