Abstract: Based on the fluidized bed divided into three areas, the exchanges of gas and solid between the both areas of fluidized bed were studied through a cold model. Experiments showed that it is feasible to reform three areas in fluidized bed to both areas, which is helpful to operating and decreasing the investment of fluidized bed. If fluidization index is properly raised, the heat exchange between combustion and gasification areas will meet the needs of operating, and the heat value of gas will also increase. A vertical device in fluidized bed will help to increase the heat value of gas.