Change in electric and dielectric properties of some Australian coals during the processes of pyrolysis

The investigation of change in electric and dielectric properties of Australian coals was carried out during their pyrolysis. The relation between the increase of the tangent of dielectric losses and electrical resistivity in the pre-plastic state of pyrolysis was established. It was shown that at the pre-plastic stage of pyrolysis, when the organic coal mass is in the glassy state, the decrease in value of electrical resistivity is caused by the increase in rotational movement of segments of macromolecules as evidenced by the increase in tgδ parameter. The character of change in curves ρ = f(T°) and tgδ = φ(T °C) in the pre-plastic state of the process of coal pyrolysis predetermines the values of parameters of coke durability.