What are the causes of cyclone separator blockage?
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What are the causes of clogging in the cyclone separator of CFB boilers? The image shows the observation hole in the lower cone of the cyclone separator, from which red ash is emitted from time to time!
I’ve had congestion here because the dust cleaning wasn’t done in time
Does a cyclone separator also need to have its dust cleaned? Logically, there shouldn’t be any dust accumulation
Which part of the cyclone separator is blocked?
1) Increase in furnace pressure； (2) Bed pressure drops [delayed return of material] ； (3) Increased negative pressure in the tail flue [no smoke flow] ； (4) Increased flue gas resistance [no power] (5) High level alarm for the return material valve ； (6) The temperature of the return valve rises rapidly. (7) Increase in primary air volume ； (8) The steam temperature, steam pressure, and load all decrease.
Below the central cylinder of the cyclone separator, above the vertical pipe – in other words, at the area where the circular part meets the conical part – there is coking and blockage. Ugh! Poking with a stick every day,
1. Generally, blockages tend to occur at the bell mouth area (the area where the diameter decreases); residue accumulation there reduces the flow area. Every time the furnace is shut down, it is necessary to check whether the insulation layer in this area is damaged, worn away, uneven, or covered with residue. 2. The furnace differential pressure is too high, the amount of circulating ash is excessive, and the return material is insufficient. 3. Problems with the return material valve itself (problems with the air cap, issues with the Roots blower, coking on the lower bed surface, or coking at the return material inlet inside the furnace, etc.)
Why does the negative pressure in the tail flue increase [with no smoke flowing in]?
The return valve is not suitable; the interior of the separator is not unobstructed, and its inner wall is uneven； The furnace height is low, the secondary air supply is inadequate, and small particles do not burn completely