Abstract:

Peat smoldering is one of the main combustion modes of forest ground fires. Research into the pyrolysis kinetics of peat is an essential step in studying the peat smoldering mechanism and ground fire behavior. We measured the elemental composition of one typical peat sampled from the northeast forest zone of China by means of spectrofluorometry and studied the pyrolysis characteristics of peat with thermogravimetry-differential thermal analysis (TG-DTA). Results show that the peat sample is composed of more than 45 elements. The pyrolysis process of peat may be divided into three stages, i.e., dehydration, organic matter pyrolysis and mineral decomposition. Because organic matter pyrolysis played an important role in peat smoldering, the pyrolysis kinetics of organic matter was determined. Using thermal kinetic analysis theory and optimization methods, the model that three-component react parallelly was established to describe the scheme of peat pyrolysis. We found that the scheme containing three-parallel-reactions could describe the pyrolysis kinetics very well.

Key words: Pyrolysis, Peat, Ground fire, Kinetic model, Thermogravimetry-differential thermal analysis