Light-UP Steps

Guidelines & check List for Boiler light-up

CW system: Minimum 3 CW pumps running for stage with CW header Pr ~1.1-1.5 ksc
ACW system:

•  2 pumps in service.
•  Discharge Header Pr 2.3-3.0 ksc

ECW sytem :

•  SG ECW p/p -one pump with Header pr >7.0 ksc 
•  TGECW p/p-Two pump with hdr pr>6 ksc
• ( ECW SG and TG Tank level control on auto)
•  Cooling Water : charge for ID,FD, PA, Mill, APH, 10m & 55m Door cooling etc
•  Lube oil sytem : ID, FD, PA, Mill, APH normal

Scanner fan:

•  START AC scanner fan
•  Discharge Pr>250 mm WC.
•  Take trial of DC scanner fan too

SCAPH:

• PAPH and SAPH SCAPH inlet and outlet damper OPEN with bypass damper CLOSED

PAPHs : Outlet Dampers of Flue Gas CLOSED

ESP pass 

• Normal.
• With Fields Ready to be in charged condition.
• Keep Rapping motor in Auto

Burner Tilt -Horizontal i.e. 50% or at 0 Deg
IAC & PAC: air header pressure >6ksc

Ash Removal:

• Bottom / Fly Ash evacuation Ready.
• Trough seal Charged.
• Ensure Peep hole and manhole Closed.

LDO & HFO:

• pressure in pump house 16 ksc.
• HFO & LDO trip valve CLOSED.
• HFO, LDO, Atomising steam, Atomising air manual isolating valves are OPEN.
• Ensure Short Recirculation valve OPEN.
• All guns AB, CD, EF individual HONV and AS manual valves OPEN.
• Ensure Tracing steam is Charged. Raise HFO temp>120 deg.

Mills: 

• All mills Electrically and Mechanically NORMAL ( MDV and Burner isolating gate OPEN ).
• Ensure BBF-L & BBF-R sprinker NORMAL

RH & SH Header drain :

• OPEN RH & SH drain and Master SH/RH drain .
• SH, RH & Drum VENTS OPEN.
• SH & RH Start-up Vents OPEN
• Boiler SVs CLOSED.

 Low Point Drain: 

• All isoating valves of Low Point drain Station(LPDT) CLOSED

Drum:

• Boiler filled upto NORMAL drum level.
• ECO Recirculation valve OPEN.
• At least one BCW or preferably 2 BCW pump in service.
• MS, CBD, FW sample line NORMAL
• CBD manual at Drum & after CBD station kept OPEN.
• SH, RH spray valve CLOSED.
• HPBP spray: manual valve CLOSED
• ERV: Ensure Opening of motorised isolating valves of ERVS. Keep them in AUTO

APH Soot Blowing:

• lined up from APRDS.
• With Header charged with 30 ksc set point.
• APH oil carryover probe in kept in position.

Drum Filling Procedure:

• RUN MDBFP in Recirculation
• One CEP in Service.
• Ensure pump cavity filled, if not Fill & Purge Cavity of BCW pump. Flush cavity filling line till conductivity < 5 micro mho/cm, PH>6.5 andsolid content<5 ppm. Ensure PH>8 after chemical dosing in FW line . Bring Drum level to NORMAL.
• OPEN Low Load FRS CV( 30% line) isolatig valve and close their Bypass valve.

APH:

• START APHs-Inlet & Oulet of SAPH FG damper OPEN.
• While in PAPH inlet FG damper OPEN and Outlet FG Damper Closed.

Purging & Light-up

• START one set of ID/FD fans. charge SCAPH from steam side.
• START other ID/FD fans.
• charge SCAPH from steam side.
• Air Flow should be maintained around 30-40% of total air flow(>650 TPH and <800 TPH).
• START Boiler PURGING.
• Put SADC in AUTO and maintain WB-Furnace DP around 30-50 mmWC.
• Ensure BSVs(MS-1, MS-2, MS-3, MS-4, Ms-5, MS-6) CLOSED.
• Ensure OPEN drain before Boiler stop valves.
• After completion of scavenging OPEN HORV and then OPEN HOTV.
• Raise Atomising steam temp>200 Deg
• Ensure short Recirculation gets CLOSED in auto after Opening of HOTV
• Light up the Boiler. Check for any Oil leakage.

