supercritical boiler operation and unit startup and shutdown operation of plant

1. SUPERCRITICAL UNIT STARTUP
AND SHUTDOWN

2. INTRODUCTION
 INDIA’S FIRST 66O MW SUPER CRITICAL UNIT SYNCHRONISED BY ADANI
POWER LTD, MUNDRA IN OCT 2010 IN RECORD TIME OF 36 MONTHS.
 COMMISSIONED 4Nos. 660MW UNITS IN A YEAR.
 ADANI IS THE FIRST COMPANY IN INDIA TO EARN CARBON CREDIT.

4. START-UP SEQUENCE
 BOP SYSTEM READYNESS
 BOILER FLUSHING: COLD/HOT
 BOILER LINE UP AND LIGHT UP.
 TURBINE LINE UP.
 TURBINE ROLLING.
 SYNCHRONISATION
 PHASE CHANGE OVER
 FULL LOAD

5. START UP MODES
 COLD START UP:HP & IP SHAFT METAL
TEMP <204°C
 WARM START UP: HP & IP METAL TEMP
IN BETWEEN 204 TO 400°C
 HOT START UP :HP & IP METAL TEMP
>400°C

6. HP
T
IPT LPT A LPT B
CPP
GSC
Condensor
(HP) Condensor
(LP)
HPH-1HPH-2HPH-3
EXT From
CRH
LPH -5 LPH -6
LPH -7A
LPH -7B
LPH -8A
LPH -8B
3
Deaerator
Boiler
CEP
3x50%
FCS
5 56 6
Economiser
1482 TPH
1994 TPH
(MD BFBP
1x35%)
7
8
7
8 8
77
8
11+1 8 2x7 2x7
RH
1
TDBFP 2X50%

7. PRE STARTUP READYNESS
 HT/LT POWER SUPPLY READINESS
 WATER SYSTEM: FIRE WATER,SERVICE WATER,DMP,CW & ACW.
 CCCW SYSTEM
 COMPRESSOR SYSTEM
 AUXILIARY STEAM. (S/B UNIT OR AUX BOILER).
 START CEP AND MDBFP.
 CHECK THE BCP SYSTEM IS READY.

8. WHY BCP ?
 TO ASSIST CIRCULATION IN BOILER WATER WALL
 TO INCREASE THE CIRCULATION VELOCITY
 TO AVOID DNB (Departure from Nucleate Boiling) IN LOW LOAD.
 TO REDUCE THE OVER HEATING AND UNDUE STRESSES ON WATER
WALL TUBES.
 TO AVOID DRY OUT OF WATER WALL TUBES WHEN LOAD IS REDUCED.

9. BCP FILLING ,PURGING & FLUSHING
 PURPOSE-
- TO FILL THE MOTOR CAVITY.
 RECOMMENDED MOTOR FILLING WATER QUALITY
- CONDUCTIVITY <1 µs/cm
- BOILER FEED WATER
- TEMP.<= 45 O
C
- CL-
<= 50 PPM
- pH >= 6.5
- SUSPENDED SOLIDS <= 5 PPM
 FILLING,PURGING & FLUSHING WATER REQUIREMENT
- MOTOR INITIAL FILLING FLOW RATE : MAX. 5 L/MIN

10. PRE BOILER FLUSHING
 START CEP.
 FILL & DRAIN FROM DEAERATOR UNTIL
REQUIRED WATER QUALITY IS ACHIEVED.
( Fe<500 Ppb.)
 START MDBFP.
 START THE BOILER COLD/HOT FLUSHING TO
REDUCE THE Fe & SiO2 CONTENT IN FEED
WATER.

11. Sampling Fe+
Above
500ppb
Below
500ppbMIXER
Boiler flushing
HOTWELL
CW
LINE
BCP
START-UP
LINE
ECO
WW
SP SP

12. BOILER COLD FLUSHING
COLD FLUSHING
 WATER WALL TEMP REQUIRED 105-120 DEG.C (TEMP
MAINTAINED BY DEAERATOR PEGGING STEAM)
 COLD OPEN FLUSHING QUALIFIES Fe < 500PPB
SiO2 < 100PPB
 THEN CPU WILL BE TAKEN IN SERVICE TO REDUCE WATER LOSS AND
IMPROVE QUALITY.
 COLD CYCLIC FLUSHING QUALIFIES Fe < 100PPB
SIO2 < 50PPB
(ALL ANALYSIS FROM SEPARATOR DRAIN)

13. BOILER HOT FLUSHING
HOT FLUSHING
 WATER WALL TEMP REQUIRED 150-190 DEG.C (TAKE OIL GUNS
OF BC ELEVATION)
 HOT OPEN FLUSHING START UP CRITERIA FE > 100PPB
SIO2 > 50PPB
 IF HOT CYCLIC FLUSHING CRITERIA IF FE < 100PPB
SIO2 < 50PPB
 HOT CYCLIC FLUSHING QUALIFIES IF FE < 50PPB
SIO2 < 30PPB
 AFTER COLD FLUSHING START BCP WITH MINIMUM 30% FEED FLOW &
THROTTLE FRS VALVE.

