An experimental investigation on heating rate effect in the thermal behavior of perhydrous bituminous coal during pyrolysis.

Perhydrous bituminous coal has multi-purpose industrial applications established by its distinctive thermal behavior. The Huainan coalfield in China has a large volume of these types of coals. Nevertheless, little information is obtainable with respect to their thermodynamic characteristics. In this study, one representative coal sample, selected from Zhuji Coal Mine, was scrutinized using thermogravimetry/mass spectrometry at different heating rates. The observed results indicate that the process of thermal decomposition of this sample can be partitioned into three evident stages associated with its mass loss rates and the releasing of gaseous species. The secondary pyrolysis step (300-600 °C), in particular, was affected by means of the alterations of heating rate. The maximum mass loss rate and the releasing rate of gaseous species increased related with the increase of heating rate. To achieve reliable kinetic parameters, the Coats-Redfern and Flynn-Wall-Ozawa methods are integrated. The activation energy is applicable in the range of 108-224 kJ mol. [ABSTRACT FROM AUTHOR]