摘要 |
Disclosed is a process for removing sulfur oxides and optionally other gaseous pollutants from flue gases by means of a reactant which is contained in a circulating fluidized bed and contains sodium, potassium, calcium and/or magnesium as a cation and oxide, hydroxide and/or carbonate as an anion. The adaptation to all operating conditions of the plants by which the flue gas is supplied is simplified in that pollutants are removed from the flue gases when the temperature of the mixture of flue gas and reactant is not in excess of 50 DEG C. above the dew point temperature of water vapor. The reactant is selectively charged at different locations in a dry form, on the one hand, and as an aqueous solution or suspension, on the other hand, the form in which the reactant is charged being controlled in dependence of the temperature and the SO2 content of the purified gas. If the reactant is charged in a liquid phase it has suitably a solids content of 5 to 30 wt. %, the temperature of the mixture of flue gas and reactant is maintained between 3 DEG and 30 DEG C. above the dew point temperature of water vapor and the means suspension density in the fludized bed reactor is maintained between 0.2 and 2 kg/m3.
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