Impact of oxygen and nitrogen-containing species on performance of NO removal by coal pyrolysis gas

Coal pyrolysis gas is considered a promising reburn fuel with excellent NO reduction performance because of the present of nitrogen-containing species (HCN and NH3) in the pyrolysis gas. In this study, we explored the effects of oxygen and nitrogen-containing species on NO removal performance with HCN and NH3 by reactive force field (ReaxFF) molecular dynamics (MD) simulations. Results indicate that appropriately reducing O2 concentrations and increasing the amount of nitrogen-containing species can benefit the NO reduction performance by coal pyrolysis gas. In addition, the effects of oxygen and nitrogen-containing species content on the NO removal and mechanisms of NO consumption and N2 formation are illustrated during NO reduction with HCN and NH3, respectively. Finally, based on the simulations results, practical operating strategies are proposed to optimize the NO reduction efficiency. In summary, this study provides new insights into NO reduction performance, which may contribute to optimizing the operating parameters to decrease NOx emissions during coal combustion.