Analysis of Combustion Behavior and Comparison of Kinetic Models of Oil Shale

This study examines the thermal characteristics and kinetics of oil shale combustion using thermogravimetric analysis (TGA) at various heating rates. The combustion process includes three stages: dehydration, main combustion (70-80% mass loss), and mineral decomposition. Kinetic analysis using model-free (Ozawa-Flynn-Wall, Kissinger) and model-based (multi-step reaction kinetics) methods revealed that the second-order reaction model (F2) had the highest accuracy. Oil shale combustion involves multi-step reactions, with activation energy and pre-exponential factors varying nonlinearly with conversion rates. Combining model-free and model-based methods provides insights for optimizing combustion processes and equipment design for the efficient utilization of unconventional energy resources.