무탄소 암모니아 다단연소 특성 연구

Abstract

This study explores the staged combustion characteristics of ammonia(NH3), a zero-carbon fuel and hydrogen carrier, in comparison with methane(CH4), using numerical simulations conducted with the ANSYS CHEMKIN-Pro reactor network model. Ammonia fuel requires effective strategies to mitigate nitrogen oxide(NOx) emissions. The study investigates four combustor configurations, each featuring different primary and secondary zone designs, to assess the effectiveness of staged combustion—combining rich premixed and air-diluted stages—in reducing fuel NOx formation. Key parameters such as primary zone equivalence ratio, operating pressure, co-firing effects, and residence time(linked to primary zone length) are analyzed. The results show that residence time in the primary zone plays a critical role in governing NOx emissions. While methane combustion primarily generates thermal NOx, ammonia combustion leads to the formation of fuel NOx, with co-firing scenarios exhibiting intermediate emissions. The findings highlight the potential of optimizing staged combustion configurations and primary zone parameters to significantly reduce NOx emissions, advancing ammonia’s viability as a sustainable fuel. These insights provide essential guidelines for the design of efficient, low-emission ammonia-based combustion systems.