Pyrolysis mechanism and kinetic model of Mudanjiang oil shale in the Songliao Basin, China

Abstract

In recent years, a lot of work on the development of oil shale has been done with regard to the Chinese oil shales. However, the research is mainly with respect to the processing aspects of oil shale. The pyrolysis mechanism of oil shale has been limited, to some extent, by instrumentation and analytical techniques. In this paper, pyrolysis kinetics characteristics of oil shale samples obtained from Mudanjiang were investigated by Rock-Eval analysis. The weight loss data, pyrolysis mechanism, and properties of oil shale were analyzed at different heating rates (10, 15, 20, 25, 30 C/min) in the temperature range from 200 to 600 C. In this paper, a distribution function of apparent activation energy and a relationship equation of apparent energy with frequency factor have been obtained. A special kinetic model was developed, fully suitable for the pyrolysis characteristics of oil shale. This model was also verified by experiment. Throughout the analysis of pyrolysis kinetics, it was observed that the pyrolysis reaction mechanism at different temperatures could be explained. The results may provide the theoretical basis for further effective and economical exploitation of oil shale.