NOx Removal from Flue Gas Using an Ozone Advanced Oxidation Process with Injection of Low Concentration of Ethanol: Performance and Mechanism
NOx Removal from Flue Gas Using an Ozone Advanced Oxidation Process with Injection of Low Concentration of Ethanol: Performance and Mechanism
复制标题
使用注入低浓度乙醇的臭氧高级氧化工艺去除烟气中的氮氧化物：性能和机理
DOI：
10.1021/acs.energyfuels.9b03839
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发表时间：
2020-02-01
期刊：
影响因子：
5.3
通讯作者：
Pan, Xinxing
中科院分区：
文献类型：
--
作者：
Han, Zhitao;Wang, Junming;Pan, Xinxing
基于放大反应系统，研究了乙醇喷射对臭氧高级氧化工艺中NOx去除性能的影响。实验结果表明，在模拟烟气中引入乙醇可以大大提高O-3-乙醇-NOx系统的NOx去除性能。当 150 摄氏度时烟气中 NO 初始浓度为 400 ppm 时，注入 200 ppm O(3 ) 可以将大约一半的 NO 氧化成 NO2。当烟气中进一步引入-150 ppm乙醇蒸气时，出口NO浓度将急剧下降至68 ppm左右，同时出口NO2浓度将下降至165 ppm左右。这种增强效果归因于O-3、乙醇和NOx在气相中的协同反应。采用气相色谱-质谱联用技术对气体反应产物进行分析，发现亚硝基甲烷、硝基甲烷、硝酸甲酯、硝酸乙酯等硝基化合物。这表明，在NOx存在下，乙醇和O-3之间可能会发生一些复杂的反应，产生大量的有机自由基和羟基自由基。此外，通过比较O-3-NOx和O-3-乙醇-NOx体系中NQ浓度的变化，研究了关键运行参数对NOx去除性能的影响，并讨论了相关的反应机理。
Effects of ethanol injection on NOx removal performance in an ozone advanced oxidation process were investigated based on a scale-up reaction system. Experimental results showed that the introduction of ethanol in simulated flue gas could enhance NOx removal performance greatly in the O-3-ethanol-NOx system. With an initial NO concentration of 400 ppm in flue gas at 150 degrees C, the injection of 200 ppm O(3 )could oxidize approximately half of NO into NO2. When further introducing -150 ppm ethanol vapor in flue gas, the outlet NO concentration would drop sharply to similar to 68 ppm while outlet NO2 concentration would drop down to similar to 165 ppm at the same time. This enhancement effect was ascribed to a synergistic reaction between O-3, ethanol, and NOx in the gas phase. The gas reaction products were analyzed by using gas chromatography-mass spectrometry, and some kinds of nitro-compounds, such as nitroso methane, nitromethane, nitric acid methyl ester, and nitric acid ethyl ester, had been found. It is implied that some complex reactions might occur between ethanol and O-3 at the presence of NOx in which a large number of organic radicals and hydroxyl radicals had been produced. In addition, the effects of key operating parameters on NOx removal performance were investigated through comparing the changes in the NQ concentration between O-3-NOx and O-3-ethanol-NOx systems, and the related reaction mechanism had also been discussed.