Thermal Properties And Rotary Kiln Retorting Experiment Of Oil Shale Particles

With the growth of human population and rapid development of social economy, human are demanding more and more energy. However, unrenewable resources, such as coal, petroleum and natural gas are becoming less and less. Therefore, Looking for alternative energy sources has become a pressing matter of the moment, which is related to human’s survival and development. Oil shale has a huge reserves and it can be seen as an alternative energy resource. In order for the development and operation of the comprehensive utilization system for oil shale, the thermal properties and rotary kiln retorting experiments of oil shale particles were performed.Using simultaneous differential scanning calorimetry(DSC) and thermogravimetric analysis(TGA), non-isothermal pyrolysis experiments were carried out to analyze and compare two types of oil shale from the northeast of China at temperatures ranging from 40 to 850 oC. The weightlessness characteristics, endothermic law and kinetics parameters of oil shale in three pyrolysis stages were studied. Specific heat capacities of two oil-shale semicokes were measured below 500 oC by DSC method, showing that specific heat capacity of semicoke will increase with the increase of the temperature, and carbonization of kerogen can bring about a further positive effect on it.In addition, based on the platy structure of oil shale particles, mathematical heat transfer model was developed to analyze the heat transfer history within oil shale particle in the process of the retorting, incorporating the pyrolytic heat as an internal heat sink. Furthermore, the central temperature history and heating time of Gonglangtou oil shale particles with different sizes are predicted at various heating rates using this heat transfer model, showing that platy structure characteristic offers an important role for the heat transfer process and even for the particle fragmentation.Lastly, rotary kiln retorting experiments were performed in cold and hot state to deal with small-size oil shales. The experiments explored the effects of different sizes quartz sands on the retorting process. Compared the quality and yield of shale oil under two different conditions, it can be seen that the quality and yield of shale oil is better under the large size quartz sands than small size quartz sands. In the process, a lot of practical problems were solved to improve the rotary kiln. The research work laid a solid foundation for improving rotary kiln retorting device and accumulated lots of useful experimental data and experience.