Evaporation is the main way to achieve drying by heating. The drying way now used is to provide the kinetic energy of evaporation for products through heat conduction, convection and thermal radiation. Now there is another drying technology, which is microwave drying technology. Micro drying technology instantly transforms the electromagnetic energy into the kinetic energy of material molecules, that is to say, the microwave energy absorbed by the material itself generates heat and makes the water evaporated. Because microwave heating has a certain penetration, so microwave heating is actually a three-dimensional heating, that is, the product is heated inside and outside, so the microwave drying technology has the following characteristics: skills, fast drying, low drying temperature, timely heating, no thermal inertia.