Contribution to the study of sulphur dioxide transformation in power plant plumes: Tests in laboratory and on flue gases of an oil-fired power plant

Abstract In order to study more exactly the physico-chemical transformation of sulphur dioxide in the early history of power plant plumes, tests were made on synthetic gas mixtures and on the flue gases ot the Porcheville B power plant. For this purpose, a container of 1 m 3 was set up, and the results of the test apparatus were analysed, using chemical kinetic reactions already known in respect to the transformation of NO and NO 2 . The test device was subsequently used to study chemical changes of a variety of mixtures of nitrogen oxides and sulphur dioxide in the presence or absence of light, in both the homogenous and heterogeneous phases (effects of vanadium pentoxide and water). In a second stage the same test device was used to study the changes of sulphur dioxide in actual stack exhausts. The main conclusion of the study showed the low transformation rate of SO 2 to SO 3 in the gaseous phase before condensation of water in the plume.