Boiler Start-Up After BTL

Boiler Start-Up After BTL

  • Boiler is out for 1-2 days due to BTL. HP Casing Temp in b/w 300-400 Deg
  • One HFO i/s. HFO charged with >110 Deg upto Boiler Front
  • Start ID and FD fan. Purge Boiler (5 min cycle)
  • Check SH/RH vents Open. APH Soot Blowing lined up.Charge Oil Carry over Probe.
  • Turbine on Barring. Start AB all 4 guns(Atom Steam Pr in b/w 6-7 ksc)
  • Take Another gun CD(all 4). HFO Prssure~8-10 ksc. Drum Metal Temp Rise~2 Deg/min
  • APH Soot Blowing(10-12 ksc Pr) to be done non-stop.
  • Drum  Pr~2 ksc. Close SH/RH Vents. Open HPBP Warm-Up valves. Open BSV bypass valves.
  • Drum Pr~5 ksc. Open BSVs. Open HPBP~10%. Close HPBP Warm up Valves. 
  • Close SH/RH Header drains at ~ 14 ksc(Drum Pr). Put HPBP spray on Auto.
  • FG path of PA fan through. Start one PA Fan and one Seal Air Fan
  • MS Pr~80 ksc & MS Temp~365 Deg. HRH Pr~12 ksc & HRH Temp~325 Deg. Maintain using HPBP and LPBP valves.
  • Float A mill(charge air). Cut in A mill ~ min flow 17 TPH.
  • No SH/RH spray till now. Secondary Air Temp~175 Deg. 1st Mill Before synchronization.
  • Reduce firing accordingly to control Temp Rise
  • Turbine Running ~ 3000 rpm. Synchronise Machine. Take ~50 MW Block Load. 
  • Ensure Closing of HPBP and LPBP valves with spray on Auto. Increase HPBP set point. 
  • Float 2nd Mill(B). Charge all ESP Fields. Increase Mill-A firing.
  • Firing to maintained ~1.5 T/min upto 250 MW to limit any abrupt Temp Rise for that spray is required.
  • Load~60 MW. MS~60 ksc. Load Controller in action. Charge LPH-2 & 3 with Level controller in Auto. 
  • Charge Deaerator Pegging by CRH Ext. Cut in all Auto controllers. Cut in 2nd Mill.
  • Load ~110 MW. MS~80 ksc. Charge PRDS from CRH. Cut HP Heaters and Level controller in auto. Cut in 3rd Mill.
  • Load~150 MW. MS (100 ksc/435 Deg). Start 2nd PA fan(FG & Air Path available)
  • Control MS & RH Temp by spray if Required. Cut in 4th Mill. Check Scanners,'
  • Load~250 MW. MS~125 ksc/450 Deg.  Cut in 5th Mill. Roll 1st TDBFP & Put on Load.
  • Cut-off Oil Support Completely. Cut in 6th Mill if required. 
  • Change MDBFP with TDBFPs. And stop MDBFP.
  • Load~350MW. MS~140ksc/480 Deg. Increase Set point of SH/RH Spray to achieve rated SH and RH Temp
  • Load~500 MW and Scan all Parameters/ Loops/ Controllers.

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