Hopper discharge is one of the most important components in the entrained-flow gasification technology of pulverized coal. Safe and stabilized hopper discharge is of great economic significance. The effect of feeding gas

including air and CO2 on hopper discharge was studied in the loop feeding system of pulverized coal. Both gravity discharge and aerated discharge were examined and analyzed. The behavior and flowability of powders would be influenced by their previous bulk or fluidized state. For gravity discharge

the pulverized coal fed by CO2 showed a higher void and thus corresponded to higher discharge rate. For aerated discharge

the pulverized coal fed by air was hard to be fluidized by CO2

resulting in lower discharge rate.