Can. Make the hot air and solid particles to be dried in direct contact, and make the solid particles to be dried (starch) suspended in the fluid, and thus the two-phase contact area is large, strengthening the process of heat and mass transfer, the airflow should be used in the drying unit operation of bulk materials. Starch (amylum) is a polymer carbohydrate, is a polysaccharide polymerized from glucose molecules.