Simultaneous absorption of NOx and SO2 from flue gas with pyrolusite slurry combined with gas-phase oxidation of NO using ozone
Simultaneous absorption of NOx and SO2 from flue gas with pyrolusite slurry combined with gas-phase oxidation of NO using ozone
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DOI：
10.1016/j.jhazmat.2011.04.104
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发表时间：
2011-08-15
影响因子：
13.6
通讯作者：
Jiang Wen-ju
中科院分区：
文献类型：
--
作者：
Sun Wei-yi;Ding Sang-lan;Jiang Wen-ju
通过向烟气中注入臭氧，先将NO氧化为NO2，再用软锰矿浆同时吸收烟气中的NO2和SO2。对吸收过程中的反应机理和产物进行了探讨。研究了臭氧浓度、NO浓度、软锰矿浓度和反应温度对NOx/SO2去除率和Mn提取率的影响。结果表明，臭氧可以选择性、高效地将NO氧化为NO2，软锰矿浆中的MnO 2在液相中可将SO2氧化为MnSO 4，将NO2氧化为Mn（NO3）（2）。温度、臭氧浓度和NO入口浓度对脱硫效率和锰提取率的影响不大。具体而言，当SO2去除效率下降到90%时，Mn提取率稳定在85%左右。NO去除率随臭氧浓度、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 ℃升高到40 ℃时，NO去除率保持稳定，当烟气温度超过40 ℃时，NO去除率下降。当入口NO浓度为750 ppm，臭氧浓度为900 ppm，软锰矿浓度为500 g/L，温度为25 ℃时，NOx去除率达到82%。(C)2011爱思唯尔有限公司版权所有。
NO was oxidized into NO2 first by injecting ozone into flue gas stream, and then NO2 was absorbed from flue gas simultaneously with SO2 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 NOx/SO2 removal efficiency and Mn extraction rate were also investigated. The results showed that ozone could oxidize NO to NO2 with selectivity and high efficiency, furthermore, MnO2 in pyrolusite slurry could oxidize SO2 and NO2 into MnSO4 and Mn(NO3)(2) in liquid phase, respectively. Temperature and concentrations of injected ozone and inlet NO had little impact on both SO2 removal efficiency and Mn extraction rate. Specifically, Mn extraction rate remained steady at around 85% when SO2 removal efficiency dropped to 90%. NO 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 degrees C to 40 degrees C and decreased when the flue gas temperature exceeded 40 degrees C. NOx 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 degrees C. (C) 2011 Elsevier B.V. All rights reserved.