Department of Environmental Science and Engineering, Sichuan University, Chengdu 610065, China.
J Hazard Mater. 2011 Aug 15;192(1):124-30. doi: 10.1016/j.jhazmat.2011.04.104. Epub 2011 May 5.
NO was oxidized into NO(2) first by injecting ozone into flue gas stream, and then NO(2) was absorbed from flue gas simultaneously with SO(2) by pyrolusite slurry. Reaction mechanism and products during the absorption process were discussed in the followings. Effects of concentrations of injected ozone, inlet NO, pyrolusite and reaction temperature on NO(x)/SO(2) removal efficiency and Mn extraction rate were also investigated. The results showed that ozone could oxidize NO to NO(2) with selectivity and high efficiency, furthermore, MnO(2) in pyrolusite slurry could oxidize SO(2) and NO(2) into MnSO(4) and Mn(NO(3))(2) in liquid phase, respectively. Temperature and concentrations of injected ozone and inlet NO had little impact on both SO(2) removal efficiency and Mn extraction rate. Specifically, Mn extraction rate remained steady at around 85% when SO(2) removal efficiency dropped to 90%. NO(x) removal efficiency increased with the increasing of ozone concentration, inlet NO concentration and pyrolusite concentration, however, it remained stable when reaction temperature increased from 20°C to 40°C and decreased when the flue gas temperature exceeded 40°C. NO(x) removal efficiency reached 82% when inlet NO at 750 ppm, injected ozone at 900 ppm, concentration of pyrolusite at 500 g/L and temperature at 25°C.
首先通过向烟道气中注入臭氧将 NO 氧化为 NO(2)，然后用软锰矿浆同时从烟道气中吸收 NO(2)和 SO(2)。在接下来的内容中讨论了吸收过程中的反应机制和产物。还研究了注入臭氧、入口 NO、软锰矿和反应温度对 NO(x)/SO(2)去除效率和 Mn 提取率的影响。结果表明，臭氧可以选择性地高效地将 NO 氧化为 NO(2)，此外，软锰矿浆中的 MnO(2)可以分别将 SO(2)和 NO(2)氧化成 MnSO(4)和 Mn(NO(3))(2)在液相中。温度、注入臭氧浓度和入口 NO 对 SO(2)去除效率和 Mn 提取率的影响都很小。具体来说，当 SO(2)去除效率降至 90%时，Mn 提取率稳定在 85%左右。NO(x)去除效率随臭氧浓度、入口 NO 浓度和软锰矿浓度的增加而增加，但当反应温度从 20°C 升高到 40°C 时保持稳定，当烟道气温度超过 40°C 时则降低。当入口 NO 为 750 ppm、注入臭氧为 900 ppm、软锰矿浓度为 500 g/L、温度为 25°C 时，NO(x)去除效率达到 82%。
