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BOILER AND AUXILIARIES Presentation Transcript
1.POWER PLANT OPERATION BOILER & AUXILIARIES
2. Presentation outline
OPERATING PROCEDURE
APH
ID, FD AND PA FAN
FURNACE PURGE
BOILER LIGHT UP
MILLING SYSTEM
OPERATING PROCEDURE
APH
ID, FD AND PA FAN
FURNACE PURGE
BOILER LIGHT UP
MILLING SYSTEM
3.Before starting any equipment…..
ENSURE
No PTW is pending on the equipment which is to be normalized .
Equipment is properly boxed up and no maintenance staff working.
Local operator is informed before the equipment is started.
ENSURE
No PTW is pending on the equipment which is to be normalized .
Equipment is properly boxed up and no maintenance staff working.
Local operator is informed before the equipment is started.
4.Pre start checks before light up
5.Equipment cooling water is charged in boiler side and proper venting is done.
Service water /filter water for sealing in the boiler bottom is charged .Get the clearance from AHP for sealing of bottom hopper.
Service and instrument air is charged and air for SADC and burner tilt are charged .
Fire water/ sprinkler water is available in boiler area.
Service water /filter water for sealing in the boiler bottom is charged .Get the clearance from AHP for sealing of bottom hopper.
Service and instrument air is charged and air for SADC and burner tilt are charged .
Fire water/ sprinkler water is available in boiler area.
6.DM water is available .
Ensure the availability of aux. steam .
Ensure 6.6 kv, 415 volt , 220 volt DC,110 V AC, 24 V DC SUPPLIES are normal . Ensure that all MCC s are charged. Both buses are charged independently and Bus coupler is in OFF position .ensure all chargers are in charged condition and all the batteries are in healthy condition .
All unit protections/interlocks ( boiler ,turbine & generator ) are checked and recorded in the protection register .
Ensure the availability of aux. steam .
Ensure 6.6 kv, 415 volt , 220 volt DC,110 V AC, 24 V DC SUPPLIES are normal . Ensure that all MCC s are charged. Both buses are charged independently and Bus coupler is in OFF position .ensure all chargers are in charged condition and all the batteries are in healthy condition .
All unit protections/interlocks ( boiler ,turbine & generator ) are checked and recorded in the protection register .
7.Start LDO PUMP or charge LDO line upto firing floor if other units are running.
Start HFO pump or charge charge HFO line upto firing floor on long recirculation if other unit is running. also inform other units .
charge atomising air and atomising steam lines.
Keep boiler drum vents,SH vents , SH drains ,CRH drains, HRH drains open.
Ensure all low point drains are closed .
Start HFO pump or charge charge HFO line upto firing floor on long recirculation if other unit is running. also inform other units .
charge atomising air and atomising steam lines.
Keep boiler drum vents,SH vents , SH drains ,CRH drains, HRH drains open.
Ensure all low point drains are closed .
8.Inform shift chemist to take water sample before water filling in the boiler and take clearance from shift chemist. Inform him to prepare hydrazine , ammonia and phosphate solution for dosing . Check availability of all LP and HP dozing pumps .
Fill water in the boiler upto normal level by running one BFP .
Ensure at least two ESP passes are clear and their inlet / outlet gates are open. Elect. Supply of fields are kept off .
Inspect the boiler up to drum floor . Ensure that all manholes /peepholes are closed.
Fill water in the boiler upto normal level by running one BFP .
Ensure at least two ESP passes are clear and their inlet / outlet gates are open. Elect. Supply of fields are kept off .
Inspect the boiler up to drum floor . Ensure that all manholes /peepholes are closed.
9.Ensure start up vent and ECO recirculation valve are open.
Charge the SCAPH LINE .
Keep the burner tilt at 0 deg ( horizontal )
Ensure boiler and auxiliaries areas are clean , safe and properly illuminated .
Charge the SCAPH LINE .
Keep the burner tilt at 0 deg ( horizontal )
Ensure boiler and auxiliaries areas are clean , safe and properly illuminated .
10. AIR PRE-HEATER OPERATION
PRE START CHECKS
Support bearing/ guide bearing lub oil pumps RUNNING and lub oil coolers are CHARGED.
Bearing temperature NOT HIGH (less than 60oC)
Electrical supply to APH motor is AVAILABLE.
Local operation - Isolating valves of air motors are 'OPEN' and bypass valves of air motor solenoids are 'CLOSED'.
'Air motors' lub oil level ADEQUATE
Service air pressure is ADEQUATE (> 5 Kg/cm2)
PRE START CHECKS
Support bearing/ guide bearing lub oil pumps RUNNING and lub oil coolers are CHARGED.
Bearing temperature NOT HIGH (less than 60oC)
Electrical supply to APH motor is AVAILABLE.
Local operation - Isolating valves of air motors are 'OPEN' and bypass valves of air motor solenoids are 'CLOSED'.
'Air motors' lub oil level ADEQUATE
Service air pressure is ADEQUATE (> 5 Kg/cm2)
11.APH STARTING PROCEDURE
WHEN BOTH APHS ARE OFF
START air motor of APH.
Air motors ON indications come on
Isolating dampers of APHs start opening.
INSTRUCT local operator to check, locally for any abnormal sounds from bearings/seals.
START air heater electrical motor.
Breaker CLOSED & its indication comes on UCB
Associated air motor stops.
Starting current shoots up and comes down to normal load current.