14. BOILER LINE UP AND LIGHT UP
 FUEL OIL SYSTEM: LDO/HFO PUMPS
 ESP HEATERS & RAPPERS
 AIR FLUE GAS SYSTEM: APH,IDF, FDF & SCANNER FAN.
 MAINTAIN AIR FLOW : 30% - 40%.
 FURNACE PURGE: 300 Sec.
 LIGHT UP BOILER WITH OIL GUNS AT BC (LDO)
ELEVETION.
 CONTINUE HOT FLUSHING UNTIL REQD.WATER QUALITY
IS ACHIEVED
 THEN TAKE CD ELEVETION GUNS. IF REQUIRED TAKE 2
NO. GUNS IN AB ELEVETION.

15. BOILER LINE UP AND LIGHT UP
 CONTINUOUS APH SOOT BLOWING TO BE DONE AT THE TIME OF
OIL FIRING.
 PR RISING RATE- 0.05 MPA/MIN. BETWEEN 0-1 MPA
 PR RISING RATE 0.1 MPA/MIN. BETWEEN 1 – 2 MPA
 PR RISING RATE 0.2 MPA/MIN. ABOVE 2 MPA
 FURNACE EXIT GAS TEMP MUST BE BELOW 538°C FOR REHEATER
PROTECTION (UNTIL HP-LPBP IS CHARGED).
 CLOSE SH DRAINS AND VENTS AFTER ACHIEVING DEGREE OF SH 50
°C ( CLOSE IT AFTER CHARGING HP-LP BYPASS).

16. LDO/HFO GUN
Fuel Light Oil
Fuel Pressure 0.8MPa-2.0MPa
Fuel Flow 500kg/h -3000kg/h
Atomizing Air Pressure 0.6MPa-1.2MPa
Atomizing Air Flow 100-600kg/h
Ignition Method HESI (20 joules/spark)
Fuel Heavy Oil
Fuel Pressure 0.8MPa- 2.0MPa
Fuel Flow 1000-4000 kg/h
Atomizing Steam Pressure 0.8MPa-1.2MPa
Atomizing Steam Flow 100-400kg/h
Ignition Method HESI (20 joules/spark)

17. TURBINE LINE UP
 ENSURE:
 LUBE OIL SYSTEM: IN SERVICE (0.8 MPA)
 JACKING OIL SYSTEM:IN SERVICE ( 14 MPA)
 TURBINE BARRING GEAR: 3-4 RPM
 SEAL OIL SYSTEM: AIR & H2 SIDE. CHARGED
 STATOR AND H2 COOLING WATER SYSTEM:CHARGED TEMP CONTROL IN AUTO)
 H2 FILLED IN GENERATOR AND MAINTAIN PR 0.35 MPA.
 EH OIL SYSTEM: IN SERVICE (14 MPA)

18. TURBINE LINE UP
 ENSURE TDBFP IN BARRING.
 GLAND STEAM CHARGING: ENSURE STEAM TEMP. IS 56°C - 111
°C MORE THAN ROTOR TEMP & DEGREE OF SH > 50°C.
 CHARGE THE GLAND SEAL SYSTEM OF TDBFP.
 START THE VACUUM PULLING WITH VACUUM PUMP.
MAINTAIN VACUUM -0.9 KG/CM2.
 CHARGE THE HP-LP BYPASS SYSTEM .MAINTAIN THE MS STEAM
PRESSURE AND FIRING RATE FOR ACHIEVING TURBINE ROLLING
PARAMETERS.