Boiler Lighted Up & HP/LP Bypass charged:

• START APH soot blowing.
• SCAPH in service.
• Drum Metal Temperature DT monitor.
• Seal Steam Pressure controller in Auto and suplly Temperature> 250 deg.
• No change in Turbine speed after charging of HP/LP bypass.
• Check Load Reference to be 50 MW as per logic in auto Rolling through ATRS.Pr Max Load Limter at 60 MW.
• CBD kept OPEN.
• Check Hotwell, Deaerator, Drum Levels, HFO and LDO pressures.
• HP & LP dosing pump as per Chemist advice.
• Both vacuum pumps in service. Open HPBP spray manual valve when Downstream temperature crossing 300 deg and SH/ RH spray after UNIT synchronisation.
• Check Seal air Fan STARTS on Auto alongwith PA fan and DP>500 mm WC.
• ESP fields put in service after 1st Mill taken in service.
• GRP relay RESET. Written clerance from Chemist for Turbine Rolling.

Turbine Rolled upto 3000 rpm:

• Barring gear CLOSED at speed > 240 rpm.
• JOP stops at speed >540rpm.
• AOP stops at speed >2850 rpm.
• One TDBFP rolled and in Recirculation.
• Excitation in Auto. Tracking Device ON and tracking EHC.
• Load controller active, Raise set point if required. Ensure speed set point is tracking actual speed by 15 rpm after load controller takes over.
• SLC drain in Auto. HP/LP bpass closed.
• All the Heaters LPH-2.3, D/A and Extraction valves to TDBFPs are charged. LPH-2 & 3 level control on Auto.
• Keep CRH drain open for some time. All Turbine side drain vales CLOSED(except Extraction 5 & 6).
• HP Turbine Top/Bottom DT & IP Turbine Front/Rear top/ Bottom DT< Trip value.
• Gland seal Pressure Controller on Auto.
• Check TSE margin> 10K. Check HP Exhaust Temperature.
• Check HRH Pr. Furnace Pressure controller and PA Pressure controller

After Crossing 60% Load:

• HP Heaters are CHARGED.
• Level Controllers on AUTO.
• EXT 5&6 drains CLOSED.
• Check Scanners for healthy fireBall flam before withdrawing Oil Support.
• ESP fiels are charged.
• APH soot blowing STOP.
• SCAPH isolated.
• Mill Rejects cleaning cleaning in progress.
• CBD silica/ Drum Pressure Restrictions are monitored.
• Check all level controllers in AUTO like Drum, Hotwell, Deaerator, PW, Lube oil, HPCF, Gas Temp.
• Both TDBFPs in service and on AUTO.
• All FCNRVs in extraction lines OPEN.

Guidelines for Unit Shutdown

Boiler Side:

• Both PA fans tripped.
• All Mills Tripped. All Feeders tripped.
• HOTV closed. LOTV closed. All Scanners NO Flame. HFO & LDO Nozzle valve closed.
• All HAG closed.
• SH/ RH spray valves Closed.
• Burner Tilt Horizontal.
• Drum Level Normal.
• PAPHs outlet FG Damper Closed.
• Close BSV if Boiler is not going to be Lighted up immediately.
• If boiler trips due to either ID or FD fans trips, as soon as Fans are Ready,START one set of ID/ FD fans and PURGE the boiler. If Boiler Force cooling is required for any repair work in Pressure Parts, Continue Running of ID/FD fans with around 1000 TPH air flow alongwith at leastone BCW Pumps in Service. Otherwise ID/FD fans can be stopped after PURGING the boiler.

Turbine/ Generator Side:

• All Turbine SV and CV Closed.
• GCB/ Field Breaker OPEN.
• Turbine speed Coasting Down.
• CRH NRV and FCNRVs Closed.
• AOP come in Auto <2850 rpm.
• HP evacuation valve OPEN & Close as per logic.
• Condenser Vacuum Normal.
• All Extraction valves LPH-2,3, HPH-5A, 6A, 5B, 6B Closed.
• MDBFP running in recirculation to maintain Drum Level.
• TDBFPs on Barring gear.
• HPBP in Closed condition.
• HPBP spray line manual valve closed.
• HRH Pr should be <12 ksc.
• Check all MAL drains Open.
• Check motorised drain in CRH line in Open condition.
• JOP starts at 510 rpm.
• Barring gear OPEN at 210 rpm.
• Note Time taken from 3000 rpm to 510 rpm(JOP cut in), 210 rpm(barring gear Open), 120 rpm(barring with vacuum), 85 rpm(vacuum killed )

Activities After Turbine on Barring:

• Check Hotwell, Deaerator Level.
• One CW pump Stop. Switch off all ESP field after Boiler Trip.
• Before killing vacuum Ensure
• BSV closed
• MS, CRH, HRH pressures 0 ksc else use HP/LP bypass to Depressurise.
• Close seal steam warm-up drain valve.
• Manual isolation valves at Oil elevations Closed.
• Open GCB isolator if the unit will shutdown for >2 hours.