WHEN BOTH APHS ARE OFF
START air motor of APH.
Air motors ON indications come on
Isolating dampers of APHs start opening.
INSTRUCT local operator to check, locally for any abnormal sounds from bearings/seals.
START air heater electrical motor.
Breaker CLOSED & its indication comes on UCB
Associated air motor stops.
Starting current shoots up and comes down to normal load current.
12. Isolating dampers of the air heater remain open.
Isolating dampers of the other air heater, not in service, start closing if its air motor is not ON.
INSTRUCT local operator to check, locally for any abnormal sounds from bearings/seals.
There should be no abnormal hunting in air heater amperes meter readings.
There should be no abnormal sounds from air pre-heater seals or bearings.
Bearing temperatures must be within the normal range (65 0C -75 0C)
Isolating dampers of the other air heater, not in service, start closing if its air motor is not ON.
INSTRUCT local operator to check, locally for any abnormal sounds from bearings/seals.
There should be no abnormal hunting in air heater amperes meter readings.
There should be no abnormal sounds from air pre-heater seals or bearings.
Bearing temperatures must be within the normal range (65 0C -75 0C)
13. SHUT DOWN PROCEDURE
CHECK Corresponding ID & FD Fans are running.
UNLOAD associated ID/FD fans, gradually.
The other pair of ID/FD fans (if running) starts loading up on auto.
STOP the associated FD fan. Maintain desired oxygen percentage.
Furnace total airflow indication drops slightly. Reduce firing if required.
STOP the associated ID fan.
Furnace pressure increases slightly. Maintain furnace draft between -5 to - 10 mm wcl.
STOP air heater electrical motor.
With a few seconds time delay, the isolating dampers of the air heater are closed, if the other AIR HEATER is in service.
CHECK Corresponding ID & FD Fans are running.
UNLOAD associated ID/FD fans, gradually.
The other pair of ID/FD fans (if running) starts loading up on auto.
STOP the associated FD fan. Maintain desired oxygen percentage.
Furnace total airflow indication drops slightly. Reduce firing if required.
STOP the associated ID fan.
Furnace pressure increases slightly. Maintain furnace draft between -5 to - 10 mm wcl.
STOP air heater electrical motor.
With a few seconds time delay, the isolating dampers of the air heater are closed, if the other AIR HEATER is in service.
14.ID FAN OPERATION
PRE START CHECKS
WHEN BOTH THE FANS ARE OFF
Fan lub oil pressure is ADEQUATE (1.2 Kg/cm2).
Fan bearing temperature is NOT HIGH (< 60 0C .)
All permissive for the fan AVAILABLE. ''Inlet guide vanes min.'' & Inlet/outlet dampers closed''
Local operator is informed before the fan is started.
PRE START CHECKS
WHEN BOTH THE FANS ARE OFF
Fan lub oil pressure is ADEQUATE (1.2 Kg/cm2).
Fan bearing temperature is NOT HIGH (< 60 0C .)
All permissive for the fan AVAILABLE. ''Inlet guide vanes min.'' & Inlet/outlet dampers closed''
Local operator is informed before the fan is started.
15.Inlet/outlet dampers start closing. Inlet vanes come to minimum.
The fan breaker is CLOSED after inlet/outlet dampers close fully.
Inlet/outlet dampers open up after a time delay.
Inlet/outlet dampers of the other fan closes and regulating vanes comes to minimum position.
ADJUST inlet guide vanes to maintain furnace draught between - 5 mm. to -10 mm.
INSTRUCT the local operator to check for abnormal bearing vibration and temperature.
The fan breaker is CLOSED after inlet/outlet dampers close fully.
Inlet/outlet dampers open up after a time delay.
Inlet/outlet dampers of the other fan closes and regulating vanes comes to minimum position.
ADJUST inlet guide vanes to maintain furnace draught between - 5 mm. to -10 mm.
INSTRUCT the local operator to check for abnormal bearing vibration and temperature.
16.WHEN ONE FAN IS RUNNING
All pre-start checks are OVER.
START fan motor
Fan motor current settles down at no load current.
Inlet/outlet dampers start opening.
Maintain furnace draft -5 to - 10 mm wcl.
Maintain desired airflow.
ADJUST bias to 50% and furnace draught set point to 45%.
Check furnace draught is maintained between 5 mm wcl to-10 mm wcl.
TRANSFER vane controllers of both fans to ''AUTO''.
Inlet vanes modulate to maintain set value of furnace draught.
All pre-start checks are OVER.
START fan motor
Fan motor current settles down at no load current.
Inlet/outlet dampers start opening.
Maintain furnace draft -5 to - 10 mm wcl.
Maintain desired airflow.
ADJUST bias to 50% and furnace draught set point to 45%.
Check furnace draught is maintained between 5 mm wcl to-10 mm wcl.
TRANSFER vane controllers of both fans to ''AUTO''.
Inlet vanes modulate to maintain set value of furnace draught.
17.SHUT DOWN PROCEDURE
Reduce the coal firing and air flow so as to sustain with one ID fan.
SELECT IGV controls of fan to manual.
IGVs control transfers to manual.
REGULATE IGVs of the ID Fan to minimum.
ID fan discharge pressure decreases.
ID fan current come to minimum, other fan loading increases.
STOP the ID fan.
Total airflow drops slightly avoid Boiler trip.
The inlet and outlet dampers close on interlock.
REGULATE the inlet guide vanes of the running ID fan to desired loading.
