Abstract
The state of carbonaceous components in coal fly ash fractionated by particle size and density was investigated by means of simultaneous thermal analysis-mass spectrometry in an inert atmosphere (He) and a quasi air atmosphere (O2/He=20/ 80vol%). The carbonaceous components were characterized by their thermal degradation behavior and evolved gas species observed in each condition. Their components were proved to exist in three different states: the fractions with larger particle size (>20μm) and medium density (2.0-2.4g/cm3) mostly consist of elemental carbon, the smaller particle size fractions (<5μm) organic and elemental carbon, and the higher density fractions (2.8-3.2g/cm3) carbonate. In addition to the carbonaceous components, the existence of sulfate and hydroxide was suggested.
