Effect of heat transfer on tar and light gases from coal pyrolysis

This report presents the results of a study of coal pyrolysis in three different reactors covering a wide range of heating conditions. The specific purpose of the investigation was to determine if the rate of heat delivery to a high volatile bituminous coal during the tar formation and evolution phase has a significant effect on the tar yields and molecular weight distribution for a high volatile bituminous coal. From the point of view of understanding coal devolatilization and the development of fundamental kinetic models, the investigation is geared to determining whether the same tar formation and evolution processes are occurring in widely different regimes of heat transfer rate and modes of heat transfer. The heavy hydrocarbons yields and chemical characteristics provide a type of observable monitor, to generate a microscopic model of the devolatilization/pyrolysis process.