Maintain furnace draught at -5 mm wcl.
Note : If associated FD fan is in service it will be necessary to unload FD fan and stop it before stopping ID fan;
18.CHECK before starting the FD fan, all start permissive is satisfied.
Fan control oil temp is NORMAL (<55 oC)
Fan blade pitch is MINIMUM and Discharge damper is CLOSED
Fan control / lub oil pressure is ADEQUATE.
Fan bearing temperature is NOT HIGH (<60 0C.)
CHECK if FD fan is lined up locally for starting.
Fan lub oil system is LINED UP and oil coolers are charged.
Lub oil tank level is ADEQUATE.
Anyone LOP is ON and other one is on AUTO.
Fan EPBs are in RELEASED position.
FD fan blade pitch controller is OPERATIONAL and is REMOTE.
Instrument air pressure is AVAILABLE.
Any or both ID fans: APHs' secondary air isolating dampers are OPEN.
SCAPH is available
FD fan discharge dampers are OPERATIONAL and electrical supplies are AVAILABLE.
19.STARTING PROCEDURE.
WHEN BOTH THE FANS ARE OFF
All pre-start checks are OVER.
START the FD fan motor.
Discharge dampers start closing
Blade pitch comes to minimum.
As soon as discharge damper closes, "Blade pitch minimum“ permissive comes on.
Fan takes starting current and comes down to no load current after a while.
Discharge damper starts opening (for the fan started).
FD fan discharge pressure increases.
Blade pitch for the other fan goes to minimum.
Reduce the coal firing and air flow so as to sustain with one ID fan.
SELECT IGV controls of fan to manual.
IGVs control transfers to manual.
REGULATE IGVs of the ID Fan to minimum.
ID fan discharge pressure decreases.
ID fan current come to minimum, other fan loading increases.
STOP the ID fan.
Total airflow drops slightly avoid Boiler trip.
The inlet and outlet dampers close on interlock.
REGULATE the inlet guide vanes of the running ID fan to desired loading.
Maintain furnace draught at -5 mm wcl.
Note : If associated FD fan is in service it will be necessary to unload FD fan and stop it before stopping ID fan;
18.CHECK before starting the FD fan, all start permissive is satisfied.
Fan control oil temp is NORMAL (<55 oC)
Fan blade pitch is MINIMUM and Discharge damper is CLOSED
Fan control / lub oil pressure is ADEQUATE.
Fan bearing temperature is NOT HIGH (<60 0C.)
CHECK if FD fan is lined up locally for starting.
Fan lub oil system is LINED UP and oil coolers are charged.
Lub oil tank level is ADEQUATE.
Anyone LOP is ON and other one is on AUTO.
Fan EPBs are in RELEASED position.
FD fan blade pitch controller is OPERATIONAL and is REMOTE.
Instrument air pressure is AVAILABLE.
Any or both ID fans: APHs' secondary air isolating dampers are OPEN.
SCAPH is available
FD fan discharge dampers are OPERATIONAL and electrical supplies are AVAILABLE.
19.STARTING PROCEDURE.
WHEN BOTH THE FANS ARE OFF
All pre-start checks are OVER.
START the FD fan motor.
Discharge dampers start closing
Blade pitch comes to minimum.
As soon as discharge damper closes, "Blade pitch minimum“ permissive comes on.
Fan takes starting current and comes down to no load current after a while.
Discharge damper starts opening (for the fan started).
FD fan discharge pressure increases.
Blade pitch for the other fan goes to minimum.
20.Discharge damper for the other fan closes.
Instruct local operator to check bearing vibration and temperature.
ADJUST the blade pitch controller to get desired airflow.
Fan discharge pressure increases.
Maintain furnace draught between-5 to 10 mm wcl and airflow 30%-40% during purging.
Fan amperage changes accordingly.
Oxygen percentage varies accordingly.
Wind box pressure also varies, with FD fan loading.
MAINTAIN the Wind box to furnace DP as per boiler loading.
Wind box to furnace DP should be maintained as shown:
Boiler load<30% 30 to 40 mm of wcl
Boiler load>30% 100 mm of wcl
21. WHEN ONE FAN IS RUNNING
All pre-start checks are OVER.
Both ID fans are in SERVICE.
START the FD fan
Discharge damper of the fan starts opening
Furnace pressure and total airflow increases slightly.
ADJUST the blade pitch to maintain desired airflow and wind box pressure.
Fan discharge pressure increases
Fan amperage increases accordingly
Furnace pressure increases slightly
CHECK vibration and bearing temperatures.
TRANSFER FD fans blade pitch control to AUTO.
FD fan blades modulate maintain set oxygen percentage.
Oxygen in flue gas varies accordingly
22. FURNACE PURGE PROCEDURE
Start APHs and at least one ID and one FD fan. Maintain furnace draft between -5 to -10 mm of WCL and maintain air flow between 30 % to 40 % of boiler full load air flow.
CHECK ALL THE PURGE PERMISSIVE IS satisfied on the FSSS console.
"No boiler trip" command is AVAILABLE.
Drum lvl not high ( > 125 mm)
Drum lvl not low ( < - 125 mm)
All ignitor valves are CLOSED.
All HFO nozzle valves are CLOSED.
HFO and ignitor trip valves are CLOSED.
All pulverisers and associated raw coal feeders are OFF.
All mill hot air gates are CLOSED
Both PA fans are OFF.
