THERMAL SCIENCE

International Scientific Journal

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Luka M. Marinović

,

Dejan M. Mitrović

ANALYSIS OF NOX EMISSION REDUCTION AND CHANGES IN EXERGY BY FLUE GAS RE-CIRCULATION 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 NOx, as the main pollutant during their combustion, is causing more and more research interest. This paper deals with the impact of re-circulation of combustion products on the reduction of NOx emissions, and exergy destruction as its consequence. In the first part of the paper, mechanisms of NOx formation and the factors that affect it are reviewed. After that, a simplified analysis of the flue gases re-circulation 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
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2025, VOLUME 29, ISSUE Issue 5, PAGES [3429 - 3439]
REFERENCES
  1. Zajacs, A., et al., Impact of Flue Gas Re-circulation on the Efficiency of Hot-water Boilers, Construction of Unique Buildings and Structures, 93 (2020), 8, p. 9304
  2. Al Wahedi, F. S. A. A., Dadach, Z., E., Cost Effective Strategies to Reduce CO2 Emissions in the UAE: A Literature Review, J. of Industrial Engineering and Management, 2 (2013), 4, 1000116
  3. Tanasić, N., et al., Effects of Flue Gas Re-circulation on NOx Emission from Gas-Fired Utility Boilers, Current Problems in Experimental and Computational Engineering, Proceedings, International Conference of Experimental and Numerical Investigations and New Technologies, CNNTech 2021, Zlatibor, Serbia, 2021, pp. 319-337
  4. Yue, T., et al., Emission characteristics of NOx, CO, NH3, and VOC from gas-Fired Industrial Boilers Based on Field Measurements in Beijing City, China, Atmospheric Environment, 184 (2018), pp. 1-8
  5. Nikolić, J., et al., Measures and Methods to Reduce Nitrogen Oxide Emissions from Glass Melting Furnaces (in Serbian), Tehnika - Rudarstvo, Geologija i Metalurgija, 62 (2011), 3, pp. 393-398
  6. Gholami, F., et al., Technologies for the Nitrogen Oxides Reduction from Flue Gas: A Review, Science of the Total Environment, 714 (2020), 136712
  7. Turns, T., An Introduction Combustion: Concepts and Applications, 3rd ed., Mc Graw Hill, New York, USA, 2012
  8. Bowman, C., Control of Combustion-generated Nitrogen Oxides Emissions: Technology Driven by Regulation, Proceedings, 24th Symposium (International) on Combustion, the Combustion Institute, Sydney, Australia, 1992, Vol. 24, pp. 859-878
  9. Jerzak, W., Emissions of NOx and CO from Natural Gas Combustion with Adding CO2 at Varying Distances from the Burner, Rocznik Ochrona Srodowiska, 16 (2014), 1, pp. 148-160
  10. Navrodska, R., et al., Reducing Nitrogen Oxide Emissions in Boilers at Moistening of Blowing Air in Heat Recovery Systems, Proceedings, 11th Conference on Interdisciplinary Problems in Environmental Protection and Engineering EKO-DOK 2019, E3 Web of Conferences, Polanica-Zdroj, Poland, 2019, Vol. 100
  11. Pan, D., et al., Effects of Flue Gas Re-Circulation on Self-Ex-Cited Combustion Instability and NOx Emission of a Premixed Flame, Thermal Science and Engineering Progress, 30 (2022), 101252
  12. ***, Internal data of Faculty of Mechanical Engineering of University of Nis
  13. Abdelaal, M., et al., Effect of Flue Gas Re-Circulation on Burner Performance and Emissions, Journal of Al Azhar University Engineering Sector, 11 (2016) 41, pp. 1275-1284
  14. Varga, A., et al., Influence of Flue Gas Re-circulation on NOx and CO Formation, Strojarstvo, 46 (2004), 1-3, pp. 51-55
  15. Cho, S. H., et al., Impact of Flue Gas Re-Circulation Methods on NO Emissions and Flame Stability in a Swirling Methane Burner, Applied Thermal Engineering, 261 (2025), 125139
  16. Nhan, H. K., et al., CFD Investigation of NOx Reduction with a Flue-Gas Internal Re-Circulation Burner in a Mid-Sized Boiler, Journal of Mechanical Science and Technology, 33 (2019), 6, pp. 2967-2978
  17. Zajemska, M., et al., The Kinetics of Nitrogen Oxides Formation in the Flame Gas, Economic and Environmental Studies, 15 (2015), 4, pp. 445-460
  18. ***, CIBSE Journal, www.cibsejournal.com/cpd/modules/2016-12-nox/
  19. Đurić, V, Parni Kotlovi - Sveska 1, Teorijske Osnove, (Steam Boilers - Vol. 1, Theoretic Fundamentals - in Serbian), Građevinska knjiga, Belgrade, SFR Yugoslavia, 1969
  20. Cengel, Y., Bolen, M., Thermodynamics: An Engineering Approach, 8ht ed., Mc Graw Hill, New York, USA, 2015
  21. Smiljanić, M., et al., The Problem of Loss Determination of Technical Work of Exit Gases in a Boiler Stack - Contribution the Solution (in Serbian), Termotehnika, 42 (2016), 1, pp. 99-111
  22. Brkic, Lj., et al,., Termički Proračun Parnih Kotlova, (Thermal Calculation of Steam Boilers - in Serbian), Faculty of Mechanical engineering of University of Belgrade, Belgrade, Serbia, 2015
  23. Mitić, D., Mihajlović, E., Metode izračunavanja temperature sagorevanja, (Methods for combustion temperature calculation - in Serbian), Faculty of Occupational Safety of University of Niš, Niš, SR Yugosla­via, 2000
  24. House, E. J., Chemical Kinetics, 2nd ed., Academic Press, London, UK, 2007
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Analysis of NOx emission reduction and changes in exergy by flue gas re-circulation during natural gas combustion

2025 Society of Thermal Engineers of Serbia. Published by the Vinča Institute of Nuclear Sciences, National Institute of the Republic of Serbia, Belgrade, Serbia. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International licence