Emission characteristics of Cl₂ and ClO₂ during simultaneous removal of SO₂ and NO using NaClO₂ solution

In this study, an experimental apparatus of oxidation + absorption columns was set up to investigated ClO₂ and Cl₂ emission characteristics when NaClO₂ was used as oxidant. Two sets of experiments were designed and compared, one was sampled every 15 min for 2 h and the other one was continuous sampling for 2 h. The results show that the concentration of ClO₂ in the outlet of oxidation column increased first and then decreased while Cl₂ barely changed during the experiment. The concentration of Cl₂ was far less than ClO₂, which indicated that the chlorine-containing gaseous component was mainly in the form of ClO₂. After 2 h reaction, the chlorine-containing ions in oxidation liquid before and after reaction were in good consistence with the theoretical calculation. High concentration of Cl^- was detected in the absorption liquid, while no ClO₂ ^- and ClO₃ ^- existed. As the reaction proceeded, the oxidation liquid gradually turned into light yellow, and pungent odor released. (paper)