Instruct local operator to check bearing vibration and temperature.
ADJUST the blade pitch controller to get desired airflow.
Fan discharge pressure increases.
Maintain furnace draught between-5 to 10 mm wcl and airflow 30%-40% during purging.
Fan amperage changes accordingly.
Oxygen percentage varies accordingly.
Wind box pressure also varies, with FD fan loading.
MAINTAIN the Wind box to furnace DP as per boiler loading.
Wind box to furnace DP should be maintained as shown:
Boiler load<30% 30 to 40 mm of wcl
Boiler load>30% 100 mm of wcl
21. WHEN ONE FAN IS RUNNING
All pre-start checks are OVER.
Both ID fans are in SERVICE.
START the FD fan
Discharge damper of the fan starts opening
Furnace pressure and total airflow increases slightly.
ADJUST the blade pitch to maintain desired airflow and wind box pressure.
Fan discharge pressure increases
Fan amperage increases accordingly
Furnace pressure increases slightly
CHECK vibration and bearing temperatures.
TRANSFER FD fans blade pitch control to AUTO.
FD fan blades modulate maintain set oxygen percentage.
Oxygen in flue gas varies accordingly
22. FURNACE PURGE PROCEDURE
Start APHs and at least one ID and one FD fan. Maintain furnace draft between -5 to -10 mm of WCL and maintain air flow between 30 % to 40 % of boiler full load air flow.
CHECK ALL THE PURGE PERMISSIVE IS satisfied on the FSSS console.
"No boiler trip" command is AVAILABLE.
Drum lvl not high ( > 125 mm)
Drum lvl not low ( < - 125 mm)
All ignitor valves are CLOSED.
All HFO nozzle valves are CLOSED.
HFO and ignitor trip valves are CLOSED.
All pulverisers and associated raw coal feeders are OFF.
All mill hot air gates are CLOSED
Both PA fans are OFF.
23.All fire ball and oil discriminating flame scanners must be sensing NO FLAME.
AC/DC electrical power supplies to FSSS panels are AVAILABLE.
All auxiliary air dampers of the wind box are MODULATING& furnace to wind box DP > 40 mm wcl.
Oil elevation dampers also modulate with aux. air dampers when no oil gun is in service
Boiler airflow less than 30% annunciation goes off.
Boiler airflow and wind box pressure are maintained at less than 40% and 40 mm wcl, respectively.
All burners at all elevations and in all corners, come to horizontal position "Burner tilts horizontal and Airflow less than 40%“ permissive comes ON.
If all other permissive are satisfied, "Purge Ready” indication comes ON.
24. FURNACE PURGE PROCEDURE
PRESS "push to purge" button on the FSSS console
"Purging" indication comes on the FSSS console.
If in the meanwhile none of the permissive are lost, "Purge complete" indication comes on FSSS console, with a time delay of 5 minutes.
MFR-A & MFR-B get reset. Boiler Trip "cause" also resets.
"Boiler MFR Trip" annunciation clears off.
AC/DC electrical power supplies to FSSS panels are AVAILABLE.
All auxiliary air dampers of the wind box are MODULATING& furnace to wind box DP > 40 mm wcl.
Oil elevation dampers also modulate with aux. air dampers when no oil gun is in service
Boiler airflow less than 30% annunciation goes off.
Boiler airflow and wind box pressure are maintained at less than 40% and 40 mm wcl, respectively.
All burners at all elevations and in all corners, come to horizontal position "Burner tilts horizontal and Airflow less than 40%“ permissive comes ON.
If all other permissive are satisfied, "Purge Ready” indication comes ON.
24. FURNACE PURGE PROCEDURE
PRESS "push to purge" button on the FSSS console
"Purging" indication comes on the FSSS console.
If in the meanwhile none of the permissive are lost, "Purge complete" indication comes on FSSS console, with a time delay of 5 minutes.
MFR-A & MFR-B get reset. Boiler Trip "cause" also resets.
"Boiler MFR Trip" annunciation clears off.
25.BOILER LIGHT-UP
CHECK these conditions before the boiler light up
Boiler "MFR TRIP" is RESET.
Pre-start checks for boiler light up have been COMPLETED.
Fuel oil system is adequately LINED-UP.
Super heater / Reheater air vents are OPEN.
SH/RH start-up vents are OPEN.
Ignition air fans are LINEDUP for operation.
Open heavy fuel oil recirculation valve
OPEN heavy fuel oil trip valve
Short re-circulation valve closes.
OPEN heavy fuel oil control valve.
HFO header pressure rises up to 10 Kg/cm2 (approx.)
26."HFO" inlet and re-circulation flow start increasing
"HFO header pressure very low" alarms clear off.
HFO temperature in the HFO header increases up to 110 oC.
OPEN Ignitor oil trip valve
Ignitor oil trip valve opens up.
Ignitor air fans A & B, start automatically.
Ignitor oil and ignitor air pressure increase up to 23 Kg/cm2 and 400 mm wcl, respectively.
"Ignitor air to furnace DP low“ & "Ignitor oil/Atomising air pressure low" & "Ignitor oil/HFO trip valve closed" alarms clear off.
CHECK these parameters are within their operation limits.
Drum level normal (-60 mm. to 0, preferably on lower side).
27.HFO temp. 110 oC . (Min. temp. required is 95 oC).
HFO atomising steam pressure 8.75 Kg/cm2
Light oil pressure more than 15 Kg/cm2.
