What is the function of a separator in the CFB boiler?

Circulating fluidized bed boiler (CFB) is a fluidized combustion boiler. Its main structure includes combustion chamber and circulating furnace. It has many advantages such as high thermal efficiency and low pollution, and is especially suitable for inferior coal. During use, all parts of the boiler are playing their respective roles. Here, we will focus on the function of the separator of circulating fluidized bed boiler.

The working principle of circulating fluidized bed boiler separator

Separator is one of the three core components of circulating fluidized bed boiler. Its working principle is that the dusty flue gas coming out of the furnace outlet is introduced along the tangential direction from the side of the cylinder, and the flue gas flow rate increases. The airflow is introduced along the center line at the top of the cylinder, and the flue gas flow rate increases. The airflow rotates downward along the central cylinder at the top of the cylinder, and turns upward before reaching the end of the cone, and the clean flue gas is discharged from the cyclone separator through the central cylinder.

Function of separator in the CFB boiler

1. The separator of circulating fluidized bed boiler is mainly used to separate the dust particles in the flue gas by the centrifugal force produced by the rotating dusty flue gas.
2. The efficiency of the separator determines the circulation ratio. When the circulation ratio is low, the change of separator efficiency has little effect on the circulation ratio. When the separator efficiency is high, a little change in the separator efficiency will cause a great change in the circulation ratio.
3. In the high-rate circulating fluidized bed boiler, the change of separator efficiency has a greater impact on the fly ash concentration. Therefore, it is easy to control the steam temperature by using low rate circulation. The superheater is aimed at the existence of condensed water, and the way of temperature adjustment is nothing more than setting a desuperheater between the secondary superheaters, using a surface-reduction type desuperheater, using feedwater spray, or using self-made condensed water.