DEAERATOR-STAGE-II-TPS-II  ELEVATION OF DEAERATOR FLOOR - 27 METER LEVEL.  THE DEAERATOR IN STAGE-II/TPS-II IS OF COMBINED SPRAY AND TRAY TYPE.IT CONSISTS OF TWO ELEMENTS:  1. A HORIZONTAL FEED WATER STORAGE TANK AT THE BOTTOM SIDE.  2. A HORIZONTAL DEAERATING HEADER LOCATED ON STORAGE TANK, AND CONNECTED AT THE UPPER PART OF THE STORAGE TANK.  OPERATING PRESSURE KSC VARIABLE PRESSURE.  OPERATING TEMPERATURE  C.

 THE CAPACITY OF THE STORAGE TANK IS 130 M3.  DEAERATOR STORAGE TANK IS FABRICATED FROM BOILER QUALITY STEEL PLATES.  IT HAS 3 SUPPORTS IN THE BOTTOM.CENTRAL SUPPORT IS A FIXED ONE AND BOTH END SUPPORTS WITH 2 EXPANSION ROLLERS ARE SLIDING UPTO 8MM TO ACCOMMODATE THE THERMAL EXPANSION.  THE STORAGE TANK IS PROVIDED WITH 2 SAFETY VALVES SET PRESSURE-7KG/CM2.  LIMIT DOWN TO WHICH OXYZEN IS REMOVED CC / LITER.  STORAGE TANK OVERALL DIMENSION IN MM 3500 OD  LENGTH.

 OVERALL DIMENSION IN MM OD  5800 LENGTH.  SPRAY NOZZLE MATERIAL - STAINLESS STEEL.  NUMBER OF SPRAY NOZZLES - 40 NUMBERS.  NUMBER OF VERTICAL STACKS - 2 NUMBERS.  NUMBER OF TRAYS IN EACH STACK - 5 NUMBERS.  MAIN CONDENSATE PIPES CONNECTING HEADER AND STORAGE TANK ARE 2 NUMBERS (LEFT AND RIGHT).  STEAM PIPE CONNECTING HEADER AND STORAGE TANK 1NO - AT THE CENTER.  OVERALL DIMENSION IN MM OD  5800 LENGTH.  SPRAY NOZZLE MATERIAL - STAINLESS STEEL.  NUMBER OF SPRAY NOZZLES - 40 NUMBERS.  NUMBER OF VERTICAL STACKS - 2 NUMBERS.  NUMBER OF TRAYS IN EACH STACK - 5 NUMBERS.  MAIN CONDENSATE PIPES CONNECTING HEADER AND STORAGE TANK ARE 2 NUMBERS (LEFT AND RIGHT).  STEAM PIPE CONNECTING HEADER AND STORAGE TANK 1NO - AT THE CENTER.

SL NOPARAMETER MAIN CONDENSATE AT INLET FEED WATER AT OUTLET 1.ENTHALPHY(KCAL/KG) TEMPERATURE-(  C) PRESSURE8.5 ATA6.5 ATA 4.FLOW530 T/HR660 T/HR

SL NO. CONNECTION FROMCONNECTED TO 1.MAIN CONDENSATE AFTER LP HEATER - 3DEAERATOR HEADER 2.INITIAL FILLING LINE FROM CSTDEAERATOR STORAGE TANK 3.BOILER FEED PUMP RECIRCULATION LINES 3 NO’S:DEAERATOR STORAGE TANK 4.DRAIN CONDENSATE FROM HP HEATERS - 5 & 6DEAERATOR STORAGE TANK WATER OUTLETS TO DEAERATOR SLNO OUTLETCONNECTION FROM 1.FEED WATER SUCTION BUS FOR BOILER FEED PUMP. BOTTOM OF THE DEAERATOR STORAGE TANK.HYDRAZINE HYDRATE DONE AT THE SUCTION BUS OF THE BFP. 2.DEAERATOR OVER FLOW LINEDR-33 OVER FLOW VALVE. 3.DEAERATOR DRIN 2 NUMBERSBOTTOM OF THE DEAERATOR STORAGE TANK

