Swelling and plastic properties of coal devolatilized at elevated pressures: an examination of the influences of coal type

Abstract

Attempts have been made to correlate the measured thermoplastic properties of 24 coals (hvCb to Ivb) pyrolysed at elevated pressures (0.1 to 2.9 MPa) with some commonly reported characterization parameters. While the thermoplastic transition temperatures can be correlated somewhat with some coal properties (e.g., vitrinite mean-maximum reflectance, or carbon content), the maximum swelling parameter of these coals, especially at elevated pressures, shows little correlation with the usual coal characteristics which are measured at atmospheric pressure (e.g., ASTM FSI or vitrinite reflectance). In general, the behaviour of the coals at elevated pressures cannot be predicted from their properties obtained at atmospheric pressure. These data stress the importance and profound influence of elevated pressure on swelling and plastic properties of coals. All thermplastic properties were measured by a high-pressure microdilatometer. © 1986.