| The air pollution is becoming more and more serious in China, especially for NOx. Therefore, it is necessary to develop an economic and efficient denitration technology. In this paper, the systematic research of NOx liquid-phase oxidation and NOx gas-phase oxidation has been carried out. Then the reaction mechanism was proposed, a reasonable route was developed, and the removal efficiency of NO in pilot plant was tested. These studies provided the theoretical and experimental foundation for the industrial application of wet denitration technology.Firstly, experiments on DeNOx were conducted in a lab-scale bubbling reactor with NaCIO as the oxidant and absorbent. The main factors influencing NO conversion efficiency was studied, and the reaction mechanism of simultaneous removal of NO and SO2 by NaCIO was proposed. It was indicated that the initial pH value had a significant influence on the denitrification process. The NO conversion efficiency increased with the increasing of NaCIO concentration and inlet NO concentration. When the aqueous temperature was higher than 60℃, it was not beneficial for the removal of NO. The best absorption efficiency of the individual DeNOx experiments was 43.24% among the experiments. The results of the combined DeSOx\DeNOx experiments showed that SO2 could improve the absorption of NO2. The best DeNOx and DeSOx efficiencies could reach to 53.03% and 100%, respectively.Secondly, the lab-scale ozone oxidation-liquid absorption researches were conducted, the main influence factors for ozone oxidation and liquid absorption were studied. The results showed that NO could be oxidized by ozone. The existence of SO2 had little influence on ozone oxidation. However, it could improve the absorption of NOx. Anyway Ca(OH)2 had been selected as the best absorbent.Finally, pilot study was carried out (2000m3/h actual flue gas). After a continuous operation for 36 hours, it was found that the operation of gas-phase oxidation & liquid-phase absorption process was stable.
|
PDF Full Text Request