SL NO. CONNECTION FROMCONNECTED TO 1.NORMAL SOURCE OF STEAM FROM 4 TH EXTRACTION FROM IP EXHAUST THROUGH EX-14 VALVE DEAERATOR STORAGE TANK 2.FIRST STANDBY SOURCE OF STEAM CRH STEAM THROUGH EX-001 MOV AND PCV-2. DEAERATOR STORAGE TANK 3.SECOND STANDBY SOURCE OF STEAM PEGGING STEAM THROUGH AUXILIARY STEAM HEADER. DEAERATOR STORAGE TANK 4.PRE-HEATING STEAM THROUGH AUXILIARY STEAM HEADER. DEAERATOR STORAGE TANK 5.CONTINUOUS BLOW DOWN TANK STEAMDEAERATOR STORAGE TANK 6.SHELL VENTS OF HP HEATER 5 & 6 TWO NUMBERS DEAEARATOR HEADER 7.PRE-HEATING STEAM THROUGH AUXILIARY STEAM HEADER. DEAEARATOR HEADER

 DEAERATOR VENTS ARE PROVIDED FOR THE DEAERATING HEADER AS DETAILED BELOW.THEY ARE VENTING THE AIR REMOVED ALONG WITH A PART OF DEAERATING STEAM.  1. ONE VENT WITH PROVISION OF HAND OPERATED ISOLATION VALVE.  2. ONE VENT WITH PROVISION OF MOTOR OPERATED VALVE ‘SM- 20 ’.  TWO NUMBERS OF VENTS PROVIDED WITH AN ORIFICE IN EACH LINE AND WITHOUT ANY VALVE.(UN CONTROLLED VENTS)

SLN O DESCRIPTIONTAG NOSTD BY PIPE LEVEL MM ACTION HI HI WATER LVL SWITCH LS 2020 LS 2021 I2I DEAERATOR LEVEL VERY HIGH ALARM. 2.EX TH EXTRACTION LINE IS CLOSED. 3.EX-108-DRAIN LINE OPENS OVER FLOW VALVE OPEN OVER FLOW VALVE CLOSE LS 2019 LS “DEAERATOR OVER FLOW VALVE DR-33 OPENS” – ALARM. 2.DEAERATOR OVER FLOW VALVE DR-33 OPENS. 1. DEAERATOR OVER FLOW VALVE DR-33 CLOSES. 2. “DEAERATOR OVER FLOW VALVE DR-33 CLOSED” – ALARM RESETS 5.HIGH WATER LEVEL. LS “DEAERATOR LEVEL HIGH” - ALARM. 6.HIGH WATER LEVEL CONTROLLER- TRANSMITTER LT STORAGE TANK 1835SET POINT HIGH LEVEL CONTROLLER. 7.NORMAL WATER LEVEL CONTROLLER- TRANSMITTER LT STORAGE TANK 1585SET POINT NORMAL LEVEL CONTROLLER. 8.LOW WATER LEVEL SWITCH LS “DEAERATOR LEVEL LOW” - ALARM. 2.CD 64 & CD 66 VALVE PROTECTION OPEN. 3.START-UP PERMISSIVE FOR BOILER FEED PUMP. 9.LOW LOW WATER LEVEL LS “DEAERATOR LEVEL VERY LOW” –ALARM. 10.LOW LOW WATER LEVEL LS PROTECTION FOR ALL BOILER FEED PUMP.

 CRH STEAM TO DEAERATOR VALVE EX-001 LOGICS:  1.WHEN THE CRH STEAM PRESSURE > 8 KSC EX-001 AUTO OPEN.  2. WHEN THE CRH STEAM PRESSURE < 8 KSC EX-001 AUTO (PROTECTION) CLOSE.  MANUAL OPENING AND CLOSING PROVISION ALSO POSSIBLE FROM UCD.  4.WHEN CRH STEAM PRESSURE IS LESS THAN 8 KSC, MANUAL OPENING OF EX-001 IS NOT POSSIBLE.  FC NRV IN THE EXTRACTION IV CHECK VALVE A4 LOGIGS:  1.WHEN DIFFERENTIAL PRESSURE ACROSS CHECK VALVE A-4 BECOMES GREATER THEN 0.3 KSC A-4 WILL OPEN AUTO AFTER 2 SECONDS ON ENERGISATION OF SOLENOID OPERATED VALVE - SOV “MAX 57 AA027”.  1. p > 0.3 KSC FC NRV OPEN.  2. p < 0.1 KSC FC NRV PROTECTION CLOSE. SOV DE-ENERGISED.

T.JAGADEESAN DEPUTY CHIEF ENGINEER TURBINE OPERATION THERMAL POWER STATION-II NEYVELI LIGNITE CORPORATION LIMITED