The pulse tube flash dryer is an improved version of the straight tube flash dryer. By changing the cross-sectional area of drying pipe, the starch granules and airflow will produce turbulence phenomenon, and vortex phenomenon will be produced at the corner. As the diameter of the pipe is thickened, the wind speed will decrease and the drying time will be prolonged.
When the diameter of starch granules suddenly changes, a negative pressure phenomenon will be produced in starch granules, which makes the water quickly released. Therefore, the airflow drying of starch with multiple expansion joints (pulse section) is to use pure hot air as working medium to transfer heat energy to starch particles, so that the water attached to the surface of starch particles and part of the water contained in the starch granules will be turned into steam and mixed into the airflow in the drying pipe. Finally, cyclone separator is used to separate starch from hot air and water vapor, thus reducing the moisture in starch. This is the flash drying process of starch.
The advantages of air flow drying：
1. They are specially designed for starch drying. They have different design features for potato starch, kudzu flour, lotus root starch and wheat starch.
2. High air volume, low temperature drying. Starch is dried at low temperature to avoid starch gelatinization and ensure its quality.
3. The reasonable air network system has low pressure and low power consumption.
4. Anti-blocking and closed air device + large Angle unloader to ensure smooth feeding without blockage.
5. Automatic control, through reasonable arrangement of multi-point temperature detector, moisture detector, control the feeding speed
6. The vertical space of the equipment is developed, occupying a small space on the ground.