The role of alkali metal in N2O and NO emission during high-sodium Zhundong coals oxy-fuel circulating fluidized bed combustion. (1st November 2020)

• Record Type: Journal Article
• Authors: Li, Wei; Liu, Dianbin; Li, Shiyuan; Kong, Runjuan; Ding, Hongliang
• Is Part Of: Fuel. Volume 279(2020)
• Publication Date: 2020-11-01
• Subjects: Oxy-fuel combustion -- Circulating fluidized bed -- Alkali metals -- N2O and NO emission; Fuel -- Periodicals; Coal -- Periodicals; Coal; Fuel; Periodicals; 662.6
• DOI: 10.1016/j.fuel.2020.118443
• Languages: English
• ISSNs: 0016-2361

Abstract

Abstract: To explain the role of alkali metal in N2 O 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 N2 O 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 N2 O concentration. High inlet oxygen concentration was conducive to the decrease of N2 O 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/Na2 SO4 during low-sodium coal combustion. Both NaCl and Na2 SO4 can decrease CO and N2 O concentrations but increase NO concentration. While there hardly exist any interactions between NaCl/Na2 SO4 and simulated recycled NO.