Visible flames of pulverized coal particles in a semi-quiescent environment were investigated using an optical multi-channel analyzer. In a rapid heating situation, coal particles are observed with their accompanying volatile cloud where pyrolyzed material stays abjacent to the particle forming a nearly concentrical mantle. Radiative emissions from the particle flames were recorded for the wavelength region of 400 to 850 nm. The spectrum were interpreted in terms of optical temperature and relative total radiation energy rate by fitting to the planck's blackbody distribution function. The temperature of the paticle flames exceeded that of the surrounding gas over 200℃ - 800℃, depending on the combustion condition and coal types. The temperature and relative total radiation energy rate of the particle flames increased with the increase of residual oxygen density. By classifying the spectral patterns recorded at different reaction residence times, a plausibly hypothetical time history patterns of particle flames were proposed. This sequential represents suggested that the maximum temperature point and the maximum radiation energy rate point do not coincide. That is, the flame radiation energy rate reaches its peak when the flame temperature decreased after reaching its maximum. Line emissions of Na were discussed along with the presence of the atoms near the observed flames. It was observed that there were the differences in the line emission of each coal types.
