(Basic knowledge) What is the bed pressure difference of a circulating fluidized bed boiler?

The bed pressure difference in a circulating fluidized bed boiler is a parameter that reflects the thickness of the material layer in the combustion chamber. Typically, the pressure difference measured between the upper surface of the wind chamber and the combustion chamber is used as the value for monitoring the layer pressure difference; during operation, the thickness of the material layer is determined by monitoring this layer pressure difference value. The greater the layer thickness, the higher the measured differential pressure value. During boiler operation, the thickness of the bed material directly affects the quality of fluidization in the boiler. If the bed thickness is too large, it may lead to poor fluidization, resulting in coking in the furnace or even flameout. The thickness of the material layer (i.e., the differential pressure across the material layer) can be adjusted by discharging the bottom material through the slag discharge pipe at the bottom of the furnace. During use, the user should set upper and lower limits for the bed pressure difference based on the type of coal being burned, to use as reference points for starting and stopping the discharge of the bottom material.

The pressure difference between the wind pressure in the downwind chamber and the pressure head in the combustion chamber.