Direct conversion of NO and SO 2 in flue gas into fertilizer using ammonia and ozone.

This study focused on the simultaneous removal of NO and SO ₂ from an industrial flue gas stream. To evaluate the removal efficiency of NO and SO ₂ using O ₃ and NH ₃ , the consumption of two reactants (O ₃ and NH ₃ ) in line with the conversion of NO and SO ₂ was quantified experimentally. In addition, NO and SO ₂ were converted to valuable fertilizers, NH ₄ NO ₃ and (NH ₄ ) ₂ SO ₄ . To identify a principle strategy to enhance the generation of fertilizer, Fourier transform infrared spectroscopy was used to examine the reaction mechanisms for the formation of NH ₄ NO ₃ and (NH ₄ ) ₂ SO ₄ . Acceleration of SO ₂ oxidation could be achieved effectively by adding NO to a gas mixture of SO ₂ , NH ₃ , and O ₃ . The formation of HNO ₃ might be enhanced by the simultaneous feeding of NO and SO ₂ . Particle generation was also 10 times higher for NH ₃ /(NO + SO ₂ ) than for NH ₃ /NO and for NH ₃ /SO ₂ , which is a prominent feature of this study. Moreover, the introduction of steam had a positive influence on particle generation. This method offers dual applications for NO and SO ₂ removal from a flue gas stream and direct fertilizer generation.
Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
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