Prediction of solid discharge rates of pulverized coal from an aerated hopper

A pilot-scale loop feeding system was used to investigate the discharge behavior of pulverized coal. Experiments on discharge of pulverized coal from an aerated hopper under several aeration rates were carried out. The flow properties of the pulverized coal were measured with different shear testing methods. A previously developed predictive model was adopted to estimate the discharge of pulverized coal. Powder flow properties extrapolated to zero consolidation were used for model application. A correlation between the voidage between aggregates and the gas superficial velocity was obtained from independent fluidization tests and applied into aerated discharge with proper modifications. Acceptable agreement was found between the predicted and the measured solid discharge rates. These results indicate the applicability of the model also to predict the powder flow from pilot scale units.