DEM SIMULATION OF CHAR COMBUSTION IN A FLUIDIZED BED

A numerical study was conducted based on the discrete element method (DEM) to analyse the thermodynamic characteristics and NOx emission of burning chars in a fluidized bed. The fluctuations of char particle temperature were investigated taking into account the effects of particle-particle heat conduction, particle-gas heat convection, radiation and combustion. Calculated results show that the maximum temperature of char particles is about C ° ± 5 50 higher than the average bed temperature, which is determined by the oxygen concentration nearby and the heat transfer properties of their surrounding gas and particles. NO emission is found to be greatly affected by the temperature of burning char particles.