THERMAL SCIENCE

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Luka M. Marinović

,

Dejan M. Mitrović

online first only

Analysis of nitrogen oxides emission reduction and changes in exergy by flue gas recirculation during natural gas combustion

ABSTRACT
With the development of the economy and society in the world, fuel consumption has increased, and thus the emission of pollutants into the environment. Since gaseous fuels represent the most environmentally friendly type of fossil fuel, the emission of nitrogen oxides, as the main pollutant during their combustion, is causing more and more research interest. This paper deals with the impact of recirculation of combustion products on the reduction of nitrogen oxide emissions, and exergy destruction as its consequence. In the first part of the paper, mechanisms of nitrogen oxides formation and the factors that affect it are reviewed. After that, a simplified analysis of the flue gases recirculation was performed especially its influence on emission reduction and exergy losses in flue gases stream. The results are discussed in last part of the paper. Presented results can be very useful for quick emission calculations in process of designing natural gas boiler plants.
KEYWORDS
nitrogen oxides, emission reduction, combustion, flue gases recirculation, Zeldovich mechanism, natural gas, exergy
PAPER SUBMITTED: 2025-12-18
PAPER REVISED: 2025-02-18
PAPER ACCEPTED: 2025-02-21
PUBLISHED ONLINE: 2025-04-05
DOI REFERENCE: https://doi.org/10.2298/TSCI241218054M
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Analysis of nitrogen oxides emission reduction and changes in exergy by flue gas recirculation during natural gas combustion