Effects of Heating Rate, Particle Size, Aerobic Atmosphere, and Flow Rate on the Pyrolysis Characteristics of Huadian Oil Shale

To master the pyrolysis characteristics of oil shale under diverse conditions, we analyzed Huadian oil shale by TG-DTA, FT-IR, and XRD, and compared the effects of heating rate, gas flow rate, pyrolysis atmosphere, and particle size on its pyrolysis behavior. The results show that when the heating rate increases from 5 to 15°C/min, the corresponding temperature increases from 439.1 to 461.6°C, and the mass loss rate increases from 12.42% to 13.51%. When the particle size increased from 0.075 to 0.355 mm, the maximum mass loss rate temperature, termination temperature, and mass loss rate increased, but the initial temperature decreased from 336.1 to 275.8°C. When the oxygen concentration increased from 10 to 30%, the initial temperature, maximum mass loss rate temperature, and termination temperature decreased with the increase of oxygen concentration, but the mass loss rate increased from 17.25 to 17.69%, as well as when the gas flow rate increased from 30 to 100 mL/min, the termination temperature and mass loss rate increased, but the initial temperature decreased from 366.5 to 303.9°C. The Coats-Redfern method was used to calculate the pyrolysis kinetics parameters at different heating rates and different particle sizes. The results show the activation energy increases with increasing heating rates while decreasing with increasing particle sizes. This study is of great significance in optimizing the thermal conversion process of Huadian oil shale as raw material.