The Simulation Study Of FG-DVC Model Application On Pyrolysis Of Oil Shale

With the rapid development of the world economy, national demand for energy is growing and conventional oil resources can not meet the rapid growth in oil demand. Oil shale, as an ideal natural supplement and alternative energy sources, has become the focus of national energy development. However, in the process of development and utilization of oil shale are related to the characteristics of oil shale pyrolysis problem. Studying pyrolysis characteristics and oil shale reaction mechanism are the foundation of oil shale carbonization, gasification and combustion processes. Judging from the research status, most researchers study on the characteristics of apparent pyrolysis and few study on the intrinsic characteristics of oil shale pyrolysis. In this thesis, FG-DVC model is used to analyze the relationship between structure and reactivity of oil shale pyrolysis, which combines with NMR and TG-FTIR technology.In order to study the relationship between chemical structure and pyrolysis products of oil shale, NMR chemical structure of the four samples are analyzed to obtain the number of the carbon skeleton and functional group information, then a series of experiments for oil shale and kerogen were performed at various heating rates: 10℃/min, 20℃/min, and 50℃/min using TG-FTIR(Thermogravimetric Analysis-Fourier Transform Infrared Spectroscopy)for characterization. Quantitative analysis was performed for pyrolysis products including CH4, CO,CO2, H2 O and shale oil. The results demonstrate that the temperature at which evolution rate of pyrolysis products reaches a peak value and increases as the heating rate increases, and minerals in oil shale promotes the decomposition and release of the organic matter in the sample during the pyrolysis. The kinetic parameters were obtained for the previously stated pyrolysis products,of which include activation energy(E)and pre-exponent factor(A), and possess values distributed between 183-267kJ·mol-1 and 3.0×109-2.8×1013s-1, respectively. FG-DVC(Functional Group-Depolymerization Vaporization Crosslinking)pyrolysis model based on chemical structure of fuel was employed to simulate the evolution process of CH4, CO, CO2, H2 O, and shale oil under three different heating rates. Simulation results are in strong agreement with experimental data via TG-FTIR, indicating the feasibility of modelling the pyrolysis process of oil shale and kerogen using pyrolysis theory based on FG-DVC model. And The prediction value of the yield of the pyrolysis products for kerogen using FG-DVC model was more accurate than oil shale,Which illustrated that the presence of minerals in oil shale is one of the important reasons for the error of prediction of FG-DVC model.