19. COLD START UP CURVE

20. HOT ROLLING
MS TEMP
RH TEMP
SPEED
MS FLOW
LOAD
MS PRESS

21. PRE HEATING OF HP CASING.
 PREHEATING OF HPT REQUIRED WHEN INNER METAL TEMP <150°C.
 CRH PR 0.5-0.7 MPA/220-380°C.
 OPEN PRE HEATING VALVE (REVERSE FLOW VALVE) GRADUALLY.
 OPEN BDV VALVE FULLY.
 OPEN CRH DRAIN BEFORE NRV AND HPT-IPT CASING DRAINS.
 HEATING RATE SHOULD NOT BE MORE THAN 50°C PER HR.
 HP CASING TOP-BOTTOM & INNER-OUTER WALL METAL TEMP DIFFRENCE
SHOULD BE WITHIN 50°C.
 AFTER ATTAINING THE CASING TEMP > 150°C CLOSE THE RFV VALVE AND
OPEN HP CYLINDER VENTILATION VALVE TO CONDENSOR.

22. TURBINE WARM UP OPERATION
TURBINE STARUP PROCEDURE
RFV
CRH NRV
HPT
HPBP
CRH LINE
Ventilator valve
TO CONDENSER
IPT
BDV
TO CONDENSER
MS

23. TURBINE ROLLING
 AS PER REQUIREMENT OF START UP CURVE, FIRING TO BE INCREASED.
 REQUIRED STEAM PARAMETERS BEFORE ROLLING
 MS PR: 8.73 MPA, TEMP: 330-380 °C
 RH PR: 1.1 MPA , TEMP: 330°C
- THE DEGREE OF SUPER HEAT > 56°C.
 AFTER LATCHING THE TURBINE, START IP ROLLING WITH HP VENT TO
CONDENSER IN OPEN CONDITION TO KEEP THE HPT IN VACUUM.
 MSV 1&2 AND RSV 1&2 ARE IN OPEN CONDITION.
 GIVE THE SPEED SET POINT TO 600 RPM
 CHECK THE TURBINE SUPERVISORY INSTRUMENT PARAMETER.
 THE ECCENTRICITY SHOULD BE LESS THAN 0.076 MM.

24. TURBINE ROLLING
 SELECT TARGET SPEED 1500 RPM WITH RAMP RATE OF 100 RPM/MIN.
 ENSURE ALL HP CV’S OPENS TO 12% TO WARM UP THE HP CASING.
 WHEN HP CASING TEMP >320°C.CLOSE THE HP CV’S.
 SOAK THE TURBINE FOR 4 HRS ACCORDING TO THE START UP CURVE.
 CHARGE THE LP HEATER 5 & 6 BEFORE 3000 RPM
 SELECT TARGET SPEED TO 3000 RPM WITH RAMP RATE OF 100
RPM/MIN.SOAK IT FOR 30 MIN AS PER S/U CURVE.
 AS PER PROCEDURE SYNCHRONISE THE UNIT.

25. LOADING
 AFTER SYNCHRONISATION INITIAL LOAD WILL BE 30 MW.HOLD IT FOR 30 MIN AND
CHEK THE VIBRATION, BEARING TEMP, DIFF EXPANSION, CASING EXPANSION.
 CHARGE EXTRACTION STEAM TO DEAERATOR.
 TAKE MORE OIL GUNS IN EF/AB ELEVETION.
 TAKE PA FANS & SEAL AIR FAN.
 AFTER ACHIEVING FURNACE TEMP. MORE THEN 450°C. TAKE COAL MILL-B AT.
STEAM T/PR 380°C/8.7 MPA.
 INCREASE FUEL FLOW MAINTAINING STEAM TEMP.& RAISE LOAD
 AT 70 MW IP TO HP CHANGE OVER. CV’S WILL START OPENING, CLOSE THE BDV
AND VENTILATING VALVE.
 INCREASE THE LOAD AT 3MW/MIN
 CLOSE THE HP-LP BYPASS GRADULLY.

26. 350 400 450 500 550 600 650
MINUTES
LOAD
(MW)
165
330
495
660
33MW
60MW
198MW
330MW
SYNCHRONISE
&CHARGED/A
MILL-BCUTIN
IPTOHPCHANGEOVER(70MW
MILL-CCUTINAT100MW
HPHCHARGED(150MW)
2ND
TDBFPCUTIN(180MW)
WETTODRYCHANGEOVER
MILL-ACUTIN(210MW)
OILGUNCUTOUT(260MW)
MILL-DCITIN(300MW)
MILL-ECUTIN(430MW)
MILL-FCUTIN(540MW)
660 MW

27. CONDENSER
LP HEATER 7A
LP HEATER 8A
CONDENSER
LP HEATER 7B
LP HEATER 8B
LPT A LPT B
HP HEATER 5
HP HEATER 6
LP HEATER 5
LP HEATER 6
2nd 2nd
4th 4th
5th
5th
5th
5th
6th
6th
6th
6th
FROM IPT EXHAUST

