Simultaneous desulfurization and denitrification of sintering flue gas via composite absorbent

Experiments on simultaneous absorption of SO₂ and NO_X from sintering flue gas via a composite absorbent NaClO₂/NaClO were carried out. The effects of various operating parameters such as NaClO₂ concentration (m_s), NaClO concentration (m_p), molar ratio of NaClO₂/NaClO (M), solution temperature (T_R), initial solution pH, gas flow (V_g) and inlet concentration of SO₂ (C_S) and NO (C_N) on the removal efficiencies of SO₂ and NO were discussed. The optimal experimental conditions were determined to be initial solution pH=6, T_R=55℃ and M=1.3 under which the average efficiencies of desulfurization and denitrification could reach 99.7% and 90.8%, respectively. Moreover, according to the analysis of reaction products, it was found that adding NaClO to NaClO₂ aqueous solution is favorable for the generation of ClO₂ and Cl₂ which have significant effect on desulfurization and denitrification. Finally, engineering experiments were performed and obtained good results demonstrating that this method is practicable and promising.