SINOPSIS

An oxygen-blown pulverized coal burner for utilization of various kinds of coal was newly proposed and developed. The combustion efficiency of 99.7% was achieved by the moderate swirl burner. The flame stabilization could not be realized by the strong swirl burner, and the content of unburned carbon in ash was more than that of the moderate swirl burner experiment. The distribution of vorticity in the moderate swirling flow was equally proportioned even though the flow ratio was changed between 0.15 and 0.88. Additionally, the state of untidiness was observed near the central part of the burner nozzle in the strong swirling flow. The close relationship between combustion efficiency and vorticity profiles was found by PIV analysis of the flow. The moderate swirl burner was suitable for designing the burner structure in oxygen-blown pulverized coal combustion.