28. TDBFP START UP
 TAKE ONE TDBFP IN SERVICE( CHANGE OVER WITH MD BFP) WHILE DRIVING
STEAM IS AVAILABLE. SECOND TD BFP WILL BE TAKEN AT 180 MW.
 WARM UP THE TURBINE.
 SLOWLY OPEN THE AUX STEAM MOV TO TURBINE.
 PARAMETERS FOR ROLLING TDBFP.
STEAM PRESSURE: 0.6 ～ 1.3MPA, STEAM TEMP: 50 DEG C MORE THAN CASING
TEMP.
 ROLL THE TDBFP AS PER PROCEDURE.
 GIVE THE TARGET SPEED 500 RPM AND THAN TO 1000 HOLD FOR 40 MIN.CHECK
THE TSI PARAMETER
 WHEN SPEED REACHES 2840 RPM, GIVE REQUEST COMMAND FROM FW MENU.
THEN SELECT CCS CONTROL IN FROM MEH MENU.

29. IP
TDBFP-A
TDBFP-B
Aux. Steam
Header
To
CRH
HP
From
CRH
M
M M M
Deaerator
Booster
pumps
M M
M
E
E
To
Condenser
Aux. Steam
Header
M
M
M
M M
M M
E
E
Deaerator
1.3 MPa
350 ºC
1.12 Mpa
378 ºC
4 MPa
315.3 ºC
Changeover Valve
TDBFP STEAM SOURCES

30. LOADING
 TAKE THE MILL-C IN SERVICE AT 100 MW. STEAM T/PR:400°C/8.7 MPA.
 GRADUALLY WITH DRAW THE OIL SUPPORT AS PER THE FLAME
CONDITION.
 INCREASE THE LOAD TO 150 MW AND TAKE THE HPH-3, HPH-2 &
HPH-1 IN SERVICE. MS T/PR 410°C/8.7 MPA.
 AT 180 MW TAKE SECOND TDBFP IN SERVICE.

31. HP HEATER 3
DEAERATOR
HP HEATER 2
HP HEATER 1
CRH LINE
TDBFP A TDBFP B
MS LINE
9th
stage
5th stage
HP HEATER 1
HP HEATER 2
HP HEATER 3
HRH LINE
DEAERATOR
IP EXHAUST

32. PHASE CHANGE FROM WET TO DRY MODE
 DURING LOAD RAISING >25% BMCR, THE BCP FLOW AND FEED WATER
FLOW TO BE MONITORED CLOSELY.
 THE BCP FLOW NEED TO BE ADJUSTED W.R.T SEPERATOR TANK LEVEL AND
THE SAME FLOW TO BE ADJUSTED IN FEED WATER FLOW TO MAINTAIN
TOTAL FEED WATER FLOW TO ECONOMISER CONSTANT.
 WHEN BOILER STEAMING RATE RISES TO >30% BMCR, W.R.T FUEL FIRING, THE
SEPERATOR LEVEL REDUCES .
 ONCE THE CONDITION FULFILLS THE BCP STOPS AND FEED FLOW CONTROL
CHANGES OVER FRS.
 AFTER STOPPING BCP IT ACTS AS SUB-CRITICAL ONCE THROUGH“.
 WHEN THE STEAM PR REACHES 22.1 MPA IT IS IN “SUPERCRITICAL ZONE”

33. LOADING
 TAKE MILL-A AT 210 MW.
 CUT THE OIL SUPPORT AT 260 MW AS PER THE FLAME CONDITION.
 TAKE MILL-D AT 300 MW. MS T/PR 475°C/10 MPA.
 TAKE MILL-E AT 430 MW. MS T/PR 566°C/17 MPA.
 TAKE MILL-F AT 540 MW. MS T/PR 566°C/24.1 MPA.
 INCREASE THE LOAD TO “FULL LOAD 660 MW” GRADUALLY.

