This paper proposes two-stage O3 oxidation combined with Ca(OH)2 for simultaneous removal of NOx and SO2 (NOx: Nitrogen oxides including NO, NO2 and N2O5). In two-stage oxidation, NO was first oxidized to NO2 in an oxidation tube, and NO2 was further oxidized into N2O5 in the spray tower. NOx and SO2 were simultaneously removed in the spray tower. This method can effectively reduce the extra waste of O3 caused by the decomposition of N2O5, especially at high temperature. Effects of various factors on denitrification efficiency were investigated. The results showed that the NOx removal efficiency decreased and O3 extra consumption ratio increased with the increase of oxidation temperature or oxidation reaction time. When the O3/NO molar ratio was 1.8, one-stage O3 oxidation at 150 oC extra wasted 33.3% of O3. With the increase of O3 concentration at site 2, the NOx removal efficiency first increased and then stabilized. Compared with the one-stage O3 oxidation-absorption, the two-stage oxidation-absorption improved NOx removal efficiency from 62.5% to 89%. In addition, the increase of CaSO3 slurry concentration had little effect on the denitrification efficiency.

中文翻译：

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使用两级 O3 氧化结合 Ca(OH)2 吸收同时去除 NOx 和 SO2

本文提出了与 Ca(OH)2 相结合的两阶段 O3 氧化，用于同时去除 NOx 和 SO2（NOx：氮氧化物，包括 NO、NO2 和 N2O5）​​。在两段氧化中，NO首先在氧化管中被氧化成NO2，NO2在喷淋塔中进一步被氧化成N2O5。NOx 和 SO2 在喷淋塔中同时被去除。这种方法可以有效减少N2O5分解引起的O3的额外浪费，特别是在高温下。研究了各种因素对反硝化效率的影响。结果表明，随着氧化温度或氧化反应时间的增加，NOx去除效率降低，O3额外消耗率增加。当 O3/NO 摩尔比为 1.8 时，150 oC 的一级 O3 氧化额外浪费了 33.3% 的 O3。随着站点 2 O3 浓度的增加，NOx 去除效率先增加后趋于稳定。与一级O3氧化吸收相比，二级氧化吸收将NOx去除效率从62.5%提高到89%。此外，CaSO3浆液浓度的增加对反硝化效率影响不大。