Radiation-induced sulfur dioxide removal

The biggest source of air pollution is the combustion of fossil fuels, wher e pollutants such as particulate, sulfur dioxide (SO2), nitrogenoxides (NOx ), and volatile organic compounds (VOC) are emitted. Among these pollutants , sulfur dioxide plays the main role in acidification of the environment. T he mechanism of sulfur dioxide transformation in the environment is partly photochemical. This is not direct photooxidation, however, but oxidation th rough formed radicals. Heterogenic reactions play an important role in this transformation as well; therefore, observations from environmental chemist ry can be used in air pollution control engineering. One of the most promis ing technologies for desulfurization of the flue gases (and simultaneous de nitrification) is radiation technology with an electron accelerator applica tion. Contrary to the nitrogen oxides (NOx) removal process, which is based on pure radiation-induced reactions, sulfur dioxide removal depends on two pathways: a thermochemical reaction in the presence of ammonia/water vapor and a radiation set of radiochemical reactions. The mechanisms of these re actions and the consequent technological parameters of the process are disc ussed in this paper. The industrial application of this radiation technolog y is being implemented in an industrial pilot plant operated by INCT at EPS Kaweczyn. A full-scale industrial plant is currently in operation in China , and two others are under development in Japan and Poland.