Ignitor atomising air pressure 5 to 7 Kg/cm2
Wind box pressure between 35 to 40 mm wcl
ADJUST HFO header pressure set point to 50%(13 Kg/cm2) and TRANSFER its control to auto.
HFO pressure controller transfers to auto and modulates to maintain the set HFO header pressure.
CLOSE heavy fuel oil re-circulation valve.
HFO re-circulation flow valve closes.
HFO re-circulation flow comes to minimum position
28.HFO header pressure goes up and is brought down to set HFO pressure by auto controller.
PUSH " Pair 1-3 or 2-4 Start" push button.
In the first 10 secs of the pair start trial time; ignitors 1-3 and 2-4 are proven, in the associated oil elevation.
"Ignitor Stop" light goes off in the associated elevation.
If minimum 3 ignitors are proven on, command goes to corner 1 or 2, for the gun to advance to the firing position, provided associated ignitor is on
Command is given to open the associated atomising steam valve after the gun is fully advanced.
After the atomising steam valve is fully open, command is given to open the corresponding HFO corner nozzle valve.
29.25 second later command goes to corner 3 or 4, as the case may be, HFO nozzle valve open.
Associated discriminating oil flame scanners start sensing flame.
HFO control valve modulates to maintain set HFO header pressure.
ADJUST heavy oil pressure controller to desired firing
HFO header pressure changes accordingly
Oil scanner performance improves with increasing header pressure.
PUSH second pair.
"Start"(Pair 1-3/2-4) push button.
HFO guns advance and corresponding nozzle valves open up.
30.PUSH "Ignitor Stop" push button to remove ignitors if the oil flame is stable in every corner in the elevation
All the elevation ignitors go off.
If any discriminating scanner flickers to show 'no flame', corresponding oil nozzle valve is closed automatically.
CHECK these conditions before the boiler light up
Boiler "MFR TRIP" is RESET.
Pre-start checks for boiler light up have been COMPLETED.
Fuel oil system is adequately LINED-UP.
Super heater / Reheater air vents are OPEN.
SH/RH start-up vents are OPEN.
Ignition air fans are LINEDUP for operation.
Open heavy fuel oil recirculation valve
OPEN heavy fuel oil trip valve
Short re-circulation valve closes.
OPEN heavy fuel oil control valve.
HFO header pressure rises up to 10 Kg/cm2 (approx.)
26."HFO" inlet and re-circulation flow start increasing
"HFO header pressure very low" alarms clear off.
HFO temperature in the HFO header increases up to 110 oC.
OPEN Ignitor oil trip valve
Ignitor oil trip valve opens up.
Ignitor air fans A & B, start automatically.
Ignitor oil and ignitor air pressure increase up to 23 Kg/cm2 and 400 mm wcl, respectively.
"Ignitor air to furnace DP low“ & "Ignitor oil/Atomising air pressure low" & "Ignitor oil/HFO trip valve closed" alarms clear off.
CHECK these parameters are within their operation limits.
Drum level normal (-60 mm. to 0, preferably on lower side).
27.HFO temp. 110 oC . (Min. temp. required is 95 oC).
HFO atomising steam pressure 8.75 Kg/cm2
Light oil pressure more than 15 Kg/cm2.
Ignitor atomising air pressure 5 to 7 Kg/cm2
Wind box pressure between 35 to 40 mm wcl
ADJUST HFO header pressure set point to 50%(13 Kg/cm2) and TRANSFER its control to auto.
HFO pressure controller transfers to auto and modulates to maintain the set HFO header pressure.
CLOSE heavy fuel oil re-circulation valve.
HFO re-circulation flow valve closes.
HFO re-circulation flow comes to minimum position
28.HFO header pressure goes up and is brought down to set HFO pressure by auto controller.
PUSH " Pair 1-3 or 2-4 Start" push button.
In the first 10 secs of the pair start trial time; ignitors 1-3 and 2-4 are proven, in the associated oil elevation.
"Ignitor Stop" light goes off in the associated elevation.
If minimum 3 ignitors are proven on, command goes to corner 1 or 2, for the gun to advance to the firing position, provided associated ignitor is on
Command is given to open the associated atomising steam valve after the gun is fully advanced.
After the atomising steam valve is fully open, command is given to open the corresponding HFO corner nozzle valve.
29.25 second later command goes to corner 3 or 4, as the case may be, HFO nozzle valve open.
Associated discriminating oil flame scanners start sensing flame.
HFO control valve modulates to maintain set HFO header pressure.
ADJUST heavy oil pressure controller to desired firing
HFO header pressure changes accordingly
Oil scanner performance improves with increasing header pressure.
PUSH second pair.
"Start"(Pair 1-3/2-4) push button.
HFO guns advance and corresponding nozzle valves open up.
30.PUSH "Ignitor Stop" push button to remove ignitors if the oil flame is stable in every corner in the elevation
All the elevation ignitors go off.
If any discriminating scanner flickers to show 'no flame', corresponding oil nozzle valve is closed automatically.
31.CHECK that all PA fans start permissive is satisfied.
PA fan bearing temp NOT HIGH (<60oC.).
PA lub oil pressure is ADEQUATE.
PA fan inlet guide vanes are at MINIMUM position.
PA fan FSSS start command is AVAILABLE (BOILER MFR: RESET & all mill cold air dampers are less than 5% OPEN).
PA fan discharge damper is CLOSED.
CHECK that PA fan is locally line up for starting.
