The dry removal process of sulphur dioxide from flue gases using aluminum oxide

Oxidation of sulfur dioxide to sulfur trioxide and absorption on aluminum oxide pellet as a mean of removing sulfur dioxide from flue gas was studied in a packed bed reactor at various temperatures, residence times, SO2 inlet concentrations (ppm level), and particle sizes. Three different experiments were conducted: (i) sulfation with oxygen/ozone, (ii) sulfation with oxygen only in the presence of UV radiation ( 254 nm or 366 nm ), (iii) sulfation with oxygen only. In all the experiments substantial absorption of sulfur dioxide by alumina pellet was observed. Sulfation with oxygen/ozone give the highest absorption of SO2, followed by sulfation with oxygen in the presence of UV radiation, while sulfation with oxygen only had the lowest absorption. In all these experiments, the absorption of SO2 decreases with increasing SO2 concentration, increases with increasing residence time, and increases with decreasing particle size. At SO2 concentration of 8,352 ppm, residence time of 0.018 sec., and particle size of 0.3175 cm, sulfation with oxygen/ozone and sulfation with oxygen only in the presence of UV radiation attain maximum absorption at about 275°C, whereas sulfation with oxygen only attains maximum absorption at about 640°C