Effect of Fe on NO release during char combustion in air and O₂/CO₂

Abstract

The chemistry of char was probed by studying nitrogen release under the reactions with air and oxy-fuel combustion. The experiments were conducted in a drop tube furnace and a fixed bed flow reactor. NO was observed during those experiments. The results show that the particle size of char generated at 1073 K in CO₂ is larger than that in N₂. However, at 1573 K, it is smaller in CO₂ atmosphere due to particle breaking by gasification of char and CO₂. The Fe addition increases the NO conversion ratio, and the effect of Fe rises steeply with the process going until it becomes stable in the end. The results also indicate that the release of NO increases more significantly with the Fe addition in oxy-fuel environment.

Keywords

NO / Fe / char / combustion / CO₂

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Higher Education Press and Springer-Verlag Berlin Heidelberg