34. Boiler Design Parameters
NO.NO. ParametersParameters UnitUnit
11
100% BMCR Coal consumption (Design)100% BMCR Coal consumption (Design) 390.37390.37
t/ht/h
22 Design fuelDesign fuel Indian coalIndian coal
33 Superheated steam flowSuperheated steam flow 21112111 t/ht/h
44 Superheater outlet pressureSuperheater outlet pressure 25.425.4 MPaMPa
55 Superheater outlet temperatureSuperheater outlet temperature 569569 ℃℃
66 Reheated steam flowReheated steam flow 1749.11749.1 t/ht/h
77 Reheater inlet pressureReheater inlet pressure 4.734.73 MPaMPa
88 Reheater outlet pressureReheater outlet pressure 4.494.49 MPaMPa
99 Reheater inlet temperatureReheater inlet temperature 324324 ℃℃
1010 Reheater outlet temperatureReheater outlet temperature 569569 ℃℃
Feedwater pressureFeedwater pressure 28.828.8 MPa.gMPa.g
1111 Feedwater temperatureFeedwater temperature 280280 ℃℃
1212 Separator’s steam temperatureSeparator’s steam temperature 421421 ℃℃
1313
Air preheater’s outlet air temperature, uncorrectedAir preheater’s outlet air temperature, uncorrected
After correctingAfter correcting
153.3153.3 ℃℃
147.2147.2 ℃℃
1414 Calculating thermal efficiency of boilerCalculating thermal efficiency of boiler 87.19%87.19% （（ BMCRBMCR ））

35. TURBINE PARAMETERS
HPT IPT LPT
Pressure (MPa) 24.2 3.961 1.12
I/L Temp (Deg C) 566 566 378
O/L Temp(deg C) 315.3 378
Steam Flow (tph) 1959.25 1649
TURBINE HEAT RATE( KCL/KWH) 1885
No of Stop valves 2 2
No of Control valves 4 4
Steam Admission Parameters at Turbine Inlet

36. TURBINEAT FULL LOAD
HPT IPT
RSV
LPT LPT #2 GEN
CRH
CRH
HRH
MS LINE
HRH
MS LINE
3.96MPa / 566°c
24.2MPa/566ºC
TO BLR RH
RCV
MSV
RCVRCV RCVCV CVCV
RSV
CVCV
CVCV
RSV
CVCVMSV
CV CV
LPT LPT #2LPT GEN#2LPTLPT #1
MSV CV CVMSV CVMSV CVMSV CVCVMSV CVMSV CVMSV CV CVMSV
MSV CVMSV CVCVMSV
RSV
CV CV
RSV
CV
RSV
CV
RSV
CVCV
RSV
1.12MPa / 378°c
CONDENSOR A CONDENSOR B

37. SHUT DOWN
 EXCEPT IN AN EMERGENCY, LOAD SHOULD BE REDUCED GRADUALLY.
 CUT THE MILL-F AT 540 MW.
 CUT THE MILL-E AT 470MW.
 CUT THE MILL-D AT 300 MW.
 TAKE OIL SUPPORT FOR FURNACE STABILITY ( AT THE TIME OF 3 MILL
OPERATION).
 CUT THE MILL-A AT 210 MW.
 TAKE THE HPH-1,2,3 OUT OF SERVICE.
 WHEN THE LOAD < 30% BOILER COMES IN WET MODE FROM DRY
MODE. START THE BCP AND MAINTAIN THE SEPEARTOR LEVEL.

38. SHUT DOWN
 WHEN THE LOAD HAS DECREASED TO 20% OF RATED LOAD TRIP THE
TURBINE ON TURBINE PROTECTION. THIS CLOSES THE THROTTLE VALVES,
GOVERNOR VALVES, REHEAT STOP VALVES AND INTERCEPTOR VALVES
 CHECK DRAIN VALVES OPENS IN AUTO.
 HP LP BYPASS VALVE OPENS TO MAINTAIN THE FLOW.
 REDUCE THE BOILER LOAD GRADULLY.
 TRIP THE BOILER.
 THE VACUUM BREAKER VALVES SHOULD NOT BE OPENED UNTIL THE
TURBINE UNIT HAS COASTED DOWN.
 VACUUM SHOULD BE KILLED BEFORE GLAND SEALING STEAM IS SHUT OFF.
 AUX OIL PUMP STARTS IN AUTO AT 2850 RPM.
 JOP START IN AUTO AT 1200 RPM.

39. SHUT DOWN
 WHEN THE VACUUM REACHES ZERO, SHUT OFF THE SEALING STEAM TO THE
GLAND STEAM CONTROL VALVES.
 SHUT DOWN THE GLAND STEAM CONDENSER EXHAUSTER. SHUT DOWN
CONDENSATE PUMP.
 SHUT DOWN THE VACUUM PUMP.
 SHUT OFF THE COOLING WATER SUPPLY TO THE GENERATOR HYDROGEN
COOLERS.
 ENSURE THAT BARRING GEAR HAS CUT IN.

40. SHUT DOWN CURVE

41. COOL DOWN CURVE

42. THANK YOU