PA fan lub oil coolers are CHARGED from waterside.
PA Fan LOP : ON and other pump is on AUTO
PA fan lub oil tank level is ADEQUATE.
PA fans EPBS are in RELEASED position.
PA fan guide vanes are on REMOTE. Instrument air pre. is AVAILABLE.
PA fan discharge damper is OPERATIONAL and power supply is AVAILABLE.
PA fan bearing temp NOT HIGH (<60oC.).
PA lub oil pressure is ADEQUATE.
PA fan inlet guide vanes are at MINIMUM position.
PA fan FSSS start command is AVAILABLE (BOILER MFR: RESET & all mill cold air dampers are less than 5% OPEN).
PA fan discharge damper is CLOSED.
CHECK that PA fan is locally line up for starting.
PA fan lub oil coolers are CHARGED from waterside.
PA Fan LOP : ON and other pump is on AUTO
PA fan lub oil tank level is ADEQUATE.
PA fans EPBS are in RELEASED position.
PA fan guide vanes are on REMOTE. Instrument air pre. is AVAILABLE.
PA fan discharge damper is OPERATIONAL and power supply is AVAILABLE.
32. CHECK. if air system is lined up before starting PA fan.
APHs primary air isolation dampers are OPEN.
Seal air fans are LINEDUP and their suction dampers are OPEN.
Mills' cold air dampers on REMOTE. Instrument air pre. is AVAILABLE.
Furnace purging is COMPLETED and MFRs are in RESET condition.
All man material is removed from the pulverisers.
33. WHEN BOTH THE FANS ARE OFF
CHECK these conditions before starting the PA fan.
All pre-start checks COMPLETED.
Fan discharge dampers 100% OPEN.
Regulating vanes are 100% OPEN.
Lub. oil pressure is ADEQUATE. (>1.8 Kg)
FSSS start command (MFR - A&B reset on the FSSS console and all mills cold air dampers are less than 5% open) is ON.
Bearing temperature NOT HIGH. (<60 0C).
START the PA fan motor.
Discharge damper starts closing.
Regulating vanes of the fan get closed.
APHs primary air isolation dampers are OPEN.
Seal air fans are LINEDUP and their suction dampers are OPEN.
Mills' cold air dampers on REMOTE. Instrument air pre. is AVAILABLE.
Furnace purging is COMPLETED and MFRs are in RESET condition.
All man material is removed from the pulverisers.
33. WHEN BOTH THE FANS ARE OFF
CHECK these conditions before starting the PA fan.
All pre-start checks COMPLETED.
Fan discharge dampers 100% OPEN.
Regulating vanes are 100% OPEN.
Lub. oil pressure is ADEQUATE. (>1.8 Kg)
FSSS start command (MFR - A&B reset on the FSSS console and all mills cold air dampers are less than 5% open) is ON.
Bearing temperature NOT HIGH. (<60 0C).
START the PA fan motor.
Discharge damper starts closing.
Regulating vanes of the fan get closed.
34.All mills cold air dampers go to less than 5% open and "FSSS start command" permissive comes on.
Fan current shoots up to 700A and comes to No load current 70A.
Discharge damper opens and for the other fan, it closes and regulating vanes of the other fan also goes to minimum position.
ADJUST the PA fan guide vanes to get desired hot PA header pressure of 760 mm wcl
PA fan discharge pressure goes up.
PA fan current go up.
PA header pressure goes up to 760 mm wcl, gradually.
INSTRUCT the local operator to check bearing Temperature & vibration locally. There must be no abnormal sound from the fan or bearings.
Fan current shoots up to 700A and comes to No load current 70A.
Discharge damper opens and for the other fan, it closes and regulating vanes of the other fan also goes to minimum position.
ADJUST the PA fan guide vanes to get desired hot PA header pressure of 760 mm wcl
PA fan discharge pressure goes up.
PA fan current go up.
PA header pressure goes up to 760 mm wcl, gradually.
INSTRUCT the local operator to check bearing Temperature & vibration locally. There must be no abnormal sound from the fan or bearings.
35.WHEN ONE FAN IS RUNNING
All pre-start checks are COMPLETED.
LOP: ON. Lub. Oil pressure ADEQUATE (1.8 -2.5 KSC)
Discharge damper CLOSED.
Regulating vanes are in MINIMUM position.
Bearing temperature NOT HIGH (< 600C).
FSSS start command is AVAILABLE.
Local operator informed prior to starting of the fan.
START the PA fan motor.
Fan current goes up to 700A and comes down to no load current of 70A.
Discharge damper open up.
INSTRUCT the local operator to check bearing vibration and temperature locally.
36.WHEN ONE FAN IS RUNNING
ADJUST the fan guide vanes to get desired PA header pressure and equalise fan loadings.
Fan discharge pressure read approx. 800 mm wcl.
PA header pressure rises to 760 mm wcl.
ADJUST the fan biasing and header pre. set point to 50% & 80% respectively and transfer vane controllers to auto.
Header pressure and biasing set points have been provided over the IGV controllers of PA fan A&B respectively.
IGVs of both fans modulate to maintain set header pressure.
37.WITH BOTH THE FANS RUNNING
TRANSFER the IGV controls to manual
STOP all the pulverisers in excess of three from the top.
Three pulverisers only can be in service with one PA fan.
Cut-in oil support if odd combination of mills are running.
REDUCE IGVs of the fan to their minimum position.
Fan discharge pressure comes down.
