Direct Observation of a Single Coal Particle Combustion in a Laminar Flow Furnace

The experiment on a single coal particle combustion was carried out with a laminar flow furnace to clarify the fundamental combustion mechanism of pulverized coal particles injected into the blast furnace. High speed camera was used to observe the coal particle combustion, and the temperature distribution nearby the coal particle was estimated by the image analyzer. A flame sheet around the particle due to the combustion of volatile matter was observed after the ignition, and it was found that the radius of flame was dependent on the oxygen concentration and coal type. On the basis of these results, it was estimated that the location of the flame sheet of coal particle influenced on the combustion rate through the heat supply from the combustion flame of volatile matter. Moreover, in the case of massive coal injection in a blast furnace, the dispersion of coal particles and the oxygen content nearby the coal particles were considered to be significant on the combustion rate.