Circulating fluidized bed boiler, return air for fluidization
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What is the main function of the fluidization air in the return conveyor of a circulating fluidized bed boiler? What happens when the pressure is increased or decreased? What effects does it have on the load and on combustion?
Enhancing the fluidization of the circulating ash ensures smooth return of the ash. Depending on the amount of ash present, an appropriate pressure and air volume can be selected (manufacturers of boilers generally provide reference values). With smooth ash return, heat can be transferred more effectively to the furnace, which is beneficial for combustion
This post was last edited by han*chen on 2017-7-24 at 13:53. U-shaped return valve: There are two types, loose-air type and return-air type. The former is used to loosen the circulating ash at the lower part of the vertical pipe (the descending section), causing it to move diagonally as a whole toward the ascending section； The latter is to move the circulating ash from the rising section into the furnace. The ratio of loosening air to return air is generally 1:3, although this ratio needs to be determined through commissioning tests. Its function is to recycle the separated circulating ash for combustion, thereby improving combustion efficiency.
Is the return feeder for LoopSeal the same? Figure 1 shows the diagram drawn in the factory; Figure 2 shows the central cylinder inside the cyclone separator!
What would happen if the frequency of the fluidization fan were increased in order to raise the pressure in the fluidization chamber of the return feeder?
Oh my god, is your central tube in such a state?
The center jet is under maintenance. What would happen if the pressure in the return material fluidization chamber were increased? In recent months, the lower cone of the cyclone separator has frequently experienced coking, and when there is positive pressure in the furnace, fly ash sprays out from the observation port
Can this central cylinder returner work properly? What are the symptoms? Share it with me!
If the pressure of the fluidizing air in the return conveyor is too low, below the bed pressure at the same height, won’t the circulating ash fail to return to the furnace? If the pressure of the fluidizing air in the return stream is too high, could it cause air to flow back up through the discharge pipe of the separator? That will lead to a decrease in separation efficiency.
Yeah! The fluidization fans in the plant are Roots fans, with a fluidization air pressure of around 16 kPa! What if I increase the frequency conversion? Will the wind pressure increase? Has the amount of return material increased, or has it increased in speed? Recently, the cyclone separator, specifically the cone area, has been constantly clogged with ash