Nitrogen in coal as a source of nitrogen oxide emission from furnaces

In this paper are presented some experimental results on the conversion of fuel-nitrogen to nitric oxide in both diffusion and premixed flames, and the results are used to speculate on mechanisms of nitric oxide formation. Models of pulverized-coal combustion are reviewed and used to examine the conditions under which fuel-nitrogen contributes significantly to nitric oxide emission. Mechanisms are suggested to explain why fuel-nitrogen contributes most of the emission from fluidized-bed combustors but only a small fraction of the emission from pulverized-coal flames.