Notice the other fan loading going up, to maintain the set header pressure.
STOP the fan motor. The fan breaker opens
Discharge damper starts closing.
Regulating vanes go to minimum, position.
All pre-start checks are COMPLETED.
LOP: ON. Lub. Oil pressure ADEQUATE (1.8 -2.5 KSC)
Discharge damper CLOSED.
Regulating vanes are in MINIMUM position.
Bearing temperature NOT HIGH (< 600C).
FSSS start command is AVAILABLE.
Local operator informed prior to starting of the fan.
START the PA fan motor.
Fan current goes up to 700A and comes down to no load current of 70A.
Discharge damper open up.
INSTRUCT the local operator to check bearing vibration and temperature locally.
36.WHEN ONE FAN IS RUNNING
ADJUST the fan guide vanes to get desired PA header pressure and equalise fan loadings.
Fan discharge pressure read approx. 800 mm wcl.
PA header pressure rises to 760 mm wcl.
ADJUST the fan biasing and header pre. set point to 50% & 80% respectively and transfer vane controllers to auto.
Header pressure and biasing set points have been provided over the IGV controllers of PA fan A&B respectively.
IGVs of both fans modulate to maintain set header pressure.
37.WITH BOTH THE FANS RUNNING
TRANSFER the IGV controls to manual
STOP all the pulverisers in excess of three from the top.
Three pulverisers only can be in service with one PA fan.
Cut-in oil support if odd combination of mills are running.
REDUCE IGVs of the fan to their minimum position.
Fan discharge pressure comes down.
Notice the other fan loading going up, to maintain the set header pressure.
STOP the fan motor. The fan breaker opens
Discharge damper starts closing.
Regulating vanes go to minimum, position.
38.WITH ONE FAN IS RUNNING
SHUTDOWN all running pulverizes one by one. Take Oil guns in service.
Boiler total fuel flow starts decreasing.
Oxygen percentage the flue gases starts increasing.
Associated mills cold air dampers start closing.
Total airflow keeps on decreasing.
ID fan vanes modulate (on auto), to maintain set furnace draught.
REDUCE the IGV of the PA fan to its minimum position.
PA fan discharge pressure starts decreasing.
PA header pressure decreases to 400 mm wcl, approximately.
39.WITH ONE FAN IS RUNNING
STOP the PA fan & Rack-out the breaker if required for maintenance.
Breaker open indication comes on.
Guide vanes of both PA fans will remain at minimum position.
Discharge dampers of both PA fans go to 100% open.
40. Milling System
PRE START CHECKS (Typical: Raymond Bowl Mill) Local
Ensure R.C. Bunker level satisfactory.
R.C. feeder and mill properly boxed up and no maintenance staff working.
Gear box oil level normal. Lub. oil coolers charged.
Pulveriser START PERMIT is AVAILABLE. (Boiler total airflow is < 40% and all burners are HORIZONTAL). Alternatively, if anyone coal feeder is proven then start permit will come from the proven feeder.
Tramp iron gate open.
Cold air gate 100 % open. Hot air gate closed.
Mill outlet valve open.
Seal air valve 100 % open.
"No unsuccessful start" permissive for pulveriser is ON.
Mill fire fighting system ready.
SHUTDOWN all running pulverizes one by one. Take Oil guns in service.
Boiler total fuel flow starts decreasing.
Oxygen percentage the flue gases starts increasing.
Associated mills cold air dampers start closing.
Total airflow keeps on decreasing.
ID fan vanes modulate (on auto), to maintain set furnace draught.
REDUCE the IGV of the PA fan to its minimum position.
PA fan discharge pressure starts decreasing.
PA header pressure decreases to 400 mm wcl, approximately.
39.WITH ONE FAN IS RUNNING
STOP the PA fan & Rack-out the breaker if required for maintenance.
Breaker open indication comes on.
Guide vanes of both PA fans will remain at minimum position.
Discharge dampers of both PA fans go to 100% open.
40. Milling System
PRE START CHECKS (Typical: Raymond Bowl Mill) Local
Ensure R.C. Bunker level satisfactory.
R.C. feeder and mill properly boxed up and no maintenance staff working.
Gear box oil level normal. Lub. oil coolers charged.
Pulveriser START PERMIT is AVAILABLE. (Boiler total airflow is < 40% and all burners are HORIZONTAL). Alternatively, if anyone coal feeder is proven then start permit will come from the proven feeder.
Tramp iron gate open.
Cold air gate 100 % open. Hot air gate closed.
Mill outlet valve open.
Seal air valve 100 % open.
"No unsuccessful start" permissive for pulveriser is ON.
Mill fire fighting system ready.
41. PRE START CHECKS (Typical: Raymond Bowl Mill) UCB
Ensure no PTW pending.
Ensure at least one P.A. fan and a seal air fan is in service. Check the header pressure for both primary and seal air is normal.
Check that mill ignition energy is O.K. (Minimum 3 out of 4 gun nozzle valves in adjacent elevation are open and elevation oil flow is more than 30% OR adjacent feeder speed is more than 50% and boiler load is more than 30%.
Check that mill start permissive as per FSSS are satisfied
Ensure E.P. zones have been charged (for first mill).
Get the electrical supply for the mill.
Inform the local operator to be near mill for start up.
Start the mill
Ensure no PTW pending.
Ensure at least one P.A. fan and a seal air fan is in service. Check the header pressure for both primary and seal air is normal.
