Drying is a process of heat and mass transfer. Energy is an important part of the definition of drying. Driven by energy, material drying and heat source are very important to the whole drying process and are important components of drying equipment. The heat source is used for drying equipment, and the fuel also includes gas, liquid and solid.

According to the working principle and equipment structure of drying equipment, it is very important to choose the appropriate fuel. If the flue gas from solid fuel (coal) combustion is used, there are many gases in the gas, which can only be used as an indirect heat source to heat the air, and then the hot air is used as a drying medium for drying. This process is suitable for flue gas-air heat exchange equipment, including fin heat exchanger, and the method of heat source is also common in drying equipment.

In recent years, with the development of science and technology, the types of heat sources of dryers are also increasing. With the continuous improvement of new technology, heat pipe heat exchanger came into being. In addition, the use of heating and drying media by non-electric radiator is also improving.

In the choice of heat source, the following principles are the reduction of energy consumption. There are many problems in the heat source of drying equipment used by many enterprises. The main problem is that the heat can't match the drying equipment in the production process. The generated heat is low, the product moisture is high, the generated heat is high, the energy used by the whole drying equipment is too high, and the product cost is increased. Manufacturers of drying equipment need to choose suitable heat sources for dryers.