Abstract To explain the role of alkali metal in N2O and NO emission during Zhundong coals oxy-fuel circulating fluidized bed combustion, the influences of alkali metals on the fuel-N and recycled-N were investigated in the present work. Results were obtained based on the experiments performed on a 50 kW oxy-fuel circulating fluidized bed combustor system. First, the N2O and NO emission characteristics during high-sodium Zhundong coals oxy-fuel combustion were obtained. Though the emission characteristics varied with coal types due to the different coal properties, it can be concluded that high-sodium coal can achieve low N2O concentration. High inlet oxygen concentration was conducive to the decrease of N2O and NO concentrations. The simulated recycled SO2 can enhance the reduction of NO. Then, the influences of alkali metals on the fuel-N and recycled-N were identified via injecting NaCl/Na2SO4 during low-sodium coal combustion. Both NaCl and Na2SO4 can decrease CO and N2O concentrations but increase NO concentration. While there hardly exist any interactions between NaCl/Na2SO4 and simulated recycled NO.

中文翻译：

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高钠准东煤富氧循环流化床燃烧过程中碱金属对N2O和NO排放的影响

摘要 为了解释碱金属在准东煤富氧循环流化床燃烧过程中N2O和NO排放中的作用，本文研究了碱金属对燃料-N和再生-N的影响。结果是基于在 50 kW 氧燃料循环流化床燃烧器系统上进行的实验获得的。首先，获得了高钠准东煤富氧燃烧过程中N2O和NO的排放特征。尽管由于煤的性质不同，煤种的排放特征有所不同，但可以得出结论，高钠煤可以实现低 N2O 浓度。高入口氧浓度有利于降低 N2O 和 NO 浓度。模拟回收的 SO2 可以增强 NO 的还原。然后，通过在低钠煤燃烧过程中注入 NaCl/Na2SO4 来确定碱金属对燃料 N 和再生 N 的影响。NaCl 和 Na2SO4 都可以降低 CO 和 N2O 的浓度，但会增加 NO 的浓度。而 NaCl/Na2SO4 和模拟循环 NO 之间几乎不存在任何相互作用。