Study on removing NO from simulated marine diesel engine exhaust gas using the novel composite system of Ozone-Na2SO3/(NH2)2CO
Study on removing NO from simulated marine diesel engine exhaust gas using the novel composite system of Ozone-Na2SO3/(NH2)2CO
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DOI：
10.1016/j.cej.2021.132707
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发表时间：
2022-02
影响因子：
15.1
通讯作者：
Zhao Zhang;Song Zhou;Hongyuan Xi;Weijian Zhou
中科院分区：
文献类型：
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作者：
Zhao Zhang;Song Zhou;Hongyuan Xi;Weijian Zhou
船舶废气中的污染物严重威胁大气质量和人体健康。湿吸收是控制NOx最有效的途径之一。严格的排放控制法规要求湿式NOx控制技术具有较高的NOx去除效率，吸收液的硝酸盐浓度低于60 mg/L。臭氧-Na 2SO 3/（NH 2）2CO新体系不仅能使NOx吸收效率和硝酸盐残留量完全符合规定，而且能有效降低（NH 2）2CO消耗量和亚硝酸盐浓度。NO的最终产物主要是N2而不是硝酸盐。考察了O3浓度、Na 2SO 3浓度、（NH 2）2CO浓度、O2浓度、SO2浓度、初始pH值、温度等因素的影响。实验结果表明，O3浓度、Na 2SO 3浓度和初始pH值是影响NOx去除率的主要因素。硝酸盐浓度主要受Na 2SO 3浓度和初始pH值的控制。而亚硝酸盐浓度则受（NH 2）2CO浓度和初始pH值的影响。O_3浓度和Na_2SO_3浓度的增加促进了NO_x的吸收。初始pH值的降低虽然导致硝酸盐含量略有增加，但大大降低了亚硝酸盐的含量。此外，Na 2SO 3浓度的增加有助于提高脱氮效率，抑制硝酸盐的生成。初始pH值是NO吸收过程的关键参数。O_3-Na_2SO_3/（NH_2）_2CO复合体系在海洋湿态NOx控制技术领域显示出巨大的应用潜力。
The pollutants from the marine exhaust gas seriously threaten air quality and human health. Wet absorption is one of the most efficient NOxcontrol pathways. The strict emission control regulations require the wet NOxcontrol technology to have high NOxremoval efficiency and the nitrate concentration of the absorption solution to be below 60 mg/L. The novel system of ozone-Na2SO3/(NH2)2CO could not only make the NOxabsorption efficiency and the amount of nitrate residue fully meet the regulations but also effectively reduce the (NH2)2CO consumption and the nitrite concentration. The final product of NO was mainly N2instead of nitrate. The effects of O3concentration, Na2SO3concentration, (NH2)2CO concentration, O2concentration, SO2concentration, initial pH value, and temperature were thoroughly investigated. The experimental results showed that the NOxremoval efficiency was mostly influenced by the O3concentration, Na2SO3concentration, and the initial pH value. Moreover, the nitrate concentration was mainly controlled by Na2SO3concentration and initial pH value. While the nitrite concentration was governed by the (NH2)2CO concentration and initial pH value. The increase of O3concentration and Na2SO3concentration promote NOxabsorption. Although the decrease of initial pH value resulted in a slight increase of nitrate, it greatly reduced the content of nitrite. Furthermore, the increase of Na2SO3concentration helped to improve the NOxremoval efficiency and inhibited the generation of nitrate. Initial pH value was the critical parameter for the NO absorption process. Ozone-Na2SO3/(NH2)2CO composite system showed great application potential in the field of marine wet NOxcontrol technology.