Effect of partial rapid pyrolysis on bituminous properties: From structure to reactivity

In this paper, a typical Chinese bituminous coal was pyrolyzed rapidly and repeatedly in a high frequency furnace at 1000 °C, to investigate the changes of coal physicochemical structures, reactivities and their relationship. The physicochemical structure was mainly characterized by Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, pore analysis, etc. The results showed that after the rapid pyrolysis, the specific surface area was reduced significantly, the average particle size and the content of amorphous carbon structure increased first and then decreased, the content of oxygen-containing group exposed to the surface decreased and the aromaticity increased gradually. The reactivities were analyzed by thermogravimetric analysis (TGA), including slow pyrolysis (from 105 to 1000 °C) and in-situ gasification (at 850, 900, 950 and 1000 °C). For slow pyrolysis, the primary decomposition peak of pretreated samples was inhibited while the secondary peak was enhanced. For in-situ gasification,...