On the oxygen-enriched combustion of a single coal char particle

• Autorzy: Lewtak, R. , Milewska, A.
• Języki publikacji: EN

Abstrakty

EN

The paper presents numerical results of single coal char particle combustion in the oxygen-enriched environment at which the effect of the equimolar and non-equimolar counterdiffusion has been taken into consideration. Usually, the phenomenon of the non-equimolar counterdiffusion arising at combustion of char particles is neglected and superseded by the equimolar counterdiffusion. Such a replacement can lead to results, e.g. profiles of particle temperature and species concentrations, which do not agree with the real process. First, the phenomenon of the equimolar and non-equimolar counterdiffusion for a single spherical particle is explained in detail. Next, the governing equations of single char particle combustion are presented. Finally, numerical simulations have been performed at O2 mole fractions of 26%, 36% and 46% for the particle size of dp = 160 μm and gas temperature of 1373 K. Numerical results, e.g. profiles of char burnout, temperature, molar fractions at the particle surface, show the significant influence of the non-equimolar counterdiffusion on the combustion.

Słowa kluczowe

EN

non-equimolar counterdiffusion; oxygen-enriched combustion; char particle combustion

• Czasopismo: Archivum Combustionis
• Rocznik: 2015
• Tom: Vol. 35 nr 1
• Strony: 21--28
• Opis fizyczny: Bibliogr. 17 poz., rys., tab.

Twórcy

autor

Lewtak, R.

• Department of Thermal Processes Institute of Power Engineering Augustowka 36, 02-981 Warsaw, Poland,

autor

Milewska, A.

• Department of Thermal Processes Institute of Power Engineering Augustowka 36, 02-981 Warsaw, Poland

Bibliografia

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