Air preheater is generally referred to as an air preheater. Mostly used for coal-fired power plant boilers. It can be divided into two types: tube box type and rotary type, among which rotary type is further divided into wind cover rotary type and heating surface rotary type. Power plant boilers commonly use heating surface rotary preheaters. The application in boilers is generally divided into two compartments, three compartments, and four compartments, among which the four compartments are more commonly used in circulating fluidized bed boilers.
The working principle of the tube box preheater: relatively simple, the flue gas flows through the outside of the tube box, and the air passes through the inside of the tube box, and heat is transferred through different temperature differences. The principle is the same as that of economizer, superheater, etc.
The working principle of a rotary preheater is that the preheater rotor component is composed of tens of thousands of heat transfer elements. When the air preheater rotates slowly, the flue gas and air flow alternately in reverse through the air preheater. The thermal storage element absorbs heat on the flue gas side and releases heat on the air side, thereby achieving the preheating effect of reducing the exhaust gas temperature of the boiler and increasing the hot air temperature.