Simultaneous absorption of SO₂ and NO in a stirred tank reactor with NACLO₂/NAOH solutions

The wet scrubbing combined SO_x/NO removal system is one of the advanced air pollution control devices. This study tries to understand the kinetics of the absorption in the system. The absorption of SO₂ and simultaneous absorption of SO₂ and NO, whose concentrations are typical for flue gases emitted from coal-fired power plants, in a stirred tank reactor with NaClO₂/NaOH solutions were carried out at 50°C. The liquid-side and gas-side mass transfer coefficients of the system were determined. The results indicate that the absorption of SO₂ is completely gas-film controlled if the NaOH concentration is greater than 0.1 M or the NaClO₂ concentration is greater than 0.2 M. Adding SO₂ would decrease the absorption rate of NO; however, the addition of NO has no effect on the absorption rate Of SO₂. The existence of O₂ has no significant effect on the absorption rate Of SO₂ and NO in the combined SO_x/NO removal tests.