Check that mill ignition energy is O.K. (Minimum 3 out of 4 gun nozzle valves in adjacent elevation are open and elevation oil flow is more than 30% OR adjacent feeder speed is more than 50% and boiler load is more than 30%.
Check that mill start permissive as per FSSS are satisfied
Ensure E.P. zones have been charged (for first mill).
Get the electrical supply for the mill.
Inform the local operator to be near mill for start up.
Start the mill
42. POST START CHECKS
Local -Check there is no abnormal sound from mill. Check return oil flow from upper bearing is satisfactory. Check all the rollers are rotating and the rate of reject is normal (after the mill is loaded).
U.C.B.-Check mill starting time and current. Ensure that they are normal. Open hot air gate. Warm up the mill.
Start the RC feeder and load the mill gradually.
Keep the air flow through mill - 54 T/hr.
Keep watch on mill differential to avoid mill choking.
Maintain mill outlet temperature between 75°C to 80°C.
As the pressure, temperature of main steam shoots up with coal firing proper check should be kept on these parameters. (Especially for first mill).
Local -Check there is no abnormal sound from mill. Check return oil flow from upper bearing is satisfactory. Check all the rollers are rotating and the rate of reject is normal (after the mill is loaded).
U.C.B.-Check mill starting time and current. Ensure that they are normal. Open hot air gate. Warm up the mill.
Start the RC feeder and load the mill gradually.
Keep the air flow through mill - 54 T/hr.
Keep watch on mill differential to avoid mill choking.
Maintain mill outlet temperature between 75°C to 80°C.
As the pressure, temperature of main steam shoots up with coal firing proper check should be kept on these parameters. (Especially for first mill).
43. MILL SHUTDOWN PROCEDURE
TRANSFER mill feeder and fuel master controller to manual.
Fuel master and feeder control transfer to manual.
REDUCE feeder speed to minimum, gradually.
Coal flow to mill starts coming down.
Other running feeders start loading up, to maintain boiler loading, if on auto.
STOP the mill feeder.
Hot air gate closes with a time delay of 30 sec approx.
Mill current and differential pressure start reducing as the mill becomes empty, gradually.
EVACUATE the mill reject chamber locally and STOP the mill.
Mill temperature comes down to less than 50oC.
Mill CAD goes to <5% open
Airflow to furnace drops slightly.
44. MILL SHUTDOWN PROCEDURE
TRANSFER mill feeder and fuel master controller to manual.
Fuel master and feeder control transfer to manual.
REDUCE feeder speed to minimum, gradually.
Coal flow to mill starts coming down.
Other running feeders start loading up, to maintain boiler loading, if on auto.
STOP the mill feeder.
Hot air gate closes with a time delay of 30 sec approx.
Mill current and differential pressure start reducing as the mill becomes empty, gradually.
EVACUATE the mill reject chamber locally and STOP the mill.
Mill temperature comes down to less than 500C.
Mill CAD goes to <5% open
Airflow to furnace drops slightly.
45. Electrostatic precipitators are not normally taken into service (i.e. the zones are not changed) when firing on oil only and, if possible, the EP should be bypassed whilst firing on oil only. This is done to prevent oil deposition on electrodes which can reduce E.P. efficiency drastically.
If EP bypasses are not fitted, the gas flow should be limited to one of the main passes during the initial oil firing stage of the pressure raising.
Anti-condensation heaters & hopper heaters, if provided must be taken into service well before boiler light up is initiated.
The EP zones must be taken into service just before coal firing is started in the boiler. The frequency of rapping should be properly adjusted and their operation must be locally checked.
TRANSFER mill feeder and fuel master controller to manual.
Fuel master and feeder control transfer to manual.
REDUCE feeder speed to minimum, gradually.
Coal flow to mill starts coming down.
Other running feeders start loading up, to maintain boiler loading, if on auto.
STOP the mill feeder.
Hot air gate closes with a time delay of 30 sec approx.
Mill current and differential pressure start reducing as the mill becomes empty, gradually.
EVACUATE the mill reject chamber locally and STOP the mill.
Mill temperature comes down to less than 50oC.
Mill CAD goes to <5% open
Airflow to furnace drops slightly.
44. MILL SHUTDOWN PROCEDURE
TRANSFER mill feeder and fuel master controller to manual.
Fuel master and feeder control transfer to manual.
REDUCE feeder speed to minimum, gradually.
Coal flow to mill starts coming down.
Other running feeders start loading up, to maintain boiler loading, if on auto.
STOP the mill feeder.
Hot air gate closes with a time delay of 30 sec approx.
Mill current and differential pressure start reducing as the mill becomes empty, gradually.
EVACUATE the mill reject chamber locally and STOP the mill.
Mill temperature comes down to less than 500C.
Mill CAD goes to <5% open
Airflow to furnace drops slightly.
45. Electrostatic precipitators are not normally taken into service (i.e. the zones are not changed) when firing on oil only and, if possible, the EP should be bypassed whilst firing on oil only. This is done to prevent oil deposition on electrodes which can reduce E.P. efficiency drastically.
If EP bypasses are not fitted, the gas flow should be limited to one of the main passes during the initial oil firing stage of the pressure raising.
Anti-condensation heaters & hopper heaters, if provided must be taken into service well before boiler light up is initiated.
The EP zones must be taken into service just before coal firing is started in the boiler. The frequency of rapping should be properly adjusted and their operation must be locally checked.
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