Abstract: The differentiation patterns of pulverized-coal minerals into fly ash and bottom ash in power plant boilers were investigated using heavy liquid float-sink separation. By separating the pulverized coal, fly ash, and bottom ash into density fractions of 1.3-2.4 g/cm³, X-ray diffraction (XRD), X-ray fluorescence (XRF), and scanning electron microscopy (SEM) were used to analyze the composition and morphology of each density sub sample, and the generation of liquid phase at different temperatures was calculated. Results show that pulverized-coal particle density is ≥1.3 g/cm³, and the yield of particles with density of 1.5-<1.8 g/cm³ is as high as 40.3%. The density of fly ash is concentrated at ≥1.7 g/cm³, with a density component content of up to 37.7% for densities ≥2.4 g/cm³. Bottom ash particles lies mostly in 2.1-<2.4 g/cm³. In boilers, coal minerals first form varying-sized ash particles based on their states, where particles below 10 μm become fly ash, those above 50 μm settle as bottom ash, and those between 10 and 50 μm may collide. Fusible ones in this intermediate size range coalesce and grow into bottom ash.