The document outlines the startup sequence for a CFBC burner. It involves 14 steps: 1) satisfying pre-interlocks, 2) satisfying main interlocks, 3) satisfying purge interlocks, 4) starting purge for 5 minutes, 5) purge completing, 6) resetting MFTs, 7) satisfying gas firing permissives, 8) burners becoming ready for start, 9) starting burner A through 10 automatic commands, and 10) burner A gas firing starting. It provides details on the conditions that must be met at each step.

1. CFBC BURNER STARTUP
SEQUENCE
ASHVANI SHUKLA
RELIANCE INDUSTRIES LTD.

2. BURNER MANAGEMENT
SYSTEM
• FOLLOWING STEPS TO BE CARRIED OUT FOR BURNER START-UP
• Step-1: Pre-interlock satisfied
• Step-2:Main interlock satisfied
• Step-3: Purge interlock satisfied
• Step-4: Purge required will come after all permissive satisfied and
purge Start command will be given by operator
• Step-5: Purge in progress will run for 5 minutes(after purge start
command will be given by operator this indication will appear for 5
minutes) .
• Step-6 :Purge completed. After purge completed one timer will
start for 15 minutes, in between this time operator has to start
burner or else purge required will come and again operator will go
for purging

3. • Step-7: MFT reset will be done by manual pushbutton. Manual open
command will be given for pilot gas MFT and NG gas MFT. After open
command given to both MTF(Pilot gas and NG gas) individual header vent
will be closed automatically.
• Step-8: Gas firing permissive satisfied
• Step-9: Burner A—F ready for start
• Step-10: After start command given following step will be carried out in
auto mode:
• Gas gun inserted command
• Ignition on command, Pilot gas up stream and down stream valve open
command, pilot gas vent valve close command.
• Pilot flame on(It will be detected by a flame scanner and remain on for 5
second to permit the opening of NG gas valve).
• Gas block valve up stream and down stream valve open cmd., gas block
valve vent valve close c0mmand
• Burner on.
•

4. • PRE INTERLOCK CONDITIONS:
• Black furnace trip
• Total airflow not very low
• I.D.Fan running
• S.A. Fan running
• P.A. Fan running
• Furnace pressure not very high
• Furnace pressure not very low
• Emergency stop P.B. not operated
• Drum level not very low
• Drum level not very high
• Instrument air pressure not very low

5. MAIN-INTERLOCK CONDITIONS:
• Pre-interlock satisfied
• Fluidized bed pressure above 120MMWC
• Purge finished OR any one burner in on condition OR bed
temperature greater than the minimum ignition temperature of
coal

6. PURGE-INTERLOCK CONDITIONS:
1.All fuel flow is stopped
2.Flow path open (Primary and secondary air path along with flue gas path should be open for
free flow of air during purging.
Pre-interlock condition satisfied
Pilot gas MFT in close position OR
Pilot gas header vent valve in open position
OR
NG MFT valve in close position OR
NG header vent valve in open position
No flame in furnace
All gas block valves in close position
OR Purge finished

7. PURGE START COMMAND:
Purge interlock is satisfied
Purge is not finished AND All gas block valves in close position AND No flame in furnace
Start command from local OR remote
PURGE IN PROGRESS
Purge start command is given
Purge timer is running for 5 minutes.
All air sleeve dampers in open position
Boiler air flow rate is above purge rate.
PURGE COMPLETED:
Purge timer completed
No Burner Running

8. FURNACE FIRING PERMISSIVE SATISFIED:
• Main interlock is satisfied
• SA air flow is not very low
• PA air flow is not very low
• Minimum bed fluidized pressure > 127MMWC
PERMISSIVE FOR PILOT GAS MFT OPEN COMMAND
• Furnace firing permissive is satisfied
• All pilot gas block valves are in close position OR Any one burner is running
• Pilot gas MFT stop push button not operated
• Pilot gas MFT stop push button is not operated
• Open command from remote/local

9. PERMISSIVE FOR PILOT GAS HEADER VENT CLOSE COMMAND
• 1. Pilot gas MFT open command is given
• 2. Any one burner is running OR Any one pilot gas burner is started OR Pilot gas pressure
is not high
• 3. Pilot gas header vent close command not given OR Pilot gas header vent closed
feedback
NG GAS MFT OPEN COMMAND
• Furnace firing permissive satisfied
• All gas block valves are in close position OR Any one burner is running
• Gas MFT stop push button not operated
• Open command from remote OR local
•

10. NG GAS HEADER VENT CLOSE COMMAND
• Gas MFT open command given
• Any one burner is running OR Any one pilot gas burner is started OR Gas pressure is not high
• Gas header vent close command is not given OR Gas header vent is in close position
•
GAS FIRING PERMISSIVE:
Gas PCV in start position
Gas FCV in closed position
•NG pressure is not very low OR Any one burner is running
•NG pressure is not very high
•Furnace firing permissive is satisfied
•MFT Reset bit is available
•NG MFT valve open feedback
OR Any one burner is running

11. BURNER READY TO START FOR BURNER-A:
•Gas firing permissive satisfied
•Burner A is running OR Burner-A gas block valves are in close position
•Stop push button not operated from remote AND local
•Burner-A ignition sparking time not over OR Burner-A flame is on
•Burner-A not tripped
No ignitor running
Burner –A flame not on
MFT not tripped
•OR Burner-A gas firing started

12. BURNER-A START COMMAND GIVEN:
•Burner ready for start
•Start command given from local or remote
BURNER-A GAS GUN INSERT COMMAND
Burner –A start command given
BURNER-A PILOT GAS UPSTREAM/DOWN STREAM OPEN AND VENT VALVE
CLOSE COMMAND
•Burner –A gas firing permissive is satisfied AND Burner-A is not running
•Burner-A pilot block valve closed feedback OR Burner-A pilot flame on
•Burner-A gas gun is inserted
•Furnace firing permissive is satisfied
•Pilot gas pressure is not high
•Pilot gas pressure isnot low OR Any one pilot burner is on
•Pilot MFT valve open feedback

13. BURNER-A IGNITOR ON COMMAND
•Burner –A gas gun is inserted
•Burner-A gas firing is started
BURNER-A GAS UPSTREAM/DOWN STREAM OPEN AND VENT
VALVE CLOSE COMMAND
•Burner –A air sleeve damper open feedback
•Burner-A ignition sparking time is over
•Burner-A pilot flame is on OR Burner-A flame is on
•Burner-A gas gun inserted
•Natural gas MFT valve open feedback
Burner-A gas firing is started.