Comparative study on the molecular evolution of changqing petroleum coke during air and pure oxygen combustion: A ReaxFF method analysis

Based on reactive force field (ReaxFF) simulation, the molecular evolution mechanism of air combustion simulation and pure oxygen combustion simulation of Changqing petroleum coke was studied. On the basis of the original petroleum coke molecular model, N2 and O2 molecules were added to construct the air combustion simulation model and the pure oxygen combustion simulation model respectively. The number of molecules, main products, and typical hydrocarbon gases in the two simulation results were analyzed by setting up the LAMMPS in. file. Finally, the molecular changes of pyrrole and pyridine were described. The results show that the main reaction interval of pure oxygen combustion is earlier than that of air combustion. In the main reaction temperature range, the reaction rate of pure oxygen combustion is higher than that of simulated air combustion. At 170 ps, the two simulations reaction speed is the fastest time point; Pyridine is more stable than pyrrole. The research on the distinction and comparison of two kinds of simulation has certain guiding significance for the clean utilization of petroleum coke combustion process in industry.