Circulating fluidized bed boiler consists of boiler body and auxiliary equipment;

1. Boiler body: mainly includes starting burner, air chamber, air distribution device, furnace, gas-solid separator, material return device, steam drum, downcomer, water wall, superheater, economizer, air preheater, etc.

2. Auxiliary equipment: mainly including blower, induced draft fan, return air fan, crusher, coal feeder, slag cooler, dust collector, desulfurization and denitrification equipment, chimney, etc.

Second, the structural characteristics of circulating fluidized bed boiler:

The main structural feature of fluidized bed boiler is material circulation system, which consists of air distribution device, combustion chamber, gas-solid separator, material return device, ignition device and other equipment.

Combustion chamber, separator and return device are called the three core components of circulating fluidized bed boiler, which constitute the particle circulation loop of circulating fluidized bed boiler, which is an obvious feature of circulating fluidized bed boiler that is different from other boilers in structure and is a unique system of circulating fluidized bed boiler.

Third, the working principle of circulating fluidized bed boiler

After the fuel is crushed into a suitable particle size by a crusher, it is fed from the upper part of the air distribution plate of the combustion chamber by a coal feeder, mixed with the hot boiling materials in the combustion chamber, and quickly heated. The fuel is quickly ignited and burned, and a large number of solid particles are taken out of the combustion chamber under the action of high airflow speed. After the separated materials are separated by the gas-solid separator, they return to the combustion chamber through the material return device to continue to participate in combustion. The high-temperature flue gas from the separator exchanges heat with the convection heating surface in the tail flue, and is discharged from the chimney after passing through the dust collector.

The coal, wind and smoke system mentioned above is called the combustion system of boiler, which is generally called "furnace".

On the other hand, the boiler feed water is pumped into the economizer for preheating, then enters the drum, then enters the downcomer and water wall for heating and evaporation, and then returns to the drum. The steam after steam-water separation enters the superheater for heating, and then is sent to the user through the main steam pipeline.