ansferring surface has self-cleaning function. Compressing and swell-stirring functions make the material mixed uniformly. The material perform the movement of piston flow along the shaft. The difference of the temperature, humidity and mixing effect are very small in the different axial area. The blade dryer is capable to perform combustion under low temperature if we adopt thermal oil as heating media, such as Ca2S04 2H2O is combusted into Ca2SO4 1/2H2O, NaHCO3 is combusted into Na2CO3 and s