循环流化床燃煤过程NOx和N2O产生-控制研究进展

循环流化床(CFB)燃烧技术因其燃料适应范围广、污染物排放低等优点，近几十年得到广泛应用. 随着当前环保要求的日益提高，CFB燃煤过程N2O排放浓度较高成为其应用的瓶颈问题. 因此系统总结CFB燃煤过程中NOx和N2O排放的研究现状对开发新型CFB燃煤技术具有重要意义. 本工作首先讨论了CFB燃煤过程中NOx和N2O的均相和异相反应机理，然后应用这些机理分析了床温、过剩空气系数、分级燃烧，以及煤种对CFB燃煤过程NOx和N2O排放的影响. 在此基础上，对常见的抑制NOx和N2O排放的工艺从机理角度进行了归纳总结. 最后，对2种本工作认为有应用前景的CFB燃煤减排NOx和N2O新技术?反向分级燃烧技术及CFB解耦燃烧技术进行了简要论述.

Investigation Progress on Release and Control of NOx and N2O during Coal Combustion in Circulating Fluidized Bed Combustor

Circulating fluidized bed (CFB) coal combustion technology has been extensively applied in the past two decades due to its advantages, such as the adaptability to wide range of coal and low pollution emissions compared with other traditional coal combustion technologies. However, high N2O emission is a prominent disadvantage of CFB coal combustion. As the emission limits become more restrict in recent years all over the world, further lowering pollutant emissions in coal-fired CFB combustor is urgently needed. For this purpose, reviewing available knowledge on the emissions, especially NOx and N2O, in coal-fired CFB combustor is of essential importance. The mechanisms of formation and destruction of NOx and N2O homogeneously and heterogeneously in coal-fired CFB combustor were summarized in this work. The influences of operation parameters of coal-fired CFB combustor, such as bed temperature, excess air number, air staging and coal characteristics, on NOx and N2O emissions were discussed. Some common applied technologies of reducing NOx and N2O emissions in coal-fired combustor were also introduced. Two kinds of promising technologies, named as reversed air staging and CFB decoupling combustion were briefly described.