7MJ/Nm3。Energy balance analysis and calculations were made for two common kinds of biomass. It was proved that the heat of fixed carbon combustion was sufficient for volatile pyrolysis. The pressure distribution for cold cases in the dual fluidized bed was obtained by cold experiments. Finally, during the experiments of pellet gasification in dual fluidized bed, combustion conditions were able to be smoothly switched to gasification conditions with stable operation, and the calorific value of gas was able to reach 7MJ/Nm3.