Precautions for Circulating Fluidized Bed Boilers

The following items should be paid attention to during the working process of circulating fluidized bed boiler:

1. During the cooking period, the medium and low water level must be ensured. When the furnace is cooking, the liquid medicine must not enter the super heater, so as to prevent the suspended solids from depositing in the serpentine tube and causing blockage. After the boiler is finished, the boiler should be shut down for waterproofing, the attachments and residues on the inner wall of the super heater should be thoroughly cleaned, and the super heater should be rinsed with soft water for about 2 hours before trial operation.

2. The super heater exhaust valve and trap must be opened before ignition. When the pressure rises, close the exhaust valve and open the sub-cylinder intake valve and trap at the same time. When the drum pressure reaches the specified value, close the trap until about 10% of the flow rate, then close the trap.

3. During operation, if the furnace temperature is high, the desuperheating water flow should be opened. At this time, the trap should be closed, and the desuperheating water flow should be turned off and the trap should be opened at the same time.

4. During the operation of the boiler, if the desuperheating water has increased to the maximum, the steam temperature of the super heater is still very high, and the steam temperature can be reduced by the following methods:

(1) Increase the circulating ash volume of the boiler and reduce the particle size of the coal feed.

(2) Appropriately reduce the amount of coal fed and lower the furnace temperature.

(3) Under the condition of oxygen permit, the secondary air can be appropriately reduced.

5. If the desuperheating water is turned off and the steam temperature of the super heater is still low, the steam temperature can be increased by the following methods:

(1) Let off some circulating ash and increase the temperature of the flue gas at the outlet of the furnace.

(2) The secondary air volume can be appropriately increased.

6. Before operating the boiler, carefully check the internals of the drum, and require tight welds and no leaks.

7. Strictly control the burning of high-sulfur coal to prevent high-temperature corrosion of the super heater.

8. Regularly check the abrasion resistance of the high temperature super heater. The worn-out protective tile should be repaired even if it is welded, the worn-out protective tile should be replaced immediately, and the steering protective tile should be corrected immediately.

9. During the operation of the boiler, the blowdown operation shall be strengthened, continuous blowdown shall not be interrupted, and regular blowdown shall not be less than once per shift.

Want to know more details about circulating fluidized bed (CFB) boilers? Welcome to consult online customer service, or directly call +86 177 1999 3430, ZBG Boiler Group will serve you wholeheartedly!