Causes and solutions for failure of biomass thermal oil boiler

Causes and solutions for the tripping of the exhaust fan of the biomass thermal oil furnace:

(1) Phenomenon

① Issue an accident signal and sound and light alarm;

② Interlock the tripping of the coal mill and coal feeder;

③ The negative pressure of the coal mill inlet decreases or even reverses, and the outlet temperature of the coal mill increases;

④ Boiler load, steam pressure and steam temperature drop, and combustion in the furnace fluctuates.

(2) Causes of failure of the biomass thermal oil furnace

① Power failure, accident button action or protection action;

② All induced draft fans or forced draft fans trip and the exhaust fan trips.

(3) Treatment

① Adjust the negative pressure in the furnace and reset the tripping switch;

② Trip the pulverizing system backflow, that is, close the hot air door of the coal mill inlet, the exhaust fan inlet air door, and open the cold air door.

③ Restart after finding out the cause and handling it. When restarting, the pulverizing system must be ventilated and the powder must be extracted.

④ If operation cannot be resumed within a short period of time, close the main air damper at the coal mill inlet and the air damper at the pulverizer discharger outlet, and open the tertiary cooling air supply. During the shutdown period, closely monitor the temperature of all locations in the pulverizing system and, if necessary, apply inert gas protection. If spontaneous combustion occurs, initiate firefighting.

⑤ When restarting the pulverizing system after an accidental trip, proceed slowly while ventilating and warming the mill to completely remove any accumulated pulverized gas in the system.

⑥ For exhaust gas pulverized gas combustion systems, tripping the pulverizer discharger should automatically trigger the corresponding pulverizer feeder. If this does not occur, manually stop the pulverizer feeder to reduce boiler load and stabilize combustion. Ventilate and purge the air ducts during the initial air cycle after recovery to prevent blockage.