Experimental and numerical simulation of drying of lignite in a microwave assisted fluidized bed

The characteristics of lignite drying in a microwave fluidized bed were simulated using Fluent software based on Euler-Euler flow model. The simulation results fitted the experimental data reasonably well. The results showed that the fluidization quality and drying rate of lignite increased with an increase of microwave power and air temperature. Along with the drying process, the predicted value of lignite moisture content was slightly smaller than the experimental value. The hydrodynamics and heat transfer coefficients of lignite microwave drying in a fluidized bed were investigated on the basis of simulation results. The difference of solid volume fraction is identified although a good agreement is obtained the experiment. The heat transfer coefficients increased with the increasing of microwave power, air temperature and air velocity, while decreased with the increasing of drying time.