Abstract: A method of desulfurizing boiler flue gas by intimate contact thereof with dry particles of a reactant or absorbent, such as hydrated lime, preferably with recirculation of the flue gas and entrained reactant or absorbent particles. An apparatus suitable for carrying out the method comprises an upstanding conduit defining a vertical gas flow path in communication with a source of SO.sub.2 --and particulate-laden flue gas, a conveyor for introducing a dry reactant or absorbent into the gas flow path, and a rotatable slinger mounted within the gas flow path for uniformly distributing the reactant or absorbent thereacross.