O_3氧化-SO_3^(2-)还原燃煤烟气脱硝

Flue-gas De-NO_x technology with O_3 oxidation-SO_3^(2-) reduction process

燃煤烟气同时脱硫脱硝是燃煤烟气污染治理技术研究与应用的趋势。提出利用臭氧注入到模拟烟气氧化NO生成NO_2,再利用NO_2氧化亚硫酸盐生成硫酸盐,同时NO_2被还原生成N2的工艺方法。研究了沿面放电法产生臭氧、臭氧氧化NO、NO_2在亚硫酸钠溶液中的转化和溶液中SO_2-4生成及影响因素。结果表明,臭氧投加量对NO氧化过程影响较大,当O_3/NO摩尔比为1.1时,烟气中NO脱除率达到90%;亚硫酸钠溶液中NO_2脱除率达到97%,且在吸收液温度小于80℃、pH小于10的条件下,NO_2脱除率基本保持不变;液相亚硫酸钠溶液中NO_2与SO_2-3离子之间氧化还原反应生成SO_2-4离子和N2是NO_2转化的主导反应。

Simultaneous desulfurization and denitrification of flue gas is a trend in the research and application for the pollution control technology. In this paper,we conduct the experiments according to the following thoughts. First,we ensure that the NO in flue gas oxidized to NO2 by ozone injection. Then we use sulfite solution as the absorbent to analysis the absorption process. It was found that the removal efficiency of NO increased with the molar ratio ofO3/NO becoming higher,and when the molar ratio was 1. 1,the removal efficiency of NO reached 90%. During the absorption process,the removal efficiency of NO2 reached 97% and remained unchanged under the condition of less than 80 ℃ in temperature and 10 in pH value. By analyzing the production of the absorption process,we can know that the redox reaction between NO2 and SO3^2-was the main reaction in De-NOxprocess. The mainly production in the mixture solution of Na2SO3 and NaOH after the absorption process were SO4^2- and N2.